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181.
Regional Environmental Change - Sea level is projected to rise over the coming decades, further increasing the extent of flooding hazards in coastal communities. Efforts to address potential...  相似文献   
182.
Species that cannot adapt or keep pace with a changing climate are likely to need human intervention to shift to more suitable climates. While hundreds of articles mention using translocation as a climate-change adaptation tool, in practice, assisted migration as a conservation action remains rare, especially for animals. This is likely due to concern over introducing species to places where they may become invasive. However, there are other barriers to consider, such as time-frame mismatch, sociopolitical, knowledge and uncertainty barriers to conservationists adopting assisted migration as a go-to strategy. We recommend the following to advance assisted migration as a conservation tool: attempt assisted migrations at small scales, translocate species with little invasion risk, adopt robust monitoring protocols that trigger an active response, and promote political and public support.  相似文献   
183.
In 1995 the provincial government of British Columbia, Canada, passed new legislation encouraging regional districts to prepare Regional Growth Strategies. The strategies were to be means of coordinating municipal action on regional issues. They were also meant to facilitate pursuit of sustainability objectives, including reducing urban sprawl, protecting environmentally sensitive areas, providing affordable housing and decreasing pollution. This paper examines the experience so far in one region that chose to prepare a growth strategy: the Capital Regional District (CRD) at the south end of Vancouver Island. Growth‐management planning in the CRD has been and remains both critical and difficult. The region expects a substantial population increase over the next couple of decades and has a limited land base for urban expansion. Many citizens recognise that their quality of life is high, but vulnerable and, as a result, public support for effective growth management is stronger in the CRD than in many other provincial growth areas. However, BC does not have a tradition of strong regional governance and the CRD as a regional authority is the creature of sixteen municipalities and electoral areas. Seven years into the process, effective growth management still faces substantial challenges, including the persistent jurisdictional protectionism of CRD municipalities. Nevertheless, there have been positive achievements and an admirable diversity of individuals, organisations and initiatives continue to push municipal and regional officials towards a more sustainable future.  相似文献   
184.
The use of pesticides to increase agricultural production can result in the contamination of the environment, causing changes in the genetic structure of organisms and in the loss of biodiversity. This practice is also inducing changes in the rainforest ecosystem. In this work, a Pseudomonas aeruginosa isolated from a preservation soil area of the Brazilian Amazon Forest, without usage of any pesticide, was evaluated for its potential to degrade atrazine. This isolate presented all responsible genes (atzA, atzB, atzC, atzD, atzE, and atzF) for atrazine mineralization and demonstrated capacity to use atrazine as a nitrogen source, having achieved a reduction of 44 % of the initial concentration of atrazine after 24 h. These results confirm gene dispersion and/or a possible contamination of the area with the herbicide, which reinforces global concern of the increase and intensive use of pesticides worldwide.  相似文献   
185.
The influence of individual differences and negotiation strategies on starting salary outcomes was investigated. A sample of 149 newly hired employees in various industry settings participated in this study. Results indicated that those who chose to negotiate increased their starting salaries by an average of $5000. Individuals who negotiated by using competing and collaborating strategies, characterized by an open discussion of one's positions, issues, and perspectives, further increased their salaries as compared to those who used compromising and accommodating strategies. Individual differences, including risk‐aversion and integrative attitudes, played a significant role in predicting whether or not individuals negotiated, and if so, what strategies they used. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
186.
Zoos and aquariums are increasingly incorporating conservation education into their mission statements and visitor experiences to address global biodiversity loss. To advance knowledge and practice in the field, research is being conducted to evaluate the effect of zoo conservation-education experiences on visitor psychosocial outcomes (e.g., knowledge, attitude, emotions, motivations, behavior). Following recent discussions among scholars and practitioners concerning logistical and methodological challenges that likely undermine the conclusions of such research, we identified and reviewed the methods and reporting practices in peer-reviewed articles published in English from May 1998 to June 2016 that focused on adult visitor samples (47 articles, 48 studies). We examined elements of internal, external, construct, and statistical conclusion validity. Methodological quality of quantitative methods and reporting practices was determined using the Effective Public Health Practice Project Quality Assessment Tool. Each study was coded as either strong (no weak ratings), moderate (1 weak rating), or weak (≥2 weak ratings). The quantitative methods of 83.3% of studies were weak. The remaining 16.7% had methods of moderate quality. Using an existing checklist, we also assessed the quality and rigor of qualitative methods and reporting practices and found that some aspects of these methods were reported more comprehensively than others. For example, 69.6% of articles discussed methods for identifying key themes from the data, whereas only 34.8% reported how data verification was performed. We suggest increased application of intensive longitudinal methods (e.g., daily diary) to strengthen self-reported data, experimental and repeated-measures designs, and mixed-methods approaches. Our findings and recommendations could strengthen and guide the research and evaluation agenda for the field and ultimately enhance the contribution zoos make to global biodiversity conservation.  相似文献   
187.
