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United StatesDepartment ofAgricultureForest ServicePacific NorthwestResearch StationGeneral TechnicalReportPNW-GTR-692February 2007Riparian and Aquatic Habitats of thePacific Northwest and SoutheastAlaska: Ecology, ManagementHistory, and Potential ManagementStrategiesFred H. Everest and Gordon H. Reeves

The Forest Service of the U.S. Department of Agriculture is dedicated to theprinciple of multiple use management of the Nation’s forest resources for sustained yields of wood, water, forage, wildlife, and recreation. Through forestryresearch, cooperation with the States and private forest owners, and management of the national forests and national grasslands, it strives—as directed byCongress—to provide increasingly greater service to a growing Nation.The U.S. Department of Agriculture (USDA) prohibits discrimination in all itsprograms and activities on the basis of race, color, national origin, age, disability,and where applicable, sex, marital status, familial status, parental status, religion,sexual orientation, genetic information, political beliefs, reprisal, or because all orpart of an individual’s income is derived from any public assistance program. (Notall prohibited bases apply to all programs.) Persons with disabilities who requirealternative means for communication of program information (Braille, large print,audiotape, etc.) should contact USDA’s TARGET Center at (202) 720-2600 (voiceand TDD).To file a complaint of discrimination write USDA, Director, Office of Civil Rights,1400 Independence Avenue, S.W. Washington, DC 20250-9410, or call (800) 7953272 (voice) or (202) 720-6382 (TDD). USDA is an equal opportunity provider andemployer.AuthorsFred H. Everest is an associate professor of environmental technology (retired),University of Alaska Southeast, Sitka Campus, 1332 Seward Avenue, Sitka, AK99835; and Gordon H. Reeves is a research fishery biologist, U.S. Department ofAgriculture, Forest Service, Pacific Northwest Research Station, Forestry SciencesLaboratory, 3200 SW Jefferson Way, Corvallis, OR 97331. Everest is currentlylocated at P.O. Box 1444, Sitka, AK 99835.

AbstractEverest, Fred H.; Reeves, Gordon H. 2006. Riparian and aquatic habitats of thePacific Northwest and southeast Alaska: ecology, management history, andpotential management strategies. Gen. Tech. Rep. PNW-GTR-692. Portland,OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station. 130 p.Management of riparian habitats is controversial because land use policies havehistorically emphasized economic values (e.g., timber production) at the expenseof ecological and social values. Attempting to manage these valuable resources toattain the greatest combination of benefits has created a long-term controversy thatcontinues to the present. Our analysis indicates that at mid to large spatial scales,healthy riparian ecosystems and land management activities are not mutuallyexclusive, but the degree of compatibility is determined by policy decisions basedon competing demands and pressing timelines as well as available scientific knowledge. Current management schemes on federal lands in the Pacific Northwest andAlaska are appropriately addressing large spatial scales and incorporating theprinciples of disturbance ecology. We found no scientific evidence that either thedefault prescriptions or the options for watershed analysis in the Northwest ForestPlan and Tongass Land Management Plan provide more protection than necessaryto meet stated riparian management goals. We believe that additional alternativeriparian management strategies could be implemented and evaluated in concert toshorten the time needed to realize effective strategies that fully meet riparianmanagement goals.Keywords: Riparian ecosystems, management, dynamics, Northwest ForestPlan, Tongass Land Management Plan.i

