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Globally, animals that are range-restricted are frequently becoming species of conservation concern, in part due to competitive exclusion by phylogenetically and ecologically similar species that are more tolerant of human disturbance. However, climate and land use changes to natural landscapes can create pockets of refugia for range-restricted species. Western gray squirrels (Sciurus griseus) are native to the west coast of North America, principally California and western Oregon. Over the past several decades, Western Gray Squirrel populations have declined in human-dominated areas, with increased competition from introduced congeneric species native to eastern North America cited as a primary driver. Despite declines in their established range west of the Pacific Crest in western North America, western gray squirrels are extending their range into the Great Basin, where they were not historically found. Using a network of remote camera traps deployed across the Sierra Nevada–Great Basin ecotone in northwestern Nevada, we detected western gray squirrels across 16 of 100 camera-trapping sites. The majority of detections were located in piñon–juniper woodland, a land cover type not previously occupied by this species. Occupancy modeling revealed that western gray squirrels were equally likely to occur in piñon–juniper woodland compared to mature pine forest that they occupy elsewhere in their range. A species distribution model parameterized with historical gray squirrel observations (pre-1950), indicated increased climatic suitability for the species on the eastern side of the Sierra Nevada in recent decades, which may have facilitated this range expansion. Our findings reveal the potential for species declining in their historical range to colonize novel habitats that become increasingly suitable as a result of human-driven changes to ecosystems. [ABSTRACT FROM AUTHOR]

Soil erosion poses an environmental threat to the ecosystem functions. Land use and land cover (LULC) changes are largely responsible for soil erosion severity. This study aimed to evaluate the impacts of LULC on soil erosion and erosion distribution in the Laonung watershed over the study period (1995–2016). To model the response of soil erosion to LULC changes, a physiographic soil erosion–deposition (PSED) model is employed, which incorporates Geographic Information Systems (GIS) with rain-runoff models and erosion–deposition models. The results revealed that over a three period (1995, 2008 and 2011), agricultural land, grassland, bare land, water bodies, and other land uses increased, whereas forest land declined by 11,424 × 104 m2 (2008 relative to 1995) and 16,159 × 104 m2 (2011 relative to 1995). In addition to the land use, landslide was considered as a land cover in this study. As landslides dramatically alter the land cover dynamics of mountainous regions in Taiwan. The landslide areas substantial changed over the period 2003 to 2016 (847 × 104 m2–9474 × 104 m2). The significant increase in landslide area together with the abrupt dynamics in LU severely aggravated soil erosion. Compared with the period of primeval forest, total soil erosion increased from 29,295 × 104 m3 to 102,597 × 104 m3 (1995–2011 LU) and 205,833 × 104 m3 (LULC). The study has illustrated how LULC changes strongly affects soil erosion. [ABSTRACT FROM AUTHOR]

The systematic decline of land quality due to the mismatch between land quality and land use is called land degradation. It is the consequences of different physical factors but accelerated by human activities. The processes and factors of land degradation are different in different morpho-climatic regions of the world. Present study is primarily concerned in identifying the factors and status of land degradation in a tropical plateau region. Tropical plateaus are one of the most water erosion related land degraded areas of world. Chotanagpur plateau in tropical eastern India is one of the vulnerable soil degraded areas of the tropical environment. The Precambrian geological formation, undulating topography, immature soil, increasing aridity sets natural settings for land degradation in tropical plateau areas. However, induced degradation results from inappropriate land use, clearance of forest land and heavy land pressure related anthropogenic factors accelerates the processes of land degradation. Kangsabati River basin of eastern Chotanagpur plateau bears all of the above characteristics has been taken for present study as a degraded tropical plateau region. Water erosion and vegetal degradation are the major factors of land degradation in Kangsabati basin. The physical factors responsible for land degradation in the studied area includes physiographic formations, edaphic maturity, hydrologic characteristics, and vegetation cover dynamics etc. This land degradation processes is accelerated by different anthropogenic factors like, land use land cover dynamics, deforestation, agricultural pressure. Multispectral remote sensing data, digital elevation data, thematic maps, recorded climatological data, secondary data and field observation have been utilised to understand the different factors of land degradation in a typical tropical plateau region. The less developed soil profile over Precambrian geology with undulated landforms causes high soil erosion in upper plateau proper regions of the basin. High agricultural pressure, forest and groundwater decline with associated land use land cover dynamics creates decline of land quality in lower basin regions of tropical plateau. The varying intensities of land degraded areas for the basin has been identified through the multiplication of different physical and anthropogenic factor overlaying rasters in GIS environment. Before multiplying, each of these input factor rasters has assigned with weightage after considerable importance of land degradation. The lower basin area with accelerated human interference is the most vulnerable land degraded area for the Kangsabati River basin. [ABSTRACT FROM AUTHOR]

