JOURNAL OF NATURAL RESOURCES ›› 2019, Vol. 34 ›› Issue (12): 2643-2657.doi: 10.31497/zrzyxb.20191213

• Resource Evaluation • Previous Articles     Next Articles

Ecological vulnerability assessment for a transboundary basin in Central Asia and its spatiotemporal characteristics analysis: Taking Amu Darya River Basin as an example

CHEN Tao1,2(), BAO An-ming1(), GUO Hao1,2, ZHENG Guo-xiong1,2, YUAN Ye1,2, YU Tao1,2   

  1. 1. State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, CAS, Urumqi 830011, China
    2. University of Chinese Academy of Sciences, Beijing 100049, China
  • Received:2019-04-20 Revised:2019-08-28 Online:2019-12-28 Published:2019-12-28

Abstract:

Quantitative assessment and long-term analysis of ecological vulnerability (EVI) are greatly important for understanding the dynamics of regional ecological environment and guiding ecological environmental protection and restoration. However, in the previous studies, there was rare assessment for ecological vulnerability of the special area of a transboundary basin. In this paper, the Amu Darya River Basin was used as the study area and 11 indicators were selected to reflect the vegetation, hydrology, climate, topography, soil and human activities. After the collinearity diagnostics, an ecological vulnerability assessment system for the study area was constructed. Further, subjective weight method and objective weight method was combined to determine the weight of all indexes, and quantitative estimation for the ecological vulnerability and the spatiotemporal characteristics analysis of the study area from 1990 to 2015 were conducted. The results showed that: (1) The ecological environment of the study area showed a deteriorating trend, and most of the areas were in a heavy vulnerable situation; the average proportion of heavy vulnerability during the study period was 46.40%. The proportion of extreme vulnerability also increased from 2.58% in 1990 to 16.97% in 2015, an increase of 14.39% over the past 25 years. (2) The ecological vulnerability of the study area varied greatly among different land cover types. The EVI value of grassland changed the most, the ecological environment of bare land was the most vulnerable, and the ecological vulnerability of forest was the lowest. In all, the ecological vulnerability levels among different land cover types were in an oreder of bare land > shrub > grassland > cropland > urban land > forest. (3) The relationship between EVI and topographical factors indicated that the area with lower elevation and smaller slope or higher elevation and larger slope was the most vulnerable regions, while the area with low vulnerability was mainly distributed in the regions at an altitude of 2500-3500 m or on a slope of 15-25°.

Key words: remote sensing, ecological vulnerability, improved Entropy weighted method, spatiotemporal characteristics, Amu Darya River Basin, Central Asia