The Diversity Of Nematodes In Aciculiailvae Burned Area Of Alpine Region In Batang County

Forest fire is a natural phenomenon that occurs frequently, but also a special kind of ecological factors, have an important impact on the succession and development of the entire forest ecosystems and forest underground soil ecosystem. After the fire, forest fires can make direct or indirect effects on soil ecosystems, which can make an important effect on soil nutrients-circle as well as carbon-cycle and nitrogen-cycle that soil organisms involve in, but current research focuses on physicochemical properties after fire in the Chinese Northeast forests, but research of soil nematode communities in Alp region after fire research is still very scarce. This paper selects western Sichuan Alpine region's Pinus densata forests' and spruce-fir forests' burned area as well as the corresponding underground soil for the study of soil physical and chemical properties of soil and soil nematodes community around the fire investigation of soil nematodes species diversity, community composition and function of group characteristics by changing circumstances after the fire, The results help to understand the changes in soil nematode community structure and function after the fire, also help to understand the relationship between soil nematodes community change with soil physical and chemical properties changes, and also helps to understand the impact of fire on soil structure and function, and thus for the protection and evaluation of soil ecosystem health, ecological restoration after the fire provide the theoretical basis and background data support. The main conclusions are as follows:(1) After the fire, significant changes have taken place in the soil physical and chemical properties because of the high temperature and combustion, slash the loss of organic matter, soil water retention capacity decreased, decreased fertility and sustainability, in addition to elevated nitrate occurred in the case shortly after the fire, other indicators have different degrees of decline, after a long period of recovery, a variety of physical and chemical indicators have also been varying degrees of recovery, but did not recover to the level before the fire.(2) On nematode number of individuals of different soil Burned and findings genus dominance suggests that fire has a certain influence on soil nematode communities in individual number and the genus dominance, it reduces the amount of soil nematodes, and in the subsoil the performance of different trends. While changing the nematode dominance dominant genera, but did not cause a significant impact on the species of the genus.(3)Different Burned nematode trophic group composition analysis found that fire so that plant-parasitic nematodes(PP), the number of bacteria-feeding nematodes(Ba) and fungal-feeding nematodes(Fu) are reduced, but the prey omnivorous nematode(OP) and no significant impact on the law, suggesting that extreme water stress changed the community structure of the food web composition. Fire changed the way nematode communities decomposition of organic matter. Still on the ground exploded main ways to the main route of bacterial decomposition, soil organic matter decomposition fire way to offset fungal decomposition pathways.(4)Soil nematode communities is closely related to soil physical and chemical properties, the total number of nematodes in different types of samples of Underground and soil moisture rates showed significant positive correlation; in the alpine pine plots, and ammonium was a significant positive correlation, soil total carbon, total nitrogen in soil was significantly positive correlation between bacteria-feeding nematodes with various physical and chemical indicators are consistent with the total number of nematodes; in spruce-fir plots, the total number of nematodes and full carbon and nitrate was significantly positively correlated relationship.