作　　者： ; ; ; ;

机构地区： 中国科学院华南植物园

出　　处： 《植物生态学报》 2011年第7期699-706,共8页

摘　　要： 运用分解袋法研究了不同布置时间的凋落物在亚热带森林分解的初期过程,探讨了不同布置时间的凋落物经过相同时间分解的差异及环境因子对其分解速率特别是分解速率常数k的影响。结果表明:在凋落物分解较快的鼎湖山季风常绿阔叶林,不同时间布置的凋落物经过12个月的分解,其残留率及k均存在较大的差异。不同布置时间的凋落物的分解率在前期(0–6个月)与其相应阶段的环境因子呈显著相关关系,但与后期的环境因子相关性并不显著。不同布置时间的k值的变化范围为0.78–1.30,起始于雨季的k值较大,起始于旱季的较小(p<0.001),其大小与分解前期的环境因子相关性较高,与整个分解过程中的环境因子相关性较低。因此,凋落物的凋落时间可能影响其分解速率;由于布置时间不同而导致k值估算的不准确将对森林生态系统的养分循环及其碳平衡的评估产生很大影响。 Aims Estimation of ecosystem carbon balance may be affected by timing of sampling. Our objective was to de-termine the effect of different incubation starting times on litter decomposition rate （k） in a tropical and subtropi-cal forest. Methods We used litter bags and incubated them in the field at the same site beginning on eight different start-ing times over a year, beginning January 13 and at 45-day intervals. Each of the eight sets of litter bags was sam-pled four times over a period of 12 months, remaining litter mass was determined and k values were estimated. Temperature, precipitation, photosynthetically available radiation, soil water content and relative humidity were measured throughout the experiment. Important findings The remaining litter mass and k values were significantly different （p 0.05） among the eight starting times. Rate of litter decomposition was significantly （p 0.05） correlated to temperature and pre-cipitation during the early phase rather than the later phase of the experiment. The k values ranged from 0.78 to 1.30, and were significantly higher （p 0.001） for litter whose incubation started in the wet seasons as compared to the dry seasons. Therefore, time for the start of incubation may significantly influence estimation of k values, which in turn may influence estimation of ecosystem carbon balance.

关 键 词： 环境因子 布置时间 凋落物分解速率常数 凋落物分解 亚热带森林

领　　域： [农业科学]