143 results on '"cover change"'
Search Results
2. 基于多源遥感的淮南矿区土地利用 / 覆盖变化分析.
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李兵, 胡林, 陈晨, 李浩, and 詹绍奇
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Comprehensive use of multi-source remote sensing data, the method of combining object-oriented image analysis and visual interpretation was used to interpret the land use or cover of Huainan mining area in 2007, 2010, 2013, 2016 and 2019. Through the calculation of statistics, dynamic degree, diversity index, utilization degree index and transfer matrix for each land use or cover type area and its proportion, the spatial and temporal change characteristics of land use or cover in Huainan mining area between 2007 and 2019 were analyzed. The results show as follows. The area and proportion of cultivated land in Huainan mining area has been declining continuously, a large number of cultivated land were destroyed, resulting in soil erosion, followed by urban and industrial land, and occupied by solid waste. The order of dynamic degree of all land use or cover types was waterlogging subsidence area > lake reservoir > solid waste > industrial and mining land > forest land > bare land > urban land > road > cultivated land > rural residential land, indicating that coal mining activities have a great impact on land use in mining areas. All mine land use or cover types were disturbed by human activities, and the land use diversity index and land use degree index increased. [ABSTRACT FROM AUTHOR]
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- 2023
3. Analizando trayectorias de uso del suelo. Una propuesta de clusterización.
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Rosati, Germán
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SEQUENCE analysis , *URBAN growth , *LAND use , *CLIMATE change , *PROTOTYPES - Abstract
This paper presents a methodological alternative to analyze land use trajectories. It takes as a case study and prototype an analysis of changes in land use at a general level in Argentina (the Pampas region, the Northwest, the Northeast, and Cuyo, excluding the Patagonia). The objective is to obtain a map with the highest possible resolution that allows to detect the following situations: 1) areas of recent agrarian frontier expansion; 2) areas of “consolidated” agriculture, and 3) areas of recent urban expansion. This paper focuses especially on the development of the applied methodology and a first attempt to validate it. Based on data from the European Space Agency (ESA) linked to the "Climate Change Initiative-Land" (ESA-CCI-LC) for the 1992-2020 period, a clustering of land use trajectories from distances is generated by means of editing distances (used for sequence analysis). There were 29 types of pixel-level trajectories obtained, validated by visual analysis, with an acceptable performance for detection of different trajectories. [ABSTRACT FROM AUTHOR]
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- 2023
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4. A new model to analyze urban flood risk. Case study: Veracruz, Mexico.
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Zúñiga, Emmanuel, Novelo Casanova, David A., Domínguez, Christian, García Benítez, Marcelino, and Piña, Violeta
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URBAN land use , *CLIMATE change models , *FLOOD risk , *FLOOD warning systems , *AUTOREGRESSIVE models , *BODIES of water , *PEARSON correlation (Statistics) - Abstract
Due to their frequency and magnitude, urban floods affect different regions of the world. For this reason, several methodologies integrate information on hazard (H) and vulnerability (V) using a «Classic» Risk (R) model for risk analysis. However, this combination of variables generally overestimates the risk in places where the frequency of flooding is low. In this work we propose a model that we call «Adjusted Risk» (AR) that integrates values of urban proximity (p) to bodies of water, as a tool to assess the risk of floods. The comparison between the R and AR models showed a higher efficiency of AR to reproduce the frequency of floods for 210 cities in Veracruz, while R overestimated the level of risk in cities with low frequency of floods. The correlation values associated with the frequency of flood events for a period of 45 years (1970-2015), allow to establish the utility of the AR model to evaluate the risk of urban floods when using different scales of analysis. [ABSTRACT FROM AUTHOR]
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- 2022
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5. Monitoring spatiotemporal variation of groundwater level and salinity under land use change using integrated field measurements, GIS, geostatistical, and remote-sensing approach: case study of the Feija aquifer, Middle Draa watershed, Moroccan Sahara.
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Moumane, Adil, El Ghazali, Fatima Ezzahra, Al Karkouri, Jamal, Delorme, Jonathan, Batchi, Mouhcine, Chafiki, Driss, and Karmaoui, Ahmed
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WATER table ,LAND use ,WATERMELONS ,SALINITY ,DESERTS ,WATER shortages ,AQUIFERS ,SOIL salinity - Abstract
The cultivation of watermelons has been a fast growing agriculture industry in the arid, desert regions of Morocco, relying on groundwater pumping and transformation of rangelands to farms due to growing demand for the fruit in national and international markets. This study aims to measure the impact of watermelon expansion on groundwater resources in the Feija Basin, which is one of the largest watermelon cultivation areas in Southern Morocco. Field measurements, statistics, Kriging interpolation, and regression methods were used to measure the temporal variations in the groundwater level (GL) and salinity between 2013 and 2018 to determine the correlation between different parameters. Remote sensing data was also used to monitor the watermelon cultivation expansion. Results show a rapid expansion of agricultural areas from just 185.11 ha in 2007 to 2560.1 ha in 2018. The groundwater level declined rapidly by about 10 m below ground level during the 5 years of the study period. Additionally, the decline was accompanied by a significant increase in electrical conductivity (salinity) values over the same time interval from 1077.55 to 1211.9 µS/cm. As a consequence of the continuous overexploitation and unsustainable management, a lot of wells have run dry and there have been drinking water shortages in the city of Zagora, the closest city nearby. Results can help target efforts to improve the implementation of conservation strategies to ensure the sustainability of water use and food production in this region of Morocco. [ABSTRACT FROM AUTHOR]
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- 2021
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6. Forest cover change analysis based on temporal gradients of the vertical structure and density
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Adilson Berveglieri, Nilton N. Imai, Antonio M.G. Tommaselli, Rorai P. Martins-Neto, Gabriela Takahashi Miyoshi, and Eija Honkavaara
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Cover change ,Historical image ,Photogrammetry ,Temporal gradient ,Tropical forest ,Ecology ,QH540-549.5 - Abstract
Canopy height is an important attribute that allows characterizing the forest vertical structure and analyze changes in vegetation cover over time. The objective of this study is to develop an approach for a spatio-temporal analysis of the tropical forest canopy using multi-temporal photogrammetric images. The datasets based on film and digital cameras are used to generate canopy height models and extract structural variables (tree height, relative variance between tree heights, and density of higher trees in the upper canopy). The combination of these variables is used in the analysis. Each variable is segmented into ordinal categorical classes in its respective dataset with temporal class gradients being obtained between the periods of the multi-temporal datasets. Experiments were conducted in a tropical forest under regeneration and with diversity of tree species in different successional stages. Three sets of images (years 1978, 2010, and 2017) were used for analyzing canopy cover changes. A classification based on histograms of gradient classes indicated and quantified the most frequent behavior of the canopy over time. The results showed that the most significant variations in cover changes could be explained by 13 classes of temporal gradients, which described 88% of the canopy. This classification was validated with field data collected in sample plots. From the results, it can be concluded that the proposed approach provides accurate assessments of the spatio-temporal canopy cover changes for forest management.
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- 2021
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7. Global shocks, cascading disruptions, and (re-)connections:viewing the COVID-19 pandemic as concurrent natural experiments to understand land system dynamics
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Piquer-Rodríguez, María, Friis, Cecilie, Andriatsitohaina, R. Ntsiva N., Boillat, Sébastien, Roig-Boixeda, Paula, Cortinovis, Chiara, Geneletti, Davide, Ibarrola-Rivas, Maria-Jose, Kelley, Lisa C., Llopis, Jorge C., Mack, Elizabeth A., Nanni, Ana Sofía, Zaehringer, Julie G., Henebry, Geoffrey M., Piquer-Rodríguez, María, Friis, Cecilie, Andriatsitohaina, R. Ntsiva N., Boillat, Sébastien, Roig-Boixeda, Paula, Cortinovis, Chiara, Geneletti, Davide, Ibarrola-Rivas, Maria-Jose, Kelley, Lisa C., Llopis, Jorge C., Mack, Elizabeth A., Nanni, Ana Sofía, Zaehringer, Julie G., and Henebry, Geoffrey M.
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ContextFor nearly three years, the COVID-19 pandemic has disrupted human well-being and livelihoods, communities, and economies in myriad ways with consequences for social-ecological systems across the planet. The pandemic represents a global shock in multiple dimensions that has already, and is likely to continue to have, far-reaching effects on land systems and on those depending on them for their livelihoods.ObjectivesWe focus on the observed effects of the pandemic on landscapes and people composing diverse land systems across the globe.MethodsWe highlight the interrelated impacts of the pandemic shock on the economic, health, and mobility dimensions of land systems using six vignettes from different land systems on four continents, analyzed through the lens of socio-ecological resilience and the telecoupling framework. We present preliminary comparative insights gathered through interviews, surveys, key informants, and authors' observations and propose new research avenues for land system scientists.ResultsThe pandemic's effects have been unevenly distributed, context-specific, and dependent on the multiple connections that link land systems across the globe.ConclusionsWe argue that the pandemic presents concurrent "natural experiments" that can advance our understanding of the intricate ways in which global shocks produce direct, indirect, and spillover effects on local and regional landscapes and land systems. These propagating shock effects disrupt existing connections, forge new connections, and re-establish former connections between peoples, landscapes, and land systems.
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- 2023
8. Global shocks, cascading disruptions, and (re-)connections: viewing the COVID-19 pandemic as concurrent natural experiments to understand land system dynamics
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Piquer-Rodríguez, María, Friis, Cecilie, Andriatsitohaina, R. Ntsiva N., Boillat, Sébastien, Roig-Boixeda, Paula, Cortinovis, Chiara, Geneletti, Davide, Ibarrola-Rivas, Maria-Jose, Kelley, Lisa C., Llopis, Jorge C., Mack, Elizabeth A., Nanni, Ana Sofía, Zähringer, Julie G., and Henebry, Geoffrey M.
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Mobility ,Governance ,Ecology ,Resilience ,MIGRATION ,Geography, Planning and Development ,SURFACE PHENOLOGY ,Conservation ,Telecoupling ,COVER CHANGE ,ABANDONMENT ,Socio-ecological land systems ,500 Naturwissenschaften und Mathematik::550 Geowissenschaften, Geologie::550 Geowissenschaften ,570 Life sciences ,biology ,DEFORESTATION ,COMMON AGRICULTURAL POLICY ,RUSSIA ,Nature and Landscape Conservation - Abstract
Context For nearly three years, the COVID-19 pandemic has disrupted human well-being and livelihoods, communities, and economies in myriad ways with consequences for social-ecological systems across the planet. The pandemic represents a global shock in multiple dimensions that has already, and is likely to continue to have, far-reaching effects on land systems and on those depending on them for their livelihoods. Objectives We focus on the observed effects of the pandemic on landscapes and people composing diverse land systems across the globe. Methods We highlight the interrelated impacts of the pandemic shock on the economic, health, and mobility dimensions of land systems using six vignettes from different land systems on four continents, analyzed through the lens of socio-ecological resilience and the telecoupling framework. We present preliminary comparative insights gathered through interviews, surveys, key informants, and authors’ observations and propose new research avenues for land system scientists. Results The pandemic’s effects have been unevenly distributed, context-specific, and dependent on the multiple connections that link land systems across the globe. Conclusions We argue that the pandemic presents concurrent “natural experiments” that can advance our understanding of the intricate ways in which global shocks produce direct, indirect, and spillover effects on local and regional landscapes and land systems. These propagating shock effects disrupt existing connections, forge new connections, and re-establish former connections between peoples, landscapes, and land systems.
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- 2023
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9. A new model to analyze urban flood risk. Case study: Veracruz, Mexico
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Zúñiga Tovar, Ángel Emmanuel, Novelo Casanova, David A., Domínguez Sarmiento, Christian, García Benítez, Marcelino, Piña, Violeta, Zúñiga Tovar, Ángel Emmanuel, Novelo Casanova, David A., Domínguez Sarmiento, Christian, García Benítez, Marcelino, and Piña, Violeta
- Abstract
Due to their frequency and magnitude, urban floods affect different regions of the world. For this reason, several methodologies integrate information on hazard (H) and vulnerability (V) using a «Classic» Risk (R) model for risk analysis. However, this combination of variables generally overestimates the risk in places where the frequency of flooding is low. In this work we propose a model that we call «Adjusted Risk» (AR) that integrates values of urban proximity (p) to bodies of water, as a tool to assess the risk of floods. The comparison between the R and AR models showed a higher efficiency of AR to reproduce the frequency of floods for 210 cities in Veracruz, while R overestimated the level of risk in cities with low frequency of floods. The correlation values associated with the frequency of flood events for a period of 45 years (1970-2015), allow to establish the utility of the AR model to evaluate the risk of urban floods when using different scales of analysis., Debido a su frecuencia y magnitud, las inundaciones urbanas afectan a diferentes regiones del mundo. Por esta razón, varias metodologías integran información sobre peligro (P) y vulnerabilidad (V) utilizando un modelo de Riesgo «Clásico» (R) para el análisis de riesgos. Sin embargo, esta combinación de variables generalmente sobreestima el riesgo en lugares donde la frecuencia de inundaciones es baja. En este trabajo proponemos un modelo al que llamamos «Riesgo Ajustado» (RA) que integra valores de proximidad urbana (p) a cuerpos de agua, como herramienta para evaluar el riesgo de inundaciones. La comparación entre los modelos R y RA mostró una mayor eficiencia de RA para reproducir la frecuencia de inundaciones para 210 ciudades de Veracruz; mientras que R sobreestimó el nivel de riesgo en ciudades con baja frecuencia de inundaciones. Los valores de correlación asociados con la frecuencia de eventos de inundación para un período de 45 años (1970-2015), permiten establecer la utilidad del modelo RA para evaluar el riesgo de inundaciones urbanas cuando se utilizan diferentes escalas de análisis.
