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Sample records for water diversion technique-designed

  1. Microbial water diversion technique-designed for near well treatment in low temperature sandstone reservoirs in the North Sea

    Energy Technology Data Exchange (ETDEWEB)

    Paulsen, J.E.; Vatland, A. [RF-Rogaland Research, Stavanger (Norway); Sorheim, R. [SINTEF, Oslo (Norway)] [and others

    1995-12-31

    A Norwegian Research Program on Improved Oil Recovery (IOR) in North Sea reservoirs was launched in 1992. Microbial methods, applied in this context, is a part of this program. The scope, the methodological approach, and results from the three first years are presented. Water profile control, using biomass to block high permeable zones of a reservoir, has been investigated using nitrate-reducing bacteria in the injected sea water as plugging agents. Emphasis has been put on developing a process that does not have disadvantages secondary to the process itself, such as souring and impairment of the overall injectivity of the field. Data from continuous culture studies indicate that souring may successfully be mitigated by adding nitrite to the injected seawater. The morphology and size of generic-nitrate-reducing seawater bacteria have been investigated. Screening of growth-promoting nutrients has been carried out, and some sources were detected as favorable. Transport and penetration of bacteria in porous media have been given special attention. Investigations with sand packs, core models, and pore micromodels have been carried out. The inherent problems connected with permeability contrasts and flow patterns, versus bacterial behavior, are believed to be critical for the success of this technology. Data from the transport and blocking experiments with the porous matrices confirm this concern. The technology is primarily being developed for temperatures less than 40{degrees}C.

  2. WATER DIVERSION MODEL

    Energy Technology Data Exchange (ETDEWEB)

    J.B. Case

    1999-12-21

    The distribution of seepage in the proposed repository will be highly variable due in part to variations in the spatial distribution of percolations. The performance of the drip shield and the backfill system may divert the water flux around the waste packages to the invert. Diversion will occur along the drift surface, within the backfill, at the drip shield, and at the Waste Package (WP) surface, even after the drip shield and WP have been breached by corrosion. The purpose and objective of this Analysis and Modeling Report (AMR) are to develop a conceptual model and constitutive properties for bounding the volume and rate of seepage water that flows around the drip shield (CRWMS M&O 1999c). This analysis model is to be compatible with the selected repository conceptual design (Wilkins and Heath, 1999) and will be used to evaluate the performance of the Engineered Barrier System (EBS), and to provide input to the EBS Water Distribution and Removal Model. This model supports the Engineered Barrier System (EBS) postclosure performance assessment for the Site Recommendation (SR). This document characterizes the hydrological constitutive properties of the backfill and invert materials (Section 6.2) and a third material that represents a mixture of the two. These include the Overton Sand which is selected as a backfill (Section 5.2), crushed tuff which is selected as the invert (Section 5.1), and a combined material (Sections 5.9 and 5.10) which has retention and hydraulic conductivity properties intermediate to the selected materials for the backfill and the invert. The properties include the grain size distribution, the dry bulk density and porosity, the moisture retention, the intrinsic permeability, the relative permeability, and the material thermal properties. The van Genuchten relationships with curve fit parameters are used to define the basic retention relationship of moisture potential to volumetric moisture content, and the basic relationship of unsaturated

  3. The Water Diversion Project

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    One of the basic characteristics of water distribution in China is that there is a deluge of water in the south and a deficiency in the north. To ease the water shortage in the north, the Chinese Government

  4. The microbial diversity of water kefir.

    Science.gov (United States)

    Gulitz, Anna; Stadie, Jasmin; Wenning, Mareike; Ehrmann, Matthias A; Vogel, Rudi F

    2011-12-15

    The microbial diversity of water kefir, made from a mixture of water, dried figs, a slice of lemon and sucrose was studied. The microbial consortia residing in the granules of three water kefirs of different origins were analyzed. A collection of 453 bacterial isolates was obtained on different selective/differential media. Bacterial isolates were grouped with randomly amplified polymorphic DNA (RAPD)-PCR analyses. One representative of each RAPD genotype was identified by comparative 16S rDNA gene sequencing. The predominant genus in water kefirs I and II was Lactobacillus, which accounted for 82.1% in water kefir I and 72.1% in water kefir II of the bacterial isolates. The most abundant species in water kefirs I and II were Lactobacillus hordei and Lb. nagelii followed by considerably lower numbers of Lb. casei. Other lactic acid bacteria (LAB) were identified as Leuconostoc mesenteroides and Lc. citreum in all three water kefirs. The most abundant species in water kefir III was Lc. mesenteroides (28%) and Lc. citreum (24.3%). A total of 57 LAB belonging to the species of Lb. casei, Lb. hordei, Lb. nagelii, Lb. hilgardii and Lc. mesenteroides were able to produce exopolysacchrides from sucrose. Non LABs were identified as Acetobacter fabarum and Ac. orientalis. The Acetobacter species were more prevalent in consortium III. Cluster analyses of RAPD-PCR patterns revealed an interspecies diversity among the Lactobacillus and Acetobacter strains. Aditionally, Saccharomyces cerevisiae, Lachancea fermentati, Hanseniaospora valbyensis and Zygotorulaspora florentina were isolated and identified by comparison of partial 26S rDNA sequences and FTIR spectroscopy. Copyright © 2011. Published by Elsevier B.V.

  5. Calculation of ecological compensation for water sources for water diversion projects

    Science.gov (United States)

    Su, H. B.; Zhang, T. M.; Hu, C. Y.; Long, L. Y.

    2016-08-01

    This study considers the compensation of water diversion projects for the values of the terrestrial biological resources, water environment, and aquatic biological resources in water sources. An analysis of capital dynamics was conducted, and the economic development coefficient was used to correct the current method for calculating ecological compensation. A model was constructed to calculatethe ecological compensation for the water sources for water diversion projects. This model was used to calculate the ecological compensation for the Niulanjiang River provided by the Niulanjiang River to the Dianchi Lake water diversion project, which was calculated to be 136,799,400 RMB. As long as we know the occupying area of the project, the change of the river net flow after diversion and the local average GDP, the ecological compensation for water sources could be calculated by the model. The proposed model for calculating the ecological compensation for water sources is simple and incorporates the compensation provided by water diversion projects for the various environmental effects on water sources. It provides a guarantee for the capital to be used for the environmental protection of water sources and facilitates the sustainable development of the ecological environments of water sources.

  6. Is water age a reliable indicator for evaluating water quality effectiveness of water diversion projects in eutrophic lakes?

    Science.gov (United States)

    Zhang, Xiaoling; Zou, Rui; Wang, Yilin; Liu, Yong; Zhao, Lei; Zhu, Xiang; Guo, Huaicheng

    2016-11-01

    Water diversion has been applied increasingly to promote the exchange of lake water and to control eutrophication of lakes. The accelerated water exchange and mass transport by water diversion can usually be represented by water age. But the responses of water quality after water diversion is still disputed. The reliability of using water age for evaluating the effectiveness of water diversion projects in eutrophic lakes should be thereby explored further. Lake Dianchi, a semi-closed plateau lake in China, has suffered severe eutrophication since the 1980s, and it is one of the three most eutrophic lakes in China. There was no significant improvement in water quality after an investment of approximately 7.7 billion USD and numerous project efforts from 1996 to 2015. After the approval of the Chinese State Council, water has been transferred to Lake Dianchi to alleviate eutrophication since December 2013. A three-dimensional hydrodynamic and water quality model and eight scenarios were developed in this study to quantity the influence of this water diversion project on water quality in Lake Dianchi. The model results showed that (a) Water quality (TP, TN, and Chla) could be improved by 13.5-32.2%, much lower than the approximate 50% reduction in water age; (b) Water exchange had a strong positive relationship with mean TP, and mean Chla had exactly the same response to water diversion as mean TN; (c) Water level was more beneficial for improving hydrodynamic and nutrient concentrations than variation in the diverted inflowing water volume; (d) The water diversion scenario of doubling the diverted inflow rate in the wet season with the water level of 1886.5 m and 1887 m in the remaining months was the best water diversion mode for mean hydrodynamics and TP, but the scenario of doubling the diverted inflow rate in the wet season with 1887 m throughout the year was optimum for mean TN and Chla; (e) Water age influenced the effectiveness of water diversion on the

  7. Diversity and antibiotic resistance in Pseudomonas spp. from drinking water.

    Science.gov (United States)

    Vaz-Moreira, Ivone; Nunes, Olga C; Manaia, Célia M

    2012-06-01

    Pseudomonas spp. are common inhabitants of aquatic environments, including drinking water. Multi-antibiotic resistance in clinical isolates of P. aeruginosa is widely reported and deeply characterized. However, the information regarding other species and environmental isolates of this genus is scant. This study was designed based on the hypothesis that members of the genus Pseudomonas given their high prevalence, wide distribution in waters and genetic plasticity can be important reservoirs of antibiotic resistance in drinking water. With this aim, the diversity and antibiotic resistance phenotypes of Pseudomonas isolated from different drinking water sources were evaluated. The genotypic diversity analyses were based on six housekeeping genes (16S rRNA, rpoD, rpoB, gyrB, recA and ITS) and on pulsed field gel electrophoresis. Susceptibility to 21 antibiotics of eight classes was tested using the ATB PSE EU (08) and disk diffusion methods. Pseudomonas spp. were isolated from 14 of the 32 sampled sites. A total of 55 non-repetitive isolates were affiliated to twenty species. Although the same species were isolated from different sampling sites, identical genotypes were never observed in distinct types of water (water treatment plant/distribution system, tap water, cup fillers, biofilm, and mineral water). In general, the prevalence of antibiotic resistance was low and often the resistance patterns were related with the species and/or the strain genotype. Resistance to ticarcillin, ticarcillin with clavulanic acid, fosfomycin and cotrimoxazol were the most prevalent (69-84%). No resistance to piperacillin, levofloxacin, ciprofloxacin, tetracycline, gentamicin, tobramycin, amikacin, imipenem or meropenem was observed. This study demonstrates that Pseudomonas spp. are not so widespread in drinking water as commonly assumed. Nevertheless, it suggests that water Pseudomonas can spread acquired antibiotic resistance, preferentially via vertical transmission.

  8. Detecting pin diversion from pressurized water reactors spent fuel assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Young S.; Sitaraman, Shivakumar

    2017-01-10

    Detecting diversion of spent fuel from Pressurized Water Reactors (PWR) by determining possible diversion including the steps of providing a detector cluster containing gamma ray and neutron detectors, inserting the detector cluster containing the gamma ray and neutron detectors into the spent fuel assembly through the guide tube holes in the spent fuel assembly, measuring gamma ray and neutron radiation responses of the gamma ray and neutron detectors in the guide tube holes, processing the gamma ray and neutron radiation responses at the guide tube locations by normalizing them to the maximum value among each set of responses and taking the ratio of the gamma ray and neutron responses at the guide tube locations and normalizing the ratios to the maximum value among them and producing three signatures, gamma, neutron, and gamma-neutron ratio, based on these normalized values, and producing an output that consists of these signatures that can indicate possible diversion of the pins from the spent fuel assembly.

  9. Prokaryotic phylogenetic diversity of Hungarian deep subsurface geothermal well waters.

    Science.gov (United States)

    Németh, Andrea; Szirányi, Barbara; Krett, Gergely; Janurik, Endre; Kosáros, Tünde; Pekár, Ferenc; Márialigeti, Károly; Borsodi, Andrea K

    2014-09-01

    Geothermal wells characterized by thermal waters warmer than 30°C can be found in more than 65% of the area of Hungary. The examined thermal wells located nearby Szarvas are used for heating industrial and agricultural facilities because of their relatively high hydrocarbon content. The aim of this study was to reveal the prokaryotic community structure of the water of SZR18, K87 and SZR21 geothermal wells using molecular cloning methods and Denaturing Gradient Gel Electrophoresis (DGGE). Water samples from the outflow pipes were collected in 2012 and 2013. The phylogenetic distribution of archaeal molecular clones was very similar in each sample, the most abundant groups belonged to the genera Methanosaeta, Methanothermobacter and Thermofilum. In contrast, the distribution of bacterial molecular clones was very diverse. Many of them showed the closest sequence similarities to uncultured clone sequences from similar thermal environments. From the water of the SZR18 well, phylotypes closely related to genera Fictibacillus and Alicyclobacillus (Firmicutes) were only revealed, while the bacterial diversity of the K87 well water was much higher. Here, the members of the phyla Thermodesulfobacteria, Proteobacteria, Nitrospira, Chlorobi, OP1 and OPB7 were also detected besides Firmicutes.

  10. Assessment of impact of water diversion projects on ecological water uses in arid region

    Institute of Scientific and Technical Information of China (English)

    Song-hao SHANG; Hui-jie WANG

    2013-01-01

    In arid regions, large-scale water diversion from rivers leads to significant changes in river flow regimes, which may have large impacts on ecological water uses of river-dependent ecosystems, such as river, lake, wetland, and riparian ecosystems. To assess the integrated impact of water diversion on ecological water uses, we proposed a hierarchy evaluation model composed of four layers representing the evaluation goal, sub-areas of the influenced region, evaluation criteria, and water diversion schemes, respectively. The evaluation criteria for different types of ecological water uses were proposed, and the analytical hierarchy process was used for the integrated assessment. For a river ecosystem, the percentage of mean annual flow was used to define the grade of environmental flow. For a lake ecosystem, water recharge to the lake to compensate the lake water losses was used to assess the ecological water use of a lake. The flooding level of the wetland and the groundwater level in the riparian plain were used to assess the wetland and riparian ecological water uses, respectively. The proposed model was applied to a basin in northern Xinjiang in northwest China, where both water diversion and inter-basin water transfer projects were planned to be carried out. Based on assessment results for the whole study area and two sub-areas, an appropriate scheme was recommended from four planning schemes. With the recommended scheme, ecological water uses of the influenced ecosystems can be maintained at an acceptable level. Meanwhile, economical water requirements can be met to a great extent.

  11. Assessment of climate change impact on water diversion strategies of Melamchi Water Supply Project in Nepal

    Science.gov (United States)

    Shrestha, Sangam; Shrestha, Manish; Babel, Mukand S.

    2017-04-01

    This paper analyzes the climate change impact on water diversion plan of Melamchi Water Supply Project (MWSP) in Nepal. The MWSP is an interbasin water transfer project aimed at diverting water from the Melamchi River of the Indrawati River basin to Kathmandu Valley for drinking water purpose. Future temperature and precipitation of the basin were predicted using the outputs of two regional climate models (RCMs) and two general circulation models (GCMs) under two representative concentration pathway (RCP) scenarios which were then used as inputs to Soil and Water Assessment Tool (SWAT) to predict the water availability and evaluate the water diversion strategies in the future. The average temperature of the basin is projected to increase by 2.35 to 4.25 °C under RCP 4.5 and RCP 8.5, respectively, by 2085s. The average precipitation in the basin is projected to increase by 6-18 % in the future. The annual water availability is projected to increase in the future; however, the variability is observed in monthly water availability in the basin. The water supply and demand scenarios of Kathmandu Valley was also examined by considering the population increase, unaccounted for water and water diversion from MWSP in the future. It is observed that even with the additional supply of water from MWSP and reduction of unaccounted for water, the Kathmandu Valley will be still under water scarcity in the future. The findings of this study can be helpful to formulate water supply and demand management strategies in Kathmandu Valley in the context of climate change in the future.

  12. Assessment of climate change impact on water diversion strategies of Melamchi Water Supply Project in Nepal

    Science.gov (United States)

    Shrestha, Sangam; Shrestha, Manish; Babel, Mukand S.

