# Change and Driving Factor Analysis of Eco-Environment of Typical Lakes in Arid Areas
## 1 Introduction  
Lakes play a vital role in maintaining biodiversity and rich flora and fauna resources in arid regions [1]. Lakes are a link among the interactions of the Earth's various spheres, as well as important indicators of climate change and human activities [2, 3]. In recent years, under the dual effects of global climate change and human social activities, the natural environment has been severely damaged, and the ecological problems caused by the long-term reduction in the inflow water volume of inland lakes have become more prominent [4]. The decline in lakeside vegetation has led to a decrease in biodiversity, shrinking lake and wetland areas, and land desertification [5, 6]. Especially in the inland river basins in arid regions, lakes play an irreplaceable role in maintaining the benign cycle of the ecosystem, improving local climate, and maintaining biodiversity [7], thus effectively improving landdesertification. As an important indicator of lake changes, the area can intuitively reflect the spatiotemporal distribution characteristics of water resources in the region [8]. Changes in the water area can directly affect the local ecological and social benefits [9]. Changes in lakes can sensitively record changes in local climate and human activities and comprehensively reflect the ecological environment quality of a certain region [10]. Studies on inland lakes in arid regions have shown that ecological water conveyance is directly related to maintaining the area of these lakes and restoring local ecology [11; 12; 13]. In arid zones, lakes are inextricably linked to the local ecological environment, and both are mutually constrained. The quality of the ecological environment can reflect the overall indicators of a region, such as biodiversity, the degree of land desertification, and the status of water resources such as lakes and rivers. To protect ecological security in arid regions, the Chinese government has implemented ecological water conveyance in various areas, such as the Tarim River, Shiyang River, and Heihe River basins [14; 15; 16]. Currently, previous scholars have mainly conducted research on the changes in lake ecological environment quality after ecological water conveyance in three aspects: Some scholars have evaluated vegetation recovery after ecological water conveyance based on ecosystem functional indicators, such as net primary productivity (NPP) [17], gross primary productivity (GPP) [18], water use efficiency (WUE) of vegetation [19], and normalized difference vegetation index (NDVI) [20]. Some scholars have evaluated changes in hydrological conditions after ecological water conveyance, such as changes in groundwater depth, groundwater quality, and surface water area [21; 22; 23]. Others have evaluated soil quality after ecological water conveyance using indicators such as the temperature vegetation dryness index (TVDI) [24], soil nutrients [25], and soil moisture [26]. Researchers have found that after ecological water conveyance, the number of natural vegetation species, growth, and vegetation coverage in the local area have gradually recovered [27; 28; 29] and biodiversity has continuously increased [30; 31]. In most areas where ecological water conveyance has been implemented, hydrological conditions have significantly improved; water quality has greatly improved; and groundwater levels have significantly increased [32]. Soil quality has become more moist, and soil nutrient content is higher closer to rivers [25; 33]. In order to achieve ecological water conveyance, Daxhaizi Reservoir was established to regulate water resources and to convey water from the Tarim River to Lake Taitema. So far, the Tarim River ecological water conveyance project has been implemented for more than 20 years, and studies on the middle and lower reaches of the Tarim River and its terminal lake, Lake Taitema, have been carried out from several perspectives, but without correlation analysis among them, mainly focusing on vegetation, hydrology, soil properties, and climate evolution.