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131.
132.
Horsák M Hájek M Hájková P Cameron R Cernohorsky N Apostolova I 《Die Naturwissenschaften》2011,98(8):671-681
Mollusc communities of previously unexplored Bulgarian fens were studied in order to determine and generalise the patterns
of species richness and composition along the mineral richness gradient. The aim was also to compare predictive values of
the environment, vegetation and spatial structure. Altogether, 44 mollusc species were recorded at 40 treeless fen sites.
Species richness varied from 0 to 18 species per site, and it was positively associated with the mineral gradient and negatively
with altitude. However, the best predictor was obtained using plant species composition. All explanatory variables had higher
effect on land snails than on the entire mollusc assemblage (including aquatic species). Species richness and abundance were
significantly and positively correlated with the species composition turnover; the communities were highly nested, with poor
sites having subsets of the fauna found in the richest. The main direction of mollusc species turnover was highly associated
with that observed for vegetation, and the main gradient of plant species composition was able to explain nearly 20% of total
variation in mollusc data. We found that spatial structure explained by far the highest proportion of independent variation,
which reflected the high level of geographical isolation of Bulgarian fens and regional differences independent of any environmental
variation. Our results demonstrate (1) the general role of mineral richness gradient for structuring mollusc communities in
fens, (2) the pivotal indicator role of plant species composition in predicting species composition of mollusc communities,
despite being trophically independent and (3) the effect of isolation and origins of the habitat on species composition: most
species have wide geographical distributions within the habitat type, and geographical patterns within Bulgaria may have a
stochastic element. 相似文献
133.
Nicole Basenback Jeremy M. Testa Chunqi Shen 《Journal of the American Water Resources Association》2023,59(2):429-445
The effects of nutrient loading on estuaries are well studied, given the multitude of negative water quality and ecosystem effects that have been attributed to excess nitrogen and phosphorus. A current gap in this knowledge involves the sensitivity of seasonal cycles of estuarine biogeochemical processes to direct (warming) and indirect influences (nutrient load timing) of climate change. We used a coupled hydrologic–biogeochemical model to investigate changes in the phenology of hypoxia and related biogeochemical processes in Chesapeake Bay under three different hydrologic regimes. Shifts to earlier nutrient load timing during idealized simulations reduced the overall annual hypoxic volume, resulting from discernable, but relatively small reductions in phytoplankton biomass and both sediment and water-column respiration. Simulated increases in water temperature caused an increase in spring/early summer hypoxic volume associated with elevated respiration rates, but an associated exhaustion of organic matter in the early summer caused a decrease in late summer/fall hypoxic volume due to lowered respiration. Warming effects on hypoxia were larger than nutrient timing effects in scenarios where warming was restricted to spring and when it was applied to all months of the year. These idealized simulations begin the process of understanding the potential impacts of future climatic changes in the seasonal timing of key biogeochemical processes associated with eutrophication. 相似文献
134.
An awareness campaign decreases distracted driving among hospital employees at a rural trauma center
Navpreet Rana Melissa Ross Lisa LaRock Jennifer Mele Nicole Cumbo Lauren Colom 《Traffic injury prevention》2018,19(8):S165-S167
AbstractObjective: To evaluate whether an educational campaign on distracted driving will have an impact in a given community.Methods: Investigators were stationed in an employee parking lot of a 256-bed hospital to determine baseline distracted driving followed by a 4-week hospital-wide distracted-driving awareness campaign. The campaign included signs/posters in the hospital, a booth outside of the cafeteria with flyers, a large banner in the employee lot and an opportunity for people to sign a pledge form to drive distraction free. The same employee lot was observed at the same time of the day to re-assess distracted driving immediately following the campaign. The observations were repeated again one year later to evaluate the short and long-term impact of the campaign.Results: A total of 485 vehicles were observed pre-campaign, identifying 170 (35%) distracted drivers at baseline. The awareness campaign resulted in 525 people pledging to drive distraction free. Following the campaign, 495 vehicles were observed and the number of distracted drivers was 64 (12.9%), showing a significant decrease in the number of distracted drivers by 22.1% (p?<?0.01). One year later, 530 drivers were observed with 150 (28%) displaying one form of distraction.Conclusions: A local distracted driving educational campaign resulted in a significant decrease in the number of distracted drivers immediately following the campaign. However, one year after the campaign, there was an increase in distracted driving. The proportion of distracted drivers was still significantly lower than the initial rate of distracted-drivers. 相似文献
135.
Eric P. S. Baumer Francesca Polletta Nicole Pierski Geri K. Gay 《Environmental Communication: A Journal of Nature and Culture》2017,11(3):289-310
This paper explores a technique for mitigating framing effects in perceptions of global climate change. People's opinions on issues ranging from same sex marriage and the environment to free speech and health care have been shown to be influenced by the way in which the issue is presented: the metaphors, images, and catchphrases that communicate implicit normative messages about the issue. The work described here synthesizes insights from experimental research on moderators of framing effects and sociological research on frame reflection. Based on this synthesis, this paper describes a test of a simple highlighting technique for focusing respondents' attention on the framing operating in political materials. Results suggest that this intervention not only can reduce the opinion-shaping impact of frames but may also reduce ideological polarization. Implications include a better understanding of the mechanisms by which frames operate, techniques for making frame reflection possible among political non-elites, and recommendations for strengthening environmental groups' public communication strategies. 相似文献
136.