    2015-12-01

    This paper analyzes the climate change impact on water diversion plan of Melamchi Water Supply Project (MWSP) in Nepal. The MWSP is an interbasin water transfer project aimed at diverting water from the Melamchi River of the Indrawati River basin to Kathmandu Valley for drinking water purpose. Future temperature and precipitation of the basin were predicted using the outputs of two regional climate models (RCMs) and two general circulation models (GCMs) under two representative concentration pathway (RCP) scenarios which were then used as inputs to Soil and Water Assessment Tool (SWAT) to predict the water availability and evaluate the water diversion strategies in the future. The average temperature of the basin is projected to increase by 2.35 to 4.25 °C under RCP 4.5 and RCP 8.5, respectively, by 2085s. The average precipitation in the basin is projected to increase by 6-18 % in the future. The annual water availability is projected to increase in the future; however, the variability is observed in monthly water availability in the basin. The water supply and demand scenarios of Kathmandu Valley was also examined by considering the population increase, unaccounted for water and water diversion from MWSP in the future. It is observed that even with the additional supply of water from MWSP and reduction of unaccounted for water, the Kathmandu Valley will be still under water scarcity in the future. The findings of this study can be helpful to formulate water supply and demand management strategies in Kathmandu Valley in the context of climate change in the future.

  13. Genetic diversity of water use efficiency in Jerusalem artichoke (Helianthus tuberosus L.) germplasm

    Science.gov (United States)

    Genetic diversity in crop germplasm is an important resource for crop improvement, but information on genetic diversity is rare for Jerusalem artichoke, especially for traits related to water use efficiency. The objectives of this study were to investigate genetic variations for water use and water...

  14. Incorporating water consumption into crop water footprint: A case study of China's South-North Water Diversion Project.

    Science.gov (United States)

    Wei, Yuhang; Tang, Deshan; Ding, Yifan; Agoramoorthy, Govindasamy

    2016-03-01

    The crop water footprint (WF) indicates the consumption of water for a crop during the planting period, mainly through evapotranspiration. However, as irrigated agriculture accounts for nearly 25% of the global agriculture water usage, evaluation of WF during transportation becomes essential to improve the efficiency of irrigated agriculture. This study aims at building an improved WF model to understand how much WF is produced due to water diversion and how much crop WF increases during the transfer. The proposed model is then used to calculate the WF of four major crops in five provinces along China's South-North Water Transfer Project in two steps. First, the WF of the water transfer project (WFeng) is assessed in a supply chain analysis method. Second, a WF allocation model is built to distribute the project WF for each crop/province. The results show that the evaporation and seepage are the main sources of WFeng. Out of five provinces, two namely Tianjin and Hebei present higher WFblue and WF increase. A positive correlation between water diversion distance and crop WF increase is noted. Among the four crops, cotton presents higher WFblue and WF increase. The crops with higher WFblue tend to be more strongly influenced by the water diversion project, due to high irrigation water dependency. This analysis may expand the WF concept from an evaporation-related term to a term reflecting crop biological processes and water consumption by artificial irrigation projects. Thus, it may serve as an indicator for optimizing future objectives and strategies associated to water resource planning in China and elsewhere.

  15. The influence of South-North Water Diversion Middle-Line Project on agricultural water in Jingmen and countermeasures

    Science.gov (United States)

    Jiang, Li

    2017-08-01

    Based on the investigation, the author puts forward a variety of adverse impacts of South-North Water Diversion Middle-Line Project on agricultural water in Jingmen. For examples, the land resource utilization is reduced; the farmland irrigation water cannot be guaranteed; the pollution of agricultural water is very serious. Combining the characteristics of South - North Water Diversion Project with the agricultural development in Jingmen, some countermeasures are provided in this paper, such as enhancing soil-water protection relying on related laws and policies, developing water resources and optimizing the use of water sources, adjusting the planting structure by adopting water-saving irrigation projects, developing dry farming and water-saving agriculture, controlling water pollution, and so on.

  16. The Shanggongshan Tunnel Kunming Zhangjiuhe River Water Diversion and Water Supply Project

    Institute of Scientific and Technical Information of China (English)

    J. P. Kaegi; M. Bachmann; A. Colombi

    2004-01-01

    Kunming is the political and economical centre of the Yunnan Province in the south -west of China and one of the most beautiful historical and cultural cities in China. It is also one of the 14 cities in China that are severely short of water. In order to solve the supply problem and to allow for future development of the local society and economy, the "Kunming Zhangjiuhe River Water Diversion and Water Supply Project" was implemented. The total investment for the project is about USD 476 million.The objective is to establish a water supply system with a capacity of 0.6 million tons of water per day.Major parts of the project are:capacity by 0. 442 billion m3 and an annual water supply of 0. 245 billion m3;tunnels, but also some siphons);pacity of 0.4 million tons per day in the initial stage and 0.6 million tons per day once completed;length of 93.43 km;sons.Project completion is planned for the end of 2006.

  17. Research of water resources allocation of South-to-North Water Diversion East Route Project in Jiangsu Province ,Eastern China

    Science.gov (United States)

    Zeng, C.

    2015-12-01

    Optimized allocation of water resources is the important means of solving regional water shortage and can improve the utilization of water resources. Water resources allocation in the large-scale water diversion project area is the current research focus. This research takes the east route of the South-to-North Water Transfer Project in Jiangsu province as the research area, based on the hydrological model, agricultural irrigation quota model, and water project scheduling model, a water resources allocation model was constructed. The research carried on generalized regional water supply network, simulated the water supply, water demand and water deficit in agriculture, industry, life, ecology and lock under the status quo and planning engineering conditions. According to the results, the east route of the South-to-North Water Transfer Project is helpful to improve regional water shortage situation. The results showed that pump output increase by 2.8 billion cubic meters of water. On the conditions of P = 95%, 75% and 50%, compared with the benchmark year, water demand increases slightly due to the need of social and economic development in planning years, and water supply increased significantly because of new diversion ability. Water deficit are greatly reduced by 74.9% especially in the commonly drought condition because of the new project operation and optimized allocation of water resources.

  18. Microbial Species Diversity, Community Dynamics, and Metabolite Kinetics of Water Kefir Fermentation

    OpenAIRE

    Laureys, David; De Vuyst, Luc

    2014-01-01

    Water kefir is a sour, alcoholic, and fruity fermented beverage of which the fermentation is started with water kefir grains. These water kefir grains consist of polysaccharide and contain the microorganisms responsible for the water kefir fermentation. In this work, a water kefir fermentation process was followed as a function of time during 192 h to unravel the community dynamics, the species diversity, and the kinetics of substrate consumption and metabolite production. The majority of the...

  19. Diversity of free-living amoebae in a dual distribution (potable and recycled) water system

    Science.gov (United States)

    Free-living amoebae are known to facilitate the growth of water associated pathogens. This study, for the first time, explored the diversity of free-living amoebae in a dual distribution (potable and recycled) water system in Rouse Hill NSW, Australia. Water and biofilm samples w...

  20. A Comparison of Microbial Water Quality and Diversity for Ballast and Tropical Harbor Waters.

    Directory of Open Access Journals (Sweden)

    Charmaine Ng

    Full Text Available Indicator organisms and antibiotic resistance were used as a proxy to measure microbial water quality of ballast tanks of ships, and surface waters in a tropical harbor. The survival of marine bacteria in ballast tanks appeared to diminish over longer water retention time, with a reduction of cell viability observed after a week based on heterotrophic plate counts. Pyrosequencing of 16S rRNA genes showed distinct differences in microbial composition of ballast and harbor waters. The harbor waters had a higher abundance of operational taxonomic units (OTUs assigned to Cyanobacteria (Synechococcus spp. and α-proteobacteria (SAR11 members, while marine hydrocarbon degraders such as γ-proteobacteria (Ocenspirillaes spp., Thiotrchales spp. and Bacteroidetes (Flavobacteriales spp. dominated the ballast water samples. Screening of indicator organisms found Escherichia coli (E. coli, Enterococcus and Pseudomonas aeruginosa (P. aeruginosa in two or more of the ballast and harbor water samples tested. Vibrio spp. and Salmonella spp. were detected exclusively in harbor water samples. Using quantitative PCR (qPCR, we screened for 13 antibiotic resistant gene (ARG targets and found higher abundances of sul1 (4.13-3.44 x 102 copies/mL, dfrA (0.77-1.80 x10 copies/mL and cfr (2.00-5.21 copies/mL genes compared to the other ARG targets selected for this survey. These genes encode for resistance to sulfonamides, trimethoprim and chloramphenicol-florfenicol antibiotics, which are also known to persist in sediments of aquaculture farms and coastal environments. Among the ARGs screened, we found significant correlations (P<0.05 between ereA, ermG, cfr and tetO genes to one or more of the indicator organisms detected in this study, which may suggest that these members contribute to the environmental resistome. This study provides a baseline water quality survey, quantitatively assessing indicators of antibiotic resistance, potentially pathogenic organisms and a

  1. Location of diversions from the surface-water network of the Central Valley Hydrologic Model (CVHM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset contains the name and location for the diversions from the surface-water network for the Central Valley Hydrologic Model (CVHM). The Central...

  2. Monthly Diversions from the Surface-Water Network of the Central Valley Hydrologic Model (CVHM)

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This digital dataset contains the monthly diversions from the surface-water network for the Central Valley Hydrologic Model (CVHM). The Central Valley encompasses an...

  3. Zooplankton production, composition and diversity in the coastal waters of Goa

    Digital Repository Service at National Institute of Oceanography (India)

    Goswami, S.C.; Padmavati, G.

    Spatial and temporal variability in zooplankton production, composition and diversity in the coastal waters of Goa were studied. Zooplankton production was bimodal with primary peak during September-October and secondary peak during March...

  4. Diversity did not influence soil water use of tree clusters in a temperate mixed forest

    OpenAIRE

    Meißner, M; Köhler, M; D. Hölscher

    2013-01-01

    Compared to monocultures, diverse ecosystems are often expected to show more comprehensive resource use. However, with respect to diversity–soil-water-use relationships in forests, very little information is available. We analysed soil water uptake in 100 tree clusters differing in tree species diversity and species composition in the Hainich forest in central Germany. The clusters contained all possible combinations of five broadleaved tree species in one-, two- and t...

  5. Analysis of Appropriate Timescales for Water Diversion Permits in Brazil

    Science.gov (United States)

    Bof, Luiz Henrique Nobre; Pruski, Fernando Falco; da Silva, Luciano Meneses Cardoso; Justino, Flavio

    2013-02-01

    Agreement on the criteria for granting the right to use water resources between governing bodies represents a significant advance in the process of sharing water use. To aid water resource management agencies in optimizing water use, the impact of using different criteria for permitting water use in the Paracatu river basin, Brazil, was evaluated in this study. The streamflow criteria corresponding to 30 % of the annual Q7,10 (used by the governing body of Minas Gerais), 70 % of the annual Q95 (used by the governing body of the union), 30 % of the monthly Q7,10, and 70 % of the monthly Q95 were evaluated. The use of criteria based on the monthly streamflow allows for better management of water use because it allows for greater utilization of this resource in times when there is high water availability and imposes a more realistic restriction during critical periods. Substitution of the annual Q7,10 for the monthly Q7,10 significantly increases the streamflow permitted in some months, for example, from December to May. Use of the criterion of 70 % of the annual Q95 involves a high risk of drought in critical months, while the criterion of 70 % of the monthly Q95 minimizes this risk.

  6. Sediment enzyme activities and microbial community diversity in an oligotrophic drinking water reservoir, eastern China.

    Science.gov (United States)

    Zhang, Haihan; Huang, Tinglin; Liu, Tingting

    2013-01-01

    Drinking water reservoir plays a vital role in the security of urban water supply, yet little is known about microbial community diversity harbored in the sediment of this oligotrophic freshwater environmental ecosystem. In the present study, integrating community level physiological profiles (CLPPs), nested polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis (DGGE) and clone sequence technologies, we examined the sediment urease and protease activities, bacterial community functional diversity, genetic diversity of bacterial and fungal communities in sediments from six sampling sites of Zhou cun drinking water reservoir, eastern China. The results showed that sediment urease activity was markedly distinct along the sites, ranged from 2.48 to 11.81 mg NH₃-N/(g·24 h). The highest average well color development (AWCD) was found in site C, indicating the highest metabolic activity of heterotrophic bacterial community. Principal component analysis (PCA) revealed tremendous differences in the functional (metabolic) diversity patterns of the sediment bacterial communities from different sites. Meanwhile, DGGE fingerprints also indicated spatial changes of genetic diversity of sediment bacterial and fungal communities. The sequence BLAST analysis of all the sediment samples found that Comamonas sp. was the dominant bacterial species harbored in site A. Alternaria alternate, Allomyces macrogynus and Rhizophydium sp. were most commonly detected fungal species in sediments of the Zhou cun drinking water reservoir. The results from this work provide new insights about the heterogeneity of sediment microbial community metabolic activity and genetic diversity in the oligotrophic drinking water reservoir.

  7. Boom clay borehole water, home of a diverse bacterial community

    Energy Technology Data Exchange (ETDEWEB)

    Wouters, Katinka; Moors, Hugo; Leys, Natalie [Belgian Nuclear Research Centre (SCK-CEN), Mol (Belgium)

    2013-07-01

    For over two decades, Boom Clay has been studied in the framework of geological disposal of nuclear waste thereby mainly addressing its geochemical properties. Today, also the microbiological properties and the possibility of microbes interacting with radionuclides or repository components including the waste form, in a host formation like Boom Clay are considered [2,3]. In the past, a reference composition for synthetic Boom Clay pore water (BCPW) was derived, based on interstitial water sampled from different layers within the Boom clay [1]. Similarly, the primary aim of this microbiological study was to determine the core BCPW bacterial community and identify representative water samples for future microbial directed lab experiments. In this respect, BCPW was sampled from different Boom Clay layers using the Morpheus piezometer and subsequently analysed by microscopy and molecular techniques, in search for overall shared and abundant micro-organisms. (authors)

  8. Application of an Environmental Decision Support System to a Water Quality Trading Program Affected by Surface Water Diversions

    Science.gov (United States)

    Obropta, Christopher C.; Niazi, Mehran; Kardos, Josef S.

    2008-12-01

    Environmental decision support systems (EDSSs) are an emerging tool used to integrate the evaluation of highly complex and interrelated physicochemical, biological, hydrological, social, and economic aspects of environmental problems. An EDSS approach is developed to address hot-spot concerns for a water quality trading program intended to implement the total maximum daily load (TMDL) for phosphorus in the Non-Tidal Passaic River Basin of New Jersey. Twenty-two wastewater treatment plants (WWTPs) spread throughout the watershed are considered the major sources of phosphorus loading to the river system. Periodic surface water diversions to a major reservoir from the confluence of two key tributaries alter the natural hydrology of the watershed and must be considered in the development of a trading framework that ensures protection of water quality. An EDSS is applied that enables the selection of a water quality trading framework that protects the watershed from phosphorus-induced hot spots. The EDSS employs Simon’s (1960) three stages of the decision-making process: intelligence, design, and choice. The identification of two potential hot spots and three diversion scenarios enables the delineation of three management areas for buying and selling of phosphorus credits among WWTPs. The result shows that the most conservative option entails consideration of two possible diversion scenarios, and trading between management areas is restricted accordingly. The method described here is believed to be the first application of an EDSS to a water quality trading program that explicitly accounts for surface water diversions.

