Livestock farming systems and sustainable drinking water production: proposition of risk indicators at different organisational levels

Abstract

In the north-east of France, livestock farms, mainly dairy cattle farms, increasingly attempt to replace grass fodder by silage maize. This evolution of agricultural practices modifies the quality of groundwater for human consumption. We propose three indicators of diffuse nitrate pollution risk at three organisational levels: (i) the livestock unit: a ‘hydro-appraisal’ based on cattle feeding management is calculated for the dairy and the fattening units of the Experimental Research Station of Mirecourt, in order to compare the pollution risks due to the production schemes (dairy cows fed with grass against maize, beef steers fed with grass against beef calves fed with maize); (ii) the livestock farm: an indicator based on the cropping plan and on the mean nitrate leaching under the main cropping and grassland systems is calculated on twelve livestock farm types classified from 2211 farms in Lorraine, in order to identify the farming systems that present a pollution risk; (iii) the livestock farming region: the previous indicator is located at the French commune scale by taking into account the proportion of farm types and the relative farming area used by each type, in order to differentiate geographic areas according to the estimated pollution risk. The construction and the combining of such indicators contribute to the development of decision support tools for those concerned with water resource protection and sustainable agricultural land use in livestock farming regions.