Livestock as Sources of Greenhouse Gases and Its Significance to Climate Change

Abstract

This chapter outlines the role of livestock in the production of greenhouse gases (GHGs) that contributes to climate change. Livestock contribute both di‐ rectly and indirectly to climate change through the emissions of GHGs such as carbon dioxide (CO 2), methane (CH 4), and nitrous oxide (N 2 O). As animal production systems are vulnerable to climate change and are large contribu‐ tors to potential global warming, it is vital to understand in detail enteric CH 4 emission and manure management in different livestock species. Methane emissions from livestock are estimated to be approximately 2.2 billion tonnes of CO 2 equivalents, accounting for about 80% of agricultural CH 4 and 35% of the total anthropogenic CH 4 emissions. Furthermore, the global livestock sec‐ tor contributes about 75% of the agricultural N 2 O emissions. Other sources of GHG emission from livestock and related activities are fossil fuels used for as‐ sociated farm activities, N 2 O emissions from fertilizer use, CH 4 release from the breakdown of fertilizers and from animal manure, and land-use changes for feed production. There are several techniques available to quantify CH 4 emission, and simulation models offer a scope to predict accurately the GHG emission from a livestock enterprise as a whole. Quantifying GHG emission from livestock may pave the way for understanding the role of livestock to climate change and this will help in designing appropriate mitigation strat‐ egies to reduce livestock-related GHGs.