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481.
The levels of 21 PBDE congeners were detemined in the dust sampled from 66 personal automobiles. The dominant congener in automobile dust was BDE-209 with a median level of 8.12 μg g?1. Personal vehicle dust samples contained the characteristic profile of the PBDE congeners that comprise the PentaBDE and DecaBDE commercial formulations. Levels of PBDEs in personal automobiles are generally reduced in comparison to our previously reported levels in resale vehicles on dealership lots presumably due to a dilution effect introduced by dust or debris that does not originate from the vehicle. Laboratory photochemical studies were conducted on both automobile dust collected from personal vehicles as well as BDE-209 adsorbed to sodium sulfate. No significant degradation occurred in the personal vehicle dust after 56 days of constant UVA irradiation while significant degradation did occur with BDE-209 adsorbed to sodium sulfate. PBDEs from the degradation of BDE-209 were identified and potential degradation pathways elucidated. Human exposure potential to PBDEs from automobile dust ingestion remains a serious concern in the U.S. population. 相似文献
482.
Environmental and Ecological Statistics - 相似文献
483.
Kristy M. Ferraro Anthony L. Ferraro A. Z. Andis Arietta Nathalie R. Sommer 《Conservation biology》2023,37(4):e14101
Conservation science is a morally motivated field, with implicit and explicit values built into its practice. As such, conservationists must engage with conservation ethics to interrogate underlying values. We examine cutting-edge ecological science and contemporary ethics to revisit two conservation norms that have become dogmatic in the field: ecological collectives, but not individual animals, are valuable and anthropomorphism should be staunchly avoided. Emerging studies demonstrate that individuals and their intraspecific variation can be instrumentally valuable for conservation science, and there is an emerging consensus within environmental philosophy around the moral worth of individuals. Thus, we suggest conservation science should explicitly recognize the value of individuals. We also argue that avoiding anthropomorphism is detrimental to conservation because critical anthropomorphism enables a more nuanced scientific approach—allowing conservationists to ask enlightened questions with creativity and compassion. We provide evidence that both dogmatic norms are scientifically and morally outdated and propose new normative values to push conservation towards more robust science and ethical practice. 相似文献
484.
The influence of abiotic factors on the establishment and success of invasive species is often difficult to determine for
most marine ecosystems. However, examining this relationship is critical for predicting the spread of invasive species and
predicting which habitats will be most vulnerable to invasion. Here we examine the mortality and physiological sensitivity
to salinity of adult colonies of the colonial ascidians Botryllus schlosseri and Botrylloides violaceus. Adult colonies of each species were exposed to abrupt changes in salinity (5, 10, 15, 20, 25, 30 psu) in the laboratory.
Salinity ranges used in the laboratory corresponded with those of the field distributions of B. violaceus and B. schlosseri in the Great Bay Estuary, NH. Heart rate was used as a proxy for health to assess the condition of individual colonies. Heart
rates were monitored daily for approximately 2 weeks. Results revealed that both species experienced 100% mortality after
1 day at 5 psu and that their heart rates declined with decreasing salinity. Heart rates of B. schlosseri remained consistent between 15 and 30 psu and slowed at 10 psu. Heart rates of B. violaceus remained constant between 20 and 30 psu, but slowed at 15 psu. These laboratory results corresponded to the distribution
of these species in estuaries, indicating salinity is a key factor in the distribution and dominance of B. schlosseri and B. violaceus among coastal and estuarine sites. Furthermore, physiological differences to salinity were found between colonies of B. schlosseri in the Venetian Lagoon and colonies in Portsmouth Harbor, suggesting adaptation to environmental variables. 相似文献
485.
Talia Speaker Stephanie O'Donnell George Wittemyer Brett Bruyere Colby Loucks Anthony Dancer Marianne Carter Eric Fegraus Jonathan Palmer Ellie Warren Jennifer Solomon 《Conservation biology》2022,36(3):e13871
Conservation technology holds the potential to vastly increase conservationists’ ability to understand and address critical environmental challenges, but systemic constraints appear to hamper its development and adoption. Understanding of these constraints and opportunities for advancement remains limited. We conducted a global online survey of 248 conservation technology users and developers to identify perceptions of existing tools’ current performance and potential impact, user and developer constraints, and key opportunities for growth. We also conducted focus groups with 45 leading experts to triangulate findings. The technologies with the highest perceived potential were machine learning and computer vision, eDNA and genomics, and networked sensors. A total of 95%, 94%, and 92% respondents, respectively, rated them as very helpful or game changers. The most pressing challenges affecting the field as a whole were competition for limited funding, duplication of efforts, and inadequate capacity building. A total of 76%, 67%, and 55% respondents, respectively, identified these as primary concerns. The key opportunities for growth identified in focus groups were increasing collaboration and information sharing, improving the interoperability of tools, and enhancing capacity for data analyses at scale. Some constraints appeared to disproportionately affect marginalized groups. Respondents in countries with developing economies were more likely to report being constrained by upfront costs, maintenance costs, and development funding (p = 0.048, odds ratio [OR] = 2.78; p = 0.005, OR = 4.23; p = 0.024, OR = 4.26), and female respondents were more likely to report being constrained by development funding and perceived technical skills (p = 0.027, OR = 3.98; p = 0.048, OR = 2.33). To our knowledge, this is the first attempt to formally capture the perspectives and needs of the global conservation technology community, providing foundational data that can serve as a benchmark to measure progress. We see tremendous potential for this community to further the vision they define, in which collaboration trumps competition; solutions are open, accessible, and interoperable; and user-friendly processing tools empower the rapid translation of data into conservation action. Article impact statement: Addressing financing, coordination, and capacity-building constraints is critical to the development and adoption of conservation technology. 相似文献
486.