PrefaceManagement of riparian habitats, especially on forest lands west of the Cascadecrest in Oregon and Washington, and in southeast Alaska, has been a subject ofcontroversy for decades. Why the controversy? Riparian zones produce and maintain many resources of economic, ecological, and social value. Often the mostvaluable timber in watersheds, e.g., Port Orford cedar in the Pacific Northwestand Sitka spruce and red and yellow-cedar in southeast Alaska, grows in moist sites12provided by riparian zones. In addition, science has demonstrated that riparianhabitat in western Oregon and Washington, southeast Alaska, and other locationssupports higher densities and diversities of flora and fauna than other portions of345the landscape. The natural functions of riparian ecosystems are important contributors to the maintenance of watershed hydrology, streamflows, water quality,stream nutrients, and habitat characteristics needed to maintain the viability of6native aquatic species, including many economically significant species. Riparian1Franklin, J.F.; Dyrness, C.T. 1973. Natural vegetation of Oregon and Washington. Gen.Tech. Rep. PNW-8. Portland, OR: U.S. Department of Agriculture, Forest Service, PacificNorthwest Research Station. 417 p.2U.S. Department of Agriculture, Forest Service [USDA Forest Service]. 1997. Tongassland management plan revision. Final environmental impact statement Part 1: summary,chapters 1 and 2, and chapter 3 (physical and biological environment). R10-MB-338b.Washington, DC. [Irregular pagination].3Crow, T.R.; Baker, M.E.; Barnes, B.V. 2000. Diversity in riparian landscapes. In: Verry,E.S.; Hornbeck, J.W.; Dolloff, C.A., eds. Riparian management in forests of thecontinental Eastern United States. New York: Lewis Publishers: 43-66.4Oakley, A.L.; Collins, J.A.; Everson, L.B. [et al.]. 1985. Riparian zones and freshwaterwetlands. In: Brown, E.R., ed. Management of wildlife and fish habitats in forests ofwestern Oregon and Washington. Part 1–Chapter narratives. Portland, OR: U.S.Department of Agriculture, Forest Service, Pacific Northwest Region: 57-80.5Olson, D.H.; Chan, S.S.; Weaver, G. [et al.]. 2000. Characterizing stream, riparian, andupslope habitats and species in Oregon managed headwater forests. In: Wiggington, J.;Beschta, R., eds. Riparian ecology and management in multi-land use watersheds. AWRAPublication TPS-00-2. International conference of the American Water ResourcesAssociation. Middleburg, VA: American Water Resources Association: 83-88.6Naiman, R.J.; Beechie, T.J.; Benda, L.E. [et al.]. 1992. Fundamental elements ofecologically healthy watersheds in the Pacific Northwest coastal region. In: Naiman, R.J.,ed. Watershed management: balancing sustainability and environmental change. Seattle,WA: University of Washington, Center for Streamside Studies: 127-188.ii

zones are focal areas for recreation and have high aesthetic appeal for many out7 8door activities. Other social and economic benefits of riparian zones accrue tofishers, hunters, farmers, loggers, resort owners, municipalities, miners, and9others. Unfortunately, not all benefits of riparian areas can be realized simultaneously at all times, because some are mutually exclusive at small spatial scales.However, it is possible to manage riparian ecosystems to achieve a combinationof benefits at larger spatial scales, e.g., the large watershed scale. The uses ofriparian ecosystems, and the question of how to achieve a socially acceptablebalance among economic, ecological, and social uses, lies at the heart of theriparian debate.Alteration of riparian habitats has been implicated as a contributor in thedecline of freshwater habitat for anadromous salmonids in the Pacific Northwest.Several stocks of anadromous salmonids in the region were listed as threatened orendangered in the 1990s, and attempts to recover those populations currentlyaddress concerns with freshwater habitat, fish harvest, hydropower development,and fish hatcheries. Recovery efforts include development of new riparian management strategies that provide more protection for riparian and aquatic habitats onforest lands than previous management schemes. The new strategies have intensifiedthe ongoing debate surrounding the appropriate goals and practices for managementand protection of riparian habitats.The controversy surrounding management of riparian areas extends to all landuses, including agriculture, urban landscapes, water development projects, forestry,and others, and to all land ownerships. However, in the Pacific Northwest andsoutheast Alaska, the controversy currently focuses largely on riparian managementin forested watersheds. Expansion of that focus to include whole river basins andother land uses and ownerships, however, could provide a more holistic and perhapsmore viable approach to management of riparian ecosystems, land managementactivities as a whole, and recovery of threatened and endangered species.7Schroeder, H.W. 1996. Voices from Michigan’s Black River: obtaining information on“special places” for natural resource planning. Gen. Tech. Rep. NC-184. St. Paul, MN:U.S. Department of Agriculture, Forest Service, North Central Forest Experiment Station.26 p.8Stynes, D.J. 1997. Recreation activity and tourism spending in the Lake States. In:Webster, H.H.; Vasievich, J.M., eds. Lake States regional forest resources assessment:technical papers. Gen. Tech. Rep. NC-189. St. Paul, MN: U.S. Department of Agriculture,Forest Service, North Central Forest Experiment Station: 139-164.9Dwyer, J.F.; Jakes, P.J.; Barro, S.C. 2000. The human dimensions of riparian areas:implications for management and planning. In: Verry, E.S.; Hornbeck, J.W.; Dolloff, C.A.,eds. Riparian management in forests of the continental Eastern United States. New York:Lewis Publishers: 193-206.iii

