Resolving inconsistencies in environmental impact assessments of organic farming: a comparison of two meta-analyses.

Abstract

CONTEXT: In the midst of the growing popularity of organic farming, persistent questions surround its environmental effects. A 2017 meta-analysis suggested elevated acidification and eutrophication potentials per land area for organic farming relative to conventional farming, influencing policy and individual choices. However, a recent 2023 meta-analysis contradicted these findings, revealing reduced or comparable impacts across various environmental indicators, including acidification and eutrophication potentials. OBJECTIVE: These discrepant findings from these studies highlight the need for a comprehensive understanding of the underlying causes and implications. This study seeks to unravel the source of these disparities. METHODS: Initially, we scrutinized whether the differences in findings could be attributed to variations in the agricultural products selected for analysis. Subsequently, we explored the possibility that disparities were influenced by distinct averaging methods employed in the two studies. To address the impact of sample size, our investigation considered whether differences in findings could be attributed to varying sample sizes. RESULTS AND CONCLUSIONS: This study reveals that the disparities between these meta-analyses stem from differences in averaging methods and sample sizes. The 2023 meta-analysis, employing a more robust averaging method and a larger sample size, emerges as a more reliable source of information. Researchers are encouraged to incorporate the 2023 findings into their investigations, potentially necessitating a reconsideration of agricultural policies and dietary choices to align with updated environmental impact assessments. SIGNIFICANCE: By resolving inconsistencies in environmental impact assessments of organic farming, this study facilitates more effective societal and individual decision-making for greater sustainability.