Literature Survey: Restoration of Aquatic Habitats – Northwest Territories

Citation: Polster Environmental Services Ltd. (2014, March). Literature Survey: Restoration of Aquatic Habitats – Northwest Territories. Prepared for Morag McPherson, Fisheries Protection Biologist, Fisheries and Oceans Canada, Yellowknife, NT.

Prepared by: Polster Environmental Services Ltd., 6015 Mary Street, Duncan, BC, V9L 2G5
Prepared for: Morag McPherson, Fisheries Protection Biologist – FCSAP, Fisheries and Oceans Canada, 5204–50th Ave., Suite 301, Yellowknife, NT
Date: March 2014

This 71-page document reviews 137 articles on restoration of aquatic habitats in the Northwest Territories, with a focus on riparian restoration, wetland restoration, and soil bioengineering. The focus is Baker Creek at the Giant Mine, Yellowknife, NWT. The full PDF is available for download above. An annotated selection of the reviewed literature follows.

1.0 Introduction

Effective restoration is an integral part of any remediation project. Restoration treatments are often not considered until after the remedial work is complete and the site is "cleaned up." If a riparian area is within a remediation project, restoration becomes even more essential since riparian areas provide important ecological functions, goods and services.

This report presents the results of a literature search that was conducted for Fisheries and Oceans Canada, Northwest Territories on restoration of aquatic habitats. Details of the methods employed in the search as well as the results are provided below.

2.0 Methods

Databases accessible through Google, Google Scholar and Mendelay search engines were employed to locate relevant references for this document. In addition, materials available at Polster Environmental Services Ltd. were studied. Additional references were located from Polster Environmental Services library, citations in selected papers and from recommendations from other researchers. A focus on methods and information about Canada and the United States was applied to limit the tremendous amount of data available. However, some articles of very pertinent topics from other countries were included. Key search words were "riparian restoration", "wetland restoration" and "soil bioengineering". Using search words such as "boreal" and "northern" limited the search greatly and was soon abandoned. Abstracts were downloaded and reviewed and then the most relevant papers were listed.

3.0 Results: Annotated Bibliography

A total of 137 articles are listed including a wide range of topics. Some topics were very specific, i.e. the interactions of salmon and bear in riparian forests in Alaska (Helfield and Naiman 2006) to general articles about the importance of riparian restoration (Laub et al. 2009). The materials specific to northern Canada were very limited. The majority of materials were from American sources. Of critical interest were several articles on the importance of wetlands to help mitigate climate change (Nilsson et al. 2013). It is hoped that this literature review will be helpful in improving riparian restoration in the Northwest Territories.

Anderson, J. T., Osbourne, J. D., & Ward, R. L. (2004). Integrating riparian restoration to promote wildlife habitat with natural stream channel design on mine land habitats. Proceedings of the National Meeting of the American Society of Mining and Reclamation, 21, 47–73.
The role of natural streams and associated riparian habitat in structuring vertebrate communities is an important wildlife management issue in human-impacted environments. Many studies have illustrated the value of healthy riparian ecosystems in providing basic habitat requirements for a broad array of vertebrate taxa. In regions where coal mining is widespread and vital to state and local economies, it is important to address the effects of different mining practices on riparian ecosystems. Two major negative impacts of mining on natural streams and stream corridors is the alteration of physical characteristics of the stream itself and fragmentation of riparian habitat. Natural stream channel design has become a popular means of mitigating for impacts to stream channel structure; however, less emphasis has been placed on the science of creating riparian corridors to connect riparian areas fragmented by human impacts such as mining. This paper provides a background and review of literature regarding the importance of riparian ecosystems to vertebrates, the effects of mining on vertebrate populations in riparian habitats, and the use of natural stream design in riparian restoration.

