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181.
Environmental Geochemistry and Health - Soil Pb concentrations at urban agriculture sites (UAS) commonly exceed recommended safe levels. There is a lack of evidence regarding uptake of Pb by...  相似文献   
182.
Although protected areas represent a pivotal response to escalating anthropogenic threats, they face many pressures, inside and outside their boundaries. Amid these challenges, effective conservation is guided by evidence-based decision making supported by dynamic processes of learning and knowledge exchange. Although different models promote knowledge exchange, embedding research scientists within conservation agencies is best suited to supporting evidence-based conservation. Based on available literature and our experiences on several continents, we considered the benefits, challenges, and opportunities associated with embedding research scientists within conservation agencies and the research required to better understand the effectiveness of the embedding model for evidence-based conservation. Embedded researchers provide long-term commitment to building social capital among academic and nonacademic stakeholders; act as skilled gatekeepers who increase 2-way flow of knowledge between scientists and managers; attract, coordinate, and support management-relevant external research projects; drive the design and maintenance of long-term monitoring; and align their research with information needs. Notwithstanding the many benefits, research capacity of conservation agencies is declining worldwide. A significant challenge is that the values, structures, functions, and effectiveness of the embedding model of knowledge exchange remain poorly evaluated and documented. Also, embedded researchers have to balance their desire for creativity and flexibility with the standardization and quality control required by their public sector agencies; may be perceived as not credible because they are not truly independent of their agency; and have to couple scientific productivity with skills for transdisciplinary research, social facilitation, and stakeholder engagement. Systematic research on embedding and other models of knowledge exchange, across different world contexts, is required to better understand the benefits, costs, and institutional arrangements associated with different models.  相似文献   
183.
The high demand for conservation work is creating a need for conservation‐focused training of scientists. Although many people with postsecondary degrees in biology are finding careers outside academia, many programs and mentors continue to prepare students to follow‐in‐the‐footsteps of their professors. Unfortunately, information regarding how to prepare for today's conservation‐based job market is limited in detail and scope. This problem is complicated by the differing needs of conservation organizations in both economically developed and developing regions worldwide. To help scientists identify the tools needed for conservation positions worldwide, we reviewed the current global conservation job market and identified skills required for success in careers in academia, government, nonprofit, and for‐profit organizations. We also interviewed conservation professionals across all conservation sectors. Positions in nonprofit organizations were the most abundant, whereas academic jobs were only 10% of the current job market. The most common skills required across sectors were a strong disciplinary background, followed by analytical and technical skills. Academic positions differed the most from other types of positions in that they emphasized teaching as a top skill. Nonacademic jobs emphasized the need for excellent written and oral communication, as well as project‐management experience. Furthermore, we found distinct differences across job locations. Positions in developing countries emphasized language and interpersonal skills, whereas positions in countries with advanced economies focused on publication history and technical skills. Our results were corroborated by the conservation professionals we interviewed. Based on our results, we compiled a nondefinitive list of conservation‐based training programs that are likely to provide training for the current job market. Using the results of this study, scientists may be better able to tailor their training to maximize success in the conservation job market. Similarly, institutions can apply this information to create educational programs that produce graduates primed for long‐term success.  相似文献   
184.
Until around 1995 it was challenging to make the scientific results of research projects publicly available except through presentations at meetings or conferences, or as papers in academic journals. Then it began to be clear that the Internet could become the main medium to publish and share new information with a much wider audience. The DESIRE Project (desertification mitigation and remediation of land—a global approach for local solutions) has built on expertise gained in previous projects to develop an innovative online ‘Harmonized Information System’ (HIS). This documents the context, delivery and evaluation of all tasks in the DESIRE Project using non-scientific terminology, with much of it also available in the local languages of the study sites. The DESIRE-HIS makes use of new possibilities for communication, including video clips, interactive tools, and links to social media networks such as Twitter. Dissemination of research results using this approach has required careful planning and design. This paper sets out the steps that have culminated in a complete online Information System about local solutions to global land management problems in desertification-affected areas, including many practical guidelines for responsible land management. As many of those who are affected by desertification do not have Internet access, printable dissemination materials are also available on the DESIRE-HIS.  相似文献   
185.
Ecological interaction networks are a valuable approach to understanding plant-pollinator interactions at the community level. Highly structured daily activity patterns are a feature of the biology of many flower visitors, particularly provisioning female bees, which often visit different floral sources at different times. Such temporal structure implies that presence/absence and relative abundance of specific flower-visitor interactions (links) in interaction networks may be highly sensitive to the daily timing of data collection. Further, relative timing of interactions is central to their possible role in competition or facilitation of seed set among coflowering plants sharing pollinators. To date, however, no study has examined the network impacts of daily temporal variation in visitor activity at a community scale. Here we use temporally structured sampling to examine the consequences of daily activity patterns upon network properties using fully quantified flower-visitor interaction data for a Kenyan savanna habitat. Interactions were sampled at four sequential three-hour time intervals between 06:00 and 18:00, across multiple seasonal time points for two sampling sites. In all data sets the richness and relative abundance of links depended critically on when during the day visitation was observed. Permutation-based null modeling revealed significant temporal structure across daily time intervals at three of the four seasonal time points, driven primarily by patterns in bee activity. This sensitivity of network structure shows the need to consider daily time in network sampling design, both to maximize the probability of sampling links relevant to plant reproductive success and to facilitate appropriate interpretation of interspecific relationships. Our data also suggest that daily structuring at a community level could reduce indirect competitive interactions when coflowering plants share pollinators, as is commonly observed during flowering in highly seasonal habitats.  相似文献   
186.
