Personal nitrogen footprint tool for the United Kingdom

Abstract

The global nitrogen (N) cycle has been transformed by human use of reactive N as a consequence of increased demand for food and energy. Given the considerable impact of humans on the N cycle, it is essential that we raise awareness amongst the public and policy makers as this is the first step in providing individuals and governments the opportunity to reduce their impact on the N cycle and reduce the environmental and health consequences of N pollution. Here we describe an N footprint tool for the UK developed as part of the N-PRINT program. The current per capita N footprint in the UK is 27.1 kg N per capita per year with food production constituting the largest proportion of the footprint (18.0 kg N per capita per year). Calculating an N footprint for 1971 (26.0 kg N per capita per year) demonstrates that per capita N footprints have increased slightly. The average UK footprint is smaller than that found in the USA but is higher than the Netherlands and Germany. Scenario analysis demonstrates that reducing food protein consumption to the levels recommended by the FAO and World Health Organization reduces the overall N footprint by 33%. Consuming a vegetarian diet and consuming only sustainable food both decreased the N footprint by 15% but changes in energy use have a much smaller impact.

Nitrogen footprints: Regional realities and options to reduce nitrogen loss to the environment

“…The total N footprint in Japan was comparable to European countries and smaller than the USA (Table 1; Leach et al 2012). VNFs for meat and animal products produced in Japan were relatively high compared to the USA and Europe ( Table 2; Leach et al 2012;Stevens et al 2014). Incorporating international food and feed trade reduced most VNFs and the overall food N footprint in Japan.…”

“…The most common property of the per capita N footprint is the dominance of the food N footprint (Leach et al 2012;Galloway et al 2014;Shibata et al 2014). In all countries VNFs for crop products are lower than for animal products (Table 2; Leach et al 2012;Galloway et al 2014;Pierer et al 2014;Shibata et al 2014;Stevens et al 2014).…”

“…Stevens et al (2014) examined how the N footprint in the UK has changed and increased slightly over time. Through scenario analysis, they demonstrated how shifting diets to food protein consumption levels recommended by the FAO and WHO can reduce the N footprint.…”

“…Several N footprints have been developed for European countries: the UK (Stevens et al 2014), Austria (Pierer et al 2014), the Netherlands (Leach et al 2012), Portugal and Germany (Stevens et al 2014) (Table 1), ranging from 24 to 29 kg N capita -1 year -1…”

“…Per capita N footprints have been calculated for the USA, Netherlands, Germany, UK, Austria, and Japan using the N-Calculator model (Leach et al 2012;Galloway et al 2014;Shibata et al 2014;Stevens et al 2014), and are in development for Australia, China, Denmark, Portugal, Taiwan, and Tanzania (Table 1). N footprints have also been calculated for China (Gu et al 2013a), the European Union (Leip et al 2014b), and 188 countries (Oita et al 2016a) using a top-down N balance approach.…”