Welcome to Chinese Journal of Applied Ecology! Today is Share:

Chinese Journal of Applied Ecology ›› 2021, Vol. 32 ›› Issue (2): 433-440.doi: 10.13287/j.1001-9332.202102.010

• Special Features of Grassland Ecology • Previous Articles     Next Articles

Distribution characteristics of soil particle size in alpine steppe and alpine meadow in the source region of the Yangtze River, China

AN Ke-jian, WEI Xia*, ZHAO Heng-ce, HE Yan, YU Wen-zhu   

  1. College of Earth Environmental Sciences, Lanzhou University, Lanzhou 730000, China
  • Received:2020-08-02 Accepted:2020-12-01 Online:2021-02-15 Published:2021-08-15
  • Contact: *E-mail: weix@lzu.edu.cn
  • Supported by:
    National Natural Science Foundation of China (51679115), the Open Foundation of Ministry of Education Key Laboratory of Western China’s Environmental System, Lanzhou University (lzujbky-2018-kb01), and the Fundamental Research Funds for the Central Universities, Lanzhou University (lzujbky-2018-kb01)

Abstract: To explore the heterogeneity of spatial distribution and particle size distribution (PSD) in the main underlying surface soil in the source area of the Yangtze River, we used the fractal theory to describe the soil particle size distribution of alpine steppe and alpine meadow, and analyzed the difference of fractal dimension characteristics of soil of two different underlying surface and its relationship with soil particle composition. The results showed that soil particle size in the study area was mainly concentrated in 100-800 μm. The single fractal dimension (DV) of alpine steppe soil was 2.429-2.508, and that of alpine meadow soil was 2.697-2.743. The soil texture of alpine steppe was coarse, while that of alpine meadow soil was fine. Soil texture was the finest in the 20-30 cm depth, and the coarsest in the 0-10 cm layer. The multi-fractal dimension (capacity dimension D0, information entropy dimension D1, correlation dimension D2) of alpine steppe (0.896-0.961, 0.828-0.887, 0.725-0.819) was higher than that of alpine meadow (0.890-0.914, 0.693-0.744, 0.540-0.603). Compared with the alpine meadow, the alpine steppe had wider soil PSD, more complex soil structure, and higher soil heterogeneity. DV was positively correlated to clay and silt contents, and negatively correlated to sand content. D1 and D2 were negatively correlated with clay and silt contents, and positively correlated with sand content. Sand content was the main factor accounting for the non-uniform distribution of PSD and the changes of fractal dimension.

Key words: particle size distribution, fractal feature, alpine steppe, alpine meadow, source region of the Yangtze River