米槠天然更新次生林皆伐地采伐剩余物叶分解及其化学组成变化  

Decomposition dynamics of leaf litter in logging residue of a secondary Castanopsis carlesii plantation and its chemical composition changes

作　　者：任卫岭 郭剑芬[1,2] 吴波波[1,2] 万菁娟 纪淑蓉 刘小飞[1,2] 

机构地区：[1]湿润亚热带山地生态国家重点实验室培育基地,福州350007 [2]福建师范大学地理科学学院,福州350007

出　　处：《应用生态学报》2015年第4期1077-1082,共6页Chinese Journal of Applied Ecology

基　　金：国家自然科学基金重点项目(31130013);国家自然科学基金面上项目(31370615)资助

摘　　要：对三明35年生米槠天然更新次生林皆伐地采伐剩余物叶的分解速率以及化学组成的年变化进行研究.结果表明:2012年5月至2013年4月,叶分解速率随时间呈指数变化趋势,干质量损失率>80%.K发生净释放,残留率<5%;N先累积后释放,P呈现先释放后累积再释放的趋势,N和P的残留率分别为19%和16%.养分释放速率以K最大,其次为P,N最小.木质素浓度在2012年5—10月呈先降低后上升再降低的趋势,从2012年11月至试验结束无明显变化,而在整个分解过程中纤维素浓度变化不显著.采伐剩余物叶分解过程中,N/P先上升后下降再上升,比值由18.6上升到21.1,木质素/N在分解前期波动较大,后期变幅较小.A field experiment was conducted to understand the decomposition rates and chemical composition changes of leaf litter in logging residues of a 35-year-old secondary Castanopsis carlesii plantation over a period of one year. Mass loss rate of leaf litter showed an exponential decrease with time from May 2012 to April 2013, with a total 80% loss of initial dry mass. Net potassium （K） re- lease was observed during this period, with only 5% of initial K remained. Nitrogen （N） featured a pattern of accumulation at the early stage and release later, while phosphorus （P） exhibited a se- quenee of release, accumulation, and release. The remaining of N and P were 19% and 16% of their initial mass, respectively. The release rate was highest for K and the lowest for N. Decomposi- tion of lignin indicated a trend of release-accumulation-release from May 2012 to October 2012, with no further significant change from November 2012 to the end of the experiment. The concentra- tion of cellulose nearly unchanged during the experiment. The N/P rate increased with decomposi- tion, ranging from 18.6 to 21.1. The lignin/N rate fluctuated greatly at the early stage and then al- most stabilized thereafter.

关 键 词：米槠次生林 皆伐 采伐剩余物 分解速率 化学组成 

分 类 号：S754.1[农业科学—森林经理学]