Preliminary analysis on economic and environmental consequences of grain production on different farm sizes in North China Plain

Due to rapid economic growth and dramatic urbanization in China in the recent 30 years, the traditional model for grain production dominated by small-size household farms is gradually being broken, while large-scale farming is becoming increasingly common. However, the information on relationships of environmental and economic consequences of grain production on different farm size has been lacking. In this study, life cycle assessment and economic analysis are used to compare environmental and economic performance of wheat-maize double-cropping system on small, medium and large farm size in North China Plain (NCP). The life cycle assessment indicates that, compared to the small-farm, area-based environmental impact index (EIA) is decreased by 2.4% and 3.4% for the medium-farm and large-farm, yield-based environmental impact index (EIY) is increased by 14.3% for the medium-farm while decreased by 3.4% for the large-farm. The economic analysis shows that the yield-based profits (EPY) for the medium-farm and large-farm are 83.4% and 71.7% lower than that for the small-size farms but the expansion of farm size contributes to the improvement of incomes of workers and owners of the farms together. Generally, the potential environmental impacts of grain production on the same area farmland will possibly change due to the difference of farm size, but expanding farm size will not directly and obviously improve the potential environmental consequences of grain production in the NCP. The larger size farm earns the more net income annually, but the conventional small-farm has the better revenue at the point of yield-based profit. Moreover, a scenario analysis represented that the EIY and EPY for the medium-farm and large-farm would be improved by 1.1%-47.1% and by 11.1-267.3%, respectively, by improved fertilization, irrigation and machines practices. Clearly, the advanced agricultural practice is the key point to improve the environmental and economic consequences for grain production in the NCP. Therefore, it is not scientific to only emphasize the expansion of farm size but, meanwhile, not to promote the implementation of advanced agricultural practices for the environmental and economic consequences of grain production in the NCP.