Chin J Plant Ecol ›› 2021, Vol. 45 ›› Issue (5): 467-475.DOI: 10.17521/cjpe.2020.0288

Special Issue: 遥感生态学

• Research Articles • Previous Articles     Next Articles

Changes in the pattern of an alpine wetland landscape in Maqu County in the first meander of the Yellow River

XUE Peng-Fei1,2, LI Wen-Long1,2,*(), ZHU Gao-Feng3, ZHOU Hua-Kun4, LIU Chen-Li1,2, YAN He-Piao1,2   

  1. 1State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agriculture Science and Technology, Lanzhou University, Lanzhou 730000, China
    2Key Laboratory of Grassland Livestock Industry Innovation, Ministry of Agriculture and Rural Affairs, Lanzhou University; Engineering Research Center of Grassland Industry, Ministry of Education, Lanzhou University, Lanzhou 730000, China
    3College of Earth and Environment Sciences, Lanzhou University, Lanzhou 730000, China
    4Northwest Institute of Plateau Biology, Chinese Academy of Sciences, Xining 810008, China
  • Received:2020-08-21 Accepted:2021-01-12 Online:2021-05-20 Published:2021-03-09
  • Contact: LI Wen-Long
  • Supported by:
    the National Key R&D Program of China(2018YFC0406602);the National Natural Science Foundation of China(41471450);the Fundamental Research Fund for the Central Universities(lzujbky-2021);the Earmarked Fund for China Agriculture Research System(CARS-34);the Natural Science Foundation of Qinghai Province(2019-ZJ-908)

Abstract:

Aims The alpine wetland is one of the most important sites for ecological and water conservation in Qingzang Plateau, and also an effective regulator of the local climate. Research is needed to understand the dynamics and drivers of changes in this alpine wetland landscape.
Methods This study was conducted with combination of methods in remote sensing image analysis, GIS spatial analysis and landscape attributes analysis. Changes in the alpine wetland patterns in Maqu County, which is located in the first meander of the Yellow River, was determined for six periodic samplings from 1995 to 2018.
Important findings The alpine wetland area in Maqu County continuously degraded from 1995 to 2010, and decreased by 18 680.31 hm2 over the period. From 2010 to 2018, the wetland area increased. Compared with the level in 1990s, the wetland area has generally declined since the beginning of the 21st century. From 1995 to 2010, the patch number and density of the wetland increased continuously, but the average patch size decreased, with increased degree of landscape fragmentation. In contrast, from 2010 to 2015, the patch number and density of wetland decreased. From 2015 to 2018, the patch number and density of wetland increased, and the average patch size first increased and then decreased, with the landscape fragmentation first decreased and then increased. Both the Shannon diversity index and evenness index showed a downward trend from 1995 to 2010; the landscape structure tended to be simpler and the distribution of landscape types became more clustered. From 2010 to 2018, the Shannon diversity and evenness indices showed an upward trend; the landscape structure tended to be more complex, and the landscape types became more diverse and dispersed. Further analyses revealed that the main factors driving the changes in the alpine wetland landscape patterns in the first meander of the Yellow River are evaporation and precipitation, followed by human activities such as the population and the quantity of large livestock. Climate is the main factor driving the changes in the alpine wetland area in the first meander of the Yellow River. Intensive human economic activities have aggravated the wetland changes to some extent.

Key words: alpine wetland, landscape pattern, random forest algorithm, driving force analysis, wetland change