摘要
为了研究锯末和稻草2种材料覆盖以及不同厚度的锯末覆盖对牛粪堆存过程中氨气(NH3)和温室气体(N2O、CH4和CO2)排放量的影响,采用静态箱的方法测试了不同覆盖厚度(1、3和5 cm)和2种材料(锯末和稻草)覆盖下牛粪NH3、N2O、CH4和CO2排放量。结果表明,在不同厚度锯末覆盖的试验中,与不覆盖处理组相比,覆盖降低了牛粪NH3和CO2累积排放量,但覆盖显著增加了牛粪N2O和CH4累积排放量(P<0.05);3个覆盖处理组内,NH3、N2O和CO2排放量随着覆盖厚度的增加而下降,然而,CH4排放量随着覆盖厚度的增加而升高;1、3和5 cm厚锯末覆盖的牛粪总温室气体排放量分别为108.61、103.57和101.36 g/kg,与1 cm锯末覆盖相比,3和5 cm厚锯末覆盖的牛粪总温室气体排放量显著降低(P<0.05)。在相同质量的锯末(2 cm厚)和稻草(6 cm厚)2种材料覆盖的比较试验中,2种材料覆盖都显著降低了牛粪NH3和CO2的累积排放量(P<0.05),但同时也显著增加了CH4的累积排放量(P<0.05);锯末覆盖增加了牛粪N2O累积排放量(P<0.05),而稻草覆盖则降低了牛粪N2O累积排放量(P<0.05)。与锯末覆盖相比,稻草覆盖显著增加了CH4的累积排放量(P<0.05),但同时显著降低了牛粪CO2的累积排放量(P<0.05);锯末覆盖和稻草覆盖牛粪总温室气体排放量分别为101.51和109.46 g/kg,与锯末覆盖相比,稻草覆盖显著增加了牛粪总的温室气体排放量。试验结果表明,较厚的锯末(3和5 cm)覆盖对牛粪NH3和温室气体的减排效果更好。
Livestock production is the important source of gaseous emissions（NH3 and greenhouse gases） from agriculture. Storage of animal manure is reported to be an important agricultural source of the environmentally harmful gases. Generally, ammonia and greenhouse gas emissions from stored animal manure can be affected by environmental factors（temperature and wind speed） and storage stacking configuration. Most studies have focused on the emission of ammonia and greenhouse gases from slurry during storage. However, information of gaseous emissions from solid manure stored is limited. Material coveringis expected to be an effective method to reduce gaseous emissions from the stored manure. Thus, two experiments were set up to study gaseous emissions during storage of the solid cattle manure, and the effect of covering depth（1, 3 and 5 cm） and two different covering materials（sawdust and straw） on emissions of ammonia and greenhouse gases. Polyvinylchloride cylindrical（30 cm in diameter and 90 cm in height） static vessels were designed and built to measure ammonia and greenhouse gas emissions in the laboratory experiment. Fresh cattle manure was collected from practicing farm of Rongchang Campus of Southwest University in Chongqing. After fully mixed, manure was filled into 12 barrels（24.2 cm in diameter and 15 cm in height）. Barrels were enveloped by static vessels while measuring gaseous emissions. The stacking process commenced on May 29, 2014, and was measured for 49 days. In Experiment 1, the emissions of NH3, CH4, N2 O and CO2 from an uncovered and three sawdust-covering heaps of solid cattle manure were compared. Considering that the stacking of solid manure was only 10 cm height（about 4 kg）, sawdust covering depths of 1, 3 and 5 cm were selected. In Experiment 2, the emissions of NH3, CH4, N2 O and CO2 were quantified using solid cattle manure（about 10 kg, 25 cm stacking height） covered with sawdust（2 cm depth, 250 g） and straw（6 cm depth, 250 g） by using the method of static chamber. In Experiment 1, sawdust covering decreased cumulative NH3 emissions by 15.28%-58.13% and cumulative CO2 emissions by 4.61%-13.14% from cattle manure compared with that uncovered（P〈0.05）. However, sawdust covering simultaneously increased cumulative N2 O emissions by 6.57%-20.02% and cumulative CH4 emissions by 29.82%-36.84%（P〈0.05）. The emission of NH3, N2 O and CO2 decreased and the emission of CH4 increased with the increasing of sawdust covering depth in three treatments of sawdust covering. Considering that the indirect global warming potential of NH3-N per kilogram was calculated on the basis of an emission of 0.01 kg N2O-N and global warming potential in 100-year scale for CH4 and N2 O, cumulative greenhouse gas emissions（based on CO2） were 103.80, 108.61, 103.57 and 101.36 g/kg of manure weight for uncovered treatment, sawdust covering treatments with the covering depths of 1, 3, and 5 cm, respectively. Total greenhouse gas emissions showed a downward trend with the increasing of covering depth for covering treatments. In Experiment 2, both sawdust covering and straw covering reduced cumulative NH3 and CO2 emissions from solid cattle manure compared with that without covering during storage（P〈0.05）, but increased cumulative CH4 emission（P〈0.05）. Compared with uncovered treatment, sawdust covering increased cumulative N2 O emission from solid cattle manure（P〈0.05）. However, straw covering decreased cumulative N2 O emission（P〈0.05）. Compared with straw covering, sawdust covering decreased cumulative NH3 emission by 16.14% from solid cattle manure. Cumulative N2 O emission from solid cattle manure increased significantly by using sawdust covering compared with straw covering（P〈0.05）, 33.39 mg/kg for sawdust covering and 22.30 mg/kg for straw covering, respectively. Cumulative CH4 emissions from solid cattle manure covered with straw was significantly higher than that from solid cattle manure covered with sawdust（P〈0.05）, 2.53 vs. 2.07 g/kg, respectively. However, cumulative CO2 emissions from solid cattle manure covered with straw was significantly lower than that from solid cattle manure covered with sawdust（P〈0.05）, 32.62 vs. 34.65 g/kg, respectively. Cumulative greenhouse gas emissions were 94.14, 101.51 and 109.46 g/kg of manure weight based on CO2 for uncovered, sawdust covering and straw covering, respectively. Compared with sawdust covering, straw covering increased significantly total greenhouse gas emissions from solid cattle manure. The results show that the treatments with thicker sawdust-covering（3 and 5 cm） have better effect of reduction emission for greenhouse gases.
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2015年第6期223-229,共7页
Transactions of the Chinese Society of Agricultural Engineering
基金
中央高校基本科研业务费专项(XDJK2011C028)
西南大学博士基金(08BSr05)
关键词
粪便
氨气
温室气体
锯末
稻草
覆盖厚度
manure
ammonia
greenhouse gases
sawdust
straw
covering depth
