Microbial phosphorus cycling in forest soils as dependent on carbon, nitrogen and phosphorus availability

森林土壤中的微生物磷循环取决于碳、氮和磷的可用性

• 批准号: 240974630
• 负责人: Professorin Dr. Marie Anneke Spohn
• 金额: --
• 依托单位: Swedish University of Agricultural Sciences
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2013
• 资助国家: 德国
• 起止时间: 2012-12-31 至 2020-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/240974630?language=en
• 关键词: Microbial; phosphorus; cycling; forest; soils

Microbial phosphorus (P) cycling is crucial for forest nutrition. Previous research focused on microbial biomass P stocks and phosphatase activity, but little is known about the rates of microbial P cycling processes such as solubilization of bound P, turnover of P in the microbial biomass, and net P mineralization. The objective of this project is to gain understanding of microbial P cycling depending on carbon (C), nitrogen (N) and P availability in beech forest soils. The general hypothesis of the project is that rates of microbial P cycling depend strongly on C and P availability. We will, first, study net P mineralization rates, phosphatase activity and microbial P immobilization in a full factorial N and P application experiment in beech forests. We will, second, quantify the mean residence time of C and P in the microbial biomass by labeling microbial DNA with 14C and 33P in a girdling experiment and in forest soils differing in P availability. Third, we will determine the capacity of microbial communities to solubilize P based on incubation experiments with soil extracts and added mineral P. This will be the first study to determine the mean residence time of C and P in the microbial biomass by labeling microbial DNA with 14C and 33P. The main value of the project will be that it relates rates of microbial P cycling in forest soils to C, N and P availability.

微生物磷循环是森林营养的关键。以往的研究主要集中在微生物生物量磷库存和磷酸酶活性，但鲜为人知的是，微生物磷循环过程，如溶解结合磷，营业额的微生物生物量，和净磷矿化率。本项目的目的是了解微生物磷循环取决于碳（C），氮（N）和磷的有效性在山毛榉森林土壤。该项目的一般假设是微生物磷循环速率在很大程度上取决于C和P的可用性。首先，我们将研究净磷矿化率，磷酸酶活性和微生物磷固定在一个全因子的N和P应用实验在山毛榉林。我们将，第二，量化的平均停留时间的C和P的微生物生物量标记微生物DNA与14 C和33 P在环剥实验和不同的森林土壤中的P的可用性。第三，我们将确定微生物群落的能力，以土壤提取物和添加矿物P的培养实验的基础上溶解P。这将是第一次研究，以确定平均停留时间的微生物生物量的C和P标记微生物DNA与14 C和33 P。该项目的主要价值在于它将森林土壤中微生物磷循环速率与碳、氮和磷的有效性联系起来。