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991.
Throughout the world there is a general consensus among environmentalists that there should be an increase in the amount of
marine area that should be reserved in marine protected areas (MPAs). In fact, the 1998 Philippines Fishery Code indicates
a need for designation of at least 15% of municipal waters for fish refuges or sanctuaries. Such an increase in area would
take productive fishing areas away from fishing communities that can ill-afford the loss. The larger the protected area, there
will be a greater number of people impacted. This article examines the relationship between factors that influence the success
of Community Based MPA (CBMPA) performance in the Visayas, Philippines and their significance in efforts to increase the size
of protected areas. 相似文献
992.
Cetacean-focused tourism in Taiwan has grown rapidly since 1997. This development, measured in terms of both number of tour
boats and visitors, has resulted in many resource management challenges stemming from the absence of regulation and scientific
data. To fill this void in empirical evidence, we used 464 sighting records from 2002 to 2005 to model the impact of cetacean-focused
tourism. Cox proportional hazard analysis indicated cetacean avoidance responses to cetacean watching boats were strongly
associated with pod size, mother–calf pairs, and cetacean-vessel distances. Mother–calf pairs abandoned their avoidance tactic
by 55% compared to noncalf groups when tour boats approached. Second, the hazard ratio of abundance was 0.996, suggesting
that the odds of encountering avoidance responses by the cetaceans decreased by 42% for every 100-member increase in the cetacean
pod size. Last, distances maintained by boats from the cetaceans was positively related to avoidance responses (i.e., less
avoidance behavior with closer interaction). Based on our findings, we have the following recommendations: (a) limit vessels
from approaching mothers with calves, (b) limit vessels from approaching small groups of cetaceans, (c) reduced avoidance
behavior to boat traffic may be a red flag for potential long-term disturbance, and (d) apply the “precautionary principle”
based on the best scientific information available in cetacean-based tourism in Taiwan. These recommendations will help contribute
to the sustainable development of cetacean-focused tourism in Taiwan. 相似文献
993.
This article examines one MPA—the Gulf of Mannar National Park and Biosphere Reserve—located in southern India, and four types
of social conflict that have surrounded its establishment. Taking the strength of wellbeing aspirations as point of departure,
we focus on two themes: the implications of MPA embeddedness in wider societal systems, and the consequences of natural and
social variety for governance. We conclude first of all that conflict resolution depends on MPA authorities’ willingness to
engage with the interferences that emerge from outside the MPA area. Secondly, we point out the varying wellbeing aspirations
of the population and the need to develop governance partnerships. The latter are argued to contribute to more balanced decision
making, as well as to a greater appreciation among the target population of the ‘fairness’ of MPA policy. 相似文献
994.
Marine Protected Dramas: The Flaws of the Brazilian National System of Marine Protected Areas 总被引:1,自引:0,他引:1
Leopoldo C. Gerhardinger Eduardo A. S. Godoy Peter J. S. Jones Gilberto Sales Beatrice P. Ferreira 《Environmental management》2011,47(4):630-643
This article discusses the current problems and issues associated with the implementation of a National System of Marine Protected
Areas in Brazil. MPA managers and higher governmental level authorities were interviewed about their perceptions of the implementation
of a national MPA strategy and the recent changes in the institutional arrangement of government marine conservation agencies.
Interviewees’ narratives were generally pessimistic and the National System was perceived as weak, with few recognizable marine
conservation outcomes on the ground. The following major flaws were identified: poor inter-institutional coordination of coastal
and ocean governance; institutional crisis faced by the national government marine conservation agency; poor management within
individual MPAs; problems with regional networks of marine protected areas; an overly bureaucratic management and administrative
system; financial shortages creating structural problems and a disconnect between MPA policy and its delivery. Furthermore,
a lack of professional motivation and a pessimistic atmosphere was encountered during many interviews, a malaise which we
believe affects how the entire system is able to respond to crises. Our findings highlight the need for a better understanding
of the role of ‘leadership’ in the performance of socio-ecological systems (such as MPA networks), more effective official
evaluation mechanisms, more localized audits of (and reforms if necessary to) Brazil’s federal biodiversity conservation agency
(ICMBio), and the need for political measures to promote state leadership and support. Continuing to focus on the designation
of more MPAs whilst not fully addressing these issues will achieve little beyond fulfilling, on paper, Brazil’s international
marine biodiversity commitments. 相似文献
995.
The Fate of Priority Areas for Conservation in Protected Areas: A Fine-Scale Markov Chain Approach 总被引:1,自引:0,他引:1
Park managers in alpine areas must deal with the increase in forest coverage that has been observed in most European mountain
areas, where traditional farming and agricultural practices have been abandoned. The aim of this study is to develop a fine-scale
model of a broad area to support the managers of Paneveggio Nature Park (Italy) in conservation planning by focusing on the
fate of priority areas for conservation in the next 50–100 years. GIS analyses were performed to assess the afforestation
dynamic over time using two historical maps (from 1859 and 1936) and a series of aerial photographs and ortho-photos (taken
from 1954 to 2006) covering a time span of 150 years. The results show an increase in the forest surface area of about 35%.
Additionally, the forest became progressively more compact and less fragmented, with a consequent loss of ecotones and open
habitats that are important for biodiversity. Markov chain-cellular automata models were used to project future changes, evaluating
the effects on a habitat scale. Simulations show that some habitats defined as priority by the EU Habitat Directive will be
compromised by the forest expansion by 2050 and suffer a consistent loss by 2100. This protocol, applied to other areas, can
be used for designing long-term management measures with a focus on habitats where conservation status is at risk. 相似文献
996.
