Identifying the spatio-temporal pattern of vegetation change and influencing factors on the Loess Plateau between 2000 and 2022
Quantifying the contributions of climate change and human activities to changes in vegetation is important in terms of regional ecological protection and future research on the Loess Plateau.However,in the case of areas with naturally regenerated vegetation,where there are no clearly visible indications of human activities and ecological processes are not significantly disturbed,not all relevant forms of human activity can be remotely detected.Therefore,modelling the intensity of human modification of natural ecosystems could provide a pathway for a better understanding of the questions concerning where and how much vegetation change occurs in areas with evidence of human activities or land-use change.In this study,we utilized the Normalized Difference Vegetation Index(NDVI)between 2000 and 2022 and land-use datasets(a spatial resolution of 30 m)collected in 2000,2010,and 2020 to distinguish areas with strong and weak anthropogenic interference on the Loess Plateau.In those areas with clearly visible human activity,we explored the relative contributions of climate change and human activity to vegetation dynamics.Taking the lagged duration variation between climate factors and vegetation growth into consideration,climatic factors influencing vegetation decadal dynamics were identified in the southern part of the Loess Plateau.The results are as follows:(1)With the implementation of the Three-North Shelter Forest Program,Grain-to-Green Program,and other ecological projects,the rate of vegetation restoration on the Loess Plateau slowed by 3.4％/10a during the period 2012-2022;however,the overall trend was an increase in vegetation.(2)In sensitive areas of vegetation restoration in the Loess Plateau,human activities with a relative contribution exceeding 65％were the dominant factors of vegetation variability in the areas with both intensive and weak human interference,which is approximately 2.0-fold higher than the contribution of climate change.(3)The interdecadal anomalies of precipitation in June were effective indicators of opposite west-east vegetation anomalies in the southern part of the Loess Plateau.Specifically,when precipitation increased by 10 mm in June,this southeastern part witnessed a decrease of 1.4％in NDVI in contrast with a 1.7％increase in the southwestern part.By coupling temporal and spatial information we have clarified the spatial distribution of trends and decadal variations in NDVI and its influencing factors.These observations from the Loess Plateau provide useful insights to help understand the relationship between vegetation change,climate change,and human activities on vegetation restoration globally or in other regions of China.
万方数据
维普
