Trade-offs between productivity, economic benefits, and environmental sustainability of vegetable-rice rotation system in the tropics

This is the authors' abstract. We don't add key points for this paper.

• Increased cropping intensity improved productivity without economic benefits • Vegetables rotations increased environmental costs while results economic benefit • Optimizing fertilization is key to achieving sustainability in rice-vegetable rotation Multiple cropping is a widely adopted land management strategy to improve agricultural productivity. However, the environmental costs and agricultural sustainability of various rice cropping system remains unclear, particularly in tropical regions. Here, we evaluated the productivity, economic benefits, and environmental sustainability of contrasting rotations including pepper-rice-rice, cowpea-rice-rice, and bitter gourd-rice-rice as triple cropping, and pepper-single rice, cowpea-single rice, bitter gourd-single rice, and fallow-rice-rice as double cropping. The economic benefits of bitter gourd-single rice, and cowpea-single rice was higher than bitter gourd-rice-rice, and cowpea-rice-rice by 34.2%and 4.6%, respectively. The environmental footprint indexes of the bitter gourd-rice-rice based on unit farmland area and economic benefit was 17.1-40.7% lower than bitter gourd-single rice. Similarly, the environmental footprint index of per area and per economic of cowpea-single rice decreased compared to cowpea-rice-rice by 25.6 and 21.3%, respectively. These results indicate that reducing cropping intensity leads to lower environmental costs and higher economic benefits. In addition, nitrogen and phosphorus footprints were found to be the dominant contributors to the overall environmental costs. Meanwhile, optimizing fertilization and strategically arranging crop growth period are the key factors in improving the sustainability and productivity of the rotation systems. In conclusion, bitter gourd-single rice and cowpea-single rice rotations are recommended as optimal cropping systems in tropical regions to reduce environmental impacts while maintaining high yields and economic benefits.