高寒草甸不同退化程度土壤微生物数量变化及影响因子

应用稀释平板法对青藏高原不同退化程度高寒草甸土壤0~30 cm土层的细菌、真菌和放线菌数量特征进行对比分析。结果表明,随着高寒嵩草草甸退化程度的加剧,地下生物量、生物量、优良牧草生物量、土壤有机质、全氮及全磷都显著降低(P<0.05),土壤微生物数量随之大幅度减少,尤其是真菌数量显著降低(P<0.05)。植被地下生物量、土壤有机质及全氮与土壤微生物数量显著正相关(P<0.05)。植被地下生物量、优良牧草生物量、有机质、全氮与真菌数量呈显著正相关(P<0.05);海拔和裸地面积与真菌数量呈显著负相关(P<0.05)。

Changes of Microbes Population in the Different Degraded Alpine Meadows on the Qinghai Tibetan Plateau

Quantity of bacteria,fungi and actinomycetes were studied at different degraded Alpine Meadow by the way of pour plate method on the Qinghai-Tibetan Plateau.The results showed that microbes population,especially fungi population sharply decreased because belowground-biomass,aboveground-biomass,soil organic matter,total-N,total-P decreased significantly(P<0.05).Obviously,belowground biomass was positively correlated to microbes population(P<0.05) just as soil organic matter and microbes population.Moreover,there was significant correlation between total-N and microbes population.What was more,biomass,dominated biomass,soil organic matter and total-N had significant negatively correlated to fungi population(P<0.05).In contrast,altitude,bared area had significant negative correlation with fungi population(P<0.05).