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173
Standards for ecologically successful river restoration.
- J. Ecol.
, 2005
"... Summary 1. Increasingly, river managers are turning from hard engineering solutions to ecologically based restoration activities in order to improve degraded waterways. River restoration projects aim to maintain or increase ecosystem goods and services while protecting downstream and coastal ecosys ..."
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Cited by 77 (5 self)
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Summary 1. Increasingly, river managers are turning from hard engineering solutions to ecologically based restoration activities in order to improve degraded waterways. River restoration projects aim to maintain or increase ecosystem goods and services while protecting downstream and coastal ecosystems. There is growing interest in applying river restoration techniques to solve environmental problems, yet little agreement exists on what constitutes a successful river restoration effort. 2. We propose five criteria for measuring success, with emphasis on an ecological perspective. First, the design of an ecological river restoration project should be based on a specified guiding image of a more dynamic, healthy river that could exist at the site. Secondly, the river's ecological condition must be measurably improved. Thirdly, the river system must be more self-sustaining and resilient to external perturbations so that only minimal follow-up maintenance is needed. Fourthly, during the construction phase, no lasting harm should be inflicted on the ecosystem. Fifthly, both pre-and postassessment must be completed and data made publicly available. 3. Determining if these five criteria have been met for a particular project requires development of an assessment protocol. We suggest standards of evaluation for each of the five criteria and provide examples of suitable indicators. 4. Synthesis and applications . Billions of dollars are currently spent restoring streams and rivers, yet to date there are no agreed upon standards for what constitutes ecologically beneficial stream and river restoration. We propose five criteria that must be met for a river restoration project to be considered ecologically successful. It is critical that the broad restoration community, including funding agencies, practitioners and citizen restoration groups, adopt criteria for defining and assessing ecological success in restoration. Standards are needed because progress in the science and practice of river restoration has been hampered by the lack of agreed upon criteria for judging ecological success. Without well-accepted criteria that are ultimately supported by funding and implementing agencies, there is little incentive for practitioners to assess and report restoration outcomes. Improving methods and weighing the ecological benefits of various restoration approaches require organized national-level reporting systems.
Ecological theory and community restoration ecology. Restoration Ecology 5:291–300.
, 1997
"... Abstract Community ecological theory may play an important role in the development of a science of restoration ecology. Not only will the practice of restoration benefit from an increased focus on theory, but basic research in community ecology will also benefit. We pose several major thematic ques ..."
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Cited by 55 (3 self)
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Abstract Community ecological theory may play an important role in the development of a science of restoration ecology. Not only will the practice of restoration benefit from an increased focus on theory, but basic research in community ecology will also benefit. We pose several major thematic questions that are relevant to restoration from the perspective of community ecological theory and, for each, identify specific areas that are in critical need of further research to advance the science of restoration ecology. We ask, what are appropriate restoration endpoints from a community ecology perspective? The problem of measuring restoration at the community level, particularly given the high amount of variability inherent in most natural communities, is not easy, and may require a focus on restoration of community function (e.g., trophic structure) rather than a focus on the restoration of particular species. We ask, what are the benefits and limitations of using species composition or biodiversity measures as endpoints in restoration ecology? Since reestablishing all native species may rarely be possible, research is needed on the relationship between species richness and community stability of restored sites and on functional redundancy among species in regional colonist "pools." Efforts targeted at restoring system function must take into account the role of individual species, particularly if some species play a disproportionate role in processing material or are strong interactors. We ask, is restoration of habitat a sufficient approach to reestablish species and function? Many untested assumptions concerning the relationship between physical habitat structure and restoration ecology are being made in practical restoration efforts. We need rigorous testing of these assumptions, particularly to determine how generally they apply to different taxa and habitats. We ask, to what extent can empirical and theoretical work on community succession and dispersal contribute to restoration ecology? We distinguish systems in which succession theory may be broadly applicable from those in which it is probably not. If community development is highly predictable, it may be feasible to manipulate natural succession processes to accelerate restoration. We close by stressing that the science of restoration ecology is so intertwined with basic ecological theory that practical restoration efforts should rely heavily on what is known from theoretical and empirical research on how communities develop and are structured over time.
