Short-term nickel residual effect in field-grown soybeans: nickel-enriched soil acidity amendments promote plant growth and safe soil nickel levels

Nickel-enriched soil acidity amendments (SAA) may be advantageous for neutralizing acidity and providing safe/uniform distribution of Ni in soils. We evaluated the short-term effects of Ni application on field-grown soybean yield, growth, and soil chemical attributes using three sources of SAA, two enriched with Ni (Ni-rich mining by-product and Ni-salt) and a commercial SAA. The tested Ni-enriched sources were effective in providing Ni to the soil at safe levels, neutralizing acidity and increasing base saturation. A one-time Ni application resulted in optimal Ni levels in the first cropping season, enhancing grain yield by up to 658 kg ha(-1) and improving nitrogen metabolism in soybean. A low residual effect of Ni was observed in the second year, with soil available Ni and plant Ni concentrations decreasing to sub-optimal levels and yield gains not being observed. In conclusion, the application of Ni-enriched SAA is a sustainable technology for agriculture, optimizing soil management practices. The SAA derived from by-products has benefits to the mining sector, meeting the 'Ensure Sustainable Consumption and Production Patterns' (SDG 12). Our findings suggest that this micronutrient may require a year-to-year adjustment via Ni-fertilization and the total Ni concentration in the soil should be monitored over the cropping seasons.

Automated summary

The study found that nickel-enriched soil acidity amendments can have short-term positive effects on soybean yield and growth, but the efficacy of nickel decreases in the second year. By adjusting nickel fertilization, crop yield and base saturation can be improved, optimizing soil management practices over time.