Importance of stopping groundwater irrigation for balancing agriculture and wetland ecosystem

Abstract

The surge in agricultural water consumption to ensure food security in China has severely hampered the survival of wetland ecosystems. People ignore the importance of “lungs” in the process of meeting the needs for “stomach”. In this study, we quantified the direct and indirect impacts of agricultural water consumption on wetland plant species using Characterization Factors (CFs) and identified their contributions in the three historical periods in the Sanjiang Plain, China. The total potential losses of wetland plant diversity were calculated, and the wetland benefits were evaluated based on the “National Sustainable Agriculture Plan for 2030”. Results indicated that the direct impact of the amount of irrigation water on plant species enhanced, while the indirect impact of groundwater abstraction declined with a drop in one order of magnitude. However, the wetland plant diversity was more responsive to 1 m3 of groundwater abstraction than 1 m3 of irrigation water in all three periods. The agricultural water consumption resulted in more than 120 wetland plant species-eq potential loss from 1987 to 2018, where irrigation water contributed for 57% and groundwater abstraction behavior contributed for 43% loss. The plant diversity loss due to groundwater abstraction was avoidable. By 2030, the wetland plant diversity will be restored by 15.5% according to the national policy, almost all of which comes from the contribution of eliminating the groundwater use. The comprehensive implementation of surface water irrigation, as a practical alternative to groundwater source, is an effective approach to alleviate the contradiction of food security and wetland protection.

Keywords

• Agricultural water consumption
• Wetland ecosystem
• Groundwater abstraction
• Food security