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851.
Predicted increases in coral disease outbreaks associated with climate change have implications for coral reef ecosystems
and the people and industries that depend on them. It is critical that coral reef managers understand these implications and
have the ability to assess and reduce risk, detect and contain outbreaks, and monitor and minimise impacts. Here, we present
a coral disease response framework that has four core components: (1) an early warning system, (2) a tiered impact assessment
program, (3) scaled management actions and (4) a communication plan. The early warning system combines predictive tools that
monitor the risk of outbreaks of temperature-dependent coral diseases with in situ observations provided by a network of observers
who regularly report on coral health and reef state. Verified reports of an increase in disease prevalence trigger a tiered
response of more detailed impact assessment, targeted research and/or management actions. The response is scaled to the risk
posed by the outbreak, which is a function of the severity and spatial extent of the impacts. We review potential management
actions to mitigate coral disease impacts and facilitate recovery, considering emerging strategies unique to coral disease
and more established strategies to support reef resilience. We also describe approaches to communicating about coral disease
outbreaks that will address common misperceptions and raise awareness of the coral disease threat. By adopting this framework,
managers and researchers can establish a community of practice and can develop response plans for the management of coral
disease outbreaks based on local needs. The collaborations between managers and researchers we suggest will enable adaptive
management of disease impacts following evaluating the cost-effectiveness of emerging response actions and incrementally improving
our understanding of outbreak causation. 相似文献
852.
古城旅游地旅游影响的居民感知研究——以黄山市歙县徽州古城为例 总被引:1,自引:0,他引:1
古城旅游地是独具中国传统魅力的重要旅游目的地,而古城居民是古城生命力之所在。以黄山市歙县徽州古城为案例地,运用因子分析法,提取了古城居民感知的3个积极影响公因子和2个消极影响公因子,通过均值的比较,分析了居民对旅游影响的总体感知与态度。在此基础上,采用Bonferroni多变量协方差分析法(MNOVA)进一步分析不同细分居民群体对旅游影响感知的差异,展望了未来居民利益诉求的转变方向,以期为政府部门、旅游管理部门、旅游规划部门提供有益参考,促进古城旅游业的可持续发展。 相似文献
853.
Flagships are one conservation education tool. We present a proposed flagship species fleet for environmental education in central Chile. Our methods followed recent flagship guidelines. We present our selection process and a detailed justification for the fleet of flagship species that we selected. Our results are a list of eight flagship species forming a flagship fleet, including two small- and medium-sized mammals, the degu (Octodon degus) and the culpeo fox (Lycalopex culpeaus), two birds, the turca (Pteroptochos megapoidius) and the burrowing owl (Athene cunicularia), the Chilean iguana (Calopistes palluma), the tarantula (Grammostola mollicoma), and two trees, the litre (Lithrea caustica) and the espino (Acacia caven). We then describe how these flagships can be deployed most effectively, describing their audience, effective narrative frames, and modes of presentation. We conclude that general selection rules paired with social science background data allow for an efficient selection process. 相似文献
854.
The interactions between metals (Ca2+ and Hg2+) and extracellular polymeric substances (EPS) extracted from the aerobic and anaerobic sludge in wastewater treatment reactors were investigated using a combination of zeta potential measurement and 3-dimensional excitation–emission matrix (EEM) fluorescence spectroscopy with parallel factor (PARAFAC) analysis. Results show that Ca2+ had no substantial effects on the EEM fluorescence spectra of the EPS, but their zeta potentials increased with the increasing Ca2+ dosage. However, Hg2+ had a significant effect on the EEM fluorescence spectra of the EPS, while their zeta potentials seemed not to be affected by the dose of Hg2+. The interactions between Hg2+ and EPS were elucidated using the fluorescence quenching with PARAFAC analysis, while the interactions between Ca2+ and EPS were evaluated by the zeta potential technique. The binding constants for Hg2+ and EPS were two orders of magnitude higher than those for Ca2+ and EPS, suggesting that the binding mechanisms between Ca2+ and EPS were different from those between Hg2+ and EPS. The results might be useful for understanding the roles of EPS in bacterial self-protection against heavy metals and the aggregate formation mechanisms through ionic bridging interactions. 相似文献
855.
