Grasslands arebeing replaced by urbanization and more profitable agricultural activities aroundthe world. Producers may be faced with land constraints and need to considerintensification of the remaining grasslands as a means of maintaining overallproduction on a decreasing land resource. However, intensification of the grazingsystem is usually associated with greater nutrient inputs, including those fromcommercial fertilizers and supplement fed to animals. Excessive loading of nutrientsin intensive grazing systems via fertilizer and animal wastes can cause nutrientbuildup in the soil and subsequent water quality problems. Surface runoff andleaching of nutrients are the two major process affecting water quality. Nitrogenand P represent major nutrient concerns as related to water quality. Increasednitrate concentrations render groundwater unsuitable for drinking and can causeserious health issues for humans. Excessive N and P concentrations may contributeto eutrophication of streams and lakes. Maximizing efficiency of nutrient recyclingthrough the soil-forage-animal system minimizes off-site nutrient transportand decreases production costs by reducing the quantity of commercial fertilizerneeded. Management strategies to reduce soil and water contamination includerefining the balance of nutrient inputs from feeds and fertilizers as well asaccounting for the nutrients recycled through the decomposition of plant litterand animal wastes. Current interest in the development and adoption of efficientand sustainable agriculture systems has led forage researchers to amplify thescope of grasslands research by increasing multidisciplinary efforts. Thereis an increased interest in quantifying the impacts of forage-animal managementstrategies on the environment, with the goal of developing economically viablebest management practices that result in optimum forage production and profitability,while protecting the environment. Furthermore, these best management practiceswill supply reliable information for future environmental policies that maybe adopted by governmental agencies.
