Synergy of Biochar and Organic Fertilizer Reduces Phosphorus Leaching

作者：Danni Ma, Yaofeng Wang, Tong Zheng, Qixing Zhou, Jiandong Sheng · 发表于：Agronomy · 年份：2025 · DOI：10.3390/agronomy15112528 · 被引用次数：4 · 研究领域：Phosphorus and nutrient management、Soil and Water Nutrient Dynamics、Soil Carbon and Nitrogen Dynamics

To address rising global food demand, improving phosphorus (P) use efficiency in agriculture is crucial. Organic fertilizers and biochar are recognized for their potential to improve soil phosphorus availability and reduce environmental losses. However, the synergistic effects of their combined application on phosphorus retention and transformation have received insufficient attention. This study investigated the synergy between cow dung-derived biochar (produced at 400 °C and 700 °C) and organic fertilizer using P fractionation, leaching, and extraction tests. Results indicated that the H2O-P content in organic fertilizer as high as 42.17 mg·g−1, resulting in a cumulative leaching loss of up to 11.62 mg·g−1. In contrast, biochar exhibited lower leaching due to more stable C–P compounds, as confirmed by X-ray photoelectron spectroscopy (XPS). When biochar and organic fertilizer were co-applied, complexation with Ca2+ on their surfaces reduced phosphorus leaching from the mixture by 83.69%. The formation of Ca2P2O7 crystals, detected through X-ray diffraction (XRD), indicates a strong synergistic effect between biochar and organic fertilizer. Additionally, the porous structure of biochar adsorbed phosphorus from organic fertilizer, further inhibiting leaching losses. This synergy enhances P retention, offering an effective strategy to improve P use efficiency and support sustainable soil management.