Sustainability Evaluation of the Maize–Soybean Intercropping System and Maize Monocropping System in the North China Plain Based on Field Experiments

Abstract

Monocropping systems, which currently dominate China’s major grain production regions, contribute to resource scarcity and environmental pollution. Intercropping has the potential to improve resource use efficiency. However, prior studies of intercropping systems have generally focused on ecological, economic, and social consequences. Here, we make a comparative ecological sustainability analysis on energy capture and efficiency of maize monocropping and maize–soybean intercropping systems through emergy evaluation based on field experiments performed from 2012 to 2014. We find that maize monocropping shows higher sustainability than maize–soybean intercropping in the North China Plain at present. Quantitative results indicate that for maize monocropping, the emergy yield ratio (EYR) and emergy sustainability index (ESI) are 13.7% and 21.1% higher than that of intercropping systems, and the environmental loading ratio (ELR) is 7.3% lower than that of intercropping systems. To further test, we applied three levels of nitrogen fertilizer in intercropping systems (120 kg ha−1, 180 kg ha−1, 240 kg ha−1), and find that a reduced rate of N fertilizer for intercropped system leads to higher sustainability (ESI 5.3% higher) but still lower sustainability than maize monocropping. Key drivers of the different sustainability outcomes are decreased energy output and a larger proportion of labor input associated with intercropping systems.

Assessment of biofertilizer use for sustainable agriculture in the Great Mekong Region

“…China and Vietnam have recorded the highest levels of chemical fertilizer inputs in the region (Table 2). Chinese farmers have applied up to 600 kg ha −1 per year of mineral fertilizers over the last couple of decades (Yang et al, 2018), and currently apply approximately 70% more chemical inputs to their crops as compared to the rest of the world (Times, 2017). Vietnam is also in a similar situation where the demand and use of fertilizers is very high for over 10 million ha of agricultural land.…”

Crop Diversity and Resilience to Droughts: Evidence from Indian Agriculture

“…However, monoculture could also lead to long-term negative impacts, posing challenges to the sustainability of the food system since it is resource intensive. Despite crop intensification providing better yield than diversification, during the non-drought years, intensification cannot be advocated as a coping strategy since it involves the indiscriminate use of chemical inputs and leads to resource scarcity and environmental pollution (Yang et al, 2018). A decrease in diversity levels below the threshold could potentially limit the resilience of the food production system.…”

Assessment of nitrogen fertilization in cotton/soybean intercropping using the 15N isotope dilution method

“…However, intercropping can have negative effects on crops and environment. Previous studies have found that intercropping led to changes in crop morphology, reduced lodging resistance (Liu et al, 2016(Liu et al, , 2017 and higher labour costs (Hu et al, 2014;Yang et al, 2018). Formulating optimal intercropping systems is required for agricultural security and sustainable development.…”