The commercially and ecologically valuable sandeel (Ammodytes ssp.) make distinct vertical shifts between an inactive stage, during which they seek refuge in the sand, and a pelagic schooling stage, during which they forage. This characteristic discontinuous foraging pattern constitutes a challenge to fishery biologists and has consequences for a wide range of predators ranging from birds and mammals to commercially important species. However, experimental studies that shed light on the primary drivers of foraging activity in fish are rare. In the present study, whole schools of sandeel (A. tobianus) were caught in August in east Denmark (65°02′30N; 12°37′00E) and kept in large tanks in the laboratory. It was found that the amount of food ingested and memory of past days feeding history are primary drivers of foraging activity at the level of the entire school, whereas external factors such as prey concentration and temperature are merely secondary drivers.  相似文献   
187.
Most beneficial management practices (BMPs) recommended for reducing nutrient losses from agricultural land have been established and tested in temperate and humid regions. Previous studies on the effects of these BMPs in cold-climate regions, especially at the small watershed scale, are rare. In this study, runoff and water quality were monitored from 1999 to 2008 at the outlets of two subwatersheds in the South Tobacco Creek watershed in Manitoba, Canada. Five BMPs-a holding pond below a beef cattle overwintering feedlot, riparian zone and grassed waterway management, grazing restriction, perennial forage conversion, and nutrient management-were implemented in one of these two subwatersheds beginning in 2005. We determined that >80% of the N and P in runoff at the outlets of the two subwatersheds were lost in dissolved forms, ≈ 50% during snowmelt events and ≈ 33% during rainfall events. When all snowmelt- and rainfall-induced runoff events were considered, the five BMPs collectively decreased total N (TN) and total P (TP) exports in runoff at the treatment subwatershed outlet by 41 and 38%, respectively. The corresponding reductions in flow-weighted mean concentrations (FWMCs) were 43% for TN and 32% for TP. In most cases, similar reductions in exports and FWMCs were measured for both dissolved and particulate forms of N and P, and during both rainfall and snowmelt-induced runoff events. Indirect assessment suggests that retention of nutrients in the holding pond could account for as much as 63 and 57%, respectively, of the BMP-induced reductions in TN and TP exports at the treatment subwatershed outlet. The nutrient management BMP was estimated to have reduced N and P inputs on land by 36 and 59%, respectively, in part due to the lower rates of nutrient application to fields converted from annual crop to perennial forage. Overall, even though the proportional contributions of individual BMPs were not directly measured in this study, the collective reduction of nutrient losses from the five BMPs was substantial.  相似文献   
188.
Local Agenda 21s are now being widely produced throughout Britain. Whilst there is wide variation in the nature of such exercises, many are exceeding original expectations and opening up important new opportunities for community involvement in sustainable development. This paper argues that, if LA21s unlock the energies necessary to engage widespread participation in local quality of life issues, they can become an influential and enduring part of the governance of the local state. This raises a number of theoretical and practical issues relating to types of citizenship, social capital, appropriate participatory mechanisms, and the respective contributions of lay and technical expertise. Individual people who are pivotal to the dynamics of local sustainability strategies must themselves be sustained and supported throughout the process.  相似文献   
189.
190.
Forty percent of pregnant women aged 37 years and over do not have prenatal diagnosis despite being eligible for a free test. The present study aimed to determine how often, and which, untested women were making a choice about this, how many declined an offer and why. A questionnaire was given to untested women, aged 37 years and over, at no less than 24 weeks gestation. A total of 375 (81.5%) women declined, 72 (16%) were not offered a test and 13 presented too late antenatally. There was a three-fold increased likelihood (OR 3.10 95% CI 1.44, 6.65) of no offer for urban non-English speaking background women, compared with the reference group (metropolitan, English speaking). Unpartnered women were also significantly less likely to receive an offer (OR 3.18, 95% CI 1.19, 8.46). Risk to the baby was the main reason for declining. When offered non-invasive prenatal screening, most decliners of prenatal diagnosis accepted, even those who declined because they were opposed to abortion. We estimate that overall 33% of older pregnant women were being offered and declining amniocentesis and/or chorion villus sampling (CVS). Only 6% were not offered a test, but this small proportion is over-represented by minority groups who must be given equal opportunity to make this choice. Copyright © 2001 John Wiley & Sons, Ltd.  相似文献   
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