Vulnerability of groundwater resources to nitrate pollution: A simple and effective procedure for delimiting Nitrate Vulnerable Zones

摘要: Abstract This research was undertaken to further our understanding of the factors involved in nonpoint-source nitrate pollution groundwater. The shortcomings some most commonly used methods for assessing groundwater vulnerability have been analysed and a new procedure that incorporates key improvements has proposed. approach (LU-IV procedure) allows us assess map accurately delimit Nitrate Vulnerable Zones. LU-IV proved more accurate than widely (DRASTIC, GOD), when compared with distribution 46 aquifers included study (using drainage basin as unit analysis). proposed stands out by meeting following requirements: (1) it uses readily available parameters provide enough data feed model, (2) excludes redundant parameters, (3) avoids need assign insufficiently contrasted weights (4) whole catchment area potentially drains N-polluted waters into receptor aquifer, (5) can be implemented within GIS, (6) provides multi-scale representation. As demonstrated reliable tool delimiting NVZ, could particularly interesting use countries where certain types environmental are either not or only limited availability. Based on this (and according procedure), concluded an at least 1728 km 2 should considered NVZ. sharply contrasts current 328 km officially designated Spain's regional administrations. These results highlight redefine NVZ designation, which is essential appropriate implementation action programmes designed restore water quality line Directive 91/676/EEC.