Emergy comparison for different agro-ecological regions in Shanxi Province

Based on emergy methods, we compared and evaluated development situation, production efficiency and environmental loading of different agro-ecological regions in Shanxi Province. The results show that in the superior agro-ecological region, total emergy input and intensive degree (empower density = 1.67E+12 sej·m^-2) are high. However, human labor emergy is very high (labor emergy ratio = 70.62%) and nonrenewable industry supplemental emergy input is low, restricting labor emergy action in the region. Thus emergy yield ratio (EYR) is low (0.70) and environmental loading ratio (ELR) is high (9.33). One way to improve productive efficiency in the superior agro-ecological region is transferring superfluous labor from agriculture to other industries while increasing industry supplemental emergy input (especially high-tech industry supplemental emergy input). In the middlle agro-ecological region, the combination of labor emergy (labor emergy ratio = 51.67%) and industry supplemental emergy (industry supplemental emergy ratio = 23.36%) is better. Total emergy yield is high and so is EYR (1.25), showing a high agricultural production efficiency. However, it is still necessary to reinforce high-tech industry supplemental emergy input in order to further improve agro-ecosystem efficiency. In the inferior agro-ecological region, both total emergy yield and production efficiency are low since the environment is poor and productive methods are highly rough. If agricultural productive areas are rearrange in the region, including planting areas, forestry areas, livestock breeding areas, and fishing areas (with emphasis on dimension and concentrated production), agricultural production efficiency in the region may improve anew.