Pilot National Forest Reports
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Pilot National Forest Reports Contents Gallatin National Forest ......................................................................... 34 Helena National Forest ........................................................................... 50 Grand Mesa, Uncompahgre, and Gunnison National Forests ................ 68 White River National Forest ................................................................ 116 Coconino National Forest .................................................................... 134 Sawtooth National Forest ..................................................................... 162 Shasta-Trinity National Forest ............................................................. 189 Umatilla National Forest ...................................................................... 214 Ouachita National Forest ...................................................................... 230 Chequamegon-Nicolet National Forest ................................................ 240 Chugach National Forest ...................................................................... 270 33 Assessment of Watershed Vulnerability to Climate Change Gallatin National Forest April 2012 Prepared By: Joan Y. Louie Fisheries Biologist/GIS Analyst 34 R1 Regional Office, Missoula, Montana BACKGROUND The Gallatin National Forest (GNF) is located in southwestern Montana within the Northern Region (R1) of the U.S. Forest Service (USFS) and is part of the Greater Yellowstone Ecosystem, the largest intact ecosystem in the continental United States (fig. 1). The 1.8 million acre Forest contains more than 1,900 miles of fish-bearing streams and 700 high mountain lakes, and supports important, high-profile recreational fisheries. Figure 1—The Gallatin National Forest is located in southwestern Montana, within the Greater Yellowstone Ecosystem. 35 Gallatin National Forest Watershed Vulnerability Assessment, Northern Region (R1) PARTNERS Data were provided by: • The Montana Natural Resource Information System (NRIS) • Montana Bureau of Mines and Geology (MBMG) • U.S. Geological Survey (USGS) • University of Washington Climate Impacts Group (CIG) • Montana Fisheries Information System (MFISH) • U.S. Forest Service (USFS) R1 Geospatial Group • Ecoshare Assistance with the analysis was provided by: • Kerry Overton et al., Rocky Mountain Research Station • Ralph Martinez, Plumas National Forest • Jim Morrison, R1 Regional Office ASSESSMENT OBJECTIVES The objective of this project was to develop a reliable method to prioritize all HUC-6 watersheds within the GNF in order to focus forest resource conservation and restoration efforts. A watershed characterization process was first developed to assess the relative sensitivity of the watersheds to disturbance, based on various environmental parameters. A vulnerability assessment further prioritized watersheds using the Watershed Condition Framework, resources of value, and exposure (climate projections). The proposed analysis has been developed in part to address the USFS initiative in considering climate change in land management decisions. Current studies show climate change is occurring, but climate model projections are uncertain and models at common management scales are nonexistent. Therefore, alternative methods of examining the potential impacts of climate change and other environmental stressors are needed. While this initial framework was originally designed from a watershed perspective, the results can also have implications for terrestrial management, such as fire, rangeland, and wildlife management activities on the GNF. This process is intended to make it easy to update previous runs or examine other resources simply by rotating in the appropriate datasets. This project will also provide an example for other Forests in Region 1 to develop similar vulnerability assessments. SCALE OF ANALYSIS The scale of the analysis used in the GNF assessment was HUC-6 (12-digit) subwatersheds (fig. 2) and HUC-5 (10-digit) watersheds (fig. 3). 36 Gallatin National Forest Watershed Vulnerability Assessment, Northern Region (R1) Figure 2—Subwatersheds (HUC-6) on the Gallatin National Forest. Figure 3—Watersheds (HUC-5) on the Gallatin National Forest. 