  9. Cost analysis of water and sediment diversions to optimize land building in the Mississippi River delta

    Science.gov (United States)

    Kenney, Melissa A.; Hobbs, Benjamin F.; Mohrig, David; Huang, Hongtai; Nittrouer, Jeffrey A.; Kim, Wonsuck; Parker, Gary

    2013-06-01

    Land loss in the Mississippi River delta caused by subsidence and erosion has resulted in habitat loss and increased exposure of settled areas to storm surge risks. There is debate over the most cost-efficient and geomorphologically feasible projects to build land by river diversions, namely, whether a larger number of small, or a lesser number of large, engineered diversions provide the most efficient outcomes. This study uses an optimization framework to identify portfolios of diversions that are efficient for three general restoration objectives: maximize land built, minimize cost, and minimize water diverted. The framework links the following models: (1) a hydraulic water and sediment diversion model that, for a given structural design for a diversion, estimates the volume of water and sediment diverted; (2) a geomorphological land-building model that estimates the amount of land built over a time period, given the volume of water and sediment; and (3) a statistical model of investment cost as a function of diversion depth and width. An efficient portfolio is found by optimizing one objective subject to constraints on achievement of the other two; then by permuting those constraints, we find distinct portfolios that represent trade-offs among the objectives. Although the analysis explores generic relationships among size, cost, and land building (and thus does not consider specific project proposals or locations), the results demonstrate that large-scale land building (>200 km2) programs that operate over a time span of 50 years require deep diversions because of the enhanced efficiency of sand extraction per unit water. This conclusion applies whether or not there are significant scale economies or diseconomies associated with wider and deeper diversions.

  10. Bacterial Diversity in a Mine Water Treatment Plant▿ †

    Science.gov (United States)

    Heinzel, Elke; Hedrich, Sabrina; Janneck, Eberhard; Glombitza, Franz; Seifert, Jana; Schlömann, Michael

    2009-01-01

    We investigated the microbial community in a pilot plant for treatment of acid mine water by biological ferrous iron oxidation using clone library analysis and calculated statistical parameters for further characterization. The microbial community in the plant was conspicuously dominated by a group of Betaproteobacteria affiliated with “Ferribacter polymyxa”. PMID:19047391

  11. Study on Fishery Ecological Environment and Fish Species Diversity in Yantan Water Area

    Institute of Scientific and Technical Information of China (English)

    Yaoquan; HAN; Anyou; HE; Li; HUANG; Jun; SHI; Dapeng; WANG; Weijun; WU

    2015-01-01

    Through analysis on water quality,planktonic organism,fish resources,and fish species diversity in Yantan water area,this paper evaluated current situation of quality of fishery ecological environment in Yantan water area. The survey recorded all 52365 fishes and 1410. 2kg catches obtained by fishermen in half a year,and more than 98% catches are small fishes. The Shannon-Weiner diversity index of Yantan water area is 0. 162,Wilhm improvement index is 1. 814,DG- Findex is 0. 083,and the index of fish species diversity is far lower than other water areas. The average quantity per unit of phytoplankton is 1. 0134 million ind. / L,and the average quantity per unit of organisms is 1. 1151 mg / L. The average quantity per unit of zooplankton is 459. 6 ind. / L,and the average quantity per unit of organisms is 0. 6422 mg / L. Evaluation results indicate that water quality and planktonic organism in Yantan water area are basically normal,but fish resources are increasingly exhausted,fish resource composition is not reasonable,and fish species diversity is extremely low. From the perspective of biomanipulation,it is required to restore fishery ecological environment of reservoir area through restoring normal composition of aquatic organisms.

  12. Filamentous cyanoprokaryotes (Cyanoprokaryota/Cyanobacteria in standing waters of Bulgaria: diversity and ecology

    Directory of Open Access Journals (Sweden)

    PLAMEN STOYANOV

    2016-04-01

    Full Text Available Cyanoprokaryotes are widespread organisms, which dominate in different water basins. In the present study, we have investigated the diversity of this group and related physicochemical parameters in 35 standing water basins in Bulgaria. We found 29 cyanoprokaryotic species, which belong to 13 genera from the orders Synechococcales, Spirulinales and Oscillatoriales. The frequency quotient of each species was calculated. Information about the distribution of the identified species and typology of the water basins is also provided.

  13. Genotypic Diversity of Escherichia coli in the Water and Soil of Tropical Watersheds in Hawaii ▿

    OpenAIRE

    Goto, Dustin K.; Yan, Tao

    2011-01-01

    High levels of Escherichia coli were frequently detected in tropical soils in Hawaii, which present important environmental sources of E. coli to water bodies. This study systematically examined E. coli isolates from water and soil of several watersheds in Hawaii and observed high overall genotypic diversity (35.5% unique genotypes). In the Manoa watershed, fewer than 9.3% of the observed E. coli genotypes in water and 6.6% in soil were shared between different sampling sites, suggesting the ...

  14. Unscreened water-diversion pipes pose an entrainment risk to the threatened green sturgeon, Acipenser medirostris.

    Directory of Open Access Journals (Sweden)

    Timothy D Mussen

    Full Text Available Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (35±0.6 cm mean fork length to entrainment in a large (>500-kl outdoor flume with a 0.46-m-diameter water-diversion pipe. Fish entrainment was generally high (range: 26-61%, likely due to a lack of avoidance behavior prior to entering inescapable inflow conditions. We estimated that up to 52% of green sturgeon could be entrained after passing within 1.5 m of an active water-diversion pipe three times. These data suggest that green sturgeon are vulnerable to unscreened water-diversion pipes, and that additional research is needed to determine the potential impacts of entrainment mortality on declining sturgeon populations. Data under various hydraulic conditions also suggest that entrainment-related mortality could be decreased by extracting water at lower diversion rates over longer periods of time, balancing agricultural needs with green sturgeon conservation.

  15. Unscreened water-diversion pipes pose an entrainment risk to the threatened green sturgeon, Acipenser medirostris.

    Science.gov (United States)

    Mussen, Timothy D; Cocherell, Dennis; Poletto, Jamilynn B; Reardon, Jon S; Hockett, Zachary; Ercan, Ali; Bandeh, Hossein; Kavvas, M Levent; Cech, Joseph J; Fangue, Nann A

    2014-01-01

    Over 3,300 unscreened agricultural water diversion pipes line the levees and riverbanks of the Sacramento River (California) watershed, where the threatened Southern Distinct Population Segment of green sturgeon, Acipenser medirostris, spawn. The number of sturgeon drawn into (entrained) and killed by these pipes is greatly unknown. We examined avoidance behaviors and entrainment susceptibility of juvenile green sturgeon (35±0.6 cm mean fork length) to entrainment in a large (>500-kl) outdoor flume with a 0.46-m-diameter water-diversion pipe. Fish entrainment was generally high (range: 26-61%), likely due to a lack of avoidance behavior prior to entering inescapable inflow conditions. We estimated that up to 52% of green sturgeon could be entrained after passing within 1.5 m of an active water-diversion pipe three times. These data suggest that green sturgeon are vulnerable to unscreened water-diversion pipes, and that additional research is needed to determine the potential impacts of entrainment mortality on declining sturgeon populations. Data under various hydraulic conditions also suggest that entrainment-related mortality could be decreased by extracting water at lower diversion rates over longer periods of time, balancing agricultural needs with green sturgeon conservation.

  16. Plant functional diversity increases grassland productivity-related water vapor fluxes: an Ecotron and modeling approach.

    Science.gov (United States)

    Milcu, Alexandru; Eugster, Werner; Bachmann, Dörte; Guderle, Marcus; Roscher, Christiane; Gockele, Annette; Landais, Damien; Ravel, Olivier; Gessler, Arthur; Lange, Markus; Ebeling, Anne; Weisser, Wolfgang W; Roy, Jacques; Hildebrandt, Anke; Buchmann, Nina

    2016-08-01

    The impact of species richness and functional diversity of plants on ecosystem water vapor fluxes has been little investigated. To address this knowledge gap, we combined a lysimeter setup in a controlled environment facility (Ecotron) with large ecosystem samples/monoliths originating from a long-term biodiversity experiment (The Jena Experiment) and a modeling approach. Our goals were (1) quantifying the impact of plant species richness (four vs. 16 species) on day- and nighttime ecosystem water vapor fluxes; (2) partitioning ecosystem evapotranspiration into evaporation and plant transpiration using the Shuttleworth and Wallace (SW) energy partitioning model; and (3) identifying the most parsimonious predictors of water vapor fluxes using plant functional-trait-based metrics such as functional diversity and community weighted means. Daytime measured and modeled evapotranspiration were significantly higher in the higher plant diversity treatment, suggesting increased water acquisition. The SW model suggests that, at low plant species richness, a higher proportion of the available energy was diverted to evaporation (a non-productive flux), while, at higher species richness, the proportion of ecosystem transpiration (a productivity-related water flux) increased. While it is well established that LAI controls ecosystem transpiration, here we also identified that the diversity of leaf nitrogen concentration among species in a community is a consistent predictor of ecosystem water vapor fluxes during daytime. The results provide evidence that, at the peak of the growing season, higher leaf area index (LAI) and lower percentage of bare ground at high plant diversity diverts more of the available water to transpiration, a flux closely coupled with photosynthesis and productivity. Higher rates of transpiration presumably contribute to the positive effect of diversity on productivity.

  17. Nearshore marine fish diversity in southern California using trawl information from the Southern California Coastal Water Research Project.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This is a point file of mean fish diversity within 5 minute grid cells. The Shannon Index of diversity was calculated from Southern California Coastal Water Research...

  18. A Novel Bandwidth Efficient Transmit Diversity Scheme Based on Water-filling

    Institute of Scientific and Technical Information of China (English)

    SHENCong; DAILin; ZHOUShidong; YAOYan

    2004-01-01

    In this paper we propose a novel bandwidth efficient transmit diversity scheme based on layered space-time architecture, in which Channel state information (CSI) is fully utilized to maximize channel capacity according to water-filling principle. It is shown that compared with V-BLAST, this new scheme can maintain the same high bandwidth efficiency, but achieve much better performance thanks to more effective transmission power allocation and diversity gain.

  19. Life cycle assessment of water supply alternatives in water-receiving areas of the South-to-North Water Diversion Project in China.

    Science.gov (United States)

    Li, Yi; Xiong, Wei; Zhang, Wenlong; Wang, Chao; Wang, Peifang

    2016-02-01

    To alleviate the water shortage in northern China, the Chinese government launched the world's largest water diversion project, the South-to-North Water Diversion Project (SNWDP), which delivers water from water-sufficient southern China to water-deficient northern China. However, an up-to-date study has not been conducted to determine whether the project is a favorable option to augment the water supply from an environmental perspective. The life cycle assessment (LCA) methodology integrated with a freshwater withdrawal category (FWI) was adopted to compare water supply alternatives in the water-receiving areas of the SNWDP, i.e., water diversion, wastewater reclamation and seawater desalination. Beijing, Tianjin, Jinan and Qingdao were studied as representative cities because they are the primary water-receiving areas of the SNWDP. The results revealed that the operation phase played the dominant role in all but one of the life cycle impact categories considered and contributed to more than 70% of their scores. For Beijing and Tianjin, receiving water through the SNWDP is the most sustainable option to augment the water supply. The result can be drawn in all of the water-receiving areas of the middle route of the SNWDP. For Jinan and Qingdao, the most sustainable option is the wastewater reclamation system. The seawater desalination system obtains the highest score of the standard impact indicators in all of the study areas, whereas it is the most favorable water supply option when considering the freshwater withdrawal impact. Although the most sustainable water supply alternative was recommended through an LCA analysis, multi-water resources should be integrated into the region's water supply from the perspective of water sustainability. The results of this study provide a useful recommendation on the management of water resources for China.

  20. Response of phytoplankton and bacterial biomass during a wastewater effluent diversion into nearshore coastal waters

    Science.gov (United States)

    Caron, David A.; Gellene, Alyssa G.; Smith, Jayme; Seubert, Erica L.; Campbell, Victoria; Sukhatme, Gaurav S.; Seegers, Bridget; Jones, Burton H.; Lie, Alle A. Y.; Terrado, Ramon; Howard, Meredith D. A.; Kudela, Raphael M.; Hayashi, Kendra; Ryan, John; Birch, James; Demir-Hilton, Elif; Yamahara, Kevan; Scholin, Chris; Mengel, Michael; Robertson, George

    2017-02-01

    A 3-week diversion of the Orange County Sanitation District effluent discharge into nearshore waters off Newport Beach, CA constituted a considerable injection of secondarily-treated effluent into the coastal ecosystem. The location ≈1.6 km from shore, shallow water depth (≈16 m), volume and nutrient content of the discharge (≈5.3 × 108 L day-1 of effluent with inorganic nitrogen concentration >2 mM) during the diversion raised concerns regarding the potential for stimulating phytoplankton blooms and, in particular, blooms of toxic species. Remarkably, phytoplankton standing stocks during the event and shortly thereafter did not reach values associated even with minor blooms historically observed in the region (generally algae increased mid-diversion, and cyanobacteria (Synechococcus, Prochlorococcus) increased near the end of the diversion. Concentrations of domoic acid (a phycotoxin commonly present in the area) remained near or below detection throughout the diversion, and abundances of potentially-harmful algal species were unresponsive. Bacterial biomass increased during the diversion, and equaled or exceeded total phytoplankton biomass in most samples. Abundances of microbial grazers were also elevated during the diversion. We speculate that nutrient uptake by the bacterial biomass, acting in concert with or a response to a negative effect of disinfection byproducts associated with chlorination on phytoplankton physiology, played a significant role in muting the response of the phytoplankton to nutrients released in the effluent.

  1. Can complementarity in water use help to explain diversity-productivity relationships in experimental grassland plots?

    Science.gov (United States)

    Verheyen, Kris; Bulteel, Hugo; Palmborg, Cecilia; Olivié, Bert; Nijs, Ivan; Raes, Dirk; Muys, Bart

    2008-05-01

    Positive diversity-productivity relationships have repeatedly been found in experimental grassland plots, but mechanistic explanations are still under debate. We tested whether complementarity for the exploitation of the soil water resource helps to explain these relationships. In the dry summer of 2003, evapotranspiration (ET) was assessed at the Swedish BIODEPTH site using two different approaches: snapshot measurements of canopy surface temperature and simulation of time-accumulated ET by means of a soil water balance model. More diverse plots were characterized by lower surface temperatures and higher accumulated ET. Transgressive overyielding tests revealed that ET in polycultures was higher than in the best-performing monocultures, but this pattern was reversed at high degrees of water stress. Our results indicate that a more complete exploitation of soil water by more diverse grassland systems is on the one hand likely to be a driver for their increased biomass production, but on the other hand causes the more diverse communities to be affected earlier by drought. Nevertheless, the results also suggest that productivity may (at least partially) be maintained under dry conditions due to the higher likelihood of including drought-tolerant species in the more diverse communities.

