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

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.