37 Gallatin National Forest Watershed Vulnerability Assessment, Northern Region (R1) CONNECTIONS TO OTHER PROJECTS AND ASSESSMENTS GNF Stream Temperature Modeling The objective of this project is to develop a broad-scale geographic information system (GIS) model to predict the effects of climate change on stream thermal regimes that in turn, provide the basis for estimating impacts on fisheries resources. A standardized approach was developed to collect and share temperature information among partner agencies and the public. The results will be used in conjunction with the GNF Watershed Vulnerability Assessment (WVA) to identify thermally sensitive habitats and vulnerable native fish populations, and to prioritize future restoration activities to mitigate the effects of climate change on aquatic resources. GIS analysis identified locations for deployment of stream temperature loggers in HUC-6 watersheds intersecting the Gallatin and Custer National Forests. A matrix was developed comparing stream size (y-axis) and elevation (x-axis). Multiple temperature deployment locations were chosen from each cell of the matrix across broad spatial scales (see fig. 4 for the Lower East Boulder River HUC-6 watershed). Approximately 100 stream temperature loggers will be deployed, which include 40 long-term/multi-year deployments and 60 short-term/annual deployments. The data collected will be used to develop a model to predict changes in stream temperature with respect to elevation, contributing area (stream size), and air temperature. The methods employed were developed by the Rocky Mountain Research Station. For a complete description, refer to the following Web site: http://www.fs.fed.us/rm/boise/AWAE/projects/stream_temp/multregression/methods.shtml E as t Bo ulde r Riv er h c l Dry Fork Creek u G t h ig Burnt Gulch Wr Canyon Creek Blakely Creek Figure 4—Temperature deployment locations within the Lower East Boulder River HUC-6 watershed. 38 Gallatin National Forest Watershed Vulnerability Assessment, Northern Region (R1) Watershed Condition Framework The Watershed Condition Framework (WCF) was included as one step in the process. The WCF established a nationally consistent method for classifying watershed condition and documenting improvements in watershed condition at the forest, regional, and national scales (U.S. Forest Service 2011). This process uses 12 indicators and 24 attributes to serve as surrogate variables representing fundamental ecological, hydrological, and geomorphic functions, and processes that affect watershed condition. The primary emphasis is on ecological processes and conditions that Forest Service management activities can influence. There are three watershed condition classes identified in this process: • Class 1 = Functioning Properly • Class 2 = Functioning at Risk • Class 3 = Functionally Impaired Watersheds considered to be Functioning Properly have ecosystem processes functioning within their range of natural variability. In general, the greater the departure from the natural pristine state, the more impaired the watershed condition is likely to be (USFS 2011). Climate Change Performance Scorecard The Climate Change Performance Scorecard is the Forest Service’s tracking tool to assess progress in integrating climate change considerations into programs, plans, and projects. It is composed of 10 performance elements, with a national goal of 100 percent of Forests/Grasslands to achieve a “Yes” rating on 7 of the 10 elements by FY 2015. One of these elements is a vulnerability assessment, which the WVA would fulfill. Forest Landscape and Rapid Assessments The WVA would not replace these assessments but can help validate priorities being identified in these assessments. 39 Gallatin National Forest Watershed Vulnerability Assessment, Northern Region (R1) WATERSHED VULNERABILITY ASSESSMENT PROCESS Figure 5—The Gallatin National Forest Watershed Vulnerability Assessment Model. The assessment consists of several different types of information (added and removed as necessary) to identify vulnerable watersheds. Geophysical/Sensitivity Characterization The first step of the WVA process, the geophysical/sensitivity characterization, was the most time- consuming. As interdisciplinary team (fish biologist, hydrologist, and soil scientist), identified the dominant physical processes and features of the watershed that affect ecosystem function and condition. Identifying which watersheds are the most geophysically reactive can indicate how much a watershed responds to disturbances such as floods, drought, intense precipitation, and fires. The datasets determined to be most important for the watershed characterization were soils, geology, hydrology, terrain, and groundwater. The initial run of this analysis utilized pre-existing datasets (often outdated and of lower resolution and accuracy). These datasets include the GNF Soil Survey (slope classes, surficial geology, and shallow groundwater) and datasets derived from the National Hydrography Dataset, National Elevation Dataset, and R1 VMap (water yield, high flows, and low flows). After this initial run, the team met again to evaluate the results and determine which watershed characteristics were most important. The second run of the analysis included newer datasets developed for the analysis. The state surficial