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    The Ecological Society of America www.frontiersinecology.org

    Increasing atmospheric greenhouse-gas (GHG) concen-trations have elevated global temperature by 1C sinceindustrialization (ca 1750) and are anticipated to result inan additional 1C rise by mid-century, regardless of pro-jected rates of GHG emissions (NRC 2010; IPCC 2013).Warming will be accompanied by modified amounts andpatterns of precipitation, and a greater frequency andintensity of extreme weather events. At the ecosystemscale, the indirect effects of climate change such asincreased wildfire incidence and modified distributionsand densities of native and invasive species, includinginsects and disease-causing organisms and the direct

    effects of climate change are anticipated to be similar inmagnitude (NRC 2010). Collectively, the consequences ofclimate change, interacting with large-scale shifts inhuman land use, will likely modify ecosystem processes andthe livelihoods that they support (Polley et al. 2013).

    Rangelands comprise approximately 3040% of globalterrestrial area and deliver diverse ecosystem services; thislands predominant use, livestock grazing, contributes tothe livelihoods of millions of humans (Sayre et al. 2013).These livelihoods are vulnerable to climate change fromboth an ecological and a socioeconomic perspective(Reynolds et al. 2007). Rangelands represent ecologicallydiverse arid and semiarid systems characterized by lowplant productivity and high precipitation variability,including frequent drought. Rangeland managers oftenhave limited financial and social capital, modest infra-structure, and few options to diversify livelihoods beyondlivestock grazing, and are isolated from major urban cen-ters and governing institutions (Sayre et al. 2013). Thevulnerability of rangeland-based livelihoods to climatechange provides a strong justification for the accelerationof planning and implementation of adaptation strategies.

    Climate change is projected to have geographicallydiverse consequences on US rangelands (Polley et al. 2013).Consequently, geographically specific adaptation strategieswill be required to contend with localized challenges andopportunities. The heterogeneity among individuals andgroups both within and among geographic regions regarding the recognition, capacity, and motivation toimplement various adaptation strategies represents a secondcritical component of climate-change adaptation(Williamson et al. 2012; Joyce et al. 2013). We contend thatthe interaction between the geographic specificity of cli-mate change and the heterogeneity in the adaptive capacity

    REVIEWS REVIEWS REVIEWS

    Climate-change adaptation on rangelands:linking regional exposure with diverse adaptivecapacityDavid D Briske1*, Linda A Joyce2, H Wayne Polley3, Joel R Brown4, Klaus Wolter5, Jack A Morgan6,Bruce A McCarl7, and Derek W Bailey8

    The ecological consequences of climate change are predicted to vary greatly throughout US rangelands.Projections show warming and drying in the southern Great Plains and the Southwest, warmer and drier sum-mers with reduced winter snowpack in the Northwest, and warmer and wetter conditions in the northern GreatPlains. Primarily through their combined effects on soil water availability, these climatic changes will modifyplant production and community composition, which will, in turn, affect the livelihoods of humans who relyupon livestock grazing. The ability of rangeland managers to assess risk and prepare for climate change variesgreatly and reflects their different adaptive capacities. Geographically specific exposure to climate change and adiverse adaptive capacity to counteract these changes will require development of varied adaptation strategiesthat can accommodate the various needs and abilities of livestock managers.

    Front Ecol Environ 2015; 13(5): 249256, doi:10.1890/140266

    In a nutshell: Climate change will affect millions of people whose liveli-

    hoods are linked to livestock grazing on US rangelands Livestock grazing will be directly influenced by changes in

    the amount, nutrient content, and seasonal availability ofplant production, as well as by the adverse effects of heat,water limitation, and pathogen loads on animal performance

    Geographically specific ecological consequences and diverseadaptive capacity among managers represent underappreciatedand interacting components of climate-change adaptation

    Adaptation planning must recognize and accommodate bothgeographic specificity and varied adaptive capacity to pro-mote effective climate-change adaptation

    1Department of Ecosystem Science and Management, Texas A&MUniversity, College Station, TX *(dbriske@tamu.edu); 2HumanDimensions Research Program, US Department of AgricultureForest Service, Rocky Mountain Research Station, Fort Collins,CO; 3US Department of AgricultureAgricultural ResearchService, Grassland, Soil and Water Research Laboratory, Temple,TX; continued on p 256

  • Rangeland climate-change adaptation DD Briske et al.

