The spatial-temporal patterns of spring phenology in the temperate grasslands of China and their response mechanisms to climatic factors

Understanding spring phenology dynamics in China's temperate grasslands is crucial for carbon cycle predictions. Using GIMMS NDVI data (1982–2014), we analyze SOS trends, considering climate variables. SOS advanced by 0.6 days/decade, with diverse trends across grassland types. TM advanced significantly (2.1 days/decade), TS and TDS showed non-significant changes. SOS correlates positively with temperature and radiation, negatively with precipitation and SPEI. Precipitation's impact is greatest (35%), followed by SPEI (30%), radiation (18%), and temperature (17%). Precipitation's significance increases in arid regions. These findings are vital for climate adaptation in arid and semi-arid ecosystems.