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431.
432.
Human–wildlife conflicts are commonly addressed by excluding, relocating, or lethally controlling animals with the goal of preserving public health and safety, protecting property, or conserving other valued wildlife. However, declining wildlife populations, a lack of efficacy of control methods in achieving desired outcomes, and changes in how people value animals have triggered widespread acknowledgment of the need for ethical and evidence‐based approaches to managing such conflicts. We explored international perspectives on and experiences with human–wildlife conflicts to develop principles for ethical wildlife control. A diverse panel of 20 experts convened at a 2‐day workshop and developed the principles through a facilitated engagement process and discussion. They determined that efforts to control wildlife should begin wherever possible by altering the human practices that cause human–wildlife conflict and by developing a culture of coexistence; be justified by evidence that significant harms are being caused to people, property, livelihoods, ecosystems, and/or other animals; have measurable outcome‐based objectives that are clear, achievable, monitored, and adaptive; predictably minimize animal welfare harms to the fewest number of animals; be informed by community values as well as scientific, technical, and practical information; be integrated into plans for systematic long‐term management; and be based on the specifics of the situation rather than negative labels (pest, overabundant) applied to the target species. We recommend that these principles guide development of international, national, and local standards and control decisions and implementation.  相似文献   
433.
Increasingly, total maximum daily load (TMDL) limits are being defined for agricultural watersheds. Reductions in non-point source pollution are often needed to meet TMDL limits, and improvements in management of annual crops appear insufficient to achieve the necessary reductions. Increased adoption of perennial crops and other changes in agricultural land use also appear necessary, but face major barriers. We outline a novel strategy that aims to create new economic opportunities for land-owners and other stakeholders and thereby to attract their voluntary participation in land-use change needed to meet TMDLs. Our strategy has two key elements. First, focused efforts are needed to create new economic enterprises that capitalize on the productive potential of multifunctional agriculture (MFA). MFA seeks to produce a wide range of goods and ecosystem services by well-designed deployment of annual and perennial crops across agricultural landscapes and watersheds; new revenue from MFA may substantially finance land-use change needed to meet TMDLs. Second, efforts to capitalize on MFA should use a novel methodology, the Communicative/Systemic Approach (C/SA). C/SA uses an integrative GIS-based spatial modeling framework for systematically assessing tradeoffs and synergies in design and evaluation of multifunctional agricultural landscapes, closely linked to deliberation and design processes by which multiple stakeholders can collaboratively create appropriate and acceptable MFA landscape designs. We anticipate that application of C/SA will strongly accelerate TMDL implementation, by aligning the interests of multiple stakeholders whose active support is needed to change agricultural land use and thereby meet TMDL goals.  相似文献   
434.
Behavioural observations of male copepods revealed that they commonly follow female footprints to find their mates. Copepods can perceive signals generated by females either hydromechanically or chemically. Signal intensity is affected by hydrodynamic conditions which clear chemical and mechanical cues and modulate copepod’s ability to sense signals of their biotic environment, such as in their search for mates. We studied the patterns and efficiency of the copepod Pseudodiaptomus annandalei to mate in calm and hydrodynamically disturbed waters, in illuminated and dark conditions in experimental containers of different shapes and volumes. Courtship in P. annandalei was a negative function of hydromechanical disturbance, since successful mating events were observed in calm water only. In weakly turbulent conditions (air-bubbling of 100 ml/min), males were not able to pursue females properly; swimming speed decreased about three times in comparison with that in calm water. In calm water conditions, sequential and simultaneous taxis mechanisms were used by P. annandalei males to pursue females. The ability of P. annandalei males to track a three-dimensional trail probably depended on the persistence of fluid-borne signals.  相似文献   
435.
Trends in atmospheric acid deposition and in soil solution acidity from 1995 or later until 2007 were investigated at several forest sites throughout Switzerland to assess the effects of air pollution abatements on deposition and the response of the soil solution chemistry. Deposition of the major elements was estimated from throughfall and bulk deposition measurements at nine sites of the Swiss Long-Term Forest Ecosystem Research network (LWF) since 1995 or later. Soil solution was measured at seven plots at four soil depths since 1998 or later. Trends in the molar ratio of base cations to aluminum (BC/Al) in soil solutions and in concentrations and fluxes of inorganic N (NO(3)-N + NH(4)-N), sulfate (SO(4)-S), and base cations (BC) were used to detect changes in soil solution chemistry. Acid deposition significantly decreased at three out of the nine study sites due to a decrease in total N deposition. Total SO(4)-S deposition decreased at the nine sites, but due to the relatively low amount of SO(4)-S load compared to N deposition, it did not contribute to decrease acid deposition significantly. No trend in total BC deposition was detected. In the soil solution, no trend in concentrations and fluxes of BC, SO(4)-S, and inorganic N were found at most soil depths at five out of the seven sites. This suggests that the soil solution reacted very little to the changes in atmospheric deposition. A stronger reduction in base cations compared to aluminum was detected at two sites, which might indicate that acidification of the soil solution was proceeding faster at these sites.  相似文献   
436.
A national dataset on concentrations of mercury in fish, compiled mainly from state and federal monitoring programs, was used to evaluate trends in mercury (Hg) in fish from US rivers and lakes. Trends were analyzed on data aggregated by site and by state, using samples of the same fish species and tissue type, and using fish of similar lengths. Site-based trends were evaluated from 1969 to 2005, but focused on a subset of the data from 1969 to 1987. Data aggregated by state were used to evaluate trends in fish Hg concentrations from 1988 to 2005. In addition, the most recent Hg fish data (1996?C2005) were compared to wet Hg deposition data from the Mercury Deposition Network (MDN) over the same period. Downward trends in Hg concentrations in fish from data collected during 1969?C1987 exceeded upward trends by a ratio of 6 to 1. Declining Hg accumulation rates in sediment and peat cores reported by many studies during the 1970s and 1980s correspond with the period when the most downward trends in fish Hg concentrations occurred. Downward Hg trends in both sediment cores and fish were also consistent with the implementation of stricter regulatory controls of direct releases of Hg to the atmosphere and surface waters during the same period. The southeastern USA had more upward Hg trends in fish than other regions for both site and state aggregated data. Upward Hg trends in fish from the southeastern USA were associated with increases in wet deposition in the region and may be attributed to a greater influence of global atmospheric Hg emissions in the southeastern USA. No significant trends were found in 62% of the fish species from six states from 1996 to 2005. A lack of Hg trends in fish in the more recent data was consistent with the lack of trends in wet Hg deposition at MDN sites and with relatively constant global emissions during the same time period. Although few significant trends were observed in the more recent Hg concentrations in fish, it is anticipated that Hg concentrations in fish will respond to changes in atmospheric Hg deposition, however, the magnitude and timing of the response is uncertain.  相似文献   
437.
Estuaries are marine areas at great contamination risk due to their hydrodynamic features. PAH are wide and ubiquitous contaminants with a high presence in these marine environments. Chemical analysis of sediments can provide information, although it does not give a direct measure of the toxicological effect of such contaminants in the biota. Samples of Venerupis pullastra, Cerastoderma edule, and Mytilus galloprovincialis were collected from two locations in Corcubión estuary (Norhwest of Spain). The level of PAH in sediment and biota, and its possible origin were assessed. A moderate level of contamination was observed with a predominance of PAH of a pyrogenic origin. Genotoxic damage, measured as single-strand DNA breaks with the comet assay, was evaluated in gill tissue and in hemolymph. The values of DNA damage obtained showed a higher sensitivity of clams and cockles to the pollution load level. These differences among species make us suggest the use of some other species coupled with mussels as an optimal tool for biomonitoring estuarine environments.  相似文献   
438.

