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821.
D. Wilson Freshwater Andrew Hines Seth Parham Ami Wilbur Michelle Sabaoun Jennifer Woodhead Lad Akins Bruce Purdy Paula E. Whitfield Claire B. Paris 《Marine Biology》2009,156(6):1213-1221
Lionfish are popular aquarium fish from the Indo-Pacific that have invaded the western Atlantic. Two species, Pterois volitans and P. miles, were well established along the United States east coast before the first lionfish were reported from the Bahamas in 2004,
where they quickly dispersed throughout the archipelago by 2007. The source of the Bahamian lionfish invasion has been in
question because of the hypothesized low connectivity between Florida and Bahamas reef species as well as the temporal lag
in their arrival in the Bahamas. Mitochondrial control region haplotypes (680 bp) were determined and analyzed for lionfish
specimens from the Bahamas, North Carolina, and two sites within their native range (Indonesia and the Philippines). Exact
tests, pairwise F
st and AMOVA analyses all showed no significant differentiation between the Bahamas and North Carolina specimens. The similarity
between the Bahamas and North Carolina lionfish was also reflected in a minimum spanning network and neighbor-joining distance
tree generated from the data. Sequence analyses also revealed the presence of only Pterois volitans, as no P. miles were detected in the Bahamian sample. These results indicate that the source of the Bahamian lionfish is egg and larval dispersal
from the United States east coast population, and support previous models of reef fish dispersal that suggest a low level
of connectivity between the Bahamas and east coast of Florida. 相似文献
822.
823.
Marcelo Benetti Correa da Silva Ana Paula Graciola Gabriel Sperandio Milan Sulen Bebber Suane de Atayde Moschen Deonir De Toni 《环境质量管理》2019,28(4):75-84
Service quality in a construction technology laboratory can result in an improvement in construction companies’ competitiveness. This research aims to evaluate the service quality provided by a construction technology laboratory, specifically in the segment of performing testing through the rupturing of concrete samples. For this research, a survey was conducted using a structured questionnaire that was created based on a literature review regarding the surveying of laboratory customers at a university in the south of Brazil. Our research was both exploratory and quantitative, and the data were analyzed by applying multivariate data analysis. The conclusions of this study show that the dimensions of quality services are: communication, reliability, responsiveness, credibility, and tangibility. These five dimensions together provide a high explained variance standard of 79.75%. Having a suitable number of attendants available to serve customers and presenting agility in the construction laboratory is one of the managerial research contributions. Moreover, through information availability, this research generates greater traceability that can be used both by customers and by institutional management. Constantly and thoroughly monitoring the customer service cycle is another relevant factor that can improve the quality of the services provided. 相似文献
824.
Idalina Dias-Sardinha David Ross Ana Calapez Gomes 《Journal of Environmental Planning and Management》2018,61(4):635-655
The paper discusses conditions and format of a cluster model to support the management of a potential creative tourism destination in a setting where regional cross-sectoral collaboration is lacking. Creative tourism development requires a flexible framework and a healthy collaboration environment, more so when associated with resources shared by several stakeholders. This article focuses on the tourism potential of archaeological knowledge discovered during the environmental impact assessment of the Alqueva dam (Alentejo, Portugal). Interviews were conducted with 38 regional actors in the tourism and heritage sectors, as well as the dam developers and the companies responsible for archaeological interventions. Findings indicate that the lack of specific local policy addressing archaeological heritage hampers its potential use for tourism development, which is further aggravated by the absence of stakeholder communication and cooperation. A conceptual cluster model for the management of creative tourism destinations based on heritage resources and other local resources is proposed. 相似文献
825.
Artur Mielcarek Joanna Rodziewicz Wojciech Janczukowicz Arthur J. Thornton Tomasz Jó?wiak Paula Szymczyk 《环境科学学报(英文版)》2015,38(12):119-125
A series of investigations were conducted using sequencing batch biofilm reactor(SBBR) to explore the influence of C:N:P ratio on biological dephosphatation including the denitrifying dephosphatation and the denitrification process.Biomass in the reactor occurred mainly in the form of a biofilm attached to completely submerged disks.Acetic acid was used as the source of organic carbon.C:N:P ratios have had a significant effect on the profiles of phosphate release and phosphate uptake and nitrogen removal.The highest rates of phosphate release and phosphate uptake were recorded at the C:N:P ratio of 140:70:7.The C:N ratio of 2.5:1 ensured complete denitrification.The highest rate of denitrification was achieved at the C:N:P ratio of 140:35:7.The increase of nitrogen load caused an increase in phosphates removal until a ratio C:N:P of 140:140:7.Bacteria of the biofilm exposed to alternate conditions of mixing and aeration exhibited enhanced intracellular accumulation of polyphosphates.Also,the structure of the biofilm encouraged anaerobic–aerobic as well as anoxic–anaerobic and absolutely anaerobic conditions in a SBBR.These heterogeneous conditions in the presence of nitrates may be a significant factor determining the promotion of denitrifying polyphosphate accumulating organism(DNPAO) development. 相似文献
826.
