我国沙拐枣属(Calligonum L.)天然群落物种多样性与土壤因子的耦合关系

对我国沙拐枣属(Calligonum L.)天然群落15个物种所形成的群落多样性指数和土壤指标进行回归分析。结果表明,颗粒度组成、土壤酸碱度、有效P、K 、Na 、HCO3-、Cl-与物种多样性指数有显著相关关系(P<0.05)。粗砂粒(0.5~0.25 mm)、土壤酸碱度、有效P和K 与物种多样性指数的最好拟合为二项式,即高或低的物种多样性出现在梯度中间位置;细砂粒(0.1~0.05mm)和Cl-与物种多样性的关系表现较为复杂,包括线性和二项式关系;Na 和HCO3-分别与物种多样性指数表现为显著线性负相关和正相关关系,表明Na 含量越多,物种多样性越小,HCO3-含量越多,物种多样性则越高。年降雨量仅与均匀度指数拟合为二项式,而与其他指数的关系表现不显著,年均温与物种多样性指数拟合较好的为二项式,仅与丰富度指数以及均匀度指数表现出显著负相关与正相关。

Coupling relationship between Calligonum L. community species diversity and soil factors in China

Regression analysis was used to study the relationship between Calligonum L.community species diversity and soil factors.The results show that the particle sizes,soil pH,available P,K ,Na ,HCO3-and Cl-are correlative to species diversity indices significantly(P<0.05).By analyzing thick sand(0.5-0.25 mm,soil pH,available P and K mattered with species diversity indices respectively,it is proved that they are all fitted in form of binomial model,which means that the highest or lowest species diversity occurs in the middle of the gradient.The relationships between silver sand(0.1-0.05 mm) and species diversity indices,Cl-and species diversity indices are complicated,furthermore both of them are fitted in form of binomial model and linear regression.The relationship between Na and species diversity indices is negative linear,while the reverse conclusion on the relationship between HCO3-and species diversity has been reached.Regression analysis also indicates the relationship between annual precipitation and species evenness index is fitted best in form of binomial model,and the relationship between annual mean temperature and species diversity indices is fitted best in form of binomial model or linear regression.