Basic principles and ecological consequences of changing water regimes: riparian plant communities
- North Carolina Administrative Code. 2013. 15A NCAC 2B.. http://portal.ncdenr.org/web/wq/ps/csu/swstandards. North Carolina Administrative Code. Inter Basin Transfers. Article 1 of Chapter 113A of the General Statutes. & G.S
, 2002
"... ABSTRACT / Recent research has emphasized the importance of riparian ecosystems as centers of biodiversity and links between terrestrial and aquatic systems. Riparian ecosystems also belong among the environments that are most disturbed by humans and are in need of restoration to maintain biodivers ..."
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Cited by 28 (0 self)
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ABSTRACT / Recent research has emphasized the importance of riparian ecosystems as centers of biodiversity and links between terrestrial and aquatic systems. Riparian ecosystems also belong among the environments that are most disturbed by humans and are in need of restoration to maintain biodiversity and ecological integrity. To facilitate the completion of this task, researchers have an important function to communicate their knowledge to policy-makers and managers. This article presents some fundamental qualities of riparian systems, articulated as three basic principles. The basic principles proposed are: (1) The flow regime determines the successional evolution of riparian plant communities and ecological processes. (2) The riparian corridor serves as a pathway for redistribution of organic and inorganic material that influences plant communities along rivers. (3) The riparian system is a transition zone between land and water ecosystems and is disproportionately plant species-rich when compared to surrounding ecosystems. Translating these principles into management directives requires more information about how much water a river needs and when and how, i.e., flow variables described by magnitude, frequency, timing, duration, and rate of change. It also requires information about how various groups of organisms are affected by habitat fragmentation, especially in terms of their dispersal. Finally, it requires information about how effects of hydrologic alterations vary between different types of riparian systems and with the location within the watershed.
Large woody debris in urban streams of the Pacific Northwest
- Effects of watershed development and management on aquatic ecosystems: Engineering Foundation Conference, Proceedings, Snowbird, UT
, 1997
"... Large woody debris (LWD) performs key functions in undisturbed streams that drain lowland forested watersheds, including dissipation of flow energy, stabilization of bedforms and channel banks, entrapment of sediment, and formation of pools. These functions vary between individual channels, however, ..."
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Cited by 14 (4 self)
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Large woody debris (LWD) performs key functions in undisturbed streams that drain lowland forested watersheds, including dissipation of flow energy, stabilization of bedforms and channel banks, entrapment of sediment, and formation of pools. These functions vary between individual channels, however, depending on the size and morphology of the stream, which in turn depend on climate, watershed size, valley slope, geologic substrate, and relative inputs of water and sediment. Loss of LWD will alter channel form and processes, yielding greater sediment fluxes, more rapid bank erosion and incision, and loss of heterogeneity in bed morphology. Just as LWD is ubiquitous in undisturbed lowland streams of the Pacific Northwest, it is significantly depleted in urbanized systems where it is lost through washout, downcutting, and direct removal. Given the dramatic changes in runoff processes and sediment delivery that typify urban watersheds, we doubt that simple reintroduction of LWD will fully restore the lost functions of urban streams. Instead, projects that replace LWD may be best suited to recover a more limited set
Monitoring urban streams: Strategies and protocols for humid-region lowland systems. Environmental Monitoring and Assessment
, 2001
"... Abstract. Governmental mandates and public awareness have forced progressively smaller and less sophisticated agencies and organizations to initiate stream monitoring programs, particularly in urban and urbanizing areas. Yet many of these monitoring efforts lack either a coherent conceptual framewor ..."