We used acoustic telemetry to examine the small-scale movement patterns of yellowfin tuna (Thunnus albacares) in the California Bight at the northern extent of their range. Oceanographic profiles of temperature, oxygen, currents and fluorometry were used to determine the relationship between movements and environmental features. Three yellowfin tuna (8 to 16 kg) were tracked for 2 to 3 d. All three fish spent the majority of their time above the thermocline (18 to 45 m in depth) in water temperatures >17.5 °C. In the California Bight, yellowfin tuna have a limited vertical distribution due to the restriction imposed by temperature. The three fish made periodic short dives below the thermocline (60 to 80 m), encountering cooler temperatures (>11 °C). When swimming in northern latitudes, the depth of the mixed layer largely defines the spatial distribution of yellowfin tuna within the water column. Yellowfin prefer to spend most of their time just above the top of the thermocline. Oxygen profiles indicated that the tunas encountered oceanic water masses that ranged most often from 6.8 to 8.6 mg O2 l−1, indicating no limitation due to oxygen concentrations. The yellowfin tuna traveled at speeds ranging from 0.46 to 0.90 m s−1 (0.9 to 1.8 knots h−1) and frequently exhibited an oscillatory diving pattern previously suggested to be a possible strategy for conserving energy during swimming. Received: 14 February 1997 / Accepted: 14 April 1997  相似文献   
188.
Informal recycling networks are systems through which impoverished populations earn money and residents recycle waste which might otherwise go into a landfill. These networks, in which people voluntarily self-organise to collect recyclables, occur throughout the world. This article discusses results of an exploratory, qualitative study of one such network in St. John's, Newfoundland and Labrador which identifies motivational characteristics of the network and their implications for public policy. Through close attention to particularities of place, the research identified community interaction and community inclusion as two of the most active motivating factors within the studied network. The findings suggest public recycling programmes can increase public participation through greater attention to place-based motivational factors. Such participation could contribute to increased sustainability and reach of recycling programmes.  相似文献   
189.
Over 180 non‐native species have been introduced in the Laurentian Great Lakes region, many posing threats to native species and ecosystem functioning. One potential pathway for introductions is the commercial bait trade; unknowing or unconcerned anglers commonly release unused bait into aquatic systems. Previous surveillance efforts of this pathway relied on visual inspection of bait stocks in retail shops, which can be time and cost prohibitive and requires a trained individual that can rapidly and accurately identify cryptic species. Environmental DNA (eDNA) surveillance, a molecular tool that has been used for surveillance in aquatic environments, can be used to efficiently detect species at low abundances. We collected and analyzed 576 eDNA samples from 525 retail bait shops throughout the Laurentian Great Lake states. We used eDNA techniques to screen samples for multiple aquatic invasive species (AIS) that could be transported in the bait trade, including bighead (Hypophthalmichthys nobilis) and silver carp (H. molitrix), round goby (Neogobius melanostomus), tubenose goby (Proterorhinus marmoratus), Eurasian rudd (Scardinius erythrophthalmus), and goldfish (Carassius auratus). Twenty‐seven samples were positive for at least one target species (4.7% of samples), and all target species were found at least once, except bighead carp. Despite current regulations, the bait trade remains a potential pathway for invasive species introductions in the Great Lakes region. Alterations to existing management strategies regarding the collection, transportation, and use of live bait are warranted, including new and updated regulations, to prevent future introductions of invasive species in the Great Lakes via the bait trade. El Uso del ADN Ambiental en la Vigilancia de Especies Invasoras del Mercado de Carnada Comercial de los Grandes Lagos  相似文献   
190.
Many common pool resources have traditionally been managed through intricate local governance arrangements. Over time, such arrangements are confronted with manifold political, social, economic and ecological changes. However, the ways in which local governance arrangements react to such changes are poorly understood. Using the theoretical concept of institutional adaptation, we analyse the history of Harenna forest, Ethiopia, to examine processes of institutional change over the last 150 years. We find that the traditional institutions that governed Harenna’s resources persisted, in essence, over time. However, these institutions were modified repeatedly to address changes caused by varying formal, supra-regional governance regimes, the development of markets for forest products, increasing population pressure and changes in formal property rights. A key mechanism for adaptation was combining elements from both informal and formal institutions, which allowed traditional rules to persist in the guise of more formal arrangements. Our findings also highlight several constraints of institutional adaptation. For example, by abolishing fora for collective decision-making, regime changes limited adaptive capacity. To conclude, we argue that such insights into traditional resource governance and its adaptability and dynamics over time are essential to develop sustainable approaches to participatory forest management for the future, both in Harenna and more generally.  相似文献   
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