EP43B-0978
Multi-Source Remote Sensing to Observe Impacts of Fluctuating Management and Climate on Riparian Vegetation of the Rio Grande: 1935 to 2014
Thursday, 17 December 2015
Poster Hall (Moscone South)
Roy Petrakis1, Paul Tashjian1, Regina Dello Russo2, Bruce Thomson3 and Willem J D Van Leeuwen4, (1)Fish and Wildlife Service, Albuquerque, NM, United States, (2)Fish and Wildlife Service - Retired, Albuquerque, NM, United States, (3)University of New Mexico, Department of Civil Engineering, Albuquerque, NM, United States, (4)University of Arizona, Tucson, AZ, United States
Abstract:
Large rivers of the Southwestern United States are central to both ecological and human communities. Complex relationships exist between water policy, management, and natural ecosystems. The San Acacia Reach of the Rio Grande in central New Mexico, a 50 mile stretch from San Acacia to San Marcial, has experienced multiple management and climate fluctuations over the past 80 years, resulting in threats to riparian and aquatic ecosystems. These changes have included channelization of the river, reduced seasonal flooding due to upstream dams and conveyance channels, and varying river flows as a result of drought cycles. Understanding how the location and composition of vegetation has responded to these changes is essential in understanding the larger influence on the riparian vegetation which surrounds the river. This research used remote sensing data, land cover change analysis, GIS, and a review of the on-the-ground management decisions to accomplish the following goals: 1) determine how the channel has changed spatially over time, 2) determine the location and composition of vegetation change, and 3) determine potential linkages between management and the terrestrial and aquatic ecosystems. This research focused on four research periods which provide unique opportunities to observe a direct relationship between river management and land cover change. The periods are: 1) 1935 to 1962, 2) 1962 to 1987, 3) 1987 to 1999, and 4) 1999 to 2014. Initial results show increased invasive vegetation growth in response to early large scale, basin-wide changes in river management. Between 1962 and 1987, invasive forest/woodland land cover increased by more than 250%. However, as a result of restoration efforts over the past 25 years, combined with periods of increased precipitation and an aging ecosystem limiting new growth, native vegetation has responded and invasive vegetation growth has slowed. This has occurred despite a more constricted and incised river channel. Overall, the river has been greatly altered by years of natural and anthropogenic processes. Understanding the range of spatial and temporal response of vegetation to management may be the key to protecting it for many years to come.
