Sustainable management of crop residues through composting and biochar production in rice-wheat zone

Abstract

Imagine a rice-wheat farmer in New York’s Finger Lakes region staring at 8 tonnes of straw per hectare after harvest, knowing that incorporation alone won’t solve the nitrogen tie-up problem. This research compared five residue conversion technologies—raw incorporation, windrow composting, vermicomposting, low-temperature biochar (300°C), and high-temperature biochar (500°C)—for their effects on product quality, soil amendment value, and economic feasibility over three years (2020-2023) at Cornell’s Musgrave Research Farm. Vermicomposting produced the highest-quality amendment (C:N ratio 14.7, N content 1.93%), while high-temperature biochar maximised carbon stability (67.3% C, half-life >1000 years). Cost-benefit analysis showed vermicomposting breaking even at year 2 and biochar at year 4.