亚热带-暖温带过渡区不同林型土壤理化性质及土壤微生物量分析

Analysis on differences of soil physical and chemical properties and microbial biomass of different forest types in subtropical-warm temperate climate transition region

为应对人工林退化及其经营管理问题,探究不同林型(针叶林、阔叶林、针阔混交林)在不同土壤深度下(落叶层、半分解层、腐殖质层和矿化层)土壤理化性质以及微生物量碳氮含量的特征,旨在为当地人工林的经营管理提供理论依据.结果表明:在落叶层针叶林和阔叶林的全碳含量显著高于针阔混交林,而全氮含量则无显著差异;在半分解层中阔叶林的全碳、全氮含量均低于针叶林和混交林;在腐殖质层和矿化层混交林的全碳全氮含量均显著低于纯林.在不同土层中全磷含量呈现出倒“V”型趋势,整体来看阔叶林和针阔混交林中的全磷含量显著高于针叶林;土壤中铵态氮、硝态氮和土壤微生物生物量碳在土壤各层的林型间均无显著差异;而土壤微生物生物量氮含量在腐殖质层表现为在纯林中显著高于混交林.从土壤理化性质和土壤微生物特性方面来看,该地区种植马尾松纯林可能更有利于土壤表层养分的积累.

In order to deal with the problems of plantation degradation and management,the characteristics of soil physical and chemical properties and microbial biomass carbon and nitrogen content of different forest types(coniferous forest,broad-leaved forest,coniferous-broad-leaved mixed forest)under different soil depths(deciduous layer,semi-decomposition layer,humus layer and mineralized layer)were studied,in order to provide theoretical basis for the management of local plantation.The results showed that the total carbon content of coniferous forest and broad-leaved forest in deciduous layer was significantly higher than that of mixed coniferous and broad-leaved forest,while the total nitrogen and total phosphorus showed opposite results;In semi-decomposition layer,the total carbon content of coniferous forest and mixed coniferous and broad-leaved forest was significantly higher than that of broad-leaved forest,while the total nitrogen content was the highest in mixed coniferous and broad-leaved forest,and the total phosphorus content of broad-leaved forest and mixed coniferous and broad-leaved forest was significantly higher than that of coniferous forst;In humus layer,the contents of total carbon,total nitrogen and microbial biomass nitrogen in coniferous forest and broad-leaved forest were significantly higher than those in coniferous and broad-leaved mixed forest;In mineralized layer,the contents of total carbon,total nitrogen and total phosphorus in coniferous forest and broad-leaved forest were significantly higher than those in coniferous and broad-leaved mixed forest.From the aspects of soil physical and chemical properties and soil microbial biomass characteristics,in the litter layer and semi decomposition layer,coniferous and broad-leaved mixed forest is more conducive to the accumulation of soil carbon,nitrogen and phosphorus,while in the humus layer and mineralization layer,pure forest is more conducive to the accumulation of soil nutrients.Therefore,planting coniferous and broad-leaved mixed forest in this area may be more conducive to the accumulation of soil surface nutrients.