Abstract:
Objective The aims were to Clarify the impacts of indigenous soil productivity on the agronomic and environmental benefits responses to chemical fertilizers application in spring maize production, in order to provide a basis for soil fertility improvement and sustainable production in the maize-producing regions of Northeast China.
Method Based on 680 field experiments conducted in Jilin Province from 2005 to 2013, the treatments, including no fertilization (CK), nitrogen-phosphorus-potassium application (NPK), no nitrogen (-N), no phosphorus (-P), and no potassium (-K), were selected. The CK yield was used as the standard for classifying indigenous soil productivity to investigate the variation in maize yield, fertilization effects, nutrient use efficiency, and environmental benefits under different levels of indigenous soil productivity.
Result The maize yield of NPK treatment showed a continuous upward trend with the increase in indigenous soil productivity. For every 1 t hm−2 increase in indigenous soil productivity, maize yield of NPK treatment increased by 0.73 t hm−2. Meanwhile, an improvement in indigenous soil productivity also significantly enhanced the contribution rate of soil productivity to the yield, while the contribution rate of fertilizers to the yield and the agronomic efficiency of fertilization gradually decreased. Boundary line analysis indicated that when indigenous soil productivity reached 7.87 t hm−2, the maize yield of NPK treatment could achieve a maximum yield of 15.9 t hm−2. Enhancing indigenous soil productivity reduced the gap between yield of NPK treatment and maximum yield, improving yield stability and sustainability. In terms of environmental benefits, for maize production under the NPK treatment, total reactive nitrogen loss per unit area and eutrophication potential value decreased with increasing indigenous soil productivity, whereas greenhouse gas emissions initially increased and then declined, and acidification potential value gradually intensified. Indigenous soil productivity exhibited a significant negative correlation with environmental footprint and intensity based on unit maize yield. For every 1 t hm−2 increase in indigenous soil productivity, nitrogen footprint, carbon footprint, eutrophication intensity, and acidification intensity decreased by 0.57 kg N t−1, 19.88 kg CO2 eq t−1, 0.24 kg PO4 eq t−1, and 0.57 kg SO2 eq t−1, respectively.
Conclusion Enhancing indigenous soil productivity promotes high and stable yields of maize under balanced fertilization conditions, while simultaneously achieving emission reduction and efficiency improvement. It is recommended to further improve the soil and boost its basic productivity through measures such as rational tillage and optimized fertilization, thus providing crucial support for the coordinated realization of increasing spring maize yield and sustainable production.