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Andrés M Cisneros-Montemayor Amanda Townsel Claire M Gonzales Andrea R Haas Estrella E Navarro-Holm Teresa Salorio-Zuñiga Andrew F Johnson 《Natural resources forum》2020,44(2):111-128
Ecotourism can incentivize social and environmental benefits through marine conservation, in parallel with efforts to better manage fisheries, coastal development, and other human pressures. In Mexico's Gulf of California and Baja California Peninsula (GCBP), marine ecosystems support tourism activities in many communities, but to date there have been no region-wide studies to estimate their benefits or identify key species. Based on data collected in this study, each year nature-based marine tourism in the GCBP results in 896,000 visits, US$518 million in expenditures and at least 3,575 direct jobs from formal operations. In interviews with operators, over 40 species groups were named as important; sea lions, whale sharks, whales, and marlin were the highest ranked, highlighting the importance of ecosystem-wide health for nature-based tourism sustainability. Local employment and the ability to make economic and conservation goals compatible were noted by operators as significant opportunities provided by nature-based marine tourism; challenges included pollution and declines in ecosystem health, a lack of infrastructure, poor resource management policies, and high operating costs. As nature-based marine tourism expands, a wider transition to true ecotourism, a focus on equitable benefits and collaboration between stakeholders and a cross-scale and ecosystem approach to management will be vital for achieving potential sustainable social, ecological and economic benefits. 相似文献
233.
Human activities can alter selective environments in ways that can reduce the usefulness of certain ornamental traits as honest signals of individual quality and, in some cases, may create evolutionary traps, where rapid changes in selective environments result in maladaptive behavioral decisions. Using the sexually dichromatic, socially monogamous Northern Cardinal (Cardinalis cardinalis) as a model, we hypothesized that urbanization would erode the relationship between plumage coloration and reproductive success. Because the exotic Amur honeysuckle (Lonicera maackii) provides carotenoids, is a preferred habitat attribute, and increases vulnerability to nest predation, we predicted the presence of an evolutionary trap, whereby the brightest males would achieve the lowest reproductive success. Working at 14 forests in Ohio, USA, 2006-2008, we measured plumage color, monitored reproduction, and quantified habitat within territories. In rural landscapes, the brightest males bred earliest in the season and secured more preferred territories; however, annual reproduction declined with plumage brightness. Coloration of urban males was not associated with territory attributes or reproduction. Female redness across all landscapes was negatively related to reproduction. Poor reproductive performance of otherwise higher-quality males probably resulted from preferences for honeysuckle, which reduces annual reproduction when used as a nesting substrate early in the season. In this way, exotic shrubs prompted an evolutionary trap that was avoided in urban forests where anthropogenic resources disassociated male color and reproductive phenology and success. Our study illustrates how modified selective environments in human-dominated landscapes might shape microevolutionary processes in wild bird populations. 相似文献
234.
Chosen goals influence the outcomes a person achieves as well as the behaviors performed to achieve those outcomes. In this study, we propose that three forms of goal orientation: learning, performance‐prove, and performance‐avoid, (VandeWalle, 1997 ) relate to performance, with learning and performance‐prove relating to performance through regulatory foci of prevention and promotion, respectively. Regulatory focus, a type of self‐regulation, entails the implementation of specific strategies in pursuit of goals and thus gives us insight to how a person pursues a chosen goal. In a combination of laboratory and field studies, we examine the role of regulatory focus as a mediator between goal orientation and task performance. We find evidence that regulatory focus strategies differentially mediate the goal orientation/task performance relationship. Theoretical ramifications for these relationships, as well as practical implications, are discussed. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
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Wrasses are abundant reef fishes and the second most speciose marine fish family, yet little is known of their larval swimming
abilities. In August 2010 at Moorea, Society Islands, we measured swimming ability (critical speed, Ucrit) of 80 settlement-stage
larvae (11–17 mm) of 5 labrid species (Thalassoma quinquevittatum [n = 67], Novaculichthys taeniourus [n = 6], Coris aygula [n = 5], Halichoeres trimaculatus [n = 1] and H. hortulanus [n = 1]) and 33 new recruits of T. quinquevittatum. Median (mdn) larval Ucrit was 7.6–12.5 cm s−1. In T. quinquevittatum (n = 67), larvae of 12.5–14.5 mm swam faster (mdn 16.9 cm s−1) than smaller or larger larvae (mdn 3.9 and 3.2 cm s−1, respectively). Labrid larvae Ucrit is similar to that of other similar-sized tropical larvae, so labrids and species with
comparable settlement sizes should have similar abilities to influence dispersal. Ucrit of T. quinquevittatum recruits decreased to 47–56% of larval Ucrit in 2 days, implying rapid physiological changes at settlement. 相似文献
237.
Marivic G. Pajaro Monica E. Mulrennan Amanda C. J. Vincent 《Environment, Development and Sustainability》2010,12(6):945-965
Policy development related to marine protected areas (MPAs) occurs at three levels: international, national, and local. Recent
developments with MPAs highlight their close links to broader national-level park and protected area policies, which in turn
take their lead from initiatives and recommendations initiated, and increasingly dictated, by international organizations.
Local-level inputs to MPA policies have tended to be limited to the immediate local area context despite the vital importance
of community-level support and knowledge in meeting broader regional goals of marine conservation tied to networked MPAs.
In this paper, we highlight the mechanisms to facilitate cooperation and communication among international, national, and
local levels of policy and practice needed to address this deficit. These include the creation of a social network of institutions
that both internationalizes and localizes MPA policy development, facilitating a more meaningful engagement of local people
through their legitimate participation in national and international MPA gatherings. In addition, mechanisms to formalize
partnerships, feedback information, resolve conflicts, and report accountabilities are needed. The success of the latter will
depend on the level of recognition and support given to community-level institutions as opposed to the suite of technical
training and short-term project-based interventions that have characterized local support over recent decades. 相似文献
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239.
Amanda C. Lima Sergio N. Monteiro Kestur G. Satyanarayana 《Journal of Polymers and the Environment》2012,20(1):245-253
In recent times, environmental safety has been on priority in the development of new materials leading to a recycling and
reuse approach to conserve the materials resources. This has resulted in more focus on the application of natural materials
such as lignocellulosic fibers. This paper presents the characterization of continuous and aligned jute fabrics obtained from
new and used sacks as well as the preparation and characterization of their composites incorporated into recycled polyethylene
or as isolated pieces up to 40 wt%. These environmentally friendly composites were subjected to bend test and the fracture
surface analyzed by SEM. The fabric from new sacks showed greater damage tolerance than that from the used sacks. The flexural
stress increased steadily with increasing used fabric content up to 30 wt%, which is explained using fractographic studies
on ruptured specimens. Used jute fabric composites are found to be viable alternative materials for low strength conventional
materials based on cost–performance comparison with conventional materials. 相似文献
240.