Audet, J., Elsgaard, L., Kjaergaard, C., Larsen, S. E., & Hoffmann, C. C. (2013). Greenhouse gas emissions from a Danish riparian wetland before and after restoration. Ecological Engineering, 57, 170–182.
Restoration of riparian wetlands often aims at increasing the removal of nitrogen and phosphorus by re-establishing the hydrological connectivity between the stream and the surrounding floodplain. However, the geochemically reduced soil conditions in the newly restored area may favor the emission of greenhouse gases (GHG) such as nitrous oxide (N2O) and methane (CH4). Data collected during the first year after restoration revealed spatially and seasonally variable N2O emissions. The re-establishment of a high groundwater level induced a significant increase in CH4 emissions, while ecosystem respiration at restored sites decreased or remained stable.

Bernhardt, E.S. and M. A. Palmer. (2011). River restoration: the fuzzy logic of repairing reaches to reverse catchment scale degradation. Ecological Applications, 21, 1926–1931.
River restoration is an increasingly common approach to reverse past degradation of freshwater ecosystems. While the practice of river restoration has grown exponentially, there has been little empirical evaluation of whether restoration projects achieve the legally mandated goals of improving the structure and function of streams and rivers. New efforts to evaluate river restoration projects using channel reconfiguration are finding little evidence for measurable ecological improvement. Designed channels may have less-incised banks and greater sinuosity than degraded streams they replace, but reach-scale efforts do not appear to be effectively mitigating the physical, hydrological, or chemical alterations responsible for loss of sensitive taxa and declines in water quality.

Bernhardt, E. S., Sudduth, E. B., Palmer, M. A., et al. (2007). Restoring Rivers One Reach at a Time: Results from a Survey of U.S. River Restoration Practitioners. Restoration Ecology, 15, 482–493.
Despite expenditures of more than 1 billion dollars annually, there is little information about project motivations, actions, and results for the vast majority of river restoration efforts. Confidential telephone interviews with 317 restoration project managers found that ecological degradation typically motivated restoration projects, but post-project appearance and positive public opinion were the most commonly used metrics of success. Less than half of all projects set measurable objectives. Projects classified as highly effective were distinct in that most had significant community involvement and an advisory committee.

Beschta, R. L., & Ripple, W. J. (2010). Recovering Riparian Plant Communities with Wolves in Northern Yellowstone, USA. Restoration Ecology, 18, 380–389.
Gray wolves (Canis lupus) were extirpated from Yellowstone National Park in the 1920s, during which wild ungulates extensively used woody browse species in the upper Gallatin and northern winter ranges. Following reintroduction of wolves in the mid-1990s, cottonwood (Populus spp.) recruitment was occurring for the first time in several decades, and heights of young willow and cottonwood had begun to increase. Results are consistent with the reestablishment of a tri-level trophic cascade involving wolves, ungulates, and riparian vegetation.

Bolton, S. M., & Shellberg, J. (2001). Ecological Issues in Floodplains and Riparian Corridors. Final White Papers.
Developed as part of Washington State's Aquatic Habitat Guidelines program, this white paper addresses the current understanding of impacts of development and land management activities on aquatic habitat, and potential mitigation. Topics covered include over-water structures, water crossings, channel design, marine and estuarine shoreline modification, dredging, and ecological issues in floodplain and riparian corridors.

Borders, B. D., Pushnik, J. C., & Wood, D. M. (2006). Comparison of leaf litter decomposition rates in restored and mature riparian forests on the Sacramento River, California. Restoration Ecology, 14, 308–315.
One of the largest riparian restoration projects in the United States is currently taking place in California on the Sacramento River, where nearly 2,000 ha have been revegetated with native riparian species. Leaf litter decomposition rates measured over one year in six restored riparian forests (4, 7, and 9 years old) and two mature remnant forests showed no significant differences in annual decay rates among forest ages, suggesting that functionally equivalent processes of leaf litter decomposition occur in both restored and naturally established forests.