An examination of land ownership, land cover, and land uses in the Northwestand southeast Alaska provides perspective on the comparative importance of riparianlands managed by private and public landowners. Approximately 52 percent of theland base in the Northwest is privately owned forest land, rangeland, cropland,10pasture, and urban and residential properties. Most of the privately owned landscape consists of lowlands and valleys in downstream areas of the region’s majorriver basins, where riparian and aquatic ecosystems historically provided important11 12 13 14habitats for production of fish and other aquatic resources.Dams, reservoirs,irrigation systems, cultivation, use of pesticides and fertilizers, urbanization, andtransportation systems have altered many riparian and aquatic habitats in these areas,with perhaps the greatest effects associated with agriculture and hydropower pro15 16 17duction.Because of intensive land use on large expanses of private land, and10Pease, J. 1993. Land use and ownership. In: Jackson, P.; Kimerling, A., eds. Atlas of thePacific Northwest. 8th ed. Corvallis, OR: Oregon State University Press: 31-39.11Brown, T.G.; Hartman, G.F. 1988. Contribution of seasonally flooded lands and minortributaries to the production of coho salmon in Carnation Creek, British Columbia.Transactions of the American Fisheries Society. 117: 546-551.12Li, H.; Schreck, C.B.; Bond, C.E.; Rexstad, E. 1987. Factors influencing changes in fishassemblages in Pacific Northwest streams. In: Matthews, W.J.; Heins, D.C., eds.Community and evolutionary ecology of North American stream fishes. Norman, OK:University of Oklahoma Press: 193-202.13Peterson, N.P.; Reid, L.M. 1984. Wall based channels: their evolution, distribution, anduse by juvenile coho salmon in the Clearwater River, Washington. In: Walton, J.M.;Houston, D.B., eds. Proceedings of the Olympic Wild Fish Conference. Port Angeles,WA: Fisheries Technology Program, Peninsula College: 215-226.14Sedell, J.R.; Reeves, G.H.; Hauer, F.P. [et al.]. 1990. Role of refugia in recovery fromdisturbance: modern fragmented and disconnected river systems. EnvironmentalManagement. 14: 711-724.15Beechie, T.; Beamer, E.; Wasserman, L. 1994. Estimating coho salmon rearing habitatand smolt production losses in a large river basin, and implications for restoration. NorthAmerican Journal of Fisheries Management. 14: 797-811.16Bradford, J.M.; Irvine, J.R. 2000. Land use, fishing, climate change, and the decline ofThompson River, British Columbia, coho salmon. Canadian Journal of Fisheries andAquatic Sciences. 57: 13-16.17Everest, F.H.; Kakoyannis, C.; Houston, L. [et al.]. 2004. A synthesis of scientificinformation on emerging issues related to use and management of water resources onforested landscapes of the Pacific Northwest. Gen. Tech. Rep. PNW-GTR-595. Portland,OR: U.S. Department of Agriculture, Forest Service, Pacific Northwest Research Station.128 p.iv

dams whose effective lifespans may be measured in centuries, return to the historical character of riparian and aquatic habitats is unlikely on much of this land18scape. Many of the changes in riparian and aquatic ecosystems resulting fromagriculture and hydropower development can probably be considered irreversible,at least in the near term.In contrast to the widespread and persistent alteration of riparian and aquatichabitats on nonforest lands, management of public forest lands generally has madefewer and less persistent changes in riparian and aquatic ecosystems. The most extensive habitat changes west of the Cascade crest in Oregon and Washington andin southeast Alaska are associated with timber harvest, but those effects, with theexception of roads, are potentially temporary and reversible.The federal government manages nearly 48 percent of the land base in thePacific Northwest. National forests managed by the U.S. Forest Service and rangelands managed by the Bureau of Land Management, national parks, and nationalwildlife refuges, account for a large percentage of Oregon (48.2 percent) andWashington (29.8 percent) (table 1). Federal lands west of the Cascade crest inOregon and Washington total about 4.6 million ha, of which about 4.1 million ha isforested. About 59 percent of the forested landscape has been managed for production of timber and other resources. The remainder is in wilderness, or areas administratively withdrawn from forest management. Federal holdings consist largely offorests and rangelands that are generally in the higher elevation mountains of theregion. Many of these areas produce large amounts of water and contain some of the19best remaining habitats for native aquatic organisms (see footnote 17). These landscontain numerous small streams and associated riparian ecosystems that, in combination, are largely responsible for the quantity and quality of water and aquatichabitats within the forested landscape.More than 62 percent of Alaska is owned and managed by the federal government (table 1), but to date, management activities have resulted in limited modification of riparian and aquatic habitats on these lands. In the sparsely populated18Gregory, S.V.; Bisson, P.A. 1997. Degradation and loss of anadromous salmonidhabitat in the Pacific Northwest. In: Stouder, D.J.; Bisson, P.A.; Naiman, R.J., eds. Pacificsalmon and their ecosystems. New York: Chapman and Hall: 277-314.19Sedell, J.; Sharpe, M.; Dravneiks, D. [et al.]. 2000. Water and the Forest Service. FS660. Washington, DC: U.S. Department of Agriculture, Forest Service. 26 p.v

