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Abstract Land use and land cover (LULC) changes in oases have been a topic of great interest due to the impacts of oases on ecosystem services in arid regions. The oasis that is along the Keriya River in southern Tarim Basin, northwest China, is in an ecologically fragile region and is thus very sensitive to human interference. In this study, the spatial and temporal changes in LULC in the middle reaches of the river were quantified and assessed by using GIS technology based on remote sensing images from 1995, 2005 and 2015. The results indicated that cropland expansion and grassland degradation were the dominant LULC changes, especially in the last decade. Throughout the study period, cropland areas increased by 6.51%, while grassland areas decreased by 30.98%. A buffer analysis along the main river channel was conducted to analyze the spatial LULC characteristics. The results showed that water areas, croplands and forests were predominantly distributed along the river (in the 0–10 km buffer). The majority of mid-density grasslands and low-density grasslands were distributed in the 10–20 km buffer, and high-density grasslands were mainly distributed in the 20–30 km buffer. The conversion rates in different buffers indicated that cropland expansion primarily occurred along the river, and grassland degradation was noted in the 10–30 km buffer. Landscape pattern changes were also analyzed to account for the structural LULC characteristics. The results that were deduced from the landscape pattern change analysis showed that the patch structures of forestland and cropland increased, and increasing fragmentation tendencies were found in the other LULC types. Moreover, a model was introduced to quantify the directions of LULC changes, and the results showed that the direction of LULC change in the oasis was declining, which represents an undesirable change in LULC. Socio-economic changes were also analyzed to explain the LULC changes. The results of this study contribute to the future management of the LULC in the oasis and the protection of the Keriya River ecosystem. Highlights • Cropland expansion and grassland degradation were the dominant changes. • Changes were spatially arranged along the distance from the river channel. • Cropland expansion was intensive along the river. • Grassland degradation primarily occurred at oasis-desert ecotone. • The comprehensive ecosystem function had declined from 1995 to 2015. [ABSTRACT FROM AUTHOR]

The Transition towards sustainable energy systems requires phasing out fossil fuels. Hydropower is a key source of renewable energy and can contribute to reaching a 100 % low carbon-based energy system. Uncertainty remains about land cover changes due to hydropower deployment with a widespread perception of major losses in the land from inundation and associated habitat loss in the surrounding areas due to improved access and recreational use. Norway has a dominant share of hydropower generation in Europe with knowledge gaps in the associated land cover changes. We conducted one of the first retrospective analyses of land use change associated with hydropower development in Norway during the last 80 years. Using remote sensing data, we performed object-based analysis on sets of aerial images representing land systems before and after hydropower construction. We quantified the change in the land due to development of 40 hydropower schemes representing 24 % of the total Norwegian installed capacity. Our analysis revealed that 88 % of analyzed reservoirs were developed by regulating or expanding natural lakes. Vegetation growth was observed in the surrounding regions of 22 of 40 schemes, while urbanization was limited to only 0.9 % of the total surrounding area, primarily located within 400 m from reservoir's borders. Our findings provide insights into interaction between land use change and hydropower development in Norway. Our work provides a basis for further assessment of relevant environmental impacts and can be used to quantify expected land changes due to an increase in Norway's hydropower with integration into the European energy market. [Display omitted] • A Majority of the hydropower projects were in isolated mountain areas. • Most Norwegian reservoirs were developed on natural lakes. • Induced urbanization was limited to an average of 0.9 % of the surrounding land. • Influence distance was up to 400 m from reservoirs and 150 m from brook dams. • Hydropower projects have had vegetation regrowth since construction. [ABSTRACT FROM AUTHOR]