827.
Patricia Palma Paula Alvarenga Vera L. Palma Rosa Maria Fernandes Amadeu M. V. M. Soares Isabel Rita Barbosa 《Environmental monitoring and assessment》2010,165(1-4):539-552
Multivariate statistical techniques were applied to evaluate spatial/temporal variations, and to interpret water quality data set obtained at Alqueva reservoir (south of Portugal). The water quality was monitored at nine different sites, along the water line, over a period of 18 months (from January 2006 to May 2007) using 26 water quality parameters. The cluster analysis allowed the formation of five different similarity groups between sampling sites, reflecting differences on the water quality at different locations of the Alqueva reservoir system. The PCA/FA identified six varifactors, which were responsible for 64% of total variance in water quality data set. The principal parameters, which explained the variability of quality water, were total phosphorus, oxidability, iron, parameters that at high concentrations indicate pollution from anthropogenic sources, and herbicides indicative of an intensive agricultural activity. The spatial analysis showed that the water quality was worse in the north of the reservoir. 相似文献
828.
Mourad Boulaid Ana Aguilera Valentina Busonera Francisco Camacho Antonio V. Monterreal Antonio Valverde 《Journal of environmental science and health. Part. B》2013,48(7):809-815
An analytical method, using supercritical fluid extraction (SFE), was assessed for residue analysis of the insecticides fipronil, acrinathrin and pyridaben and the fungicide kresoxim-methyl in melons. Extraction conditions were optimized on glass beads, as inert material, evaluating different pressures, temperatures, and CO2 volumes. Also, the extractability of pesticides from hydromatrix and anhydrous magnesium sulfate was evaluated. Both adsorbents were evaluated for the preparation of SFE-spiked melon samples. Extractions of fortified samples were done using 20 mL of CO2, 300 atm, and 50°C. Different extraction conditions, including the addition of water and methanol as a static modifier, were used to assess the extractability of these pesticides, and the addition of methanol was demonstrated to improve the extraction of all the studied pesticides. 相似文献
829.
Ana Mendon?a Concei??o Juana Fortes Rui Capit?o Maria da Gra?a Neves Theo Moura José Sim?o Antunes do Carmo 《Journal of Coastal Conservation》2012,16(4):543-553
This paper describes an application of the Boussinesq-type COULWAVE model to study the wave hydrodynamics in the vicinity of a multi-functional artificial reef (MFAR). This reef is under investigation and consists of a supplementary protection solution for the Leirosa sand dune system located at South of Figueira da Foz, on the Portuguese West coast. Such installation near the coastline is expected to contribute to enhance the surfing conditions in the area, protect the sand dune system in the surroundings of Leirosa beach, and increase its environmental value. Numerical calculations with the COULWAVE model were performed for four test cases, considering two reef geometries (differing in the reef angle) and two incident wave conditions (storm condition and a common wave condition). Comparisons between the results obtained, in terms of wave heights and breaking line positions allow us to assess the influence of the reef on the hydrodynamics near the beach and around the reef. Moreover, the reef performance was analysed in terms of surfability and coastal protection. The surfability parameters (breaker height, Iribarren number and peel angle) were calculated for each test case using the numerical wave heights, wave directions and wave breaking positions. Comparisons of parameters allow characterizing the most appropriate configuration of the reef to improve the surfing conditions in the study area. A methodology based on numerical free surface elevations and horizontal velocity components was developed to calculate wave directions, since this is not a direct output of the COULWAVE model. Concerning coastal protection, analyses of the mean currents around the reef were used together with observations of the velocity cells near the shoreline as an indication of the sediment transport. 相似文献
830.
Paula Kahumbu 《Conservation biology》2010,24(2):636-637