土壤动物对三江平原典型毛果苔草湿地枯落物分解的影响

采用尼龙网分解袋法，从枯落物的分解量、组分含量和分解残留物的热能值3方面，研究了土壤动物对三江平原毛果苔草（Carex lasiocarpa）湿地枯落物分解的影响。结果表明，土壤动物加速了枯落物的分解，大中型土壤动物的分解作用大于小型土壤动物；土壤动物增加了枯落物中腐殖酸、纤维素和木质素等物质含量以及C／N比值的变化幅度，促进了枯落物组分的释放；土壤动物影响枯落物分解过程中的能量流动；但土壤动物并未影响枯落物分解的总体变化趋势，土壤动物对枯落物分解不起决定性作用。

Effect of Soil Fauna on Decomposition of Litters in Carex lasiocarpa Wetland in Sanjiang Plain

Effect of soil fauna on decomposition of litters in Carex lasiocarpa wetland in Sanjiang Plain was studied with the litter bag technique,through analyzing decomposition rate and component contents of the litters and calorific value of the residue of decomposition.Results indicate that 1) soil fauna accelerated decomposition of the litters and the effect of macrofauna and mesofauna was more significant than that of microfauna;2) it increased concentrations of cellulose,lignin and humic acids and variation of C/N ratio of the litters,which was more significant in 16 mesh-bags than in 250 mesh-bags,suggesting that soil fauna accelerated release of components from the litters;3) the calorific value of the residue of decomposition was significantly different between 16 mesh-bags and 250 mesh-bags,suggesting that energy flow from decomposition of the litter was affected by soil fauna;and 4) soil fauna,however,did not affect much the general tendency of the decomposition,that is to say,soil fauna is not a decisive factor of the decomposition process of the litters.