Table 1—Land ownership and land use in the Pacific Northwest and AlaskaLand 37,04024,6807,7503,8106800%301921151032 22941322344Total federalTotal nonfederal129,520121,260524852,430123,737Total ngelandCroplandPastureUrbanNational ,44029,310%211421302,411380195,460728,355 1 1 113493070922,670554,60062381001,477,270100Sources: Pacific Northwest, Pease 1993; Alaska, Alaska DNR 2000, US GSA 2000, NPS 2005, PublicLand Statistics 2000, USDA Forest Service 2000.temperate rain forests of southeast Alaska, the federal government owns about 95percent of the landscape: about 80 percent of federal rain forest in Alaska is in theTongass National Forest and most of the remainder is in Glacier Bay National Park(see footnote 2). About 2.2 million ha of productive old-growth forest exists in theTongass National Forest; about 1.7 million ha is designated wilderness or administratively withdrawn from forest management, and about 162 000 ha was harvestedthduring the last half of the 20 century. Most streams, riparian habitats, and water20sheds in the region remain largely unaffected by human activities.The conclusion to be drawn from the overview of land ownership and land use,especially in the Pacific Northwest, is that many low-elevation aquatic and riparianhabitats in major river basins, mostly on private lands, have been converted fromlowland and flood-plain forests to nonforested agricultural lands, reservoirs, andurban lands (see footnote 14). Riparian and aquatic ecosystems on these landshistorically provided important habitats for many aquatic species. These habitats,prior to alteration, may have been the most important rearing areas for specificlife-history stages of some anadromous salmonids at certain seasons of the year (see20Bryant, M.D.; Everest, F.H. 1997. Management and condition of watersheds insoutheast Alaska: the persistence of anadromous salmon. Northwest Science. 72(4):249-267.vi

footnotes 11, 12, and 13). Many of these habitats no longer support historicalindigenous aquatic communities.Some riparian and aquatic habitats on forest lands under federal managementhave also been altered, but to a lesser extent than on privately owned lands. Thesehabitats were also important historical producers of anadromous salmonids andother aquatic species and still contain some of the best remaining aquatic habitats inthe region. Recovery of riparian and aquatic habitats on both forest lands andnonforest lands in western Oregon and Washington is currently being addressed byfederal and state agencies and nongovernmental organizations.Current and previous state and federal goals for riparian management aresimilar in that they all aim to protect water quality as well as riparian and aquatichabitats. However, policymakers have developed different strategies for achievingthe goals state to state and by land ownership, fueling the debate about how toachieve management goals. Some questions in the riparian management debate aredecades old and still unanswered. For example: Are land management activities and healthy aquatic and riparian ecosystemsmutually exclusive? If not, how much and what type of land management can be conductedwithout undesirable social, economic, or ecological effects on riparianecosystems?Other questions are of more recent origin, for example: Are current riparian management schemes addressing the appropriate spatial and temporal scales?Have the riparian management schemes recently applied on federal landsgone too far in protecting ecological values at the expense of some socialand economic values? Are there new or emerging options for managing riparian ecosystems thatwill improve multiple resource use at the watershed scale yet still maintaindesired characteristics of riparian and aquatic resources?We will explore these questions in this paper.vii

