Geographical review of Japan, Series B.
Online ISSN : 2185-1700
Print ISSN : 0289-6001
ISSN-L : 0289-6001
Energy Efficiency of Crop Production in Japan, 1970-1990
Takaaki NIHEI
Author information

2000 Volume 73 Issue 1 Pages 27-45


Graduate student, Institute of Geoscience, University of Tsukuba, Abstract: A large amount of fossil fuel energy is used in modern agriculture. From an ecological aspect, the fossil fuel energy fixed in industrial products such as chemical fertilizers and herbicides makes agriculture inefficient. Agricultural practice needs to be aware of energy efficiency to implement low input management and to reduce the environmental impact. This study demonstrates a method of calculating the input-output energy ratio for 32 crops and examines the changes in the energy efficiency of crop production in Japan from 1970 to 1990. The results at the country level show that the input-output energy ratio changed from 2.0 to 1.2 in the two decades. The primary reason for this decline is due to the increase in the planted area of greenhouse vegetables, whose input-output energy ratio is 0.02-0.07. The secondary reason for this decline is due to the decrease in the planted area of paddy rices, whose input-output energy ratio is 2.5-3.1. The results at the prefecture level show that the input-output energy ratio declines especially in Kochi, Kumamoto and Okinawa prefecture, whose percentages of planted area of greenhouse vegetables are more than three times larger than the average for all the prefectures. The results presented also imply that agriculture in Japan has increased its impact on the natural environment through an increased use of fossil fuel energy.

Information related to the author
© The Association of Japanese Gergraphers
Previous article Next article