Life Cycle Assessment of Dairy Production Systems Including Material Cycles of Grasslands

与奶牛场相关的环境问题不仅是水污染、异味等地方性问题，而且是全球变暖、酸化等全球性问题。对奶牛场的环境问题进行量化是奶牛场环境信息披露的必要条件。在本研究中，我们使用LCA（生命周期评估）来量化它们。LCA研究产品从原材料获取到生产、使用和处置的整个生命周期（即从摇篮到坟墓）的环境因素和潜在影响（ISO14040）。我们选择Okoppe饲料服务公司（OFS）和参与OFS的8家奶牛场进行研究。OFS的主要作用是有效生产饲料和生产TMR（总混合日粮）。我们于2002年7月实地调查了OFS和奶牛场，并收集了2001年LCA的资料。LCA的奶业系统由OFS和奶牛场组成。利用孕产妇数据和排放因子对环境负担CO2、CH4、N2O、NOx、SOx、NH3、T-N酸T-P进行量化。每种环境负担都与全球变暖潜势（CO2、CH4和N2O）、酸化（NOx、SOx和NH3）和富营养化（NOx、NH3、T-N和T-P）等环境问题有关。使用LCA结果，我们确定了本研究中乳制品系统中具有最大环境影响（热点）的参数。与奶牛场有关的问题显示为追随者；首先，牲畜棚内牲畜排放的CH4和排泄物处理设施（尤其是堆肥仓）粪便排放的N2O有可能导致全球变暖。第二，酸化是由畜舍和粪便处理设施（特别是堆肥仓）排泄物中的NH3引起的。富营养化是由堆肥仓排泄物中的T-N和T-P引起的。

The environmental problems associated with dairy farms are not only local problems such as water pollution and offensive odor, but also global problems including global warming and acidification. Quantifying dairy farm's environmental problems is necessary for the disclosure of the environmental information of dairy farms. In this study, we use LCA (Life Cycle Assessment) to quantify them. LCA studies the environmental aspects and potential impacts throughout a product's life (i.e. cradle-to-grave) from raw material acquisition through to its production, use and disposal (ISO14040). We have selected Okoppe Feed Service (OFS) arid eight dairy farms, which participate in OFS for this study. The main roles of OFS are the efficient production of forage and the production of TMR (Total Mixed Ration). We investigated OFS and the dairy farms in the field in July 2002, and collected the material data of year 2001 for LCA. The dairy system of LCA is composed of OFS and the dairy farms. Environmental burdens, which are CO2, CH4, N2O, NOx, SOx, NH3, T-N acid T-P, are quantified using the maternal data and emission factors. Each environmental burden is related to environmental problems, which are global warming potential (CO2, CH4 and N2O), acidification (NOx, SOx and NH3) and eutrophication (NOx, NH3, T-N and T-P). We identify the parameters, which have the largest environmental impact (hot-spots) in the dairy system of this study, using the LCA results. The problems related to dairy farms are shown as followers ; First, there is the potential for global warming are as a result of CH4 from livestock in animal houses and N2O from manure in excreta-processing facilities (especially compost barns). Second, acidification is caused by NH3 from excreta in animal houses and excreta-processing facilities (especially compost barns). Third, eutrophication is resulting from T-N and T-P in compost barns excreta.