青海省天然草地类型空间分布特征及气候分区

根据青藏高原气候带划分的水分和热量指标，得到符合青海高原气候带划分的修正指标，随着近半个世纪以来青藏高原的气候变暖效应，青海高原亚寒带和温带的最热月上限温度指标增加了1～2 ℃，高原寒带≥0 ℃年积温上限值增加50 ℃。结合青海省干湿分布状况，把青海省分为6个气候区域，按照草地类型的划分原则、系统与标准，把青海省10个草地类型进行组合分类划分至6个气候区域；阐述了不同草地类型的分布与海拔、温度及降水等生境特征的关系；定量评价了各草地类型的丰富度、生物量、草层高度以及草群盖度等植被特征。

Characteristic of spatial distribution and climate zone of natural grassland types in Qinghai

Based on the indexes of moisture and heat of Qinghai Tibetan Plateau, the appropriate modified indexes were established. It was found that because of the climatic warming effect on Qinghai Tibetan Plateau in recent half century, the upper limit temperature index in the hottest month of sub frigid zone and temperate zone on Qinghai Tibetan Plateau increased 1 to 2 ℃; the lower limit of accumulative temperature (≥0 ℃) increased 50 ℃. According to the moisture status in Qinghai, 6 climatic zones were setup; meanwhile, 10 grassland types were grouped and fitted to these 6 zones. The relationship between grassland distribution and habitat characteristics (altitude, temperature and precipitation) was described. And the richness, biomass, height and coverage of grassland community were evaluated as well.