Arid Zone Research ›› 2024, Vol. 41 ›› Issue (12): 2143-2153.doi: 10.13866/j.azr.2024.12.15

• Ecology and Environment • Previous Articles     Next Articles

Spatiotemporal changes in vegetation greenness on the southern slopes of the Qilian Mountains and their responses to climate change and human activities

ZHANG Qian1,2(), CAO Guangchao1,2,3(), ZHANG Lele1,2, ZHAO Meiliang1,2   

  1. 1. Key Laboratory of Tibetan Plateau Land Surface Processes and Ecological Conservation, Ministry of Education, Qinghai Normal University, Xining 810008, Qinghai, China
    2. Qinghai Province Key Laboratory of Physical Geography and Environmental Process, College of Geographical Science, Qinghai Normal University, Xining 810008, Qinghai, China
    3. Academy of Plateau Science and Sustainability, People’s Government of Qinghai Province and Beijing Normal University, Xining 810008, Qinghai, China
  • Received:2024-04-21 Revised:2024-10-14 Online:2024-12-15 Published:2024-12-20
  • Contact: CAO Guangchao E-mail:18309740663@163.com;caoguangchao@qhnu.edu.cn

Abstract:

In this study, we investigated the spatiotemporal changes in vegetation greenness on the southern slopes of the Qilian Mountains and their responses to climate change and human activities. Utilizing the Google Earth Engine platform, we applied algorithms and remote sensing technologies to analyze these changes. By employing Sen’s trend analysis, the coefficient of variation, the Hurst index, ArcGIS spatial analysis, and multiple residual regression methods, we integrated multisource data products to comprehensively analyze the characteristics of vegetation greenness changes. Additionally, we assessed future trends and stability while thoroughly examining the influences of climate change and human activities. The results indicated the following: (1) From 2001 to 2020, vegetation greenness on the southern slope of the Qilian Mountains exhibited an overall upward trend, accompanied by significant spatial variations. Stability analysis revealed that the coefficient of variation ranged from 0 to 0.84, with a mean of 0.09, indicating that changes in vegetation greenness remained relatively stable and exhibited a positive trend. (2) Regarding influencing factors, both precipitation and temperature exhibited a positive correlation with vegetation greenness, with temperature showing a more pronounced effect. Notably, 95.7% of the study area passed the significance test, highlighting that temperature primarily drives changes in vegetation greenness. (3) Human activities have positively influenced changes in vegetation greenness. Overall, these changes result from the combined effects of climate change and human activities, with relative contribution rates of 36.68% for climate change and 63.32% for human activities. The higher contribution rate of human activities is closely linked to the implementation of ecological engineering initiatives.

Key words: vegetation greenness, spatiotemporal change, climate change, human activities, southern slopes of the Qilian Mountains