What place for livestock on a re-greening earth?
This paper contemplates the role of livestock and livestock management in providing helpful ecosystem services, “re-greening the earth,” through a literature review considering both the well documented injurious and highly beneficial outcomes of ruminants on landscapes.
Review of Evidence on Drylands Pastoral Systems and Climate Change: Implications and Opportunities for Mitigation and Adaptation
This report highlights the importance of drylands, grazing lands and livestock-based livelihoods and illustrates their relationship with climate and with climate mitigation through the adoption of methodologies to restore soil. The editors write “There is a great potential for carbon sequestration in drylands because of their large extent and because substantial historic carbon losses mean that drylands soils are now far from saturation (FAO/LEAD, 2006). Lal (2004) estimates that soil carbon sequestration in the dryland ecosystems could achieve about 1 billion tonnes C per year but reaching this will require a vigorous and coordinated effort at a global scale.” It should be noted that more recent studies suggest that the drawdown potential might be higher.
Challenges and opportunities for carbon sequestration in grassland systems: a technical report on grassland management and climate mitigation
This 2010 FAO report makes a strong case for grasslands restoration as a climate mitigation strategy and “improved grazing management” as one of the most important practices for enhancing soil carbon stocks.
Soil Carbon Sequestration in Grazing Lands: Societal Benefits and Policy Implications
This paper from 2010 is a compilation of previous studies on grazing lands and carbon drawdown which themselves date from the 1990s. It shows that grazing lands/rangelands are major stores of terrestrial carbon, occupying approximately 3.6 billion hectares and accounting for about one-fourth of potential carbon (C) sequestration in world soils. Drawdown rates via grazing and on restored semi-arid savanna are reported to be as high as 2.75 tons per hectare per year.
Global Warming and Pasture-Raised Beef Production in the United States
This report evaluates the prospects for changing management practices to reduce the climate impact of the time beef cattle spend on pasture or rangeland. Improved practices are most readily applied to the finishing stage of fully pasture-raised systems—a growing alternative to CAFOs, given research showing that pasture finishing has nutritional and environmental benefits. In the long term, the use of climate-friendly best practices in the United States may lead to substantial cuts in global warming emissions if adopted in countries where beef production accounts for a greater share of those emissions.
GHG Mitigation Potential of Different Grazing Strategies in the United States Southern Great Plains
This paper demonstrates that enteric emissions (methane) from cows are not a climate impediment when the animals are managed in a way that builds soil, thus, capturing carbon. Specifically, using a life cycle assessment that weighs emissions against sequestration, it calculates a net drawdown of approximately 2 tons of carbon per hectare per year (0.8 tons per acre per year) after a conversion from heavy continuous to multi-paddock grazing.
Emerging land use practices rapidly increase soil organic matter
This paper studies three farms converted from cropland to management intensive grazing. “Farms accumulated C at 8.0 Mg ha−1 yr−1, increasing cation exchange and water holding capacity by 95% and 34%, respectively.”
Potential mitigation of midwest grass-finished beef production emissions with soil carbon sequestration in the United States of America
This partial life cycle assessment (LCA) compared two grazing management strategies: 1) a non-irrigated, lightly-stocked, high-density system (MOB) and 2) an irrigated, heavily-stocked, low-density system (IRG). Results indicated that when soil carbon sequestration (SCS) potential was included, each grazing strategy could be an overall sink, with the MOB system found to have greater SCS than the IRG system.
Grazing management impacts on vegetation, soil biota and soil chemical, physical and hydrological properties in tall grass prairie
This paper finds that adaptive management using multi-paddock grazing produced superior outcomes on vegetative cover and soil. In a comparison of four grazing schemes: light continuous (LC), heavy continuous (HC), multi-paddock with adaptive management (MP), ungrazed areas – exclusion (EX), the MP lots were better in almost every measure. Factors measured included soil organic matter (SOM), water infiltration rate, water volumetric percentage, cation exchange capacity, fungal/bacterial ratio, percent bare ground and standing biomass of desirable and undesirable plants.
Impacts of soil carbon sequestration on life cycle greenhouse gas emissions in Midwestern USA beef finishing systems
This paper does a greenhouse gas life cycle analysis (LCA) comparison of two grazing finishing systems in the Upper Midwest, USA: feedlot finishing and Holistic Planned Grazing, which the authors refer to as adaptive multipaddock (AMP). It finds that AMP finishing improved soil organic carbon by 3.5 tons per hectare per year. This resulted in a net negative footprint of 6.6 kg of carbon dioxide equivalence per kg of carcass-weight.
