Nitrogen fertilization and nitrate leaching into groundwater on arable sandy soils

verfasst von

Kai Köhler, Wilhelmus H.M. Duynisveld, Jürgen Böttcher

Abstract

Nitrate leaching depending on N fertilization and different crop rotations was studied at two sites with sandy soils in N Germany between 1995 and 2000. The leaching of NO₃^- was calculated by using a numerical soil-water and N model and regularly measured N_min values as input data. Also the variability of N_min values on the sandy soils was determined along transects. They reveal the high variability of the N_min values and show that it is not possible to confirm a significant N_min difference between fertilizer treatments using the normal N_min-sampling intensity. Nitrate-leaching calculations of five leaching periods showed that even strongly reduced N-fertilizer applications did not result in a substantially lower NO₃^- leaching into the groundwater. Strong yield reductions of even more than 50%, however, were immediately measured. Mean NO₃^- concentrations in the groundwater recharge are >50 mg L^-1 and are mainly due to mineralization from soil organic matter. Obviously, the adjustment of the N cycle in the soil to a new equilibrium and a reduced NO₃^--leaching rate as a consequence of lower N inputs need a much longer time span. Catch crops are the most efficient way to reduce the NO₃^- concentrations in the groundwater recharge of sandy soils. Their success, however, strongly depends on the site-specific development possibilities of the catch crop. Even with all possible measures implemented, it will be almost impossible to reach NO₃^- concentrations <50 mg L^-1 in sandy soils. The only way to realize this goal on a regional scale could be by increasing areas with lower nitrate concentrations in the groundwater recharge like grassland and forests.

Organisationseinheit(en)

Institut für Bodenkunde
AG Bodenbiophysik

Externe Organisation(en)

Bundesanstalt für Geowissenschaften und Rohstoffe (BGR)

Typ

Artikel

Journal

Journal of Plant Nutrition and Soil Science

Band

169

Seiten

185-195

Anzahl der Seiten

11

ISSN

1436-8730

Publikationsdatum

04.2006

Publikationsstatus

Veröffentlicht

Peer-reviewed

Ja

ASJC Scopus Sachgebiete

Bodenkunde, Pflanzenkunde

Ziele für nachhaltige Entwicklung

SDG 2 – Kein Hunger

Elektronische Version(en)

https://doi.org/10.1002/jpln.200521765 (Zugang: Unbekannt)