Evaluating the Taiwanese Nitrogen Footprint of Food Production

Ming-Chien Su1, Hideaki Shibata2, James N Galloway3, Allison M Leach4

1 Department of Natural Resources and Environmental Studies, National Dong Hwa University, No. 1, Sec.2, Da Hsueh Rd, Shoufeng, Hualien 97401, Taiwan , mcsu@mail.ndhu.edu.tw

2 Field Center for Northern Biosphere, Hokkaido University; Kita-9, Nishi-9, Kita-ku, Sapporo, Hokkaido 060-0809, Japan

3 Environmental Sciences Department, University of Virginia, Charlottesville, VA 22904, USA

4 Department of Natural Resources and the Environment, University of New Hampshire, Durham, New Hampshire 03824, USA

Abstract

The emissions of reactive nitrogen (Nr) have been well known to cause many environmental problems and human health issues. Recently, the nitrogen (N) footprint indicator has been developed and used to specify the influence of the human use of reactive nitrogen on the environment. Taiwan’s Virtual Nitrogen Factors (VNFs; factors that describe average N losses during food production by food type) are similar to Japan’s VNFs (without accounting for trade) possibly due to comparable dietary and farming technologies. The average VNF of fruit is much higher than other vegetable products. Comparisons of the VNFs between Taiwan and Japan (without trade) follow the same pattern. The 10-year average total food production N footprint in Taiwan was 28 kg N/capita/yr. Furthermore, the N footprints for vegetable and animal products were 10 and 18 kg N/capita/yr, respectively. The results showed that the Taiwan N footprint is highly dependent on food production processes per unit of Nr consumed. We are focusing on domestic food production in Taiwan, but a next step for this study will be to also consider where the food consumed in Taiwan was produced (e.g., imports).