Response of vegetation to multi-timescales drought in the Qinling Mountains of China
Guizeng Qi, Jinxi Song, Qi Li, Hongying Bai, Haotian Sun, Shanhong Zhang, Dandong Cheng
Abstract
A deep understanding of the response characteristics of vegetation to drought is important for ecosystem and water resource management. In this study, we investigate spatiotemporal patterns of vegetation responses to droughts and their causes in the Qinling Mountains (QMs). The study showed that (1) there was a significant positive correlation (p < 0.05) between the Normalized Difference Degetation Index (NDVI) and Standardized Precipitation Evapotranspiration Index (SPEI) in 80.98% of the QMs. The most sensitive period of vegetation growth in response to drought was May-July. The average timescale of the vegetation response to drought changes was 11.88 months, where the vegetation response timescale on the northern slope (10.67 months) was shorter than that on the southern slope (12.02 months). (2) A clear relationship was identified between the vegetation response to drought and vegetation type and elevation, indicating that the overall vegetation sensitivity in the QMs is relatively high, with grasses being the most sensitive to drought conditions. Vegetation drought management should be focused on extremely sensitive and severely sensitive areas in aridified regions in the future.