Increasing control of climate warming on the greening of alpine pastures in central Asia

International Journal of Applied Earth Observations and Geoinformation

Yaning Chen¹  Jianhua Xu²  Zilong Xia²  Dahui Li³  Lilin Zheng³  Debin Lu⁴  Guoyu Xu⁵ 

[1] Corresponding author at: Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, Shanghai 200241, China.;Research Center for East-West Cooperation in China, East China Normal University, Shanghai 200241, China;Key Laboratory of Geographic Information Science (Ministry of Education), School of Geographic Sciences, East China Normal University, Shanghai 200241, China;School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, Jiangsu Province 210023, China;School of Geospatial Engineering and Science, Sun Yat-Sen University, Zhuhai, Guangdong 519082, China;

关键词: Normalized Difference Vegetation Index;    Remote sensing data;    Alpine pastures;    Climate warming;   

DOI  :  

来源: DOAJ

【 摘 要 】

High-altitude environments are among the most sensitive to climate change, where impacts are amplified. To clarify alpine pasture dynamics in three typical mountains (i.e., Altay, Tianshan, and Kunlun) in central Asia, the change trends in the long-term summer peak Normalized Difference Vegetation Index (NDVI) were examined by applying three satellite sources: Landsat ETM+/OLI (1999–2020), Global Inventory Modeling and Mapping Studies (1981–2013), and Moderate Resolution Imaging Spectroradiometer (2000–2020). Satellite-derived NDVIs are reliable because similar variations can be observed during overlapping periods. The results show that the alpine pastures experienced overall greening. The most significant greening was observed in Kunlun Mountains and the high-altitude areas of Tianshan and Altay Mountains, where the annual average temperature is lower. Relationships between NDVI and potential driving factors, such as average precipitation (AP), surface soil water content (SSWC), total water storage (TWS), snow cover frequency, growing degree days (GDD), and average temperature (AT), were further analyzed. Over the last two decades, the optimal habitat of alpine pastures became warmer and wetter, as the AT, GDD, SSWC, TWS all showed increased trends. However, AP decreased at a rate of –0.625 mm/year, indicating that melting ice materials under current warming helped preserve moisture and soil water availability for pasture growth. Additionally, the primary factor regulating greenness patterns shifted from AP during 2002–2011 to GDD during 2012, 2014, and 2016–2020, indicating that the alpine pastures in central Asia have been increasingly dependent on climate warming. Our study highlights that the response of alpine pastures to climatic factors might change under ongoing climate change.

【 授权许可】

Unknown