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821.
As the number of marine protected areas (MPAs) is globally increasing, information is needed on the effectiveness of existing
sites. Many protected area agencies however have limited resources and are unable to evaluate MPA effectiveness. An evaluation
conducted entirely by the managing agency may also lack credibility. Long-term monitoring and evaluation programs should ideally
offer opportunities for participation of diverse groups in the selection of evaluation indicators and their assessment. A
participatory approach has the potential to enhance evaluation capacity, to increase credibility and acceptance of results,
to strengthen relationships between managers and local stakeholders, and to address more locally relevant information. Using
a case study approach, this paper investigates diverse stakeholder groups’ opinions on the design of an evaluation and their
interest to participate in an assessment. Respondents were most interested in the assessment of MPA achievements and outcome
indicators. Most groups identified a range of government agencies and stakeholders that should participate in an assessment
but only half of all respondents were interested to participate in monitoring activities. Most frequently mentioned limitations
for more participation were a lack of time and money, but also governance shortcomings such as limited participation possibilities
and not paying enough credit to stakeholders’ input. Participation interest was also influenced by occupation, place of residency,
and familiarity with the marine environment. Differences exist among stakeholders about suitable evaluators and preferred
monitoring partners, which could affect the credibility of evaluation results and affect monitoring activities. 相似文献
822.
Merle Sowman Maria Hauck Lance van Sittert Jackie Sunde 《Environmental management》2011,47(4):573-583
A historical perspective on MPA identification and governance in South Africa reflects the continued influence of a top-down
and natural science-based paradigm, that has hardly changed over the past half century, despite the wealth of literature,
and a growing consensus, that advocates the need to adopt a more integrated and human-centered approach. Based on extensive
research in two coastal fishing communities, the paper highlights impacts and conflicts arising from this conventional approach
to MPA identification, planning and management. It argues that failure to understand the particular fishery system in all
its complexity, in particular the human dimensions, and involve resource users in planning and decision-making processes,
undermines efforts to achieve conservation and fisheries management objectives. The customary rights of local resource users,
and their food and livelihood needs in relation to marine resources, need to be acknowledged, prioritized and integrated into
planning and decision-making processes. Convincing ecologists, fisheries scientists and managers, that MPA success depends
on addressing the root causes of resource decline and incorporating social factors into MPA identification, planning and management,
remains a huge challenge in South Africa. 相似文献
823.
Many alpine ski areas have recently adopted voluntary environmental programs (VEPs) such as using recycling, renewable energy,
and biofuels to help reduce their environmental impacts. Studies have addressed the performance of these VEPs in mitigating
environmental impacts of this industry, but little is known about visitor awareness and perceptions of these programs. This
article addresses this knowledge gap by exploring skier and snowboarder knowledge of VEPs at a ski area and the influence
of these programs on their motivations to visit this area currently and behavioral intentions to visit again in the future.
Data were obtained from an onsite survey at the Mt. Bachelor ski area in Oregon, USA (n = 429, 89.7% response rate). Few skiers and snowboarders were knowledgeable of VEPs at this area and fewer than 20% were
motivated to visit on their current trip because of these programs. Other attributes such as scenery, snow conditions, and
access were more important for influencing visitation. Up to 38% of skiers and snowboarders, however, intend to visit this
ski area more often if it adopts and promotes more VEPs. Managers can use these results to inform communication and marketing
of their environmental programs and performance to visitors. Additional implications for management and future research are
discussed. 相似文献
824.
Mohammad Aslam Khan S. Akhtar Ali Shah 《Journal of Agricultural and Environmental Ethics》2011,24(5):493-509
There is evidence of continued food insecurity and malnutrition in Pakistan despite significant progress made in terms of
food production in recent years. According to “Vision 2030” of the Planning Commission of Pakistan, about half of the population
in the country suffers from absolute to moderate malnutrition, with the most vulnerable being children, women, and elderly
among the lowest income group. The Government of Pakistan has been taking a series of policy initiatives and strategic measures
to combat food insecurity issues. These range from increasing production to food imports, implementation of poverty reduction
strategies, nutritional improvement programs, as well as provision of social safety nets. The article aims to instill some
fresh thinking into the debate regarding the challenges of food security. It underscores the limitations of hitherto policy
response, and suggests crucial measures to improve the present grim scenario. Policy makers, planners, practitioners, and
academicians in countries with comparable socio-political and economic setup can view this discussion as a case study and
may apply the findings in their domain accordingly. 相似文献
825.
Congruence Among Encounters,Norms, Crowding,and Management in a Marine Protected Area 总被引:1,自引:0,他引:1
Over the past few decades, recreation and tourism use has increased at many marine protected areas, generating concerns about
impacts of this increasing use on experiences and conditions at these areas (e.g., crowding, conflict). This article uses
data from Molokini Shoal Marine Life Conservation District in Hawai’i to examine: (a) reported encounters, crowding, normative
tolerances for various use levels, and support of use related management strategies at this site; and (b) whether users who
encounter higher use levels than their norms feel more crowded and are more supportive of restrictive management strategies.
