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101.
Jellyfish accumulations are often problematic for tourism and fisheries both along European coastlines and overseas. They damage the reputation of several seaside resorts and cause serious economic losses. On the German Baltic coast, jellyfish accumulations are well known, too. Besides population increase due to anthropogenic effects, normal hydrodynamic processes are notable key factors when it comes to jellyfish accumulations. Along German Baltic coastlines, moon jellyfish (Aurelia aurita) occur most frequently but also stinging lion??s mane jellyfish (Cyanea capillata) appear regularly, however not as abundant. The objectives of our study were a) to screen when, where, how many and which jellyfish species occur on German Baltic coasts, b) to find the causes for jellyfish accumulations and c) to evaluate how beach visitors perceive native medusae and whether information can influence their perception. Different methods where combined: systematic jellyfish observations in cooperation with lifeguards, investigations of jellyfish abundance in shallow water zones, and interviews with beach visitors. Our results suggest that jellyfish occurrence along the German Baltic coast correlates with offshore wind or shore-parallel wind, which cause upwelling events. In contrast, there is no evidence that frequency of jellyfish occurrence was dependent on water temperature in summer. In regard to tourism, we found that beach visitors who received information about jellyfish stated to feel significantly less bothered by medusae. Overall, this article addresses different methods to learn more about jellyfish accumulations and it shows information strategies in terms of improved beach management.  相似文献   
102.
Over 350 European Integrated Coastal Zone Management (ICZM) ‘best practice’ case studies are documented in the OURCOAST online public database, to ensure that lessons learned from experiences and practices are shared and improve coastal management practices. However, concrete criteria for ‘best practice’ are missing and a critical evaluation of the success of these case studies did not take place. We present an indicator-based tool and methodology that allows assessing the progress towards sustainability of ICZM measures. An indicator-based tool was applied to 18 thematically different coastal case studies using two different methods: a fast screening and an analysis in-depth assessment. Both methods used help to identify strengths and weaknesses of ICZM and their contribution to sustainable development. However, indicator scores were highly affected by evaluators’ background and perception. The tool is user-friendly and easy to apply, it indicates what progress has made towards sustainability and to which extent targets have been met.  相似文献   
103.
由于毒性评估项目很难与日渐增长的需要测试的污染物保持同步,所以较难将关注点集中在影响水生生态系统的最为生物相关的污染物上。由于评估潜在毒性污染物所造成的生物影响已被证明是有效的,内生性代谢物的研究(代谢组学)对于剔除那些较低可能造成生物影响的污染物或许有一定帮助,从而找出生物重要性最高的污染物。本研究在北美五大湖流域的18个地点针对置于笼中的黑头软口鲦(Pimephales promelas)进行实验。我们测定了水体温度和水样中的污染物浓度(目标污染物132种,检出86种),并使用1H-NMR谱测量了肝极性提取物中的内生性代谢物。利用偏最小二乘法回归来比对内生性代谢物的相对丰度与污染物浓度和环境温度。结果表明内生性极性代谢物的指标与最多49种污染物存在共同变化。因此我们认为至多52%的检出污染物与内生性代谢物变化的共同变化不显著,表明这些污染物很可能不会在这些地点造成可以检测到的影响。这是通过缩短对于实验地点有着潜在影响的污染物列表从而扫描出检出污染物生物相关性的第一步。类似的信息有助于风险评估者区分不同污染物的重要性并将重点毒性测试放在最为生物相关的污染物上。
精选自Nicol Janecko, Lucie Pokludova, Jana Blahova, Zdenka Svobodova, Ivan Literak. Linking field-based metabolomics and chemical analyses to prioritize contaminants of emerging concern in the Great Lakes basin. Environmental Toxicology and Chemistry: Volume 35, Issue 10, pages 2493–2502, October 2016.DOI: 10.1002/etc.3409
详情请见http://onlinelibrary.wiley.com/doi/10.1002/etc.3409/full
  相似文献   
104.
Pleistocene eustatic changes in sea level are often invoked to explain genetic divergence among marine organisms. However, molecular phylogenies have revealed relatively few examples of speciation events dating to the Pleistocene. We present a species-level hypothesis of the timing of evolution for the Pomacentrus coelestis species complex (Pomacentridae), based on the nuclear S7 intron and the mitochondrial Cytb gene, and reconstruct ancestral range distributions across the timetree. Ancestral range reconstruction suggests the complex originated in the Coral Triangle and East Indian Ocean, with subsequent range expansion outward from this region. We suggest that land barriers to dispersal (e.g., Indo-Pacific barrier) may be responsible for the divergence between Indian (P. alleni, P. similis, P. caeruleopunctatus, and P. caeruleus) and Pacific (P. micronesicus, P. auriventris, and P. coelestis) species groups, and subsequent isolation by Pleistocene sea-level fluctuations in certain areas of the Coral Triangle (glacial refugia) may play an important role in the diversification of this species complex. Additionally, our analyses show cryptic lineages within P. micronesicus and highlight the need for comprehensive sampling within and among species to reveal recent speciation events.  相似文献   
105.