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- 2022
10. Distinction of driver contributions to wetland decline and their associated basin hydrology around Iran
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Panahi, Davood Moshir, Destouni, Georgia, Kalantari, Zahra, Zahabiyoun, Bagher, Panahi, Davood Moshir, Destouni, Georgia, Kalantari, Zahra, and Zahabiyoun, Bagher
- Abstract
Study region: Six wetland sites around Iran (Gavkhoni and Hur al-Azim wetlands, Gorgan Bay, and Namak, Urmia, and Maharloo & Bakhtegan lakes) and their associated hydrological basins. Study focus: The aim was to distinguish the contributions of climatic and non-climatic changes (including land-use/land-cover, LULC) to areal decline in six Iranian wetlands. This was done using data-driven quantification methodology that combined comparative change correlation and Budyko-based analyses of evapotranspiration (ETb), and runoff (Rb) changes in the hydrological basin of each wetland, extended to consider explicitly climate-driven change in evaporation rate (Ew) from the wetland area and the shift from previous Ew to ETb caused by the wetland decline itself. New hydrological insights for the region: Comparative correlation analysis revealed an overall stronger correlation of wetland decline with LULC changes (mainly cropland, urban land) than with changes in temperature (T) or precipitation (P) across all wetland sites. The extended Budyko-based analysis revealed that the predominant cause of wetland decline across all sites was increased ETb, with related decrease in Rb from basin to wetland, whereas changes in Ew and in wetland decline shifting Ew to ETb had only a weak influence. In line with the correlation analysis results, non-climatic drivers were revealed as causing ETb increases and Rb decreases, leading to wetland decline to a greater degree than climate change (T, P).
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- 2022
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11. Detection and characterization of coastal tidal wetland change in the northeastern US using Landsat time series
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Yang, Xiucheng, Zhu, Zhe, Qiu, Shi, Kroeger, Kevin D., Zhu, Zhiliang, Covington, Scott, Yang, Xiucheng, Zhu, Zhe, Qiu, Shi, Kroeger, Kevin D., Zhu, Zhiliang, and Covington, Scott
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© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Yang, X., Zhu, Z., Qiu, S., Kroeger, K. D., Zhu, Z., & Covington, S. Detection and characterization of coastal tidal wetland change in the northeastern US using Landsat time series. Remote Sensing of Environment, 276, (2022): 113047, https://doi.org/10.1016/j.rse.2022.113047., Coastal tidal wetlands are highly altered ecosystems exposed to substantial risk due to widespread and frequent land-use change coupled with sea-level rise, leading to disrupted hydrologic and ecologic functions and ultimately, significant reduction in climate resiliency. Knowing where and when the changes have occurred, and the nature of those changes, is important for coastal communities and natural resource management. Large-scale mapping of coastal tidal wetland changes is extremely difficult due to their inherent dynamic nature. To bridge this gap, we developed an automated algorithm for DEtection and Characterization of cOastal tiDal wEtlands change (DECODE) using dense Landsat time series. DECODE consists of three elements, including spectral break detection, land cover classification and change characterization. DECODE assembles all available Landsat observations and introduces a water level regressor for each pixel to flag the spectral breaks and estimate harmonic time-series models for the divided temporal segments. Each temporal segment is classified (e.g., vegetated wetlands, open water, and others – including unvegetated areas and uplands) based on the phenological characteristics and the synthetic surface reflectance values calculated from the harmonic model coefficients, as well as a generic rule-based classification system. This harmonic model-based approach has the advantage of not needing the acquisition of satellite images at optimal conditions (i.e., low tide status) to avoid underestimating coastal vegetation caused by the tidal fluctuation. At the same time, DECODE can also characterize different kinds of changes including land cover change and condition change (i.e., land cover modification without conversion). We used DECODE to track status of coastal tidal wetlands in the northeastern United States from 1986 to 2020. The overall accuracy of land cover classification and change detection is approximately 95.8% and 99.8%, respectively. The veg, This study was supported by USGS North Atlantic Coast Cooperative Ecosystem Studies Unit (CESU) Program for Detection and Characterization of Coastal Tidal Wetland Change (G19AC00354).
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- 2022
12. Hybridization may aid evolutionary rescue of an endangered East African passerine
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Daniel Vedder, Luc Lens, Claudia A. Martin, Petri Pellikka, Hari Adhikari, Janne Heiskanen, Jan O. Engler, Juliano Sarmento Cabral, and Department of Geosciences and Geography
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Zosterops silvanus ,1171 Geosciences ,5203 Global Development Studies ,LANDSCAPE ,TAITA HILLS ,CONSERVATION ,MODELS ,Biology and Life Sciences ,habitat change ,introgressive hybridization ,COVER CHANGE ,ddc:570 ,evolutionary rescue ,Genetics ,ADAPTIVE INTROGRESSION ,General Agricultural and Biological Sciences ,Taita Hills ,ADAPTATION ,individual-based model ,Ecology, Evolution, Behavior and Systematics ,1172 Environmental sciences - Abstract
Introgressive hybridization is a process that enables gene flow across species barriers through the backcrossing of hybrids into a parent population. This may make genetic material, potentially including relevant environmental adaptations, rapidly available in a gene pool. Consequently, it has been postulated to be an important mechanism for enabling evolutionary rescue, that is the recovery of threatened populations through rapid evolutionary adaptation to novel environments. However, predicting the likelihood of such evolutionary rescue for individual species remains challenging. Here, we use the example of Zosterops silvanus, an endangered East African highland bird species suffering from severe habitat loss and fragmentation, to investigate whether hybridization with its congener Zosterops flavilateralis might enable evolutionary rescue of its Taita Hills population. To do so, we employ an empirically parameterized individual-based model to simulate the species' behaviour, physiology and genetics. We test the population's response to different assumptions of mating behaviour and multiple scenarios of habitat change. We show that as long as hybridization does take place, evolutionary rescue of Z. silvanus is likely. Intermediate hybridization rates enable the greatest long-term population growth, due to trade-offs between adaptive and maladaptive introgressed alleles. Habitat change did not have a strong effect on population growth rates, as Z. silvanus is a strong disperser and landscape configuration is therefore not the limiting factor for hybridization. Our results show that targeted gene flow may be a promising avenue to help accelerate the adaptation of endangered species to novel environments, and demonstrate how to combine empirical research and mechanistic modelling to deliver species-specific predictions for conservation planning.
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- 2022
13. From statistics to grids: A two-level model to simulate crop pattern dynamics
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XIA Tian, WU Wen-bin, ZHOU Qing-bo, Peter H. VERBURG, YANG Peng, HU Qiong, YE Li-ming, ZHU Xiao-juan, and Environmental Geography
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CLIMATE-CHANGE ,Ecology ,NORTHEAST CHINA ,AREA ,spatialization ,crop planting pattern ,Plant Science ,LAND-USE CHANGE ,simulation ,Biochemistry ,SOIL ,COVER CHANGE ,remote sensing ,Food Animals ,Earth and Environmental Sciences ,SPATIOTEMPORAL CHANGES ,ADAPTATIONS ,Animal Science and Zoology ,spatiotemporal change ,Agronomy and Crop Science ,SYSTEM ,Food Science - Abstract
Crop planting patterns are an important component of agricultural land systems. These patterns have been significantly changed due to the combined impacts of climatic changes and socioeconomic developments. However, the extent of these changes and their possible impacts on the environment, terrestrial landscapes and rural livelihoods are largely unknown due to the lack of spatially explicit datasets including crop planting patterns. To fill this gap, this study proposes a new method for spatializing statistical data to generate multitemporal crop planting pattern datasets. This method features a two-level model that combines a land-use simulation and a crop pattern simulation. The output of the first level is the spatial distribution of the cropland, which is then used as the input for the second level, which allocates crop censuses to individual gridded cells according to certain rules. The method was tested using data from 2000 to 2019 from Heilongjiang Province, China, and was validated using remote sensing images. The results show that this method has high accuracy for crop area spatialization. Spatial crop pattern datasets over a given time period can be important supplementary information for remote sensing and thus support a wide range of application in agricultural land systems.
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- 2022
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14. Land degradation along a climatic gradient in Mali: Farmers' perceptions of causes and impacts
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Patrice Savadogo, Markku Larjavaara, Adama Diakité, Jules Bayala, Eshetu Yirdaw, Ibrahim Toure, Department of Forest Sciences, Viikki Tropical Resources Institute (VITRI), Eshetu Yirdaw Eshetu / Principal Investigator, and Forest Ecology and Management
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restoration ,010504 meteorology & atmospheric sciences ,Environmental change ,dryland ,Soil Science ,DETERMINANTS ,environmental-change ,Development ,01 natural sciences ,West africa ,HIGHLANDS ,Climatic gradient ,MANAGEMENT ,SOIL FERTILITY ,Environmental Chemistry ,KNOWLEDGE ,WestAfrica ,Natural resource management ,BURKINA-FASO ,WEST-AFRICA ,1172 Environmental sciences ,0105 earth and related environmental sciences ,General Environmental Science ,2. Zero hunger ,4112 Forestry ,Agroforestry ,agro-ecological zone ,CONSTRAINTS ,04 agricultural and veterinary sciences ,15. Life on land ,COVER CHANGE ,Geography ,natural resource management ,13. Climate action ,040103 agronomy & agriculture ,Land degradation ,0401 agriculture, forestry, and fisheries ,Soil fertility ,RESPONSES - Abstract
Land degradation (LD) in Mali is prevalent and leads to an enduring environmental and humanitarian crisis. Farmers' ecological knowledge has proven to be a valuable tool in addressing its challenges. How farmers perceive LD affects how they deal with induced risks, and their responses to these perceptions will shape restoration options and outcomes. Therefore, this study assessed farmers' perceptions of LD along a climatic gradient in three regions of Mali. We interviewed 270 farmers, and we analyzed their responses using descriptive statistics and Spearman rank‐order correlation. We found that the respondents were aware of LD and have identified its key indicators and its impacts on their livelihoods. Moreover, we found that farmers' perceptions are not influenced by gender, age, or education level, but rather by agricultural training, participation in agricultural labor, the practice of fallowing, shortage of firewood, livestock, household size, appearance of some plant species and famine. Additionally, farmers' perceptions of LD vary along the climatic gradient as they correlate to different variables in each agro‐ecological zone. LD's impacts, however, decrease in severity along the north–south gradient, although they are linked to the same variables. As LD is seen through a reduction of ecosystem services provisioning capacity because of the local communities' heavy dependence on natural resources, actions should be geared towards agronomic and vegetative land management options. Such actions should prioritize context‐specific soil and water conservation techniques and proven indigenous practices.
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- 2020
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15. Attribution of changes in the water balance of a basin to land-use changes through combined modelling of basin hydrology and land-use dynamics
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Mert Can Gunacti, Fulya Aydin Kandemir, Mohamed Najar, Aysegul Kuzucu, Meltem Uyar, Filiz Barbaros, Hulya Boyacioglu, Gulay Onusluel Gul, and Ali Gul
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Atmospheric Science ,Global and Planetary Change ,water resources management ,Climate ,cover flow ,Management, Monitoring, Policy and Law ,Menderes River-Basin ,Gis ,hydrology simulation ,Recharge ,statistical analysis ,SWAT model ,Mediterranean region ,Prediction ,Water Science and Technology ,Cover Change - Abstract
Land use and land cover change (LULCC) is considered one of the major drivers of climate change, although climate change can also foster direct or indirect influences leading to LULCC. The objective of the presented study is to offer a strategic observation frame as the land use and land cover (LULC) transitions are grouped to define the cover flows (CFs). The Küçük Menderes River Basin (KMRB), which is located in the west of Turkey was examined as the case study. Through LULCC modelling via the employment of multi-layer perceptron (MLP), cellular automata (CA), and Markov Chain methods, future LULC maps were projected up to the horizon of 2050. Hydrologic responses of the basin to LULCC were determined by the developed hydrologic model, which is generated by the Soil and Water Assessment Tool (SWAT). The superimposed impacts of the examined effects of LULCC have been investigated by the CF types. This way, the individual impacts of the CFs have been assessed. In the case of the KMRB, projected annual runoffs for the year 2050 cover map represent a 9.06% reduction and the major responsible CF type for this reduction is the conversion from forest to non-irrigated agricultural land cover by 22.90%.
