A framework to assess the impact of ecological water conveyance on groundwater-dependent terrestrial ecosystems in arid inland river basins

Feng Huang; Xunzhou Chunyu; Danrong Zhang; Xi Chen; Carlos G Ochoa

doi:10.1016/j.scitotenv.2019.136155

A framework to assess the impact of ecological water conveyance on groundwater-dependent terrestrial ecosystems in arid inland river basins

Sci Total Environ. 2020 Mar 20:709:136155. doi: 10.1016/j.scitotenv.2019.136155. Epub 2019 Dec 16.

Authors

Feng Huang¹, Xunzhou Chunyu², Danrong Zhang³, Xi Chen⁴, Carlos G Ochoa⁵

Affiliations

¹ College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China. Electronic address: huangfeng1987@hhu.edu.cn.
² College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China.
³ College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China. Electronic address: 20030112@hhu.edu.cn.
⁴ College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China; Institute of Surface-Earth System Science, Tianjin University, Tianjin 300072, China. Electronic address: xichen@hhu.edu.cn.
⁵ College of Agricultural Sciences - Ecohydrology Lab, Oregon State University, Corvallis, OR 97331, USA. Electronic address: Carlos.Ochoa@oregonstate.edu.

PMID: 31884270
DOI: 10.1016/j.scitotenv.2019.136155

Abstract

Overexploitation of water resources at middle reaches has threatened downstream oasis in arid inland river basins. To achieve sustainable development, ecological water conveyance is one effective measure to reallocate water resources between socio-economic and natural systems. A comprehensive impact assessment of ecological water conveyance on groundwater-dependent ecosystems that are common in downstream inland river basins is needed. The present study integrated the technologies of remote sensing analysis, trend detection, and numerical simulation into a technical framework that identifies the spatial response and temporal dynamics of vegetation to groundwater changes induced by ecological water conveyance. The Normalized Difference Vegetation Index (NDVI) was used as a proxy to estimate vegetation. The structure of the framework we used is clear and reasonable. We used remote-sensing data and ground truth information, and a decision tree that incorporates an iterative self-organizing data analysis technique. The decision tree classifies the land cover into affected and unaffected areas, and the results indicate the spatial range of impact. The Mann-Kendall algorithm and Sen's slope detect the tendency in NDVI series that indicates the temporal response of vegetation. The Verhulst logistic function, combined with environment carrying capacity function, constitutes a simplified vegetation dynamic model that can be used to predict potential impact through scenario analysis. An application in the Shiyang River basin in Northwest China evaluated the performance and usefulness of the framework; the accuracy of the results suggested that the framework is effective and practical. Additional case studies are required to assess the reliability and applicability of the framework and identify the factors that affect assessment results beyond our case study in the Shiyang River basin.

Keywords: Arid inland river basins; Assessment framework; Ecological water conveyance; Groundwater depth; NDVI; Vegetation restoration.