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1.
Arnaud Grüss David M. Kaplan Sylvie Guénette Callum M. Roberts Louis W. Botsford 《Biological conservation》2011,(2):692-702
Adult and juvenile mobility has a considerable influence on the functioning of marine protected areas. It is recognized that adult and juvenile movement reduces the core benefits of protected areas, namely protecting the full age–structure of marine populations, while at the same time perhaps improving fisheries yield over the no-reserve situation through export of individuals from protected areas. Nevertheless, the study of the consequences of movement on protected area functioning is unbalanced. Significant attention has been paid to the influence of certain movement patterns, such as diffusive movement and home ranges, while the impacts of others, such as density-dependent movements and ontogenetic migrations, have been relatively ignored. Here we review the diversity of density-independent and density-dependent movement patterns, as well as what is currently known about their consequences for the conservation and fisheries effects of marine protected areas. We highlight a number of ‘partially addressed’ issues in marine protected area research, such as the effects of reserves targeting specific life phases, and a number of essentially unstudied issues, such as density-dependent movements, nomadism, ontogenetic migrations, behavioral polymorphism and ‘dynamic’ reserves that adjust location as a realtime response to habitat changes. Assessing these issues will be essential to creating effective marine protected area networks for mobile species and accurately assessing reserve impacts on these species. 相似文献
2.
A quantitative method for evaluating the importance of marine areas for conservation of birds 总被引:1,自引:0,他引:1
Objective criteria are needed for ranking marine sites when examining candidate areas for protection measures. We suggest a Marine Classification Criterion (MCC) which allows the application of the widely used Ramsar 1% criterion for wetlands for seabirds with clustered distribution in offshore habitats. The maximum size of an area considered to be internationally important has not been defined by the Ramsar Convention. Terrestrial and coastal sites generally have obvious hydrological or physical boundaries, whereas such boundaries are less obvious at sea. The smallest unit which would pass the demands set by the MCC is 1% of the bio-geographic population of a particular species concentrated in an area (site) supporting a density exceeding a value equivalent of four times the average density of the species in the investigated regional sea. The effect of choosing smaller or larger reference densities is tested. The results indicate that the chosen threshold density is a suitable requirement for the inclusion of the most important areas for seabird species with at least 25% of their bio-geographic population occurring in the studied regions of the North Sea and the Baltic Sea. The test cases indicate that provided the MCC is based on geo-statistical analyses of un-biased survey data the boundaries of areas holding large concentrations of seabirds can be estimated with confidence. The MCC could be used to identify concentrations of seabirds and other marine animals of conservation priority and to rank marine areas by their cumulative importance to different species. 相似文献
3.
Anthropogenic modification of natural habitat is resulting in a widespread loss of biodiversity. One of the primary responses of human societies to biodiversity loss has been the creation of protected areas. Two of the most important questions in conservation biology are: (1) whether protected areas are playing their intended role as reservoirs of biodiversity; and (2) whether habitat outside protected areas, particularly in agricultural landscapes, plays a significant role in maintaining biodiversity and the ecosystem services that it provides. Even though empirical evidence is still lacking on the exact mapping from functional group richness to specific ecosystem services, functional groups are good indicators of ecosystem functioning and thus service provision. We classified the South African avifauna into nine functional groups and tested at a coarse grain for differences in functional group composition between landscapes containing predominantly agricultural vs. protected areas. We used a matched pair sampling design to control for confounding variance. We found that avian functional groups respond in quantitatively and qualitatively distinct ways to agriculturally dominated landscapes. Raptors and scavengers displayed the most consistent losses, while nutrient dispersers and grazers tended to increase. Spatial detrending and randomisation tests suggested that only raptors and scavengers are negatively affected by agricultural landscapes independently of spatial autocorrelation. Thus, protected area landscapes are serving as important reservoirs of functionally important upper trophic populations while agricultural landscapes facilitate the presence of species that link aquatic and terrestrial systems. These results demonstrate the potential for complementary facets of functional diversity to exist on landscapes containing vastly different land-uses. 相似文献
4.
