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1.
John H. Schomaker 《Journal of the American Water Resources Association》1983,19(3):463-467
For a risk recreation activity like whitewater boating, a manager's goal of providing for the health and safety of the visitor may conflict with the goal of providing the opportunity for a satisfying recreation experience. As whitewater river managers face the problem of safety and risks, they should consider what users think about safety programs. The views of whitewater boaters toward (1) first aid equipment requirements, (2) signs warning of hazards, (3) aggressive enforcement of the rules, and (4) patrols to assist and regulate users were determined on 13 river segments in the western United States. A test was made of the relation between views toward safety measures and the level of risk and thrills sought by floaters. Conclusions of the study are: (1) river floaters' views toward possible management safety measures are not related to the amount of risk they desire; and (2) floaters, in general, prefer some safety measures to others. If safety measures mean that managers will be more visible on the river, floaters tend to dislike them. Therefore, a manager's approach to safety management should parallel the approach to recreation management in general, and regulation of use should be the minimum necessary to achieve safety objectives. 相似文献
2.
A practical scientific approach to riparian vegetation rehabilitation in Australia 总被引:20,自引:0,他引:20
The clearance of indigenous riparian vegetation and removal of large woody debris (LWD) from streams combined with the planting of exotic plant species has resulted in widespread detrimental impacts on the fluvial geomorphology and aquatic ecology of Australian rivers. Vegetation exerts a significant influence on fluvial geomorphology by affecting resistance to flow, bank strength, sediment storage, bed stability and stream morphology and is important for aquatic ecosystem function. As the values of indigenous riparian vegetation are becoming better recognised by Australian river managers, large amounts of money and resources are being invested in the planting of indigenous riparian vegetation as part of river rehabilitation programs. This paper summarises the results of an investigation into the survival, growth and regeneration rates of a series of trial native riparian vegetation plantings on in-channel benches in the Hunter Valley of southeastern Australia. The trials were poorly designed for statistical analysis and the paper highlights a number of shortcomings in the methods used. As a result, a new approach to riparian vegetation rehabilitation is outlined that promotes the use of scientific principles and understanding. Appropriate species should be selected using a combination of remnant vegetation surveys, historical records, palynology and field trials. A number of important factors should be considered in the rehabilitation of riparian vegetation to achieve worthwhile results. These include flood disturbance, vegetation zonation, vegetation succession, substrate composition, corridor planting width, planting techniques, native plant regeneration, LWD recruitment and adaptive ecosystem management. This approach, if adopted, revised and improved by river managers, should result in greater success than has been achieved by previous riparian vegetation rehabilitation efforts in Australia. 相似文献
3.
Stephen F. McCool Jack Utter 《Journal of the American Water Resources Association》1981,17(3):431-437
Allocating river recreation use to commercial and private sectors on white water rivers has been highly controversial. How this process is implemented may affect not only the availability of recreation opportunities to individual users, but may also negatively impact the user's desire to escape from the pressures and stresses of everyday life. In a study of users of Idaho's Middle Fork of the Salmon River, an Even-Pool allotment technique was preferred over others by the commercial, private, and rejectee individuals sampled. A lottery technique for rationing private use permits was preferred by private users and rejectees, while commercial users preferred Advance Reservation. No relationship was found between the users' stress release/escape expectations and their preferences for the different allotment and rationing techniques studies. Such results suggest that river managers may have considerable latitude in selecting allocation techniques that do not adversely affect on-site recreation experiences. 相似文献
4.
Peter J. Hancock 《Environmental management》2001,29(6):763-781
Active exchanges of water and dissolved material between the stream and groundwater in many porous sand- and gravel-bed rivers create a dynamic ecotone called the hyporheic zone. Because it lies between two heavily exploited freshwater resources—rivers and groundwater—the hyporheic zone is vulnerable to impacts coming to it through both of these habitats. This review focuses on the direct and indirect effects of human activity on ecosystem functions of the hyporheic zone. River regulation, mining, agriculture, urban, and industrial activities all have the potential to impair interstitial bacterial and invertebrate biota and disrupt the hydrological connections between the hyporheic zone and stream, groundwater, riparian, and floodplain ecosystems. Until recently, our scientific ignorance of hyporheic processes has perhaps excused the inclusion of this ecotone in river management policy. However, this no longer is the case as we become increasingly aware of the central role that the hyporheic zone plays in the maintenance of water quality and as a habitat and refuge for fauna. To fully understand the impacts of human activity on the hyporheic zone, river managers need to work with scientists to conduct long-term studies over large stretches of river. River rehabilitation and protection strategies need to prevent the degradation of linkages between the hyporheic zone and surrounding habitats while ensuring that it remains isolated from toxicants. Strategies that prevent anthropogenic restriction of exchanges may include the periodic release of environmental flows to flush silt and reoxygenate sediments, maintenance of riparian buffers, effective land use practices, and suitable groundwater and surface water extraction policies. 相似文献
5.