  2. Diversity and antibiotic resistance of Aeromonas spp. in drinking and waste water treatment plants.

    Science.gov (United States)

    Figueira, Vânia; Vaz-Moreira, Ivone; Silva, Márcia; Manaia, Célia M

    2011-11-01

    The taxonomic diversity and antibiotic resistance phenotypes of aeromonads were examined in samples from drinking and waste water treatment plants (surface, ground and disinfected water in a drinking water treatment plant, and raw and treated waste water) and tap water. Bacteria identification and intra-species variation were determined based on the analysis of the 16S rRNA, gyrB and cpn60 gene sequences. Resistance phenotypes were determined using the disc diffusion method. Aeromonas veronii prevailed in raw surface water, Aeromonas hydrophyla in ozonated water, and Aeromonas media and Aeromonas puntacta in waste water. No aeromonads were detected in ground water, after the chlorination tank or in tap water. Resistance to ceftazidime or meropenem was detected in isolates from the drinking water treatment plant and waste water isolates were intrinsically resistant to nalidixic acid. Most of the times, quinolone resistance was associated with the gyrA mutation in serine 83. The gene qnrS, but not the genes qnrA, B, C, D or qepA, was detected in both surface and waste water isolates. The gene aac(6')-ib-cr was detected in different waste water strains isolated in the presence of ciprofloxacin. Both quinolone resistance genes were detected only in the species A. media. This is the first study tracking antimicrobial resistance in aeromonads in drinking, tap and waste water and the importance of these bacteria as vectors of resistance in aquatic environments is discussed.

  3. Microbial species diversity, community dynamics, and metabolite kinetics of water kefir fermentation.

    Science.gov (United States)

    Laureys, David; De Vuyst, Luc

    2014-04-01

    Water kefir is a sour, alcoholic, and fruity fermented beverage of which the fermentation is started with water kefir grains. These water kefir grains consist of polysaccharide and contain the microorganisms responsible for the water kefir fermentation. In this work, a water kefir fermentation process was followed as a function of time during 192 h to unravel the community dynamics, the species diversity, and the kinetics of substrate consumption and metabolite production. The majority of the water kefir ecosystem was found to be present on the water kefir grains. The most important microbial species present were Lactobacillus casei/paracasei, Lactobacillus harbinensis, Lactobacillus hilgardii, Bifidobacterium psychraerophilum/crudilactis, Saccharomyces cerevisiae, and Dekkera bruxellensis. The microbial species diversities in the water kefir liquor and on the water kefir grains were similar and remained stable during the whole fermentation process. The major substrate, sucrose, was completely converted after 24 h of fermentation, which coincided with the production of the major part of the water kefir grain polysaccharide. The main metabolites of the fermentation were ethanol and lactic acid. Glycerol, acetic acid, and mannitol were produced in low concentrations. The major part of these metabolites was produced during the first 72 h of fermentation, during which the pH decreased from 4.26 to 3.45. The most prevalent volatile aroma compounds were ethyl acetate, isoamyl acetate, ethyl hexanoate, ethyl octanoate, and ethyl decanoate, which might be of significance with respect to the aroma of the end product.

  4. Microbial Species Diversity, Community Dynamics, and Metabolite Kinetics of Water Kefir Fermentation

    Science.gov (United States)

    Laureys, David

    2014-01-01

    Water kefir is a sour, alcoholic, and fruity fermented beverage of which the fermentation is started with water kefir grains. These water kefir grains consist of polysaccharide and contain the microorganisms responsible for the water kefir fermentation. In this work, a water kefir fermentation process was followed as a function of time during 192 h to unravel the community dynamics, the species diversity, and the kinetics of substrate consumption and metabolite production. The majority of the water kefir ecosystem was found to be present on the water kefir grains. The most important microbial species present were Lactobacillus casei/paracasei, Lactobacillus harbinensis, Lactobacillus hilgardii, Bifidobacterium psychraerophilum/crudilactis, Saccharomyces cerevisiae, and Dekkera bruxellensis. The microbial species diversities in the water kefir liquor and on the water kefir grains were similar and remained stable during the whole fermentation process. The major substrate, sucrose, was completely converted after 24 h of fermentation, which coincided with the production of the major part of the water kefir grain polysaccharide. The main metabolites of the fermentation were ethanol and lactic acid. Glycerol, acetic acid, and mannitol were produced in low concentrations. The major part of these metabolites was produced during the first 72 h of fermentation, during which the pH decreased from 4.26 to 3.45. The most prevalent volatile aroma compounds were ethyl acetate, isoamyl acetate, ethyl hexanoate, ethyl octanoate, and ethyl decanoate, which might be of significance with respect to the aroma of the end product. PMID:24532061

  5. Vertical Distribution of Bacterial Community Diversity and Water Quality during the Reservoir Thermal Stratification

    Directory of Open Access Journals (Sweden)

    Hai-Han Zhang

    2015-06-01

    Full Text Available Reservoir thermal stratification drives the water temperature and dissolved oxygen gradient, however, the characteristic of vertical water microbial community during thermal stratification is so far poorly understood. In this work, water bacterial community diversity was determined using the Illumina Miseq sequencing technique. The results showed that epilimnion, metalimnion and hypolimnion were formed steadily in the JINPEN drinking water reservoir. Water temperature decreased steadily from the surface (23.11 °C to the bottom (9.17 °C. Total nitrogen ranged from 1.07 to 2.06 mg/L and nitrate nitrogen ranged from 0.8 to 1.84 mg/L. The dissolved oxygen concentration decreased sharply below 50 m, and reached zero at 65 m. The Miseq sequencing revealed a total of 4127 operational taxonomic units (OTUs with 97% similarity, which were affiliated with 15 phyla including Acidobacteria, Actinobacteria, Armatimonadetes, Bacteroidetes, Caldiserica, Chlamydiae, Chlorobi, Chloroflexi, Cyanobacteria, Firmicutes, Gemmatimonadetes, Nitrospirae, Planctomycetes, Proteobacteria, and Verrucomicrobia. The highest Shannon diversity was 4.41 in 45 m, and the highest Chao 1 diversity was 506 in 5 m. Rhodobacter dominated in 55 m (23.24% and 65 m (12.58%. Prosthecobacter dominated from 0.5 to 50 m. The heat map profile and redundancy analysis (RDA indicated significant difference in vertical water bacterial community composition in the reservoir. Meanwhile, water quality properties including dissolved oxygen, conductivity, nitrate nitrogen and total nitrogen have a dramatic influence on vertical distribution of bacterial communities.

  6. Analysis of the impact of water level fluctuations on macrophytes in Miyun Reservoir after receiving water transferred by the South-to-North Water Diversion Project

    Science.gov (United States)

    Yu, L.; Gu, H.; Lou, C. H.; Zhang, L.; Meng, Q. Y.

    2016-08-01

    As the main primary producers in aquatic ecosystems, macrophytes affect the structure and function of aquatic ecosystems, and their distribution is controlled by water depth. Miyun Reservoir in Beijing will have to experience substantial changes in water level and surface area as it begins to receive water transferred by the South-to-North Water Diversion Project, which will have an adverse impact on the macrophytes growing there. In this study, a hydrodynamic model was constructed with MIKE21 and then used in a simulation in three scenarios: dry year, normal year and wet year. The results suggest that during water diversion, the annual and interannual water level fluctuations will be too significant for them to adapt and as a result, the original macrophytes in the reservoir tend to die and disappear completely. The area of the zone suitable for macrophyte growth, or suitable growth zone (SGZ), fluctuated. Restricted by the main dam and auxiliary dam to its south, the overall suitable growth zone moved toward the northeast and northwest of the reservoir, with a northeastward movement of its centroid. The distance and path of movement varied between scenarios. After the water diversion was completed, the suitable growth zone shrunk in the three scenarios. It is predicted that the macrophyte species diversity and richness of the reservoir can recover to the levels recorded before water diversion only in dry year. These results suggest that manual interventions should be implemented after water diversion to speed up the natural recovery of aquatic plant communities in Miyun Reservoir and thereby maintain the stability of the aquatic ecosystem.

  7. Bacterial diversity in five Icelandic geothermal waters: temperature and sinter growth rate effects.

    Science.gov (United States)

    Tobler, Dominique J; Benning, Liane G

    2011-07-01

    The microbial ecology associated with siliceous sinters was studied in five geochemically diverse Icelandic geothermal systems. Bacterial 16S rRNA clone libraries were constructed from water-saturated precipitates from each site resulting in a total of 342 bacterial clone sequences and 43 species level phylotypes. In near-neutral, saline (2.6-4.7% salinity) geothermal waters where sinter growth varied between 10 and ~300 kg year(-1) m(-2), 16S rRNA gene analyses revealed very low (no OTUs could be detected) to medium (9 OTUs) microbial activity. The most dominant phylotypes found in these waters belong to marine genera of the Proteobacteria. In contrast, in alkaline (pH = 9-10), meteoric geothermal waters with temperature = 66-96°C and geothermal waters; alkaliphilic thermophilic microbial communities with phylotypes related to heterotrophic and autotrophic microorganisms developed in alkaline high temperature waters, whereas halophilic mesophilic communities dominated coastal geothermal waters.

  8. Larval green and white sturgeon swimming performance in relation to water-diversion flows

    OpenAIRE

    Verhille, Christine E.; Poletto, Jamilynn B.; Cocherell, Dennis E.; DeCourten, Bethany; Baird, Sarah; Joseph J Cech; Fangue, Nann A.

    2014-01-01

    Little is known of the swimming capacities of larval sturgeons, despite global population declines in many species due in part to fragmentation of their spawning and rearing habitats by man-made water-diversion structures. Larval green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) inhabit the highly altered Sacramento–San Joaquin watershed, making them logical species to examine vulnerability to entrainment by altered water flows. The risk of larval sturgeon entrainment...

  9. Potential Ecological Benefits of the Middle Route for the South-North Water Diversion Project

    Institute of Scientific and Technical Information of China (English)

    HanChu CHEN; DU Pengfei

    2008-01-01

    This paper presents a study of the middle route of the South-North Water Diversion Project.The middle route runs through the Northern China plain,where the water shortages are the most severe.There is not only a shortage of water for human usage,but also a shortage of ecological water.Although the current plan for the middle route is strictly focused on supplying water for residential and industrial use,the water can also potentially be used for ecological purposes.This paper evaluates the potential ecological benefits that can be brought to the fragile ecology in northern China by the middle route,in addition to the water supplied to residences and industry.The study describes ecological benefits of the middle route project,such as mitigation of groundwater extraction in the region and positive influences on the climate,the ecological uses of the middle route project itself,such as creating artificial niches along the channel and directly using the channel for ecological purposes,and the ecological uses of the water along the middle route,such as diversion of the water into river channels that have suffered from drought conditions for decades.

  10. Prediction in Ungauged Basins (PUB) for estimating water availability during water scarcity conditions: rainfall-runoff modelling of the ungauged diversion inflows to the Ridracoli water supply reservoir

    Science.gov (United States)

    Toth, Elena

    2013-04-01

    The Ridracoli reservoir is the main drinking water supply reservoir serving the whole Romagna region, in Northern Italy. Such water supply system has a crucial role in an area where the different characteristics of the communities to be served, their size, the mass tourism and the presence of food industries highlight strong differences in drinking water needs. Its operation allows high quality drinking water supply to a million resident customers, plus a few millions of tourists during the summer of people and it reduces the need for water pumping from underground sources, and this is particularly important since the coastal area is subject also to subsidence and saline ingression into aquifers. The system experienced water shortage conditions thrice in the last decade, in 2002, in 2007 and in autumn-winter 2011-2012, when the reservoir water storage fell below the attention and the pre-emergency thresholds, thus prompting the implementation of a set of mitigation measures, including limitations to the population's water consumption. The reservoir receives water not only from the headwater catchment, closed at the dam, but also from four diversion watersheds, linked to the reservoir through an underground water channel. Such withdrawals are currently undersized, abstracting only a part of the streamflow exceeding the established minimum flows, due to the design of the water intake structures; it is therefore crucial understanding how the reservoir water availability might be increased through a fuller exploitation of the existing diversion catchment area. Since one of the four diversion catchment is currently ungauged (at least at the fine temporal scale needed for keeping into account the minimum flow requirements downstream of the intakes), the study first presents the set up and parameterisation of a continuous rainfall-runoff model at hourly time-step for the three gauged diversion watersheds and for the headwater catchment: a regional parameterisation

  11. Assessment of the Bacterial Diversity of Aircraft Water: Identification of the Frequent Fliers.

    Science.gov (United States)

    Handschuh, Harald; Ryan, Michael P; O'Dwyer, Jean; Adley, Catherine C

    2017-01-01

    The aim of this study was to determine and identify bacteria inhabiting the supply chain of an airline's drinking water using phenotypic and 16S rDNA sequence-based analysis. Water samples (n = 184) were sourced from long-haul and short-haul aircraft, the airline water source and a water service vehicle. In total, 308 isolates were characterised and their identity determined, which produced 82 identified bacterial species belonging to eight classes: γ-Proteobacteria; β-Proteobacteria; α-Proteobacteria; Bacilli; Actinobacteria; Flavobacteria; Sphingobacteria and Cytophaga. Statistical differences in bacterial diversity were found to exist across sampling locations (X2 = 39.220, p = 0.009) and furthermore, differences were observed (X2 = 15.475, p = 0.030) across aircraft type (long- or short-haul). This study demonstrates the diverse nature of microorganisms within the aircraft drinking water supply chain. To the best of our knowledge, this is the most extensive study undertaken to date of microbial diversity in aircraft drinking water.

  12. Legionella species diversity and dynamics from surface reservoir to tap water: from cold adaptation to thermophily.

    Science.gov (United States)

    Lesnik, René; Brettar, Ingrid; Höfle, Manfred G

    2016-05-01

    Water samples of the Drinking Water Supply System (DWSS) of the city of Braunschweig were analysed for its Legionella species composition using genus-specific PCR amplicons and single-strand conformation polymorphism (SSCP) fingerprint analyses based on 16S rRNA genes. These analyses comprised the whole supply chain including raw water, treatment process and large-scale storage, and a seasonal study of finished drinking water sampled monthly from cold and hot tap water. Treatment of raw water had a major impact on Legionella species by reducing their diversity and abundances. The Legionella species composition of the tap water was highly distinct from that of both source waters. In cold water, 8-14 different phylotypes of Legionella (PTLs) were observed per sample with relative abundances ranging from >1% to 53%. In hot water, L. pneumophila was present during all seasons at high relative abundances (8-40%) accompanied by 5-14 other PTLs of which 6 PTLs were in common with cold water. This thermophilic Legionella community, including L. pneumophila, was able to grow in the hot water above 50 °C. Such thermophilic Legionella populations are of general relevance for drinking water management and public health, but also for the ecology and evolution of the genus Legionella.

  13. Augmenting Species Diversity in Water Quality Criteria Derivation using Interspecies Correlation Models

    Science.gov (United States)

    The specific requirements for taxa diversity of the 1985 guidelines have limited the number of ambient water quality criteria (AWQC) developed for aquatic life protection. The EPA developed the Web-based Interspecies Correlation Estimation (Web-ICE) tool to allow extrapolation of...