Pirate attacks are among the most important factors affecting maritime safety in recent years. In this study, big data were analyzed to extract the patterns and characteristics of piracy incidents and to reveal risk control options and recommendations for anti-piracy measures. Global and regional spatial patterns and characteristics were identified with the support of a geographic information system. In total, 3675 maritime piracy incidents from 2010 to 2022 were collected from the Piracy and Armed Robbery module of the Global Integrated Shipping Information System to profile the characteristics of global piracy. To visualize and analyze the features of maritime piracy, we used three geospatial techniques: kernel density estimation (KDE), k -means clustering, and buffer analysis. These geospatial techniques were used to create a KDE map for identifying piracy-prone areas. We subdivided the incidents into several classes and analyzed the features within each class to calculate the incidents that occurred in coastal areas. The following results were obtained from the geospatial analysis. First, the results of the KDE method revealed specific regions that were particularly prone to piracy, namely the Gulf of Guinea in West Africa; the seas around East Africa and the Arabian Sea; the Malacca Strait and parts of Southeast Asia and the Bay of Bengal; and the seas around South America. Second, the distributions of maritime piracy incidents by different temporal criteria, location, and ship type were compared within different classes. In particular, we found that 79.97% of minor incidents, 43.4% of less serious incidents, 50% of serious incidents, and 30.9% of very serious incidents occurred within 40 km of the coastline. The results obtained from the study contributed to an understanding of the spatial patterns of maritime piracy and provided information useful to maritime safety organizations for enhancing shipping safety. • Piracy-prone areas were identified with the support of kernel density estimation. • The geographical characteristics of maritime piracy were analyzed based on 3675 maritime piracy incidents from 2010 to 2022. • The proportion of maritime piracy incidents within different boundaries was calculated using buffer analysis. [ABSTRACT FROM AUTHOR]

The route planning before tourists going to an unfamiliar city is relatively subjective, which can hardly provide maximum motive benefits. Aimed at the problem, tourism route decision support based on neural net buffer analysis model is brought up in this paper. Firstly, sight spots in Zhengzhou city are taken as examples to ensure research objects. GIS buffer analysis and manual neural net are taken as basic model to ensure research method, on which base, motive iterative function transmission model related to neural net transmission chain and service facility in sight spots buffer is set up. And then three downtown sight spots are taken as algorithm example to research the feasibility of the model to calculate motive iterative function output value of different tourism routes with the same sight spots, which provides objective tourism route decision support for tourists. Algorithm example proves that the model brought up in this paper is feasible and valuable, and can provide effective decision support for tourists. [ABSTRACT FROM AUTHOR]

Buffer zones in bo\th two-dimensional (2D) and three-dimensional (3D) spaces are commonly used in prospectivity mapping. The method completes a modelling that starts with a real example and progresses to the development of a virtual model. This includes the consideration of lithological or structural contacts at depth, which is a theoretical concept based on extrapolation of data collected in the field, rather than an empirical observation of the feature based on physical samples. This contribution documents an improved buffer analysis method for the study of 3D-space that is implicit (rapid), precise (smooth) and based on triangulated characteristics, which can be used to construct influence domains of geological models. As traditional 2D GIS-based mineral potential mapping is gradually becoming limited with time, mineral potential mapping in three dimensions (3D) is increasingly becoming an important tool in finding concealed economic mineralization. This contribution documents an improved methodology of buffer analysis for prospectivity mapping processing mineralized favourable models rather than describing an advance in the geometry of surface rendering of “geological complexity”. Measures used in this buffer analysis include the: (1) voxelization of geological objects (i.e. assigning numerical values of features on a regular cube in 3D-space); (2) revision of the 3D Euclidean distance transform and the calculation of signed distance field; (3) extracting surfaces from the field; and (4) construction of a buffer-surface based on a “discrete smooth interpolation” (DSI) algorithm. Furthermore, this contribution constructs 3D models using a buffer analysis algorithm and prospectivity mapping introduced here, which is based on real data from the Jiama Cu-polymetallic deposit in Tibet and Daye Fe deposit in the Hubei Province, China. This contribution also presents a comparison between voxel and irregular triangle models, which illustrate that irregular triangle mesh buffer analysis (ITB) can improve modelling techniques for GIS-based 3D mineral potential mapping. The outcome is an increase in the accuracy of prospectivity mapping. [ABSTRACT FROM AUTHOR]

