Comparison of resources use efficiencies among paddy-upland multi-crop rotation systems in the middle reaches of Yangtze River

A field experiment was conducted to search for the possibility of efficient use of farmland resources, maintain virtuous circle of agricultural ecology and optimize traditional planting patterns in the middle reaches of Yangtze River. The use efficiencies of solar radiation, heat, water and land in 5 paddy-upland multi-crop rotation systems (winter fallow-early rice-late rice → winter fallow-early rice-late rice, potato-maize soybean ‖ -late rice → vegetable-peanut corn ‖ -late rice, vegetable-peanut corn ‖ -late rice → green manure-early rice-late rice, milk vetch-early rice-late rice → rapeseed-peanut-late rice, rapeseed-peanut-late rice → potato-maize‖ soybean-late rice) with continuous cropping with winter fallow as the control were analyzed. Results showed that solar radiation use efficiency in winter, late season and for the year under paddy-upland multi-cropping rotation patterns was higher than continuous cropping with winter fallow. Annual solar radiation use efficiency was respectively 8.26%-82.50% and 2.63%-121.42% higher than continuous winter fallow during the two years. Vegetable-peanut corn ‖ -late rice → green manure-early rice-late rice pattern had the highest solar radiation use efficiency in winter, spring and in the whole year. Annual effective accumulated temperature utilization rate of paddy-upland multi-cropping rotation patterns was higher than that of continuous cropping with winter fallow, which were respectively 12.87%-21.26% and 11.17%-25.88% higher than continuous cropping with winter fallow during the two years. Vegetable-peanut corn ‖ -late rice → green manure-early rice-late rice pattern was the best among all patterns. Water use efficiency in winter, late season and for the year under paddy-upland multi-cropping rotation patterns was higher than that of continuous cropping with winter fallow, with annual water use efficiencies respectively 45.36%-83.50% and 40.00%-118.75% higher during the two years. Potato-maize soybean ‖ -late rice → vegetable-peanut corn ‖ -late rice pattern was best in late season and annual year. Vegetable-peanut corn ‖ -late rice → green manure-early rice-late rice was the highest in winter. Land use efficiency of green manure-early rice-late rice rotation pattern was the highest, with an average utilization rate of 96.11%. Land use efficiency of vegetable-peanut maize ‖ -late rice → green manure-early rice-late rice multi-cropping pattern was the highest. Comprehensive analysis showed that annual solar radiation use efficiency, annual effective accumulated temperature utilization rate, water use efficiency and land use efficiency under paddy-upland multi-cropping rotation patterns were higher than that under continuous cropping with winter fallow. Vegetable-peanut corn ‖ -late rice → green manure-early rice-late rice, and milk vetch-early rice-late rice → rapeseed-peanut-late rice performed better and thus suitable for promotion in the middle reaches of Yangtze River.