Protected areas are often proposed as tools for conserving endangered populations of marine megafauna. Our study area includes a voluntary no-entry reserve embedded within wider critical habitat for Threatened ‘northern resident’ killer whales under Canada’s Species at Risk Act. Our study quantified the reserve’s importance to whales by assessing habitat preference in a behavioural context, and population-level implications of that preference given threats from human activities, such as oil spills resulting from shipping traffic. We recorded summertime activities of whales from 1995 to 2002. Whales were observed on 397 of 530 (74.9%) days. Whales showed strong preference for the reserve over adjacent waters, and used it preferentially for feeding and beach-rubbing. While the area comprises ∼0.001% of the whales’ range, an overall average of 6.5% of the population was present each day. Frequently, >50% of this small population was aggregated in the restricted and heavily trafficked waterway of Johnstone Strait. Using the Potential Biological Removal equation, we calculated potential annual mortality limits (ML) of 2.2 animals. Mean group size in the area exceeded ML on 55.8% of days overall, and 98.8% of days when conditioning on whale presence. The whales’ high reliance on a trivial fraction of their range means that opportunities are routine for one stochastic, catastrophic event to cause population decline. On 20 August 2007, a barge loaded with ∼10,000 L of diesel sank in the area, exposing 25% of the population. This underscores the importance of identifying critical habitat for threatened populations, and ensuring meaningful protection. 相似文献
5.
Vanessa M. Adams Morena Mills Stacy D. Jupiter Robert L. Pressey 《Biological conservation》2011,(1):350-361
We present a novel method for calculating the opportunity costs to fishers from their displacement by the establishment of marine protected areas (MPAs). We used a fishing community in Kubulau District, Fiji to demonstrate this method. We modelled opportunity costs as a function of food fish abundance and probability of catch, based on gear type and market value of species. Count models (including Poisson, negative binomial and two zero-inflated models) were used to predict spatial abundance of preferred target fish species and were validated against field surveys. A profit model was used to investigate the effect of restricted access to transport on costs to fishers. Spatial distributions of fish within the three most frequently sighted food fish families (Acanthuridae, Lutjanidae, Scaridae) varied, with greatest densities of Lutjanidae and Acanthuridae on barrier forereefs and greatest densities of Scaridae on submerged reefs. Modelled opportunity cost indicated that highest costs to fishers arise from restricting access to the barrier forereefs. We included our opportunity cost model in Marxan, a decision support tool used for MPA design, to examine potential MPA configurations for Kubulau District, Fiji Islands. We identified optimum areas for protection in Kubulau with: (a) the current MPA network locked in place; and (b) a clean-slate approach. Our method of modelling opportunity cost gives an unbiased estimate for multiple gear types in a marine environment and can be applied to other regions using existing species data. 相似文献
6.
In the north Adriatic Sea on-board observations on midwater and bottom trawlers were carried out during years 1999 and 2000. Results indicate that the north Adriatic Sea, and especially the north-east part, is a very important foraging and overwintering habitat for loggerhead turtles (Caretta caretta). Since the distribution of fishing effort in the area is not known, the total turtle catch by the Italian bottom trawl fleet was conservatively estimated from the lower catch rate observed in the south-west sub-area: 4273 turtle captures/year (95% C.I.=2186-8546). The actual total catch in the whole north Adriatic is likely to be much higher, due both to an unknown Italian trawling effort in the south-west part with multi-gear vessels and to the Italian and Croatian trawling efforts in the north-east part, where catch rate was 15 times greater than in the south-west part. In the south-west sub-area 9.4% of captured turtles were dead and potential mortality (assuming that all comatose turtles would die too) was 43.8%. Hence, trawling in the north Adriatic is likely to represent a serious threat to the populations, and possible conservation measures are discussed. 相似文献
7.
Western Australia has an extensive coastline ranging from the tropical north to the temperate south, with a high diversity of neritic marine fishes. Distribution data of 1855 neritic fish species were used to compare a range of methods for identifying priority areas for their conservation. Species richness and endemism richness hotspots, biogeographic zoning and complementarity analysis were tested for their efficiency at representing the total suite of species. The hotspot approaches demonstrated low efficiency, as the sections of coastline selected were grouped together in isolated geographic locations and relatively few of the total suite of neritic fish species were represented. Biogeographic zoning divided the coast of Western Australia into six regions, and as such, priority areas were selected around the entire coastline, which resulted in fairly high levels of efficiency. However, the complementarity analysis proved to be the most efficient method, as >95% of all neritic fish species could be represented in six, appropriately located, 100 km long sections of coastline. Complementarity analysis indicated a total of 26 priority areas for neritic fish conservation, which were spread around the entire coast of Western Australia. However, as current marine conservation measures in Western Australia are focused on the west and northwest coasts, this study highlighted the need for marine conservation efforts to be extended to cover the north and south coasts. 相似文献
8.