  14. Bacterial community diversity and variation in spray water sources and the tomato fruit surface

    Directory of Open Access Journals (Sweden)

    Ottesen Andrea R

    2011-04-01

    Full Text Available Abstract Background Tomato (Solanum lycopersicum consumption has been one of the most common causes of produce-associated salmonellosis in the United States. Contamination may originate from animal waste, insects, soil or water. Current guidelines for fresh tomato production recommend the use of potable water for applications coming in direct contact with the fruit, but due to high demand, water from other sources is frequently used. We sought to describe the overall bacterial diversity on the surface of tomato fruit and the effect of two different water sources (ground and surface water when used for direct crop applications by generating a 454-pyrosequencing 16S rRNA dataset of these different environments. This study represents the first in depth characterization of bacterial communities in the tomato fruit surface and the water sources commonly used in commercial vegetable production. Results The two water sources tested had a significantly different bacterial composition. Proteobacteria was predominant in groundwater samples, whereas in the significantly more diverse surface water, abundant phyla also included Firmicutes, Actinobacteria and Verrucomicrobia. The fruit surface bacterial communities on tomatoes sprayed with both water sources could not be differentiated using various statistical methods. Both fruit surface environments had a high representation of Gammaproteobacteria, and within this class the genera Pantoea and Enterobacter were the most abundant. Conclusions Despite the major differences observed in the bacterial composition of ground and surface water, the season long use of these very different water sources did not have a significant impact on the bacterial composition of the tomato fruit surface. This study has provided the first next-generation sequencing database describing the bacterial communities living in the fruit surface of a tomato crop under two different spray water regimes, and therefore represents an

  15. Maintaining healthy rivers and lakes through water diversion from Yangtze River to Taihu lake in Taihu Basin

    Directory of Open Access Journals (Sweden)

    Hao-yun WU

    2008-09-01

    Full Text Available On the basis of the Taihu water resources assessment, an analysis of the importance and rationality of the water diversion from the Yangtze River to Taihu Lake in solving the water problem and establishing a harmonious eco-environment in the Taihu Basin is performed. The water quantity and water quality conjunctive dispatching decision-making support system, which ensures flood control, water supply and eco-aimed dispatching, is built by combining the water diversion with flood control dispatching and strengthening water resources monitoring and forecasting. With the practice and effect assessment, measures such as setting the integrated basin management format, further developing water diversion and improving the hydraulic engineering projects system and water monitoring system are proposed in order to maintain healthy rivers and guarantee the development of the economy and society in the Taihu Basin.

  16. Characterization of the microbial diversity in production waters of mesothermic and geothermic Tunisian oilfields.

    Science.gov (United States)

    Mnif, Sami; Bru-Adan, Valérie; Godon, Jean-Jacques; Sayadi, Sami; Chamkha, Mohamed

    2013-01-01

    The microbial diversity of production waters of five Tunisian oilfields was investigated using Single Strand Conformation Polymorphism (SSCP) technique followed by cloning-sequencing. Dynamics of bacterial populations in production waters collected from four wellheads were also evaluated. For all production water samples collected, DNA from Archaea and Eucarya was not sufficiently abundant to permit detection rRNA genes from these groups by PCR-SSCP. In contrast, the bacterial rRNA genes were detected in all samples, except for samples from DOULEB12 and RAMOURA wells. SSCP profiles attested that two of the studied geothermic wells (ASHTART47 and ASHTART48) had shown a clear change over time, whereas a stable diversity was found with the mesophilic DOULEB well (DL3). PCR amplification of rRNA genes was unsuccessful with samples from DOULEB (DL12) at all three sampling time. The bacterial diversity present in production waters collected from pipelines of SERCINA and LITAYEM oilfields was high, while production waters collected from wellheads (ASHTART and DOULEB) exhibited lower diversity. The partial study of the biodiversity showed a dominance of uncultured bacteria and Pseudomonas genus (class of the Gammaproteobacteria) in three of the studied oilfields (ASHTART47, ASHTART48 and DOULEB3). However, for LITAYEM oilfield, a significant dominance of 5 phyla (Proteobacteria, Thermotogae, Firmicutes, Synergistetes, Bacteroidetes) was shown. Our study gives a real picture of the microbiology of some Tunisian oilfield production waters and shows that some of the sequenced bacterial clones have a great similarity to previous sequenced clones described from other oilfields all over the world, indicating that these ecosystems harbour specific microbial communities. These findings can be considered as an indirect indication of the indigenous origin of these clones.

  17. Optimization and coordination of South-to-North Water Diversion supply chain with strategic customer behavior

    Directory of Open Access Journals (Sweden)

    Zhi-song CHEN

    2012-12-01

    Full Text Available The South-to-North Water Diversion (SNWD Project is a significant engineering project meant to solve water shortage problems in North China. Faced with market operations management of the water diversion system, this study defined the supply chain system for the SNWD Project, considering the actual project conditions, built a decentralized decision model and a centralized decision model with strategic customer behavior (SCB using a floating pricing mechanism (FPM, and constructed a coordination mechanism via a revenue-sharing contract. The results suggest the following: (1 owing to water shortage supplements and the excess water sale policy provided by the FPM, the optimal ordering quantity of water resources is less than that without the FPM, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without the FPM; (2 wholesale pricing and supplementary wholesale pricing with SCB are higher than those without SCB, and the optimal profits of the whole supply chain, supplier, and external distributor are higher than they would be without SCB; and (3 considering SCB and introducing the FPM help increase the optimal profits of the whole supply chain, supplier, and external distributor, and improve the efficiency of water resources usage.

  18. Spatiotemporal heterogeneity of phytoplankton diversity and its relation to water environmental factors in the southern waters of Miaodao Archipelago, China

    Institute of Scientific and Technical Information of China (English)

    ZHENG Wei; LI Fen; SHI Honghua; HUO Yuanzi; LI Yan; CHI Yuan; GUO Zhen

    2016-01-01

    To study the water quality influenced by the anthropogenic activities and its impact on the phytoplankton diversity in the surface waters of Miaodao Archipelago, the spatiotemporal variations in phytoplankton communities and the environmental properties of the surface waters surrounding the Five Southern Islands of Miaodao Archipelago were investigated, based on seasonal field survey conducted from November 2012 to August 2013. During the survey, a total of 109 phytoplankton species from 3 groups were identified in the southern waters of Miaodao Archipelago, of which 77 were diatoms, 29 were dinoflagellates, and 3 were chrysophytes. Species number was higher in winter (73), moderate in autumn (70), but lower in summer (31) and spring (27). The species richness index in autumn (5.92) and winter (4.28) was higher than that in summer (2.83) and spring (1.41). The Shannon-Wiener diversity index was high in autumn (2.82), followed by winter (1.99) and summer (1.92), and low in spring (0.07). The species evenness index in autumn (0.46) and summer (0.39) was higher than that in winter (0.32) and spring (0.02). On the basis of principal component analysis (PCA) and redundancy analysis (RDA), we found that dissolved inorganic nitrogen (DIN) and chemical oxygen demand (COD) in spring, COD in summer, pH in autumn, and salinity and oil pollutant in winter, respectively, showed the strongest association with the distribution of phytoplankton diversity. The spatial heterogeneity of the southern waters of Miaodao Archipelago was quite obvious, and three zones, i.e., northeastern, southwestern and inter-island water area, were identified by cluster analysis (CA) based on key environmental variables.

  19. Application of PCR-DGGE in Research of Bacterial Diversity in Drinking Water

    Institute of Scientific and Technical Information of China (English)

    QING WU; XIN-HUA ZHAO; SHENG-YUE ZHAO

    2006-01-01

    Objective To analyze the structure of bacteria in drinking water by molecular biological techniques. Methods DNA of bacteria in drinking water was directly extracted without culture. 16S ribosomal DNA fragments, including V-6, -7, and -8regions, were amplified with universal primers (EUBf933GC and EUBr1387) and analyzed by DGGE. Results DGGE indicated that amplification products could be separated. The results showed that DGGE could be used in the separation of different microbial 16SrRNA genes extracted from drinking water. Though there were special bacteria in different water samples, the predominant bacteria were essentially the same. Three sequences of the reclaimed specific bands were obtained, and phylogenetic tree of these bands was made. Conclusion Bacterial diversity in drinking water is identified by molecular biological techniques.

  20. Maintaining healthy rivers and lakes through water diversion from Yangtze River to Taihu Lake in Taihu Basin

    Institute of Scientific and Technical Information of China (English)

    Wu Haoyun; Hu Yan

    2008-01-01

    On the basis of the Taihu water resources assessment, an analysis of the importance and rationality of the water diversion from the Yangtze River to Taihu Lake in solving the water problem and establishing a harmonious eco-environment in the Taihu Basin is performed. The water quantity and watcr quality conjunctive dispatching decision-making support system, which ensures flood control, water supply and eco-aimed dispatching, is built by combining the water diversion with flood control dispatching and strengthening water resources monitoring and forecasting. With the practice and effect assessment, measures such as setting the integrated basin management format, further developing water diversion and improving the hydraulic engineering projects system and water monitoring system are proposed in order to maintain healthy rivers and guarantee the development of the economy and society in the Taihu Basin.

  1. [Correlative analysis of the diversity patterns of regional surface water, NDVI and thermal environment].

    Science.gov (United States)

    Duan, Jin-Long; Zhang, Xue-Lei

    2012-10-01

    Taking Zhengzhou City, the capital of Henan Province in Central China, as the study area, and by using the theories and methodologies of diversity, a discreteness evaluation on the regional surface water, normalized difference vegetation index (NDVI), and land surface temperature (LST) distribution was conducted in a 2 km x 2 km grid scale. Both the NDVI and the LST were divided into 4 levels, their spatial distribution diversity indices were calculated, and their connections were explored. The results showed that it was of operability and practical significance to use the theories and methodologies of diversity in the discreteness evaluation of the spatial distribution of regional thermal environment. There was a higher overlap of location between the distributions of surface water and the lowest temperature region, and the high vegetation coverage was often accompanied by low land surface temperature. In 1988-2009, the discreteness of the surface water distribution in the City had an obvious decreasing trend. The discreteness of the surface water distribution had a close correlation with the discreteness of the temperature region distribution, while the discreteness of the NDVI classification distribution had a more complicated correlation with the discreteness of the temperature region distribution. Therefore, more environmental factors were needed to be included for a better evaluation.

  2. Bacterial diversity and antibiotic resistance in water habitats: searching the links with the human microbiome.

    Science.gov (United States)

    Vaz-Moreira, Ivone; Nunes, Olga C; Manaia, Célia M

    2014-07-01

    Water is one of the most important bacterial habitats on Earth. As such, water represents also a major way of dissemination of bacteria between different environmental compartments. Human activities led to the creation of the so-called urban water cycle, comprising different sectors (waste, surface, drinking water), among which bacteria can hypothetically be exchanged. Therefore, bacteria can be mobilized between unclean water habitats (e.g. wastewater) and clean or pristine water environments (e.g. disinfected and spring drinking water) and eventually reach humans. In addition, bacteria can also transfer mobile genetic elements between different water types, other environments (e.g. soil) and humans. These processes may involve antibiotic resistant bacteria and antibiotic resistance genes. In this review, the hypothesis that some bacteria may share different water compartments and be also hosted by humans is discussed based on the comparison of the bacterial diversity in different types of water and with the human-associated microbiome. The role of such bacteria as potential disseminators of antibiotic resistance and the inference that currently only a small fraction of the clinically relevant antibiotic resistome may be known is discussed.

  3. Hydrochemical diversity of semi-natural water system on the background of environmental conditions.

    Science.gov (United States)

    Cudowski, Adam; Górniak, Andrzej Stefan; Więcko, Adam

    2015-06-01

    Research carried out from 2007 to 2011 showed that a tested semi-natural water system with a diverse catchment (peat, peat-mineral and mineral) has a very varied quality of water, as evidenced by a the large range of conductivity (174-828 μS/cm) and pH (6.34-9.92). Natural lake parts of the semi-natural water system were similar to the artificial parts in terms of physico-chemical parameters, as evidenced by the lack of statistically significant differences between the water quality in both of these ecosystems. Taking into account the quality of various types of water in this semi-natural system, it can be seen that the river waters differed significantly (p system contributed to higher values of many tested parameters (EC, pH, TC, TN, SO4 (2-) or Cl(-)) in waters of the canal. In contrast, rivers with high values of concentrations of organic matter (TOC > 10.0 mg/L) contributed to a decline in values of those parameters. Moreover, lake waters within the tested semi-natural water system showed a "cleansing" function, because they caused a decrease in conductivity, pH or the concentration of carbon, total nitrogen, sulphate(VI) and chloride in waters of the canal.

  4. Sequence types diversity of Legionella pneumophila isolates from environmental water sources in Guangzhou and Jiangmen, China.

    Science.gov (United States)

    Guo, Jingyu; Liang, Ting; Hu, Chaohui; Lv, Ruichen; Yang, Xianwei; Cui, Yujun; Song, Youtao; Yang, Ruifu; Zhu, Qingyi; Song, Yajun

    2015-01-01

    In this study, 159 Legionella pneumophila strains isolated from various natural and artificial water sources in Guangzhou and Jiangmen, China, were subjected to genotyping by the sequence-based typing (SBT) scheme. These isolates were assigned into 53 sequence types (STs) (50 STs with seven loci data and three unidentified STs with incomplete loci profiles) with ST1 as the dominant one (14.5%), and the index of diversity (IOD) was 0.950. Eight new alleles and 34 new STs were reported here. Notably, most of the newly identified STs with seven loci data (24/34) contained no new allele, implying frequent recombination events in L. pneumophila. Five intragenic recombination events were identified in the concatenated sequences of seven loci. The diversity of STs in natural environmental isolates (41 STs, IOD=0.956) is higher than that of artificial environmental ones (17 STs, IOD=0.824). The ST patterns varied in isolates from these two sources: the most common STs from artificial water sources, ST1 and ST752 (39.2% and 13.7%), were only occasionally isolated from natural water sources (2.9% and 3.8%, respectively); while the predominant STs from natural water sources, ST1048, ST739 and ST1267 (15.2%, 6.7% and 6.7%), were less frequently seen in artificial environments (2.0%, 0% and 0%, respectively). We also found out that Legionnaires' disease associated STs might be more frequently isolated in artificial environments than in natural ones. Our data revealed remarkable genetic diversity of L. pneumophila isolates from environmental water systems of Guangzhou and Jiangmen, and the different ST distribution patterns between natural water and artificial water sources as well.

  5. Discharge capacity of sluiceway channel of water intake structure for diversion power plant in winter

    Directory of Open Access Journals (Sweden)

    N.P. Lavrov

    2013-06-01

    Full Text Available The paper presents results of research hydraulic processes at the intake structures of diversion power plants in winter. On the basis of the physical modeling results the flow characteristics of sluiceway channel of water intake on the river Issyk-Ata, Kyrgyzstan were determined. Statistical models of discharges of elements of sluiceway channel with their mutual influence were obtained, using the methods of experimental design and data analysis. The influence of the concentration of brash ice on the sluiceway channel and its elements is described. The comparison of experimental data with data obtained by other authors before is made by comparing flow coefficients. Recommendations for normal operation of ice pass at sluiceway track channel of water intake structure for diversion power plant are given.

  6. Nitrogenase genes in non-cyanobacterial plankton: prevalence, diversity, and regulation in marine waters

    DEFF Research Database (Denmark)

    Riemann, Lasse; Farnelid, H.; Steward, G.F.

    2010-01-01

    -cyanobacterial diazotrophs are diverse, widely distributed, and actively expressing the nitrogenase gene in marine and estuarine environments. The detection of nifH genes and nifH transcripts, even in N-replete marine waters, suggests that N2 fixation is an ecologically important process throughout the oceans. Because...... and expression of nifH genes in non-Cyanobacteria suggests that further study of the role of these Bacteria in N cycling at local, regional and global scales is needed....

  7. Bacterial diversity in five Icelandic geothermal waters: temperature and sinter growth rate effects

    OpenAIRE

    D.J. Tobler; Liane G. Benning

    2011-01-01

    The microbial ecology associated with siliceous sinters was studied in five geochemically diverse Icelandic geothermal systems. Bacterial 16S rRNA clone libraries were constructed from water-saturated precipitates from each site resulting in a total of 342 bacterial clone sequences and 43 species level phylotypes. In near-neutral, saline (2.6-4.7% salinity) geothermal waters where sinter growth varied between 10 and similar to 300 kg year(-1) m(-2), 16S rRNA gene analyses revealed very low (n...

