Humans increase the amount of reactive nitrogen (all N species except N2) in the environment through a number of processes, primarily food and energy production. Once in the environment, excess reactive nitrogen may cause a host of various environmental problems. Understanding and controlling individual nitrogen footprints is important for preserving environmental and human health. In this paper we present the per capita nitrogen footprint of Japan.

Livestock operations are known to harbor elevated levels of antibiotic resistance genes (ARGs) that may pose a threat to public health. Broiler feedlots may represent an important source of ARGs in the environment. However, the prevalence and dissemination mechanisms of various types of ARGs in the environment of broiler feedlots have not previously been identified.

Recent studies show that current trends in yield improvement will not be sufficient to meet projected global food demand in 2050, and suggest that a further expansion of agricultural area will be required. However, agriculture is the main driver of losses of biodiversity and a major contributor to climate change and pollution, and so further expansion is undesirable. The usual proposed alternative—intensification with increased resource use—also has negative effects.

Solutions to meet growing food requirements in a world of limited suitable land and degrading environment focus mainly on increasing crop yields, particularly in poorly performing regions, and reducing animal product consumption. Increasing yields could alleviate land requirements, but imposing higher soil nutrient withdrawals and in most cases larger fertilizer inputs.