Submitted to: Proceedings ASAE Conference Clean Water Clean Environment
Publication Type: Proceedings
Publication Acceptance Date: October 11, 2000
Publication Date: N/A
Earthen manure storage units serve as sources of volatile organic compounds, ammonia, methane, and nitrous oxide gases to the atmosphere. The generation of these gases and the exchange between the manure surface and the atmosphere is controlled by the microclimate surrounding the manure storage unit. There have been no direct measurements of the microclimate around and within earthen manure storage units so we developed a study to quantify these changes for units located in Iowa and Oklahoma. These measurements were made from the spring of 1996 through 1998 using automated data acquisition systems equipped with air temperature, water vapor, and windspeed sensors. One system was placed in the center of the manure unit to measure the conditions directly over the liquid surface and the temperature profile of the liquid. Temperature profiles within the liquid revealed that the upper 25 cm were often iosthermal throughout the year due to large amount of biological activity. Air temperatures around the manure storage units were affected by the wind direction and evaporative conditions on a given day. Water vapor concentrations were a function of windspeed and the surrounding vegetative surface. Transport of gases away from production units was predicted using an atmospheric transport model that allowed the terrain and placement of buildings as input into the model.