  8. Species Diversity of Shallow Water Zoanthids (Cnidaria: Anthozoa: Hexacorallia in Florida

    Directory of Open Access Journals (Sweden)

    James Davis Reimer

    2012-01-01

    Full Text Available Shallow water zooxanthellate zoanthids are a common component of the coral reef ecosystems of the Caribbean. Despite this, their species diversity remains poorly understood. In this study, collected Palythoa, Zoanthus, Isaurus, and Terrazoanthus specimens from the waters of Florida were phylogenetically examined to obtain a better understanding of zoanthid species diversity in the Caribbean. Surprisingly, the results from analyses utilizing three DNA markers (mitochondrial 16S ribosomal DNA, cytochrome oxidase subunit I, and the internal transcribed spacer of ribosomal DNA showed the presence of at least eleven species, of which up to four appear undescribed. Additionally, the presence of the genus Terrazoanthus in the Caribbean was confirmed for the first time. Attempts to match phylogenetic species or clades with original literature were hampered by vague and short original descriptions, and it is clear that for Atlantic Palythoa and Zoanthus species an in-depth and multidisciplinary investigation is needed to reconcile recent phylogenetic results such as in this study with traditional taxonomy. Furthermore, most shallow water zoanthid species from Florida were observed to have close, sister-species relationships with previously investigated species in the Pacific Ocean. These results indicate that many brachycnemic zoanthid species likely had a Caribbean-Pacific distribution until the formation of the Isthmus of Panama. However, due to inadvertent redescriptions, overall species diversity in these two common genera is likely much lower than literature indicates.

  9. Yeast diversity associated to sediments and water from two Colombian artificial lakes

    Directory of Open Access Journals (Sweden)

    L.M. Silva-Bedoya

    2014-01-01

    Full Text Available In Colombia, knowledge of the yeast and yeast-like fungi community is limited because most studies have focused on species with clinical importance. Sediments and water represent important habitats for the study of yeast diversity, especially for yeast species with industrial, biotechnological, and bioremediation potential. The main purpose of this study was to identify and compare the diversity of yeast species associated with sediment and water samples from two artificial lakes in Universidad del Valle (Cali-Colombia. Yeast samplings were performed from fifteen sediment samples and ten water samples. Grouping of similar isolates was initially based on colony and cell morphology, which was then complemented by micro/mini satellite primed PCR banding pattern analysis by using GTG5 as single primer. A representative isolate for each group established was chosen for D1/D2 domain sequencing and identification. In general, the following yeast species were identified: Candida albicans, Candida diversa, Candida glabrata, Candida pseudolambica, Cryptococcus podzolicus, Cryptococcus rajasthanensis, Cryptococcus laurentii, Williopsis saturnus, Hanseniaspora thailandica, Hanseniaspora uvarum, Rhodotorula mucilaginosa, Saccharomyces cerevisiae, Torulaspora delbrueckii, Torulaspora pretoriensis, Tricosporon jirovecii, Trichosporon laibachii and Yarrowia lypolitica. Two possible new species were also found, belonging to the Issatchenkia sp. and Bullera sp. genera. In conclusion, the lakes at the Universidad del Valle campus have significant differences in yeast diversity and species composition between them.

  10. Impact of water diversion on the morphological development of the Lower Yellow River

    Institute of Scientific and Technical Information of China (English)

    Zhengbing WANG; Zhaoyin WANG; Huib J.de VRIEND

    2008-01-01

    In this paper we carry out a theoretical analysis based on the general one-dimensional morphodynamic model for rivers in order to show how the morphological equilibrium of a river is influenced by water and sediment diversion/supply along the river.The results of the analysis show that large scale water diversions,like those along the Lower Yellow River,can cause the development of a convex riverbed profile in the long-term.Deposition will take place along the whole reach of the river,with an increasing deposition depth from downstream to upstream.The slope of the river bed increases from upstream to downstream.Furthermore.an analysis on the morphological time scale shows that this development in the Lower Yellow River will take a time period on the order of decades to centuries.The results of the anaiysis have been compared with observations in the Lower Yellow River.Since the second half of the 1980's large scale water diversions from the Yellow River have been taking place.The observations show that this has indeed led to significant sedimentation along the river.

  11. Impacts of surface water diversions for marijuana cultivation on aquatic habitat in four northwestern California watersheds.

    Directory of Open Access Journals (Sweden)

    Scott Bauer

    Full Text Available Marijuana (Cannabis sativa L. cultivation has proliferated in northwestern California since at least the mid-1990s. The environmental impacts associated with marijuana cultivation appear substantial, yet have been difficult to quantify, in part because cultivation is clandestine and often occurs on private property. To evaluate the impacts of water diversions at a watershed scale, we interpreted high-resolution aerial imagery to estimate the number of marijuana plants being cultivated in four watersheds in northwestern California, USA. Low-altitude aircraft flights and search warrants executed with law enforcement at cultivation sites in the region helped to validate assumptions used in aerial imagery interpretation. We estimated the water demand of marijuana irrigation and the potential effects water diversions could have on stream flow in the study watersheds. Our results indicate that water demand for marijuana cultivation has the potential to divert substantial portions of streamflow in the study watersheds, with an estimated flow reduction of up to 23% of the annual seven-day low flow in the least impacted of the study watersheds. Estimates from the other study watersheds indicate that water demand for marijuana cultivation exceeds streamflow during the low-flow period. In the most impacted study watersheds, diminished streamflow is likely to have lethal or sub-lethal effects on state- and federally-listed salmon and steelhead trout and to cause further decline of sensitive amphibian species.

  12. Diversity of Salmonella in biofilms and water in a headwater ecosystem.

    Science.gov (United States)

    Sha, Qiong; Forstner, Michael R J; Hahn, Dittmar

    2013-03-01

    The diversity of Salmonella was analysed in biofilm and water samples from the spring and slough arms of Spring Lake, the headwaters of the San Marcos River, Texas, during the drought of 2011, with only one potential run-off event at the beginning of the study. Salmonellae were detected in semiselective enrichment cultures by end-point PCR during the entire sampling period of (11 sampling events during 2 months). From the spring arm site, 73% of the biofilms and 41% of the water samples were positive for salmonellae, while only 9% of the biofilms and 23% of the water samples were positive from the slough arm site. Salmonellae could be isolated from all positive samples, with higher diversity in biofilms compared with water samples and more strains obtained from the spring arm than from the slough arm. Differences between sites were generally caused by less frequently detected isolates, while the majority of isolates that were present in both biofilms and water from both sites was represented by three strains only. Quantification attempts by quantitative PCR directly in samples without prior enrichment did not result in a reliable detection of salmonellae, suggesting that numbers in all samples were below the detection limit.

  13. The degradation behaviour of nine diverse contaminants in urban surface water and wastewater prior to water treatment.

    Science.gov (United States)

    Cormier, Guillaume; Barbeau, Benoit; Arp, Hans Peter H; Sauvé, Sébastien

    2015-12-01

    An increasing diversity of emerging contaminants are entering urban surface water and wastewater, posing unknown risks for the environment. One of the main contemporary challenges in ensuring water quality is to design efficient strategies for minimizing such risks. As a first step in such strategies, it is important to establish the fate and degradation behavior of contaminants prior to any engineered secondary water treatment. Such information is relevant for assessing treatment solutions by simple storage, or to assess the impacts of contaminant spreading in the absence of water treatment, such as during times of flooding or in areas of poor infrastructure. Therefore in this study we examined the degradation behavior of a broad array of water contaminants in actual urban surface water and wastewater, in the presence and absence of naturally occurring bacteria and at two temperatures. The chemicals included caffeine, sulfamethoxazole, carbamazepine, atrazine, 17β-estradiol, ethinylestradiol, diclofenac, desethylatrazine and norethindrone. Little information on the degradation behavior of these pollutants in actual influent wastewater exist, nor in general in water for desethylatrazine (a transformation product of atrazine) and the synthetic hormone norethindrone. Investigations were done in aerobic conditions, in the absence of sunlight. The results suggest that all chemicals except estradiol are stable in urban surface water, and in waste water neither abiotic nor biological degradation in the absence of sunlight contribute significantly to the disappearance of desethylatrazine, atrazine, carbamazepine and diclofenac. Biological degradation in wastewater was effective at transforming norethindrone, 17β-estradiol, ethinylestradiol, caffeine and sulfamethoxazole, with measured degradation rate constants k and half-lives ranging respectively from 0.0082-0.52 d(-1) and 1.3-85 days. The obtained degradation data generally followed a pseudo-first-order-kinetic model

  14. Larval green and white sturgeon swimming performance in relation to water-diversion flows.

    Science.gov (United States)

    Verhille, Christine E; Poletto, Jamilynn B; Cocherell, Dennis E; DeCourten, Bethany; Baird, Sarah; Cech, Joseph J; Fangue, Nann A

    2014-01-01

    Little is known of the swimming capacities of larval sturgeons, despite global population declines in many species due in part to fragmentation of their spawning and rearing habitats by man-made water-diversion structures. Larval green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) inhabit the highly altered Sacramento-San Joaquin watershed, making them logical species to examine vulnerability to entrainment by altered water flows. The risk of larval sturgeon entrainment is influenced by the ontogeny of swimming capacity and dispersal timing and their interactions with water-diversion structure operations. Therefore, the aim of this study was to describe and compare the ontogeny and allometry of larval green and white sturgeon swimming capacities until completion of metamorphosis into juveniles. Despite the faster growth rates and eventual larger size of larval white sturgeon, green sturgeon critical swimming velocities remained consistently, though modestly, greater than those of white sturgeon throughout the larval life stage. Although behavioural interactions with water-diversion structures are also important considerations, regarding swimming capacity, Sacramento-San Joaquin sturgeons are most vulnerable to entrainment in February-May, when white sturgeon early larvae are in the middle Sacramento River, and April-May, when green sturgeon early larvae are in the upper river. Green sturgeon migrating downstream to the estuary and bays in October-November are also susceptible to entrainment due to their movements combined with seasonal declines in their swimming capacity. An additional inter-species comparison of the allometric relationship between critical swimming velocities and total length with several sturgeon species found throughout the world suggests a similar ontogeny of swimming capacity with growth. Therefore, although dispersal and behaviour differ among river systems and sturgeon species, similar recommendations are applicable

  15. Larval green and white sturgeon swimming performance in relation to water-diversion flows

    Science.gov (United States)

    Verhille, Christine E.; Poletto, Jamilynn B.; Cocherell, Dennis E.; DeCourten, Bethany; Baird, Sarah; Cech, Joseph J.; Fangue, Nann A.

    2014-01-01

    Little is known of the swimming capacities of larval sturgeons, despite global population declines in many species due in part to fragmentation of their spawning and rearing habitats by man-made water-diversion structures. Larval green (Acipenser medirostris) and white sturgeon (Acipenser transmontanus) inhabit the highly altered Sacramento–San Joaquin watershed, making them logical species to examine vulnerability to entrainment by altered water flows. The risk of larval sturgeon entrainment is influenced by the ontogeny of swimming capacity and dispersal timing and their interactions with water-diversion structure operations. Therefore, the aim of this study was to describe and compare the ontogeny and allometry of larval green and white sturgeon swimming capacities until completion of metamorphosis into juveniles. Despite the faster growth rates and eventual larger size of larval white sturgeon, green sturgeon critical swimming velocities remained consistently, though modestly, greater than those of white sturgeon throughout the larval life stage. Although behavioural interactions with water-diversion structures are also important considerations, regarding swimming capacity, Sacramento–San Joaquin sturgeons are most vulnerable to entrainment in February–May, when white sturgeon early larvae are in the middle Sacramento River, and April–May, when green sturgeon early larvae are in the upper river. Green sturgeon migrating downstream to the estuary and bays in October–November are also susceptible to entrainment due to their movements combined with seasonal declines in their swimming capacity. An additional inter-species comparison of the allometric relationship between critical swimming velocities and total length with several sturgeon species found throughout the world suggests a similar ontogeny of swimming capacity with growth. Therefore, although dispersal and behaviour differ among river systems and sturgeon species, similar recommendations are

  16. Wind and sunlight shape microbial diversity in surface waters of the North Pacific Subtropical Gyre

    Science.gov (United States)

    Bryant, Jessica A; Aylward, Frank O; Eppley, John M; Karl, David M; Church, Matthew J; DeLong, Edward F

    2016-01-01

    Few microbial time-series studies have been conducted in open ocean habitats having low seasonal variability such as the North Pacific Subtropical Gyre (NPSG), where surface waters experience comparatively mild seasonal variation. To better describe microbial seasonal variability in this habitat, we analyzed rRNA amplicon and shotgun metagenomic data over two years at the Hawaii Ocean Time-series Station ALOHA. We postulated that this relatively stable habitat might reveal different environmental factors that influence planktonic microbial community diversity than those previously observed in more seasonally dynamic habitats. Unexpectedly, the data showed that microbial diversity at 25 m was positively correlated with average wind speed 3 to 10 days prior to sampling. In addition, microbial community composition at 25 m exhibited significant correlations with solar irradiance. Many bacterial groups whose relative abundances varied with solar radiation corresponded to taxa known to exhibit strong seasonality in other oceanic regions. Network co-correlation analysis of 25 m communities showed seasonal transitions in composition, and distinct successional cohorts of co-occurring phylogenetic groups. Similar network analyses of metagenomic data also indicated distinct seasonality in genes originating from cyanophage, and several bacterial clades including SAR116 and SAR324. At 500 m, microbial community diversity and composition did not vary significantly with any measured environmental parameters. The minimal seasonal variability in the NPSG facilitated detection of more subtle environmental influences, such as episodic wind variation, on surface water microbial diversity. Community composition in NPSG surface waters varied in response to solar irradiance, but less dramatically than reported in other ocean provinces. PMID:26645474

  17. The diversity and distribution of Holothuroidea in shallow waters of Baluran National Park, Indonesia

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    ARIF MOHAMMAD SIDDIQ

    2016-04-01

    Full Text Available Abstract. Siddiq AM, Atmowidi T, Qayim I. 2015. The diversity and distribution of Holothuroidea in shallow waters of Baluran National Park, Indonesia. Biodiversitas 17: 55-60. A study of the diversity and distribution of sea cucumber (Holothuroidea in shallow waters at Baluran National Park, East Java, Indonesia was carried out from July until September 2015. The method used in this study was systematic transect in low tide condition. Samples were collected by hands at intertidal sites. Identification of sea cucumber species based on morphological ossicles. Twenty one species of Holothuroidea belonging two orders and four families were found in this study. The most dominant family found was Holothuriidae (16 species, followed by Stichopodidae (2 species, Synaptidae (2 species, and Chiridotidae (1 spesies. Four species (Holothuria olivacea, H. verrucosa, Labidodemas rugosum, and Chiridota smirnovi are new record for Java waters and one species (H. papillifera is a new record for Indonesian waters. Two morphospecies (H. aff. macroperona and Stichopus cf. monotuberculatus need reconfirmation to species level. The highest abundance species of Holothuroidea was found at under rock with 15 species. Whereas, the highest number of individuals was found in seagrass areas with 5457 individuals. H. atra has extensive habitat distribution, such as seagrass, macroalgae, coral reef, dead coral, sand, and under rock.