Carlos Alberto A. de Almeida Carla G.B. Brenner Luciane Minetto Carlos A. Mallmann Ayrton F. Martins 《Chemosphere》2013
In this study, an analytical methodology was developed for the determination of psycho-active drugs in the treated effluent of the University Hospital at the Federal University of Santa Maria, RS – Brazil. Samples were collected from point A (Emergency) and point B (General effluent). The adopted methodology included a pre-concentration procedure involving the use of solid phase extraction and determination by liquid chromatography coupled to mass spectrometry. The limit of detection for bromazepam and lorazepam was 4.9 ± 1.0 ng L−1 and, for carbamazepine, clonazepam and diazepam was 6.1 ± 1.5 ng L−1. The limit of quantification was 30.0 ± 1.1 ng L−1, for bromazepam, clonazepam and lorazepam; for carbamazepine was 50.0 ± 1.8 ng L−1 and was 40.0 ± 1.0 ng L−1 for diazepam. The mean concentrations in the Emergency and General effluent treated currents were as follows: for bromazepam, 195 ± 6 ng L−1 and 137 ± 7 ng L−1; for carbamazepine, 590 ± 6 ng L−1 and 461 ± 10 ng L−1; for diazepam, 645 ± 1 ng L−1 and 571 ± 10 ng L−1; for lorazepam, 96 ± 7 ng L−1 and 42 ± 4 ng L−1; and for clonazepam, 134 ± 10 ng L−1 and 57 ± 10 ng L−1. A preliminary risk assessment was conducted: carbamazepine and diazepam require considerable attention owing to their environmental toxicity. The occurrence of these psychoactive-drugs and the environmental risks that they pose demonstrated the need for a more efficient treatment system. As far we are aware, there have been no comparable studies to this on the hazards of hospital effluents in Brazil, and very few that have carried out a risk assessment of psycho-active drugs in hospital effluent in general. 相似文献
856.
为探讨高效选择性回收污泥厌氧消化液中磷的离子交换方法,采用静态实验和动态实验研究了4种阴离子交换树脂(D213、D202、D301和DSQ)的磷回收性能,筛选了适合富磷污泥厌氧消化液选择性磷回收的高交换容量树脂。实验结果表明,D213、D202、D301和DSQ 4种树脂对正磷浓度为70 mg/L的厌氧消化液进行动态处理时,其最大穿透体积分别为3、7、17和90 BV;DSQ树脂磷交换容量远高于其他3种树脂,达到6 860 mg P/L湿树脂,是目前报道的高磷交换容量树脂的3~4倍;DSQ树脂能有效地抵抗厌氧消化液中有机质和硫酸根等阴离子的干扰;用NaOH溶液再生DSQ树脂并回收磷,磷洗脱率超过96%,洗脱液是高浓度含磷液,可作为磷矿石的优质替代品。研究表明,DSQ树脂是一种高效选择性分离磷的树脂,适用于污泥厌氧消化液的磷回收。 相似文献
857.
Abstract To test the effectiveness of California’s vehicle inspection/ maintenance (I/M) program, exclusive of vehicle-owner intervention, a fleet of more than 1,100 vehicles that previously had failed California’s Smog Check test were sent to randomly selected Smog Check stations in the Los Angeles area for covert inspections and repairs. The two-speed idle test was used for repairs. For those vehicles that were repaired at the first inspection, their FTP emission reductions were 25%, 14%, and 11% for hydrocarbons (HC), carbon monoxide (CO), and nitrogen oxides (NOx), respectively, although emissions testing for NOx was not performed at the Smog Check stations. Idle HC and CO emissions increased for 35% and 43% of the vehicles, respectively, after repairs. This data set shows that most vehicles that fail the Smog Check inspection are only marginal emitters, with 61% and 44% of the total potential for HC and CO emission reductions, respectively, coming from only 10% of the vehicles that currently fail the inspection. When the vehicles were rank-ordered by idle emissions from dirtiest to cleanest, emission reduction costs for the highest-emitting 10% of the fleet averaged $l,100/ton and $250/ton for HC and CO, respectively, attributing all the costs to each pollutant exclusively. For the remaining vehicles, costs increased dramatically. 相似文献
858.
