The relations of natural grassland vegetation growth and climate conditions in Xinghai of Qinghai Province

To understand the relationship between natural grassland vegetation growth and meteorological conditions in Xinghai, Qinghai Province, the present study was based on 11 meteorological and grass observation materials that analyzed the relationship of turning green, growth height, yield characteristics, and hydrothermal factors systematically. The results showed that the turning green period for grass during the spring rain was 38 d greater than during the spring drought years. The grass turning green period was in advance or delay, which related with the time of ≥0 ℃, the rainfall of March to April of the measured year and rainfall of September to November of the previous year during 2005-2015. In addition, precipitation was the best climate model to obtain a linear regression equation for the period of the grass turning green. Grass height growth amounts were positively correlated to precipitation during all stages; however, were negatively correlated to temperature. Moreover, precipitation increased 610 mm during the forage growth stage, and new herbage yields added 225 kg per hectare. Thus, precipitation was a major meteorological factor that limited the period of grass turning green, and its growth and development.