Problem

As the evidence-based movement has advanced in public health, changes in public health practices have lagged far behind creating a science to service gap. For example, science has produced effective falls prevention interventions for older adults. It now is clearer WHAT needs to be done to reduce injury and death related to falls. However, issues have arisen regarding HOW to assure the full and effective uses of evidence-based programs in practice.

Summary

Lessons learned from the science and practice of implementation provide guidance for how to change practices by developing new competencies, how to change organizations to support evidence-based practices, and how to change public health systems to align system functions with desired practices. The combination of practice, organization, and system change likely will produce the public health benefits that are the promise of evidence-based falls prevention interventions.

Impact on public health

For the past several decades, the emphasis has been solely on evidence-based interventions. Public health will benefit from giving equal emphasis to evidence-based implementation.

Impact on Industry

We now have over two decades of research on the effectiveness of fall prevention interventions. The quality of this research is judged by a number of credible international organizations, including the Cochrane Collaboration (http://www.cochrane.org/), the American and British Geriatrics Societies, and the Campbell Collaboration (http://www.campbellcollaboration.org/). These international bodies were formed to ponder and answer questions related to the quality and relevance of research. These developments are a good first step. However, while knowing WHAT to do (an evidence-based intervention) is critical, we also need to know HOW to effectively implement the evidence. Implementation, organization change, and system change methods produce the conditions that allow and support the full and effective use of evidence-based interventions. It is time to focus on utilization of implementation knowledge in public health. Without this focus the vast amount on new evidence being generated on the prevention of falls and related injuries among older adults will have little impact on their health and safety.  相似文献   
439.
Environmental Science and Pollution Research - Three sampling campaigns were performed in the Lis River (Leiria, Portugal) in February of 2018, November of 2018, and May of 2019. River water and...  相似文献   
440.
We draw from social categorization theory and the actor–observer hypothesis to extend previous research regarding receiving high levels of help from team members. Specifically, we explore how a team member's performance feedback on how they handled a disproportionately heavy share of the team's workload and how their racial distance from the rest of their teammates affect the amount of helping that person receives from their teammates. Results from a laboratory study in which 79 teams worked on a computerized, decision‐making task demonstrated a three‐way interaction between workload, performance feedback, and the racial distance between the feedback recipient and the rest of their teammates. Racially distant negative feedback recipients who had a disproportionately heavy share of their team's workload received less help from teammates than their racially similar counterparts. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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