Field Measurement of Carbon Dioxide, Methane and Nitrous oxide Emissions from Manure Stockpile and Open Exercise Yard of a Typical Dairy Farm in China by Chamber Technique

Abstract. In typical dairy production and management system of China, outdoor exercise yard and stockpiles play a major role in emissions of pollutants to atmosphere. GHG (CO 2 , CH 4  and N 2 O) emissions from brick-paved yard and manure stockpiles of a typical dairy farm in Beijing were measured by closed chamber in four different seasons. There are cubicles in the yard and manure in the yard was removed once a day by tractor. CO 2 , CH 4  and N 2 O emissions from the yard were within the range of 0.2~42 mg m -2  min -1 , 1~616 ug m -2  min -1  and 0.3~129 ug m -2  min -1  in different seasons, respectively. GHG emissions from exercise yard showed a seasonal variation. GHG emission rates from different zones (cubicle zone vs. aisle zone) of the lot greatly varied, and the emissions were significantly affected by manure removal strategy (P 2 and CH 4  emissions (P 2 O emissions showed a disparity in different seasons. Compared with the result before manure removal, N 2 O emissions were greatly higher after manure removal both at aisle and cubicle zones (P 2 , CH 4  and N 2 O emissions from manure stockpiles were 4~168 mg m -2  min -1 , 0.02~1.79 mg m -2  min -1  and 0.62~536 ug m -2  min -1 , respectively. GHG emissions from stockpile also showed a seasonal variation. Volatile solid in manure and temperature were the key factors affecting CO 2  and CH 4  emissions. N 2 O emissions were affected by manure storage duration.