Accumulation of inorganic and labile organic phosphorus (P) in intensive agricultural systems leads to P loss from soil which can cause serious environmental problems. Soil microbes are important in mobilizing soil non‐available P, however, little is known about the role of soil microbes in immobilizing P to reduce P loss. Here, we test whether stimulating microbial biomass to immobilize P could reduce the amount of labile P available for leaching. The distribution characteristics of Olsen P, organic P and microbial biomass P were determined in three intensive agricultural systems. In addition, we conducted a pot experiment with three P and four carbon (C) levels. CaCl₂ extractable P was measured and used to indicate the risk of P leaching. We found that there was a positive relationship between soil organic C and microbial biomass P. Carbon addition drove the process of P immobilization and reduced CaCl₂ extractable P. Microbial biomass P increased by 64% (p < .05) with the addition of C, and Olsen P and CaCl₂ extractable P decreased by 28% and 17%, respectively. Our results show that C addition increased microbial immobilization of P and reduced forms of labile P susceptible to leaching. Stimulating microbes to immobilize P by adding C to soils may have the potential to reduce P loss from intensive agricultural systems, reducing their environmental impact.

中文翻译：

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碳的添加通过增加集约型农业系统中的微生物生物量磷来减少不稳定的土壤磷

集约化农业系统中无机磷和不稳定有机磷（P）的积累导致土壤中磷的流失，这可能导致严重的环境问题。土壤微生物在动员土壤不可利用的磷方面很重要，但是，对于土壤微生物在固定磷以减少磷损失方面的作用知之甚少。在这里，我们测试了刺激微生物生物量以固定磷可以减少可用于淋洗的不稳定磷的数量。确定了三种集约化农业系统中Olsen P，有机P和微生物量P的分布特征。此外，我们进行了三个P和四个碳（C）水平的盆栽实验。氯化钙₂测量可提取的磷并用于指示磷浸出的风险。我们发现土壤有机碳与微生物生物量P之间存在正相关关系。碳的添加推动了磷的固定化过程，并降低了CaCl ₂可提取的磷。随着C的添加，微生物生物量P增加了64％（p  <.05）。 ，Olsen P和CaCl ₂可萃取P分别降低了28％和17％。我们的结果表明，添加C增加了P的微生物固定作用，并减少了易于浸出的不稳定P的形式。通过向土壤中添加C刺激微生物以固定P，可能会减少集约型农业系统中P的损失，从而减少其对环境的影响。