Mitigation of greenhouse gas and ammonia emissions due to livestock housing management practices: Analysis of the DATAMAN database

Abstract

This study analysed management effects on methane (CH₄), nitrous oxide (N₂O) and ammonia (NH₃) emissions from pig and cattle houses, using the global DATAMAN-Housing database. Emission factor (EF) data was grouped by animal sub-category and manure type, and single-variable linear models of EF with housing practice variables (e.g. air scrubber, bedding material, with identified control values) were developed. These variables were examined for statistically significant effects on mean EFs. In closed growing pig housing systems, replacing straw with sawdust-based bedding reduced (p = 0.012) the mean EF_CH4 by 46 %. In deep pit growing pig houses, installing biological air scrubbers at the air outlet decreased the mean EF_NH3 (p = 0.031) by 24 %. Limited N₂O data showed an increased EF_N2O by 57 % (p < 0.0001), but careful interpretation is required due to the low number of observations. Frequent slurry removal from the pit below slatted floors using a scraper lowered (p = 0.011) the mean EF_NH3 by 53 %. In cubicle and loose cattle houses the mean EF_NH3 decreased when using woodchips instead of straw bedding and when changing from manure removal via scraper to flushing. The latter effects need cautious interpretation due to small sample sizes and differences in potential NH₃ emission driving factors. While these findings are promising, many practices had limited observations. Further studies are required to better quantify these practices’ mitigation potential for pig and cattle houses, ensuring co-benefits and trade-offs for all gases are captured, with data collated in the DATAMAN database for improved quantification.