Long-Term Study of the Relationship Between Precipitation and Productivity in the Main Pasture Vegetation of a Steppe Ecosystem in Eastern Mongolia

Abstract

Long-term observations from 1982 to 2007 of aboveground biomass dynamics in three types of plant communities representative of the eastern Mongolian steppe are described. The dates of maximum green phytomass varied during the first year with the amount and period of precipitation and, in the second, in response to warmer conditions. A pattern to the change in 10-day accumulations of green phytomass was revealed. The accumulation process in all three communities was described by polynomial equations with high determination factors (0.98, 0.994, and 0.90, respectively). The amount of precipitation and air temperature did not immediately affect phytomass; rather, 20–30 days were required for precipitation, and 10–20 days for temperature, to have an effect. Seasonal performance of green phytomass was defined by the integral amount of precipitation and temperature for the vegetative period and was described by multivariate linear equations (R ² = 0.92, 0.79, and 0.87).