Responses to climate change in hot desert ecosystems: connecting local to global scales

TitleResponses to climate change in hot desert ecosystems: connecting local to global scales
Publication TypeConference Paper
Year of Publication2011
AuthorsPeters DC
Conference Name96th Ecological Society of America Annual Meeting
Date Published08/2011
PublisherEcological Society of America
Conference LocationAustin, TX
ARIS Log Number265023

The consequences of connectivity in resources, propagules, and information to the interplay between drivers and responses across scales can result in ecological dynamics that are not easily predicted based on local drivers. Three major classes of connectivity events link local ecological dynamics with broader scale drivers. These events differ in initial driver characteristics (intensity, spatial extent, duration), rate of change in response through space, and the relative importance of driver characteristics versus ecological properties and land cover through time. As a result, the impacts of drivers on ecological systems can be synchronized, attenuated or amplified through time and space. Here, I examine how these three classes can interact during the course of a climatic event to result in surprising ecological responses, and a potential state change reversal in the largest desert of North America. A hurricane in 2008 resulted in unusually large amount of summer rainfall, and resulted in a broad-scale recruitment of perennial grasses in degraded shrublands. Successive years of average and below-average rainfall amplified the growth and spatial propagation of grasses via plant-soil feedbacks at the scale of individual plants. Continued interactions across scales are expected to push the system towards a new state codominated by grasses and shrubs. These complex cross-scale dynamics are not unique to this system, and suggest that effective predictions of future dynamics will require a consideration of changing drivers and landuse across scales that include both contiguous and non-adjacent locations.