Brookshire, E.N.J., Kauffman, J. B., Lytjen, D. and Otting, N. (2002). Cumulative Effects of Wild Ungulate and Livestock Herbivory on Riparian Willows. Oecologia, Vol. 132, No. 4, pp. 559–566.
Effects of wild ungulates (deer and elk) and domestic sheep on two common willow species in a montane northeast Oregon riparian zone were studied. Willows inside herbivore exclosures responded with pronounced increases in height, crown area, and basal stem diameters while browsed plants outside exclosures stayed constant or declined. Results suggest that even relatively light levels of domestic livestock grazing, when coupled with intense wild ungulate browsing, can strongly affect plant structure and limit reproduction of riparian willows.

Bump, Joseph K. et al. (2009). Large Herbivores and Aquatic-Terrestrial Links in Southern Boreal Forests. Journal of Animal Ecology, Vol. 78, No. 2, pp. 338–345.
Long-term study of the moose (Alces alces) population in Isle Royale National Park provides an opportunity to examine patterns of resource flux from aquatic to terrestrial habitats over 50 years. Results suggest that moose transfer significant amounts of aquatic-derived nitrogen to terrestrial systems. Aquatic foraging by moose and moose carcass locations are significantly clustered at multiple scales, indicating that grey wolves and moose can create concentrated areas of resource transfer due to clustered predation and foraging patterns.

Burnett, R. D., Gardali, T., & Geupel, G. R. (2005). Using songbird monitoring to guide and evaluate riparian restoration in salmonid-focused stream rehabilitation projects. U.S. Forest Service General Technical Report PSW, 191, 533–536.
A restoration effort focused on reducing stranding and improving passage of anadromous fish along lower Clear Creek, California was monitored using multi-faceted songbird monitoring. Songbird monitoring can (1) measure the effectiveness of restoration; (2) provide necessary feedback for adaptive management; (3) guide restoration design; (4) be cost effective; and (5) provide education and outreach opportunities.

Buron, Timothy, Kretsinger, Carl. (1989). Restoration of severely eroded streambanks using tree revetments and willow revegetation on Diamond Creek, Caribou County, Idaho. Practical Approaches to Riparian Resource Management: An Educational Workshop, May 8–11, 1989, Billings, Montana, BLM.
For most Intermountain Region streams, loss of stable riparian vegetation initiates a sequence of stream erosion resulting in development of steep, unstable cutbanks. As stable willow and sedge communities are altered to less stable vegetation types, natural resistance to bank erosion is reduced, contributing to sedimentation and a shallower, wider water column, which represents a significant reduction in salmonid habitat quality.

Capon, S. J. et al. (2013). Riparian Ecosystems in the 21st Century: Hotspots for Climate Change Adaptation? Ecosystems, 16, 359–381.
This synthesis suggests that, in the absence of adaptation, riparian ecosystems are likely to be highly vulnerable to climate change impacts. However, given the critical role of riparian ecosystem functions in landscapes, considerable means, motives and opportunities for strategically planned adaptation to climate change also exist. The need for planned adaptation of and for riparian ecosystems is likely to be strengthened as the importance of many riparian ecosystem functions, goods and services will grow under a changing climate.

Christian-Smith, J., & Merenlender, A. M. (2010). The disconnect between restoration goals and practices: A case study of watershed restoration in the Russian River Basin, California. Restoration Ecology, 18, 95–102.
Despite over $47 million spent on restoration in the Russian River basin, dominant forms of restoration are limited in scope to small-scale projects that focus on technical solutions to site-specific problems. The majority of restoration efforts are devoted to road repair, riparian stabilization, and in-stream structures, accounting for 62% of all projects. These types of projects do not address the broader social drivers of watershed change such as land and water uses.

Collins, K. E. et al. (2013). The effectiveness of riparian "restoration" on water quality: a case study of lowland streams in Canterbury, New Zealand. Restoration Ecology, 21, 40–48.
In New Zealand, around half of the lowland water bodies do not meet water quality standards. A paired-catchment design evaluating riparian plantings on water quality of lowland streams found equivocal benefits: improvements in dissolved oxygen and turbidity, but no changes in other variables. Results suggest that even narrow planted buffer strips may be effective in improving some water quality parameters, though insufficient buffer width limited outcomes.