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    www.frontiersinecology.org The Ecological Society of America

    of managers that is, their ability to respond to, create, andshape change in a system represents an underappreciatedbarrier to the development and implementation of adapta-tion strategies. Thus, public programs, strategies, and incen-tives to implement climate-adaptation measures will be farmore effective if they are tailored to select categories ofindividuals or social groups that are experiencing geograph-ically specific climatic consequences. The objectives of thispaper are to: (1) review the geographic specificity of climatechange in four regions of the western US, (2) identify essen-tial components of adaptive capacity that are relevant torangeland managers, (3) evaluate acknowledged adaptationstrategies and barriers to their implementation, and (4)highlight the geographic specificity of climate change andheterogeneous adaptive capacity among managers as inter-acting components of adaptation planning and implemen-tation. Although we focus on rangelands, this conceptualframework could be applicable to other natural-resourcesystems, including agriculture and forestry.

    n Subcontinental climate projections andconsequences

    The ecological consequences of climate change are antic-ipated to vary greatly among geographic regions basedupon current environmental conditions and unique

    interactions among climate-change drivers (Figure 1;Polley et al. 2013). Ecosystem processes and the servicesthat they provide will be modified by climate change andits primary drivers elevated atmospheric carbon dioxide(CO2) concentrations, warming, and modified precipita-tion regimes on soil water availability (Knapp et al.2008). Consensus projections from climate-change mod-els for the middle of the 21st century indicate that the USsouthern Great Plains, the US Southwest, and northernMexico will become warmer and drier, while the USNorthwest will become warmer and drier during summerand will experience reduced snowpack in winter; at thesame time, the US northern Great Plains and southernCanada will become warmer and wetter, especially duringthe winter (Meehl et al. 2007; IPCC 2013). These projec-tions are only approximations because reliable estimatesof future climates, especially for precipitation, are not yetpossible at regional scales (IPCC 2013). For example,results from the recent Coupled Model IntercomparisonProject Phase 5 (CMIP5) are consistent with previoustemperature projections for the southwestern US (Tayloret al. 2012; Baker and Huang 2014; J Eischeid pers comm)but forecasted less variance for annual rainfall than previ-ous simulations. Nevertheless, vulnerability assessmentsand adaptation strategies must recognize and address geo-graphically specific exposures to effectively offset cli-mate-change impacts (Joyce et al. 2013).

    Southwest

    In this region, warming and reduced precipitation will syn-ergistically decrease soil water availability, thereby dimin-ishing both the amount and nutrient content of plant pro-duction and altering plant community composition (Figure1; Polley et al. 2013). Declines in water availabilitydecrease plant growth and shorten the growing season,thus reducing available livestock forage. Collectively,changes in precipitation and temperature regimes mayalter plant species composition and plant phenology tomodify the seasonal availability of high-quality forage(Walther 2003; Craine et al. 2009). The digestibility andnutritive value of plant tissues are diminished by the highercarbon-to-nitrogen (C:N) ratio that accompanies plantgrowth under elevated atmospheric CO2 conditions, andby the accelerated leaf senescence induced by water stress(Morgan et al. 2004). Reduced nutrient intake, higher tem-peratures, and more frequent heat stress are likely tofurther reduce livestock production and adversely affectpeople whose livelihoods are dependent on it (CCSP2008; Howden et al. 2008). More frequent and severedroughts are anticipated to modify plant species composi-tion and cover directly by contributing to episodic plantdie-offs and indirectly through increasing the frequency offire events. In the Mojave Desert and Great Basin over thepast 20 years, increased fire frequency has converted somedesert shrublands and shrub steppe communities to annualgrasslands (CCSP 2008; Balch et al. 2013).

    Figure 1. Climate-change projections for US rangelands illustrat-ing the unique exposures to and potential consequences forlivestock production in four geographic regions. Projections weregenerated from recent simulations of CMIP5 (courtesy of JEischeid) and data were obtained from Taylor et al. (2012) andBaker and Huang (2014). Regional designations follow those ofUSGCRP (2009), except that the Great Plains have been dividedinto two separate regions, the northern and southern Great Plains,to