California Department of Fish and Wildlife

Management Tools for Landscape–Scale Restoration of Ecological Functions

Oblique view of the historical Delta ovierlaid on moder aerial imagery

Oblique view of the historical Delta overlaid on modern aerial imagery in Google Earth
Photo by Allison Whipple et al, Aquatic Science Center

Location: Sacramento–San Joaquin Delta

Total Project Cost: $875,000 (Ecosystem Restoration Program)

Partners: Aquatic Science Center, U.S. Geological Survey, University of California Davis, University of Washington, Delta Science Program, PRBO Conservation Science, CDFW, UC Berkeley, Delta Stewardship Council

Project Summary: Restoration goals for the Sacramento-San Joaquin Delta focus on the establishment of large areas of interconnected habitats. However, the fundamental issue of how to integrate this large-scale thinking with small-scale, on-the-ground restoration projects remains.

The project is designed to answer the question of how restoration of major habitat types can best proceed in order to achieve greater ecological function in the Delta. The objectives are centered on providing tools needed to help establish a practical guiding vision of landscape-scale restoration. These tools can be used by agencies, managers and restoration practitioners to design, implement, and evaluate restoration investments so that they are more effectively integrated with longer term landscape restoration strategies and provide the greatest benefits with the least amount of cost. These tools include refined conceptual models of habitats, landscape-scale conceptual models, and design principles and target metrics. Furthermore, project objectives include the development of landscape metrics, such as connectivity among and between habitats, linked to the expected ecological functions provided by landscape characteristics. The project will help meet this ERP objective by incorporating knowledge of how habitats are arranged at the landscape scale, what physical processes are related, and what ecological functions they provide. The project will provide a basis for ERP restoration project selection, design, and performance evaluation that is currently not available.

Perhaps equally significant, this project addresses the Ecological Processes goal by providing information on how the rehabilitation of natural processes can most effectively proceed in order to provide needed Delta ecological functions. Overall, the project will establish linkages between landscape pattern and process. The project objectives include addressing uncertainties in current habitat conceptual models and establishing landscape-level conceptual models, which will facilitate establishment and maintenance of hydrologic and hydrodynamic regimes, increased estuarine productivity, creation and maintenance of channel morphology and shallow water habitat, reestablishment of floodplain processes, and the enhancement of pre-1850 river channel forms. Linking of specific ecological functions to landscape-scale restoration will also support the establishment of self-sustaining populations of many native species.

Specifically ASC and collaborators will 1) quantify landscape-scale metrics based on historical landscapes, 2) develop an understanding of historical ecological functions and compare them to contemporary ones, 3) refine conceptual models of Delta ecological function, 4) develop restoration design principles and guidelines based on this new understanding, and 5) present explicit landscape illustrations and other visualizations to be used to create guiding images for the future Delta. This project has been strategically designed in close conversation with local scientists and agency managers to complement current restoration planning efforts and to provide the specific tools that managers need for landscape-level restoration of ecological functions.

historical ecology conceptual diagram

This conceptual diagram depicts the context of historical ecology within environmental planning and management (Whipple et al 2012). Historical data and study of the physical landforms of an area provide the information needed to understand the historical ecology of an area (Synthesis of historical landscape pattern and process; blue box). This baseline information can then be used to support interpretation of ecological functions (green box) and development of landscape planning and management strategies (yellow box; e.g., conceptual models, restoration principles, and target metrics). These steps will be furthered in subsequent studies. Importantly, the larger context of this study is its informing a collective vision of the future Delta (pink box).

Report: Sacramento-San Joaquin Delta Historical Ecology Investigation: exploring pattern and process (PDF)

For additional information visit San Francisco Estuary Institute’s website for the Sacramento-San Joaquin Delta Historical Ecology Study.