Michael?R.?AllshouseEmail author Gregory?N.?Ivey Ryan?J.?Lowe Nicole?L.?Jones C.?J.?Beegle-Krause Jiangtao?Xu Thomas?Peacock 《Environmental Fluid Mechanics》2017,17(3):473-483
Windage, the additional direct, wind-induced drift of material floating at the free surface of the ocean, plays a crucial role in the surface transport of biological and contaminant material. Lagrangian coherent structures (LCS) uncover the hidden organizing structures that underlie material transport by fluid flows. Despite numerous studies in which LCS ideas have been applied to ocean surface transport scenarios, such as oil spills, debris fields and biological material, there has been no consideration of the influence of windage on LCS. Here we investigate and demonstrate the impact of windage on ocean surface LCS via a case study of the ocean surrounding the UNESCO World Heritage Ningaloo coral reef coast in Western Australia. We demonstrate that the inclusion of windage is necessary when applying LCS to the study of surface transport of any floating material in the ocean. 相似文献
137.
Application of water quality indices and analysis of the surface water quality monitoring network in semiarid North-Central Chile 总被引:4,自引:0,他引:4
Espejo L Kretschmer N Oyarzún J Meza F Núñez J Maturana H Soto G Oyarzo P Garrido M Suckel F Amezaga J Oyarzún R 《Environmental monitoring and assessment》2012,184(9):5571-5588
Surface water quality has increasing importance worldwide and is particularly relevant in the semiarid North-Central Chile, where agriculture and mining activities are imposing heavy pressure on limited water resources. The current study presents the application of a water quality index in four watersheds of the 29°-33°S realm for the period 1999-2008, based on the Canadian Council of Ministers for the Environment approach and the Chilean regulation for irrigation water quality. In addition, two modifications to the index are tested and a comprehensive characterization of the existing monitoring network is performed through cluster analysis. The basins studied show fairly good water quality in the overall, specially the Limarí basin. On the other hand, the lower index values were obtained for the headwaters of Elqui, associated with the El Indio mining district. The first modification of the indicator (i.e., to consider parameters differentially according to their effect on human health or the environment) did not produce major differences with respect to the original index, given the generally good water quality. The second modification (i.e., to consider as threshold values the more restrictive figures derived from a set of regulations) yielded important differences in the indicator values. Finally, an adequate characterization of the monitoring network was obtained. The results presented spatial coherence and the information can be used as a basis for the optimization of the monitoring network if required. 相似文献
138.
139.
Manipulative field studies are useful for investigating cause-effect relationships between contamination and benthic community health. However, there are many challenges for creating environmentally relevant exposures and determining what measurements are necessary to correctly interpret the results. This study describes the physical and chemical changes in the properties of metal-spiked marine sediments deployed in four different locations for up to 11 months. The test sediments lost between 20% and 75% of their volume during the deployment period, with the greatest losses occurring at sites affected by strong hydrodynamic activity. More sediment was lost from clean treatments than those spiked with high metal concentrations and corresponded with differential recruitment of infauna to these treatments. In general, a greater proportion of spiked-metals remained at lower energy sites (48-85%) than at higher energy sites (15-48%). The decreased metal concentrations were attributed mostly to the loss of the metal-spiked sediments (through resuspension) and their dilution with sediments depositing from the surrounding environment. A range of recommendations are made for optimising the information gained from field-based studies using metal-spiked sediments. These include the careful documentation of physico-chemical sediment properties pre- and post-deployment, the use of co-located sediment traps and knowledge of site-specific hydrodynamic processes. 相似文献
140.
Nicole Riddell Gilles Arsenault Jeff Klein Alan Lough Chris H. Marvin Alan McAlees Robert McCrindle Gordia MacInnis Ed Sverko Sheryl Tittlemier Gregg T. Tomy 《Chemosphere》2009,74(11):1538-1543
1,2,5,6-Tetrabromocyclooctane (TBCO) is a commercial brominated flame retardant that is employed mainly as an additive in textiles, paints and plastics. Very little is known about its presence or behavior in the environment or its analysis. TBCO can exist as two diastereomers, the stereochemistries of which have not been previously reported. We have named the first eluting isomer, under HPLC conditions, as alpha-TBCO (α-TBCO) and the later eluting isomer as beta-TBCO (β-TBCO) when using an Acquity UPLC BEH C18 column with methanol/acetonitrile/water as the mobile phase. The structural elucidation of these two isomers was accomplished by 1H NMR spectroscopy, GC/MS, LC/MS and X-ray structure determinations. α-TBCO is (1R,2R,5S,6S)-1,2,5,6-tetrabromocyclooctane and β-TBCO is rac-(1R,2R,5R,6R)-1,2,5,6-tetrabromocyclooctane. As with some other brominated cycloaliphatic compounds, TBCO is thermally labile and the isomers easily interconvert. A thermal equilibrium mixture of α- and β-TBCO consists of approximately 15% and 85% of these isomers, respectively. Separation of the two diastereomers, with minimal thermal interconversion between them, is achievable by careful selection of GC-capillary column length and injector temperature. LC/MS analyses of TBCO also presents an analytical challenge due to poor resolution of the isomers on chromatographic stationary phases, and weak intensity of molecular ions (or major fragment ions) when using LC-ESI/MS. Only bromide ions were seen in the mass spectra. APCI and APPI also failed to produce the molecular ion with sufficient intensity for identification. 相似文献