Pipeline construction has severe disturbance on local ecosystems, especially in arid and semi-arid regions. Vegetation recovery along the pipeline is crucial for ecosystem management and eco-environment restoration. In this study, three typical regions with different backgrounds and engineering characteristics in northwest China were selected to analyze vegetation recovery pattern after pipeline disturbance by using comparative analysis and RDA analysis. The results showed that vegetation condition in the zone 10 m from the pipeline was worse than construction area above the pipeline, and was identified as a key area in which vegetation restoration needs to occur. Rainfall and total sunshine duration were found to be key factors affecting vegetation recovery. Additionally, recovery duration also played important roles in vegetation recovery. The affecting factors can be divided into two categories: environmental factors; and, engineering factors. Environmental factors contribute more to the differences of vegetation in different regions, while the engineering factors may play a more important role in relation to vegetation recovery within a region. In general, the effects of pipeline construction on vegetation pattern were confined to 300 m from the pipeline based on this study. However, artificial measures may hasten the vegetation recovery process. This research could provide scientific guidance for ecological restoration and environmental management for the construction of linear projects. [ABSTRACT FROM AUTHOR]

Negative air ions play an important role in absorbing dust, cleaning the air, and improving both the environment and human health. Based on data collected from the suburb of Maiji in 2013, using methods such as partial correlation analysis, semi-variation analysis, Kriging interpolation, re-classification and buffer analysis, this study analyzes the ecological effects of negative air ions in vegetated areas of the Maiji district. The results were as follows: (1) the concentration of negative air ions was negatively correlated with temperature, NO x , SO 2 and aerosols, which had an influence on them; (2) the ratio of partial sill to sill was 83.7% and the ratio of nugget to sill was 16.25%; the negative air ions demonstrated a significant spatial autocorrelation, with an effect range of 262.929 m; (3) the concentration of negative air ions in two-thirds of the study area was more than 1500 unit cm −3 and the average concentration was 2514 unit cm −3 , which suggests good air quality; (4) the concentration of negative air ions was different among various types of vegetation; the average concentration was 3759 unit cm −3 in natural forests and their surroundings, with a maximum value of up to 5000 unit cm −3 ; the average concentration was 1984 unit cm −3 in economic forests, 1811 unit cm −3 in greenbelt, and 1634 unit cm −3 in farmlands. The effect of negative air ions in the Maiji district was outstanding at absorbing dust and cleaning the air, and was closely related to the vegetation structure, temperature, NO x , SO 2 , aerosols and altitude. These results can provide a theoretical foundation and technical guidance for planning and constructing an urban vegetated area in the Maiji district, which will improve the environmental quality of the city. [ABSTRACT FROM AUTHOR]

Traffic-related air pollution (TRAP) likely exerts a large burden of disease globally, and in many places, traffic is increasing dramatically. The impact, however, of urban form on the portion of population potentially exposed to TRAP remains poorly understood. In this study, we estimate portions of population potentially exposed to TRAP across seven global cities of various urban forms. Data on population distributions and road networks were collected from the best available sources in each city and from remote sensing analysis. Using spatial mapping techniques, we first overlaid road buffers onto population data to estimate the portions of population potentially exposed for four plausible impact zones. Based on a most likely scenario with impacts from highways up to 300 meters and major roadways up to 50 meters, we identified that the portions of population potentially exposed for the seven cities ranged from 23 to 96%. High-income North American cities had the lowest potential exposure portions, while those in Europe had the highest. Second, we adjusted exposure zone concentration levels based on a literature suggested multiplier for each city using corresponding background concentrations. Though Beijing and Mexico City did not have the highest portion of population exposure, those in their exposure zones had the highest levels of exposure. For all seven cities, the portion of population potentially exposed was positively correlated with roadway density and, to a lesser extent, with population density. These analyses suggest that urban form may influence the portion of population exposed to TRAP and vehicle emissions and other factors may influence the exposure levels. Greater understanding of urban form and other factors influencing potential exposure to TRAP may help inform interventions that protect public health. [ABSTRACT FROM AUTHOR]

