title: Carbon dioxide and methane emissions from the scale model of open dairy lots.
abstract: To investigate the impacts of major factors on carbon loss via gaseous emissions, carbon dioxide (CO2) and methane (CH4) emissions from the ground of open dairy lots were tested by a scale model experiment at various air temperatures (15, 25, and 35 °C), surface velocities (0.4, 0.7, 1.0, and 1.2 m sec(-1)), and floor types (unpaved soil floor and brick-paved floor) in controlled laboratory conditions using the wind tunnel method. Generally, CO2 and CH4 emissions were significantly enhanced with the increase of air temperature and velocity (P < 0.05). Floor type had different effects on the CO2 and CH4 emissions, which were also affected by air temperature and soil characteristics of the floor. Although different patterns were observed on CH4 emission from the soil and brick floors at different air temperature-velocity combinations, statistical analysis showed no significant difference in CH4 emissions from different floors (P > 0.05). For CO2, similar emissions were found from the soil and brick floors at 15 and 25 °C, whereas higher rates were detected from the brick floor at 35 °C (P < 0.05). Results showed that CH4 emission from the scale model was exponentially related to CO2 flux, which might be helpful in CH4 emission estimation from manure management.
  
  
  
  Gaseous emissions from the open lots are largely dependent on outdoor climate, floor systems, and management practices, which are quite different from those indoors. This study assessed the effects of floor types and air velocities on CO2 and CH4 emissions from the open dairy lots at various temperatures by a wind tunnel. It provided some valuable information for decision-making and further studies on gaseous emissions from open lots.
authors.affiliation: a Department of Agricultural Structure and Bioenvironmental Engineering , Key Laboratory of Agricultural Engineering in Structure and Environment, College of Water Resources and Civil Engineering, China Agricultural University , Beijing , People's Republic of China.
authors.forename: Luyu
authors.initials: L
authors.lastname: Ding
authors.affiliation: a Department of Agricultural Structure and Bioenvironmental Engineering , Key Laboratory of Agricultural Engineering in Structure and Environment, College of Water Resources and Civil Engineering, China Agricultural University , Beijing , People's Republic of China.
authors.forename: Wei
authors.initials: W
authors.lastname: Cao
authors.affiliation: a Department of Agricultural Structure and Bioenvironmental Engineering , Key Laboratory of Agricultural Engineering in Structure and Environment, College of Water Resources and Civil Engineering, China Agricultural University , Beijing , People's Republic of China.|b Beijing Engineering Research Center on Animal Healthy Environment , Beijing 100083 , People's Republic of China.
authors.forename: Zhengxiang
authors.initials: Z
authors.lastname: Shi
authors.affiliation: a Department of Agricultural Structure and Bioenvironmental Engineering , Key Laboratory of Agricultural Engineering in Structure and Environment, College of Water Resources and Civil Engineering, China Agricultural University , Beijing , People's Republic of China.|b Beijing Engineering Research Center on Animal Healthy Environment , Beijing 100083 , People's Republic of China.
authors.forename: Baoming
authors.initials: B
authors.lastname: Li
authors.affiliation: a Department of Agricultural Structure and Bioenvironmental Engineering , Key Laboratory of Agricultural Engineering in Structure and Environment, College of Water Resources and Civil Engineering, China Agricultural University , Beijing , People's Republic of China.|b Beijing Engineering Research Center on Animal Healthy Environment , Beijing 100083 , People's Republic of China.
authors.forename: Chaoyuan
authors.initials: C
authors.lastname: Wang
authors.affiliation: c Department of Engineering , Aarhus University , Tjele , Denmark.
authors.forename: Guoqiang
authors.initials: G
authors.lastname: Zhang
authors.affiliation: c Department of Engineering , Aarhus University , Tjele , Denmark.
authors.forename: Simon
authors.initials: S
authors.lastname: Kristensen
mesh_terms: D000393:Air Pollutants / Q000032:analysis*; D002245:Carbon Dioxide / Q000032:analysis*; D003612:Dairying; D008372:Manure; D008697:Methane / Q000032:analysis*; D008962:Models, Theoretical; D012987:Soil / Q000737:chemistry; D013696:Temperature
chemical_list: D000393:Air Pollutants; D008372:Manure; D012987:Soil; D002245:Carbon Dioxide; D008697:Methane