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- 2022
16. Cambios en la cobertura de manglares en Bahía Culebra, Pacífico Norte de Costa Rica (1945-2010).
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Benavides-Varela, Catalina, Samper-Villarreal, Jimena, and Cortés, Jorge
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Changes in mangrove coverage in Culebra Bay, North Pacific of Costa Rica (1945-2010). Despite the economic and environmental services that mangroves provide, they continue to be threatened by overexploitation, pollution, and land use change. Costa Rica has mangrove areas on the Pacific and Caribbean coasts, and cover has been declining since the 1980s. However, data on mangrove coverage are not continually updated and are often based on inaccurate estimates. It is therefore necessary to assess the current extension and variation of the mangrove cover in recent years, to determine changes. The mangrove cover was analyzed in two mangrove forests located in Bahía Culebra, North Pacific: Iguanita and Playa Panamá. For this, aerial photographs and satellite imagery were used to study changes for a 65 year period (1945-2010). Spatio-temporal changes were found in mangrove coverage, adjacent forests and areas without vegetation. Lower mangrove cover occurred during the 1970s (28.4 ha in Iguanita and 4.8 ha in Playa Panamá); but increased in recent years (38.9 ha in Iguanita and 12.0 ha in Panamá). Changes in forest cover by the Iguanita and Playa Panama mangroves were related to the history of land use around Bahía Culebra. Before 1980, there was extensive and intensive cattle ranching, increasing the deforestation rate; after that year, these practices were abandoned and secondary forest coverage increased until 2000. To ensure the adequate protection of mangroves, it is not only important to protect mangrove forests, but it is also necessary to establish buffer zones on their surroundings, to mitigate and/or reduce possible impacts. Rev. Biol. Trop. 64 (3): 955-964. Epub 2016 September 01. [ABSTRACT FROM AUTHOR]
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- 2016
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17. Increasing the Depth of a Land Surface Model. Part I: Impacts on the Subsurface Thermal Regime and Energy Storage
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González Rouco, Jesús Fidel, Steinert, N. J., García Bustamante, Elena, Hagemann, S., De Vrese, P., Jungclaus, J. H., Lorenz, S. J., Melo Aguilar, C., García Pereira, F., Navarro, J., González Rouco, Jesús Fidel, Steinert, N. J., García Bustamante, Elena, Hagemann, S., De Vrese, P., Jungclaus, J. H., Lorenz, S. J., Melo Aguilar, C., García Pereira, F., and Navarro, J.
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© 2021 American Meteorological Society. L Thanks to R. Schnur and V. Gayler from MPI Hamburg. We gratefully acknowledge the IlModels (CGL2014-59644-R) and GreatModelS (RTI2018102305-B-C21 and RTI2018-102305-A-C22) projects funded by the Spanish MINECO. SH contributed in the frame of the ERANET-plus-Russia project SODEEP (Study Of the Development of Extreme Events over Permafrost areas) supported by BMBF (Grant 01DJ18016A). This work used resources of the Deutsches Klimarechenzentrum (DKRZ) granted by its Scientific Steering Committee (WLA) under project ID bm1026., The representation of the thermal and hydrological states in land surface models is important for a realistic simulation of land-atmosphere coupling processes. The available evidence indicates that the simulation of subsurface thermodynamics in Earth system models is inaccurate due to a zero-heat-flux bottom boundary condition being imposed too close to the surface. To assess the influence of soil model depth on the simulated terrestrial energy and subsurface thermal state, sensitivity experiments have been carried out in piControl, historical, and RCP scenarios. A deeper bottom boundary condition placement has been introduced into the JSBACH land surface model by enlarging the vertical stratification from 5 to 12 layers, thereby expanding its depth from 9.83 to 1416.84 m. The model takes several hundred years to reach an equilibrium state in stand-alone piControl simulations. A depth of 100 m is necessary, and 300 m recommendable, to handle the warming trends in historical and scenario simulations. Using a deep bottom boundary, warming of the soil column is reduced by 0.5 to 1.5 K in scenario simulations over most land areas, with the largest changes occurring in northern high latitudes, consistent with polar amplification. Energy storage is 3-5 times larger in the deep than in the shallow model and increases progressively with additional soil layers until the model depth reaches about 200 m. While the contents of Part I focus on the sensitivity of subsurface thermodynamics to enlarging the space for energy, Part II addresses the sensitivity to changing the space for water and improving hydrological and phase-change interactions., Ministerio de Economía y Competitividad (MINECO), BMBF Federal Ministry of Education & Research, Scientific Steering Committee (WLA), Depto. de Física de la Tierra y Astrofísica, Fac. de Ciencias Físicas, TRUE, pub
- Published
- 2021
18. Forest cover change analysis based on temporal gradients of the vertical structure and density
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Antonio Maria Garcia Tommaselli, Eija Honkavaara, Nilton Nobuhiro Imai, Rorai Pereira Martins-Neto, Adilson Berveglieri, Gabriela Takahashi Miyoshi, Universidade Estadual Paulista (Unesp), and National Land Survey of Finland
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0106 biological sciences ,Canopy ,Ecology ,Temporal gradient ,Forest management ,General Decision Sciences ,010501 environmental sciences ,Atmospheric sciences ,Tropical forest ,010603 evolutionary biology ,01 natural sciences ,Tree (data structure) ,Photogrammetry ,Histogram ,Historical image ,Environmental science ,Cover (algebra) ,Cover change ,Categorical variable ,Ecology, Evolution, Behavior and Systematics ,QH540-549.5 ,0105 earth and related environmental sciences - Abstract
Made available in DSpace on 2021-06-25T10:56:06Z (GMT). No. of bitstreams: 0 Previous issue date: 2021-07-01 Canopy height is an important attribute that allows characterizing the forest vertical structure and analyze changes in vegetation cover over time. The objective of this study is to develop an approach for a spatio-temporal analysis of the tropical forest canopy using multi-temporal photogrammetric images. The datasets based on film and digital cameras are used to generate canopy height models and extract structural variables (tree height, relative variance between tree heights, and density of higher trees in the upper canopy). The combination of these variables is used in the analysis. Each variable is segmented into ordinal categorical classes in its respective dataset with temporal class gradients being obtained between the periods of the multi-temporal datasets. Experiments were conducted in a tropical forest under regeneration and with diversity of tree species in different successional stages. Three sets of images (years 1978, 2010, and 2017) were used for analyzing canopy cover changes. A classification based on histograms of gradient classes indicated and quantified the most frequent behavior of the canopy over time. The results showed that the most significant variations in cover changes could be explained by 13 classes of temporal gradients, which described 88% of the canopy. This classification was validated with field data collected in sample plots. From the results, it can be concluded that the proposed approach provides accurate assessments of the spatio-temporal canopy cover changes for forest management. Department of Cartography UNESP - Universidade Estadual Paulista, Rua Roberto Simonsen 305 Department of Remote Sensing and Photogrammetry Finnish Geodetic Institute FGI National Land Survey of Finland Department of Cartography UNESP - Universidade Estadual Paulista, Rua Roberto Simonsen 305
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- 2021
19. Large historical carbon emissions from cultivated northern peatlands
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Qiu, Chunjing, Ciais, Philippe, Zhu, Dan, Guenet, Bertrand, Peng, Shushi, Petrescu, Ana Maria Roxana, Petrescu, Roxana, Lauerwald, Ronny, Makowski, David, Gallego-Sala, Angela, Charman, Dan, Brewer, Simon, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Mathématiques et Informatique Appliquées (MIA-Paris), Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)-AgroParisTech-Université Paris-Saclay, Universitat Autònoma de Barcelona (UAB), Laboratoire de géologie de l'ENS (LGENS), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Peking University [Beijing], Vrije Universiteit Brussel (VUB), Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), AgroParisTech-Université Paris-Saclay-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), University of Exeter, University of Utah, GENCI-TGCC 2020A0070106328, UK Research & Innovation (UKRI)Natural Environment Research Council (NERC)NE/I012915/1, ANR-16-CONV-0003,CLAND,CLAND : Changement climatique et usage des terres(2016), European Project: 610028,EC:FP7:ERC,ERC-2013-SyG,IMBALANCE-P(2014), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Mathématiques et Informatique Appliquées (MIA Paris-Saclay), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Earth and Climate, Franche-Comté Électronique Mécanique, Thermique et Optique - Sciences et Technologies (UMR 6174) (FEMTO-ST), Université de Technologie de Belfort-Montbeliard (UTBM)-Ecole Nationale Supérieure de Mécanique et des Microtechniques (ENSMM)-Université de Franche-Comté (UFC), Université Bourgogne Franche-Comté [COMUE] (UBFC)-Université Bourgogne Franche-Comté [COMUE] (UBFC)-Centre National de la Recherche Scientifique (CNRS), Vrije Universiteit Amsterdam [Amsterdam] (VU), Université libre de Bruxelles (ULB), University of Bristol [Bristol], and College of Life and Environmental Sciences [Exeter]
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DYNAMICS ,GREENHOUSE-GAS EMISSIONS ,CH4 ,Ecology ,METHANE FLUXES ,DRAINAGE ,[SDE.MCG]Environmental Sciences/Global Changes ,SciAdv r-articles ,PEAT SOILS ,COVER CHANGE ,[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology ,LAND-SURFACE MODEL ,[SDE]Environmental Sciences ,SDG 13 - Climate Action ,CO2 ,ORGANIC SOILS ,Research Articles ,Research Article - Abstract
Crop cultivation of northern peatlands emitted large amount of CO2 over the period 850–2010., When a peatland is drained and cultivated, it behaves as a notable source of CO2. However, we lack temporally and spatially explicit estimates of carbon losses from cultivated peatlands. Using a process-based land surface model that explicitly includes representation of peatland processes, we estimate that northern peatlands converted to croplands emitted 72 Pg C over 850–2010, with 45% of this source having occurred before 1750. This source surpassed the carbon accumulation by high-latitude undisturbed peatlands (36 to 47 Pg C). Carbon losses from the cultivation of northern peatlands are omitted in previous land-use emission assessments. Adding this ignored historical land-use emission implies an 18% larger terrestrial carbon storage since 1750 to close the historical global carbon budget. We also show that carbon emission per unit area decrease with time since drainage, suggesting that time since drainage should be accounted for in inventories to refine land-use emissions from cultivated peatlands.
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- 2021
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20. Impacts of Historical Land Use/Cover Change (1980–2015) on Summer Climate in the Aral Sea Region
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Miao Zhang, Piet Termonia, Friday Uchenna Ochege, Philippe De Maeyer, Huili He, Chaofan Li, Geping Luo, Peng Cai, and Rafiq Hamdi
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summer ,Atmospheric Science ,010504 meteorology & atmospheric sciences ,Energy balance ,ALARO‐ ,Aral Sea region ,Sensible heat ,Atmospheric sciences ,01 natural sciences ,Latent heat ,Earth and Planetary Sciences (miscellaneous) ,Precipitation ,surface energy fluxes ,0105 earth and related environmental sciences ,Diurnal temperature variation ,Global warming ,land use ,SURFEX regional climate model ,cover change ,Water resources ,m temperature ,Geophysics ,summer 2  ,Space and Planetary Science ,Earth and Environmental Sciences ,summer precipitation ,Environmental science ,Climate model - Abstract
In the Aral Sea region, significant land use/cover change (LUCC) occurred in the past 50 years, especially the shrinking of Aral Sea due to unreasonable usage of water resources under intensified agricultural activities. However, to date, regional climatic feedbacks on fine-scale exerted by such LUCC in Central Asia have not been studied clearly. In this study, ALARO-SURFEX regional climate model was used to perform climate simulations under different underlying surface scenarios with 4 km spatial resolution to explore the impacts of historical LUCC on summer climate during 1980-2015. Our results show that compared to default land surface conditions, the modified ones improved the model's ability in simulating temperature, precipitation, and surface energy fluxes. During the period 1980-2015, LUCC accelerated the warming trend, reduced the summer precipitation and altered allocation of surface energy fluxes. Exposed dry bottom of Aral Sea has undergone the most conspicuous warming, which caused increase of the 2 m maximum temperature, average temperature, and diurnal temperature range by 2.56 +/- 0.88 degrees C, 1.04 +/- 0.53 degrees C, and 3.42 +/- 1.10 degrees C, respectively, while minimum temperature decrease by 1.14 +/- 0.56 degrees C. The summer precipitation (mainly convective precipitation) decreased by about 2.33 mm overlay the exposed dry bottom of Aral Sea and approximately 400 km "buffer" region in its eastern side. Additionally, the energy balance changed as follows: -47.9, 50.19, -78.67, and -23.72 W m(-2) for net radiation, sensible heat, latent heat, and soil heat, respectively. Quantified contribution of LUCC on regional climate provides useful information for developing mitigation and adaption strategies under the global warming threat.
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- 2021
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21. Asymmetric patterns and temporal changes in phenology-based seasonal gross carbon uptake of global terrestrial ecosystems
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Wang Lanhui, Tian Feng, Huang Ke, Wang Yuhang, Wu Zhendong, Fensholt, Rasmus, Wang Lanhui, Tian Feng, Huang Ke, Wang Yuhang, Wu Zhendong, and Fensholt, Rasmus
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- 2020
22. PATRONES DE LA VEGETACIÓN Y TIPOS DE USO DE LA TIERRA EN EL VALLE DEL PATÍA.
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Vergara Varela, Hernando
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Vegetation of dry forest ecosystem of the Patia Valley located in the department of Cauca has been altered and replaced by crops and pastures. The forest remnants were characterized in terms of their structure and floristic composition at altitudes between 500 and 800 m. This study evaluated changes in land cover using aerial photographs and satellite image as input to produce land cover maps in order to assess changes associated with land use types . Data were analyzed by multivariate methods using the TWINSPAN program to produce a vegetation classification, identifying six vegetation structure types and six floristic types. The floristic gradient thrown by the program describes structural types, ranging from forests to shrublands and grasslands. Successional plant communities reflect conditions of the fragments, Citharexylum kunthianum community contrasts with riparian forests determined by Eugenia sp the dominant specie in disturbed areas. Handroanthus chrysanthus community shows a transition to xerophyte vegetation of the south of Colombia. Land use types and land cover classes have remained since 1961, increasing pasture cover. Tropical dry forests are reduced in its structure, considering that forests are disturbed. In the long history of the land use and disturbance of this area, a reduction in forest fragments is evident, social and economic factors are a force for a change in plant communities in rural areas. [ABSTRACT FROM AUTHOR]
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- 2015
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23. The structure of the mangrove forests of Kiunga-Pate Island conservancies in Kenya are shaped by selective harvesting and natural mortalities.
