Study On Soil Fauna’s Function In Litter Decomposition Of Dominant Species In Korean Pine Broad-leaved Mixed Forest On Changbai Mountain

Plant Litter decomposition is an essential pathway to return nutrient in terrestrial ecosystem.Soil fauna are considered to be an important factor in the acceleration litter decompositionand nutrient transformations. Mechanisms of soil faunal contribution to litter decompositioninclude digestion of substrates, increase of surface area through fragmentation andacceleration of microbial inoculation into litter. In this paper, we conducted a litterdecomposition experiment using litterbag method in Pinus koraiensis mixed broad-leavedforest in Changbai Mountains to explore the contribution of soil fauna on litter decomposition,The present study will not only be a great performance of the theory of soil fauna ecology, butalso provide a scientific basis for maintaining a balanced and sustainable development offorest ecosystems of Changbai Mountain.We used litterbags with different mesh sizes to examine the decomposition process of fourdominant tree species in studied site: Pinus koraiensis, Fraxinus mandshurica, Tiliaamurensisa, Acer mono. In all three different mesh litterbags, the remaining mass of the Pinuskoraiensis were the highest, while the Fraxinus mandshurica were the lowest. Before August2010, the remaining mass of Tilia amurensis and Acer mono were so close, but at the end ofthe studying period, the remaining mass of Tilia amurensis were obviously less than Acermono. In a word, the decomposing rates of four species litter were roughly arranged like that:Fraxinus mandshurica> Tilia amurensi> Acer mono> Pinus koraiensis.During2009and2010, we got52groups of soil fauna were found in litterbags during theexperiment, which total of11373belonged to3phyla,8class,22orders and44families. Thedominant groups were Isotomidae, Oribatida and Hypogastruridae; and the common groupswere Gamasida, Tomoceridae, Pseudachorutidae, Actinedida, Diptera, Enchytraeidae andParonellidae. Simultaneously, we got60groups soil fauna in situ, which total of8655belonged to3phyla,8class,22orders and48families. The dominant groups were Oribatida,Isotomidae and Hypogastruridae; and the common groups were Actinedida, Gamasida,Enchytraeidae, Pseudachorutidae, Tomoceridae and Diptera.The main soil fauna in litter decomposition including Collembola, Arachnida, Diptera,Lumbricidae, Enchytraeidae, Chilopoda, Juliformia, Lepidoptera, Coleoptera and Gastropoda,among them, Isotomidae and Oribatida are the most dominant groups in all species litter.The result of the Pearson correlation analysis showed that the remaining mass of Pinuskoraiensis had extreme significantly negative relation with soil fauna individual number(P<0.01), and evenness index (P<0.01). The remaining mass of Tilia amurensi had extremesignificant negative relation with soil fauna individual number only (P<0.01). The remainingmass of Fraxinus mandshurica had extreme significant negative relation with soil faunaindividual number (P<0.01), and significant positive relation with evenness index (P<0.01),but only had significant positive relation and negative relation with d iversity index anddominance index (P<0.05), respectively. The remaining mass of Acer mono had extreme significant negative relation with dominance index only (P<0.01).