Ammonia and greenhouse gas emissions from a dairy cattle barn with a daily manure collection system.

摘要

This study quantifies concentrations and emission rates (ER) of ammonia (NH₃) and greenhouse gases (GHG), including carbon dioxide (CO₂) and methane (CH₄), during four seasons of one year in north China from a naturally ventilated dairy cattle barn with a daily manure collection system, with each monitoring episode lasting five consecutive days. Gaseous concentrations of background and exhaust air were measured using an infrared photoacoustic multi-gas monitor with a multi-channel sampler. About 120 gas concentration measurements were taken for each season. Barn ventilation rate (VR) was determined by CO₂ mass balance using literature metabolic rate data for dairy cattle. Both gas concentrations and ER showed considerable diurnal and seasonal variations. Annual mean (+or-SD) ER of NH₃, CO₂, and CH₄ for the monitored dairy cattle barn were 75.5+or-25.3 g d-1 cow-1, 8.9+or-0.7 kg d-1 cow-1, and 305+or-119 g d-1 cow-1, respectively. Ammonia and greenhouse gas ER from the current study were within the ranges of values reported for dairy cattle.