Acta Geographica Sinica ›› 2023, Vol. 78 ›› Issue (9): 2256-2270.doi: 10.11821/dlxb202309009

• Global Change Impact and Adaptation • Previous Articles     Next Articles

Topographic regulatory role of vegetation response to climate change

XIONG Xueting(), LI Chuanhua(), CHEN Jiahao   

  1. College of Geography and Environmental Science, Northwest Normal University, Lanzhou 730070, China
  • Received:2023-04-03 Revised:2023-08-31 Online:2023-09-25 Published:2023-09-28
  • Contact: LI Chuanhua E-mail:xxt10744@163.com;lch_nwnu@126.com
  • Supported by:
    National Natural Science Foundation of China(42161058)

Abstract:

Topography largely contributes to the spatial heterogeneity of regional climate change and thus influences the response of vegetation to climate change. In this paper, using Three-River Headwaters Region of the Qinghai-Tibet Plateau as the study area, and structural equation modeling is utilized to explore the regulatory effect of topography factors on the Normalized Difference Vegetation Index through temperature and precipitation. The study shows that slope and aspect in the Three-River Headwaters Region mainly affect the response of vegetation to climate change by regulating precipitation, while elevation mainly affects the response of vegetation to climate change by regulating temperature. Elevation has the largest effect, which slows down the response of vegetation to climate change, with a total effect of -0.35; slope has the second largest effect, which intensifies the response of vegetation to climate change, with a total effect of 0.31; aspect has the smallest regulatory effect, with a total effect of 0.03; the total effect of topographic factors is -0.01, indicating that the three types of topographic factors have offsetting effects. In the Three-River Headwaters Region, the effect of topographic factors on vegetation regulation is the largest at slopes 5°-15°, shady slope and elevations 3000-3500 m, and their effects are 0.23, 0.08 and 0.39, respectively. At slopes 5°-15° and elevations 4500-5000 m, the aspect makes the vegetation respond to climate change the most by regulating precipitation; at slopes 5°-15°, shady slope and elevation lower than 4000 m, the elevation intensifies the vegetation response to climate by regulating temperature, and at elevation more than 4000 m, the elevation slows down the vegetation response to climate mainly by regulating precipitation. This paper can provide a basis for the study of the response pattern of mountain vegetation to climate change.

Key words: topography, NDVI, climate response, SEM, regulatory effect, Three-River Headwaters Region