Manipulation of nitrogen leaching from tea field soil using a Trichoderma viride biofertilizer

Abstract

With the increasing use of chemical fertilizers, negative environmental impacts have greatly increased as a result from agricultural fields. The fungus Trichoderma viride used as a biofertilizer can efficiently reduce nitrous oxide (N₂O) emissions from subtropical tea fields in southern China. In this paper, it was further found that T. viride biofertilizer could alleviate nitrogen (N) leaching in tea fields. Gross N leaching was 1.51 kg ha⁻¹ year⁻¹ with no external fertilizer input, but when 225 kg N ha⁻¹ year⁻¹was applied, it increased to 12.38 kg ha⁻¹ year⁻¹ using T. viride biofertilizer but 53.46 kg ha⁻¹ year⁻¹ using urea. Stepwise linear regression analysis identified the factors responsible for N leaching to be soil nitrate concentration and soil interflow, simulated here using the water balance simulation model (WaSiM-ETH). Finally, mass-scale production of T. viride biofertilizer from waste reutilization using sweet potato starch wastewater and rice straw was found to be cost-effective and feasible. These procedures could be considered a best management practice to reduce N leaching from tea fields in subtropical areas of central China and to reduce pollution from other agricultural waste products.