Validation of regression models for nitrate concentrations in the upper groundwater in sandy soils
| Autor: | J. Roelsma, M.P.W. Sonneveld, Dick J. Brus |
|---|---|
| Rok vydání: | 2010 |
| Předmět: |
CB - Bodemgeografie
Health Toxicology and Mutagenesis netherlands Toxicology nitrogen Leerstoelgroep Landdynamiek Soil chemistry.chemical_compound Nitrate leaching losses Linear regression Water Movements Alterra - Centre for Water and Climate SS - Soil Geography Land Dynamics regions Alterra - Centrum Bodem Wageningen Environmental Research agriculture Hydrology Models Statistical Nitrates Soil Science Centre Linear model Soil classification Regression analysis General Medicine CWK - Integraal Waterbeheer Silicon Dioxide PE&RC farms Pollution chemistry Soil water Environmental science CWC - Integrated Water Resources Management Frequency distribution limits performance Groundwater Environmental Monitoring Alterra - Centrum Water en Klimaat |
| Zdroj: | Environmental Pollution, 158(1), 92-97 Environmental Pollution 158 (2010) 1 |
| ISSN: | 0269-7491 |
| DOI: | 10.1016/j.envpol.2009.07.033 |
| Popis: | For Dutch sandy regions, linear regression models have been developed that predict nitrate concentrations in the upper groundwater on the basis of residual nitrate contents in the soil in autumn. The objective of our study was to validate these regression models for one particular sandy region dominated by dairy farming. No data from this area were used for calibrating the regression models. The model was validated by additional probability sampling. This sample was used to estimate errors in 1) the predicted areal fractions where the EU standard of 50 mg l-1 is exceeded for farms with low N surpluses (ALT) and farms with higher N surpluses (REF); 2) predicted cumulative frequency distributions of nitrate concentration for both groups of farms.Both the errors in the predicted areal fractions as well as the errors in the predicted cumulative frequency distributions indicate that the regression models are invalid for the sandy soils of this study area.This study indicates that linear regression models that predict nitrate concentrations in the upper groundwater using residual soil N contents should be applied with care |
| Databáze: | OpenAIRE |
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