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Okello, Judith A., Osuka, Kennedy E., Maina, George W., Mbugua, James, and Samoilys, Melita A.
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Lamu archipelago is endowed with rich biodiversity including Kenya's largest continuous acreage of mangroves (approx. 33,000 ha) among other ecosystems making it a hotspot for management and conservation efforts. Yet, the involvement of the local community in management in this area is still in its infancy, with threats from large-scale developments, population growth, and climate change on the rise. Here, the structural status of the mangroves around Pate Island and Kiunga Marine National Reserve (KMNR) was assessed and information applied to guide and promote community-based conservation, as well as the development of the national mangrove management plan. Stratified and random spot sampling was used to collect vegetation data and mapping undertaken to estimate the mangrove cover change between 1995 and 2014. There was a loss in mangrove cover of up to 22.6% over 19years. A substantial loss was associated with illegal selective harvesting outside the KMNR, some clear-cutting to pave way for large-scale development and natural mortality of overgrown mature trees within the KMNR. In particular, natural mortality was found to hinder natural regeneration within the KMNR. The results however showed a generally stable system with potentially sustainable levels of natural regeneration and recoveries in isolated patches. These results reveal two management actions: raising awareness of mangrove ecosystems' ecological value and controlling old-growth harvesting in the KMNR to facilitate natural regeneration and development of young vigorous forest through gap creation. This information provides a strong foundation for conservation planning including future mangrove restoration and conservation activities. A comprehensive coordinated conservation strategy that links conservation to communities, livelihoods, and governance frameworks is recommended. • Loss in mangrove cover of up to 22.6% reported over a period of 19 years. • Natural regeneration potentially sufficient to sustain the forest but selective harvesting led to structural imbalance. • Natural mortality of mainly overgrown mature trees noted within the Reserve. • Need for a well-coordinated strategy linking conservation to communities, livelihoods and governance framework. [ABSTRACT FROM AUTHOR]
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- 2022
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24. Land use/cover change and its impact on soil carbon in eastern part of Qinghai Plateau in near 10 years.
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Zeng Yongnian, Chen Xiaoling, and Jin Wenping
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In recent years, the rapid changes of land use pattern have taken placed in the eastern part of Qinghai plateau due to human activities. Therefore, it is of great significance to reveal the relationship between the regional land cover change and consequently impact on soil carbon. Using such relationship, we can optimize land use structure and spatial configuration in order to improve the regional environment and promote its sustainable development. It is reported in literature that the land use/cover change is one of the main factors which may influence the regional carbon balance, and it can change the ecosystem carbon cycle and alter the regional even global carbon balance among different carbon pools. Based on the multi-temporal remote sensing data from Landsat TM, in this paper, we used the agriculture area of Haidong city located in the eastern part of Qinghai Plateau as a case study to investigate land use/cover change and consequently its impact on the regional carbon balance. The research was to be used as a reference for balancing the relationship among economic development, eco-system protection and cultivated land conservation and pursuit of low-carbon land use. Firstly, the intensity and directions of different types of land use pattern on eastern region of Qinghai Plateau in the last decade was analyzed by using change of land use intensity index. Then, carbon effect caused by eight main types of land use change including: cultivated land into forest land, forest land into cultivated land, cultivated land into grass, grass into cultivated land, forest land into grass, grass into forest land, cultivated land into construction land and construction land into cultivated land was studied. The results indicated that the implement of "Grain for Green Project" and progress made from the Western Development Strategy from the central government significant changed land use/cover in Haidong from 1999 to 2009. There were three kinds of land use types including forest, construction land and unutilized land, which increased by 67%, 56% and 1.14%, respectively and two types including cultivated land and grassland which decreased by 30% and 12%, respectively. Besides, the decrease of cultivated land was caused by construction land expansion and cultivated land conversion to different land uses. As a convention, the land use type, such as cultivated, forests and grass, are mainly considered as carbon sinks, while construction land is considered to be carbon source for emissions. By use of the method of ecological system type, we estimated the incremental trend effect on carbon in the studied area from 1999 to 2009, which indicated that the increment of carbon emission was higher than carbon sink by 2.4041 million tons. Especially, the expansion of construction land has caused carbon emission 3.7360 million tons. The positive impact on ecosystem from land conversion to non-cultivated land increased carbon sinks by 1.5604 million tons and the negative impact on ecosystem decreased carbon sinks by 0.2285 million tons. In the last 10 years, the increment of carbon emission caused by land use/cover changes exceeded the carbon sink which indicated that land use changes driven by natural and human factors jointly can exercise remarkable impact on carbon balance and sustainable development in eastern region of Qinghai Plateau. [ABSTRACT FROM AUTHOR]
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- 2014
25. Mapping forest structural heterogeneity of tropical montane forest remnants from airborne laser scanning and Landsat time series
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Janne Heiskanen, Ruben Valbuena, Petri Pellikka, Hari Adhikari, Helsinki Institute of Sustainability Science (HELSUS), Earth Change Observation Laboratory (ECHOLAB), Department of Geosciences and Geography, Institute for Atmospheric and Earth System Research (INAR), and Global Atmosphere-Earth surface feedbacks
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0106 biological sciences ,TOPOGRAPHIC NORMALIZATION ,LiDAR ,Biodiversity ,General Decision Sciences ,010501 environmental sciences ,010603 evolutionary biology ,01 natural sciences ,Gini coefficient ,Altitude ,Forest structure ,Spectral-temporal metrics ,BOREAL FORESTS ,MANAGEMENT ,Water cycle ,Cypress ,Ecology, Evolution, Behavior and Systematics ,INDEX ,0105 earth and related environmental sciences ,Tree canopy ,4112 Forestry ,Ecology ,Taiga ,SPECIES-DIVERSITY ,Species diversity ,Forestry ,EASTERN ARC MOUNTAINS ,15. Life on land ,Eucalyptus ,COVER CHANGE ,Africa ,Environmental science ,BIODIVERSITY - Abstract
Tropical montane forests are important reservoirs of carbon and biodiversity and have a central role in the hydrological cycle. They are, however, very fragmented and degraded, leaving isolated remnants across the landscape. These montane forest remnants have considerable differences in forest structure, depending on factors such as tree species composition and degree of forest degradation. Our objectives were (1) to analyse the reliability of airborne laser scanning (ALS) in modelling forest structural heterogeneity, as described by the Gini coefficient (GC) of tree size inequality; (2) to determine whether models are improved by including tree species-sensitive spectral-temporal metrics from the Landsat time series (LTS); and (3) to evaluate differences between three forest remnants and different forest types using the resulting maps of predicted GC. The study area was situated in Taita Hills, Kenya, where indigenous montane forests have been partly replaced by single-species plantations. The data included field measurements from 85 sample plots and two ALS data sets with different pulse densities (9.6 and 3.1 pulses m(-2)). GC was modeled using beta regression. We found that GC was predicted more accurately by the ALS data set with a higher point density (a cross-validated relative root mean squared error (rRMSE(CV)) 13.9%) compared to ALS data set with lower point density (rRMSE(CV) 15.1%). Furthermore, important synergies exist between ALS and LTS metrics. When combining ALS and LTS metrics, rRMSE(CV) was improved to 12.5% and 13.0%, respectively. Therefore, if the LTS metrics are included in models, ALS data with lower pulse density are sufficient to yield similar accuracy to more expensive, higher pulse density data acquired from the lower altitude. In Ngangao and Yale, forest canopy has multiple layers of variable tree sizes, whereas elfin forests in Vuria are of more equal tree size, and the GC value ranges of the indigenous forests are 0.42-0.71, 0.20-0.74, and 0.17-0.76, respectively. The single-species plantations of cypress and pine showed lower values of GC than indigenous forests located in the same remnants in Yale, whereas Eucalyptus plantations showed GC values more similar to the indigenous forests. These results show the usefulness of GC maps for identifying and separating forest types as well as for assessing their distinctive ecologies.
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- 2020
26. Attribution Assessment and Prediction of Runoff Change in the Han River Basin, China
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Mengru Wei, Zhe Yuan, Jijun Xu, Mengqi Shi, and Xin Wen
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China ,Han River Basin ,Budyko framework ,runoff change ,land use ,cover change ,Rivers ,Climate Change ,Health, Toxicology and Mutagenesis ,Water Movements ,Water Resources ,Public Health, Environmental and Occupational Health ,Hydrology - Abstract
The ecological environment and water resources of the Han River Basin (HRB) are incredibly susceptible to global warming. Naturally, the analysis of future runoff in HRB is believed to offer a theoretical basis for water resources management and ecological protection in HRB. The purpose of this study is to investigate and forecast the effects of climate change and land use change on runoff in the HRB. This study uses CMIP6 data to simulate three future climate change scenarios (SSP126, SSP245 and SSP585) for changes in precipitation and temperature, a CA-Markov model to simulate future land use change scenarios, and the Budyko framework to predict future runoff changes. The results show that: (1) Between 1974 and 2014, annual runoff (R) and annual precipitation (P) in the HRB decline not so significantly with a rate of 1.3673 mm/a and 1.2709 mm/a, while maximum temperature (Tmax) and minimum temperature (Tmin) and potential evapotranspiration (E0) show a non-significantly increasing trend with 0.0296 °C/a, 0.0204 °C/a and 1.3313 mm/a, respectively. Precipitation is considered as main contributor to the decline in Han River runoff, accounting for 54.1%. (2) In the HRB, overall precipitation and temperature are estimated to rise in the coming years, with all other hydrological variables. The comparison of precipitation rise under each scenario is as follows: SSP126 scenario > SSP585 scenario > SSP245 scenario. The comparison of the temperature increase under each scenario is as follows: SSP585 scenario > SSP245 scenario > SSP126 scenario. (3) In the HRB, farmland and grassland land will continue to decline in the future. The amount of forest acreage is projected to decline but not so significantly. (4) The future runoff of the HRB shows an increasing trend, and the future runoff varies in different scenarios and periods. Under the land use scenarios of maintaining LUCC1992–2014 and LUCC2040 and LUCC2060, the R change rates in 2015–2040 are 8.27–25.47% and −8.04–19.35%, respectively, and the R in 2040–2060 are 2.09–13.66% and 19.35–31.52%. At the same time, it is very likely to overestimate the future runoff of the HRB without considering the changes in the land use data of the underlying surface in the future.
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- 2022
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27. Hydrological dynamics of tropical streams on a gradient of land-use disturbance and recovery: A multi-catchment experiment
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Kawi Bidin, Glen Reynolds, Anand Nainar, Nobuaki Tanaka, Rory P. D. Walsh, Kogila Vani Annammala, Robert M. Ewers, and Rainforest Research Sdn Bhd
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Technology ,Engineering, Civil ,Environmental Engineering ,010504 meteorology & atmospheric sciences ,OIL PALM ,SEGAMA RAIN-FOREST ,0208 environmental biotechnology ,Drainage basin ,Streamflow ,02 engineering and technology ,Rainforest ,STREAMS ,MALAYSIAN BORNEO ,01 natural sciences ,Engineering ,Tropical ,RUNOFF RESPONSE ,MD Multidisciplinary ,SUSPENDED SEDIMENT DYNAMICS ,Forest ,Geosciences, Multidisciplinary ,OVERLAND-FLOW ,0105 earth and related environmental sciences ,Water Science and Technology ,Hydrology ,geography ,Science & Technology ,Baseflow ,geography.geographical_feature_category ,WATER-YIELD ,NORTHERN THAILAND ,Logging ,Geology ,Storm ,020801 environmental engineering ,COVER CHANGE ,DANUM-VALLEY ,Physical Sciences ,Soil water ,Water Resources ,Environmental science ,Surface runoff - Abstract
Although erosional impacts of rainforest logging are well established, changes in hydrological dynamics have been less explored especially in the post-logging recovery phase following repeat-logging cycles and mature phase of oil palm plantation cycles. This study addresses this gap by comparing hydrological characteristics of five catchments in a steep land area of Sabah, Malaysian Borneo on a gradient of disturbance and recovery – twice-logged forest, 22 years recovery (LF2); multiple-logged forest, 8 years recovery (LF3); mature oil palm, 20 years old (OP); and two primary forests (PF and VJR) as controls. Each catchment was instrumented with water depth (converted to discharge), conductivity, temperature, and turbidity sensors, and a raingauge connected to a solar-powered datalogger recording data at 5-minute intervals from November 2011 to August 2013. Data were analysed via the flow-duration curve (FDC) supplemented by the runoff coefficient (RR) and coefficient of variation in discharge (QVAR) for aggregated characteristics, as well as via a combination of the Dunn's test and multiple-regression at the storm event scale for focused hydrological dynamics. Results show that OP is characterised by a relatively low RR (0.357) but with high responsiveness during storm events and very low baseflow (38.4% of total discharge). Discharge in the LF3 (RR = 0.796) is always the highest while having an intermediate level of responsiveness. LF2 with longer-term recovery shown a reduction in terms of discharge (RR = 0.640). Being the benchmark, the undisturbed forest (PF) has the most buffered storm response with the highest baseflow (67.9% of total discharge). Stormflow and baseflow are anomalously high and low respectively in the near-primary VJR catchment, but this probably reflects the shallow soils and short-stature rainforest associated with its igneous and metamorphic lithology. From a management aspect, although hydrological recovery is more advanced in the 22 years than in the 8-years post-logging catchment, full recovery is yet to be achieved and might be hastened by enrichment planting of the degraded forest. The low baseflow and flashy nature of the mature oil palm have major implications for downstream water supply in ENSO periods and flooding in La Nina periods. Steep lands in the humid tropics are best avoided from any form of landscape disturbance.
