Analysis of energy, food, fertilizer and feed: Self-sufficiency potentials

The overall food self-sufficiency rate in Japan is currently under 40 per cent, although in Hokkaido Prefecture it is almost 200 per cent (Ministry of Agriculture, Forestry and Fisheries, 2009). Out of the 47 prefectures in Japan, 5 have food self-sufficiency rates greater than 100 per cent (Hokkaido, 195 per cent; Akita, 174 per cent; Yamagata, 132 per cent; Aomori, 118 per cent; and Iwate 105 per cent) (Ministry of Agriculture, Forestry and Fisheries, 2009). Japan’s energy self-sufficiency rate is only 4 per cent (19 per cent if nuclear power generation is included) (Agency for Natural Resources and Energy, 2008). Most potash and phosphate supplies are imported and dairy farming in Japan is heavily reliant on imported livestock feed. Farmers consume diesel while using farm machinery, chemical fertilizers and insecticides are made from fossil fuels, and transportation of livestock feed from foreign countries by ship consumes fuel. In addition, the storage of harvested crop products requires huge amounts of electricity. As such, agriculture and dairy farming are highly vulnerable to oil price rises. Current agricultural practices may be defined as “converting oil into food” (Saito, 2009). The energy profit ratio, defined as (output energy / invested energy), involved in producing rice was estimated at 2.5 in the 1960s, but by the 1990s the profit ratio had fallen to 0.7 (Sato, 2005). This shift shows that modern rice production, with its large paddy field sizes, has become extremely dependent on large inputs of fossil energy.