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41.
Chelsey Walden-Schreiner Sebastian Dario Rossi Agustina Barros Catherine Pickering Yu-Fai Leung 《Ambio》2018,47(7):781-793
Managing protected areas effectively requires information about patterns of visitor use, but these data are often limited. We explore how geotagged photos on Flickr, a popular photo-sharing social-media site, can generate hotspot maps and distribution models of temporal and spatial patterns of use in two mountain-protected areas of high conservation value. In Aconcagua Provincial Park (Argentina), two routes to the summit of Aconcagua were used in summer, but most visitors stayed close to the main road, using formal and informal walking trails and the Visitor Centre, while in winter, there was very limited visitation. In Kosciuszko National Park (Australia), alpine walking trails were popular in summer, but in winter, most visitors stayed in the lower altitude ski resorts and ski trails. Results demonstrate the usefulness of social-media data alone as well as a complement for visitor monitoring, providing spatial and temporal information for site-specific and park-level management of visitors and potential impacts in conservation areas. 相似文献
42.
Comparing hiking,mountain biking and horse riding impacts on vegetation and soils in Australia and the United States of America 总被引:1,自引:0,他引:1
Catherine Marina Pickering Wendy Hill David Newsome Yu-Fai Leung 《Journal of environmental management》2010,91(3):551-562
Hiking, horse riding and mountain biking are popular in protected areas in Australia and the United States of America. To help inform the often contentious deliberations about use of protected areas for these three types of activities, we review recreation ecology research in both countries. Many impacts on vegetation, soils and trails are similar for the three activities, although there can be differences in severity. Impacts include damage to existing trails, soil erosion, compaction and nutrification, changes in hydrology, trail widening, exposure of roots, rocks and bedrock. There can be damage to plants including reduction in vegetation height and biomass, changes in species composition, creation of informal trails and the spread of weeds and plant pathogens. Due to differences in evolutionary history, impacts on soil and vegetation can be greater in Australia than in the USA. There are specific social and biophysical impacts of horses such as those associated with manure and urine, grazing and the construction and use of tethering yards and fences. Mountain bike specific impacts include soil and vegetation damage from skidding and the construction of unauthorised trails, jumps, bridges and other trail technical features. There are gaps in the current research that should be filled by additional research: (1) on horse and mountain bike impacts to complement those on hiking. The methods used need to reflect patterns of actual usage and be suitable for robust statistical analysis; (2) that directly compares types and severity of impacts among activities; and (3) on the potential for each activity to contribute to the spread of weeds and plant pathogens. Additional research will assist managers and users of protected areas in understanding the relative impacts of these activities, and better ways to manage them. It may not quell the debates among users, managers and conservationists, but it will help put it on a more scientific footing. 相似文献
43.
Catherine Marina Pickering 《Ambio》2010,39(1):70-77
Protected areas represent the major method for conserving biodiversity. However, visitor use can threaten their conservation
value. Based on a review of recent research, I have categorized factors that affect the severity of environmental impacts
of visitor use. These factors need to be considered or evaluated when assessing visitor use of sites in protected areas. They
are: (i) the conservation value of the site, (ii) its resistance to use, (iii) its recovery from use, (iv) its susceptibility
to erosion, (v) the severity of direct impacts associated with specific activities, (vi) the severity of indirect impacts,
(vii) the amount of use, (viii) the social and (ix) ecological dimensions to the timing of use, and (x) the total area affected.
Although the factors may not be of equal importance or necessarily assessed on an equal scale, they allow people to make more
informed assessments of potential impacts, assist in identifying where monitoring may be required, and indicate where additional
site- or activity-specific research may be appropriate. 相似文献
44.
Management effectiveness evaluation has been recognized as an important mechanism for both reporting on and improving protected
area management. The Convention on Biological Diversity’s program of work on protected areas calls on all countries to implement
such systems. In 2004, the first whole of system assessment of park management effectiveness, based on the IUCN-WCPA Management
Effectiveness Evaluation Framework, was undertaken in New South Wales, Australia as part of a State of the Parks reporting
requirement. This article describes the development of the State of the Parks assessment tool, its elements, and how it addresses
the management effectiveness difficulties associated with assessments conducted across an extensive and diverse range of park
types. The importance of engaging staff, at all levels, throughout the process is highlighted, as well as the adjustments
made to the assessment tool based on staff feedback. While some results are presented, the main purpose of the article is
to identify and discuss important procedural and methodological considerations. These include balancing quantitative and qualitative
assessment approaches, achieving a comprehensive understanding of the management processes, and responding to any problems
associated with assessments. 相似文献
45.