Data were obtained from onsite pre-trip and post-trip questionnaires of 712 passengers on commercial snorkel and dive tours
visiting this site. Norms were measured with acceptance of 12 photographs depicting levels of boat use. On average, users
would accept seeing no more than approximately 16 boats at one time at Molokini and this number was observed on over 20% of
trips to the site. Although the majority of users expected to escape crowds at Molokini, 67% felt crowded and up to 79% supported
actions that would directly restrict use at this site (e.g., limit number of boats). Users who encountered more boats than
their normative tolerance felt more crowded and were more supportive of these management strategies. Findings suggest that
this marine protected area is operating over its capacity and management is needed to improve experiences and conditions. 相似文献
826.
Private domestic gardens contribute substantially to the biodiversity of urban areas and benefit human health and well-being.
We previously reported a study of 267 gardens across five cities in the United Kingdom in which variation in geographical
and climatic factors had little bearing on the richness, diversity and composition of plant species. We therefore hypothesise
that garden management is an important factor in determining garden characteristics. Here, from the same sample of gardens,
we investigate potential associations between the uses to which people put their gardens, the types of management activities
they undertake, and the characteristics of those gardens. Householders (n = 265) completed a questionnaire detailing various aspects of garden use and management activities. The majority of respondents
used their gardens chiefly for relaxation, recreation, and eating. Fewer than one fifth included “gardening” amongst their
garden uses even though all performed some garden management, suggesting that not all management activity resulted from an
interest in gardening. Garden-watering and lawn-mowing were the most prevalent activities and were predictors of other types
of management including weeding, vegetation-cutting, leaf-collection, and dead-heading flowers. A number of these activities
were associated with one another, the richness and composition of plant species, and the number of land uses in gardens. However,
relationships between management activities and the amount of tall vegetation were less consistent, and garden management
appeared to be independent of garden area. More species of amphibians, birds, and mammals were observed in gardens with ponds
and in which efforts were made to attract wildlife, particularly by providing drinking water. This study supports the hypothesis
that garden use and management is associated with garden characteristics. 相似文献
827.
We investigated the type and extent of degradation at three sites on the Agulhas Plain, South Africa: an old field dominated
by the alien grass Pennisetum clandestinum Pers. (kikuyu), an abandoned Eucalyptus plantation, and a natural fynbos community invaded by nitrogen fixing—Australian Acacia species. These forms of degradation are representative of many areas in the region. By identifying the nature and degree
of ecosystem degradation we aimed to determine appropriate strategies for restoration in this biodiversity hotspot. Vegetation
surveys were conducted at degraded sites and carefully selected reference sites. Soil-stored propagule seed banks and macro-
and micro-soil nutrients were determined. Species richness, diversity and native cover under Eucalyptus were extremely low compared to the reference site and alterations of the soil nutrients were the most severe. The cover of
indigenous species under Acacia did not differ significantly from that in reference sites, but species richness was lower under Acacia and soils were considerably enriched. Native species richness was much lower in the kikuyu site, but soil nutrient status
was similar to the reference site. Removal of the alien species alone may be sufficient to re-initiate ecosystem recovery
at the kikuyu site, whereas active restoration is required to restore functioning ecosystems dominated by native species in
the Acacia thicket and the Eucalyptus plantation. To restore native plant communities we suggest burning, mulching with sawdust and sowing of native species. 相似文献
828.
Gabi N. Waite Stéphane J. P. Egot-Lemaire Walter X. Balcavage 《The Environmentalist》2011,31(2):107-113
Over the past decades, strong evidence has accumulated that low-frequency electromagnetic fields (EMFs) can be useful in treating
human pathologies, such as bone fractures, soft tissue illnesses, and pain. Common strategies for the design of commercial
therapeutic devices are to generate EMFs that simulate body endogenous EMFs, or EMFs that resonate with a particular biological
process, such as the natural motions of ions. We recently came across a biologically active commercial EMF signal that seems
to be different. The signal is generated by summing the fundamental frequencies and harmonics of several periodic base signals
which remain proprietary to the company. When first examined in the time domain, the signal resembled electronic noise; however,
when critically analyzed, the signal is not identical with noise. Rather, it is a highly complex waveform exhibiting a very
wide range of values for the time derivative of the magnetic field density (dB/dt) and a beat frequency in the Extremely Low-Frequency
range. In this paper, we speculate on the mechanism of action of this and similar signals. We consider it less likely that
cells, or cell components, act like filters to extract and couple with individual signals that make up the complex EMF signal.
Consequently, we favor the possibility that with the signal discussed here cells respond to the very complex signal and that
the biological response can be modified by the presence of a beat in the signal, in this case a low-frequency beat. More generally,
this would suggest the hypothesis that biological processes can be regulated by noise-like signals and that the effects of
a noisy signal can be modified by the presence of signal repetition patterns, such as beats. Given the very small energy that
signals like these can transduce into a biological system, biological effects can be expected only when the molecular processes
involved are poised so that the available energy leads to molecular reactions that achieve the activation state for the reaction. 相似文献
829.
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
830.
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