Management Practices for Minimizing the Environmental Footprint of Beef Cattle Grazing Systems Charles W. Rice University Distinguished Professor Department of Agronomy

Establish baselines for C & N fluxes, energy and H 2 O use and storage.

Measuring Enteric Methane Losses Incoming air Outgoing air AC Feces collection Urine collection Duplexer Gas analyzers Air Flow System

Multi-scale and multi-disciplinary data assimilation

Conduct comprehensive life cycle analyses (LCAs) of mixed cow-calf and stocker cattle producers’ farms.

Issues Scaling up Landscape variability Climate variability

Grazing Land Management Mitigation Potential Ease Available Grazing Lands – Plant management C: Grass varieties /composition, increased productivity, nutrient management. Stocking densities, carrying capacity, fodder banks, improved grazing management N 2 O: nitrification inhibitors Grazing Lands – Animal management C: Stocking densities, carrying capacity management, fodder banks, improved grazing management CH 4 N 2 O: Stocking density, waste management Grazing Land- Fire management C: Improved use of fire, fire prevention, improved prescribed burning Revegetation C: Establishment of vegetation CH 4 : Increased grazing by ruminants may increase emissions N 2 O: Reduced N inputs will reduce emissions

Livestock – feeding CH 4 : Improved feed and dietary additives to reduce emissions from enteric fermentation; including improved forage, dietary additives, ionophores / antibiotics, propionate enhancers, archaea inhibitors, nitrate and sulphate supplements Livestock – breeding and other long term management CH 4 : Improved breeds with higher productivity or with reduced emissions; microbial technology such as archaeal vaccines, methanotrophs, acetogens, defaunation of the rumen, bacteriophages, probiotics; improved fertility Manure management CH 4 : Manipulate bedding and storage, anaerobic digesters; biofilters, dietary additives N 2 O: Manipulate diets to reduce N excreta, nitrification inhibitors, urease inhibitors, manure application practices, grazing management

Mitigation potential for the AFOLU sector by 2030

Soil Microbial Activity Soil Organic Matter (C) CO 2 Management Harvestable Yield Climate Soils Sunlight

Soil Organic Carbon Microbial Activity/ Composition Nutrient Cycling Soil Structure Soil Biodiversity Water Erosion & Availability Gaseous Emissions Plant Growth Yield Environmental Services Sustainability

Grazinglands C sequestration Shortgrass prairie Mg C ha -1 yr -1 Derner et al. 1997; Reeder and Schuman 2002 Northern mixed-grass prairie 0.30 Mg C ha -1 yr -1 Schuman et al. 1999; Frank 2004 Southern mixed-grass prairie Australian perenial No change ∼ 0.35 t C ha −1 yr −1 Fuhlendorf et al Young et al Derner and Schuman, 2007

34.6Unburned 41.2*Burned 34.5 Mowed 41.5*Control 40.7*N fertilized 36.0Control Soil C (Mg ha -1 ) Management of Tallgrass Prairie

GHG emissions

Enteric Methane Mitigation Timeline Dietary Supplements Breeding Vaccination BMPs “Silver bullet” Rumen manipulation ImmediateLonger Term Eckard, Grainger & de Klein 2010 Herd Management Biological control Likely Impact Timeline HighLowConfidence

Mitigation activities in the Agriculture sector Reductions in CH 4 or N 2 O emissions from croplands, grazing lands, and livestock. Conservation of existing soil carbon stocks. Reductions of carbon losses through management changes or by reducing losses of carbon-rich ecosystems. Enhancement of carbon sequestration in soils, biota, and long-lived products. Changes in albedo resulting from land-use and land-cover change that increase reflection of visible light.

Summary Agriculture unique among the sectors since the mitigation potential is derived from both an enhancement of removals of greenhouse gases (GHG), as well as reduction of emissions through management of land and livestock. There are barriers to implementation, including accessibility to financing, poverty, institutional, ecological, technological, diffusion and transfer barriers. Polices governing practices need to account for both mitigation and adaptation. Need appropriate metrics and baselines

Thank you! Chuck Rice

Strategy/ Animal System † Goal ‡ Potential OutcomeStudy Sites Patch Burning/ CC, S † AIncrease animal use efficiency, decrease nutrient loss, improved nutrient usage NF, OSU, KSU Animal Efficiency/ CC, S M, ASelecting of animals that use forage more efficiently may decrease GHG emissions as well as increase productivity NF, ARS-ER, producers Feed Supplements/ CC, S MSupplementation (especially starch and fat) has been found to decrease enteric CH 4 emissions ARS-ER, SRNF ARS-B Shift in Pasture Type/ CC, S MIncreasing forage quality should decrease GHG emissions ARS-ER, SRNF, producers Early Weaning/ CCMIncrease production per GHG unitNF, ARS-ER Incorporate Legumes / CC, S ADecrease N applicationNF Grazing Systems/ CC, S MUtilize appropriate grazing systems to maintain high quality forages NF, ARS-ER, OSU, producers Ionophores/ CC, SMIncreased rumen efficiency,improved digestibilityNF, ARS-ER Match Grazing System to Site/ S M,ASelection of correct ecological sites to meet the needs of stocker program ARS-ER Adaptation and mitigation strategies to be evaluated. 22 † CC=cow-calf, S=stocker; ‡ A=Adaptation, M=Mitigation