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- 2018
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28. Assessing the effectiveness of regulation to protect threatened forests
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Martine Maron, Leonie Seabrook, Jonathan R. Rhodes, and Lorenzo Cattarino
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0106 biological sciences ,Vegetation Management Act ,AUSTRALIA ,QUEENSLAND ,010504 meteorology & atmospheric sciences ,Biodiversity & Conservation ,Legislation ,CONSERVATION ,05 Environmental Sciences ,Forest management ,Biodiversity ,Environmental Sciences & Ecology ,ECOSYSTEM SERVICES ,010603 evolutionary biology ,01 natural sciences ,Ecosystem services ,Policy evaluation ,Environmental protection ,DRIVERS ,Clearing ,Deforestation ,Path analysis ,Forest protection ,EMISSIONS ,Ecology, Evolution, Behavior and Systematics ,0105 earth and related environmental sciences ,Nature and Landscape Conservation ,Science & Technology ,Ecology ,Agroforestry ,06 Biological Sciences ,15. Life on land ,Forestry law ,POLICY ,COVER CHANGE ,Incentive ,Threatened species ,Biodiversity Conservation ,BIODIVERSITY ,07 Agricultural And Veterinary Sciences ,Life Sciences & Biomedicine ,Environmental Sciences - Abstract
Deforestation threatens the earth's biodiversity and the ecosystem services upon which humans depend. Formal regulation is a key mechanism by which governments seek to protect forests. However, whether regulation can effectively protect remaining areas of the most threatened and most heavily cleared forests is unknown. We addressed this question using forest loss data for Queensland, Australia between 2000 and 2014 under existing vegetation clearing regulation (Vegetation Management Act 1999). This regulation is specifically designed to provide the greatest protection for threatened forest types that have already lost the greatest amount of their original extent. Importantly, enforcement and governance of this regulation is relatively strong allowing an assessment of regulation design. We applied path analysis to model the direct and indirect effects (mediated by variables representing deforestation pressure) of forest protection level on clearing rates. There was strong evidence for a decline in clearing rates over time, except of clearing for non-agricultural purposes. However, threatened forest types, which have already lost > 70% of their original extent and should have the greatest level of protection under the regulation, continue to be cleared 2.7–2.9 times faster than non-threatened forest types. There was also little evidence that the regulation has driven greater reductions over time in the clearing rates of threatened versus non-threatened forests types. There was much greater support for the indirect than direct effect of protection level. This is because protection level was correlated with variables associated with deforestation pressure, resulting in higher clearing rates for threatened compared to non-threatened forest types. We hypothesise that this arises because the additional protection afforded to threatened relative to non-threatened forests is insufficient to counter the continuing higher level of deforestation pressure on threatened forests. We argue that a potential solution is to build explicit targets for forest retention into regulation, below which no further forest loss is permitted. This could be combined with spatially targeted enforcement and incentive strategies where threats are highest.
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- 2017
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29. Resilience in Quaking Aspen: Recent advances and future needs.
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Rogers, Paul C., Eisenberg, Cristina, and St. Clair, Samuel B.
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POPULUS tremuloides ,FOREST ecology ,POPULATION biology ,LIVESTOCK systems ,GRAZING & the environment ,DISCUSSION - Abstract
Abstract: Quaking Aspen (Populus tremuloides) sustainability is a topic of intense interest in forest ecology. Reports range from declines to persisting or increasing coverage in some areas. Moreover, there is little agreement on ultimate factors driving changes. Low aspen recruitment has been attributed to climate patterns, past management, herbivore increases, competitive interactions with conifers, predator and beaver extirpation, and livestock grazing. Several of these potential causes result from direct or indirect actions of human agency. On June 27–28, 2012 a group of leading aspen ecologists from diverse backgrounds convened at the High Lonesome Ranch in western Colorado to address the state of aspen science under the title, Resilience in Quaking Aspen: restoring ecosystem processes through applied science. The purposes of this meeting were to: (a) present disciplinary updates on recent developments; (b) focus our collective understanding on determining key research gaps; and, to the extent possible, (c) develop a plan to communicate both advances and science gaps to wider audiences. Presentations and group discussions were framed mainly in the geographic context of the western US. The symposium addressed dual central themes—historical aspen cover change and ungulate herbivory—both of which have important ramifications for future aspen resilience. We also found emergent themes in disturbance, climate work, and genetic innovation. This paper presents a brief review of the state of aspen science and a synopsis of issues and needs identified at the symposium. Detailed treatments of topics mentioned here are found in accompanying articles of this volume. A key recommendation from researchers here is that there are many “aspen types” and novel, landscape- or aspen type-specific, approaches will be required to appropriately address this regional diversity. We further emphasize needed interdisciplinary work addressing changing climates, altered disturbance patterns, intensive herbivory, and human drivers of ecological change. [Copyright &y& Elsevier]
- Published
- 2013
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30. NATURAL AND ARTIFICIALLY WATER FLUX RATIO RESEARCH IN ARID INLAND RIVER BASIN, CHINA.
- Author
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Guang Yang, Xin-lin He, and Tiegang Zheng
- Abstract
Natural water circulation is closely related to artificially water cycle and their hydraulic connection is of great significance to the sustainable use of water resources. Based on the binary water cycle theory of natural - artificial and watershed water balance as a guide, Manas river basin was studied water cycle model (ABMBC), where interaction mechanism in the binary mode was analyzed. Calculation for water cycle flux in the changing environment of Manas river basin was combined with the calculation method for GIS to identify the reasonable proportion flux between natural water circulation flux and artificial cycle flux in Manasi river basin. Water flux analysis for different years combined with different ecological environment and economic development, revealed that the natural and artificial water flux coordination proportion was 33:65. Therefore, in order to maintain and improve Manasi River watershed ecological environment, a volume of approximately 1.0 to 1.4 billion m³ should be discharged to the watershed downstream each year. [ABSTRACT FROM AUTHOR]
- Published
- 2012
31. On the burrowing impacts of ice rats Otomys sloggetti robertsi at a wetland fringe in the Afro-alpine zone, Lesotho.
- Author
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Grab, Stefan
- Subjects
- *
RATS , *HABITATS , *WETLANDS , *BIOENGINEERING - Abstract
Recent work has indicated that the southern African ice rat (Otomys sloggetti robertsi) is responsible for negative habitat change due to its foraging and burrowing activities in the Lesotho Highlands. Previous work has only focused on short-term ( ≤ 1 year) monitoring and thus the impact of such rodent activity over longer temporal scales remains unknown. To this end, the current study evaluates vegetation cover and O. s. robertsi's burrowing over a 10-year period (1998–2009) across a portion of a wetland fringe/wetland in eastern Lesotho. A 6 m × 11 m plot was established in 1998 and marked out with permanent stakes. Percentage cover and number of tunnels were recorded, with repeat measurements taken in 2001, 2005 and 2009. The findings indicate an overall 69.2% increase in vegetation cover and associated 71% decrease in burrow densities between 1998 and 2009. The area monitored closest to the wetland fringe recorded the most substantial burrow density decrease (by 80%) and vegetation recovery (by 43%) within a three-year period from 1998 to 2001. With a slight shift of burrow density increases towards the wetland centre, particularly between 2001 and 2005, the standard deviation of burrow density (per m2) from the wetland periphery towards the wetland centre had decreased from 1.25 to 0.32 over the 10-year period. It is proposed that the environmental influence of O. s. robertsi may be less dramatic at some landscape and longer temporal (i.e. years rather than months) scales due to spatial shifts of colonies, bioengineering and rapid vegetation recovery at abandoned, formerly ‘degraded’ burrow sites. [ABSTRACT FROM AUTHOR]
- Published
- 2012
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32. Comparing measurements methods of carbon dioxide fluxes in a soil sequence under land use and cover change in North Eastern Spain
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Emran, Mohamed, Gispert, Maria, and Pardini, Giovanni
- Subjects
- *
CARBON in soils , *LAND use , *LAND cover , *SOIL respiration , *BIOMASS , *SOIL moisture , *INFRARED detectors , *CARBON sequestration - Abstract
Abstract: Carbon dioxide measurements from soil surface may indicate the potential for soil respiration and carbon consumption according to microbial biomass and root activity. These processes may be influenced by land use and cover change, and abandonment especially in the upper soil organic layer. Seven environments from cultivation to late abandonment, with the same soil type classified as Lithic Xerorthent, were tested to ascertain the respiration capacity according to the current use and cover, and to establish the ability to preserve and eventually increase the organic matter pools after abandonment. Given the importance of carbon dioxide measurements at soil surface, a comparison between the classic soda lime method (SL) and a rapid method based on infrared sensor analyzer (IR) was performed from autumn 2008 to autumn 2009 in the field. The field measurements of CO2 proved significant correlations between the values from the two techniques under the same natural conditions and along the period of observation. However, the values of CO2 measured by the soda lime method were always higher than those obtained by the infrared analyzer. This pattern was attributed to the difference in time of measurement, larger in the former method, and type of measurement technique. Despite that the trend of measured CO2 values was rather similar along the year. On average, the highest values of CO2 emission in the field were recorded in the warmest periods of the year and with soil surface moisture not lower than 3% independently on the method used. High soil surface temperature with soil moisture below 3% decreased drastically the CO2 production from the dry soil. The cultivated environments and soil under forests have resulted higher CO2 producers than abandoned soils depending on the age of abandonment, climatic conditions, and within abandonment perturbations. Those abandoned soils preserved by perturbations like wildfire showed a higher potential for accumulating organic carbon, as indicated by the lowest emission of CO2 with respect to SOC content, during the period of observation. Results demonstrated the reliability of the methods used to evaluate the soil carbon dioxide production capacity and allowed to classify through environments with increasing potential for carbon sequestration. The classification was rather similar by using both methods indicating a higher susceptibility to carbon loss in the following order: soil under Vines (V)>under Olives (O)>under Pine trees (PI)>under Cork Trees (S)>under Pasture (PR)>under Cistus scrub (MC)>under Erica scrub (MB) by using the SL method and V>O>PI>S>MC>MB>PR by using the IR method. Indications about the need of management of abandoned areas were also considered in order to recover the landscape heterogeneity. [Copyright &y& Elsevier]
- Published
- 2012
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33. The effect of temperature on growth and competition between Sphagnum species.
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Breeuwer, Angela, Heijmans, Monique M. P. D., Robroek, Bjorn J. M., Berendse, Frank, and Green, Allan
- Subjects
- *
PEAT mosses , *MOSSES , *WETLAND animals , *GLOBAL warming , *GLOBAL temperature changes , *GREENHOUSE effect - Abstract
Peat bogs play a large role in the global sequestration of C, and are often dominated by different Sphagnum species. Therefore, it is crucial to understand how Sphagnum vegetation in peat bogs will respond to global warming. We performed a greenhouse experiment to study the effect of four temperature treatments (11.2, 14.7, 18.0 and 21.4°C) on the growth of four Sphagnum species: S. fuscum and S. balticum from a site in northern Sweden and S. magellanicum and S. cuspidatum from a site in southern Sweden. In addition, three combinations of these species were made to study the effect of temperature on competition. We found that all species increased their height increment and biomass production with an increase in temperature, while bulk densities were lower at higher temperatures. The hollow species S. cuspidatum was the least responsive species, whereas the hummock species S. fuscum increased biomass production 13-fold from the lowest to the highest temperature treatment in monocultures. Nutrient concentrations were higher at higher temperatures, especially N concentrations of S. fuscum and S. balticum increased compared to field values. Competition between S. cuspidatum and S. magellanicum was not influenced by temperature. The mixtures of S. balticum with S. fuscum and S. balticum with S. magellanicum showed that S. balticum was the stronger competitor, but it lost competitive advantage in the highest temperature treatment. These findings suggest that species abundances will shift in response to global warming, particularly at northern sites where hollow species will lose competitive strength relative to hummock species and southern species. [ABSTRACT FROM AUTHOR]
- Published
- 2008
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34. Land use change and gully erosion in the Piedmont region of South Carolina.
- Author
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Galang, M. A., Markewitz, D., Morris, L. A., and Bussell, P.
