Study On Methane Flux Emitted From Manure Pond On Medium Scale Pig Farm

The methane (CH4) that emissions from animal manure of livestock farm were one of the main sources to globe GHGs emissions, In order to investigate CH₄ emissions rule from manure pond on medium scale pig farm for China special management method and climate situation, and to estimate the emission potential of pond in pig farm, to offer some basal date to global GHGs control, the CH₄ fluxes were measured in one pond of Baichuanquan livestock farm of Changping district of north Beijing, the measure continued almost 10 mouths that from Apr.2006 to Feb.2007,and the static enclosed chamber /GC technique was used during the period. By collecting and analyzing the date , the variations of CH4 fluxes from manure pond were obtained, at the same time, the possible environmental factor that can effect the CH4 fluxes from manure pond were measured, and the impact were analyzed.The main conclusions are as follows:1. The obvious seasonal patterns of CH4 fluxes from manure pond on medium scale pig farm are observed in the long-term measurements. The rank of average emission rate of CH4 fluxes in different seasons is: flux in summer /autumn >flux in spring>flux in winter, the Max CH4 fluxes can reach 800mg·m^-2·h^-1 in summer and the average CH4 fluxes in spring is about100mg·m^-3·h^-1 , the lowest CH4 fluxes is zero that occurs in winter.2. At the same time, the CH₄ fluxes from manure pond has obvious daily change rule. Date show that the maximal emission flux occurred at 2:00p.m., and the minimal flux occurred after 0:00a.m., and the change rule of the CH4 fluxes from manure pond has relativity with the change rule of the all-day temperature. But the special situation also occurred in sometime, the change of flux always lags behind the change of temperature.3. The most possible factor that can affect the CH₄ fluxes from manure pond is: temperature, wind speed, pH of pond, VS of manure, TOC of waste water on pond. But not all environmental factors can observably affect the CH₄ fluxes, the research indicates that: temperature, wind speed is two important factors among those environmental factors, the other environmental factors is not study in the research. But the effect between temperature and wind speed is not in the same level, the influence of temperature always beyond the influence of wind speed in the CH₄ fluxes from manure pond on mostly time, The wind speed operate just in some cold season, as winter.4. The average CH₄ fluxes in the pond is 42kg /ha ? d, have the some difference with other countries, the main reason is possible VS difference of feed, so some examition should be done in the future in order to find the really reason.