A Sustainability Analysis of Two Rapeseed Farming Ecosystems in Khorramabad, Iran Based on Emergy and Economic Analyses.

In the past two decades, rapeseed farming has garnered attention, because it offers the possibility of attaining self-sufficiency in the production of edible oil, which is a strategic product for Iran. Therefore, the overarching goal of this research was to provide sound strategies to further the development of rapeseed farming and to increase the sustainability and productivity of rapeseed production systems. Progress toward this goal was made by assessing subsistence and commercial rapeseed production systems in Khorramabad, Iran during the 2017-2018 crop year using both emergy and economic indices. The calculated values of the ESI*, %R, ELR, and ELR* indices showed the higher ecological sustainability of the subsistence farming system compared to the commercial system of rapeseed production. According to these indices, the main reason for the lower sustainability of the commercial rapeseed production system was the large amount of soil organic matter that was lost per unit input of nonrenewable resources used. A large emergy exchange ratio in favor of the buyer, the increased environmental sustainability when the market impact is considered, the lower emergy consumption per unit of output, and the higher productivity of the production factors all reflect the relative advantage of the commercial system based on the indices of EER, EISD, UEV, and total factor productivity (TFP), respectively. Hence, our findings revealed that in the commercial rapeseed production system, the ecologic sustainability of the system can be improved drastically by employing scientific solutions for the comprehensive management of the production ecosystems, especially through the amelioration of soil organic matter and prevention of its loss. Besides improving the farmers' technical knowledge, the integration of small lots into the production system is recommended for improving the economic sustainability of the subsistence production system.