John M. Quinn Paul M. Brown Wendy Boyce Sarah Mackay Andrew Taylor Tony Fenton 《Journal of the American Water Resources Association》2001,37(6):1509-1515
ABSTRACT: Riparian zones perform a variety of biophysical functions that can be managed to reduce the effects of land use on instream habitat and water quality. However, the functions and human uses of riparian zones vary with biophysical factors such as landform, vegetation, and position along the stream continuum. These variations mean that “one size fits all” approaches to riparian management can be ineffective for reducing land use impacts. Thus riparian management planning at the watershed scale requires a framework that can consider spatial differences in riparian functions and human uses We describe a pilot riparian zone classification developed to provide such a framework for riparian management in two diverse river systems in the Waikato region of New Zealand. Ten classes of riparian zones were identified that differed sufficiently in their biophysical features to require different management. Generic “first steps” and “best practical” riparian management recommendations and associated costs were developed for each riparian class. The classification aims to not only improve our understanding of the effectiveness of riparian zone management as a watershed management tool among water managers and land owners, but to also provide a basis for deciding on management actions. 相似文献
6.
Human impacts on the stream-groundwater exchange zone 总被引:13,自引:0,他引:13
Hancock PJ 《Environmental management》2002,29(6):763-781
Active exchanges of water and dissolved material between the stream and groundwater in many porous sand- and gravel-bed rivers
create a dynamic ecotone called the hyporheic zone. Because it lies between two heavily exploited freshwater resources—rivers
and groundwater—the hyporheic zone is vulnerable to impacts coming to it through both of these habitats. This review focuses
on the direct and indirect effects of human activity on ecosystem functions of the hyporheic zone. River regulation, mining,
agriculture, urban, and industrial activities all have the potential to impair interstitial bacterial and invertebrate biota
and disrupt the hydrological connections between the hyporheic zone and stream, groundwater, riparian, and floodplain ecosystems.
Until recently, our scientific ignorance of hyporheic processes has perhaps excused the inclusion of this ecotone in river
management policy. However, this no longer is the case as we become increasingly aware of the central role that the hyporheic
zone plays in the maintenance of water quality and as a habitat and refuge for fauna. To fully understand the impacts of human
activity on the hyporheic zone, river managers need to work with scientists to conduct long-term studies over large stretches
of river. River rehabilitation and protection strategies need to prevent the degradation of linkages between the hyporheic
zone and surrounding habitats while ensuring that it remains isolated from toxicants. Strategies that prevent anthropogenic
restriction of exchanges may include the periodic release of environmental flows to flush silt and reoxygenate sediments,
maintenance of riparian buffers, effective land use practices, and suitable groundwater and surface water extraction policies. 相似文献
7.
Understanding how hydraulic factors control alluvial river meander migration can help resource managers evaluate the long-term
effects of floodplain management and bank stabilization measures. Using a numerical model based on the mechanics of flow and
sediment transport in curved river channels, we predict 50 years of channel migration and suggest the planning and ecological
implications of that migration for a 6.4-km reach (river miles 218–222) of the Sacramento River near the Woodson Bridge State
Recreation Area, California, USA.
Using four different channel management scenarios, our channel migration simulations suggest that: (1) channel stabilization
alters the future channel planform locally and downstream from the stabilization; (2) rock revetment currently on the bank
upstream from the Woodson Bridge recreation area causes more erosion of the channel bank at the recreation area than if the
revetment were not present; (3) relocating the channel to the west and allowing subsequent unconstrained river migration relieves
the erosion pressure in the Woodson Bridge area; (4) the subsequent migration reworks (erodes along one river bank and replaces
new floodplain along the other) 26.5 ha of land; and (5) the river will rework between 8.5 and 48.5 ha of land in the study
reach (over the course of 50 years), depending on the bank stabilization plan used. The reworking of floodplain lands is an
important riparian ecosystem function that maintains habitat heterogeneity, an essential factor for the long-term survival
of several threatened and endangered animal species in the Sacramento River area. 相似文献
8.
