Monitoring dynamics and driving forces of lake changes in different seasons in Xinjiang using multi-source remote sensing

Abstract

Lakes are important for ensuring the development of the regional economy and ecological security. Based on MODIS and Landsat TM/OLI remote sensing images captured in 2005-2015 and a Combined Water Index (CWI), this paper extracted information on changes in the temporal and spatial characteristics and driving forces for lake areas in Xinjiang during past 11 years in different seasons (April, July and September). The results showed that over this time period, the area of the lakes exhibited an increasing trend. The largest surface area usually occurred in April, and the lowest value was measured in September. The lake shrinkage area in Xinjiang occurred mainly in Northern Xinjiang and the northeastern region of Southern Xinjiang, whereas the lake expansion area was concentrated in Eastern Xinjiang. Seasonal changes in Manas, Kanas, Barkol, Arkatag, Arik and Ebinur Lakes showed higher trends. Extracted the lake area based on the MODIS and TM/OLI image were analyzed, and both had a good corresponding relationship. The minimum R 2 was 0.548, and maximum RMSE was 44.1km 2 . Therefore, it was feasible to use MODIS to extract lake area. These changes in lake area resulted from both natural factors and human activities, and coupled effects greatly accelerated local environmental changes.

Recent Lake Area Changes in Central Asia

“…Lake ice was identified as part of lake area for April in this paper, the present study noted that lakes area were larger than that reported in the existing literature due to different reflectivity for ice and water 2,17 . There may be also some uncertainty with large water bodies, as the spatial resolution of MODIS is 500 m each day, which is relatively low.…”

“…The seasonal variation trend was similar as lake area obtained by Jing et al . 17 , such as Ebi Lake, Ulungu Lake and Ayakkum Lake. Bai et al .…”

“…Jing et al . 17 extracted 12 lakes areas with a combined water index with MOD09A1 dataset in different seasons (April, July and September) in the year 2005–2015, but that only nearly 10-years long. Klein et al .…”

Expansion of typical lakes in Xinjiang under the combined effects of climate change and human activities

“…Lakes are important reservoirs of water resources in arid areas and an important part of the water cycle in arid areas (Song et al, 2013;Song et al, 2013;Kaplan and Avdan, 2017). They are among the most sensitive geographical units in response to global climate change and are also affected by human activities (Jing et al, 2018). In recent decades, inland lakes have undergone drastic changes due to natural environmental changes and human activities (Feng et al, 2016;Deng and Chen, 2017;Deng et al, 2022).…”

“…In addition, there are still few detailed analyses of changes in different lakes and the quantitative impact of local climate and human activities (Yu et al, 2020). The lakes in Xinjiang show different change trends at different altitudes (Jing et al, 2018); with the influence of complex topographic and geomorphic conditions, the types of lakes in the region are diverse. Lakes are distributed in different geomorphic types such as plains (altitude <1,500 m), mountains (1,500 m <altitude <3,500 m), and plateaus (altitude >3,500 m).…”