重庆北部水源区水源涵养林构建模式对土壤养分的影响

Effects of Structure Models of Water Conservation Forest on Soil Nutrients in Northern Water Source Area of Chongqing

为探讨不同模式水源涵养林与土壤肥力的关系,以便从营林的角度探讨如何合理利用土壤,以最大限度保持土壤肥力和发挥森林的水源涵养功能,提高水源涵养林对重庆市水源区的水源涵养效益。对重庆北部水源区6种不同构建模式的水源涵养林地土壤有机质、活性酸(pH)、全氮、全磷、全钾、速效氮、速效磷、速效钾和土壤阳离子交换量(CEC)进行了分析,并用主成分分析方法对土壤肥力状况进行了综合评价。结果表明:构建模式对土壤养分特征具有显著的影响作用,各模式林地土壤养分特征差异显著,不同层次土壤有机质含量、pH、CEC、全P、全N、速效P、速效N、速效K存在极显著或显著差异,不同层次土壤全K含量间差异不显著;土壤有机质含量、CEC、全P、全N随土壤深度按照幂函数递减,土壤速效P、速效N、速效K深度按照指数函数递减,土壤活性酸(pH)与土壤层次之间无明显相关性。土壤肥力由高到低依次为:广东山胡椒×杉木混交林地>马尾松火烧迹地>楠竹×四川山矾×马尾松混交林地>马尾松×广东山胡椒混交林地>楠竹纯林>四川大头茶×四川山矾混交林地。广东山胡椒×杉木混交组合模式对于提高土壤养分含量,改善土壤状况具有明显效果。

To explore the relationship between soil nutrients and different models of water conservation forest in order to find the best ways to use soil rationally from the perspective of forests and maintain soil nutrients in the maximum and play a functional to water conservation forests. To improve water efficiency of water conservation of water conservation forest to water source area of Chongqing. The soil nutrients of 6 structure models of water conservation forest in northern water source area of Chongqing was evaluated in terms of soil organic matter, active acid （pH）, total N, total P, total K, available N, available P, available K and soil cation exchange capacity （CEC） and total porosity by the method of principal component analysis. It has been proposed that there were significant effects of structure models of water conservation forest on soil nutrients. It is very significant or significant difference on soil organic matter content, pH, CEC, total P, total N, available P, available N, available K of different soil levels. However, it is not significant to total K content in the different soil levels. Soil organic matter content, CEC, all-P, all-N with soil depth in accordance with the power function decline and soil available P, available N, available K in accordance with the exponential function depth reduced. Activity acid soil （pH） and soil was no significant correlation between the soil level, soil fertility by descending as follows. Lindera kwangtungensis×Cunninghamia lanceolata forests〉Pinus rnassoniana×Cryptomeria f ortunei forests〉Ph yllostach ys pubescens×Symplocos setchuanensis×Pinus massoniana forests×Pinus massoniana×Lindera kwangtungensis forests×Ph yllostach ys pubescens forests×Gordonia acuminata×Symplocos setchuanensis forests. Lindera kwangtungensis×Cunninghamia lanceolata forests for improving soil nutrients and soil conditions had played an important role.