• Land cover dynamics in dry tropical environments are often overlooked. • Classification accuracy of 79–86% was attained using Landsat data. • Primary forest declined, while secondary forest increased. • Deforestation has continued to increase with low rates of recovery. • Forest connectivity declined by 22% between 1972 and 2016. Land cover dynamics in the tropical dry environments of sub-Saharan Africa are not well understood compared to humid environments, especially on a national scale. Previous studies describing land cover in the dry tropics are spatially or temporally constrained. This study presents the first long-term (1972–2016) nationwide land cover dynamics and forest connectivity analyses for Zambia. We employed 300 Landsat images and an object-based image analysis (OBIA) approach with the Random Forests (RF) classifier to map nine land covers at six time steps (1972, 1984, 1990, 2000, 2008 and 2016). Post-classification change detection was used to understand the dynamics, while landscape metrics were derived to assess the forest structural connectivity. Overall accuracies ranging from 79 to 86% were achieved. In 1972, 48% of Zambia was covered by primary forest and 16% was covered by secondary forest. By 2016, 62.74% of Zambia had undergone changes, with primary forest decreasing by 32% and secondary forest increasing by 23%. Our results showed that forests have been recovering by 0.03 to 1.3% yr−1 (53, 000–242, 000 ha yr-1); however, these rates are markedly lower than deforestation rates (- 0.54 to - 3.05% yr-1: 83, 000–453, 000 ha yr-1). Annual rates of change varied by land cover, with irrigated crops having the largest increase (+ 3.19 yr-1) and primary forest having the greatest decrease (-2.48% yr-1). Forest connectivity declined by 22%, with primary forest having the greatest decline, while the connectivity for secondary and plantation forest increased. We showed here that land cover in Zambia is highly dynamic with high rates of change, low forest recovery and decline in forest connectivity. These findings will aid in land use planning, reporting for the forthcoming 2020 Global Forest Resources Assessment, and carbon accounting, especially under the reduction in carbon emissions from deforestation and degradation programme (REDD+). [ABSTRACT FROM AUTHOR]

• The result of the study indicated that significant LULC changes have happened over the past 46 years. • The study revealed that forest land has declined from 20.9 % in 1973 to 13.7 % in 2019. • The study also revealed the decline of wetlands from 24.0 % in 1973 to 4.8 % in 2019. • LULC dynamics in the study area is driven by a combination of proximate and underlying causes. • The results of the study revealed that there is a significant increase in agricultural land, during the study periods Information on Land Use and Land Cover (LULC) changes and the driving forces behind such modifications underpin a proper understanding of the dynamics of LULC changes. This study aimed to analyse the dynamics of LULC change trends and its driving factors in Jimma Geneti District (JGD) for the year 1973–2019. Five satellite images downloaded from USGS were used to analyze and assess the geospatial and temporal changes in LULC. In addition, in-depth household interviews, key informant interview, focus group discussions (FGD) and field observations were used to address the drivers of LULC changes. The result showed a decline in forest land from 8632.5 ha (20.9 %) in 1973–5647.23 ha (13.7 %) in 2019. The study further revealed that the total of forest land cleared between 1973 and 2019 was estimated to be 2985.27 ha (7.22 %). In other words, 34.6 % of the forest cover that existed in 1973 was lost. Similarly, wetlands declined from 9919.5 ha (24.0 %) in 1973–2000.24 ha (4.8 %) in 2019. Similarly, wetlands declined from 9919.5 ha (24.0 %) in 1973–2000.24 ha (4.8 %) in 2019. On the other hand, cultivated land has increased from 18617.0 ha (45.1 %) to 27708.1 ha (67.1 %). Similarly, the increment in settlement areas has elevated from 908.7 ha (2.2 %) to 4436.46 ha (10.7 %) during the same period. Agricultural expansion, cutting trees for various purposes (such as firewood, charcoal and construction material), overgrazing and the expansion of settlements, were identified as the major proximate causes of these changes. Moreover, the major underlying drivers of LULC changes include population growth, changes in policy and institutions, poverty and lack of awareness on the importance of natural resource conservation for sustainable livelihoods. From this study, it can be concluded that JGD has experienced a significant change in LULC over the past 46 years and were affected both positively and negatively. Hence, a wide range of policy packages are required for sustainable land management practices which take in to account synergies and trade-offs between the various land uses in the study area. The national and local governments should enforce sustainable land management approaches through integrating land use planning and management into all development programmes and projects. [ABSTRACT FROM AUTHOR]