Satellite tracking devices were used to examine the at sea movements of southern and northern giant petrels from Macquarie Island during the Austral summers of 2005-06 and 2006-07. Time spent at sea for nine northern giant petrels (four breeding adults, five recently fledged juveniles) and 10 southern giant petrels (three breeding adults, one non-breeding adult, and six recently fledged juveniles) was examined in relation to marine protected areas and fishing activity in the area immediately adjacent to Macquarie Island in 2005-06, and in terms of the jurisdictions of Regional Fisheries Management Authorities (RFMOs) at a broader scale during both seasons. Breeding adult southern and northern giant petrels spent a large proportion of their time at sea in the Macquarie Island Marine Park (25% and 65%, respectively), primarily during chick rearing. Further from Macquarie Island, the most important foraging areas for adult giant petrels were the Commission for the Conservation of Antarctic Marine Living Resources (CCAMLR) statistical sub-areas 58.4.1 and 88.1, where foraging activity was concentrated around the ice edge and the Polar Frontal Zone. Fledglings of both species spent time in the Marine Park immediately after fledging, before moving into international waters. We found significant temporal and spatial overlap in the areas used by recently fledged juvenile northern giant petrels and the areas utilised by the single trawler that operated in these waters during 2005-06. Adult giant petrels spent little time in RFMO waters other than those under the jurisdiction of CCAMLR, but fledgling southern and northern giant petrels spent considerable time (56% and 78% of total time at sea) on the high seas of the Pacific Ocean, in areas under the jurisdictions of the Commission for the Conservation of Southern Bluefin Tuna (CCSBT), the Western and Central Pacific Fisheries Commission (WCPFC), the Inter American Tropical Tuna Commission (IATTC) and the South Pacific Regional Fisheries Management Organisation (SPRFMO). Band returns indicate that the International Commission for the Conservation of Atlantic Tunas (ICCAT) and the South East Atlantic Fisheries Organisation (SEAFO) areas are likely to be extensively utilised by Macquarie Island giant petrels in the first three years after fledging. Overall, Macquarie Island’s giant petrel populations are well protected by marine reserves during the breeding season. However, after fledging birds move into RFMO areas that currently have low standards of observer coverage and by catch mitigation, and where fisheries related mortality is likely to pose a significant risk. 相似文献
9.
Sylvaine Giakoumi Hedley S. Grantham Giorgos D. Kokkoris Hugh P. Possingham 《Biological conservation》2011,(2):753-763
The present study is the first to determine priorities for the location of marine reserves using spatial prioritization software in the eastern Mediterranean Sea. We used biophysical data from visual census surveys on: fish species abundance, presence of various habitat types, and percent coverage of seagrasses and canopy algae. Efficient conservation planning requires spatially explicit information on how proposed management will affect stakeholders, which in this region was very limited. We created novel socio-economic cost indices to account for fisheries and tourists. Our fishing metrics were based on fisher behaviour including information on the location of ports and areas often inaccessible to fishers due to high wind exposure. We developed a cost index for tourism based on the availability of beds for tourists. We examined how the spatial priorities for marine reserves varied using different combinations of these socio-economic cost metrics. We found about 17% of sites were a high priority regardless of which cost metric was used. We also compared, for the first time in the Mediterranean, our results devised using systematic conservation planning approaches with priorities developed by two non-systematic methods, the Natura 2000 proposed marine reserves and sites that local fishers proposed for protection. Only a few sites identified by our approach were the same as those recommended as part of Natura 2000 or the fishers’ proposals. This suggests that much more work is needed to harmonise existing proposals with the principles of efficient systematic conservation planning. 相似文献
10.
Marcelo F. Tognelli Miriam Fernández Pablo A. Marquet 《Biological conservation》2009,142(12):3147-1050
The growing concern about the profound influence of human activities on marine ecosystems has been the driving force behind the creation of marine reserves in the last few decades. With almost 4200 km of coastline, Chile has not been the exception to this trend. A set of conservation priority sites has recently been proposed by the Chilean government to expand the current marine reserve network. In this study, we used the most comprehensive information currently available on the distribution of 2513 marine species in Chile to assess the efficiency of the existing system of marine protected areas (MPA) and the conservation priority sites identified by the government. Additionally, we evaluated the vulnerability of the reserve network selected with respect to threatening human activities. Our results show that both the existing protected areas and the proposed priority sites are relatively effective at protecting Chilean marine biodiversity. However, the majority of the species that are not represented within the existing or projected MPA network have very restricted distributions and are, therefore, of high conservation concern. To cover all species requires a network of 35 MPAs (46% of the total number of planning units). Many of the sites identified as irreplaceable present conflict with one or more human activities, particularly in the central region of the country. This study emphasizes the need for a systematic conservation planning approach to maximize the representation of species and prioritize those areas where conflicts between marine biodiversity conservation and human activities may occur. 相似文献
11.
