Spatial-temporal variation of ecosystem water use efficiency in Beijing's suburban region

3rd International Conference on Water Resource and Environment

地球科学;生态环境科学

Mi, F.^1 ; Zhang, Q.^1 ; Zhang, X.C.^1 ; Yuan, S.B.^2 ; Lu, N.^3 ; Yan, N Na^4

School of Economics and Management, Beijing Forestry University, 35 Qinghua East Rd, Haidian District, Beijing

100083, China^1

Afforestation Office, Beijing Gardening and Greening Bureau, 1 Xiaohuangzhuang North St, Dongcheng District, Beijing

100013, China^2

State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Science, Chinese Academy of Sciences, 18 Shuangqing Rd, Haidian District, Beijing

100085, China^3

Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, West Beichen Road, Chaoyang District, Beijing

100101, China^4

关键词: Carbon sequestration;    Ecological engineering;    Ecosystem diversity;    Ecosystem functions;    Remote sensing data;    Spatial and temporal variation;    Spatial variations;    Water-use efficiency;   

Others  :  https://iopscience.iop.org/article/10.1088/1755-1315/82/1/012091/pdf
DOI  :  10.1088/1755-1315/82/1/012091

学科分类：环境科学（综合）

来源: IOP

【 摘 要 】

Suburban ecosystem has multiple functions such as soil conservation and water regulation, which are critical for the welfare of human beings in the city. Water use efficiency (WUE) is an important indicator of ecosystem function that represents the amount of productivity per unit mass of evapotranspiration (ET). Improving WUE of suburban ecosystem is significant to climate regulation by carbon sequestration and water consumption, especially for cities with severe water shortage like Beijing, the capital of China. Based on remote sensing data, this paper examined the spatial and temporal variations in WUE in Beijing's suburban region from 2002 to 2010. The results showed that the average annual WUE was 0.868 g C mm-1m-2. It has large spatial variation with the minimum of 0.500 g C mm-1m-2in the Miyun District. During the study periods, the area with significant increasing trend of WUE was 63.2% of the total suburban region. In terms of ecosystem type, the value of WUE was following the sequence, deciduous coniferous forest (0.921g C mm-1m-2) > mixed forest (0.887g C mm-1m-2) > deciduous broadleaf forest (0.884 g C mm-1m-2) > shrubland (0.860 g C mm-1m-2) > evergreen coniferous forest (0.836 g C mm-1m-2) > grassland (0.830 g C mm-1m-2). As ET was similar among the ecosystems, the difference in WUE was mainly due to the discrepancy of NPP. We found that NPP significantly correlated with the diversity of ecosystem type (represented by Shannon-Wiener index). Our results suggest that ecological engineering construction, scientific ecosystem type selection, ecosystem diversity improvement and drought-resistant species cultivation are conductive to improve ecosystem WUE in Beijing's suburban region.