Influence of Surface Water on Desert Vegetation Expansion at the Landscape Scale: A Case Study of the Daliyabuyi Oasis, Taklamakan Desert

Abstract

Surface water is an important factor affecting vegetation change in desert areas. However, little research has been conducted on the effects of surface water on vegetation expansion. In this study, the annual spatial distribution range of vegetation and surface water in the Daliyabuyi Oasis from 1990 to 2020 was extracted using Landsat time-series images. Based on multi-temporal and multi-scale remote sensing images, several plots were selected to demonstrate the process of landform change and vegetation expansion, and the influence of surface water on vegetation expansion was analyzed. The results show that the vegetation distribution and surface water coverage have increased from 1990 to 2020; and surface water is a critical factor that drives the expansion of vegetation. On the one hand, surface water in the study area was essential for reshaping the riparian landform, driving the transformation of dunes into floodplains, and increasing the potential colonization sites for vegetation. However, landform changes ultimately changed the redistribution of surface water, ensuring that enough water and nutrients provided by sediment were available for plant growth. Our study provides a critical reference for the restoration of desert vegetation and the sustainable development of oases.

Link between the aboveground and belowground biomass allocation with growing of Tamarix sp. seedlings in the hinterland of Taklimakan Desert, China

“…The study area is located at the Daryaboyi Oasis in the hinterland of the Taklamakan Desert, Xinjiang, China ( Fig 1 ). It has a geographical location of 38°24’–38°34’N, 81°56’–81°90’E, an altitude of 1,100–1,300 m, and an area of approximately 324 km 2 ‎[ 33 , 34 ]. This area is part of a typically arid continental climate, with an average annual precipitation of less than 10 mm; the average relative humidity is 40.2%; the annual potential evaporation is 2,480 mm; the average annual temperature is 12.1°C, and there is a large difference in temperature between day and night ‎[ 22 ].…”

The combined effect of surface water and groundwater on environmental heterogeneity reveals the basis of beta diversity pattern in desert oasis communities

“…In this study, satellite remote sensing technology was used to obtain the water indices of Landsat 8 data in the past five years, and after threshold segmentation, the distribution law and frequency characteristics of surface water during interannual variation were clarified [ 40 ]. The purpose of this method was to quantify the disturbance effect of surface water on the community, therefore the formula was established as follows: …”

Influence of Climate, Topography, and Hydrology on Vegetation Distribution Patterns—Oasis in the Taklamakan Desert Hinterland

“…This selection considered the degree of numerical differentiation between the surface water image elements and background image elements, that is, the numerical size difference, and the larger the difference, the more conducive it is to the application of automatic thresholding to determine the method of extracting the distribution range of the water bodies and obtaining a better accuracy. Based on a previous analysis [21], the AEWI no shadow water body index is the most effective. Mapping the spatial distribution of the surface water was achieved using the maximum entropy threshold segmentation method (Figure 3).…”

“…Relatively abundant and stable water sources in oases provide the necessary water and nutrients for vegetation growth and are prerequisites for the development of natural oases in arid zones [20]. Surface water and its distribution are key factors shaping the spatial vegetation distribution patterns of oases [21].…”