【摘要】 为了认识不同水土保持林及其配置模式对土壤养分的保护效应,以重庆四面山低山丘陵区水土保持林为研究对象,研究了不同水土保持林不同时期的土壤养分含量。该文对土壤养分含量先后进行了描述性统计分析、相关性分析和主成分分析,最后利用主成分分析提起的两个养分综合指标进行方差分析。结果表明:空旷地、人工林及天然林土壤养分含量差异显著,其中天然林土壤养分含量最高,其次是人工林。天然林和人工林土壤有机质、全N、有效P和速效K含量分别为:82.61 g/kg、2.81 g/kg、8.86 mg/kg、120.91 mg/kg和59.80 g/kg、2.14 g/kg、8.43 mg/kg、98.81 mg/kg。与空旷地土壤养分含量相比,分别同比增加了231.08%,212.06%,11.77%,84.39%和139.67%,138.12%,6.32%,50.69%。10 a生与5 a生人工林土壤第一主成分养分含量差异显著,其中前者第一主成分养分含量比后者增加了127.59%。它们的土壤有机质、全N、有效P及速效K平均含量与空旷地相比,分别同比增加了202.47%,265.01%,10.06%,76.22%和125.12%,75.39%,3.46%,42.14%。10 a生人工林对土壤养分的保护结果达到了天然次生林的水平。在本研究中,不同配置模式的水土保持林,对土壤养分影响差异不显著。更多还原

【Abstract】 In order to understand the protection effect of different forests for soil and water conservation and their configuration patterns on soil nutrients,soil nutrients of these forests in the district of low mountains and hills in Simian Mountain of Chongqing were studied in different periods by applying descriptive statistical analysis,correlation analysis,principal component analysis and analysis of variance.The results showed that: ①There were significant differences of soil nutrients among bare land,plantations and natural forests,with the order of natural forests > plantations for soil and water conservation > bare land.In natural forest and plantation sample plots,the organic matter content,total N,available P and readily available K concentration was 82.61 g/kg,2.81 g/kg,8.86 mg/kg,120.91 mg/kg,59.80 g/kg,2.14 g/kg,8.43 mg/kg,98.81 mg/kg respectively,which increased by 231.08%,212.06%,11.77%,84.39% and 139.67%,138.12%,6.32%,50.69% accordingly when compared with those in bare land.② A significant effect of forest age on soil nutrients was found.Compared with 5-year-old plantations,the nutrients concentrations in the first principal component in the 10-year-old plantations increased 127.59%.When compared with the bare land,the organic matter content,total N,available P and readily available K concentration in the 10-year-old plantations and 5-year-old plantations increased 202.47%,265.01%,10.06%,76.22% and 125.12%,75.39%,3.46%,42.14% respectively.③The 10-year-old plantations were the rival of the natural forests for soil nutrients protection.However,there were no significant differences between different configuration patterns of forests for soil and water conservation on soil nutrients.更多还原