2018 Volume 34 Issue 2 Pages 29-40
In recent years, it is required to establish environmentally friendly agricultural production systems. In this study, environmental impacts of dairy production including different types of feed production systems were evaluated by Life Cycle Assessment method according to “Agricultural Production Technology Systems” created by Hokkaido and Iwate Prefecture. Four types of feed production (hay, low moisture herbage roll silage cutting three times annually, pasture, maize silage) in Hokkaido and two types of feed production (herbage roll silage cutting three times annually and maize silage) in Iwate were analyzed according to three types of fertilizer application (chemical fertilizer only, together with manure and together with slurry), respectively. These results were included into environmental impact assessment of dairy productions which consists of four types (40, 60,100 and 400 head size) of production systems in Hokkaido and 2 types (40 and 100 head size) in Iwate. Global warming load (GWL), acidification load (AL) and eutrophication load (EL) were evaluated. The results showed that the environmental impact of dairy production was lower in the types of organic fertilizer use, even though the impact of organic fertilizer use was higher in case of feed production. AL was higher in Iwate and EL was higher in Hokkaido while there was no significant difference in GWL. Large scale production systems had lower environmental impact. The result of integrated environmental impact potential by LIME2 (Life cycle Impact assessment Method based on Endpoint modeling 2) showed that the AL by ammonia had the highest contribution in economic damage amount. As a consequence, the results suggest that the selection of organic fertilizer in feed production in order to contribute to the utilization of animal excrements and the effective production systems by the efficient machinery use will contribute to the reduction of environmental impact in dairy production.
