180 likes | 322 Views
Developing a Decision Support System for Prioritization of Wetland Restoration in Coastal Louisiana. Steve Hartley U.S. Geological Survey, National Wetland Research Center, Lafayette, LA Nicholas Enwright Five Rivers Services, LCC, Lafayette, LA. Introduction.
E N D
Developing a Decision Support System for Prioritization of Wetland Restoration in Coastal Louisiana Steve Hartley U.S. Geological Survey, National Wetland Research Center, Lafayette, LA Nicholas Enwright Five Rivers Services, LCC, Lafayette, LA
Introduction • From 1998 to 2004, the Gulf of Mexico coastline experienced a net loss of 250 km2 in wetlands per year (Stedman and Dahl, 2008). • 1/3 of the total net wetland loss along the Gulf of Mexico coastline (U.S. Geological Survey, 1995) • From 1956 – 2006, Barras et al. (2008) found a total land loss of 3,493.9 km2 with an average loss of 69.7 km2 per year.
Wetland Restoration • Essential to slowing wetland loss in coastal Louisiana • Utilize the best available technology and data to make informed and forward-thinking decisions • Over the last ten years, GIS has become increasingly utilized for wetland restoration planning
Objective • Work with U.S. Fish and Wildlife Service to develop a decision support system that can combine geospatial datasets to prioritize future wetland restoration projects Goals: • Build a highly flexible application • Make application accessible for users with limited GIS experience • Develop automated report generation functionality for analysis of results
Coastal Louisiana • The application was developed for coastal Louisiana.
Methods • Application is built for ArcMap 10 • Python 2.6 (ArcPy module) was used for geoprocessing • WxPython 2.8 (Python add-on) was used for user interface • Reportlab 2.5 (Python add-on) and ArcPy module were used for report generation • Application is run outside of ArcMap using a python script • All geoprocessing occurs “behind the scenes”
Available Variables • Distance from shoreline • Distance from fastlands • Distance from rivers • Distance from refuges • Essential habitat • Distance from essential habitat • Sea level rise/subsidence • Percent land change (1985-2009) • Projected land/water 2050 • Land/water edge 2008 • Land cover • Elevation • Vegetation (2007) • Geology • Soils (hydric or surface texture) • Geographic bounds
Conceptual Model • Steps: 1) Decide variables to use 2) Assign weights to variables (total weight = 100) 3) Standardize variables to values from zero to nine
Log Files • Created to document settings used for prioritization model
User Interface • Variables • Weights • Reclassification • Metadata • Pre-existing Logs • Scenarios • predefined • development • Cell size • Extent • Display results
Variable Reclassification • Default reclassifications • Mostly based on natural breaks (Jenks) for coastal Louisiana • Other data (i.e. soils, geology, land cover, etc.) based on professional judgment with a goal of sustainability. • Variables should be reclassified by user to fit the desired goal of prioritization
Results • .mxd is created • Basemap • Results raster • Weighted and standardized variables • Original input variables • Aerial imagery
Additional Tools • Report Generation: • Compare model scores for projects with maps • Compare multiple model scores for projects Requires: 1) model result dataset(s) 2) polygon .shp for projects 3) Field to be used for project name • Mosaic to new raster
Report Generation Use zonal statistics to find mean “scores” for project boundaries Comparing multiple “scenarios” for projects Compare model scores for projects
What’s Next? • Development of standardized scenarios • U.S. Fish and Wildlife Service • Gulf Coast Joint Venture • Implementation of the application as part of process of wetland restoration planning
Conclusion • Slowing the rapid rate of wetland loss in coastal Louisiana is a priority for scientists, policy makers, and land managers in the region • We have developed a highly flexible application to assist in wetland restoration planning • More work needs to be done to develop standardized scenarios prior to implementation of the application • Until standardized scenarios are developed the tool requires informed input from the user
Questions? Contact info: Steve Hartley U.S. Geological Survey, National Wetland Research Center Email: steve_hartley@usgs.gov Nicholas Enwright Five Rivers Services, LLC U.S. Geological Survey, National Wetland Research Center Email: enwrightn@usgs.gov