Craig, L. S., Palmer, M. A. et al. (2008). Stream restoration strategies for reducing river nitrogen loads. Frontiers in Ecology and the Environment, 21, Issue 6, 529–538.
Small streams (1st–3rd order) with considerable N loads delivered during low to moderate flows offer the greatest opportunities for N removal through restoration. Suggested approaches increase in-stream carbon availability, contact between water and benthos, and connections between streams and adjacent terrestrial environments. Stream restoration alone is not appropriate for compensatory mitigation and should be seen as complementary to land-based best management practices.

Dosskey, M. G. et al. (2010). The Role of Riparian Vegetation in Protecting and Improving Chemical Water Quality in Streams. JAWRA Journal of the American Water Resources Association, 46, 261–277.
This review summarizes major processes by which riparian vegetation influences chemical water quality in streams, and how these processes vary among vegetation types. Riparian vegetation influences stream water chemistry through diverse processes including direct chemical uptake and indirect influences such as supply of organic matter to soils and channels, modification of water movement, and stabilization of soil. The degree to which stream water quality can be managed through vegetation management remains to be clarified.

Dynesius, Mats et al. (2004). Intercontinental Similarities in Riparian-Plant Diversity and Sensitivity to River Regulation. Ecological Applications, 14, No. 1, pp. 173–191.
Comparison of riparian plant communities response to river regulation on two different continents (boreal parts of North America and Europe) found that both riparian plant-species diversity along free-flowing rivers and the response to different kinds of flow regulation were similar between the continents. The similarity in the response to regulation between the continents suggests that general guidelines for rehabilitation of degraded boreal rivers are a realistic goal.

France, R.L. (1997). Macroinvertebrate Colonization of Woody Debris in Canadian Shield Lakes following Riparian Clearcutting. Conservation Biology, 11, No. 2, 513–521.
Clear-cut logging of boreal riparian forest in northwestern Ontario, Canada resulted in a dramatic shift from dominant conifers to regrowth composed largely of deciduous trees and reduced allochthonous inputs of small woody debris to lake littoral zones by over 90%. Colonization rates of woody debris by macro-invertebrates did not differ between coniferous and deciduous species, indicating that macro-invertebrates in these boreal lakes are opportunistic colonizers of woody debris, probably for its use as either a biofilm substrate or a predation refuge.

Fullerton, A. H. et al. (2006). Regional patterns of riparian characteristics in the interior Columbia River basin, Northwestern USA: applications for restoration planning. Landscape Ecology.
Riparian areas in agricultural and urban areas were significantly narrower (~30 m, median) than those in forested or shrub/grass areas (~70 m). The largest proportion of modified riparian areas occurred in low-gradient streams with floodplains in semi-arid ecoregions. Riparian vegetation in these areas is unlikely to provide adequate in-stream functions, making them a natural starting point for restoration prioritization.

Additional References (from full PDF)

The full 71-page document contains 137 annotated references covering: riparian and wetland restoration; soil bioengineering for slopes and streambanks; boreal and northern Canada restoration; climate change and riparian ecosystems; soil seed banks and vegetation succession; fish habitat and salmonid restoration; monitoring methodologies; and watershed-scale restoration planning. See the PDF download for complete bibliography including works by Polster, D.F. on soil bioengineering for riparian restoration (1999) and successional reclamation (1989).

Websites Referenced

Ducks Unlimited: a variety of easy to understand information on wetlands, some information specific to NWT: https://www.ducks.ca/places/yukon-northwest-territories/
Wetlands Alberta: fact sheets and best management practices about boreal wetland types including swamp, fens, open water, marsh, restoring lost wetlands and value of wetlands: https://www.wetlandsalberta.ca/general-public/
Government of Yukon: current wetland classification standards: https://yukon.ca/en/yukon-wetland-classification-standards
SER Primer on Ecological Restoration, SER 2004: SER International Primer on Ecological Restoration (PDF)