Populations of a protandric limpet, Cymbula oculus, were compared between two South African Marine Protected Areas (MPAs), Dwesa and Tsitsikamma, and four exploited sites, and between sites exposed to or sheltered from strong wave action. Harvesting is decimating populations of this limpet. Compared with harvested sites, limpets in MPAs were 30-50% larger, adult densities 75% greater and biomass 30-90% greater. The female:male ratio was 0.58:1 inside the MPAs, but 0.11:1 at harvested sites. Growth rate and age-at-maturity were unaffected by harvesting, but survivorship was 10-fold higher inside MPAs, and reproductive output a staggering 80-fold higher. Conversely, recruitment was three times higher in harvested than protected areas, and inversely correlated with adult density. Wave action had negative effects of similar magnitude to harvesting. Limpets at sheltered sites were 65% larger, biomass 80% greater, female proportions 40% higher, survivorship 25% greater and growth 33% greater. Recruitment was, however, 45% greater at wave-exposed sites. All these effects were detected only inside the MPAs, being masked by harvesting elsewhere. The impacts of harvesting and wave action could never have been detected without the existence of MPAs, emphasizing their importance for base-line studies as well as protection. Dwesa MPA is under threat from poaching and demands for access to resources, but a strong case exists for retaining at least a core fully protected area. Our results clearly illustrate the need for MPAs among the tools used for coastal management. 相似文献
12.
Marine protected areas (MPAs) are increasingly envisaged as a tool to manage coastal ecosystems and fisheries. Assessment of their performance with respect to management objectives is therefore important. A number of MPAs provided conservation benefits for fished species. Observed benefits do not apply to all species at all times, and responses to protection are also highly variable among fish taxa. Among the many empirical studies on marine reserves, only a few designs considered ‘before and after data’ and spatial variation. In this paper, we are interested in assessing the effect of a no-take reserve on the reef fish assemblage in a northwestern Mediterranean example. Data were obtained from a three-year survey using underwater visual censuses (UVC), before and after MPA establishment. Permutational multivariate analysis of variance (PERMANOVA) and multivariate regression trees (MRT) were used to evaluate the effects of reserve protection on the reef fish assemblage, while accounting for habitat. Modelled biological responses were abundances and diversity indices calculated at different levels of the assemblage. Significant effects were found for many of these metrics. In addition to PERMANOVA, univariate models provided more insight into the magnitude and direction of effects. The most sensitive metrics were related to large species and species targeted by fishing. These results may be used to choose the metrics that are more suitable as community-based indicators of MPA impact in the perspective of monitoring programs. 相似文献
13.
We assessed home range size for breeding loggerhead turtles (Caretta caretta) near the limit of the species range at the Greek island of Zakynthos in the Mediterranean. Thirteen adult females and seven adult males were tracked using GPS units (loggers and transmitters) during May and June of 2006, 2007 and 2008. Kernel analysis indicated that core home range sizes (50% estimator; range: 2.9-19.7 km2) for both males and females were restricted to a 7.5 km tract of coastline. 15% of GPS locations fell outside of the national park protection zones, while within the protected breeding area 88% of GPS locations occurred in zones of minimal protection. Female home ranges were 64% larger in 2008 than in 2006 and 2007, indicating that several years monitoring may be required for the most effective designation of marine protected areas (MPAs). Ten of the tracked females departed the core breeding area on 15 occasions for periods of 1-15 days travelling distances of 10-100 km, although none nested at alternative breeding sites. The inter-annual variability of breeding area home range size and likelihood of incidence of forays appeared be correlated with barometric pressure. The movement responses of loggerheads to environmental conditions implicates an ability to switch nesting areas over small scales in response to climate change. However, such behaviour suggests the protection of existing core breeding sites may be inadequate, with policy makers being required to consider the protection of broader areas to encompass potential changes in the habitat needs of this species. 相似文献
14.
