SYMP 23-4 - Management and restoration of multiple ecosystem services in Great Salt Lake wetlands: Challenges and opportunities

Friday, August 11, 2017: 9:40 AM
D135, Oregon Convention Center
Karin M. Kettenring1, Rebekah Downard1,2, Christine Rohal1 and Aubin Douglas1, (1)Watershed Sciences, Utah State University, Logan, UT, (2)Utah Division of Water Quality

Wetlands, particularly those in the arid west where wetlands are scarce, are valued for the ecosystem services (ES) they provide to society. The wetlands of the Great Salt Lake—the largest wetland complex in the region—sustain continentally important migratory bird populations valued by birdwatchers (cultural ES), produce abundant waterfowl prized by duck hunters (provisioning ES), and regulate hydrologic, nutrient, and atmospheric cycles that directly affect the health of Utah residents (regulating ES). Two major threats to these wetlands are the focus of restoration and management: declining water availability due to upstream water diversions and the invasion of non-native Phragmites australis that has diminished bird habitat. We address the following questions to improve management and restoration for multiple ES: (Q1) what are the differing ES goals of wetland managers representing federal, state, and private entities? (Q2) what are drivers of and relationships among these ES in restored and managed wetlands? and (Q3) how might available data sources on wetland condition (the focus of regulatory agencies) and ecosystem function (often the focus of scientists) guide ES restoration approaches and monitoring? We answer these questions by integrating data from managers surveys, a 50 wetland condition assessment, and large-scale, multi-year Phragmites control experiments.


(Q1) Managers’ goals were strongly tied to their overall missions—to maintain waterfowl habitat for conservation or hunting—but were broadly interested in supporting other bird guilds and wildlife viewing. (Q2) In the restoration experiments, plant community recovery was driven by herbicide application timing and the extent of growing season flooding. In the wetland condition assessment sustained flooding in wetlands—made possible with the use of impoundments that decreased the frequency and magnitude of drought—resulted in a higher proportion of native, monocot, and obligate wetland plant species that support large-bodied wildlife. Furthermore, this flooding potentially attenuates peak flood flows and minimizes dust generation. Fluctuating water levels in unimpounded wetlands maintained a diversity of wetland plant communities that support a broad array of bird species while creating the anaerobic/aerobic interface required to efficiently decrease nutrient loads. (Q3) The drivers of wetland condition were most strongly driven by depth and duration of flooding while ecosystem function was related to an array of soil, hydrologic, and disturbance factors. Ecosystem function, as opposed to wetland condition, was more strongly related to ES. Ultimately, to maintain and restore ES in wetlands, it will be imperative to prioritize areas with the required hydrologic conditions.