  18. Mineralogical Diversity in Lake Pavin: Connections with Water Column Chemistry and Biomineralization Processes

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    Jennyfer Miot

    2016-03-01

    Full Text Available As biominerals are good tracers of microbial interactions with the environment, they may provide signatures of microbial evolution and paleoenvironmental conditions. Since modern analogues of past environments help with defining proxies and biosignatures, we explored microbe mineral interactions in the water column of a maar lake, located in France: Lake Pavin. This lake is considered as a potential Precambrian ocean analogue, as it is ferruginous and meromictic, i.e., stratified with a superficial O2-rich layer (mixolimnion and a deeper permanently anoxic layer (monimolimnion. We combined bulk chemical analyses of dissolved and particulate matter in combination with electron microscopy analyses of the particulate matter at different depths along the water column. The mineralogy changed along with water chemistry, and most of the minerals were intimately associated with microorganisms. Evolution of the redox conditions with depth leads to the successive precipitation of silica and carbonates, Mn-bearing, Fe-bearing and S-containing phases, with a predominance of phosphates in the monimolimnion. This scheme parallels the currently-assessed changes of microbial diversity with depth. The present results corroborate previous studies that suggested a strong influence of microbial activity on mineralogical diversity through extracellular and intracellular biomineralization. This paper reports detailed data on mineralogical profiles of the water column and encourages extended investigation of these processes.

  19. Modelling water quality and quantity with the influence of inter-basin water diversion projects and cascade reservoirs in the Middle-lower Hanjiang River

    Science.gov (United States)

    Wang, Yonggui; Zhang, Wanshun; Zhao, Yanxin; Peng, Hong; Shi, Yingyuan

    2016-10-01

    The effects of inter-basin water diversion projects and cascade reservoirs are typically complex and challenging, as the uncertain temporal-spatial variation of both water quality and quantity. The purpose of this paper is to propose a coupled 1D hydrodynamic model with water-quality model to analyze the effects of current and future inter-basin water diversion projects, i.e., South-to-North Water Diversion Project (SNWD) and Yangtze-Hanjiang Water Diversion Project (YHWD), and cascade reservoirs (CRS) on water quantity and quality in the middle-lower Hanjiang River. Considering water use and pollution contribution, the middle-lower Hanjaing River basin is generalized and divided into 18 land use units with tributaries, reservoirs and water exchanges. Each unit is considered with the processes of lateral inflow, point and non-point pollution loads, irrigation return flow, and stream-aquifer exchanges in the model. The long-term time series from 1956 to 1998 of water quality and quantity with four engineering scenarios is collected. The validation of results shows that the relative errors between the simulated and observed values at certain control sections are within 5% for water levels and 20% for water quality. The water level will be decreased by 0.38-0.65 m (decreasing rate 0.44-2.68%), the annual runoff will be significantly decreased over 4 billion m3 and the water quality will be changed after the SNWD. As a compensation project, the YHWD partly offsets the negative effects of the SNWD in water flow rate, but at the same time it rises the water level and reduces the flow velocity. This, together with the effect of cascade reservoirs, leads to water quality concentration increasing and deteriorating to Grade IV of the Chinese Surface Water Quality Criteria. The water resource reduction and water quality problems in the Middle-lower Hanjiang River require attention after these projects.

  20. Modeling terrestrial carbon and water dynamics across climatic gradients: does plant trait diversity matter?

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    Pappas, Christoforos; Fatichi, Simone; Burlando, Paolo

    2016-01-01

    Plant trait diversity in many vegetation models is crudely represented using a discrete classification of a handful of 'plant types' (named plant functional types; PFTs). The parameterization of PFTs reflects mean properties of observed plant traits over broad categories ignoring most of the inter- and intraspecific plant trait variability. Taking advantage of a multivariate leaf-trait distribution (leaf economics spectrum), as well as documented plant drought strategies, we generate an ensemble of hypothetical species with coordinated attributes, rather than using few PFTs. The behavior of these proxy species is tested using a mechanistic ecohydrological model that translates plant traits into plant performance. Simulations are carried out for a range of climates representative of different elevations and wetness conditions in the European Alps. Using this framework we investigate the sensitivity of ecosystem response to plant trait diversity and compare it with the sensitivity to climate variability. Plant trait diversity leads to highly divergent vegetation carbon dynamics (fluxes and pools) and to a lesser extent water fluxes (transpiration). Abiotic variables, such as soil water content and evaporation, are only marginally affected. These results highlight the need for revising the representation of plant attributes in vegetation models. Probabilistic approaches, based on observed multivariate whole-plant trait distributions, provide a viable alternative.

  1. Diversity and Distribution of Freshwater Fishes in Aceh Water, Northern-Sumatra,Indonesia

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    M.N. Siti Azizah

    2009-01-01

    Full Text Available The objective of the present study was to evaluate the diversity of freshwater fish and its distribution and to establish an inventory of the freshwater fish fauna in Aceh water. Sampling was done in five regions of NAD at 17 sites. Explorative research was conducted from January to June 2008 by investigating rivers based on information by local residents. Sampling was carried out in both lotic and lentic ecosystems. A total of 711 fishes belonging to 114 species, 69 genera, 41 families and 12 orders. Five families were distributed widely and observed in all the five regions i.e., Anguillidae, Clariidae, Cyprinidae, Anabantidae and Channidae. Sixteen families were found in only a single site. The diversity index of fishes in Aceh water ranged from 1.31 to 3.41 with an average of 2.17 indicating moderate values. The highest diversity was found in Lembang River of Aceh Selatan, while regionally, the North and south regions were higher but not significantly different from the West region. Highest similarity was found between Simpang dam and Sibreh irrigation canal of Sibreh. The similarity index between West and North region were relatively higher compared to other regional comparisons.

  2. The influence of Pacific Equatorial Water on fish diversity in the southern California Current System

    Science.gov (United States)

    McClatchie, Sam; Thompson, Andrew R.; Alin, Simone R.; Siedlecki, Samantha; Watson, William; Bograd, Steven J.

    2016-08-01

    The California Undercurrent transports Pacific Equatorial Water (PEW) into the Southern California Bight from the eastern tropical Pacific Ocean. PEW is characterized by higher temperatures and salinities, with lower pH, representing a source of potentially corrosive (aragonite,Ωfish diversity. We use hydrographic data to characterize the interannual and seasonal variability of estimated pH and aragonite saturation with depth. Although there is substantial variability in PEW presence as measured by spice on the 26.25-26.75 isopycnal layer, as well as in pH and aragonite saturation, we found fish diversity to be stable over the decades 1985-1996 and 1999-2011. We detected significant difference in species structure during the 1998 La Niña period, due to reduced species evenness. Species richness due to rare species was higher during the 1997/1998 El Niño compared to the La Niña but the effect on species structure was undetectable. Lack of difference in the species abundance structure in the decade before and after the 1997/1999 ENSO event showed that the assemblage reverted to its former structure following the ENSO perturbation, indicating resilience. While the interdecadal species structure remained stable, the long tail of the distributions shows that species richness increased between the decades consistent with intrusion of warm water with more diverse assemblages into the southern California region.

  3. Connecting ground water influxes with fish species diversity in an urbanized watershed

    Science.gov (United States)

    Steffy, L.Y.; McGinty, A.L.; Welty, C.; Kilham, S.S.

    2004-01-01

    Valley Creek watershed is a small stream system that feeds the Schuylkill River near Philadelphia, Pennsylvania. The watershed is highly urbanized, including over 17 percent impervious surface cover (ISC) by area. Imperviousness in a watershed has been linked to fish community structure and integrity. Generally, above 10 to 12 percent ISC there is marked decline in fish assemblages with fish being absent above 25 percent ISC. This study quantifies the importance of ground water in maintaining fish species diversity in subbasins with over 30 percent ISC. Valley Creek contains an atypical fish assemblage in that the majority of the fish are warm-water species, and the stream supports naturally reproducing brown trout, which were introduced and stocked from the early 1900s to 1985. Fish communities were quantified at 13 stations throughout the watershed, and Simpson's species diversity index was calculated. One hundred and nine springs were located, and their flow rates measured. A cross covariance analysis between Simpson's species diversity index and spring flow rates upstream of fish stations was performed to quantify the spatial correlation between these two variables. The correlation was found to be highest at lag distances up to about 400 m and drop off significantly beyond lag distances of about 800 m.

  4. Insect diversity and water quality parameters of two ponds of Chatla wetland, Barak valley, Assam

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    Susmita Gupta

    2012-12-01

    Full Text Available An investigation was carried out on two ponds of Chatla floodplain, Barak valley, Assam with special reference to aquatic insects. Pond 1 is purely a fish pond where as pond 2 is a community pond too. Present study revealed the status of water quality and in turn diversity, density, dominance and abundance of aquatic insects in both the ponds. Almost all the physico chemical parameters of both the ponds were found within permissible range for aquatic life .However in pond 2 level of phosphate was found little higher than pond 1 due to release of soaps and detergents by human influence. In both the ponds order Hemiptera showed maximum relative abundance ( 98% in pond 1 and 94% in pond 2. The study revealed lower diversity of aquatic insects in pond 2 than that in pond 1.

  5. Diversity of lactic acid bacteria isolated from Brazilian water buffalo mozzarella cheese.

    Science.gov (United States)

    Silva, Luana Faria; Casella, Tiago; Gomes, Elisangela Soares; Nogueira, Mara Correa Lelles; De Dea Lindner, Juliano; Penna, Ana Lúcia Barretto

    2015-02-01

    The water buffalo mozzarella cheese is a typical Italian cheese which has been introduced in the thriving Brazilian market in the last 10 y, with good acceptance by its consumers. Lactic acid bacteria (LAB) play an important role in the technological and sensory quality of mozzarella cheese. In this study, the aim was to evaluate the diversity of the autochthones viable LAB isolated from water buffalo mozzarella cheese under storage. Samples were collected in 3 independent trials in a dairy industry located in the southeast region of Brazil, on the 28th day of storage, at 4 ºC. The LAB were characterized by Gram staining, catalase test, capacity to assimilate citrate, and production of CO2 from glucose. The diversity of LAB was evaluated by RAPD-PCR (randomly amplified polymorphic DNA-polymerase chain reaction), 16S rRNA gene sequencing, and by Vitek 2 system. Twenty LAB strains were isolated and clustered into 12 different clusters, and identified as Streptococcus thermophilus, Enterococcus faecium, Enterococcus durans, Leuconostoc mesenteroides subsp. mesenteroides, Lactobacillus fermentum, Lactobacillus casei, Lactobacillus delbrueckii subsp. bulgaricus, and Lactobacillus helveticus. Enterococcus species were dominant and citrate-positive. Only the strains of L. mesenteroides subsp. mesenteroides and L. fermentum produced CO2 from glucose and were citrate-positive, while L. casei was only citrate positive. This is the first report which elucidates the LAB diversity involved in Brazilian water buffalo mozzarella cheese. Furthermore, the results show that despite the absence of natural whey cultures as starters in production, the LAB species identified are the ones typically found in mozzarella cheese.

  6. Phylogenetic diversity, antibiotic resistance and virulence traits of Aeromonas spp. from untreated waters for human consumption.

    Science.gov (United States)

    Carvalho, Maria João; Martínez-Murcia, Antonio; Esteves, Ana Cristina; Correia, António; Saavedra, Maria José

    2012-10-15

    It is well known that water constitutes an important contamination route for microorganisms. This is especially true for Aeromonas which are widespread in untreated and treated waters. In this study, Portuguese untreated waters not regularly monitored were screened for the presence and diversity of aeromonads. A total of 206 isolates were discriminated by RAPD-PCR and 80 distinct strains were identified by gyrB based phylogenetic analysis. The most frequently detected species were Aeromonas hydrophila, Aeromonas bestiarum and Aeromonas media. The antibiotic susceptibility profile of these strains was determined and showed a typical profile of the genus. Nonetheless, the percentage of resistant strains to tetracycline, chloramphenicol and/or trimethoprim/sulfamethoxazole was lower than that reported for clinical isolates and isolates recovered from aquacultures and other environments historically subjected to antibiotic contamination. This suggests that the existence of such pressures in those environments selects for resistant Aeromonas. A similar trend for integron presence was found. Genes coding for CphA and TEM, and tet(A), (E), (C) or (D) genes were found in 28%, 1%, and 10% of the strains, respectively. 10% of the strains contained an integron. Variable regions of seven class 1 integrons and one class 2 integron were characterised. Furthermore, strains displayed virulence related phenotypes such as extracellular lipolytic and proteolytic activities as well as aerolysin related genes (43% of strains). The ascV and aexT genes were found in 16% and 3% of strains respectively and, in some cases, concomitantly in the same specimen. This study shows that diverse Aeromonas spp. presenting distinct antibiotic resistance features and putative virulence traits are frequently present in waters for human and animal consumption in Portugal. Genes associated to antibiotic resistance and microbial virulence previously identified in organisms with human health significance

  7. Vegetation Water Content Mapping in a Diverse Agricultural Landscape: National Airborne Field Experiment 2006

    Science.gov (United States)

    Cosh, Michael H.; Jing Tao; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2011-01-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE 06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE 06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/sq m. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy. Keywords: Vegetation, field experimentation, thematic mapper, NDWI, agriculture.

  8. Vegetation water content mapping in a diverse agricultural landscape: National Airborne Field Experiment 2006

    Science.gov (United States)

    Cosh, Michael H.; Tao, Jing; Jackson, Thomas J.; McKee, Lynn; O'Neill, Peggy

    2010-05-01

    Mapping land cover and vegetation characteristics on a regional scale is critical to soil moisture retrieval using microwave remote sensing. In aircraft-based experiments such as the National Airborne Field Experiment 2006 (NAFE'06), it is challenging to provide accurate high resolution vegetation information, especially on a daily basis. A technique proposed in previous studies was adapted here to the heterogenous conditions encountered in NAFE'06, which included a hydrologically complex landscape consisting of both irrigated and dryland agriculture. Using field vegetation sampling and ground-based reflectance measurements, the knowledge base for relating the Normalized Difference Water Index (NDWI) and the vegetation water content was extended to a greater diversity of agricultural crops, which included dryland and irrigated wheat, alfalfa, and canola. Critical to the generation of vegetation water content maps, the land cover for this region was determined from satellite visible/infrared imagery and ground surveys with an accuracy of 95.5% and a kappa coefficient of 0.95. The vegetation water content was estimated with a root mean square error of 0.33 kg/m2. The results of this investigation contribute to a more robust database of global vegetation water content observations and demonstrate that the approach can be applied with high accuracy.

