Integrated Nutrient Management: An Effective Strategy to Mitigate Greenhouse Gas Emission and Global Warming Potential Under Rice Cultivation

Abstract

Nutrient management practices in rice cultivation have a profound impact on the emission of greenhouse gases, especially methane (CH₄) and nitrous oxide (N₂O). Practices involving amendment of different kinds of substrate constituting organic waste have gained momentum in finding measures to reduce the emission of CH₄and N₂O from rice fields. A field experiment was conducted for two years consecutively in rice field to measure emission of CH₄ and N₂O under the treatment of different kinds of composts, along with their combination with chemical fertilizer. A short-duration rice variety, RC Maniphou 12 (RCM 13) was cultivated inrainfed condition. Three different types of composts were selected for the present study- compost made from organic components of municipal solid waste (MSWC), vermicompost (VC) made from rice straw and cow dung and compost made from phumdi, a local name given to floating mass of aquatic plants and soil found in Loktaklake in Northeastern India (PC). The plots with integrated treatments of composts and chemical fertilizer showed lower cumulative emissions of CH₄ and N₂O compared to plots treated with chemical fertilizer (CF) alone. The treatment of 50%VC + 50%CFrecorded minimumglobal warming potential (GWP) with 2112.22 kg CO₂ eq. ha^− 1and maximum of 4776.56 kg CO₂ eq. ha^− 1 from the sole application of MSWC. GWP reduced by 17.37%, 56.44%, and 16.40% in the integrated treatments of 50%MSWC + 50%CF, 50%VC + 50%CF, and 50%PC + 50%CF, respectively, compared to CF. A reduction in greenhouse gas intensity (GHGI) was also observed in VC + CF with 69.49%, followed by 48.75% in PC + CF and 22.35% in MSWC + CF compared to CF.The study showed that integrated use of chemical fertilizer with vermicompost and phumdicompost are beneficial in cultivation ofshort-duration rice crop in rain-fed conditions in Northeast India in reducing emission of CH₄ and N₂O.Itmay helplawmakersin formulatingmeasures to reduce global climate change related to agricultural activities.