土壤磷素微生物作用的研究进展

Process in research on microbiological action of soil phosphorus

土壤中许多微生物(包括菌根真菌)能够通过产生质子和有机酸溶解土壤不溶态无机磷,通过分泌磷酸酶水解有机磷,但微生物的这种作用受土壤供磷与植物对磷需求间平衡的控制。土壤微生物量中的磷是土壤有机磷最为活跃的部分,由于其周转快、极易矿化为植物有效磷而成为土壤有效磷的活性库。目前,测定土壤微生物量中的磷的方法并不统一,而熏蒸提取法的应用最为广泛。文章阐述了土壤微生物在提高土壤磷素有效性磷中所起的作用,介绍了土壤微生物量中的磷周转及其对土壤磷素有效性调节的重要性,并总结分析了熏蒸提取法测定土壤微生物量中的磷的实用性和局限性。

Soil microorganism not only drives the cycling of organic matter and nutrients but also contains an important resource of plant nutrients in the soil. By exuding protons, organic acids and phosphatases, soil microorganism (bacteria and fungi included) can both dissolve insoluble inorganic phosphorus and hydrolyze organic phosphorus in soil, which process is regulated by the phosphorus equilibrium between soil supply and plant demand. Soil microbial biomass phosphorus, the relatively active fraction of soil organic phosphorus, was often considered as a labile pool of soil available phosphorus because of its short turnover time. At present, the measurement of soil microbial biomass phosphorus was non-uniform, but the fumigation-extraction method was used relatively widely. In this paper the roles microorganism played in improving soil phosphorus availability were illustrated, and the turnover of soil microbial biomass phosphorus and its importance was also reviewed. Moreover, the practicability and limitation of thefumigation-extraction method for measuring soil microbial biomass phosphorus were evaluated.