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Understanding the relationship of hydrothermal conditions to vegetation changes is conducive to revealing the feedback mechanism connecting climate variations and vegetation. Based on the methods of Theil–Sen median analysis, and the Mann–Kendall trend test, this research investigated the spatiotemporal vegetation dynamics in Central Asia using the Normalized Difference Vegetation Index (NDVI) and grid climate data from 1982 to 2015. Further, the contributions of hydrothermal conditions to vegetation changes were quantified using a boosted regression tree model (BRT). The results demonstrated that the spatiotemporal characteristics of vegetation dynamics exhibited significant differences in different seasons, and most pixels showed increasing trends in the growing season and spring. Boosted regression tree analysis indicated that the contributions of hydrothermal conditions to vegetation dynamics exhibited temporal and spatial heterogeneity. During the annual, growing season, and summer examination periods, the contribution value of the increase in warming conditions (temperature or potential evapotranspiration) to vegetation degradation in the region due to the hydrothermal tradeoff effect (water) was 49.92%, 44.10%, and 44.95%, respectively. Moreover, the increase in warming conditions promoted vegetation growth, with a contribution value of 59.73% in spring. The contribution value of the increase in wetting conditions (precipitation or soil moisture) to vegetation growth was 48.46% in northern Central Asia, but the contribution value of the increase in warming conditions to vegetation degradation was 59.49% in Ustyurt Upland and the Aral Sea basin in autumn. However, the increase in warming conditions facilitated irrigation vegetation growth, with a contribution value of 59.86% in winter. The increasing potential evapotranspiration was the main factor affecting vegetation degradation in the Kyzylkum Desert and Karakum Desert during the annual, growing season, and autumn examination periods. Precipitation and soil moisture played decisive roles in vegetation dynamics in northern Central Asia during the growing season, summer, and autumn. This research provides reference information for ecological restoration in Central Asia. [ABSTRACT FROM AUTHOR]

Intense human activities in the Aral Sea Basin have changed its natural distribution of land use. Although they provide certain economic benefits, these anthropogenic influences have led to the rapid shrinkage of the Aral Sea, severely affecting the region's ecosystem. However, the spatiotemporal variability of the Aral Sea Basin's Ecosystem Service Values (ESVs) is not well understood. In this study, we used 300- meter resolution land use maps from 1995, 2005, and 2015 and the Patch-generating Land Use Simulation (PLUS) model to predict the future land use patterns of the Aral Sea Basin in 2025. Simultaneously, we divided the Aral Sea Basin into three regions (upstream, midstream, and downstream) and evaluated the dynamic responses of their ESVs to Land Use and Land Cover (LULC) changes. The changes in the types of ecosystem services provided by the Aral Sea Basin, their trade-off, and synergistic relationships were analyzed by weighting their associations. The results showed that from 1995 to 2025, the grassland, urban, and cropland areas in the Aral Sea Basin will expand rapidly, while the areas covered by water bodies will shrink rapidly, causing a total loss of 31.97 billion USD. The downstream loss of 27.79 billion USD of the total amount is mainly caused by the conversion of water bodies to bare land. The ESVs of the middle region will increase by 6.81 billion USD, mainly due to the large amount of water extracted from the Amu Darya and Syr Darya Rivers in the middle regions of the Aral Sea Basin that are used to reclaim cultivated land and expand urban areas. The ESVs and areas experiencing land use changes in the upper regions are relatively small. At the same time, our results show that biodiversity, food production, and water regulation are the major ecosystem service functions, and account for 79.46% of the total ESVs. Of the ecosystem service relationships in the Aral Sea Basin, synergy accounts for 55.56% of the interactions, with a fewer amount of trade-off exchanges. This synergy mainly exists in the relationships involving water regulation, waste treatment and recreation, and culture and tourism. We propose protection measures that will coordinate eco-environmental protection efforts with socioeconomic development in the region in order to achieve the United Nations' sustainable development goals. [ABSTRACT FROM AUTHOR]

Intense human activities in the Aral Sea Basin have changed its natural distribution of land use. Although they provide certain economic benefits, these anthropogenic influences have led to the rapid shrinkage of the Aral Sea, severely affecting the region's ecosystem. However, the spatiotemporal variability of the Aral Sea Basin's Ecosystem Service Values (ESVs) is not well understood. In this study, we used 300-meter resolution land use maps from 1995, 2005, and 2015 and the Patch-generating Land Use Simulation (PLUS) model to predict the future land use patterns of the Aral Sea Basin in 2025. Simultaneously, we divided the Aral Sea Basin into three regions (upstream, midstream, and downstream) and evaluated the dynamic responses of their ESVs to Land Use and Land Cover (LULC) changes. The changes in the types of ecosystem services provided by the Aral Sea Basin, their trade-off, and synergistic relationships were analyzed by weighting their associations. The results showed that from 1995 to 2025, the grassland, urban, and cropland areas in the Aral Sea Basin will expand rapidly, while the areas covered by water bodies will shrink rapidly, causing a total loss of 31.97 billion USD. The downstream loss of 27.79 billion USD of the total amount is mainly caused by the conversion of water bodies to bare land. The ESVs of the middle region will increase by 6.81 billion USD, mainly due to the large amount of water extracted from the Amu Darya and Syr Darya Rivers in the middle regions of the Aral Sea Basin that are used to reclaim cultivated land and expand urban areas. The ESVs and areas experiencing land use changes in the upper regions are relatively small. At the same time, our results show that biodiversity, food production, and water regulation are the major ecosystem service functions, and account for 79.46% of the total ESVs. Of the ecosystem service relationships in the Aral Sea Basin, synergy accounts for 55.56% of the interactions, with a fewer amount of trade-off exchanges. This synergy mainly exists in the relationships involving water regulation, waste treatment and recreation, and culture and tourism. We propose protection measures that will coordinate eco-environmental protection efforts with socioeconomic development in the region in order to achieve the United Nations' sustainable development goals., Competing Interests: Jun Liu is an employee of the TripleSAI Technology, Shenzhen, China., (©2021 Chen et al.)