Department of Agricultural Machinery Engineering, Faculty of Agricultural, Engineering and Technology, University of Tehran, Karaj, Iran.
Department of Agricultural Machinery Engineering, Faculty of Agricultural, Engineering and Technology, University of Tehran, Karaj, Iran; Environmental Specialist Research Team (ESRTeam), Tehran, Iran.
Sci Total Environ. 2016 Aug 15;562:614-627. doi: 10.1016/j.scitotenv.2016.04.070. Epub 2016 Apr 22.
Agro-food systems play a significant role in the economies of all nations due to energy use and the resulting environmental consequences. The sustainability of these systems is determined by a multitude of interacting economic, social and environmental factors. Dairy production presents a relevant example of the sustainability trade-offs that occur within such systems. On the one hand, dairy production constitutes an important part of the human diet, but it is also responsible for significant emissions of potent greenhouse gases and other pollutants. In this study, the environmental aspects of pasteurized milk production in Iran were investigated using a life-cycle approach. Three sub-systems, namely feed production, dairy farm and dairy factory, were taken into account to determine how and where Iranian pasteurized milk production might be made more environmentally friendly and energy efficient. The results clearly demonstrate that the feed production stage was the hot spot in pasteurized milk production in terms of energy consumption, environmental burdens and economic costs. The largest share of the total production costs belonged to animal feeds (43%), which were part of the feed production stage. The largest consumers of energy in the production of raw milk were alfalfa (30.3%), concentrate (24%), straw (17.8%) and maize (10.9%) for cows, followed by diesel fuel (6.6%) and electricity (5.6%). The global warming potential for the production of 1000kg of raw milk at the dairy-farm gate was estimated at 457kg CO2,eq. Thus, more than 69% of the total impact at the milk-processing gate resulted from the previous two sub-systems (feed production and dairy farm), with the feed-production stage accounting for the largest fractions of the environmental burdens.
由于能源利用和由此产生的环境后果，农业食品系统在所有国家的经济中都发挥着重要作用。这些系统的可持续性取决于众多相互作用的经济、社会和环境因素。乳制品生产是这些系统中出现可持续性权衡的一个相关例子。一方面，乳制品生产构成了人类饮食的重要组成部分，但它也是导致大量强温室气体和其他污染物排放的原因。在本研究中，采用生命周期方法研究了伊朗巴氏奶生产的环境方面。考虑了三个子系统，即饲料生产、奶牛场和乳品厂，以确定如何以及在何处可以使伊朗巴氏奶生产更环保和节能。结果清楚地表明，在能源消耗、环境负担和经济成本方面，饲料生产阶段是巴氏奶生产的热点。总生产成本的最大份额属于饲料生产阶段的动物饲料（43%）。在生奶生产过程中，苜蓿（30.3%）、浓缩饲料（24%）、秸秆（17.8%）和玉米（10.9%）是奶牛消耗能量最多的饲料，其次是柴油燃料（6.6%）和电力（5.6%）。在奶牛场门口生产 1000 公斤生奶的全球变暖潜势估计为 457 公斤 CO2eq。因此，在奶制品加工门口的总影响中，超过 69%来自前两个子系统（饲料生产和奶牛场），其中饲料生产阶段占环境负担的最大部分。