- Subjects
- *
LAND use , *EROSION , *ARROYOS , *FOREST reserves , *SEDIMENT transport - Abstract
Land use change played an important role in the formation of gullies present today in the Piedmont of the Southeastern United States. Forested areas that were once cleared to cultivate cotton and consequently gullied are now, once again, covered with forest vegetation. Despite this forest cover, gullies are still considered to be important contributors of sediment to streams, and restoration efforts are still ongoing. However, the data available to assess the extent of gully contributions of sediment are limited. This study assessed the present day stability of these gullies relative to the land use conditions from 1939 to 1999. Based on 1939, 1954, 1970, and 1999 aerial photographs, land areas were classified into those found to be open or cultivated in 1939 that had converted to forest by 1999 (cultivated-to-forested) versus areas that were forested throughout this period (continually forested). An analysis was then conducted that quantified the number and morphological characteristics of gullies in these areas. Characteristics assessed during the field surveys that quantified the presence of recent erosion, such as percent bare soil or forest floor displacement, revealed that the majority of the gullies in both areas are stable. Surprisingly, more frequent (4 vs. 2 per transect), deeper (54 vs. 46 cm), and longer (36 vs. 30 m) gullies were found in the continually forested areas. This equated to a higher estimated average total volume eroded in the continually forested areas (299 m³) compared to the cultivated-to-forested areas (107 m³). It is believed that the continually forested areas, which had steeper average slopes, were cultivated but abandoned prior to 1939 due to severe gully formation. [ABSTRACT FROM AUTHOR]
- Published
- 2007
35. Exploring the future of land use and food security: A new set of global scenarios
- Author
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Mora, Olivier, Le Mouël, Chantal, De Lattre-Gasquet, Marie, Donnars, Catherine, Dumas, Patrice, Réchauchère, Olivier, Brunelle, Thierry, Manceron, Stéphane, Marajo-Petitzon, Elodie, Moreau, Clémence, Barzman, Marco, Forslund, Agneta, Marty, Pauline, Direction de l'Expertise scientifique collective, de la Prospective et des Etudes, Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Structures et Marché Agricoles, Ressources et Territoires (SMART-LERECO), AGROCAMPUS OUEST, Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut national d'enseignement supérieur pour l'agriculture, l'alimentation et l'environnement (Institut Agro)-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad), Centre International de Recherche sur l'Environnement et le Développement (CIRED), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École des hautes études en sciences sociales (EHESS)-AgroParisTech-École des Ponts ParisTech (ENPC)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Département Environnements et Sociétés (Cirad-ES), Département Sciences Sociales, Agriculture et Alimentation, Espace et Environnement (SAE2), Unité de recherche d'Économie et Sociologie Rurales (ESR), Institut National de la Recherche Agronomique (INRA), Acteurs, Ressources et Territoires dans le Développement (UMR ART-Dev), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Université Paul-Valéry - Montpellier 3 (UPVM)-Université de Perpignan Via Domitia (UPVD)-Université de Montpellier (UM)-Centre National de la Recherche Scientifique (CNRS), Université Paris-Saclay-AgroParisTech-École des hautes études en sciences sociales (EHESS)-Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-École des Ponts ParisTech (ENPC)-Centre National de la Recherche Scientifique (CNRS), UAR 1384 Antenne - Délégation à l'Expertise scientifique collective, à la Prospective et aux Etudes, Institut National de la Recherche Agronomique (INRA)-Direction Collégiale (DCOLL)-Antenne - Délégation à l'Expertise scientifique collective, à la Prospective et aux Etudes (Antenne - DEPE), Bureau de Recherches Géologiques et Minières (BRGM) (BRGM), CRIA, Géographie-cités (GC (UMR_8504)), Université Panthéon-Sorbonne (UP1)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Université Panthéon-Sorbonne (UP1)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), and AGROCAMPUS OUEST-Institut National de Recherche pour l’Agriculture, l’Alimentation et l’Environnement (INRAE)
- Subjects
Atmospheric Science ,Physiology ,[SDV]Life Sciences [q-bio] ,Social Sciences ,Global Health ,[SHS]Humanities and Social Sciences ,Food Supply ,systèmes alimentaires ,Land Use ,Medicine and Health Sciences ,Public and Occupational Health ,Challenges ,Climatology ,Utilisation des terres ,Geography ,Agriculture ,Countries ,sécurité alimentaire ,Sustainability ,Health ,Priorities ,[SDE]Environmental Sciences ,Medicine ,Coronavirus Infections ,Research Article ,Terre agricole ,Conservation of Natural Resources ,Livestock ,P40 - Météorologie et climatologie ,Science ,[SDE.MCG]Environmental Sciences/Global Changes ,Climate Change ,Pneumonia, Viral ,Dietary ,Human Geography ,Demand ,Food Quality ,Humans ,Computer Simulation ,Obesity ,Pandemics ,E10 - Économie et politique agricoles ,Cover Change ,Nutrition ,Changement climatique ,Urbanization ,Systems ,Food Consumption ,COVID-19 ,Biology and Life Sciences ,Modèle de simulation ,Diet ,Food ,Earth Sciences ,Physiological Processes ,[SDV.AEN]Life Sciences [q-bio]/Food and Nutrition - Abstract
Facing a growing and more affluent world population, changing climate and finite natural resources, world food systems will have to change in the future. The aim of the Agrimonde-Terra foresight study was to build global scenarios linking land use and food security, with special attention paid to overlooked aspects such as nutrition and health, in order to help explore the possible future of the global food system. In this article, we seek to highlight how the resulting set of scenarios contributes to the debate on land use and food security and enlarges the range of possible futures for the global food system. We highlight four main contributions. Combining a scenario building method based on morphological analysis and quantitative simulations with a tractable and simple biomass balance model, the proposed approach improves transparency and coherence between scenario narratives and quantitative assessment. Agrimonde-Terra's scenarios comprise a wide range of alternative diets, with contrasting underlying nutritional and health issues, which accompany contrasting urbanization and rural transformation processes, both dimensions that are lacking in other sets of global scenarios. Agrimonde-Terra's scenarios share some similarities with existing sets of global scenarios, notably the SSPs, but are usually less optimistic regarding agricultural land expansion up to 2050. Results suggest that changing global diets toward healthier patterns could also help to limit the expansion in agricultural land area. Agrimonde-Terra's scenarios enlarge the scope of possible futures by proposing two pathways that are uncommon in other sets of global scenarios. The first proposes to explore possible reconnection of the food industry and regional production within supranational regional blocs. The second means that we should consider that a 'perfect storm', induced by climate change and an ecological crisis combined with social and economic crises, is still possible. Both scenarios should be part of the debate as the current context of the COVID-19 pandemic shows.
- Published
- 2019
- Full Text
- View/download PDF
36. Reviews and syntheses: influences of landscape structure and land uses on local to regional climate and air quality
- Author
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Raia Silvia Massad, Juliette Lathiére, Mathieu Perrin, Erwan Personne, Marc Stefanon, Patrick Stella, Susanna Strada, Sophie Szopa, Nathalie de Noblet-Ducoudré, Ecologie fonctionnelle et écotoxicologie des agroécosystèmes (ECOSYS), Institut National de la Recherche Agronomique (INRA)-AgroParisTech, Laboratoire des Sciences du Climat et de l'Environnement [Gif-sur-Yvette] (LSCE), Université Paris-Saclay-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Centre National de la Recherche Scientifique (CNRS), Abdus Salam International Centre for Theoretical Physics [Trieste] (ICTP), Sciences pour l'Action et le Développement : Activités, Produits, Territoires (SADAPT), Laboratoire de Météorologie Dynamique (UMR 8539) (LMD), Institut national des sciences de l'Univers (INSU - CNRS)-École polytechnique (X)-École des Ponts ParisTech (ENPC)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)-Département des Géosciences - ENS Paris, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Modelling the Earth Response to Multiple Anthropogenic Interactions and Dynamics (MERMAID), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL), Modélisation du climat (CLIM), Extrèmes : Statistiques, Impacts et Régionalisation (ESTIMR), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS)-Université de Versailles Saint-Quentin-en-Yvelines (UVSQ)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL)
- Subjects
2. Zero hunger ,long-term ,nitrous-oxide ,lcsh:QE1-996.5 ,lcsh:Life ,15. Life on land ,converctive boundary-layer ,[SDE.ES]Environmental Sciences/Environmental and Society ,6. Clean water ,urban heat-island ,cover change ,lcsh:Geology ,lcsh:QH501-531 ,13. Climate action ,near-surface temperature ,[SDU.STU.CL]Sciences of the Universe [physics]/Earth Sciences/Climatology ,lcsh:QH540-549.5 ,oil-palm plantation ,ecosystem services ,soil carbon ,amazomian deforestation ,lcsh:Ecology - Abstract
The atmosphere and the land surface interact in multiple ways, for instance though the radiative-energy balance, the water cycle or the emission-deposition of natural and anthropogenic compounds. By modifying the land surface, land-use and land-cover changes (LULCCs) and land management changes (LMCs) alter the physical, chemical and biological processes of the biosphere and therefore all land-atmosphere interactions, from local to global scales. Through socio-economic drivers and regulatory policies adopted at different levels (local, regional, national or supranational), human activities strongly interfere in the land-atmosphere interactions, at those activities lead to a patchwork of natural, semi-natural, agricultural, urban and semi-urban areas. In this context, urban and peri-urban areas are of particular attention since land transformation can lead to important environmental impacts and affect the health and life of millions of people. The objectives of this review is to synthesize the existing experimental and modelling works that investigate physical, chemical and/or biogeochemical interactions between land surface and the atmosphere mainly in urban or peri-urban landscapes at regional and local scales. In the context of LULCCs, the importance of land-atmosphere interactions for climate and air quality have been analysed in many studies published over the last years, with a large range of spatial and temporal scales investigated. The conclusions from such a synthesis is first that (i) the description of land-use and land-management (e.g. areas concerned, type of crops, whether or not they are irrigated, quantity of fertilizers used and actual seasonality of application), including surface properties and emission sources, is inexistent (or very poor) in global and even more in regional climate models. Not taking into account these characteristics may bias the regional projections used for impact studies. (ii) Land-atmosphere interactions are often specific to the case study analysed; therefore, in this perspective, one can hardly propose general solutions or recommendations. (iii) Adaptation strategies, proposed after the evaluation of climatic impacts on the targeted resource have been derived, but are often biased as they do not account for feedbacks on local/regional climate. (iv) There is space for considering atmospheric chemistry, through land-atmosphere interactions, as a decision parameter for land-management, helping to maintain air quality and supporting ecosystem functioning. (v) There is a lack of an integrated tool, which includes the many different processes of importance in an operational model, to test different land use or land management scenarios at the scale of a territory.
- Published
- 2019
- Full Text
- View/download PDF
37. Attribution Assessment and Prediction of Runoff Change in the Han River Basin, China.
- Author
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Wei M, Yuan Z, Xu J, Shi M, and Wen X
- Subjects
- China, Climate Change, Hydrology, Water Resources, Rivers, Water Movements
- Abstract
The ecological environment and water resources of the Han River Basin (HRB) are incredibly susceptible to global warming. Naturally, the analysis of future runoff in HRB is believed to offer a theoretical basis for water resources management and ecological protection in HRB. The purpose of this study is to investigate and forecast the effects of climate change and land use change on runoff in the HRB. This study uses CMIP6 data to simulate three future climate change scenarios (SSP126, SSP245 and SSP585) for changes in precipitation and temperature, a CA-Markov model to simulate future land use change scenarios, and the Budyko framework to predict future runoff changes. The results show that: (1) Between 1974 and 2014, annual runoff ( R ) and annual precipitation ( P ) in the HRB decline not so significantly with a rate of 1.3673 mm/a and 1.2709 mm/a, while maximum temperature ( Tmax ) and minimum temperature ( Tmin ) and potential evapotranspiration ( E
0 ) show a non-significantly increasing trend with 0.0296 °C/a, 0.0204 °C/a and 1.3313 mm/a, respectively. Precipitation is considered as main contributor to the decline in Han River runoff, accounting for 54.1%. (2) In the HRB, overall precipitation and temperature are estimated to rise in the coming years, with all other hydrological variables. The comparison of precipitation rise under each scenario is as follows: SSP126 scenario > SSP585 scenario > SSP245 scenario. The comparison of the temperature increase under each scenario is as follows: SSP585 scenario > SSP245 scenario > SSP126 scenario. (3) In the HRB, farmland and grassland land will continue to decline in the future. The amount of forest acreage is projected to decline but not so significantly. (4) The future runoff of the HRB shows an increasing trend, and the future runoff varies in different scenarios and periods. Under the land use scenarios of maintaining LUCC1992-2014 and LUCC2040 and LUCC2060, the R change rates in 2015-2040 are 8.27-25.47% and -8.04-19.35%, respectively, and the R in 2040-2060 are 2.09-13.66% and 19.35-31.52%. At the same time, it is very likely to overestimate the future runoff of the HRB without considering the changes in the land use data of the underlying surface in the future.- Published