Reiner Jaakson 《Journal of the American Water Resources Association》1973,9(6):1225-1233
ABSTRACT: Water-based outdoor recreation constitutes an important benefit in many multiple-use projects. One problem frequently encountered, however, is the fluctuation of the water-level in a reservoir, especially if draw-downs occur during the summer recreation season. The Trent Canal in Ontario, Canada, forms a unique recreation waterway of some 240 miles of canal and navigable lakes and rivers. For the control of the water in the canal, the Canadian Federal government manages 44 reservoir-lakes as water-storage sites to augment the flows in the canal. While most disputes in water allocation for recreation generally involve recreation uses versus other, non-recreation uses, in the case of the Trent Canal and its reservoir-lakes the dispute in water allocation exists between two competing recreation-uses: for recreation boating on the Canal and its waterway, and for recreation use of the reservoir-lakes. Each use has its own duty-of-water in terms of requirements, or water conditions, for its optimum use. On the reservoir-lakes, by far the largest recreation user-group, is made up of the owners of private shoreline summer cottages (cabins). Draw-downs on the reservoir-lakes, in some cases as much as 13 feet, hence constitute a negative externality imposed by the canal, especially since water-level lowering takes place continuously throughout the summer. In-depth interviews conducted with over 100 cottage-owners indicate four main conclusions. First, the previous user assumptions of the extent of the negative effect of water-level fluctuation on recreation had been exaggerated. Only in extreme draw-downs during infrequent dry years would draw-down constitute a serious imposition. Second, water-level fluctuation does constitute a form of inconvenience to the private riparian recreation property owners, but it does not generally reduce the quantity of recreation use of the reservoir-lakes. Third, there is evidence that reservoir-lake users have learned to adapt successfully to water-level draw-downs. Fourth, the shoreline physiography of the location of a riparian owner strongly influences the way in which draw-down affects attitudes and opinions. The complex jurisdictional split of the land and water resources of the region points to the need to establish a Trent Canal Authority, to oversee the proper use and development of the canal, its waterway, and the reservoir-lakes. 相似文献
9.
Daniel A. Auerbach 《Journal of the American Water Resources Association》2013,49(4):973-974
Doyle cogently describes advantages and concerns related to the system of United States river management in the context of its historical and political development. He rightly asserts the need for flexible, adaptable institutions in order to address changing societal demands. However, river management also requires certain inflexible standards in order to discern and prevent practices that undermine future human needs. Where modern scientific evidence converges with cultural traditions of stewardship, river managers can comfortably assert limits to specific patterns of use and to the malleability of restrictions. 相似文献
10.
Basic principles and ecological consequences of changing water regimes: riparian plant communities 总被引:18,自引:1,他引:17
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. 相似文献
11.
Neupane A Boxall PC McFarlane BL Pelletier RT 《Journal of environmental management》2007,85(2):471-482
Fire management agencies in Canada are mandated with protecting multiple forest values from wildfire. Deciding where to reduce fire hazard and how to allocate resources and fire suppression efforts requires an understanding of the values-at-risk from wildfire. The protection of recreation infrastructure is often assumed to provide adequate protection of recreation values. We use an expert judgment approach to provide a spatial distribution of recreation values-at-risk in the forested eastern slopes of the Rocky Mountain region of Alberta, Canada. Data were collected in 2004 from 11 land managers responsible for public lands management and wildfire prevention in the region. Expert assessments showed that recreation values were not confined to areas with publicly funded infrastructure. Exploratory spatial analysis of the ratings identified hotspots and cold spots of recreation activity. Maps resulting from these efforts will provide guidance to fire managers in the prioritization of fire management activities. 相似文献
12.
Unmanaged recreation presents a challenge to both researchers and managers of outdoor recreation in the United States because
it is shrouded in uncertainty resulting from disagreement over the definition of the problem, the strategies for resolving
the problem, and the outcomes of management. Incomplete knowledge about recreation visitors’ values and relationships with
one another, other stakeholders, and the land further complicate the problem. Uncertainty and social complexity make the unmanaged
recreation issue a wicked problem. We describe the wickedness inherent in unmanaged recreation and some of the implications
of wickedness for addressing the problem for the Front Range of the Rocky Mountains in Colorado. Conclusions about the nature
of the problem are based on a problem appraisal that included a literature review and interviews of key informants. Addressing
wickedness calls for institutional changes that allow for and reward the use of trust building, inclusive communication, and
genuinely collaborative processes. 相似文献
13.