The Zagros forests in Western Iran are valuable ecosystems that have been seriously damaged by human interference (harvesting the wood and forest sub-products, converting the forests to the agricultural lands, and grazing) and natural events (drought events and fire). In this study, we generated accurate land cover (LC), and tree canopy cover percentage (TCC%) maps for the forests of Shirvan County, a part of Zagros forests in Western Iran using Sentinel-2, Google Earth, and field data for protective management. First, we assessed the accuracy of Google Earth data using 300 random field plots in 10 different land cover types. For land cover mapping, we evaluated the performance of four supervised classification algorithms (minimum distance (MD), Mahalanobis distance (MaD), neural network (NN), and support vector machine (SVM)). The accuracy of the land cover maps was assessed using a set of 150 stratified random plots in Google Earth. We mapped the forest canopy cover by using the normalized difference vegetation index (NDVI) map, and field plots. We calculated the Pearson correlation between the NDVI values and the TCC% (obtained from field plots). The linear regression between the NDVI values and the TCC% was used to obtain the predictive model of TCC% based on the NDVI. The results showed that Google Earth data yielded an overall accuracy of 94.4%. The SVM algorithm had the highest accuracy for the classification of Sentinel-2 data with an overall accuracy of 81.33% and a kappa index of 0.76. The results of the forest canopy cover analysis showed a Pearson correlation coefficient of 0.93 between the NDVI and TCC%, which is highly significant. The results also showed that the linear regression model is a good predictive model for TCC% estimation based on the NDVI (r2 = 0.864). The results can be used as a baseline for decision-makers to monitor land cover change in the region, whether produced by human activities or natural events and to establish measures for protective management of forests. [ABSTRACT FROM AUTHOR]

Land cover changes, especially excessive economic forest plantations, have significantly threatened the ecological security of West Dongting Lake wetland in China. This work aimed to investigate the spatiotemporal dynamics of forests in the West Dongting Lake region from 2000 to 2018 using a reconstructed monthly Landsat NDVI time series. The multi-type forest changes, including conversion from forest to another land cover category, conversion from another land cover category to forest, and conversion from forest to forest (such as flooding and replantation post-deforestation), and land cover categories before and after change were effectively detected by integrating Breaks For Additive Seasonal and Trend (BFAST) and random forest algorithms with the monthly NDVI time series, with an overall accuracy of 87.8%. On the basis of focusing on all the forest regions extracted through creating a forest mask for each image in time series and merging these to produce an 'anytime' forest mask, the spatiotemporal dynamics of forest were analyzed on the basis of the acquired information of multi-type forest changes and classification. The forests are principally distributed in the core zone of West Donting Lake surrounding the water body and the southwestern mountains. The forest changes in the core zone and low elevation region are prevalent and frequent. The variation of forest areas in West Dongting Lake experienced three steps: rapid expansion of forest plantation from 2000 to 2005, relatively steady from 2006 to 2011, and continuous decline since 2011, mainly caused by anthropogenic factors, such as government policies and economic profits. This study demonstrated the applicability of the integrated BFAST method to detect multi-type forest changes by using dense Landsat time series in the subtropical wetland ecosystem with low data availability. [ABSTRACT FROM AUTHOR]