Study on the role of weeds in the productivity improvement of “raising geese in corn field” system

In this study, the effects and status of weeds in the improvement of farmland productivity in the “raising geese in corn field” system were determined by analyzing and comparing the “raising geese in corn field” (GCF) treatment and conventional herbicide treatment (CK). The results showed that the weed diversity under GCF treatment was better than that under CK, and the weed yield was significantly higher than that under CK (P < 0.05). However, the presence of weeds seriously affected the growth of maize (Zea mays), and the leaf area of maize treated with GCF was significantly lower than that under CK before and after grazing (P < 0.01), directly leading to a maize yield reduction of 40.64%. The correlation analysis results showed that both weed yield and diversity were key factors that led to maize yield reduction; the R² values were −0.689 and −0.881, respectively, but as the number of geese eating weeds under GCF treatment reached 60.24 t·ha⁻¹, the comprehensive income under GCF treatment was still 137.11% higher than that under CK as the geese ate weeds and turned them into an economically viable product. Therefore, weeds play a vital role in the economic benefits from “raising geese in corn fields,” which indicates a new way for treating weeds in the future.