Journal of Geographical Sciences ›› 2018, Vol. 28 ›› Issue (8): 1099-1112.doi: 10.1007/s11442-018-1544-3

• 研究论文 • Previous Articles     Next Articles

Determination of land salinization causes via land cover and hydrological process change detection in a typical part of Songnen Plain

Zhiyong WANG1,2(), Lijuan LI1,*()   

  1. 1. Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing 100101, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2017-10-12 Accepted:2018-01-26 Online:2018-08-10 Published:2018-12-26
  • Contact: Lijuan LI E-mail:wangzy8809@gmail.com;lilj@igsnrr.ac.cn
  • About author:

    Author: Wang Zhiyong (1988-), PhD Candidate, specialized in water and salt cycle. E-mail: wangzy8809@gmail.com

  • Supported by:
    Key Deployment Project of CAS, No.KFZD-SW-314;National Natural Science Foundation of China, No.91547114

Abstract:

Causes of land salinization were determined via land cover and hydrological process change detection in a typical part of Songnen Plain. The area of saline land increased from 4627 km2 in 1980 to 5416 km2 in 2000, and then decreased to 5198 km2 in 2015. The transformation between saline land and other land covers happened mainly before 2000, and saline land had transformation relationship mainly with cropland, grassland, and water body. From 1979 to 2007, groundwater depth fluctuated to increase and was mainly deeper than 3.3 m. Spatially, the area of the region where groundwater depth was deeper than 3.3 m increased from 46.7% in 1980 to 84% in 2000, while the area of the region almost occupied the whole region after 2000. Precipitation and evaporation changed little, while runoff decreased substantially. Shallow groundwater, change of cropland, grassland, and water body induced from human activities and decrease of runoff and increase of irrigation and water transfer from outer basin were the main reasons for land salinization before 2000. After 2000, groundwater with relatively great depth could not exert great influence on land salinization. Protection of grassland and wetland prevented the increase of the area of saline land.

Key words: change detection, hydrological process, land cover, land salinization, Songnen Plain