Influence of natural factors and land use change on changes in the main lake area in China over the past 30 years

Abstract

Being one of the main elements of water resources, lakes perform an indispensable part in social production as well as in life. During recent decades, the area of the lake has significantly altered due to global climate variability and growing intensity of the anthropogenic activities. The shrinkage and expansion of lakes have seriously affected both its ecological function and the sustainable development of the regional economy. With this study, we obtain the areas of 38 lakes in China by using the Landsat serial of remote-sensing satellite images in the period 1989–2019 in combination with NDWI water body index and Otsu adaptive thresholding method according to Google Earth Engine (GEE) to explore the trends of lake area changes and related drivers. The outcomes revealed that (1) the overall lake area in the Yunnan-Guizhou Plateau Lake Region (YGP_LR) showed a decreasing trend during the period from 1989 to 2019; the total area of the two lakes(Selin Co and Yangzhuoyong Co) in the Qinghai-Tibet Plateau (QTP_LR) shows an expanding trend; the area of Wulungu Lake in the Mong-Xin Plateau Lake Region (MXP_LR) and Xingkai Lake in the Northeast Plain and Mountain Lake Region (NPM_LR) on a tendency to expand; the area of lakes in the Eastern Plain Lake Region (EP_LR) fluctuated greatly, and the overall area shows a decreasing trend. (2) The increase of temperature promoted the expansion of lake area fed by glacier melt. The increase of rainfall is conducive to the expansion of lake area. The lake area of YGP_LR and EP_LR is closely related to the conversion of other land use types. (3) The lake area of the QTP_LR (Selin Co, Yangzhuoyong Co) varies are mainly affected by climatic factors. Lake area changes in the YGP_LR, Northeast Plain and Mountainous Lake Region (Xingkai Lake), MXP_LR (Wulungu Lake), and EP_LR are influenced by a combination of both climatic changes and the activities of humans. Impact factors of area change in the NPM_LR (Xingkai Lake) need to be further explored.