关键词: 草原学, 模拟增温, 矮嵩草草甸, 暖室, 群落结构

Abstract: A mimic 5-year temperature increased in a greenhouse raised the soil temperature of 10 and 20 cm depth 1.86℃ higher than that in the open, the 10 and 20 cm above ground air temperature 1.15℃ higher, and the soil surface temperature 1.87℃ higher than that in the open respectively, The extent of temperature increase was generally greater in the early plant growing season than in the later stage and the plant withering period.The result showed that in the first few years of the 5-year experiment, the yearly biomass from the greenhouse is weightier than that of the control in the open.However, after the 5-year period,the yearly biomass form the greenhouse decreased and became less than of the control. Though higher temperature increased the number of grass species, prevented weeds from teeming the land,and apparently extended the plant growing period,and raised the biomass,the heat accelerated the growth and maturing of plants, thus shortening the growing period actually.Moreover, the glass of the greenhouse retarded the fluctuation of temperature of daytime and the night time,and restricted the accumulation of dry matter.all this leads to the decrease of biomass in the greenhouse.The micro-climatic change of soil structure which also changes the structure of the plant species and leads to the species succession process.Consequently,global warming not only affects the plant productivity,but the succession of plant types as well.

Key words: Grassland science, Mimic air temperature increase, kobresia humilis meadow, Greenhouse, Community structure