康平沙地治理过程中土壤微生物数量与土壤肥力的关系

The Relationship Between Soil Microorganism and Soil Fertility in the Process of Transforming Kangping′s Desertification

通过对辽宁省康平县海州乡不同类型土壤的调查、土壤微生物数量的测定,了解退化的生态系统进行植被恢复后土壤肥力的变化情况。采用稀释平板法测定典型土壤和典型植被根际土中微生物数量,结果表明,土壤微生物的数量基本变化趋势为:固定沙丘>半固定沙丘>流动沙丘土;各类型的微生物在不同类型的沙土中分布比例不相同,微生物三大类群总数量排列依次为细菌>放线菌>真菌;半固定沙丘不同地带不同环境中的微生物类群组成和各类群之间的比例各不相同;不同植被在相同的生长地带土壤微生物的组成比例各不相同,其中乔本植被微生物数量高于灌木丛和草本植被。因此,在康平地区植被恢复过程中,应以乔本植被为主,并采用适当的封禁治理措施确保土壤肥力的提高。

Soil samples were collected from Haizhou of Kangping County in Liaoning Province, in order to study different types of soil, determine the amount of soil microorganisms, find ways to change soil fertility by vegetation in the degenerated ecosystem. The changes of microbial numbers both in rhizosphere and non-rhizosphere soils were measured by the dilution method. The plant biomass is compared in various plants in the same growth conditions, and the quality response and the evolution of soil fertility in the process of improving sandy soils are analyzed, to provide a basis in finding the best sand-fixing plants. The results show that in the main changes the order in the soil microorganism quantity is as follows： that in the fixed sand dunes is the highest, and that in the moving sand dunes is the lowest, with that in the semi-fixed sand dunes between them. It is also indicated that various types of microorganisms have different proportions in different types of sand. The number of bacteria is the largest, followed by actinomycetes and the number of fungi is the smallest. In addition, in different environments and in different zones of the semi-fixed dunes, the ratios between the compositions of microbial taxa and various groups are not the same. The different plant growth zones with the same proportion of microbial composition show different features, especially, the amount of plant biomass in Joe plants is greater than that in shrubs and herbaceous plants. So during the vegetation inKangping, more Joe plants should be used, with suitable measures such as ban of grazing, for the soil fertility.