青藏高原北部高海拔地区嵩草草甸植物多样性分析

Plant Diversity of Alpine Kobresia Meadow in the Northern Region of the Tibetan Plateau

基于75个样条的野外调查资料,分析了青藏高原北部高海拔地区嵩草草甸的植物多样性.研究表明:α多样性指数从高山嵩草(Kobresiapygmaea)草甸、藏嵩草(\%K.tibetica)草甸到矮嵩草(K.humilis)草甸依次降低,而β多样性指数从高山嵩草草甸、矮嵩草草甸到藏嵩草草甸依次降低,同时,βws多样性指数趋于稳定的样方面积为8～16m2时.公路两侧迹地上次生恢复群落的α多样性均小于各自原生群落的α多样性,而恢复群落的β指数均大于原生群落的β指数.在冻土持续退化过程中,高寒草甸的α多样性指数和β多样性指数表现为先增加后降低的趋势.

Based on the survey in 75 zones, plant diversity of alpine Kobresia meadows is discussed in the northern region of the Tibetan Plateau. It is found that the α-diversity index of different grassland communities decreases gradually: Kobresia pygmaea meadow, K. tibetian meadow, K. humilis meadow, and that the α-diversity index of native communities is bigger than those of restorable communities. Again, the α-diversity index of aboveground communities first increases and then decreases in the degrading process of permafrost. The study also indicates that the β-diversity appears in steady state for sampling area of 8～16 m^(2), and the β-diversity index of different grassland communities decreases gradually: K. pygmaea meadow, K. humilis meadow, and K. tibetian meadow. In addition, the β-diversity index of native communities is bigger than those of restorable communities, and the β-diversity index of aboveground communities first increases and then decreases in the degrading process of permafrost.