ABSTRACT
The need for improved livestock waste management in developing countries has been emphasized by various researchers. Consideration has been given globally to advocacy for a transition from fossil energy system to Renewable Energy (RE), based on several socio-economic and environmental advantages. Green House Gas (GHG) from agricultural sector of Anambra State, with appropriate waste management strategy such as Anaerobic Digestion (AD) will definitely mitigate Methane emission hazards and will as well supply the much needed energy for domestic and industrial uses. An investigation was carried out in this study to estimate the Methane Emission Potential (MEP) of the study area as a result of poor livestock waste management system practiced in the area. This was achieved by incorporating Geographical Information System (GIS) capability to the Methane estimation. The result of the study shows that two Local Government Areas (LGA) which are Anambra West and Anambra East were the least in MEP with virtually none and 0.000646 Gg/year respectively. Idemili North LGA with MEP of 0.017962 Gg/year was observed to be the highest in Methane emission. On incorporating spatial density mapping on MEP, Onitsha North and Idemili North LGA were identified as the highest risk LGAs, with MEP of 0.00018 Gg/year and 0.000272 Gg/year respectively. The study suggests that an improved livestock waste management system using AD should be incorporated in the study area especially in the high risk zones of Onitsha and Idemili North LGA.
ABSTRACT
Methane emission from two rice fields of Lambhvel village, Anand district, central Gujarat, India, was measured for whole cultivation period during pre-summer season. Along with the methane emission, soil chemistry of the two rice fields (Organic carbon, PO4 -2 and SO4 -2) was determined. The methane emission ranged from 105.67 to 720.64 mg m-2hr-1, having maximum emission during noon period (11 am to 1 pm) of the day at the rice field 1. Besides, at rice field 2, the methane emission ranged between 201.59 to 430.94 mg m-2hr-1, having maximum peak during same period (11 am to 1 pm) of the day. The results of the current investigation confirm that the methane emission vary substantially between two rice fields, and suggest that soil chemistry and flood water depth might control the methane emission in both the rice fields and suppressed by the phosphate and sulphate concentrations. The greater methane emission was gradually declined from first trip to fourth trip. Correlation analysis, ANOVA and F-test showed that the methane emission from both the sites has positive correlation with organic carbon and negative correlation with sulfate and phosphate content of the soil and the details of these reasons are discussed in this paper.