为控制短期贮存畜禽粪便的温室气体排放，该文研究了塑料薄膜覆盖对肉牛粪便短期贮存过程中温室气体排放量的影响。试验采用静态箱-气相色谱法观测了秋季（日均22.87℃）肉牛粪便自然露天堆放（对照组）和塑料薄膜覆盖堆放（覆盖组）时温室气体的排放通量。结果表明：秋季覆盖塑料薄膜贮存粪便可使N2O和CO2的日均排放通量分别降低94.85%（P＜0.01）和88.85%（P＜0.01），并在试验前期（0～9 d）使CH4的日均排放通量降低了43.37%（P＜0.05），但随后的10～30 d，覆盖组粪便CH4的日均排放通量极显著高于对照组（P＜0.01）。结论：当环境温度在17.23～30.35℃时，覆盖塑料薄膜可以降低堆放贮存（0～30 d）粪便N2O和CO2的排放通量以及堆放初期（0～9 d）CH4的排放通量。因此，塑料薄膜覆盖贮存法可显著降低粪便堆放初期的温室气体排放。%In order to assess the effects of plastic sheet covering on CH4, N2O and CO2 emissions during short-term storage of beef cattle manure, the greenhouse gas emission rate was investigated in autumn (September 7, 2013 - October 6, 2013, average air temperature was 22.87℃) by the static chamber - gas chromatography (GC) method. Meanwhile, ambient air temperatures and manure temperatures (10 cm below the surface) were measured every 5 minutes using automatic temperature recorder. On the first day, manure samples were collected from the Simmental beef cattle (18-19 months old, average weight of 500 kg), mixed, homogenized and divided into 6 replicate piles (the length, width and height of every pile were 100, 100 and 20 cm, respectively). Every pile had 2 sampling sites. The following two different treatments were included in this experiment: natural storage group (control group) and plastic sheet cover storage group (covering group), and every group included 3 replicate piles and a total of 6 sampling sites. The plastic sheet was translucent polyethylene. The gas was sampled between 09:00 and 10:00 a.m. and analyzed for CH4, N2O and CO2 on the same day by using GC. The process of sampling included following steps: during each measurement, using glass syringe of 50 mL, gas samples were sampled from each treatment after 0, 10, 20 and 30 minutes when the lid was closed, passed through the connected switch valve and then were transferred into 0.1 L aluminum foil bags for storage. After each measurement, lids would be removed to make the manure be exposed to natural condition. The result showed that the density and free water content of the manure of covering group were significantly higher than that of control group (P<0.01). But the dry matter content, ash content and total nitrogen content were significantly lower than that of control group (P<0.01). In addition, plastic sheet covering storage could reduce the N2O and CO2 emissionsby 94.85% (P<0.01) and 88.85% (P<0.01), respectively. But the effects of plastic sheet covering on CH4 emissions were not consistent in different stages. The daily average CH4 emission rate of covering group was reduced by 43.37% (P<0.01) compared with that of control group in the early stage of storage (within 9 days). In the later stage of storage, the daily average CH4 emission rate of covering group was significantly higher than that of control group (P<0.01). Considering the synthesis of CH4, N2O and CO2 emission rates (CO2 equivalents), the daily average CO2 equivalent of covering group was lower than that of control group within the first 9 days (P<0.01), but the daily average CO2 equivalent of covering group was higher than that of control group at the whole storage period (P <0.05). It is concluded that covering plastic sheet should be used to reduce N2O and CO2 emissions during the first 30 days and CH4emission at the earlier stage of fresh manure storage, i.e. within the first 9 days when the air temperature is from 17.23 to 30.35℃.
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