GREENHOUSE GAS EMISSIONS FROM BIO-BEDDING IN COW FARMING
DOI:
https://doi.org/10.71254/k4p8jj93Keywords:
Greenhouse gases (GHGs), bio-bedding, emissions, cow farming, agricultural by-productsAbstract
Researching a way to reduce greenhouse gas (GHG) emissions from livestock waste is very important now. The study assessed of the GHG emissions from biological bedding made from straw and acacia bark in beef cattle raising. The experiment was conducted with 20 cows on a barn with 100 m2 area. The experiment time was 54 days and there were 6 sampling times. The results showed that the GHG emissions in the early stages of using bedding was mainly the aerobic decomposition process, the amount of CO2 emissions was quite large and reached a maximum in the period from 21 days to 32 days, then it decreased and the process Anaerobic became dominant. During the first 42 days, the CH4 emissions was very low, from only 0.6 grams/ton of dry bedding/day to 151 grams/ton of dry bedding/day; then increased very strongly at the 54 - day sampling up to 2.28 kg/ton of dry bedding/day and is predicted to continue to increase. IBM SPSS statistical software (2023) shows that the CH4 emission was proportional to the microbial-density and temperature while it was inversely proportional to the porosity. The N2O emissions peaked at the 32th day and then decreased sharply. CH4 emissions increased very rapidly after 42 days of using the bedding while both CO2 and N2O emissions decreased. Comparing the average converted emission factor over 42 days (F42) and 54 days (F42) showed that F42 was much smaller than F54. Thus, bio-bedding should be replaced or partially replaced after 42 used days to limit methane emissions. In addition, the H2S, NH3 and SO2 indicators of air samples around the cages in some sampling times exceeded the allowable thresholds of surrounding air environment (QCVN 05:2023/BTNMT) of the Ministry of Natural Resources and Environment but all of them were very low compared to the barn hygiene standards (QCVN 01-79:2011/BNNPTNT) of the Ministry of Agriculture and Rural Development.