渝北不同模式水源涵养林植物多样性及其与土壤特征的关系

以重庆缙云山8种不同构建模式的水源涵养林及林地土壤为研究对象,用物种多样性指数(simpson指数、Shannon-Wiener指数)、均匀度指数(Pieiou指数)和物种丰富度指数(Margalef指数)以及用土壤容重、毛管孔隙度、非毛管孔隙度、pH值、有机质、全氮、全磷、全钾、速效氮、有效磷、速效钾和阳离子交换量12个指标表征土壤的物理性状和养分特征,分析了8种群落的植物多样性、土壤特征及二者的相互关系.结果表明:物种多样性以广东山胡椒(Lindera kwangtungensis)×杉木((7unninghamia anceolata)混交林最高.马尾松(Pinus massoniana)×广东山胡椒混交林次之,马尾松×柳杉(Cryptomeria fortunei Hooibrenk)混交林和毛竹(Phyllostachys pubescens)纯林最低.各模式林地土壤特征差异显著,以毛竹纯林土壤质量最差.在该地区针阔混交林对提高物种多样性和改良土壤作用显著,针叶林及纯林则较差.物种多样性指数与土壤特征因子的相关性分析表明,不同模式水源林群落植物多样性与土壤特征因子存在一定相关性,其中与土壤物理性状特征关系不显著,与养分特征关系显著.全N与全K与四个多样性指数呈显著或极显著的正相关,Shannon-Wiener指数、Simpson指数和有机质、阳离子交换量、速效P呈显著的正相关,特别是有机质和全N两因子与物种多样性关系最密切.

Plant biodiversity of different water conservation forest models and their relationship with soil properties in northern water source area of Chongqing city, southwestern China

In Jinyun Mountain, Chongqing city, water conservation forest and woodland soil of eight forest models were taken as study objects. Plant biodiversity of water conservation forest models and their relationship with soil properties were studied. The species diversity of eight forest communities were expressed with diversity index(Shannon-Wiener index, Simpson index), evenness index(Pielou index) and richness index(Margalef index). Twelve soil indicators were selected to describe soil physical properties and nutrient characteristics, including soil bulk density, capillary pore, non-capillary pore, organic matter, active acid(pH), total N, total P, total K, available N, available P, available K and soil cation exchange capacity(CEC). The results showed that the species diversity of Lindera kwanglungensis×Cunninghamia anceolata mixed forest was the highest, followed by Pinus masson-ianax-Lindera kwangtungensis mixed forest, and Phyllostachys pubescens forest was the worst. There are significant difference of soil characteristics in each forest model forest. The soil quality of Phyllostachys pubescens pure forest was the poorest. Coni-fer-broadleaved mixed forest play a significant role in improving species diversity and soil quality, however, the effect of coniferous forest and pure forest was poor. Correlation analysis of species diversity index and soil characteristics factor showed that plant diversity indices of different water conservation forest modes related to soil characteristics of communities, significantly to soil nutrient characteristics, but not obvious to soil physical properties characteristics. Total N and total K have significant or quite significant positive correlation to all four full-diversity indices. Organic matter, CEC and available P significant positively correlated to Shannon-Wiener index and Simpson index. Organic matter and total N, had the closest relationship with species diversity.