Journal of Geographical Sciences ›› 2020, Vol. 30 ›› Issue (1): 164-176.doi: 10.1007/s11442-020-1721-z

• Special Issue: Global and Regional Land Surface Characteristics and Socio-economic Scenarios • Previous Articles    

Impacts of climate change and agricultural activities on water quality in the Lower Kaidu River Basin, China

BA Wulong1,2, DU Pengfei1,*(), LIU Tie2, BAO Anming2, CHEN Xi2, LIU Jiao3, QIN Chengxin1   

  1. 1. State Key Laboratory of Environmental Simulation and Pollution Control, School of Environment, Tsinghua University, Beijing 100084, China
    2. State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, CAS, Urumqi 830011, China
    3. School of Energy and Power Engineering, Xihua University, Chengdu 610039, China
  • Received:2018-07-02 Accepted:2018-12-27 Online:2020-01-25 Published:2020-03-25
  • Contact: DU Pengfei E-mail:dupf@tsinghua.edu.cn
  • Supported by:
    National Key Research and Development Program of China, No(2017YFC0404501);Tianshan Innovation Team Project of the Xinjiang Department of Science and Technology, No(Y744261)

Abstract:

In the context of climate change and over-exploitation of water resources, water shortage and water pollution in arid regions have become major constraints to local sustainable development. In this study, we established a Soil and Water Assessment Tool (SWAT) model for simulating non-point source (NPS) pollution in the irrigation area of the lower reaches of the Kaidu River Basin, based on spatial and attribute data (2010-2014). Four climate change scenarios (2040-2044) and two agricultural management scenarios were input into the SWAT model to quantify the effects of climate change and agricultural management on solvents and solutes of pollutants in the study area. The simulation results show that compared to the reference period (2010-2014), with a decline in streamflow from the Kaidu River, the average annual irrigation water consumption is expected to decrease by 3.84×10 8 m 3 or 8.87% during the period of 2040-2044. Meanwhile, the average annual total nitrogen (TN) and total phosphorus (TP) in agricultural drainage canals will also increase by 10.50% and 30.06%, respectively. Through the implementation of agricultural management measures, the TN and TP in farmland drainage can be reduced by 14.49% and 16.03%, respectively, reaching 661.56 t and 12.99 t, accordingly, and the increasing water efficiency can save irrigation water consumption by 4.41×10 8 m 3 or 4.77%. The results indicate that although the water environment in the irrigation area in the lower reaches of the Kaidu River Basin is deteriorating, the situation can be improved by implementing appropriate agricultural production methods. The quantitative analysis results of NPS pollutants in the irrigation area under different scenarios provide a scientific basis for water environmental management in the Kaidu River Basin.

Key words: climate change, agricultural management, non-point pollutants, SWAT, Kaidu River Basin, water quality