- 2022
- Full Text
- View/download PDF
38. Forest cover change analysis based on temporal gradients of the vertical structure and density.
- Author
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Berveglieri, Adilson, Imai, Nilton N., M.G. Tommaselli, Antonio, Martins-Neto, Rorai P., Takahashi Miyoshi, Gabriela, and Honkavaara, Eija
- Subjects
- *
FOREST management , *TROPICAL forests , *FOREST regeneration , *FOREST canopies , *TREE height , *DIGITAL cameras - Abstract
Canopy height is an important attribute that allows characterizing the forest vertical structure and analyze changes in vegetation cover over time. The objective of this study is to develop an approach for a spatio-temporal analysis of the tropical forest canopy using multi-temporal photogrammetric images. The datasets based on film and digital cameras are used to generate canopy height models and extract structural variables (tree height, relative variance between tree heights, and density of higher trees in the upper canopy). The combination of these variables is used in the analysis. Each variable is segmented into ordinal categorical classes in its respective dataset with temporal class gradients being obtained between the periods of the multi-temporal datasets. Experiments were conducted in a tropical forest under regeneration and with diversity of tree species in different successional stages. Three sets of images (years 1978, 2010, and 2017) were used for analyzing canopy cover changes. A classification based on histograms of gradient classes indicated and quantified the most frequent behavior of the canopy over time. The results showed that the most significant variations in cover changes could be explained by 13 classes of temporal gradients, which described 88% of the canopy. This classification was validated with field data collected in sample plots. From the results, it can be concluded that the proposed approach provides accurate assessments of the spatio-temporal canopy cover changes for forest management. [ABSTRACT FROM AUTHOR]
- Published
- 2021
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39. Quantifying differences in land use emission estimates implied by definition discrepancies
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Fortunat Joos and Benjamin D. Stocker
- Subjects
FLUX ,0106 biological sciences ,lcsh:Dynamic and structural geology ,010504 meteorology & atmospheric sciences ,Meteorology ,530 Physics ,Land conversion ,01 natural sciences ,lcsh:QE500-639.5 ,Econometrics ,Earth system model ,Land use, land-use change and forestry ,Geosciences, Multidisciplinary ,ATMOSPHERIC CO2 ,lcsh:Science ,550 Earth sciences & geology ,0105 earth and related environmental sciences ,Science & Technology ,CLIMATE-CHANGE ,Land use ,20TH-CENTURY ,010604 marine biology & hydrobiology ,lcsh:QE1-996.5 ,Geology ,Vegetation ,15. Life on land ,CARBON BUDGET ,Bookkeeping ,lcsh:Geology ,Earth system science ,COVER CHANGE ,Climate change mitigation ,13. Climate action ,BALANCE ,Physical Sciences ,FEEDBACKS ,General Earth and Planetary Sciences ,Environmental science ,lcsh:Q ,DEFORESTATION ,DIOXIDE - Abstract
The quantification of CO2 emissions from anthropogenic land use and land use change (eLUC) is essential to understand the drivers of the atmospheric CO2 increase and to inform climate change mitigation policy. Reported values in synthesis reports are commonly derived from different approaches (observation-driven bookkeeping and process-modelling) but recent work has emphasized that inconsistencies between methods may imply substantial differences in eLUC estimates. However, a consistent quantification is lacking and no concise modelling protocol for the separation of primary and secondary components of eLUC has been established. Here, we review differences of eLUC quantification methods and apply an Earth System Model (ESM) of Intermediate Complexity to quantify them. We find that the magnitude of effects due to merely conceptual differences between ESM and offline vegetation model-based quantifications is ~ 20 % for today. Under a future business-as-usual scenario, differences tend to increase further due to slowing land conversion rates and an increasing impact of altered environmental conditions on land-atmosphere fluxes. We establish how coupled Earth System Models may be applied to separate secondary component fluxes of eLUC arising from the replacement of potential C sinks/sources and the land use feedback and show that secondary fluxes derived from offline vegetation models are conceptually and quantitatively not identical to either, nor their sum. Therefore, we argue that synthesis studies should resort to the "least common denominator" of different methods, following the bookkeeping approach where only primary land use emissions are quantified under the assumption of constant environmental boundary conditions.
- Published
- 2018
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40. Urban land-use change:The role of strategic spatial planning
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Sofia Pagliarin, Gaëtan Palka, Simona R. Grădinaru, Eduardo Oliveira, Anna M. Hersperger, Janine Bolliger, Peter H. Verburg, and Environmental Geography
- Subjects
External conditions ,Geography, Planning and Development ,Environmental Studies ,0211 other engineering and technologies ,LANDSCAPE CHANGE ,Social Sciences ,Environmental Sciences & Ecology ,02 engineering and technology ,CELLULAR-AUTOMATA ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,TERRITORIAL GOVERNANCE ,01 natural sciences ,Urban planning ,SWITZERLAND ,SYSTEMS ,PLANS ,Environmental planning ,Spatial planning ,0105 earth and related environmental sciences ,Planning intentions ,Global and Planetary Change ,Governance ,Science & Technology ,DRIVING FORCES ,Ecology ,Geography ,Corporate governance ,021107 urban & regional planning ,Urban land ,POLICY ,Sketch ,Land-change modelling ,SDG 11 - Sustainable Cities and Communities ,COVER CHANGE ,Strategic spatial planning ,Premise ,Plan implementation ,GROWTH ,Business ,Life Sciences & Biomedicine ,Environmental Sciences - Abstract
To date land-change science has devoted little attention to spatial policy and planning in urban landscapes despite the widely accepted premise that planning affects urban land change. This is primarily due to lack of relevant data and an underdeveloped theoretical understanding regarding the impact of spatial planning on urban land change. To be able to better analyse the role of spatial planning in urban development we need to distinguish: 1) the intentions expressed in the plans; 2) the means of implementation of the plans through governance processes and 3) the role of external conditions influencing implementation. Based on a synthesis of the current literature on how spatial planning is implemented in land-change models, and drawing from the literature on planning evaluation, we sketch a research agenda to further develop the understanding of these three components and their interconnections as well as their application in quantitative land-change modelling approaches for urban regions.
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- 2018
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41. Burned area detection based on Landsat time series in savannas of southern Burkina Faso
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Petri Pellikka, Janne Heiskanen, Eduardo Eiji Maeda, Jinxiu Liu, Department of Geosciences and Geography, Earth Change Observation Laboratory (ECHOLAB), TreeD lab - Terrestrial Ecosystem Dynamics, Helsinki Institute of Sustainability Science (HELSUS), Fisheries and Environmental Management Group, and Environmental Sciences
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010504 meteorology & atmospheric sciences ,MODIS IMAGERY ,0211 other engineering and technologies ,Land management ,02 engineering and technology ,Management, Monitoring, Policy and Law ,Spatial distribution ,01 natural sciences ,114 Physical sciences ,Burned area ,FIRE HISTORY ,Harmonic model ,ALGORITHM ,Computers in Earth Sciences ,Time series ,1172 Environmental sciences ,WEST-AFRICA ,021101 geological & geomatics engineering ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Remote sensing ,Global and Planetary Change ,Series (stratigraphy) ,4112 Forestry ,Breakpoint identification ,Local scale ,SPECTRAL INDEXES ,Vegetation ,15. Life on land ,FOREST ,PRODUCTS ,Medium resolution ,COVER CHANGE ,Geography ,MODIS ,CLOUD SHADOW ,13. Climate action ,Landsat time series ,VEGETATION - Abstract
West African savannas are subject to regular fires, which have impacts on vegetation structure, biodiversity and carbon balance. An efficient and accurate mapping of burned area associated with seasonal fires can greatly benefit decision making in land management. Since coarse resolution burned area products cannot meet the accuracy needed for fire management and climate modelling at local scales, the medium resolution Landsat data is a promising alternative for local scale studies. In this study, we developed an algorithm for continuous monitoring of annual burned areas using Landsat time series. The algorithm is based on burned pixel detection using harmonic model fitting with Landsat time series and breakpoint identification in the time series data. This approach was tested in a savanna area in southern Burkina Faso using 281 images acquired between October 2000 and April 2016. An overall accuracy of 79.2% was obtained with balanced omission and commission errors. This represents a significant improvement in comparison with MODIS burned area product (67.6%), which had more omission errors than commission errors, indicating underestimation of the total burned area. By observing the spatial distribution of burned areas, we found that the Landsat based method misclassified cropland and cloud shadows as burned areas due to the similar spectral response, and MODIS burned area product omitted small and fragmented burned areas. The proposed algorithm is flexible and robust against decreased data availability caused by clouds and Landsat 7 missing lines, therefore having a high potential for being applied in other landscapes in future studies.
- Published
- 2018
42. Forest resources of nations in relation to human well-being
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Pekka E. Kauppi, Vilma Sandström, Antti Lipponen, Ecosystems and Environment Research Programme, Pekka Kauppi / Principal Investigator, and Helsinki Institute of Sustainability Science (HELSUS)
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010504 meteorology & atmospheric sciences ,Natural resource economics ,Population Dynamics ,Biodiversity ,Social Sciences ,lcsh:Medicine ,010501 environmental sciences ,Forests ,01 natural sciences ,Trees ,Land Use ,HISTORY ,TRANSITION THEORY ,lcsh:Science ,Finland ,2. Zero hunger ,Multidisciplinary ,Geography ,Ecology ,1. No poverty ,Carbon sink ,Forestry ,Agriculture ,LAND-USE CHANGE ,Terrestrial Environments ,COVER CHANGE ,SATELLITE DATA ,Engineering and Technology ,Research Article ,Conservation of Natural Resources ,Carbon Sequestration ,Environmental Engineering ,Forest Ecology ,Ecological Metrics ,DATABASE ,Forest management ,Biomass (Ecology) ,Human Geography ,Ecosystems ,Forest ecology ,Humans ,Human Development Index ,Ecosystem ,1172 Environmental sciences ,0105 earth and related environmental sciences ,Land use ,business.industry ,Global warming ,Ecology and Environmental Sciences ,AREA ,lcsh:R ,Biology and Life Sciences ,15. Life on land ,TRADE ,13. Climate action ,Earth Sciences ,BIODIVERSITY ,lcsh:Q ,DEFORESTATION ,business - Abstract
A universal turnaround has been detected in many countries of the World from shrinking to expanding forests. The forest area of western Europe expanded already in the 19th century. Such early trends of forest resources cannot be associated with the rapid rise of atmospheric carbon dioxide nor with the anthropogenic climate change, which have taken place since the mid 20th century. Modern, most recent spatial patterns of forest expansions and contractions do not correlate with the geography of climate trends nor with dry versus moist areas. Instead, the forest resources trends of nations correlate positively with UNDP Human Development Index. This indicates that forest resources of nations have improved along with progress in human well-being. Highly developed countries apply modern agricultural methods on good farmlands and abandon marginal lands, which become available for forest expansion. Developed countries invest in sustainable programs of forest management and nature protection. Our findings are significant for predicting the future of the terrestrial carbon sink. They suggest that the large sink of carbon recently observed in forests of the World will persist, if the well-being of people continues to improve. However, despite the positive trends in domestic forests, developed nations increasingly outsource their biomass needs abroad through international trade, and all nations rely on unsustainable energy use and wasteful patterns of material consumption.
- Published
- 2018
43. From divide to nexus : Interconnected land use and water governance changes shaping risks related to water
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Aleksi Räsänen, Anja Nygren, Adrián Monge Monge, Mira Käkönen, Sirkku Juhola, Markku Kanninen, Urban Environmental Policy, Environmental Sciences, Department of Political and Economic Studies (2010-2017), Global Development Studies, Department of Forest Sciences, Helsinki Institute of Sustainability Science (HELSUS), Viikki Tropical Resources Institute (VITRI), Forest Ecology and Management, and Teachers' Academy
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Risk ,IMPACTS ,010504 meteorology & atmospheric sciences ,Geography, Planning and Development ,Vulnerability ,Land cover ,010501 environmental sciences ,01 natural sciences ,SUSTAINABILITY ,MANAGEMENT ,FLOOD ,YANGTZE-RIVER ,Environmental planning ,ta218 ,0105 earth and related environmental sciences ,General Environmental Science ,BASIN ,5203 Global Development Studies ,CLIMATE-CHANGE ,Land use ,CHALLENGES ,Corporate governance ,Stakeholder ,Satellite imagery ,Forestry ,15. Life on land ,6. Clean water ,Water management ,COVER CHANGE ,Geography ,13. Climate action ,USE INTENSITY ,Tourism, Leisure and Hospitality Management ,Sustainability ,Water quality ,Nexus (standard) ,Water use ,Water governance - Abstract
Land use changes have been recognized to have considerable impacts on water; and vice versa, changes in water use and governance may have implications on land use and governance. This study analyzes recent land use/land cover (LULC) changes, and how changes in land use and water governance are perceived to affect land use and water-related risks in three case-study areas exposed to frequent flooding and inadequate or deteriorating water quality. The areas studied included the Vantaa basin in Finland, a section of the Grijalva basin in Mexico, and the Lower Xe Bang Fai basin in Laos. We show how there are complex and context-specific interrelationships between land use, water governance, and water-related risks in each study area. In a remote sensing analysis of LULC changes during the past 30 years, we found that LULC changes have been the most dramatic in Xe Bang Fai, Laos in the form of expanding agriculture and built-up areas; however, there has also been an expansion of built-up areas in the two other sites. According to our stakeholder scenario workshop data, analysis of policy documents and field visits, the nexus between land, water and risks is recognized to some extent in each study area. There have been modest shifts toward more integrated land use and water governance in Vantaa and Grijalva, while the integrated governance seems to have been most absent in Xe Bang Fai. Tighter integration of land and water policies is needed in all the three cases to manage the land use changes in a way that their effects on water-related risks will be minimized.
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- 2018
44. LiDAR patch metrics for object-based clustering of forest types in a tropical rainforest
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Graham Usher, Cici Alexander, Matthew G. Nowak, Ross A. Hill, Gabriella Fredriksson, and Amanda H. Korstjens
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0106 biological sciences ,Canopy ,010504 meteorology & atmospheric sciences ,CONSERVATION ,Rainforest ,Management, Monitoring, Policy and Law ,010603 evolutionary biology ,01 natural sciences ,INDONESIA ,Altitude ,AMAZON ,MANAGEMENT ,Satellite imagery ,Computers in Earth Sciences ,LANDSAT TM DATA ,0105 earth and related environmental sciences ,Earth-Surface Processes ,Batang Toru ,Global and Planetary Change ,Biomass (ecology) ,Sumatra ,DEGRADATION ,Classification ,Habitat ,COVER CHANGE ,Lidar ,SATELLITE DATA ,Environmental science ,Physical geography ,VEGETATION ,ALS ,Tropical rainforest ,Canopy Height Model - Abstract
Tropical rainforests support a large proportion of the Earth's plant and animal species within a restricted global distribution, and play an important role in regulating the Earth's climate. However, the existing knowledge of forest types or habitats is relatively poor and there are large uncertainties in the quantification of carbon stock in these forests. Airborne Laser Scanning, using LiDAR, has advantages over other remote sensing techniques for describing the three-dimensional structure of forests. With respect to the habitat requirements of different species, forest structure can be defined by canopy height, canopy cover and vertical arrangement of biomass. In this study, forest patches were identified based on classification and hierarchical merging of a LiDAR-derived Canopy Height Model in a tropical rainforest in Sumatra, Indonesia. Attributes of the identified patches were used as inputs for k-medoids clustering. The clusters were then analysed by comparing them with identified forest types in the field. There was a significant association between the clusters and the forest types identified in the field, to which arang forests and mixed agro-forests contributed the most. The topographic attributes of the clusters were analysed to determine whether the structural classes, and potentially forest types, were related to topography. The tallest clusters occurred at significantly higher elevations (> 850 m) and steeper slopes (> 26 degrees) than the other clusters. These are likely to be remnants of undisturbed primary forests and are important for conservation and habitat studies and for carbon stock estimation. This study showed that LiDAR data can be used to map tropical forest types based on structure, but that structural similarities between patches of different floristic composition or human use histories can limit habitat separability as determined in the field.
