Effects of land-use conversion from double rice cropping to vegetables on CO2 and CH4 fluxes in southern China. Effects of applying controlled release fertilizers on N2O emission from a lateritic red soil. N2O emission from grassland soils and the teedback effect or nutrient changes resulting from global warming Combined effects of nitrogen fertilization and biochar incorporation on methane and nitrous oxide emissions from paddy fields in rice-wheat annual rotation system