Brent Johnson Elizabeth Smith Jerry W. Ackerman Susan Dye Robyn Polinsky Eric Somerville Chris Decker Derek Little Gregory J. Pond Ellen D'Amico 《Journal of the American Water Resources Association》2019,55(1):247-258
Spatial patterns in major dissolved solute concentrations were examined to better understand impact of surface coal mining in headwaters on downstream water chemistry. Sixty sites were sampled seasonally from 2012 to 2014 in an eastern Kentucky watershed. Watershed areas (WA) ranged from 1.6 to 400.5 km2 and were mostly forested (58%–95%), but some drained as much as 31% surface mining. Measures of total dissolved solutes and most component ions were positively correlated with mining. Analytes showed strong convergent spatial patterns with high variability in headwaters (<15 km2 WA) that stabilized downstream (WA > 75 km2), indicating hydrologic mixing primarily controls downstream values. Mean headwater solute concentrations were a good predictor of downstream values, with % differences ranging from 0.55% (Na+) to 28.78% (Mg2+). In a mined scenario where all headwaters had impacts, downstream solute concentrations roughly doubled. Alternatively, if mining impacts to headwaters were minimized, downstream solute concentrations better approximated the 300 μS/cm conductivity criterion deemed protective of aquatic life. Temporal variability also had convergent spatial patterns and mined streams were less variable due to unnaturally stable hydrology. The highly conserved nature of dissolved solutes from mining activities and lack of viable treatment options suggest forested, unmined watersheds would provide dilution that would be protective of downstream aquatic life. 相似文献
46.
Lee J Rao PS Poyer IC Toole RM Annable MD Hatfield K 《Journal of contaminant hydrology》2007,92(3-4):208-229
We report here on the extension of Passive Flux Meter (PFM) applications for measuring fluxes of oxyanions in groundwater, and present results for laboratory and field studies. Granular activated carbon, with and without impregnated silver (GAC and SI-GAC, respectively), was modified with a cationic surfactant, hexadecyltrimethylammonium (HDTMA), to enhance the anion exchange capacity (AEC). Langmuir isotherm sorption maxima for oxyanions measured in batch experiments were in the following order: perchlorate>chromate>selenate, consistent with their selectivity. Linear sorption isotherms for several alcohols suggest that surfactant modification of GAC and SI-GAC reduced (approximately 30-45%) sorption of alcohols by GAC. Water and oxyanion fluxes (perchlorate and chromate) measured by deploying PFMs packed with surfactant-modified GAC (SM-GAC) or surfactant-modified, silver-impregnated GAC (SM-SI-GAC) in laboratory flow chambers were in close agreement with the imposed fluxes. The use of SM-SI-GAC as a PFM sorbent was evaluated at a field site with perchlorate contamination of a shallow unconfined aquifer. PFMs packed with SM-SI-GAC were deployed in three existing monitoring wells with a perchlorate concentration range of approximately 2.5 to 190 mg/L. PFM-measured, depth-averaged, groundwater fluxes ranged from 1.8 to 7.6 cm/day, while depth-averaged perchlorate fluxes varied from 0.22 to 1.7 g/m2/day. Groundwater and perchlorate flux distributions measured in two PFM deployments closely matched each other. Depth-averaged Darcy fluxes measured with PFMs were in line with an estimate from a borehole dilution test, but much smaller than those based on hydraulic conductivity and head gradients; this is likely due to flow divergence caused by well-screen clogging. Flux-averaged perchlorate concentrations measured with PFM deployments matched concentrations in groundwater samples taken from one well, but not in two other wells, pointing to the need for additional field testing. Use of the surfactant-modified GACs for measuring fluxes of other anions of environmental interest is discussed. 相似文献
47.
