Variability in environmental impacts during conversion from conventional to organic farming: a comparison among three rice production systems in Japan
Variability in environmental impacts during conversion from conventional to organic farming: a comparison among three rice production systems in Japan
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DOI：
10.1016/j.jclepro.2011.12.005
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发表时间：
2012-06-01
影响因子：
11.1
通讯作者：
Hayashi, Kiyotada
中科院分区：
文献类型：
--
作者：
Hokazono, Shingo;Hayashi, Kiyotada
早期将生命周期评估（LCA）应用于有机农业与传统农业的比较，假设农业生产的年变化可以忽略不计。虽然基于平均值的比较很重要，但由于有机农业在传统农业转化过程中的表现是不稳定的，因此有必要研究转化期间环境影响的变异性。在这项研究中，从一个为期五年的农场试验中获得的时间序列数据被应用于日本三种水稻生产系统的LCA：有机、环境友好和传统。采用全球变暖、酸化、富营养化和不可再生能源四个影响类别进行评估。结果表明，在所有影响类别中，只有与有机农业相关的环境影响多年来波动很大，而且这些波动随着时间的推移而减弱。在研究涵盖的四个类别中，有机水稻生产的环境影响平均高于其他两种水稻生产方式。然而，在转化阶段的最后阶段，它们下降到与传统耕作相同的水平。在初始阶段，有机农业的影响变异性较大的原因主要与有机水稻产量的不稳定性有关。研究结果表明，了解季节间变化趋势对有机农业的成功转型至关重要。(C) 2011 Elsevier Ltd.版权所有。
Earlier applications of the life cycle assessment (LCA) to organic agriculture concern comparisons with conventional agriculture under the assumption that year-to-year variations of agricultural production are negligible. Although the comparisons based on averages are important, it is necessary to investigate the variability in environmental impacts during the conversion period, because the performance of organic farming in the conversion process from conventional farming is unstable. In this study, time-series data obtained from a five-year on-farm trial were applied to an LCA of three rice production systems in Japan: organic, environmentally friendly, and conventional. Four impact categories global warming, acidification, eutrophication, and non-renewable energy were used for the assessment. The results showed that only the environmental impacts associated with organic farming fluctuated widely over the years across all impact categories, and these fluctuations diminished over time. The environmental impacts of organic rice production were higher than those of the other two modes of rice production in four categories covered in the study on average. However, they decreased to the same level as that of conventional farming in the last stage of the conversion phase. The cause of higher variability in the impacts of organic farming at the initial phase was associated mainly with the instability of the organic rice yield. The results indicate that understanding the trends in inter-temporal variability is important for successful conversion to organic farming. (C) 2011 Elsevier Ltd. All rights reserved.