Phosphorus leaching from an organic and a mineral arable soil in a rainfall simulation study
Phosphorus derived from agricultural systems has been found to cause eutrophication of surface waters. To combat this, the specific location of soil profile P release is necessary for development of effective mitigation strategies. This paper describes a P leaching study of two Swedish arable soils, an organic (Typic Haplosaprist) and a mineral soil (Typic Hapludalf), both with high P content. Undisturbed soil columns isolated 0- to 20-, 20- to 40-, 40- to 60-, and 60- to 80-cm depth intervals. These were placed in a rainfall simulator and subjected to four 50-mm rainfall events to identify the origin of P leachate as a function of soil depth interval and physicochemical properties. Phosphorus losses were greatest from the two uppermost layers of both soils after 200 mm of artificial rainfall was applied at 5 mm h⁻¹. Total P concentration in leachate from the 0- to 20-cm layer ranged from 2.1 to 8.8 mg L⁻¹ for the mineral and 3.7 to 10.3 mg L⁻¹ from the organic soil, with most (95-100%) in dissolved reactive P form. Degree of P saturation correlated well with total P leaching losses from the organic soil (R = 0.84) but not the mineral soil (R = 0.69), suggesting that the presence of Al and Fe (hydr)oxides has a stronger influence on P leaching in the organic soil. Results indicate that both soils have the potential to contribute concentrations of P above those known to cause eutrophication of surface waters.... [Show full abstract]
Keywordsphosphorus leaching; Sweden; soil analysis; organic soil; mineral soil; Agronomy & Agriculture; Phosphorus; Minerals; Soil; Soil Pollutants; Rain; Eutrophication
Fields of Research0503 Soil Sciences; 050304 Soil Chemistry (excl. Carbon Sequestration Science); 04 Earth Sciences; 05 Environmental Sciences; 06 Biological Sciences
© The authors and the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America.