Estimating the effect of legislation on nitrogen leaching by upscaling field simulations

Abstract The aim of this article is to present an approach for estimating nitrogen (N) leaching on a regional scale, e.g. municipality and country. This approach is used in scenario studies of the effects of implementation of legislation on the N fertilization schedules on N leaching. On the basis of simulated results obtained with the deterministic simulation model DAISY by Hansen et al. (Fert. Res. 27 (1991) 245–259.), for different combination of farm types, N-fertilization schedules, soil types, irrigation and climate, a statistical model called General Nitrogen Leaching model (GNL-model) is set up. The model describes the average annual N leaching as a linear function of the number of livestock units per hectare for the selected class variables. The GNL-model is used in a regional model to simulate N leaching at municipality level, in the mid-eighties and after full implementation of the legislation. As input to the regional model are statistical farm data (farm type, number of animals, cultivated area, and irrigated area) in 1985 and 1994 and soil data. Soil data is represented by soil types as distributed at municipality level. The results simulated at municipality level are summarized to give the national level. N leaching was found to be ca. 200 000 t N ha −1 year −1 in the mid-eighties and ca. 130 000 t N ha −1 year −1 after full implementation of the legislation. It was found that the approach worked well in estimating the effect of the changes in N fertilization schedules caused by implementation of the legislation.

[1]  Søren Hansen,et al.  Simulation of crop production, water and nitrogen balances in two German agro-ecosystems using the DAISY model , 1995 .

[2]  R. Wagenet,et al.  Simulating nitrogen dynamics in soils using a deterministic model , 1991 .

[3]  O. H. Sørensen,et al.  Measurement of regional bone mass in normals and in osteoporotics , 1994 .

[4]  Nitrogen Modeling on a Regional Scale , 1991 .

[5]  W. G. Knisel,et al.  GLEAMS: Groundwater Loading Effects of Agricultural Management Systems , 1987 .

[6]  S. E. Simmelsgaard.  The effect of crop, N‐level, soil type and drainage on nitrate leaching from Danish soil , 1998 .

[7]  J. Bouma,et al.  Use of soil survey data for modeling solute transport in the vadose zone , 1996 .

[8]  L. M. Svendsen,et al.  Loss of dissolved and particulate phosphorus from arable catchments by subsurface drainage , 1996 .

[9]  S. R. Workman,et al.  Using GIS in Simulation of Nitrate Leaching from Heterogeneous Unsaturated Soils , 1996 .

[10]  S. E. Simmelsgaard,et al.  An empirical model for estimating nitrate leaching as affected by crop type and the long‐term N fertilizer rate , 1998 .

[11]  Bernd Diekkrüger,et al.  Validity of agroecosystem models a comparison of results of different models applied to the same data set , 1995 .

[12]  P. de Willigen,et al.  Nitrogen Turnover in the Soil-Crop System , 1991, Developments in Plant and Soil Sciences.

[13]  Søren Hansen,et al.  Parameter assessment for simulation of biomass production and nitrogen uptake in winter rape , 1995 .

[14]  Lars Bergström,et al.  Simulated nitrogen dynamics and losses in a layered agricultural soil , 1987 .

[15]  Leif T. Jensen,et al.  A comparison of the performance of nine soil organic matter models using datasets from seven long-term experiments , 1997 .

[16]  Pierre Estienne,et al.  Atlas of Denmark. , 1951 .

[17]  Ole H. Jacobsen,et al.  Modelling mean nitrate leaching from spatially variable fields using effective hydraulic parameters , 1999 .

[18]  P. Sørensen,et al.  GIS-based modelling of solute fluxes at the catchment scale: a case study of the agricultural contribution to the riverine nitrogen loading in the Vejle Fjord catchment, Denmark , 1998 .