Executive SummaryRiparian habitats on forest lands west of the Cascade crest in Oregon and Washington and in southeast Alaska produce a variety of ecological, economic, and socialvalues. Management of riparian habitats, however, is controversial because land usepolicies have historically favored some of these values (e.g., timber production) atthe expense of others. The attempt to manage these valuable resources to attain thegreatest combination of benefits has created a long-term controversy that continuesto the present.Some of the questions in the debate are decades old and still unanswered. Forexample, are land management activities and healthy aquatic and riparian ecosystems mutually exclusive? If not, how much and what type of land management canbe conducted without undesirable social, economic, or ecologic effects on riparianecosystems? Other questions are of more recent origin; for example, are currentriparian management schemes addressing the appropriate spatial and temporalscales? Have the riparian management schemes recently applied on federal landsgone too far in protecting ecological values at the expense of some social andeconomic values? Are there new or emerging options for managing riparian ecosystems that will improve multiple resource use at the watershed scale, yet still maintain desired characteristics of riparian and aquatic resources? We attempt to answerthese questions in this paper.Our objectives focus on (1) how riparian areas can be defined and delineated;(2) a brief examination of the structure, function, and benefits of riparian ecosystems; (3) a review of the role that natural and human disturbances play in the function of riparian and aquatic ecosystems in forests of the Pacific Northwest andsoutheast Alaska; (4) a review of the development of forest practice rules in thePacific Northwest and southeast Alaska; and (5) an examination of potential riparianmanagement strategies that might increase compatibility among the different valuessought from forest lands.Riparian zones can be defined by either their physical or functional attributes,but recent definitions tend to emphasize function and, therefore, from a management perspective, increase the geographic extent of riparian ecosystems.The structural features of riparian ecosystems are highly variable, but allshare common physical elements that are controlled by environmental phenomena.Physical characteristics of riparian habitats are defined in time and space by climaticconditions, vegetation types, stream order, and geomorphic features like channelviii

gradient, elevation, slope, aspect, and perhaps other factors. When defined physically, riparian ecosystems generally have a linear structure that may be hundreds ofkilometers in length and highly variable in width. The flood plains of large rivers,for example, may contain extensive riparian habitats with widths of a kilometer ormore. Conversely, riparian zones along small, incised headwater streams may beonly a few meters wide.When viewed functionally, riparian ecosystems provide a variety of importantlinkages and ecological functions for adjacent aquatic and upland ecosystems. Keyfunctions include the maintenance of water quality, control of sediment deliveryfrom uplands and sediment movement in streams, control of the movement ofnutrients and contaminants, control of streambed and bank stability, and the maintenance of fish and wildlife habitats in adjacent ecosystems.Benefits provided by riparian zones are strongly related to their structure andfunction. Although it is possible to think of the benefits in ecological, social, oreconomic terms, in most cases, the benefits blend across the three categories. Someof the benefits are strongly associated with unmanaged riparian habitats, whereasothers may be derived from active riparian management. Some major benefits thataccrue to society from riparian ecosystems include maintenance of water qualityin streams, lakes, shallow groundwater strata, and hyporheic zones; maintenanceof stream channel stability and hydrologic function in watersheds; contribution tomaintenance of biodiversity in watersheds and the maintenance of viable populations of riparian, aquatic, and terrestrial species; focal sites for outdoor recreation;enhancement of the value of private residential and commercial properties; contribution to visual aesthetics in managed landscapes; maintenance of aesthetics in wildand scenic river corridors; flood control; maintenance of streamflows for humanuses; high-quality potable water for domestic and industrial use; production of highvalue aquatic resources (e.g., anadromous salmonids); timber production; livestockproduction from grazing on riparian forage; and mining for gold and other minerals. The variety of ecological, social, and economic benefits provided by riparianzones contribute to the controversy surrounding their management in Westernwatersheds.Watersheds throughout the Pacific Northwest and southeast Alaska are subjectto disturbances from natural events such as fire, floods, and wind and human activities such as construction of dams and reservoirs, agriculture, and timber harvest.ix

