【目的】探讨降雨-径流过程中土壤溶解态磷向水体迁移的规律及其影响因素。【方法】采用无界径流小区法以及盆栽试验和模拟试验研究贵州中部黄壤早地磷释放及影响因素。【结果】早地向水体释放的磷量受施磷水平以及玉米生长过程的影响;在高磷黄粘泥土上施磷肥(P2O5)150~900kg·ha^-1,其渗透水中活性磷的平均含量达0.020~0.137mg·L^-1。早地向水体释放的磷量还受环境因子的影响,在温度为30~35℃、水土比为15:1~25:1、淹水时间为12~18h、酸雨pH值为3.82-3.43的条件下,土壤磷的释放量显著地增加。【结论】不同类型黄壤早地地表径流中活性磷(磷酸根态磷)含量存在明显的差异,活性磷含量与土壤有效磷存在显著的正相关,与土壤无定型铝和有机质含量存在密切的负相关。
[Objective] Soil phosphorus release to the water bodies in the upland fields of yellow soil areas and influencing factors was studied in Guizhou province. [ Method ] Adopting by the no boundary runoff little section, pot and simulating experiment. [ Result] The results showed that the content of dissolved active P of surface runoff from various upland fields of yellow-soil were significantly different, which the concentrations of dissolved active P of runoff correlated with the contents of available-P, amorphous oxides of A1, and organic matter in the soils. The amount of soil phosphorus release to the water bodies affected by the level of applying P fertilizer and the process of maize growth. When the fertilizer application rate was from 150 to 900 kg·ha^-1 (P2O5) in the soil with high P level, the average contents of dissolved active P in the penetrated-water of the soil increased from 0.020 mg·L^-1 to 0.137 mg·L^-1. The amount of soil phosphorus release to the water bodies also affected by environmental factors. The amount of soil phosphorus release significantly increased on the conditions that the temperature was 30-35℃, water/soil ratio was 15 : 1 to 25 : 1, submerged-time in water was 12-18 h and pH value of acid rain was 3.82-3.73. [ Conclusion] The content of dissolved active P of surface runoff from various upland fields of yellow-soil was significantly different, which significantly positive and negative correlated with available-P, and amorphous oxides of Al and organic matter in the soils, respectively.