In the dry sloping farmland areas of southern China, sugarcane—an important cash crop—has long faced the challenge of soil degradation. Due to topographical constraints and the influence of traditional monocropping systems, these regions commonly experience intensified soil erosion, nutrient imbalance, and a decline in microbial diversity. These issues threaten the stability of sugarcane yields and restrict the sustainable development of agriculture. The key question, therefore, is: how can soil health be improved while ensuring stable sugar production?
Recently, Guoqin Huang from Jiangxi Agricultural University and Kai Huang from Guangxi Hydraulic Research Institute systematically reviewed the multiple benefits of sugarcane intercropping in optimizing soil fertility. Their findings offer new insights for ecological restoration of dry sloping farmland in southern China. The related paper has been published in Frontiers of Agricultural Science and Engineering (DOI: 10.15302/J-FASE-2025612).
Traditional sugarcane cultivation often relies on monoculture with a single variety grown over large areas, which, over time, easily leads to soil compaction and nutrient loss. Intercropping—planting two or more crop species simultaneously in sugarcane fields—forms a natural soil restoration system. This approach improves soil quality mainly through three pathways: (1) Root system complementarity – Roots of different crops penetrate to various depths, effectively breaking up compacted soil and increasing soil porosity. (2) Nutrient complementarity – Intercropping enhances soil fertility by allowing crops to complement each other in nutrient use. Legumes, for instance, can form symbiotic relationships with rhizobia to fix atmospheric nitrogen, effectively fertilizing the soil at no cost. Meanwhile, crops such as maize and vegetables, with different nutrient uptake patterns, help reduce the need for chemical fertilizers. (3) Microbial diversity enhancement – Intercropping enriches soil microbial communities. Diverse root exudates and crop residues provide abundant food sources for beneficial microorganisms such as bacteria and fungi, promoting their proliferation.
By reviewing recent practical cases in southern China, the study found that sugarcane intercropping has expanded from early combinations with legumes to include maize, vegetables, green manure crops, and more. For example, in Guangxi’s sugarcane-growing areas, a “sugarcane–soybean” wide–narrow row planting system is used: soybeans are planted in the wide rows, making full use of available light while fixing nitrogen to benefit sugarcane growth. These models not only improve land use efficiency but also return crop residues to the soil, increasing organic matter content and creating a virtuous cycle.
It is worth noting that intercropping is not simply the physical addition of crops; it requires precise agronomic management. This includes adjusting row spacing and controlling crop proportions to avoid competition for light and nutrients, as well as selecting crop varieties with compatible growth periods to ensure normal development of both species.
Despite the significant benefits of intercropping, its promotion still faces challenges. The paper highlights three major bottlenecks to be addressed in the future: (1) Developing intercropping techniques compatible with mechanized operations, particularly to suit small-scale agricultural machinery in southern hilly and sloping areas. (2) Establishing regional intercropping model databases to recommend optimal crop combinations for different climates and soil types. (3) Strengthening policy support through subsidies, technical training, and other measures to enhance farmers’ willingness to adopt the practice.
DOI: 10.15302/J-FASE-2025612