Exploring grassland ecosystem water use efficiency using indicators of precipitation and soil moisture across the Mongolian Plateau

作者：Xinyi Liu, Quan Lai, Shan Yin, Yuhai Bao, Song Qing, Sainbuyan Bayarsaikhan, Lingxin Bu, Li Mei, Zhi‐Ru Li, Jialong Niu, Yumeng Yang · 发表于：Ecological Indicators · 年份：2022 · DOI：10.1016/j.ecolind.2022.109207 · 被引用次数：39 · 研究领域：Plant Water Relations and Carbon Dynamics、Hydrology and Watershed Management Studies、Soil Moisture and Remote Sensing

Grassland ecosystem dominates in the Mongolian Plateau, mostly located in its arid and semi-arid regions. Although the ecosystem is an important source for agriculture, it is also a fragile system ecologically. This system is one of the most sensitive areas to global climate change. Precipitation (PPT) and soil moisture (SM) are important water sources in the grassland ecosystem, and their changes would greatly affect vegetation growth. This paper generates the precipitation use efficiency (PUE) and soil water use efficiency (SWUE) of Mongolian Plateau grassland based on multi-source remote sensing data to investigate the spatio-temporal distribution pattern and identify the driving factors. Results showed four main findings. Firstly, two water use efficiency (WUE) indicators show a generally increasing trend from 2000 to 2018, with average PUE and SWUE 1.07 gC·m−2·mm−1 and 1.03 gC/kg·H2O, respectively. They have similar spatial distribution patterns, consistent with the available water resources, decreasing from northeast to southwest. However, grassland vegetation growth is more sensitive to soil moisture than precipitation, and the dynamic change of SWUE is smoother and more significant than PUE. Secondly, due to the higher species richness, better vegetation biological characteristics and less severe growth environment, meadow grassland has the highest PUE and SWUE, followed by typical grassland and desert steppe. Thirdly, PUE and SWUE are relatively low in extremely arid...