达日县高寒草甸土壤理化性质与物种多样性、地上生物量的关系

利用55个1m×1m的野外样方调查数据初步分析了达日县高寒草甸3种植被群落类型物种多样性与地上生物量及其同土壤理化性质的关系。结果表明:(1)土壤pH值和养分全量含量越低,其土壤有机质含量和速效养分含量越高。(2)在9个样地55个1m×1m的样方中共出现105种植物,物种丰富度最高为27种/m2,最低为4种/m2。(3)对于所有群落而言,物种多样性与地上生物量呈显著正相关关系,不同群落间,除矮嵩草群落外,小嵩草群落和山生柳+金露梅群落的物种丰富度与地上生物量呈显著正相关关系;对于Shannon-Wiener指数与地上生物量的关系,除山生柳+金露梅群落中两者呈显著正相关外,矮嵩草群落和小嵩草群落均没有表现出显著的相关性。(4)对于所有群落,土壤速效氮对物种多样性和地上生物量都有很大的影响,速效氮含量越高,物种多样性越丰富,地上生物量越高。

The soil physical-chemical properties of alpine meadow in relation to species diversity and aboveground biomass in Dari County

Based on the investigation of 55 sampling plots(1m×1m) in the field,this study provided an analysis of changes in species diversity and aboveground biomass among three vegetation types and relations of them to soil physicochemical properties in Dari County.The results showed that: First,Soil pH value and nutrient content was lower,the content of soil organic matter and available nutrient content both increased.Second,there appeared 105 plant species in the nine sample plots with 55 quadrate of 1m × 1m,in which the max species richness is 27 species/m2,the least is 4 species/m2.Third,for all communities,species diversity was significantly and positively correlated with aboveground biomass.For different communities: the species richness was positively correlated with aboveground biomass in both Kobresia pygmaea community and Potentilla fruticosal community;Shannon-Wiener index was only positively correlated with aboveground biomass in Potentilla fruticosal community.Fourth,For all communities,the soil available nitrogen had great influence on species diversity and the aboveground biomass to,which The higher available nitrogen content,the more abundant species diversity,and higher the aboveground biomass.