Journalartikel

Jahr der Veröffentlichung: 2008

Seiten: 2100-2107

Zeitschrift: Journal of Environmental Quality

Bandnummer: 37

Heftnummer: 6

ISSN: 0047-2425

DOI Link: https://doi.org/10.2134/jeq2007.0544

Verlag: Wiley

Abstract: 
The leaching of colloidal phosphorus (P-coll) contributes to P losses from agricultural soils. In an irrigation experiment with undisturbed soil columns, we investigated whether the accumulation of P in soils due to excess P additions enhances the leaching of colloids and P-coll from sandy soils. Furthermore, we hypothesized that large concentrations of P-coll occur at the onset of leaching events and that P-coll mobilized from topsoils is retained in subsoils. Soil columns of different P saturation and depth (0-25 and 0-40 cm) were collected at a former disposal site for liquid manure and at the Thyrow fertilization experiment in northeastern Germany. Concentrations of total dissolved P, P-coll, Fe-coll, Al-coll, optical density, zeta potential, pH, and electrical conductivity of the leachates were determined. Colloidal P concentrations ranged from 0.46 to 10 mu mol L-1 and contributed between I and 37% to total P leaching. Large P-coll concentrations leached from the P-rich soil of the manure disposal site were rather related to a large P-content of colloids than to the mobilization of additional colloids. Concentrations of colloids and P-coll in leachates from P-poor and P-rich columns from Thyrow did not differ significantly. In contrast, accumulation of P in the Werbellin and the Thyrow soil consistently increased dissolved P concentrations to maximum values as high as 300 mu mol L-1. We observed no first-flush of colloids and P-coll at the beginning of the leaching event. Concentrations of P-coll leached from 40-cm soil columns were not smaller than those leached from 25-cm columns. Our results illustrate that an accumulation of P in sandy soils does not necessarily lead to an enhanced leaching of colloids and P-coll, because a multitude of factors independent from the P status of soils control the mobility of colloids. In contrast, P accumulation generally increases dissolved P concentrations in noncalcareous soils due to the saturation of the P sorption capacity. This indicates that leaching of dissolved P might be a more widespread environmental problem in areas with P-saturated sandy soils than leaching of P-coll.

Harvard-Zitierstil: Siemens, J., Ilg, K., Pagel, H. and Kaupenjohann, M. (2008) Is Colloid-Facilitated Phosphorus Leaching Triggered by Phosphorus Accumulation in Sandy Soils?, Journal of Environmental Quality, 37(6), pp. 2100-2107. https://doi.org/10.2134/jeq2007.0544

APA-Zitierstil: Siemens, J., Ilg, K., Pagel, H., & Kaupenjohann, M. (2008). Is Colloid-Facilitated Phosphorus Leaching Triggered by Phosphorus Accumulation in Sandy Soils?. Journal of Environmental Quality. 37(6), 2100-2107. https://doi.org/10.2134/jeq2007.0544