Abstract: Based on Landsat MSS and TM images from 1974, 1988, and 2004, we conducted a case study of the Manwan Dam along the Lancang (Mekong) River to determine the influencing distance of dam construction and reservoir impoundment on land use. Spatio-temporal variation in land use was analyzed within 14 adjacent buffer zones around the dam site (concentric rings) and in upstream and downstream areas along the riverway (linear tract). Grassland increased with the greatest dynamic degree in the 1974–1988 period, whereas water area increased extensively in the 1988–2004 period. The integrated dynamic degrees of forestland were low in both periods. The integrated land use dynamics in the 14 concentric rings showed that the impact of dam construction extended to a threshold distance of 5000–6000m from the dam site during the 1974–1988 period and to 2000–3000m during the 1988–2004 period. The transformational patch density in the 14 linear buffer zones indicated that the impact of reservoir impoundment on land use conversion exhibited a threshold distance of 3000m from the riverway. The impact intensity of dam construction in the concentric rings and linear buffer zones tended to decline with increasing distance from the dam site or riverway. The impacts of dam construction and reservoir impoundment were larger in upstream locations than in downstream ones. Our results enhance our understanding of the threshold of dam construction and may guide the management of dam construction on a regional landscape level. [Copyright &y& Elsevier]

Abstract: A GIS-based gradient analysis is a useful tool for exploring spatiotemporal dynamics of urban land-use. Although some case studies have been conducted confirming the efficacy of this approach, the gradient analysis of large-scale regional urbanization has still been seldom documented, and the urbanization of satellite cities and their interactions with a central city in regional urbanization have also been poorly explored. In this study, a combination of remotely sensed data, urbanization metrics and GISbased buffer gradient analysis is employed to analyze the overall spatiotemporal characteristics of urban expansion in the Shanghai region, China, and to explore the urbanization of its major satellite cities and their interactions. The results show the overall spatiotemporal changes in the urbanization gradient are largely influenced by the distance from the urban center, yet there are distinct spatial variations mainly resulting from the interactions of the urbanization of the central city with that of satellite cities. The urbanization within the urban-suburb transitional zones generally had a specific rhythm of intensity and weakness, which can function as the spatial signatures to analyze and demonstrate similar or other types of urbanization processes. The major satellite cities of the Shanghai region showed their distinct temporal-spatial characteristics in their urban expansion behaviors, and thus can be categorized as autonomous, passive, steady and irregular modes of urbanization. [ABSTRACT FROM AUTHOR]

• Ecological security patterns was optimized considering social equity. • 19 ecological sources and 51 corridors were identified by ESA-MCR Model. • 1 amendment source and 25 amendment corridors were proposed by buffer analysis. • Four types of ecological zones were proposed and joint management strategies were formulated. Ecological Security Patterns (ESPs) are important nature-based solutions for ecological problems caused by urbanization and industrialization. Previous studies on ESPs focus on natural conditions only, yet do not incorporate the need for social equity. This study aims to address this quandary for the study area of Wuhan by identifying and extracting ecological sources and ecological corridors, followed by an ecological sensitivity assessment, minimum cumulative resistance model and buffer analysis, in order to construct and optimize ecological security patterns. The optimization for the construction of the most suitable ecological security patterns relies on social equity aspects, including the quality of urban ecological services and the improvement of the well-being of urban residents. The results demonstrate: (1) There are 19 ecological sources in Wuhan and 51 ecological corridors with a total length of 840.10 km. (2) To cater for the optimization of social equity needs, it was necessary to add one additional amendment source, with an area of 14.89 km2, and 25 new amendment corridors with a total length of 287.8 km. (3) Optimizing the ecological security patterns in Wuhan is possible through the derivation of an ecological restoration area, ecological improvement area, ecological control area and ecological shield area. The results indicate the feasibility of simultaneously protecting urban ecological security and realizing social equity. [ABSTRACT FROM AUTHOR]