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- 2018
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45. Robust monitoring of small-scale forest disturbances in a tropical montane forest using Landsat time series
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Ben DeVries, Lammert Kooistra, Jan Verbesselt, and Martin Herold
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Soil Science ,Normalized Difference Vegetation Index ,etm plus data ,Laboratory of Geo-information Science and Remote Sensing ,geostatistical approach ,Deforestation ,detecting trends ,deforestation ,Laboratorium voor Geo-informatiekunde en Remote Sensing ,Satellite imagery ,Computers in Earth Sciences ,Time series ,satellite data ,southwest ethiopia ,Remote sensing ,Tropics ,Geology ,central-africa ,PE&RC ,cover change ,Disturbance (ecology) ,afromontane forests ,Environmental science ,Scale (map) ,imagery ,Change detection - Abstract
Remote sensing data play an important role in the monitoring of forest changes. Methods are needed to provide objective estimates of forest loss to support monitoring efforts at various scales, and with increasing public availability of remote sensing data, accurate deforestation measurements at high temporal resolution are becoming more realistic. While several time series based methods have recently been described in the literature, there are few studies focusing on tropical forest areas, where low data availability and complex change processes present challenges to forest disturbance monitoring. Here, we present a robust data-driven method to track tropical deforestation and degradation based on Landsat time series data. Based on the previously reported Breaks For Additive Season and Trend Monitor (BFAST Monitor) method (Verbesselt etal., 2012), we show that BFAST Monitor, when applied to Landsat NDVI time series data using sequentially defined monitoring periods, can be used to track small-scale forest disturbances annually in an Afromontane forest system in southern Ethiopia. Using an ordinal logistic regression (OLR) approach, change magnitude, calculated based on differences between observed and expected values in a monitoring period, was found to be an essential predictor variable for disturbances. After applying a NDVI change magnitude threshold of − 0.065, overall accuracy was estimated to be 78%, and both producer's and user's accuracy of the disturbance class were estimated to be 73%. The method and results presented here are relevant to tropical countries engaged in REDD + for whom data availability and complex forest change dynamics limit the ability to reliably track forest disturbances over time.
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- 2015
- Full Text
- View/download PDF
46. A test of an optimal stomatal conductance scheme within the CABLE land surface model
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Jatin Kala, Remko A. Duursma, Ying-Ping Wang, Diego G. Miralles, M. G. De Kauwe, Belinda E. Medlyn, Gab Abramowitz, Andrew J. Pitman, Yan-Shih Lin, Earth and Climate, and Amsterdam Global Change Institute
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0106 biological sciences ,Stomatal conductance ,010504 meteorology & atmospheric sciences ,Vapour Pressure Deficit ,Atmospheric sciences ,01 natural sciences ,Atmosphere ,CARBON-DIOXIDE ,LEAF ,GLOBAL CLIMATE MODEL ,Water-use efficiency ,AREA INDEX ,0105 earth and related environmental sciences ,Transpiration ,Hydrology ,VAPOR-PRESSURE DEFICIT ,lcsh:QE1-996.5 ,TRANSPIRATION ,Biosphere ,PLANT-ATMOSPHERE CONTINUUM ,Vegetation ,15. Life on land ,Plant functional type ,lcsh:Geology ,COVER CHANGE ,Earth and Environmental Sciences ,Environmental science ,SDG 6 - Clean Water and Sanitation ,WATER-USE EFFICIENCY ,GAS-EXCHANGE ,010606 plant biology & botany - Abstract
Stomatal conductance (gs) affects the fluxes of carbon, energy and water between the vegetated land surface and the atmosphere. We test an implementation of an optimal stomatal conductance model within the Community Atmosphere Biosphere Land Exchange (CABLE) land surface model (LSM). In common with many LSMs, CABLE does not differentiate between gs model parameters in relation to plant functional type (PFT), but instead only in relation to photosynthetic pathway. We constrained the key model parameter "g1", which represents plant water use strategy, by PFT, based on a global synthesis of stomatal behaviour. As proof of concept, we also demonstrate that the g1 parameter can be estimated using two long-term average (1960–1990) bioclimatic variables: (i) temperature and (ii) an indirect estimate of annual plant water availability. The new stomatal model, in conjunction with PFT parameterisations, resulted in a large reduction in annual fluxes of transpiration (~ 30% compared to the standard CABLE simulations) across evergreen needleleaf, tundra and C4 grass regions. Differences in other regions of the globe were typically small. Model performance against upscaled data products was not degraded, but did not noticeably reduce existing model–data biases. We identified assumptions relating to the coupling of the vegetation to the atmosphere and the parameterisation of the minimum stomatal conductance as areas requiring further investigation in both CABLE and potentially other LSMs. We conclude that optimisation theory can yield a simple and tractable approach to predicting stomatal conductance in LSMs.
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- 2015
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47. Land-based adaptation to global change: what drives soil and water conservation in Western Africa?
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H. Van Dijk and Diana Sietz
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Geography, Planning and Development ,factors influencing adoption ,Vulnerability ,Management, Monitoring, Policy and Law ,Forest and Nature Conservation Policy ,Order (exchange) ,southern mali ,Bos- en Natuurbeleid ,farmers perceptions ,Land based ,Dryland farming ,Adaptation (computer science) ,burkina-faso ,agricultural innovations ,Global and Planetary Change ,WIMEK ,Ecology ,business.industry ,Environmental resource management ,Global change ,Bodemfysica en Landbeheer ,northeast brazil ,dryland development ,central plateau ,cover change ,Soil Physics and Land Management ,Agriculture ,sub-saharan africa ,Business ,Soil conservation - Abstract
Conservation of land resources is a promising strategy for sustainable agricultural intensification in order to adapt dryland farming systems to climate, market and other stresses. At a local level, factors that drive the adoption of conservation measures operate and interact in specific ways. Linking our knowledge of the local specifications of these drivers to regional and global patterns of vulnerability can significantly enhance our understanding of land-based adaptation to global change. However, the factors that influence the adoption of conservation practices remain actively debated. Therefore, this study presents a meta-analysis of case studies that investigate the adoption of soil and water conservation measures, as an important approach to resource conservation. Synthesising 63 adoption cases in the drylands of western Africa, this meta-analysis reveals a multitude of factors that drive the adoption of soil and water conservation practices. The drivers differ strongly between particular practices and methods of analysis used in the case studies. Contributing to the broader debate on resource conservation, the findings highlight the adoption of soil and water conservation measures as an emergent property of farming systems. They demonstrate the need to better understand the socio-ecological foundation of adoption and the pathways along which adoption evolves in space and time. This study concludes with methodological principles to advance future research on the factors that drive the adoption of soil and water conservation measures as a pre-requisite of improving land-based adaptation efforts.
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- 2015
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48. Free and open-access satellite data are key to biodiversity conservation
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Peter Leimgruber, John L. Dwyer, Carlo Rondinini, Zoltan Szantoi, Brice Mora, Curtis E. Woodcock, Hannes Taubenboeck, Woody Turner, Martin Wikelski, Nathalie Pettorelli, Lian Pin Koh, Martin Herold, Graeme M. Buchanan, Allison K. Leidner, Stefan Dech, and Martin Wegmann
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0106 biological sciences ,010504 meteorology & atmospheric sciences ,landsat ,Computer science ,satellite ,remote sensing ,biodiversity ,conservation ,monitoring ,Satellite, Remote sensing, Biodiversity, Conservation, Monitoring, Landsat ,Biodiversity ,challenges ,system ,Conservation communities ,010603 evolutionary biology ,01 natural sciences ,GeneralLiterature_MISCELLANEOUS ,opportunities ,Laboratory of Geo-information Science and Remote Sensing ,ddc:570 ,Measurement of biodiversity ,Satellite imagery ,Laboratorium voor Geo-informatiekunde en Remote Sensing ,14. Life underwater ,landsat imagery ,Ecology, Evolution, Behavior and Systematics ,science ,0105 earth and related environmental sciences ,Nature and Landscape Conservation ,Government ,support ,article lsfe conservation biodiversity ,business.industry ,Ecology ,Environmental resource management ,15. Life on land ,PE&RC ,cover change ,Open data ,Data access ,13. Climate action ,Remote sensing (archaeology) ,business - Abstract
Biodiversity underpins the health of ecosystems and the services they provide to society. Yet biodiversity is in rapid decline globally, despite commitments by world leaders to reduce the rate of loss (1). Monitoring is an essential part of biodiversity conservation, allowing governments and civil society to identify problems, develop solutions, and assess progress (2). Satellite imagery has emerged as a vital tool for monitoring the status of environmental parameters relevant to biodiversity conservation (3-5). Tackling a global challenge like biodiversity loss requires the assembly of global information products. Satellite remote sensing is especially useful at generating consistent observation records of key drivers of biodiversity change (i.e., land cover and land use dynamics, climate variables, and sea surface conditions) at a global level (6-8). A recent review of the needs of the biodiversity research and conservation communities for satellite remote sensing (9) uncovered three factors, which are rooted in government and commercial policies and actions, that ultimately have a disproportionate impact on the utility of satellite data for understanding changes in biodiversity. These factors are data continuity, data affordability, and data access., JRC.H.5-Land Resources Management
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- 2015
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49. From global economic modelling to household level analyses of food security and sustainability: How big is the gap and can we bridge it?
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Mark T. van Wijk
- Subjects
Economics and Econometrics ,Sociology and Political Science ,Distribution (economics) ,challenges ,Mosaic (geodemography) ,Management, Monitoring, Policy and Law ,Development ,agricultural land-use ,Agricultural land ,production systems ,Economics ,integrated assessment ,Production (economics) ,farming systems ,science ,Food security ,Impact assessment ,business.industry ,Environmental resource management ,earth system ,Environmental economics ,PE&RC ,cover change ,Earth system science ,Plant Production Systems ,Plantaardige Productiesystemen ,climate-change ,Sustainability ,business ,east-africa ,Food Science - Abstract
Policy and decision makers have to make difficult choices to improve the food security of local people against the background of drastic global and local changes. Ex-ante impact assessment using integrated models can help them with these decisions. This review analyses the state of affairs of the multi-scale modelling of policy interventions, with an emphasis on applications in developing countries and livestock systems. Existing models do not sufficiently capture the complexity of human-environment interactions across different scales, and especially the link between landscape and local market levels, and national and sub-national level policies and markets is missing. The paper suggests a step wise approach with increasing data needs to bridge this gap. Improvements need to be made at the description of effects of the distribution of local markets on price formation and the representation of farm diversity within a landscape. Analyses in contrasting agro-ecological systems are needed to derive generic summary functions that can be used as input for macro level model analyses. This is especially pertinent for macro level descriptions of crop and livestock production in relation to price developments and of the mosaic of different agricultural land use responses in regions with contrasting socio-economic conditions and developments.
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- 2014
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50. Simulating the impacts of future land use change on soil erosion in the Kasilian watershed, Iran
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Mohammad Zare, Thomas Panagopoulos, and Luís Loures
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China ,Sediment Yield ,010504 meteorology & atmospheric sciences ,Climate ,Geography, Planning and Development ,Climate change ,Soil science ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,01 natural sciences ,11. Sustainability ,Land use, land-use change and forestry ,Baseline (configuration management) ,skin and connective tissue diseases ,0105 earth and related environmental sciences ,Nature and Landscape Conservation ,Cover Change ,Land use ,business.industry ,Rusle ,Forestry ,15. Life on land ,Gis ,Scale ,Watershed management ,Cellular-Automata Models ,Loess Plateau ,13. Climate action ,Land degradation ,Erosion ,Environmental science ,Loss Equation ,Land development ,sense organs ,Water resource management ,business - Abstract
Predicting soil erosion potential is important in watershed management. A rapidly growing Iranian population and climate change are expected to influence land use and soil sustainability. in recent years, northern Iran has experienced significant land use changes due to internal migration along the Caspian coast and conversion of forests and rangelands. Considering the effect of these changes in the future, the purpose of this study is to forecast land use patterns and investigate soil erosion scenarios using the Revised Universal Loss Equation and Markov Cellular Automata. Data from 1981 to 2011 were used as a baseline to estimate changes that might occur in 2030. The results reveal that the mean erosion potential will increase 45% from the estimated 104.52 t ha(-1) year(-1) in the baseline period. Moreover, the results indicate that land use change from forest area to settlements will be the most significant factor in erosion induced by land use change, showing the highest correlation among erosional factors. Projecting land use change and its effect on soil erosion indicate that conversion may be unsustainable if change occurs on land that is not suited to the use. The method predicts soil erosion under different scenarios and provides policymakers a basis for altering programs related to land use optimization and urban growth. Those results indicated the necessity of appropriate policies and regulations particularly for limiting land use changes and urban sprawl in areas of unfavorable soil erosion risk factors. Research Center for Spatial and Organizational Dynamics (CIEO) Portuguese Foundation for Science (FCT)
- Published
- 2017
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