凋落物分解研究综述  

A Review on Litter Decomposition

作　　者：王相娥[1] 薛立[1] 谢腾芳[1] 

机构地区：[1]华南农业大学林学院,广东广州510642

出　　处：《土壤通报》2009年第6期1473-1478,共6页Chinese Journal of Soil Science

基　　金：广东省林业局项目(4400-F07041;4400-F06051)资助

摘　　要：综述了森林凋落物分解的研究方法、分解过程和影响因子。凋落物分解的研究方法有凋落物网袋法、小容器法、15N和14C法,其中网袋法是最常用的凋落物分解的研究方法。凋落物分解的过程可分为三个阶段:粉碎、物理淋溶过程和有机物的分解代谢过程。凋落物分解过程中的养分迁移出现3种模式:淋溶—释放模式、淋溶—富集—释放模式和富集—释放模式。气候影响凋落物的分解速率,其中温度和湿度被认为是影响凋落物分解主要的气候因子。全球变暖、CO2浓度升高、降水状况的变化影响着凋落物分解。不同植物的凋落物的化学组成不同,从而影响它们的分解率。常见的凋落物分解指标有C/N比、木质素/N比、N及P的初始浓度等。凋落物中C/N比越高、N的含量愈低、木质素含量高,凋落物分解速率越慢。土壤动物和微生物对凋落物分解有重要作用。CO2浓度升高可以通过改变植物凋落物的基本性质和改变土壤湿度及潜在地改变生态系统分解者群落而间接影响凋落物分解。N沉降可通过改变凋落物的N含量而影响凋落物的分解速率。Litter decomposition measurement, its decomposition course and the factors controlling its decomposition rate were summarized. Litter measurement includes litter-bag method, mini-container method and 15N and 14C techniques, and the litter-bag method is the most common method for the litter decomposition measurement. The decomposition course of litter includes it＇s broking down, nutrient release through leaching and decomposition. The course of nutrient dynamics during decomposition often can occur in three methods： 1） nutrient release through leaching and nutrient release from the litter; 2） nutrient release through leaching, a net immobilization of nutrients and nutrient release from the litter;3） a net immobilization of nutrients and nutrient release from the litter. Climate including global warming, elevated CO2 atmospheric concentration and change in precipitation affects litter decomposition, and temperature and moisture are the most important factors controlling the litter decomposition among them. The chemistry compositions of litters are different from plant species, which affects their decomposition rates. C/N and lignin/N and N and P concentrations are considered as primary litter decomposition parameters. The higher the C/N ratio and lignin are, the slower litter decomposition is, and low N concentration is unfavorable for litter decomposition, Soil animals and microorganisms are important in litter decomposition. Elevated CO2 concentration influences litter decomposition indirectly by decreasing litter substrate quality and increasing soil moisture content and changing decomposers. Nitrogen deposition affects litter decomposition by changing N concentration of litter.

关 键 词：凋落物 分解 影响因子 

分 类 号：Q148[生物学—生态学] S718.55[生物学—普通生物学]