Impacts of recreation and tourism on plant biodiversity and vegetation in protected areas in Australia 总被引:4,自引:0,他引:4
This paper reviews recent research into the impact of recreation and tourism in protected areas on plant biodiversity and vegetation communities in Australia. Despite the international significance of the Australian flora and increasing visitation to protected areas there has been limited research on recreational and tourism impacts in Australia. As overseas, there are obvious direct impacts of recreation and tourism such as clearing of vegetation for infrastructure or damage from trampling, horse riding, mountain biking and off road vehicles. As well, there are less obvious but potentially more severe indirect impacts. This includes self-propagating impacts associated with the spread of some weeds from trails and roads. It also includes the severe impact on native vegetation, including many rare and threatened plants, from spread of the root rot fungus Phytopthora cinnamomi. This review highlights the need for more recreational ecology research in Australia. 相似文献
48.
Ecological indicators can facilitate an adaptive management approach, but only if acceptable levels for those indicators have
been defined so that the data collected can be interpreted. Because acceptable levels are an expression of the desired state
of the ecosystem, the process of establishing acceptable levels should incorporate not just ecological understanding but also
societal values. The goal of this research was to explore an approach for defining acceptable levels of ecological indicators
that explicitly considers social perspectives and values. We used a set of eight indicators that were related to issues of
concern in the Lake Champlain Basin. Our approach was based on normative theory. Using a stakeholder survey, we measured respondent
normative evaluations of varying levels of our indicators. Aggregated social norm curves were used to determine the level
at which indicator values shifted from acceptable to unacceptable conditions. For seven of the eight indicators, clear preferences
were interpretable from these norm curves. For example, closures of public beaches because of bacterial contamination and
days of intense algae bloom went from acceptable to unacceptable at 7–10 days in a summer season. Survey respondents also
indicated that the number of fish caught from Lake Champlain that could be safely consumed each month was unacceptably low
and the number of streams draining into the lake that were impaired by storm water was unacceptably high. If indicators that
translate ecological conditions into social consequences are carefully selected, we believe the normative approach has considerable
merit for defining acceptable levels of valued ecological system components. 相似文献
49.
James O. Luken Steven W. Beiting Scott K. Kareth Robyn L. Kumler Jun H. Liu Craig A. Seither 《Environmental management》1994,18(2):251-255
We tested two cutting regimens (cut/spray and cut/delay spray) and four radiarc-applied herbicides (Garlon + Tordon, Accord,
Accord + Escort, and Krenite) in an Ohio power-line corridor to determine which management combination best eliminated target
species (i.e., trees) and preserved nontarget species (i.e., low shrubs, vines, perennial herbs, and grasses).
When spraying was delayed after cutting, the herbicide with the least impact on nontarget species (Krenite) also was least
efficient at killing target trees. Spraying soon after cutting improved tree-killing efficiency of several herbicides, but
it also increased the negative impact on nontarget species. The herbicide with the most consistent tree-killing ability (Accord
+ Escort) had the most impact on nontarget species.
Because none of the herbicide/cutting treatments performed ideally, resource managers must decide the acceptable impact on
nontarget species when considering herbicide use. Future success of herbicides as part of an integrated succession management
approach requires more selective application methods and formulations so that target effects can be maximized and nontarget
effects can be minimized. 相似文献
50.
The persistence of an island of remnant vegetation within a tailings retention system provided an opportunity to conduct a pilot study to develop hypothesis concerning the impacts of acid spray and radiation on arid zone flora and fauna. Ecological changes were investigated by comparing species abundance and condition on both the study island and remote control areas. Hopbush (Dodonaea viscosa), geckos and a common ant species, Iridomyrmex rufoniger sp. B were abundant in control regions but absent from the study region, whereas densities of colonising plant species, Helea beetles and scorpions were unusually high at the impacted site. These disparities are probably attributable to acid spray at the impacted site and hence are potentially useful bioindicators of these impacts. Dragon and skink populations were apparently unaffected by the polluted ecosystem, although Ctenophorus nuchalis proved to be a significant bioaccumulator of radionuclides. Bioaccumulation of the radionuclides, 238U, 230Th, 210Pb and particularly 210Po were significantly greater than that reported elsewhere in the literature. Further radionuclide monitoring of herbivorous dragon species, possibly concentrating upon 210Po levels, was the suggested outcome of this pilot study. 相似文献