Efficiency analysis of organic farming systems- a review of methods, topics, results, and conclusions

The article summarizes the literature on efficiency and productivity of organic farming. A short overview on theories and models is provided. We can distinguish between studies that concentrate of specific problems of the organic sector and studies that aim to compare conventional and organic farming systems. Sample selection is a major challenge for comparisons between organic and conventional farms, since the organic farms have a different farm-structure and are often represented by a relatively small number of observations. We find that conversion to organic farming is influenced by inefficiency. In three of four studies, organic farms have a lower productivity than conventional farms. Studies on environmental efficiency document that organic farming show a higher degree of efficiency if environmental variables (such as landscape elements and diversity in the croprotation) are taken into account. The impact of subsidies on farm efficiency is often found to be negative.