Holland is a country whose land is suffering from nitrogen pollution and, accordingly, the government has been driven to undertake strict measures towards the livestock industry.
According to assistant professor Masaya Ishikawa, an agro-environmental engineering specialist at the Faculty of Agriculture, Yamagata University, Holland has introduced a policy of minerals accounting system (MINAS), which
seeks to enforce a 10% reduction in pig numbers, while urging the industry to clarify the use of treated animal waste and, furthermore, imposing a surcharge tax on those farmers who violate the standards set by the government from 2002.
On the other hand, Mr. Hakamata indicated that, in terms of square meter of farmland, the amount of nitrogen imported into Japan far exceeds that imported into Holland. Despite of that, Japan is less polluted than Holland.
In response to this, Director Harada of the National Agricultural Research Center explains that “it is because Japan is shaped by its rainy weather and swift rivers, which results in flushing wastes from all Japanese lands.”
Another reason is rice paddies. In general, growing rice requires a lesser quantity of chemical fertilizers than vegetables. In addition, micro-organisms living in paddies act on nitrogen, converting it into nitrogen gas, which is harmless to the environment. Mr. Toshio Tabuchi, a former professor of paddy field engineering at the University of Tokyo, points out that “quantitative measurement is difficult, but there is no doubt that actions to remove nitrogen from Japanese rice paddies have been making a significant contribution to the purification of Japan.”
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Herald Tribune/Asahi
Holland: Limiting the number of pigs reared