Production of organic fertilizers from poultry manure may compromise availability of phosphorus (P) to plants. This study examined the effects of granulation, feather meal addition, and pyrolysis on bioavailability of P in broiler manure in a pot experiment with ryegrass and assessed whether P availability is enhanced by inoculating arbuscular mycorrhizal fungi (AMF) into soil. Granulated broiler manure gave similar plant yield and P uptake to superphosphate. Feather meal addition had a minor negative effect on P availability, whereas pyrolysis lowered the fertilization effect of broiler manure. The yield-based mineral-P equivalences were 120%, 85% and 75% during the first harvest, and 100%, 75% and 45% during one growing season for granulated unamended, granulated amended with feather meal and pyrolyzed broiler manure. Soil inoculation with AMF did not enhance P availability. Granulated poultry manure is suitable as a P fertilizer for annual crops with comparable bioavailability to mineral fertilizer P, whereas pyrolyzed poultry manure is suitable as a slow-release or storage P fertilizer in slightly acidic soils. Knowledge on P bioavailability in organic fertilizers produced with different technologies can be used for optimizing fertilization, minimizing build-up of soil P and its adverse environmental effects.

从家禽粪便生产有机肥料可能会损害植物对磷的利用。这项研究在黑麦草盆栽试验中考察了制粒，添加羽毛粉和热解对肉鸡粪中P的生物利用度的影响，并评估了通过向土壤中接种丛枝菌根真菌（AMF）是否提高了P的利用度。颗粒状的肉鸡粪肥使植物的产量和过磷酸钙的吸收量相近。添加羽毛粉对磷的利用率影响较小，而热解降低了肉鸡粪肥的施肥效果。在未收获的颗粒状未经修饰的，用羽毛粉和热解的肉鸡粪肥进行修正的情况下，第一次收获时基于产量的矿物质-P当量分别为120％，85％和75％，在一个生长季节中分别为100％，75％和45％。用AMF接种土壤不会提高磷的利用率。粒状家禽粪便适合作为生物肥利用率与矿物肥料P相当的一年生作物的P肥料，而热解家禽粪便适合作为在弱酸性土壤中的缓释或储存P肥料。有关使用不同技术生产的有机肥料中磷生物利用度的知识可用于优化施肥，最大程度减少土壤中磷的积累及其对环境的不利影响。