The buffer effect predicts that where the reproductive success and survivorship of a species vary between potential habitats, sites will be sequentially filled according to a preference hierarchy. Once favoured sites reach saturation, numbers on the less-suitable/poorer quality sites will show a greater rate of increase compared with those on favoured sites. Supporting evidence for a buffer effect is readily available in the literature for many species, although this is generally restricted to small-scale analyses. In this paper we test for a buffer effect on a national scale for 19 species of waterbirds regularly wintering in the UK for which populations have increased nationally. The results provide little support for the effect, with only four species showing significant negative correlations. Nonetheless, a number of factors are likely to confound the occurrence/identification of a buffer effect for these species, including site area and data limitations. By contrast, for the majority of these 19 species, those sites where initial population totals are largest are also those with the fastest rates of population increase. Encouragingly, these sites are, therefore, more likely to be classified and managed as Special Protection Areas (SPAs) or Ramsar sites using the current numerical criteria for identifying such conservation areas. 相似文献
15.
Climate and land-use changes are expected to cause many species to shift into or beyond the boundaries of protected areas, leading to large turnover in species composition. Here, we tested whether long-established protected areas in Canada were more robust to such climate change impacts than areas with no formal protection by measuring changes in modeled butterfly species distributions (n = 139) within them. We used a recently established distribution modeling technique, Maxent, to model butterfly species’ distributions in two epochs (1900-1930 and 1960-1990). We compared rates of butterfly species richness and composition change within protected areas against distributions of randomly selected, ecologically similar, but non-protected, areas. Change in species richness and composition within protected areas were, for the most part, the same as changes observed among random areas outside protected area boundaries. These results suggest that existing protected area networks in Canada have provided little buffer against the impacts of climate change on butterfly species richness, possibly because land-use change surrounding long-standing protected areas has not been substantial enough to elevate the habitat protection afforded by these protected areas relative to other areas. Although protected areas are unarguably beneficial in conserving biological diversity, their capacity to maintain habitat appears insufficient to prevent broader-scale climate changes from sweeping species beyond their boundaries. 相似文献
16.
Two key questions regarding “no-take” marine reserves are: (1) how effective are reserves likely to be, and (2) how does effectiveness vary with life history attributes and the relative size of reserves. To investigate these questions, we use a simple Ricker model that includes fishing, larval dispersal, and larval loss while in a planktonic pool, and that tracks protected and unprotected populations. We applied two different measures of reserve effectiveness to our simulation results. One metric was intended to reflect goals oriented towards conservation and the second was intended to reflect fishery enhancement goals. Both metrics compare the situation before reserves are established to after the reserve has been in place and a new equilibrium was reached. Yield effectiveness is defined as the total equilibrium annual harvest after reserves are established divided by the total annual harvest before reserves are established. Conservation effectiveness is defined as the average adult density inside the reserve divided by the average density in the same area prior to reserve establishment. A substantial fraction of the 5120 simulated parameter combinations representing different harvest rates and life history attributes went extinct in the absence of a reserve, and these scenarios leading to extinction could be predicted accurately (85% aptly classified) simply on the basis of exploitation rate and population growth rate. Of the cases that did not go extinct, we compared the performance of reserves as measured by each effectiveness metric. Few of the cases (less than 8%) produced effective reserves as measured in terms of increased harvest; whereas over half of the cases resulted in effective reserves as measured by conservation effectiveness. Moreover, the two measures of reserve effectiveness were only weakly correlated. Simple linear regression or polynomial regression could explain at most 23% of the variation in reserve effectiveness as measured by either metric. As expected, the size of the reserve area had a marked and typically negative effect on total annual yield, which suggests that while marine protected areas may do a good job of conserving protected populations, there will generally be pressure from the fishing community to keep them small because of their tendency to reduce total catch. 相似文献
17.
Understanding population differentiation and genetic diversity within population is critical to the development of conservation programmes for threatened species. The protected species, Anchusa crispa Viv. occurs on coastal sand dunes in three disjunct geographical groups of populations: two populations on the east coast of Corsica, several populations around a single estuary on the west coast of Corsica and at a number of sites in north-west Sardinia, where two different subspecies occur. In this study we quantify differentiation of reproductive traits and isozymes among regions and populations on Corsica and between subspecies on Sardinia. No isozyme variation was detected within any of the studied populations nor among populations from a given geographic region. Two loci showed geographic differentiation between regions on Corsica. On Sardinia, the two subspecies showed no isozyme differentiation, and, depending on the loci examined, are similar to one or other of the two regions on Corsica. Reproductive traits show significant differentiation between geographic regions on Corsica, but little variation among populations within a region. In populations on the west coast of Corsica, flowers are small and have a stigma situated at the same level as the apex of the anthers whereas on the east coast, flowers are larger and have the stigma below the anthers. On Sardinia, A. crispa subsp. crispa has a floral morphology similar to the Corsican plants, whereas subspecies maritima has larger flowers with the stigma positioned above the anthers (approach-herkogamy). Quantitative variation in floral morphology thus agrees with the separation of two taxonomic entities on Sardinia and geographic variation in reproductive traits and isozymes has important ramifications for the sampling of populations for conservation programmes. 相似文献
18.
