短期氮磷添加对晋北赖草草地植物群落特征的影响

Effects of short-term N and P addition on plant community characteristics of Leymus secalinus grassland innorthern Shanxi Province

摘要:

以晋北赖草(Leymus secalinus)草地为对象,通过添加氮、磷分析草地群落植物多样性与生产力,研究养分添加对草地群落植物组分、结构和多样性格局的影响。结果表明:短期氮、磷添加对草地群落Shannon-Wiener多样性指数、Pielou均匀度指数和Margalef丰富度指数均无显著影响。单独添加氮、磷对草地群落生产力的影响较小,同时添加氮、磷通过增加杂类草在草地群落中的比例,可增加草地地上生物量,显著降低植物群落根冠比。赖草草地群落多样性与生产力之间呈显著正相关关系。

Abstract:

In order to study the effects of nutrient addition on plant composition,structure and diversity pat-tern of Leymus Secalinus grassland in northern Shanxi Province,the plant diversity and productivity of grassland community were analyzed by adding nitrogen and phosphorus.The results showed that the Shannon-Wiener diversity index,Pielou evenness index and Margalef richness index were not significantly affected by short-term N and P addition.The results also implied that the effects of addition of N and P alone on grassland productivity were insignificant,whereas,addition of N and P at the same time increased the aboveground biomass,and significantly reduced the root shoot ratio of plant community by increasing the proportion of forb in grassland community.There was a significant positive correlation between community diversity and productivity of Leymus Seca-linus grassland.