Hesseln H Loomis JB González-Cabán A Alexander S 《Journal of environmental management》2003,69(4):359-368
We use a travel cost model to test the effects of wild and prescribed fire on visitation by hikers and mountain bikers in New Mexico. Our results indicate that net benefits for mountain bikers is $150 per trip and that they take an average of 6.2 trips per year. Hikers take 2.8 trips per year with individual net benefits per trip of $130. Both hikers' and mountain bikers' demand functions react adversely to prescribed burning. Net benefits for both groups fall as areas recover from prescribed burns. Because both visitation and annual recreation benefits decrease to these two types of visitors, this gives rise to multiple use costs associated with prescribed burning. With respect to wildfire, hikers and mountain bikers both exhibit decreased visitation as areas recover from wildfires, however, only hikers indicate an increase in per trip net benefits. Bikers' demand effectively drops to zero. These results differ from previous findings in the literature and have implications for efficient implementation of the National Fire Plan and whether prescribed burning is a cost effective tool for multiple use management of National Forests. Specifically, that fire and recreation managers cannot expect recreation users to react similarly to fire across recreation activities, or different geographic regions. What is cost effective in one region may not be so in another. 相似文献
14.
The potential impacts of land use on large woody debris (LWD) were examined in Sourdough Creek Watershed, a rapidly growing
area encompassing Bozeman, Montana, USA. We identified six land classes within a 250 m buffer extending on either side of
Sourdough Creek and assessed aquatic habitat and geomorphologic variables within each class. All LWD pieces were counted,
and we examined 14 other variables, including undercut bank, sinuosity, and substrate composition. LWD numbers were generally
low and ranged from 0 to 8.2 pieces per 50 m of stream. Linear regression showed that LWD increased with distance from headwaters,
riparian forest width, and sinuosity in four of the six land classes. Statistically significant differences between land classes
for many aquatic habitat and geomorphologic variables indicated the impacts of different land uses on stream structure. We
also found that practices such as active wood removal played a key role in LWD abundance. This finding suggests that managers
should prioritize public education and outreach concerning the importance of in-stream wood, especially in mixed-use watersheds
where wood is removed for either aesthetic reasons or to prevent stream flooding. 相似文献
15.
Cerveny LK Blahna DJ Stern MJ Mortimer MJ Predmore SA Freeman J 《Environmental management》2011,48(3):644-657
U.S. Forest Service managers are required to incorporate social and biophysical science information in planning and environmental
analysis. The use of science is mandated by the National Environmental Policy Act, the National Forest Management Act, and
U.S. Forest Service planning rules. Despite the agency’s emphasis on ‘science-based’ decision-making, little is known about
how science is actually used in recreation planning and management. This study investigated the perceptions of Forest Service
interdisciplinary (ID) team leaders for 106 NEPA projects dealing with recreation and travel management between 2005 and 2008.
Our survey data show how managers rate the importance of social and biophysical science compared to other potential ‘success
factors’ in NEPA assessments. We also explore how team leaders value and use multi-disciplinary tools for recreation-related
assessments. Results suggest that managers employ a variety of recreation planning tools in NEPA projects, but there appears
to be no common understanding or approach for how or when these tools are incorporated. The Recreation Opportunity Spectrum
(ROS) was the most frequently used planning tool, but the Visitor Experience and Resource Protection (VERP) framework was
the most consistently valued tool by those who used it. We recommend further evaluation of the strengths and weaknesses of
each planning tool and future development of procedures to select appropriate planning tools for use in recreation-related
NEPA assessments. 相似文献
16.
17.
William E. Hammitt Bjørn P. Kaltenborn Odd Inge Vistad Lars Emmelin Jon Teigland 《Environmental management》1992,16(2):149-156
Many European countries, including Norway, have a right of common access tradition toward wildland areas for recreational
activity. The “right of any one to move freely over all wildlands except farm fields and gardens” can serve as a paradoxical
barrier to managing wildland areas and users for outdoor recreation. This article discusses the apparent paradox between free
access and management of wildland recreation, the underlying principles of both concepts, and proposes an integrative basis
for how the two concepts can serve the same major goal—freedom of access and use of wildland recreation areas without disturbance
to other users or the resource base. A Norwegian field study is presented with campfire data and management strategies to
illustrate the integrative nature of common access and wilderness management principles for the managing of wildland recreation
opportunities. 相似文献
18.
