Rangelands and a changing climate

Authors: Moffet, Corey

Submitted to: ASA-CSSA-SSSA Annual Meeting Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: 8/24/2018
Publication Date: N/A
Citation: N/A

Interpretive Summary:

Technical Abstract: Rangelands occupy approximately 300 million ha of US land area (31%). The majority of this land type is found in the 17 western most states and rangeland is an important resource for livestock production in the region. These lands are important to society for several other ecosystem services such as providing clean water, wildlife habitat, and recreation. In this presentation, I focus on their use as a source of forage for livestock. Rangeland is a highly variable land type that includes native grassland, shrubland, or savanna sub-types. Even within these sub-types, species composition is divers and variable relating to differences in soil, climate, topography, and management history. The herbaceous species—grass and forbs—are most important to provisioning forage and this group of plants includes considerable species diversity with a large diversity of traits: photosynthetic pathway, lifespan, short and tall, water use efficiency, nutritional value, susceptibility to drought, ability to recruit into an open niche. Under a changing climate, species fitness to the new environment may be altered and/or the quantity, nutritive value, and timing of forage productivity may change. Species that become less fit to the new environment will decline while species better fit to the new environment will increase. The effect of climate change on rangeland is complex. The effect will depend on several factors such as whether a) the change is to temperature, precipitation, or both; b) it’s a directional shift in the average value, change in variability, change in synchronicity, or some combination; and/or c) the temporal span over which these changes occur. I review the literature to understand how changing climate, based on current thinking, may effect rangeland in terms of species composition, productivity, and nutritive value. Furthermore, I discuss what may be done to adapt to or mitigate these potential effects.