• The intra-region air pollutant variations are even greater than inter-region/season differences. • Cropland is more important in causing air pollution at regional scales, while the impervious surface mainly impacts at local scales. • Cropland acts as the source of NO 2 in the north and sink of NO 2 in the south. • The relationship between extreme O 3 levels and LC shows increased variations across seasons from south to north. China's urbanization process is accompanied by land use and cover change (LUCC), influencing variations of air pollutants at multiple spatial scales. Monitoring the spatiotemporal variations of air pollutants and their relationship with land cover (LC) is vital for understanding the mechanisms of land-air interaction and guiding environmental management. In this study, both statistical and geo-statistical analysis is used to investigate the relationship between spatiotemporal variations of air pollutants and LC composition in the vicinity of China's three major urban agglomerations (UAs), including Jing-Jin-Ji (JJJ), Yangtze River Delta Region (YRD), and Guangdong-Hong Kong-Macau Greater Bay Area (GBA). Results show that the spatial variations of six criteria air pollutants intra-region are large, even greater than inter-region and inter-season differences. Partial correlation analysis shows that although the impervious surface is the main driving force in elevating air pollution on a local scale, cropland is more important in elevating air pollutant levels at a regional scale. Besides that, the relationship between air pollutant levels and LC demonstrates varied seasonal and regional characteristics for different air pollutants. Our analysis provides a comprehensive understanding of the relationship between air pollutant levels and LC composition, emphasizing the impact of LC at different spatial scales. [ABSTRACT FROM AUTHOR]

Land use changes in the tropics under the pressure of population growth have attracted wide attention. In this study, the riparian area with more settlements was selected to explore the land use temporal-spatial characteristics of the less developed Lake Tanganyika region. The study methods employed mainly included land use transition matrix, kernel density estimation, grid and buffer analysis of the ArcGIS software and remote sensing image processing. The changes of land use mainly reflected in the transformation between different land types, among which the conversion from forestland into arable land constituted the major event. Though the land use change rate was not so significant for the whole region, dramatic changes occurred around the towns especially in the northern area. It was found that a circle of arable land of about 6 km in width and more than 40% arable land density composed the farming hinterland of the major towns. Moreover, with the forest transition theory the change trends of land use and their influencing factors were analysed. The findings in this study should be helpful for the land use simulation and planning in similar riparian areas. For better understanding the dynamic of land use change, a future additional in-depth study at extensive spatial and temporal scale is appealed. • The land use changes in the riparian area of Lake Tanganyika were investigated. • Data within 10 km around the lake from 2001 to 2011 were analysed. • The conversion of forestland into arable land was the highest. • The arable land and forestland changes fluctuated with the distance from settlements. • The findings may facilitate land use simulation and planning in riparian areas. [ABSTRACT FROM AUTHOR]

• Increasing population and urbanization altered land use patterns in central Taiwan. • Urbanization in Taiwan includes agricultural, industrial, and service economy periods. • A buffer analysis quantified the land use area around egret nesting sites. • The similarity between egret nesting sites and land use area change was investigated. • HCA and MDS could be used to initially identify an urbanization process. Population increase and urbanization have considerably altered land-use patterns in central Taiwan. To determine the effects of urbanization in central Taiwan, this study used a buffer analysis, hierarchical cluster analysis, and multidimensional scaling to identify the relationship between egret nesting sites and land-use changes during the agricultural, industrial, and service economy periods of the urbanization process. The results demonstrate that built-up land increased markedly over time in central Taiwan, especially within the 1-km circle buffer of egret nesting sites. A longer interquartile range in the service economy period indicates that the distribution of cultivated land near egret nesting sites was relatively fragmented. The types of land-use with similar features were clustered into the same group using hierarchical cluster analysis and multidimensional scaling. The group classification results of the hierarchical cluster analysis and multidimensional scaling were consistent with the results of the Pearson correlation analyses. The horizontal axis in the multidimensional scaling dendrogram may represent the gradient from the main to minor food source areas. Hierarchical cluster analysis and multidimensional scaling could be used for initial identification of urbanization processes. Furthermore, egrets in central Taiwan adapted to urbanization and fed on discarded human food during Taiwan's service economy period. [ABSTRACT FROM AUTHOR]