The type and timing of disturbances largely determine their effects on ecosystemresilience, ecological processes, and indigenous biota. Ecosystem disturbances canbe classified as either “pulse” or “press” disturbances based on their temporal andspatial frequency. Pulse disturbances (e.g., wildfire) occur infrequently, and allowsufficient time between disturbances to enable ecosystems to recover to predisturbance conditions. Pulse disturbances generally allow ecosystems to remain withintheir normal historical range of states and conditions. Press disturbances (e.g., timber harvest), on the other hand, are characterized by frequent or continual eventsinterspersed with insufficient recovery time to allow ecosystems to return topredisturbance conditions. Press disturbances generally reduce the resiliency ofecosystems, and may ultimately impose new regimes of variability that are outsideof the natural historical range of a watershed or ecoregion. Natural and humandisturbance regimes can fall into either the pulse or press category, although naturaldisturbances are most often associated with the former and human disturbances withthe latter.States and federal agencies have developed rules and practices to protect riparian zones from forest management. Those practices evolved over a period of morethan 30 years to accommodate new scientific information and provide increasedriparian protection. The culmination of forest practice rules resulted in development of the Northwest Forest Plan (NWFP) and the Tongass Land ManagementPlan (TLMP) for protection of riparian zones on federal lands and revised stateforest practices acts for protection on state and private lands in the region. Currentstate-of-the-art forest practices provide extensive protection to riparian ecosystems,but they have not been fully evaluated, so their efficacy remains unknown.In regard to the original questions we posed, first our analysis indicates that atmid to large spatial scales, healthy riparian ecosystems and land management activities are not mutually exclusive, but the degree of success in achieving compatibilityis determined by policy decisions based on competing demands and pressing timelines as well as available scientific knowledge. Second, we found that current management schemes are appropriately addressing large spatial scales and incorporatingthe principles of disturbance ecology. Third, we found no scientific evidence thateither the default prescriptions or the options for watershed analysis in the NWFPand TLMP provide more protection than necessary to meet stated riparian management goals. Finally, we found that additional alternative riparian managementx

strategies could be implemented and evaluated in concert to shorten the time neededto realize effective strategies that fully meet riparian management goals. Emergingand future strategies for riparian management that are science-based, considernatural processes, and address large temporal and spatial scales in an interagencyforum that includes all concerned stakeholders appear to hold promise for thefuture. Precedent has been set, for example, in organizations like the DeschutesRiver Basin Conservancy and the Coastal Landscape Analysis and Modeling Studyin Oregon. In reality, however, the direction of riparian management will be determined, not by science, but by the normative decisions of policymakers who attemptto achieve a balance between ecosystem sustainability and the competing demandsof resource users.xi

999xiiIntroductionGeographic ScopeObjectivesDefinition of Riparian Ecosystems and Delineation of Riparian ZonesStructure, Function, and Benefits of Riparian ZonesStructureFunctionBenefitsEffects of Watershed Disturbances on Riparian Structure and FunctionNatural DisturbancesSummary of Natural DisturbancesHuman DisturbancesSummary of Human DisturbancesEvolution of Riparian Management in Oregon, Washington, andSoutheast AlaskaEstablishment and Evolution of Forest Practice RulesCommonalities in Development of Forest Practice RulesBenefits and Costs of Forest Practice Rules DevelopmentPotential Options for Riparian Management StrategiesTemporal and Spatial ConsiderationsFocus on Forested LandsConsiderations for Future Riparian Management on Forest LandsCriteria for Next StepsExamples of Potential Riparian Management StrategiesConclusionsEnglish EquivalentsLiterature Cited

Riparian and Aquatic Habitats of the Pacific Northwest and Southeast AlaskaIntroductionRiparian ecosystems are important components of watersheds worldwide, and muchof what is known about their structure and function has universal application. In thehumid mountain ecosystems of the Pacific Northwest United States (PNW), southeast Alaska, and elsewhere, riparian areas are used by a rich and diverse assemblageof species (Odum 1979) and provide critical transition zones linking terrestrialand aquatic ecosystems within watersheds (Naiman et al. 1992, 2002; Oliver andHinckley 1987). Riparian ecosystems, from a functional standpoint, also exertimportant controls over the characteristics of rivers and streams. Healthy riparianecosystems contribute to natural temporal and spatial regimens of streamflow,Riparian ecosystemsexert importantcontrols over thecharacteristics ofrivers and streams.water quality (U.S. Army Corps of Engineers 1991), nutrient supply (Clinton et al.2002, Nakano et al. 1999), and the physical structur

Fred H. Everest is an associate professor of environmental technology (retired), . (e.g., timber production) at the expense of ecological and social values. Attempting to manage these valuable resources to attain the greatest combination of benefits has created a long-term controversy that . Final