Liang, YJ; Liu, LJ; Hashimoto, S (2020). Spatiotemporal analysis of trends in vegetation change across an artificial desert oasis, Northwest China, 1975-2010. ARABIAN JOURNAL OF GEOSCIENCES, 13(15), 742.

Vegetation change has become a worldwide environmental concern. Artificial desert oases in the Northwest China are among the most ecologically sensitive environments and are also a repository of ecosystem services by relying on vegetation system. Over the last four decades, land transformation related to anthropogenic activities and climate change is among the main drivers of changing vegetation cover in Northwest China. In an oasis where field-based research is challenging due to diverse landscape and heterogenous relief, quantifying changes in vegetation system using remote sensing can provide available information regarding trends in vegetation cover and its linkages with driving forces. This study aimed to explore spatiotemporal dynamics of vegetation change through examining time series normalized difference vegetation index (NDVI) over the period 1975-2010 in an artificial desert oasis in Northwest China. A time series imagery derived from Landsat product was analyzed for the presence of trends in vegetation change. Using the nonparametric Sen's and Mann-Kendall methods, over 13.56% of oasis land surfaces were found to exhibit significant increasing trends, and almost 6.07% of oasis land surfaces were found to exhibit significant decreasing trends. The 80.38% spatial distribution of vegetation showed no change trends significantly. The relationships between the detected NDVI trends and land cover also were evaluated by using spatial mapping method. Results showed that the spatiotemporal pattern of vegetation change was consistent with the climate-related change of vegetation growing conditions and implementation of ecosystem management during the study period.