青藏高原不同植被类型土壤微生物数量及影响因子

Quantity of Microbes in the Different Vegetation Types on the Qinghai-Tibetan Plateau

应用稀释平板法对青藏高原不同植被土壤0~25 cm土层的细菌、真菌和放线菌的数量特征进行对比研究。结果表明：植被类型、温度、土壤理化性质都影响微生物数量。不同植被类型下,微生物数量未达显著性差异,但是藏嵩草草甸和沼泽草甸的土壤微生物数量要大于其他植被类型。其中、灌丛草甸强烈的抑制细菌的生长,真菌对植被类型和温度最为敏感。不同植被下的土壤理化性质差异性显著,土壤理化性质与微生物数量显著相关,较适的土壤全氮（6.96～15.72 g kg-1）、磷和土壤有机质（302.41~367.79 g kg-1）促进土壤微生物的生长;高含量的磷不利于真菌、细菌和放线菌的生长。

Quantity of bacteria, fungi and actinomycetes were studied at different vegetations types by the way of pour plate method on the Qinghai-Tibetan Plateau. The results showed that vegetation type, temperature, soil physics and chemicals affected quantity of soil microbes. But there was not significant difference between quantity of microbes and vegetation types. However, quantities of microbes in the swamp meadow and Kobresia tibetica meadow were larger than those in other types. Alpine shrub meadow restrained bacteria strongly. Besides, fungi were most sensitive to vegetation types and temperature. What was more, there were significant differences of soil chemical and physical properties at different vegetation types. So suitable soil total N, P and organic matter were benefit for growth of microbes. In the research zone, the suitable soil total N and organic matter were 6.96 - 15.72 g kg^-1 and 302.41 - 367.79 g ^-1, respectively. What was more, total Phosphorus enrichment in soil environment led to the inhibition of soil microbes.