Restoration Ecology Overiew Restoration has been an important component of park management in the Pacific Northwest for the past twenty-five years. Early restoration programs focused on the subalpine zone where recreational use had caused extensive networks of informal trails and campsites. Initially, revegetation of these sites utilized both direct seeding and transplanted "plugs" of native species from adjacent undamaged plant communities. However, it soon became apparent that the number of plugs needed to restore damaged sites exceeded the number that could be salvaged from pristine areas without significantly degrading them. By the early 1980s, all three parks had built greenhouse facilities and were propagating native species for subalpine restoration. Over the last decade, restoration programs in North Cascades and Olympic have expanded into low elevation areas. Olympic has been restoring coastal areas near Sand Point, and North Cascades has initiated erosion control and restoration along the Ross Lake shoreline. Although Mount Rainier's program has remained concentrated in the subalpine zone, it has expanded to include restoration of aquatic ecosystems. Experimental removal of introduced fish was initiated in 1994 to investigate its effectiveness in restoring amphibian and invertebrate populations altered by the presence of the non-native fish. The largest and most comprehensive restoration program still lies ahead - restoration of the Elwha River ecosystem in Olympic National Park. The goal of restoration in all three parks is to restore functioning ecosystems on damaged sites. In most instances, a reference stand is selected from an adjacent undamaged area with similar habitat characteristics. Detailed records are kept on plant and soil treatments used on each restored site, and many sites are monitored to evaluate the effectiveness of restoration efforts. Most monitoring has focused on cover or density of plant species and has documented high rates of transplant survival. Research is now needed to refine methods and to evaluate whether functioning ecosystems have been re-established. Soils and Biota Background Historically, damaged sites in NOCA and OLYM have minor levels of erosion, and the manipulation of substrates during restoration efforts is minimal. Sites were scarified and sometimes amended with peat to restore organic matter content. Only recently, along Ross Lake has NOCA started to salvage soil (silt loam to scree) from the lake bottom to bring sites up to grade. However, at MORA severe erosion has long necessitated aggressive treatment of restoration sites. Prior to revegetation of these areas, sites are stabilized and filled to grade with soil, rock, and gravel to restore original topographic patterns. Sites less than 12" deep are filled with soil purchased from outside the park. The soil is custom mixed to match the organic matter content, soil texture, and pH of native soils, and it is steam-sterilized to reduce invasion by exotic plant species. On sites greater than 12" deep, a layer of gravel or rocks is added prior to the addition of soil. Generally, fertilizers are not used in any park because they may facilitate establishment of exotic species or reduce establishment of mycorrhizae. Park Focus: MORA, NOCA, OLYM Research Needs What invertebrates are present in undisturbed sites? What species are present in restored sites? Are there key species that can be used to assess the condition of restored sites? What role do soil treatments play in the success of restoration projects? Is the addition of peat the best treatment of sites with minimal soil loss? What is the minimum effective level of soil treatment on restoration sites? Should soil treatment differ between coastal, lakeshore, and subalpine sites? What affect does steam pasturization have on soil? Does this destroy native biota along with introduced seeds and pests? If substrates are not amended, can plants be expected to survive? Specifically, are plants failing to thrive at Cascade Pass (NOCA) because soil was never added to eroded sites? Rev. 9/2000 Mycorrhizae Background Park Focus: MORA, NOCA, OLYM Research Needs How do mycorrhizal associations change with site? How many mycorrhizal species are found in our native plant communities? During which stage of plant development does mycorrhizal inoculation need to occur? Are mycorrhizal species associated with seedling establishment the same as for mature communities? How do our restoration practices affect or limit mycorrhizal infection of plants or habitats? How does the size of the restoration site affect mycorrhizal innoculation? How does inoculation affect short-term versus long-term success of restoration (i.e., are growth rates/root and shoot greater over the long-term)? What are effective methods of site inoculation? What is the genetic diversity of mycorrhizal species? Should we consider innoculation of sites or during propagation activities? Could our greenhouse operations be the source of new mycorrhizal species to field sites? Rev. 9/2000 Seed Production and Plant Conditions Background Park Focus: MORA, NOCA, OLYM Research Needs What are the germination and viability rates of species we propagate? How do these rates change over time with seed storage? What are natural levels of seed rain in the plant communities of our sites? What