BASIC STUDY ON CULTIVATION CHARACTERISTICS OF ENERGY CROPS IN THE HILLY AND MOUNTAINOUS AREAS OF HIROSHIMA PREFECTURE, JAPAN

The use of biomass as an energy source provides a renewable alternative to the burning of fossil fuels. The present study examined low cost, extensive production of bioenergy materials from four energy crops grown on wasteland with controlled release fertilizer (CF-A), Chemical Compound Fertilizer (CFB), Bulk Blended Fertilizer (CF-C), Sewage Sludge Fertilizer (SSF) and Bark Compost (BC). Biomass production subsequent to the application of 100 Kg N/ha using SSF and BC was compared with production subsequent to similar application of CF. Sorghum, Italian ryegrass, rye and oats were cultivated for a period of 2 years (October 2007-October 2009) on plots located on Gleysols at a site belonging to the Prefectural University of Hiroshima (PUH), Japan. Sorghum was also cultivated on fallow paddy fields belonging to neighboring farmers which were located on Andosols and also within a concrete-bordered field on granite Regosols located at the PUH during the summer of the study’s second year (2009). Among the crop species tested on Gleysols, the highest winter production was obtained from rye (16.3 t/ha) using CF while the highest summer production was obtained from sorghum (21.8 t/ha) using controlled release fertilizer (CF-A). Biomass yield of sorghum following application of SSF on Andosols with high fertility was 54.9 t/ha while the yield obtained through the mixing of Chemical Compound Fertilizer (CF-B) and SSF on Regosols was 33.2 t/ha. Application of SSF and BC improved soil fertility by increasing soil EC as well as soil carbon and nitrogen levels. SSF and BC proved to be effective, low-cost organic fertilizers. Gross calorific values for each energy crop were estimated at about 17.8 J/g. Assuming an average value of 16.7 J/dry Kg produced, total potential biomass in northern Hiroshima prefecture would have a calorific value of 670 MJ/ha.