Mitsuhiko Katahira

Effects of Agricultural Machine Fuel Consumption on Paddy Fields

Recently, rice-growing farmers in Japan have confronted difficult conditions and decreasing market prices of rice. The Shonai area of Yamagata prefecture, which has many medium-scale cultivated fields, is among Japan’s largest rice cultivation areas. However, few studies have described the fuel consumption of agricultural machines in medium-scale paddy fields. Farmers in this area use some working systems, and fuel consumption can be reduced by changing the machine settings. Nevertheless, few studies have compared working systems related to fuel consumption. Therefore, the influence of different working systems (two methods for each of tillage, puddling and harvesting operations) on fuel consumption was investigated in medium-scale paddy fields. Working information for each agricultural machine was obtained using GPS logger attached to them. Fuel consumption was measured using a top fill method for each work test. The total work rates were 4.4 h/ha and 4.7 h/ha for method 1 and method 2 at tillage, 4.5 h/ha and 4.7 h/ha for method 3 and method 4 at puddling, respectively. Work rate was 4.0 h/ha for both method 5 and method 6 at harvesting (cutting width: 1,440 mm; work speed: 1.25 m/s and 1.35m/s). Results showed that the fuel consumptions were 23 L/ha and 26 L/ha for method 1 and method 2 at tillage, 17.2 L/h and 18.4 L/ha for method 3 and method 4 at puddling, and 30 L/ha and 28 L/ha for method 5 and method 6 at harvesting, respectively. These results showed no significant difference in fuel consumption between any working methods of rice cultivation. Tillage operation showed increased fuel consumption with higher working hours (included turn, back and other movements), higher total work time and also higher total distance. Puddling showed increased fuel consumption with higher working time that included turn and other movements. Harvesting operation showed increased fuel consumption as the total working time increased.

An Investigation into the Optimization of Rice Straw Collection System for Bioethanol Fuel Production from Reclaimed Heavy Clay Paddy-Rice Fields in Hachirogata

This investigation examined optimization of a rice straw collection system designed to produce bioethanol fuel from paddy-rice grown over 9800 ha in reclaimed heavy clay paddy-rice fields in Hachirogata, Japan. This study investigated agricultural machinery performance in various field conditions with different cutting lengths of rice straw. The rice straw collection system includes raking, packing, bale handling transportation, and wrapping to wrapping bale handling transportation. The operating speed was little affected by differences in cutting lengths by raking. Operating speeds were increased by packing with 20 cm blocks. Roll bale transportation using a bale handler achieved high operation speeds for 20 cm blocks, when holding roll bales. Raking, packing, and roll bale transportation improved the work rate for short cutting lengths of rice straw. The tendency was strongest for the 20 cm block. Specific fuel consumption was influenced by operation distances for raking, bale weight with packing, and by operation speed with roll bale transportation. After rice straw collection work, soil compression depths were 15.9 mm on average, and 39.4 mm at the maximum value. Each investigation plot had many iterations of tread pressure, which exacerbated soil compression. All investigated plots show large penetrated depths, as measured using a rectangular plate, indicating large soil compression depth with few tread pressure iterations.