ABSTRACT: Recreation behavior can be examined by identifying characteristics of participants, activities, and places. Two distinct houschold types (social groups) were examined relative to their participation in water based recreation: households whose participation occurs exclusively in water based recreation, and those reporting participation in both water and nonwater activities. These households were compared in terms of preference for and specialization in water recreation, the relationship of water activity selected and resource (place) preference and intensity of participation in water activities. Attention by managers, planners, and social scientists to the interplay of participant group, activity, and place upon behavioral outcomes is important to the future development of recreation opportunities. It is one thing to design a facility for water based recreation; it is another to design a facility knowing the behavioral outcomes occurring and how they will be affected. Similarly, to implement a management strategy without knowing how behavior of participants will be modified as a result of the strategy can lead to failure of the management objective. 相似文献
19.
We assessed the relationship between riparian management and stream quality along five southeastern Minnesota streams in 1995
and 1996. Specifically, we examined the effect of rotationally and continuously grazed pastures and different types of riparian
buffer strips on water chemistry, physical habitat, benthic macroinvertebrates, and fish as indicators of stream quality.
We collected data at 17 sites under different combinations of grazing and riparian management, using a longitudinal design
on three streams and a paired watershed design on two others. Continuous and rotational grazing were compared along one longitudinal
study stream and at the paired watershed. Riparian buffer management, fenced trees (wood buffer), fenced grass, and unfenced
rotationally grazed areas were the focus along the two remaining longitudinal streams. Principal components analysis (PCA)
of water chemistry, physical habitat, and biotic data indicated a local management effect. The ordinations separated continuous
grazing from sites with rotational grazing and sites with wood buffers from those with grass buffers or rotationally grazed
areas. Fecal coliform and turbidity were consistently higher at continuously grazed than rotationally grazed sites. Percent
fines in the streambed were significantly higher at sites with wood buffers than grass and rotationally grazed areas, and
canopy cover was similar at sites with wood and grass buffers. Benthic macroinvertebrate metrics were significant but were
not consistent across grazing and riparian buffer management types. Fish density and abundance were related to riparian buffer
type, rather than grazing practices. Our study has potentially important implications for stream restoration programs in the
midwestern United States. Our comparisons suggest further consideration and study of a combination of grass and wood riparian
buffer strips as midwestern stream management options, rather than universally installing wood buffers in every instance.
RID=" ID=" The Unit is jointly sponsored by the US Geological Survey, Biological Resources Division; the Minnesota Department
of Natural Resources; the University of Minnesota; and the Wildlife Management Institute. 相似文献
20.
A lidar-based assessment of riparian shade and large wood potential in the Skagit River watershed,WA
Tim Hyatt 《Journal of the American Water Resources Association》2023,59(4):743-761
Wild salmon stocks in the Pacific Northwest are imperiled by a variety of declining habitat factors, including riparian shade and in-channel large wood. In this paper, a relatively simple lidar model of the riparian canopy was used along anadromous streams in the Skagit River watershed in western Washington State, United States, to delineate where riparian trees were most lacking, and where restoration efforts would have the greatest benefit in terms of shade and large wood recruitment potential. Within a 45-m riparian buffer, 61% of riparian zones were currently incapable of delivering large wood to the stream. Current potential for large wood recruitment is greatest adjacent to stream edges and falls off rapidly with distance from the channel. Approximately 99% of large wood recruitment potential lies within 45 m of the channel edge, and 50% of the wood potential is within 9 m. A hypothetical canopy model in which all trees mature to a 100-year height would provide 18% more shade distributed over the entire watershed, and 90% more shade in the tributaries. Most of the potential gains in improved shade and large wood contributions are in agricultural areas, as opposed to forestry or urban land uses. The shade and large wood models were constructed from widely available geographic information system tools and are readily transferable to other watersheds with similar characteristics. Model outputs are intended for use in planning restoration projects, as an input to stream temperature models, and to inform policy on restoration priorities and regulatory buffer widths. 相似文献