Emissions Of Greenhouse Gases From Dairy Manure And Influencing Factors

Animal manure is a important source of greenhouse gases(GHG),which emits lots of GHG when decomposing. In order to find out the GHG emission from manure in different conditions and influencing factors, the static chamber-GC sampling system with manual is established to measure GHG emission from manure with cover, different piled patterns and different temperatures. The influencing factors are also studied. The following items are the main conclusion of this paper:1. The covers will influence the GHG emission from manure, but the influence is different in different studies. The emission of CO₂ and N₂O decrease from manure covered by cornstalk, but the influence to the emission of CH₄ is different in different period. The emission of CO₂ in the third period and the emission of CH₄ and N₂O in the fourth period is significantly different, The emission of GHG in the other periods is not significantly different.2. The GHG emission from manure is influenced by the pattern of pile, and the emission in different treatments are significantly different except the CH₄ emission from the treatment of 50cm and 25cm height in summer experiment. As a whole, CO₂ and N₂O emission from the treatment of adding 10kg manure per day is high, and low at the treatment of 50cm height, but the N₂O emission shows a reverse trend.3. Temperature is the main factor influencing the GHG emission from manure, and the emissions from manure have a good relativity with the temperature of manure. The temperature is lower, the GHG emission is smaller. The emission increases with the increasing of the manure temperature..CO₂ emission from manure in different temperatures is significantly different, and the CH₄ emission is also significantly different except the treatment of 5℃and 15℃. When the temperature is 35℃, N₂O emission is significantly different with other treatments, and the emission is not significantly different between other treatments.4. The GHG emission in different treatments is significantly different. (1) Covering treatment: in the early time of the experiment, CO₂ emission rate is high, then decreases gradually later in the first and fourth periods, but is always steady in the second and third periods. CH₄ emission rate is always steady in the first, second and third periods, but the rate increases gradually in the later time of the experiment in the fourth period .Meantime the N₂O emission rate is also steady in the first and second periods, but the rate increases gradually in the later time of the experiment in the third and fourth periods. (2)Treatment of piled pattern: CO₂ and CH₄ emission rates are high in the early time of the experiment and decrease gradually later. N₂O emission rate is very low at the beginning and increases gradually later. (3)Treatment of different temperatures: when the temperature is 5℃,GHG emission decreases gradually, and at 15℃,the emission decreases first, then increases. When the temperature increases to 25℃or 35℃, CO₂ emission rate is high in the mid of the experiment, and steady at the other time. CH₄ and N₂O emission rates increase gradually on the whole.