Response of NDVI and SIF to Meteorological Drought in the Yellow River Basin from 2001 to 2020

Understanding the response of vegetation to drought is great significance biodiversity protection terrestrial ecosystem. Based on MOD13A2 NDVI, GOSIF, and SPEI data Yellow River Basin from 2001 2020, this paper used methods Theil–Sen median trend analysis, Mann–Kendall test, Pearson correlation analysis analyze whether change trends monitored by MODIS GOSIF are consistent their sensitivity meteorological drought. The results showed that NDVI SIF increased significantly (p < 0.001) at rate 0.496 × 10−2 0.345 10−2, respectively. significant improvement area (66.49%, p 0.05) higher than (50.7%, 0.05), spatial distribution growth consistent. negative value SPEI-12 accounts for 65.83%, with obvious periodic changes. positive areas SIF-SPEI in spring, summer, autumn (R > 0, were 7.00%, 28.49%, 2.28% respectively, which NDVI-SPEI (spring: 1.79%; summer: 20.72%; autumn: 1.13%). responded more strongly farmland was correlated (0.3424, 0.01). indicate responsive NDVI. Analyzing can provide constructive reference ecological protection.