鼎湖山3种不同林型下的土壤酸度和养分含量差异及其季节动态变化特性

主要研究了鼎湖山自然保护区内３种主要林型（季风常绿阔叶林、马尾松针阔叶混交林、马尾松林）下０－６０ｃｍ土层的酸度，有机质、水解氮、速效磷、钾、交换怀钙、镁等几各营养元素的含量状态以及它们的季节动态变化。结果表明，土壤ＰＨ值都胡着季节变化而逐渐升高，不同林型间的差异是松林〉混交林〉阔叶林，而且它们都是表层低于中下层，产生上述现象的原因可能是由于植被类型不同导致土壤微生物数量不同的结果，土壤养分含量明

THE SOIL ACIDITY AND NUTRIENT CONTENTS, AND THEIR CHARACTERISTICS OF SEASONAL DYNAMIC CHANGES UNDER 3 DIFFERENT FORESTS OF DINGHUSHAN NATURE RESERVE

The soil acidity and contents of several nutrients,organic matter,hydrolysable N,available P,K,exchangeable Ca,Mg,and their seasonal dynamic changes under 3 different forests, Pinus massoniana forest(PMF),pine and broadleaf mixed forest(PBMF),and monsoon evergreen broadleaf forest(MEBF) of Dinghushan Nature Reserve were investigated.Soil pH was ranked in the order PMF>PBMF>MEBF,and increased with soil depth and the seasonal changes.The reason for the above phenomena was probably soil microbes,which had a significant correlation with soil pH.Soil nutrients were the highest in MEBF, second in PBFM,and lowest in PMF.In the same soil profile,they were the highest in the surface horizon,and decreased with depth except exchangeable Ca.The seasonal changes affected significantly available P,but did slightly organic matter.