A strategy for the protection of groundwater from nitrate leaching using spatial and geostatistical analyses

摘要

An approach for defining land zones to protect groundwater resources from the effects of agriculturally derived diffuse nitrate pollution is described. The approach operates in two distinct stages. The first stage collates and statistically examines groundwater nitrate data from all available monitoring points. At the same time a number of groundwater vulnerability scenarios are modelled to determine the theoretical risks to groundwater based on land use, climate, soil and (solid and Drift) geological characteristics. The maps derived from this latter exercise are compared with the monitoring data to determine which of the scenarios best predicts the vulnerability of groundwater to nitrate pollution. In the second stage, the spatial distribution of nitrate concentrations is estimated by geostatistical analysis of the monitoring data and is used in conjunction with the selected vulnerability map to define land use zones. Development of the monitoring network and an approach to address anomalies are also described.