Dickey C.C. Lau Clement P. Dumont Gilbert C.S. Lui Jian-Wen Qiu 《Biological conservation》2011,144(11):2674-2683
Assessment of the effectiveness of protected areas requires information on population characteristics of the target species. This study used a mark-and-recapture approach to examine the population structure, individual growth, and mortality of the commercially harvested short-spined sea urchin Anthocidaris crassispina in a small (18 ha) no-take marine reserve and two nearby non-protected sites. Sea urchins were tagged with fluorochrome and recaptured 1 year later. The size-at-age relationship was modelled using the Tanaka function, and mortality estimated using an exponential decay function coupled with the Tanaka growth parameters. The urchin population in the reserve consisted of a higher proportion of older individuals than populations in the two non-protected areas, however, large sea urchins (>50 mm) were absent in the reserve. Sea urchins occurring at high densities (>15 ind. m−2) in the reserve grew much slower than those outside the reserve, suggesting a density-dependant effect on growth. Growth ring analysis from the rotulae supported the mark-and-recapture results with the maximum number of rings being higher in the reserve than in non-protected sites. Urchins with the same number of growth rings inside the reserve were smaller than those outside the reserve. Within the reserve, urchins with the same number of growth rings were smaller at locations with higher urchin density. Annual mortality rate was lower in the reserve population than in the non-protected populations. These results illustrate the effectiveness of this small reserve in protecting A. crassispina from fishing. However, further study is required to examine whether a high density of small/old individuals is better than a medium density of large individuals in order to maximize the potential spillover of larvae by such small urchin refugia to the surrounding overfished areas. 相似文献
19.
It is becoming increasingly difficult to manage and expand statutory conservation areas (i.e., parks and formally protected areas). Therefore, alternative opportunities for land conservation merit closer attention. This paper examines the extent to which privately owned conservation areas contribute to biodiversity representation. Gap analyses were performed for a large semi-arid region in South Africa with a comprehensive database of private conservation areas. The distribution of private conservation areas was compared to statutory conservation areas using several landscape characteristics: biome and vegetation variant, elevation class, ecological process area, total area, and threat status (endangerment). Conservation target achievement for the vegetation variants was also assessed, as was the degree to which private conservation areas complemented statutory conservation areas by representing different landscape characteristics. The number of targets achieved nearly tripled if private conservation areas were considered in addition to statutory conservation areas. Further, private conservation areas significantly complemented statutory conservation areas in the types of biomes, elevation classes, and threat status classes conserved. Private conservation areas were especially important in conserving lower elevation habitat, and by association, endangered vegetation. This particular relationship is expected to be common worldwide. Our results indicate that private lands conservation deserves an increased allocation of resources for both research and implementation. 相似文献
20.
M. E. Lucas‐Borja F. Bastida J. L. Moreno C. Nicols M. Andres F. R. Lpez A. Del Cerro 《Land Degradation \u0026amp; Development》2011,22(4):383-394
Increased tourist activity and recreational use of wilderness and other protected areas has endangered zones of high environmental value. The aim of this work was to evaluate the effects of trampling intensity (low, high use trails and untrampled trails) and distance from the trails (on the trails, at 10 and 20 m from the trails) on the vegetation, chemical, physical and microbiological properties of a soil in Mediterranean mountain areas. Trail type and distance from the trail significantly influenced several parameters. High use trails showed lower values of plant cover and diversity of vegetation species, as well as soil respiration and some enzyme activities (phosphatase, β‐glucosidase and dehydrogenase) than low use trails. In addition, the effects of trampling spatially extended further from these high use trails than from low use trails. Statistical analysis showed that some microbiological (basal respiration, dehydrogenase activity and β‐glucosidase activity) and vegetal parameters (plant cover and diversity) may be established as a set of indicators for the evaluation of soil quality on these areas subjected to human trampling. We concluded that trampling significantly impacts on soil microbial processes and vegetal communities, and visitor should be restricted from entering ecologically sensitive areas due to the effects of trampling. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献