Mapping nitrate leaching to upper groundwater in the sandy regions of The Netherlands, using conceptual knowledge |
| |
Authors: | Leo Boumans Dico Fraters Gerard van Drecht |
| |
Institution: | (1) National Institute of Public Health and the Environment (RIVM), 1, 3720 BA Bilthoven, The Netherlands |
| |
Abstract: | The European Community asks its Member States to provide a comprehensive and coherent overview of their groundwater chemical
status. It is stated that simple conceptual models are necessary to allow assessments of the risks of failing to meet quality
objectives. In The Netherlands two monitoring networks (one for agriculture and one for nature) are operational, providing
results which can be used for an overview. Two regression models, based upon simple conceptual models, link measured nitrate
concentrations to data from remote sensing images of land use, national forest inventory, national cattle inventory, fertiliser
use statistics, atmospheric N deposition, soil maps and weather monitoring. The models are used to draw a nitrate leaching
map and to estimate the size of the area exceeding the EU limit value in the early 1990s. The 95% confidence interval for
the fraction nature and agricultural areas where the EU limit value for nitrate (50 mg/l) was exceeded amounted to 0.77–0.85
while the lower 97.5% confidence limit for the fraction agricultural area where the EU limit value was exceeded amounted to
0.94. Although the two conceptual models can be regarded as simple, the use of the models to give an overview was experienced
as complex. |
| |
Keywords: | Water Framework Directive Nitrate Directive Monitoring Field survey Regression analysis GIS |
本文献已被 PubMed SpringerLink 等数据库收录! |
|