Acid mine drainage (AMD), which contains high concentrations of sulphate and dissolved metals, is a serious environmental problem. It can be treated in situ by sulphate reducing bacteria (SRB), but effectiveness of the treatment process depends on the organic substrate chosen to supply the bacteria's carbon source. Six natural organic materials were characterized in order to investigate how well these promote sulphate reduction and metal precipitation by SRB. Maple wood chips, sphagnum peat moss, leaf compost, conifer compost, poultry manure and conifer sawdust were investigated in terms of their carbon (TOC, TIC, DOC) and nitrogen (TKN) content, as well as their easily available substances content (EAS). Single substrates, ethanol, a mixture of leaf compost (30% w/w), poultry manure (18% w/w), and maple wood chips (2% w/w), and the same mixture spiked with formaldehyde were then tested in a 70-day batch experiment to evaluate their performance in sulphate reduction and metal removal from synthetic AMD. Metal removal efficiency in batch reactors was as high as 100% for Fe, 99% for Mn, 99% for Cd, 99% for Ni, and 94% for Zn depending on reactive mixtures. Early metal removal (0-12d) was attributed to the precipitation of (oxy)hydroxides and carbonate minerals. The lowest metal and sulphate removal efficiency was found in the reactor containing poultry manure as the single carbon source despite its high DOC and EAS content. The mixture of organic materials was most effective in promoting sulphate reduction, followed by ethanol and maple wood chips, and single natural organic substrates generally showed low reactivity. Formaldehyde (0.015% (w/v)) provided only temporary bacterial inhibition. Although characterization of substrates on an individual basis provided insight on their chemical make-up, it did not give a clear indication of their ability to promote sulphate reduction and metal removal.  相似文献   
106.
Evaluating progress towards environmental sustainability goals can be difficult due to a lack of measurable benchmarks and insufficient or uncertain data. Marine settings are particularly challenging, as stakeholders and objectives tend to be less well defined and ecosystem components have high natural variability and are difficult to observe directly. Fuzzy logic expert systems are useful analytical frameworks to evaluate such systems, and we develop such a model here to formally evaluate progress towards sustainability targets based on diverse sets of indicators. Evaluation criteria include recent (since policy enactment) and historical (from earliest known state) change, type of indicators (state, benefit, pressure, response), time span and spatial scope, and the suitability of an indicator in reflecting progress toward a specific objective. A key aspect of the framework is that all assumptions are transparent and modifiable to fit different social and ecological contexts. We test the method by evaluating progress towards four Aichi Biodiversity Targets in Canadian oceans, including quantitative progress scores, information gaps, and the sensitivity of results to model and data assumptions. For Canadian marine systems, national protection plans and biodiversity awareness show good progress, but species and ecosystem states overall do not show strong improvement. Well-defined goals are vital for successful policy implementation, as ambiguity allows for conflicting potential indicators, which in natural systems increases uncertainty in progress evaluations. Importantly, our framework can be easily adapted to assess progress towards policy goals with different themes, globally or in specific regions.  相似文献   
107.
Human exposure to particulate matter (PM) has been associated with adverse health effects. While inhalation exposure to airborne PM is a prominent research subject, exposure to PM of geological origin (i.e., generated from soil/soil-like material) has received less attention. This review discusses the contaminants in PM of geological origin and their relevance for human exposure and then evaluates lung bioaccessibility assessment methods and their use. PM of geological origin can contain toxic elements as well as organic contaminants. Observed/predicted PM lung clearance times are long, which may lead to prolonged contact with lung environment. Thus, certain exposure scenarios warrant the use of in vitro bioaccessibility testing to predict lung bioavailability. Limited research is available on lung bioaccessibility test development and test application to PM of geological origin. For in vitro tests, test parameter variation between different studies and concerns about physiological relevance indicate a crucial need for test method standardization and comparison with relevant animal data. Research is recommended on (1) developing robust in vitro lung bioaccessibility methods, (2) assessing bioaccessibility of various contaminants (especially polycyclic aromatic hydrocarbons (PAHs)) in PM of diverse origin (surface soils, mine tailings, etc.), and (3) risk characterization to determine relative importance of exposure to PM of geological origin.  相似文献   
108.
The nerve agent sarin has recently been deployed by terrorists in a major city. The molecule is volatile and made its way to many victims by passing as vapor through a highly reactive medium. Here we estimate rates and pathways for the removal of gas phase sarin from a generalized urban atmosphere. Only information from the open scientific literature is used. By structure reactivity comparisons with the organophosphorus pesticides, hydroxyl radical hydrogen abstraction may occur in as little as one hour. Decomposition of side chains after hydroxyl attack leads to organic oxygenates which preserve the phosphonofluoridate and so toxicity. The aqueous aerosol surface is contacted in minutes and offers access to a range of dissolved nucleophiles. Substitution displaces the fluoride leaving group, giving safe phosphoric acid analogs. Because of uncertainties in the electron distribution and in aqueous decay mechanisms, the time constants must be viewed as lower limits.  相似文献   
109.
110.
The electronic computer has had a profound effect upon air pollution research activities. This paper discusses some of the ways in which Public Health Service scientists routinely make use of the computer. It is used as a data processor to handle the large volumes of data resulting from continuous air monitoring devices. More importantly, it is used to perform the very complex computations involved in various statistical analyses and mathematical model building. In future years computers may be used on a real-time basis to control the sources which emit pollutants to the atmosphere.  相似文献   
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