Regional nitrogen budgets: Approaches and problems

Abstract

Regional nitrogen budgets are useful for assessing what is known about nitrogen cycling in important ecosystems of a region, for placing the various regional fluxes and pools into perspective, and for providing insight into the processes that regulate both regional and global nitrogen cycling. Existing regional budgets have been used both to study groundwater nitrate pollution and to help identify local ecosystems that are important on a land-use basis but that are poorly described biogeochemically. Avoidable problems common to many budgets include inappropriate compartment components, inadequate documentation, and unjustified certainty, Though imprecise, large-scale nutrient budgets at our present stage of understanding offer to researchers and system managers important advantages that would otherwise not be available.