species and quantities of seeds are stored in seed banks? Does the use of mulches limit seed rain to restoration sites? How do mulches influence seed germination? How do mulches affect soil temperatures, soil mositures, soil nitrogen levels, and mycorrhizae? Should we use different types of mulches at different elevations or different sites within each park? What volumes of seeds are optimal for revegetation? What species are most successfully seeded? What is the condition of plants in restored sites? Are these species reproducing? Are root systems spreading? How does watering influence plant survival? How long is watering needed to substantially increase survival or growth rates? Rev. 9/2000 Greenhouse Practices Background Park Focus: MORA, NOCA, OLYM Research Needs Do we introduce non-native invertebrates to restoration sites on greenhouse propagated plants? How can horticultural practices improve field survival of greenhouse plants? What are the effects of greenhouse preconditioning on field performance of native plants? What are the effects of introduced soil components (e.g., perlite, vermiculite, pumice, sand) on native soil and invertebrates, mycorrhizae, water movement between native and imported soil, soil freezing and movement, root behavior? Rev. 9/2000 Genetic Diversity Background Park Focus: MORA, NOCA, OLYM Research Needs How does genetic diversity change across elevation, habitat, or distance gradients? What adaptive variations do species used in restoration exhibit? How do our restoration practices alter natural patterns of diversity? At NOCA, what are the genetic diversity patterns of low-elevation plant species, used in restoration, along the Ross Lake shoreline? Can species be moved across the lake? How far should plant materials be moved up and down the lake? Recent Research Rochefort, R. M. 1995. Ecology and conservation of heather in Mount Rainier National Park. Ph.D. dissertation. University of Washington, Seattle, WA. 112 p. Rev. 9/2000 Species Used in Restoration
Rev. 9/2000 Ecosystem Changes Resulting from Dam Removal Background The Elwha and Glines Canyon Dams are located on the Elwha River, which flows on the Olympic Peninsula of northwestern Washington State. Elwha Dam was completed in 1913 at river mile (RM) 4.9, and includes a 108-foot-high concrete gravity section, gated spillways on both abutments, and a powerhouse with four generating units rated at a combined capacity of 14.8 megawatts (MW). Glines Canyon Dam was completed in 1927 at RM 13.4 and includes a 210-foot-high concrete thin arch section, a gated spillway on the left abutment, a thrust block on the right abutment, and a powerhouse with a single generating unit rated at 13.3 MW. Elwha Dam impounds Lake Aldwell, which has a surface area of 267 acres and a storage capacity of 8,100 acre-feet at elevation of 197.0 feet. Glines Canyon Dam impounds Lake Mills, which has a surface area of 415 acres and a storage capacity of 40,500 acre-feet at elevation of 590.33 feet. Both dams were acquired by the Federal government on February 29, 2000. They are being operated by the Bureau of Reclamation, with National Park Service oversight, until they are removed. The Elwha River ecosystem and native anadromous fisheries will be restored through the removal of both dams and implementation of fisheries restoration and revegetation. The dams were installed without fish passage facilities on the Elwha River, so they obstruct upstream fish migration beyond the first 4.9 miles of the river. Before the dams were built, the Elwha River produced an estimated 380,000 anadromous (migrating) salmon and trout. Salmon and steelhead once filled over 70 miles of mainstem and tributary habitat in the Elwha. Their carcasses fed more than 22 species of wildlife and supplied the entire aquatic ecosystem with organic material, phosphorus and nitrogen. The construction of Elwha Dam blocked access to 93% of Elwha River habitat for these anadromous fish and began what became a precipitous decline in the native populations of all 10 runs of Elwha salmon and sea-going trout. Now, populations of primarily hatchery fish return to only the 4.9 miles of river below the Elwha Dam to spawn in crowded, unnatural and poor quality conditions. Both the terrestrial and aquatic ecosystems are less productive and varied as a result. Park Focus: OLYM Research Needs Aquatic Invertebrates: Inventory aquatic invertebrates in upper (above Glines Dam), middle (between the two dams) and lower (below Elwha Dam) river. Vegetation: Inventory riparian plant communities from the river mouth upstream to the historic limit of anadromous fish migration. Water Quality: Compile existing information regarding temperatures, dissolved oxygen, etc., and initiate monitoring program for the upper, middle and lower river. Sediment Transport and Stream Channel Morphology: Describe substrate composition, depth, channel width across representative transects from Glines Dam to the river mouth. Marine and Estuarine Resources: Map the physical and biological features of the estuary and reservation beaches near the river mouth. Wildlife: Conduct population surveys for osprey, red-tailed hawk, bald eagles, etc. Radio-tag elk to determine seasonal movements and migration patterns within river basin. Rev. 9/2000
research-catalog/restoration.htm Last Updated: 05-Sep-2000 |