Rosenfeld J Hogan D Palm D Lundquist H Nilsson C Beechie TJ 《Environmental management》2011,47(1):28-39
Sediment size and supply exert a dominant control on channel structure. We review the role of sediment supply in channel structure,
and how regional differences in sediment supply and landuse affect stream restoration priorities. We show how stream restoration
goals are best understood within a common fluvial geomorphology framework defined by sediment supply, storage, and transport.
Landuse impacts in geologically young landscapes with high sediment yields (e.g., coastal British Columbia) typically result
in loss of instream wood and accelerated sediment inputs from bank erosion, logging roads, hillslopes and gullies. In contrast,
northern Sweden and Finland are landscapes with naturally low sediment yields caused by low relief, resistant bedrock, and
abundant mainstem lakes that act as sediment traps. Landuse impacts involved extensive channel narrowing, removal of obstructions,
and bank armouring with boulders to facilitate timber floating, thereby reducing sediment supply from bank erosion while increasing
export through higher channel velocities. These contrasting landuse impacts have pushed stream channels in opposite directions
(aggradation versus degradation) within a phase-space defined by sediment transport and supply. Restoration in coastal British
Columbia has focused on reducing sediment supply (through bank and hillslope stabilization) and restoring wood inputs. In
contrast, restoration in northern Fennoscandia (Sweden and Finland) has focused on channel widening and removal of bank-armouring
boulders to increase sediment supply and retention. These contrasting restoration priorities illustrate the consequences of
divergent regional landuse impacts on sediment supply, and the utility of planning restoration activities within a mechanistic
sediment supply-transport framework. 相似文献
997.
In this article, we introduce China’s major forest types and discuss the historical development of forest management in China,
including actions taken over the last decade toward achieving SMF. Major challenges are identified, and a strategy for SFM
implementation in China is presented. China’s forests consist of a wide variety of types with distinctive distributional patterns
shaped by complex topography and multiple climate regimes. How to manage this wide array of forest resources has challenged
forest managers and policy-makers since the founding of the country. Excessive exploitation of China's forest resources from
the 1950s to the late 1990s contributed to environmental problems and calamities, such as floods, soil erosion, and desertification.
At the start of the new millennium, the Chinese government decided to shift its emphasis from timber production towards the
achievement of sustainable forest management (SFM). With a series of endeavors such as the implementation of the “Six Key
Forestry Projects” and the reform of forest tenure policies, and the adoption of a classification system for China's forests,
a beginning has been made at reversing the trend of environmental degradation that occurred throughout the latter half of
the last century. At the same time, huge challenges remain to be tackled for the development of forestry in China. 相似文献
998.
Lemons J 《Environmental management》2011,48(3):379-391
I review the status of scientific, political, and moral problems of global climate change (GCC) and, based on lessons from
environmental and sustainability programs in universities, demonstrate that universities have had a lethargic response to
urgent needs to mitigate the problems. I explore reasons for the response, and conclude that there is an urgent need for comprehensive
and wide–ranging change in universities to help mitigate GCC. My discussion is focused on those within universities as well
as those in environmental professions regardless of their areas of specialization. 相似文献
999.
We demonstrate the use of an expert-assisted spatial model to examine geographic factors influencing the poaching risk of
a rare plant (American ginseng, Panax quinquefolius L.) in Shenandoah National Park, Virginia, USA. Following principles of the analytic hierarchy process (AHP), we identified
a hierarchy of 11 geographic factors deemed important to poaching risk and requested law enforcement personnel of the National
Park Service to rank those factors in a series of pair-wise comparisons. We used those comparisons to determine statistical
weightings of each factor and combined them into a spatial model predicting poaching risk. We tested the model using 69 locations
of previous poaching incidents recorded by law enforcement personnel. These locations occurred more frequently in areas predicted
by the model to have a higher risk of poaching than random locations. The results of our study can be used to evaluate resource
protection strategies and to target law enforcement activities. 相似文献
1000.
Measuring the Social Recreation Per-Day Net Benefit of the Wildlife Amenities of a National Park: A Count-Data Travel-Cost Approach 总被引:2,自引:0,他引:2
In this article, we apply count-data travel-cost methods to a truncated sample of visitors to estimate the Peneda-Gerês National
Park (PGNP) average consumer surplus (CS) for each day of visit. The measurement of recreation demand is highly specific because
it is calculated by number of days of stay per visit. We therefore propose the application of altered truncated count-data
models or truncated count-data models on grouped data to estimate a single, on-site individual recreation demand function,
with the price (cost) of each recreation day per trip equal to out-of-pocket and time travel plus out-of-pocket and on-site
time costs. We further check the sensitivity of coefficient estimations to alternative models and analyse the welfare measure
precision by using the delta and simulation methods by Creel and Loomis. With simulated limits, CS is estimated to be €194
(range €116 to €448). This information is of use in the quest to improve government policy and PNPG management and conservation
as well as promote nature-based tourism. To our knowledge, this is the first attempt to measure the average recreation net
benefits of each day of stay generated by a national park by using truncated altered and truncated grouped count-data travel-cost
models based on observing the individual number of days of stay. 相似文献