J. L. Jones E. A. Sckuck R. W. Eldridge N. Endow F. W. Cranz 《Journal of the Air & Waste Management Association (1995)》2013,63(2):73-77
While snowflakes fell and Christmas carols heralded the imminent holiday, over 3000 delegates to the Third National Conference on Air Pollution were told to “Control Now for Clean Air.” They were told this in many ways by many people—by the Vice President of the United States; by the Secretary of the Department of Health, Education, and Welfare who summoned the Conference; and by senators, congressmen, governors, and mayors. Then eight panel sessions convened to discuss and to determine how to control now for clean air. Speakers from every section of American life addressed themselves to this subject; when they were finished, the eight session chairmen summarized what had been said, what had been, learned. These summaries appear on the following pages. 相似文献
859.
Water-soluble anionic polyacrylamide (WSPAM), which is used to reduce erosion in furrow irrigated fields and other agriculture applications, contains less than 0.05% acrylamide monomer (AMD). Acrylamide monomer, a potent neurotoxicant and suspected carcinogen, is readily dissolved and transported in flowing water. The study quantified AMD leaching losses from a WSPAM-treated corn (Zea mays L.) field using continuous extraction-walled percolation samplers buried at 1.2 m depth. The samplers were placed 30 and 150 m from the inflow source along a 180-m-long corn field. The field was furrow irrigated using WSPAM at the rate of 10 mg L(-1) during furrow advance. Percolation water and furrow inflows were monitored for AMD during and after three furrow irrigations. The samples were analyzed for AMD using a gas chromatograph equipped with an electron-capture detector. Furrow inflows contained an average AMD concentration of 5.5 microg L(-1). The AMD in percolation water samples never exceeded the minimum detection limit and the de facto potable water standard of 0.5 microg L(-1). The risk that ground water beneath these WSPAM-treated furrow irrigated soils will be contaminated with AMD appears minimal. 相似文献
860.
Larney FJ Olson AF Miller JJ DeMaere PR Zvomuya F McAllister TA 《Journal of environmental quality》2008,37(2):725-735
In the 1990s, restrictions on incineration encouraged the forest industry in western Canada to develop new uses for their wood residuals by product. One such use was as a replacement for cereal straw bedding in southern Alberta's beef cattle (Bos taurus) feedlot industry. However, use of carbon (C)-rich bedding, such as wood chips, had implications for subsequent composting of the feedlot manure, a practice that was being increasingly adopted. In a 3-yr study, we compared composting of wood chip-bedded manure (WBM) and barley (Hordeum vulgare L.) straw-bedded manure (SBM). There were no significant differences in temperature regimes of SBM and WBM, indicating similar rates of successful composting. Of 17 physical and chemical parameters, five showed significant (P < 0.10) differences due to bedding at the outset of composting (Day 0), and 11 showed significant differences at final sampling (Day 124). During composting (10 sampling times), seven parameters showed significant bedding effects, 16 showed significant time effects, and four showed a Bedding x Time interaction. Significantly lower (P < 0.10) losses of nitrogen (N) occurred with WBM (19%) compared with SBM (34%), which has positive implications for air quality and use as a soil amendment. Other advantages of WBM compost included significantly higher total C (333 vs. 210 kg Mg(-1) for SBM) and inorganic N (1.3 vs. 1.0 kg Mg(-1) for SBM) and significantly lower total phosphorus (4.5 vs. 5.3 kg Mg(-1) for SBM). Our results showed that wood chip bedding should not be a problem for subsequent composting of the manure after pen cleaning. In combination with other benefits, our findings should encourage the adoption of wood chips over straw as a bedding choice for southern Alberta feedlots. 相似文献