Footprint tools tiptoeing towards nitrogen sustainability

As we face multiple environmental crises (e.g., climate change, nutrient pollution, freshwater scarcity), there is often a disconnect between an entity’s activities and the pollution resulting from that activity. Footprint tools help address this disconnect. Footprint tools are effective in educating people, institutions and communities on how their resource use results in environmental pollution and what we can do to moderate that pollution. These tools connect an entity’s activities with the associated pollution. Footprint tools are also constantly evolving. As we better understand how to best estimate emissions – especially from sources further removed like those from the supply chain – the guidance and methods for calculating footprints is changing and improving. This paper reviews footprint tools for people, institutions and communities, with a focus on nitrogen footprint tools. It also gives examples of how these tools have been applied to achieve pollution reductions. It concludes with an assessment of how nitrogen and multi-element footprint tools fit into the overall topic of environmental management and discusses their benefits and limitations.