Sandström KJ Sunesson AL Levin JO Turner AP 《Journal of environmental monitoring : JEM》2003,5(3):477-482
In order to encourage more exposure measurements to be performed, a formic acid gas-phase biosensor has been developed for this purpose. In the present paper, an enzyme based biosensor has been validated with respect to analyte selectivity and on-site use. To ensure that the sampler developed measures the compound of interest the biosensor was exposed to three near structural homologues to formic acid, i.e. acetic acid, methanol and formaldehyde. These vapours were generated with and without formic acid and the only compound that was found to have an effect on the performance of the biosensor, albeit a small one, was acetic acid. The field test was performed in a factory using formic acid-containing glue for glulam products. In parallel to the measurements with the biosensor a well defined reference method was used for sampling and analysing formic acid. It was found that the biosensor worked satisfactorily in this environment when used in a stationary position. It was also shown that the biosensor could determine formic acid vapour concentrations down to 0.03 mg m(-3). 相似文献
487.
Alabodite?M.?George Anthony?KayEmail authorView authors OrcID profile 《Environmental Fluid Mechanics》2017,17(2):231-246
The behaviour of a discharge of warm water upwards into a homogeneous body of cold fresh water was investigated by means of a numerical model. The discharge has a parabolic velocity profile, with Reynolds number \(Re=50\), Prandtl number \(Pr=7\) and Froude number varied over the range \(0.2 \le {\rm Fr} \le 2.5\). Water density is taken to be a quadratic function of temperature, so that an initially positively buoyant discharge will experience buoyancy reversal as it mixes with an ambient below the temperature of maximum density. The resulting plume has some similarities to a fountain resulting from injection of negatively buoyant fluid upward into a less dense ambient. The plume is initially symmetric, but then its head detaches as it approaches its maximum height. The detached head is denser than the fluid in the plume below it, and the interaction between the sinking head and the rising plume causes a sideways deflection; as this cycle is repeated, the plume displays side-to-side flapping motion and vertical bobbing. As Froude number is increased (i.e. buoyancy reduced) the growth of the plume becomes slower, but the plume eventually reaches a greater height. We obtain empirical power-law scalings for maximum height and time taken to reach that height as functions of Froude number; these scalings are simlar to those for fountains with a linear dependence of density on temperature in the very weak regime. 相似文献
488.
A framework for practical and rigorous impact monitoring by field managers of marine protected areas
Monitoring is a crucial component of conservation in marine protected areas (MPAs) as it allows managers to detect changes to biodiversity and to infer cause of change. However, the complexities of sampling designs and associated statistical analyses can impede implementation of monitoring by managers. Two monitoring frameworks commonly used in marine environments are statistical testing and parameter estimation. For many managers these two approaches fail to help them detect change and infer causation for one or more reasons: the complexity of the statistical test, no decision-making structure and a sampling design that is suboptimal. In collaboration with marine park rangers in Egypt, we instigated a monitoring framework to detect impacts by snorkelers in a pragmatic but scientifically rigorous way. First, we used a literature review to define causal criteria to facilitate inference. This was essential because our sampling design was suboptimal due to a lack of baseline data and there was only one impact site. Second, we established a threshold level of coral damage that if exceeded would trigger management to reduce the impact of snorkelers. This provided a clear decision-making structure. Third, we estimated effect sizes with confidence intervals to detect change. For the field managers, this approach to detection was easier to understand than assessing a null hypothesis and provided critical information for decision making. At no stage during the short study period did snorkelers cause damage that exceeded the threshold and thus mitigation was not required. In situations of technical and financial constraints this framework will increase the implementation of effective impact monitoring for many activities in MPAs and enhance management of marine biodiversity. 相似文献
489.
Kramer DB Polasky S Starfield A Palik B Westphal L Snyder S Jakes P Hudson R Gustafson E 《Environmental management》2006,38(3):411-425
Roughly 45% of the assessed lakes in the United States are impaired for one or more reasons. Eutrophication due to excess
phosphorus loading is common in many impaired lakes. Various strategies are available to lake residents for addressing declining
lake water quality, including septic system upgrades and establishing riparian buffers. This study examines 25 lakes to determine
whether septic upgrades or riparian buffers are a more cost-effective strategy to meet a phosphorus reduction target. We find
that riparian buffers are the more cost-effective strategy in every case but one. Large transaction costs associated with
the negotiation and monitoring of riparian buffers, however, may be prohibiting lake residents from implementing the most
cost-effective strategy.
An erratum to this article is available at . 相似文献
490.