Climate Change in Grassland Ecosystems

Grasslands are a widespread and globally important biome providing key ecosystem services, including carbon storage, regulation of the water cycle and diverse assemblages of plant and animal species. Grasslands also provide many important benefits to humans, such as food and forage for livestock. Climate changes manifest as temperature fluctuations, increased intensity of drought and flood cycles and increased atmospheric CO2 concentrations. These changes are impacting species growth responses, plant composition and other key grassland processes. In addition to the direct consequences of climate change, secondary (or indirect) impacts of climate change threaten grassland ecosystems. These include changes in land-use and land-cover, agricultural conversion, woody encroachment, invasive species and atmospheric nitrogen deposition. In this chapter, we discuss the direct and indirect impacts of climate change on grasslands generally, while using case studies from specific global grassland types to illustrate key threats and climate change impacts. We specifically provide examples of how direct and indirect climate changes interact, increasing the vulnerability of grasslands. In the final section of this chapter, we outline a climate action plan for grassland ecosystems that includes efforts focused at multiple scales, including the individual, community and global levels. These climate actions can be used to influence policy, reduce the rate of climate change, conserve and restore grasslands and, most importantly, need to begin immediately. Collectively, we explain the general ecological processes in grasslands, illustrate the consequences of climate change on this ecosystem and identify potential solutions to maintain the viability and persistence of grassland ecosystems for the foreseeable future.