Xi Yunguan, Qin Pei
School of Life Science, Nanjing University, Nanjing 210093, China.
Ying Yong Sheng Tai Xue Bao. 2006 Feb;17(2):237-42.
Employing emergy value evaluation method, this paper compared the ecological and economic benefits of rice-duck organic farming system (mode I) and conventional rice-wheat rotation system (mode II) in Shanghai suburb. The results showed that mode I had better emergy benefits, higher self-organizing ability and sustainability, and higher product safety. The net emergy yield ratio (EYR), feedback ratio of yield emergy (FYE), and emergy sustainable index (ESI) of mode I were respectively 1.57, 14.1, and 8.71 times as much as those of mode II, and the emergy index of product safety (EIPS) was 0 in mode I but -0.66 in mode II. The emergy investment ratio (EIR) and environmental loading ratio (ELR) of mode I were 40.1% and 18.3% of mode II, respectively, suggesting that mode I had less environmental pressure than mode II. Mode I had lower economic benefits than mode II. The economic output, gross income, and net income of mode I were 15.7%, 9.6%, and 29.6% less than those of mode II , respectively. As for Em dollars, the output, gross income, and net income of mode I were respectively 50%, 102.6%, and 136.4% higher than those of mode II. With the system optimization and the development of organic food market, mode I had the potential to improve its economic benefits.
运用能值评价方法，本文比较了上海郊区稻鸭有机种植系统（模式I）和传统稻麦轮作系统（模式II）的生态和经济效益。结果表明，模式I具有更好的能值效益、更高的自组织能力和可持续性，以及更高的产品安全性。模式I的净能值产出率（EYR）、产出能值反馈率（FYE）和能值可持续指数（ESI）分别是模式II的1.57倍、14.1倍和8.71倍，模式I的产品安全能值指数（EIPS）为0，而模式II为-0.66。模式I的能值投资率（EIR）和环境负载率（ELR）分别是模式II的40.1%和18.3%，表明模式I的环境压力小于模式II。模式I的经济效益低于模式II。模式I的经济产出、总收入和净收入分别比模式II少15.7%、9.6%和29.6%。以能值美元计，模式I的产出、总收入和净收入分别比模式II高50%、102.6%和136.4%。随着系统优化和有机食品市场的发展，模式I有提高其经济效益的潜力。
