Alpine grassland soil moisture variation characteristics and its relationship with climate factors in Three River Source

The data supporting this study were collected during 1999-2016 from the pastureland weather station of Xinghai County, Qinghai Province, at the Three River Source. They included soil moisture content and herbage growth period. We analyzed the changes of alpine meadow soil moisture characteristics, the soil moisture change characteristics at different stages, and their relationship with the herbage growth period. The results showed that the soil moisture content in each layer increased from 0-50 cm in the alpine grassland, the soil moisture was significantly increased trend of each layer in spring 0 to 40 cm, the soil moisture increase rate decrease with the increase of soil depth. Soil moisture content during growing seasons increased significantly from 1999-2016, and it correlated significantly with precipitations during the growing seasons. At the flowering stages, soil moisture content was significantly positively correlated with atmospheric temperature. Moreover, at the heading stages and throughout the whole growing season, they were significantly negatively correlated with atmospheric temperatures. The increase of soil moisture content in alpine meadow growth season is beneficial for grassland vegetation growth.