Defining an Ecologically Ideal Shallow Groundwater Depth for Regional Sustainable Management: Conceptual Development and Case Study on the Sanjiang Plain, Northeast China
2015
Wang, Xihua | Zhang, Guangxin | Xu, Yi Jun | Shan, Xiangjun
The depth and fluctuation of shallow groundwater influence water supply to land surface vegetation. Knowledge of an ecologically ideal depth range of shallow groundwater for a vegetation ecosystem can be crucial for sustainability of regional water resource management and ecological conservation. In this study, we developed a conceptual model that identifies an upper and a lower boundary of shallow groundwater for sustaining present vegetation ecosystems, termed ecologically ideal shallow groundwater depth (EISGD). We then applied the conceptual model to the Sanjiang Plain (10.9 × 10⁴ km²) in northeast China in order to gain insights into sustainable shallow groundwater usage in this intensively irrigated agricultural region. Using soil capillary rise, plant rooting depth, extinction depth, and the actual groundwater depth, we identified an upper boundary range of EISGD between 0.5 and 2.8 m and a lower boundary range of EISGD between 2.0 and 14.3 m for different vegetation covers in the Sanjiang Plain. Based on the ranges, we estimated allowable shallow groundwater withdrawal (i.e., without degrading the present vegetation ecosystem) for the region and identified an area of 2.54 × 10¹⁰ m² with a total of 9.14 × 10⁸ m³ water deficit. Currently, the entire Sanjiang Plain has a total volume of 45.30 × 10⁸ m³ EISGD allowable shallow groundwater withdrawal, thus the plain’s northeast region can be considered as having a high allowable pumping capacity. This study demonstrates that application of an EISGD concept can be useful for developing regional management strategies and plans for ecological protection and sustainable groundwater utilization.
显示更多 [+] 显示较少 [-]