An Engineering Intervention to Prevent Paddy Straw Burning Through In Situ Microbial Degradation

Abstract

The study intended to design, develop and evaluate mechanical interface on the basis of physical, engineering and mechanical properties of paddy straw for size reduction. The mechanical interface comprised of loose straw collector, stalk chopper, conveyor, applicator and discharging unit. A 300 L plastic cistern containing fungal inoculum dose prepared from Aspergillus nidulans, Aspergillus awamori, Phanerochaete chryosporium and Trichoderma viride was installed to apply the fungal inoculum uniformly @1000 g per 1000 kg of the chopped straw. The chopped straw was subjected to degradation in rectangular strips with and without inoculant overhead and rotavator incorporated with soil. The treated straw assimilated with the soil bolstered the nitrogen content to 182.0 kg ha⁻¹, phosphorus 63.5 kg ha⁻¹, potassium 1862.5 kg ha⁻¹ and organic carbon 0.51% from initial value of 110.6 kg ha⁻¹, 42.8 kg ha⁻¹, 1068.4 kg ha⁻¹ and 0.33%, respectively. In S₃, the soil–straw–microbe interaction provided feasible conditions for the microbial growth, depicted from 53.5% upsurge in dehydrogenase activity to 111.04 µg TPF g⁻¹ per 24 h. The surge in microbial growth coincided with the 16.8% increase in biomass consumption and releasing of CO₂ from 272.8 to 319.1 milligram within first phase of degradation. The rapid growth of the microbes at the initial stage decreased the moisture and resources essential for sustaining the growth. In the final stage, the dehydrogenase activity and biomass content decreased 6% to 105.04 µg TPF g⁻¹ per 24 h and 23.7%, decreasing the emission of carbon dioxide to 307.1 mg within 45 days degradation period. The variation in the emission at the last stage can serve as ammunition to fight carbon dioxide induced global climate change.