Mitigation of Greenhouse Gas Emissions by Water Management in a Forage Rice Paddy Field Supplemented with Dry-Thermophilic Anaerobic Digestion Residue

• Published in: Water, air, and soil pollution Vol. 225; no. 9; pp. 1 - 13
• Main Authors: Riya, S, Katayama, M, Takahashi, E, Zhou, S, Terada, A, Hosomi, M
• Format: Journal Article
• Language: English
• Published: Cham Springer-Verlag 01.09.2014; Springer International Publishing; Springer; Springer Nature B.V
• Subjects: Agricultural chemicals; Agriculture; Agrochemicals; Air pollution; Anaerobic digestion; Analysis; Atmospheric Protection/Air Quality Control/Air Pollution; Biogas; Biomass energy; Carbon; Cattle; Climate Change/Climate Change Impacts; Copy number; detection limit; Detection limits; Drainage; Earth and Environmental Science; Emissions; energy; Energy sources; Environment; Environmental monitoring; Environmental protection; Fertilizers; Flooding; Floods; Fluxes; Forage; Forages; genes; Glass transition temperature; Greenhouse effect; greenhouse gas emissions; Greenhouse gases; Hogs; Hydrogeology; Irrigation; Loam soils; Manures; Methane; methanogens; Mitigation; Nitrogen; Nitrous oxide; Nitrous oxides; Oryza sativa; paddies; Pig manure; range management; Residues; Rice; Rice fields; Rice hulls as fuel; Rice straw; soil; Soil Science & Conservation; Studies; summer; surge irrigation; Water management; Water Quality/Water Pollution; Watershed management; Methane; Methanogenic archaea; Forage rice; Water management; Dry-thermophilic anaerobic digestion; Biogas residue
• ISSN: 0049-6979; 1573-2932
• DOI: 10.1007/s11270-014-2118-3

Dry-thermophilic anaerobic co-digestion (DTAD) can be used to treat forage rice straw and pig manure and generate biogas as an energy source. Solid residue produced from DTAD process can be used as a fertilizer in forage rice fields, while addition of the residue could increase methane (CH₄) and nitrous oxide (N₂O) emissions from the soil. We evaluated the effects of adding DTAD residue and water management on CH₄ and N₂O emissions from a forage rice field. Three treatments were evaluated: (a) 100 kg N · ha⁻¹ chemical fertilizer and continuous flooding (CC); (b) residue addition (300 kg N · ha⁻¹ DTAD residue) with continuous flooding (RC); and (c) residue addition with intermittent irrigation (RI). RC and RI showed higher CH₄ fluxes than CC throughout the growing period. After a midsummer drainage, RI showed higher soil Eh values and lower CH₄ fluxes (mean, 7.6 mg C · m⁻² · h⁻¹) than those in RC (mean, 18.6 mg C · m⁻² · h⁻¹). Abundance of mcrA gene copy number was not different between RC and RI, suggesting CH₄ flux was reduced by suppression of methanogenic activity by intermittent irrigation. Cumulative CH₄ emissions during the cultivation period were 105, 509, and 306 kg C · ha⁻¹ in CC, RC, and RI, respectively. N₂O fluxes were within detection limits in all treatments. Our results, to our knowledge, are the first to show greenhouse gas emission from forage rice fields supplemented with DTAD residue and of the effectiveness of water management in CH₄ mitigation.