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Cited by 7 (0 self)
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Abstract. Governmental mandates and public awareness have forced progressively smaller and less sophisticated agencies and organizations to initiate stream monitoring programs, particularly in urban and urbanizing areas. Yet many of these monitoring efforts lack either a coherent conceptual framework or appropriately chosen methods, and they rely on monitoring techniques that are simply infeasible for these institutional settings. We propose a monitoring strategy, and specific existing monitoring protocols, that will be useful for the management and rehabilitation of streams in ur-banizing watersheds. A monitoring strategy must be developed by 1) identifying the management question(s) being addressed, 2) determining the institional level of effort required (and available) to effectively make particular kinds of measurements, and 3) identifying what specific parameters should and can be measured. Only a limited set of parameters show much utility or feasibility in addressing the most common management questions being faced by municipalities in urbanizing, humid-area regions of the United States. These include measures of riparian canopy, bank erosion and bank hardening, and in-stream large woody debris. With some additional expertise useful data can also be included on channel gradient, substrate composition, and pools. Nearly all of the other myriad parameters that have been measured historically on rivers and streams show little apparent value in these watershed and institutional settings.
Interpolation of Fluvial Morphology Using Channel-Oriented Coordinate Transformation: A Case Study From the New Jersey Shelf 1
"... We present a new methodology for interpolating channel morphology that incorporates a transformation from geographic to channel-based coordinate systems. Interpolation in the transformed space enables enforcement of downstream continuity of morphology and edge delineation through any changes in chan ..."
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Cited by 6 (1 self)
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We present a new methodology for interpolating channel morphology that incorporates a transformation from geographic to channel-based coordinate systems. Interpolation in the transformed space enables enforcement of downstream continuity of morphology and edge delineation through any changes in channel direction. The transformation is guided by a “channel center line, ” which approximately tracks the path of the channel through geographic space; coordinates are given in distance along and across the center line. Accurate interpolation requires a track line density sufficient to unambiguously trace channels from one track line to the next. Channel continuity is ensured by first interpolating along paths defined by the channel thalweg and edges, which must be chosen by the user, and along several interim paths between the edges and thalweg. The completed interpolations for each channel are transformed back into geographic coordinates, and channel confluence is handled through a maximum depth criterion. The method is applied here to shallowly buried channels mapped with high-resolution chirp seismic data on the New Jersey shelf, but should be applicable to a wide range of subaerial and buried fluvial systems. KEY WORDS: chirp seismic data, acoustic modeling, geomorphic parameters, paleoenvironment.
tilings, in preparation
- Department of Mathematics, Harvard University, Cambridge
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Evaluation of Sediment Transport Data For Clean Sediment TMDLs
, 2000
"... Excessive erosion, transport, and deposition of sediment in surface waters is a major problem in the United States. A national strategy is needed to develop scientifically defensible procedures to facilitate the development of TMDL’s for clean sediment in streams and rivers of the United States. In ..."
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Cited by 5 (2 self)
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Excessive erosion, transport, and deposition of sediment in surface waters is a major problem in the United States. A national strategy is needed to develop scientifically defensible procedures to facilitate the development of TMDL’s for clean sediment in streams and rivers of the United States. In the first part of this study data sets which contain sediment transport and flow data were identified from non-USGS sites. In the second part of this study, an existing method for evaluating impairment of streams by sediment (Rosgen-Troendle technique) was evaluated, problems were identified and a revised technique was developed. This revised technique will be useful in the identification of problems, water quality indicators, and target values for clean sediment TMDLs in streams and rivers (USEPA, 1999). A search of existing data sets yielded 108 sites in the United States with detailed sediment and flow data suitable for testing of procedures for the development of clean sediment TMDLs. The data from these streams was from 11 different states and nine different physiographic provinces of the country and would serve as a valuable resource for further development of procedures to detect impairment due to clean sediment. The Rosgen-Troendle technique (Troendle, 2000, written communication) assumes clean
