Repeated phosphorus (P) inputs can lead to the accumulation of surplus P in soil with enhanced potential risk of transfer and accelerated eutrophication of aquatic environments. Intensive pork production in Rio Grande do Sul in southern Brazil results in the generation of large quantities of P-rich waste in the form of pig slurry, which is used to fertilise crops. The aim of this study was to assess and quantify the impact of repeated application of pig slurry P over 8 years (2000–2007) on the fate of P in a sandy loam soil maintained under a mixed cropping regime. In a replicated field trial, pig slurry was applied at three rates (20, 40, and 80 m³ ha⁻¹), which resulted in cumulative P inputs over the 8-year period of 628, 1256, and 2511 kg P ha⁻¹. Slurry inputs of 20, 40, and 80 m³ ha⁻¹ resulted in the accumulation of 368, 936, and 2039 kg P ha⁻¹ in soil to 60 cm, respectively. A combination of soil storage (59–81 %), crop removal (7–14 %), and total P transfer in surface runoff (5–15 %) accounted for most of the P applied in pig slurry over 8 years. Our results highlight the potential environmental impacts of runoff P losses in long-term waste-amended and intensively managed subtropical coarse-textured soils. Measures to minimise soil erosion and P transfers from land to water bodies are of utmost importance.

重复的磷 (P) 输入会导致土壤中多余磷的积累，从而增加潜在的转移风险并加速水环境的富营养化。巴西南部南里奥格兰德州的集约化猪肉生产导致大量富磷废物以猪粪的形式产生，用于给农作物施肥。本研究的目的是评估和量化在 8 年（2000-2007 年）内重复施用猪粪磷对混合种植制度下沙壤土中磷命运的影响。在重复的田间试验中，猪粪以三种比例（20、40 和 80 m ³ ha ^-1）施用，这导致在 8 年期间的累积 P 投入量为 628、1256 和 2511 kg P ha ^{- 1}. 输入 20、40 和 80 m ³ ha ^-1的泥浆分别导致土壤中 368、936 和 2039 kg P ha ^-1累积至 60 cm。土壤储存 (59–81%)、作物清除 (7–14%) 和地表径流中总磷转移 (5–15%) 的组合占了 8 年来在猪粪中施用的大部分磷。我们的研究结果突出了径流磷损失对长期废物改良和集中管理的亚热带粗质地土壤的潜在环境影响。最大限度减少土壤侵蚀和磷从土地向水体转移的措施至关重要。