Measuring the environmental effects of organic farming: A meta-analysis of structural variables in empirical research

Abstract

This study examined the structural variables affecting the environmental effects of organic farming compared to those of conventional farming. A meta-analysis based on 107 studies and 360 observations published from 1977 to 2012 compared energy efficiency (EE) and greenhouse gas emissions (GHGE) for organic and conventional farming. The meta-analysis systematically analyzed the results of earlier comparative studies and used logistic regression to identify the structural variables that contributed to differences in the effects of organic and conventional farming on the environment. The statistical evidence identified characteristics that differentiated the environmental effects of organic and conventional farming, which is controversial. The results indicated that data sources, sample size and product type significantly affected EE, whereas product type, cropping pattern and measurement unit significantly affected the GHGE of organic farming compared to conventional farming. Superior effects of organic farming on the environment were more likely to appear for larger samples, primary data rather than secondary data, monocropping rather than multicropping, and crops other than fruits and vegetables. The environmental effects of organic farming were not affected by the study period, geographic location, farm size, cropping pattern, or measurement method.

Many shades of gray—The context-dependent performance of organic agriculture

“…Lee et al ( 58 ) found that the benefit of organic management in terms of energy consumption is lowest for vegetables and fruits, whereas the benefit in terms of GHG emissions was higher in monocropping systems (Table 1). …”

Using Digestate and Biochar as Fertilizers to Improve Processing Tomato Production Sustainability

“…Different works also reported that the agrosystem biodiversity is improved in the OFS [5,7,8]. In addition, synthetic pesticides and fertilizers are not allowed, and there is a reduction of nitrate leaching and greenhouse gas emissions in comparison with the conventional farming system [3,8,9]. However, since the OFS has lower land-use efficiency than the conventional system, these positive effects are less pronounced and in sometime reversed when expressed per unit product [9,10].…”

To be or not to be for humankind - organic diets revisited for a sustainable development

“…The studies performed so far often show that the environmental impact of organic food systems is smaller than the impact of conventional food systems when expressed per area land [11]. There is still debate regarding the question whether this also applies when expressed per kg crop, as the crop yield of organic food systems is usually lower than that of conventional food systems [9,11] and the context might play an important role [17]. A very recent meta-analysis of a high number of life cycle assessments revealed that per unit food, organic systems require more land and cause more eutrophication [3].…”