Comprehensive evaluation of eco-economic benefits of multi-crop rotation in paddy field systems

The study aimed to build sustainable application of evaluation index systems and methods and to select sustainable rotation patterns of multi-cropping with high efficiency green in the Poyang Lake Eco-Economic Zone. We conducted two consecutive years of field experiment and used a comprehensive index method to evaluate ecological and economic benefits of different rotation patterns of multi-cropping system in paddy fields. Based on the price of late rice, the results showed that crop yield of vegetables-sugar cane||soybean was the highest, followed by that of milk vetch-early rice-late rice and that of faba bean-early rice-sweet potato||maize the lowest. In 2012, the order of the overall efficiency index was vegetables-sugar cane||soybean > rapeseed-maize||soybean-late rice > faba bean-early rice-sweet potato||maize > milk vetch-early rice-late rice > winter fallow-early rice-late rice. This suggested that ‘vegetable-sugar cane||soybean’ intercropping pattern made rice production more economical as paddy fields supported high-yields with high efficiency. It was conducive for sustainable development of agricultural production. After multi-crop rotation, the order of the overall efficiency index for 2013 was milk vetch-early rice-late rice > vegetables-sugar cane||soybean > rapeseed-maize||soybean-late rice > faba bean-early rice-sweet potato||maize > winter fallow-early rice-late rice. The ‘milk vetch-early rice-late rice’ cropping pattern well accounted for the three main benefits conducive for sustainable agricultural production. Based on comprehensive benefits of the two-year experimental results, ‘vegetables-sugar cane||soybean → milk vetch-rice-rice’ cropping pattern had the highest efficiency and yield. It well accounted for social, ecological and economic benefits, favorable for food security and structural agricultural adjustment that in turn increased farmers’ income and other socio-economic benefits. It was also critical for the promotion of agricultural development in winter, making full use of natural resources that resulted in sustainable agricultural production. In a conclusion, ‘vegetables-sugar cane||soybean → milk vetch-early rice-late rice’ was the best rotation pattern for winter agriculture and multi-crop rotation system in terms of the scale of application in paddy fields in Poyang Lake Eco-Economic Zone.