天然林人工更新后枯落物对土壤微生物数量及有效养分含量的影响  

Effects of Litter on Soil Microbe Counts and Available Nutrients Content in Soils of Natural Forest after Artificial Regeneration

作　　者：王景燕[1] 胡庭兴[1] 龚伟[1] 宫渊波[1] 罗承德[1] 

机构地区：[1]四川农业大学林业生态工程省级重点实验室,四川雅安625014

出　　处：《四川农业大学学报》2010年第3期285-290,共6页Journal of Sichuan Agricultural University

基　　金：国家"十五"科技攻关项目(2004BA606A-06);国家"十一五"科技支撑计划项目(2006BAC01A11);四川省教育厅项目(08ZB038);四川农业大学211工程创新团队项目"长江上游植被恢复与重建"

摘　　要：天然常绿阔叶林及其人工更新成檫木林、柳杉林后0-20 cm土层土壤在25℃、自然含水量培养环境下,添加不同枯落物处理,培养15、30、45、60、75和90 d后,分别测定土壤细菌、真菌、放线菌数量及碱解氮、有效磷和速效钾含量。结果表明：在不添加枯落物处理中,土壤细菌数量在初期持续增加至45 d达到最大值,随后不断下降;在添加枯落物处理中,细菌数量在60 d达到最大值,各处理真菌和放线菌数量分别在60 d和45 d达到最大值。土壤有效养分含量均随培养时间延长而增加。各培养时间土壤微生物数量和有效养分含量,在不添加枯落物时均为天然常绿阔叶林〉檫木林〉柳杉林,各林分土壤添加其自身林地枯落物高于不添加枯落物,而且在檫木林、柳杉林土壤中添加天然常绿阔叶林枯落物比添加其自身林地枯落物高。土壤微生物数量和有效养分含量两者间具有较好的相关性。说明天然常绿阔叶林人工更新后土壤微生物数量和有效养分含量下降,枯落物组成与质量对土壤肥力具有重要影响。Soil bacteria,fungi and actinomycetes counts,and hydrolysis N,available P and K contents in soils were determined to understand the effects of litter on soils in natural evergreen broadleaved forest,Sassafras tzumu plantation and Cryptomeria fortunei plantation.Soils were collected in the 0~20 cm layer and incubated for 15,30,45,60,75 and 90 days in the laboratory with the temperature of 25 ℃,natural water content and different litters.The results indicated that microbial counts increased with incubation time before reached the max values,and then decreased with incubation time after reached the max values.Bacteria counts reached the max value in 45 and 60 days of incubation time in soils with and without forest litter addition,respectively;fungi and actinomycetes counts reached the max value in 60 and 45 days incubation,respectively.Available nutrients content in soil increased continuously with the extension of incubation time.Microbial counts and available nutrients content in soils showed the ranked order of natural evergreen broadleaved forest Sassafras tzumu plantation Cryptomeria fortunei plantation when the forest litter was not added to the soil.The added forest litter increased the microbial counts and available nutrients content in soils regardless of the forests.Adding the litter from the natural evergreen broadleaved forest to soils of the Sassafras tzumu plantation and Cryptomeria fortunei plantation led to higher microbial counts and available nutrients content,in contrast with adding the litter from the Sassafras tzumu plantation and Cryptomeria fortunei plantation,respectively.Significant correlation existed between soil microbial counts and available nutrients content.The results suggested that the artificial regeneration of the natural evergreen broadleaved forest into the Sassafras tzumu plantation and Cryptomeria fortunei plantation might lead to the decrease of soil microbial counts and available nutrients content;in addition,the composition and quality of forest litter have important effe

关 键 词：天然常绿阔叶林 人工更新 枯落物 微生物 养分 

分 类 号：S154.36[农业科学—土壤学] S714.3[农业科学—农业基础科学]