Oasis Change Characteristics and Influencing Factors in the Shiyang River Basin, China

Abstract

The variability of the natural environment and the complexity of human activities result in dynamic changes in oasis areas, which is directly related to the sustainable development of arid and semi-arid areas. In order to better balance economic development and environmentally sustainable development, based on land use data and social and economic data from 1980 to 2015, this paper analyzed the oasis change characteristics under natural and human factors in the Shiyang River Basin in Northwest China. The results indicated that the oasis in the Shiyang River Basin showed an expansion trend from 1980 to 2015, with the expansion mainly occurring in the diluvial and alluvial fan, and along the middle and lower reaches of the river. The oasis changed actively in areas at an elevation of 1350 m, with a slope of 2°, at the distance of 1500 m to rivers, and with precipitation of 120 mm and temperature of 15 °C. Furthermore, the oasis mainly evolved towards gentler slopes and lower altitudes, and migrated closer to rivers before 1992 and farther away from rivers afterwards. Population growth and economic development were the important inducers of oasis change, and government policies on agricultural benefits and ecological conservation also influenced the oasis change, especially after 2000. The evolution patterns of oasis distribution revealed in this study can provide a reference for promoting oasis ecological restoration and sustainable development.

Study on the Spatial and Temporal Trends of Ecological Environment Quality and Influencing Factors in Xinjiang Oasis

“…It was found that the expansion of arable land and construction land is a key factor leading to the ecological decline of the Shule River [28], and this relevant point of view was also confirmed in the Manas River basin [27]. For this reason, artificial oases have been proposed as a key factor leading to the decline in ecological environment quality [2]. In order to prevent ecological degradation, natural oases need to be protected and the continued expansion of artificial oases must be curbed.…”

“…In the unchanged oasis condition, the area of RSEI increase is only 31.5 thousand, accounting for 16.15% of the total area of the oasis, mostly distributed in the upper and middle reaches of the oasis with better water conditions, which is dominated by the increase in ecological quality of AO, with an area of 22.2 thousand km 2 , and the area of NO is only 0.930 thousand km 2 ; the expansion of the oasis brings about the enhancement of the RSEI, which accounts for 34.3 thousand km 2 , accounting for 0.930 thousand km 2 of the total oasis km 2 , accounting for 17.58% of the total oasis area, with an area of 26,400 km 2 for AO and 0.79 million km 2 for NO. On the contrary, the oasis expansion caused a decrease in the RSEI value of the area of 18.43%, with an area of 14,700 km 2 for AO and 21,200 km 2 for NO, which was mainly distributed in the periphery of the existing oasis, and subject to the resource and environmental constraints. This type of change is mainly distributed in the periphery of the existing oasis, and due to the limitation of resources and environment, the transformation between AO and NO is more frequent, and the ecological quality of the oasis is lower.…”

“…The degradation of the quality of the ecological environment slowed down from 2005 to 2010, with the degraded area in the four periods being 55,900 km 2 , 30,600 km 2 , 52,200 km 2 , and 57,100 km 2 . The area of improvement in the quality of the ecological environment being 26,700 km 2 , 52,200 km 2 , 28,700 km 2 , and 22,500 km 2 .…”

“…Oases arid zones are important places for human survival and development [1]. In the context of global and regional ecosystems under the influence of climate change and human activities, scientific assessment of dry zone ecosystems plays an important role in environmental governance and sustainable development [2]. With rapid economic development, conflicts and problems between human beings and ecosystems are becoming more and more prominent [3].…”

Quantitative analysis of desertification driving mechanisms in the Shiyang River Basin: Examining interactive effects of key factors through the Geographic Detector Model

“…However, since the 1950s, desertification has increased in China, peaking between the 1970s and early 1980s, then later started ecosystem rehabilitation projects [15]. Particularly the Shiyang River Basin, as a pivotal in natural resource reserves in the Hexi Corridor zone, has also been subject to extreme natural and excessive anthropogenic pressures leading to rapid ecological deterioration and desertification at an unprecedented rate [21,22]. For example, temperature increases and reduced glacial meltwater in the Qilian Mountains have led to a water supply shortage for the past few decades [23].…”