  9. Presence of Trifolium repens promotes complementarity of water use and N facilitation in diverse grass mixtures

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    Pauline eHernandez

    2016-04-01

    Full Text Available Legume species promote productivity and increase the digestibility of herbage in grasslands. Considerable experimental data also indicate that communities with legumes produce more above-ground biomass than is expected from monocultures. While it has been attributed to N facilitation, evidence to identify the mechanisms involved is still lacking and the role of complementarity in soil water acquisition by vertical root differentiation remains unclear. We used a 20-month mesocosm experiment to investigate the effects of species richness (single species, two- and five-species mixtures and functional diversity (presence of the legume Trifolium repens on a set of traits related to light, N and water use and measured at community level. We found a positive effect of Trifolium presence and abundance on biomass production and complementarity effects in the two-species mixtures from the second year. In addition the community traits related to water and N acquisition and use (leaf area, N, water-use efficiency and deep root growth were higher in the presence of Trifolium. With a multiple regression approach, we showed that the traits related to water acquisition and use were with N the main determinants of biomass production and complementarity effects in diverse mixtures. At shallow soil layers, lower root mass of Trifolium and higher soil moisture should increase soil water availability for the associated grass species. Conversely at deep soil layer, higher root growth and lower soil moisture mirror soil resource use increase of mixtures. Altogether, these results highlight N facilitation but almost soil vertical differentiation and thus complementarity for water acquisition and use in mixtures with Trifolium. Contrary to grass-Trifolium mixtures, no significant over-yielding was measured for grass mixtures even those having complementary traits (short and shallow vs tall and deep. Thus, vertical complementarity for soil resources uptake in mixtures

  10. Spatial variations in the molecular diversity of dissolved organic matter in water moving through a boreal forest in eastern Finland

    Science.gov (United States)

    Ide, Jun’ichiro; Ohashi, Mizue; Takahashi, Katsutoshi; Sugiyama, Yuko; Piirainen, Sirpa; Kortelainen, Pirkko; Fujitake, Nobuhide; Yamase, Keitaro; Ohte, Nobuhito; Moritani, Mina; Hara, Miyako; Finér, Leena

    2017-01-01

    Dissolved organic matter (DOM) strongly affects water quality within boreal forest ecosystems. However, how the quality of DOM itself changes spatially is not well understood. In this study, to examine how the diversity of DOM molecules varies in water moving through a boreal forest, the number of DOM molecules in different water samples, i.e., rainwater, throughfall, soil water, groundwater, and stream water was determined using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) in Norway spruce and Scots pine stands in eastern Finland during May and June 2010. The number of molecular compounds identified by FT-ICR MS (molecular diversity) ranged from 865 to 2,194, revealing large DOM molecular diversity in the water samples. Additionally, some of the molecular compounds were shared between different water samples. The DOM molecular diversity linearly correlated with the number of low-biodegradable molecules, such as, lignin-like molecules (lignins), but not with dissolved organic carbon concentration. The number of lignins shared between different sampling locations was larger than that of any other biomolecular class. Our results suggest that low-biodegradable molecules, especially lignins, regulate spatial variations in DOM molecular diversity in boreal forests. PMID:28186141

  11. Diversity and functions of bacterial community in drinking water biofilms revealed by high-throughput sequencing

    Science.gov (United States)

    Chao, Yuanqing; Mao, Yanping; Wang, Zhiping; Zhang, Tong

    2015-01-01

    The development of biofilms in drinking water (DW) systems may cause various problems to water quality. To investigate the community structure of biofilms on different pipe materials and the global/specific metabolic functions of DW biofilms, PCR-based 454 pyrosequencing data for 16S rRNA genes and Illumina metagenomic data were generated and analysed. Considerable differences in bacterial diversity and taxonomic structure were identified between biofilms formed on stainless steel and biofilms formed on plastics, indicating that the metallic materials facilitate the formation of higher diversity biofilms. Moreover, variations in several dominant genera were observed during biofilm formation. Based on PCA analysis, the global functions in the DW biofilms were similar to other DW metagenomes. Beyond the global functions, the occurrences and abundances of specific protective genes involved in the glutathione metabolism, the SoxRS system, the OxyR system, RpoS regulated genes, and the production/degradation of extracellular polymeric substances were also evaluated. A near-complete and low-contamination draft genome was constructed from the metagenome of the DW biofilm, based on the coverage and tetranucleotide frequencies, and identified as a Bradyrhizobiaceae-like bacterium according to a phylogenetic analysis. Our findings provide new insight into DW biofilms, especially in terms of their metabolic functions. PMID:26067561

  12. Bacterial diversity and composition of an alkaline uranium mine tailings-water interface.

    Science.gov (United States)

    Khan, Nurul H; Bondici, Viorica F; Medihala, Prabhakara G; Lawrence, John R; Wolfaardt, Gideon M; Warner, Jeff; Korber, Darren R

    2013-10-01

    The microbial diversity and biogeochemical potential associated with a northern Saskatchewan uranium mine water-tailings interface was examined using culture-dependent and -independent techniques. Morphologically-distinct colonies from uranium mine water-tailings and a reference lake (MC) obtained using selective and non-selective media were selected for 16S rRNA gene sequencing and identification, revealing that culturable organisms from the uranium tailings interface were dominated by Firmicutes and Betaproteobacteria; whereas, MC organisms mainly consisted of Bacteroidetes and Gammaproteobacteria. Ion Torrent (IT) 16S rRNA metagenomic analysis carried out on extracted DNA from tailings and MC interfaces demonstrated the dominance of Firmicutes in both of the systems. Overall, the tailings-water interface environment harbored a distinct bacterial community relative to the MC, reflective of the ambient conditions (i.e., total dissolved solids, pH, salinity, conductivity, heavy metals) dominating the uranium tailings system. Significant correlations among the physicochemical data and the major bacterial groups present in the tailings and MC were also observed. Presence of sulfate reducing bacteria demonstrated by culture-dependent analyses and the dominance of Desulfosporosinus spp. indicated by Ion Torrent analyses within the tailings-water interface suggests the existence of anaerobic microenvironments along with the potential for reductive metabolic processes.

  13. Prevalence and diversity of Chlamydiales and other amoeba-resisting bacteria in domestic drinking water systems

    Directory of Open Access Journals (Sweden)

    J. Lienard

    2017-01-01

    Full Text Available A growing number of human infections incriminate environmental bacteria that have evolved virulent mechanisms to resist amoebae and use them as a replicative niche. These bacteria are designated amoeba-resisting bacteria (ARB. Despite the isolation of these ARB in various human clinical samples, the possible source of infection remains undetermined in most cases. However, it is known that the ARB Legionella pneumophila, for instance, causes a respiratory infection in susceptible hosts after inhalation of contaminated water aerosols from various sources. The Chlamydiales order contains many ARB, such as Parachlamydia acanthamoebae or Simkania negevensis, previously implicated in human respiratory infections with no identified contamination sources. We thus investigated whether domestic water systems are a potential source of transmission of these Chlamydiales to humans by using amoebal culture and molecular methods. Other important ARB such as mycobacteria and Legionella were also investigated, as were their possible amoebal hosts. This work reports for the first time a very high prevalence and diversity of Chlamydiales in drinking water, being detected in 35 (72.9% of 48 investigated domestic water systems, with members of the Parachlamydiaceae family being dominantly detected. Furthermore, various Legionella and mycobacteria species were also recovered, some species of which are known to be causal agents of human infections.

  14. Extremely alkaline (pH > 12) ground water hosts diverse microbial community.

    Science.gov (United States)

    Roadcap, George S; Sanford, Robert A; Jin, Qusheng; Pardinas, José R; Bethke, Craig M

    2006-01-01

    Chemically unusual ground water can provide an environment for novel communities of bacteria to develop. Here, we describe a diverse microbial community that inhabits extremely alkaline (pH > 12) ground water from the Lake Calumet area of Chicago, Illinois, where historic dumping of steel slag has filled in a wetland. Using microbial 16S ribosomal ribonucleic acid gene sequencing and microcosm experiments, we confirmed the presence and growth of a variety of alkaliphilic beta-Proteobacteria, Bacillus, and Clostridium species at pH up to 13.2. Many of the bacterial sequences most closely matched those of other alkaliphiles found in more moderately alkaline water around the world. Oxidation of dihydrogen produced by reaction of water with steel slag is likely a primary energy source to the community. The widespread occurrence of iron-oxidizing bacteria suggests that reduced iron serves as an additional energy source. These results extend upward the known range of pH tolerance for a microbial community by as much as 2 pH units. The community may provide a source of novel microbes and enzymes that can be exploited under alkaline conditions.

  15. The Impact of Water Diversion on Groundwater Resources in an Inland River Basin

    Science.gov (United States)

    Huang, L.; Zheng, C.

    2012-12-01

    The Heihe River Basin (HRB) is one of the most intensely exploited and ecologically stressed inland river basins in the world. The HRB is characterized by three distinct ecohydrological systems: the mountainous upper reach where most of the water resources for the HRB originate from the rainfall, snow and permafrost; the middle reach with an arid climate and irrigated agriculture; and the lower reach dominated by wide stretches of Gobi desert. The study site, Zhangye Basin, is situated in the middle reach. It contains 92% population of the HRB and consumes about 80% of water resources as a regional agricultural and industrial center. To improve the deteriorating health of the ecosystems in the lower HRB, the Chinese government initiated the Heihe Water Diversion Project (HWDP) in 2000, which stipulated that at least 0.95 billion cubic meters of surface water must be delivered from the middle reach to the lower reach annually. A three-dimensional groundwater flow model has been developed for the Zhangye Basin to understand groundwater-surface water interactions in the Zhangye Basin and assess how the HWDP project has impacted the groundwater availability and water budgets in the region. The flow model has been reasonably calibrated using multiple sources of field data. The output of the groundwater model provided estimates of head differences before and after the HWDP project between 1999 and 2010. The results show that the groundwater level has declined widely, except in the Zhangye urban area where the groundwater level has increased by 0.5 to 7m and a few other localized spots. The calculated water budgets indicate that the spring discharge to the Heihe River has been continuously decreasing, and the total river leakage to the aquifer has been increasing. These results are in reasonable agreement with those from previous studies based on independent water balance calculation. The groundwater model is being integrated with surface water and land use data to

  16. Evaluation of anthropogenic effects on water quality and bacterial diversity in Rawal Lake, Islamabad.

    Science.gov (United States)

    Saeed, Asma; Hashmi, Imran

    2014-05-01

    Water quality and bacterial diversity in the surface water of Rawal Lake was investigated for a period of 8 months to evaluate the pollution load from anthropogenic effects of surrounding areas. Rawal Lake in Islamabad, Pakistan is an artificial reservoir that provides the water needs for the residents of Rawalpindi and Islamabad. Grabbed water samples were collected according to standard protocols from ten different locations of the lake and tributaries keeping in view the recharge points from adjacent areas. Temperature, pH, electrical conductivity, dissolved oxygen, total dissolved solids, hardness, alkalinity, and turbidity of water samples were determined to study the water quality characteristics. The physicochemical parameters showed higher values at the tributaries as compared to the sampling locations within the lake such as values of hardness and alkalinity were 298 and 244 mg/L, respectively, at the tributary of the Nurpur stream. Bacterial strains were isolated by streaking on differential and selective growth media by observing colony morphology and other biochemical tests such as Gram reaction, oxidase, and catalase test. Template DNA was prepared from pure cultivated bacteria and 16S rRNA gene analysis was performed using universal primers for bacteria. Sequencing was performed by using BigDye terminator cycle sequencing kit. Sequences of nearest relative microbial species were identified by using basic local alignment search tool and used as reference sequences for phylogenetic analysis. Phylogenetic trees were inferred using the neighbor-joining method. Sequencing and phylogenetic characterization of microbes showed various phylotypes, of which Firmicutes, Teobacteria, and Proteobacteria were predominant.

  17. Water-energy dynamics, habitat heterogeneity, history, and broad-scale patterns of mammal diversity

    Science.gov (United States)

    Ferrer-Castán, Dolores; Morales-Barbero, Jennifer; Vetaas, Ole R.

    2016-11-01

    Numerous hypotheses on diversity patterns are often presented as if they were mutually exclusive. However, because of multicollinearity, correlational analyses are not able to distinguish the causal effects of different factors on these patterns. For this reason, we examine the interrelationships among current climate, habitat heterogeneity and evolutionary history by partitioning the variation in both total and non-volant mammal species richness in the Iberian Peninsula. Thus, it is possible to determine the variation accounted for by each one of these three components that is not shared by the others, and the respective overlaps. More specifically, we hypothesize that (H1) in warm temperate zones, a small increase in the available energy has strong negative effects on mammal richness if water availability is limiting; (H2) there are functional relationships between woody plant species richness (WOOD) and the richness of mammal species; (H3) there is a signal of evolutionary history in contemporary patterns of species richness, and (H4) mammal richness and the historical variable mean root distance (MRD) respond to the same driving forces. Additionally, we also test for spatial autocorrelation. We found a sharp nonlinear decrease in mammal richness with increasing energy and a monotonic increase with increasing water availability. Moreover, an interaction term between these two climate factors appeared to be statistically significant, so H1 could not be rejected. WOOD remained significant after partialling out both current climate and MRD at the family level (MRDf), supporting H2. The relationship between mammal diversity and MRD averaged by species richness was found to be spurious, but there appeared a significant historical signal using MRDf (this supports H3). The overlaps among these factors are consistent with H4 and suggest that water-energy dynamics have probably been active drivers throughout evolutionary history with habitat heterogeneity, and biotic

  18. Effects analysis of river water quality improvement by water diversion%引调水改善河流水质的效果分析

    Institute of Scientific and Technical Information of China (English)

    卢卫; 应聪惠

    2014-01-01

    For plain river network area, the factors influencing effects of river water quality improvement by water diversion are various due to the complicated flow condition. We propose water diversion improvement efficiency as the judging basis to deter-mine optimal water diversion solution, and further carry out effect analysis on river water quality improvement by water diversion for Shangtanghe River watershed in Zhejiang Province using the hydrodynamics and water quality module of MIKE11 software, in which the diverted water quantity, diversion duration as well as diverted modes are comprehensively considered. The results show that the staged water diversion solution is better than the continuous water diversion solution, because it can obtain the same im-proving effect but consume less time and water volume, therefore the staged water diversion solution can gain the same social ben-efits and better economical benefits.%平原河网地区水流流向复杂,影响引调水改善河网水质效果的因素众多。以浙江省杭嘉湖平原地区的上塘河流域为例,运用MIKE11水动力与水质模型并综合考虑上塘河引调水水量、历时及引水模式,研究了河网引调水改善水质的效果,并提出以引调水效率作为确定最佳引调水方案的依据。研究表明,阶段性引调水的效率优于连续性引调水,能在减少实际引调水历时与水量的同时,达到与连续性引调水相近的改善水质效果,从而在取得相近社会效益的同时,获得更佳的经济效益。

  19. [Diversity of plant in Jiaxing Shijiuyang ecological wetland for drinking water during operation].

    Science.gov (United States)

    Shen, Ya-Qiang; Wei, Hong-Bin; Cheng, Wang-Da; Zhang, Hong-Mei; Wang, Wei-Dong; Yin, Cheng-Qing

    2011-10-01

    The Shijiuyang ecological wetland for drinking water of Jiaxing City, Zhejiang Province is one of the biggest constructed wetlands for water resource protection in China. To ensure a deep understanding of the present status of the wetland vegetation of Shijiuyang ecological wetland which has been run for 2.5 years and provide support for the vegetation management of ecological wetland, systematic investigation was carried out by using plot method and quadrat method in October to November, 2010. The species composition, dynamics of plant diversity and the biomass production during operation were analyzed. Altogether 70 species belonging to 28 families and 62 genera were recorded. Among them, there were 26 wetland plants, 20 mesophytes, 14 emergent, 4 submerged, 6 floating ones. Compared with the preliminary stage, the species numbers of wetland plants increased significantly from 15 species to 70 species. The spatial pattern of riparian species diversity was examined by adopting the Simpson index and Shannon-Wiener index as species diversity indices. The results showed that the riparian species diversity was higher in the west of the Beijiaohe river (Simpson index = 0.468 3, Shannon-Wiener index = 0.835 2) than that in the south of the Dongsheng Road (Simpson index = 0.357 6, Shannon-Wiener index = 0.660 4). The analyses of quantitative characteristics of wetland vegetation showed that the plants in the root-channel purification zone in the south of the Dongsheng Road grew better than those in the west of the Beijiaohe river. With regard to the riparian vegetation, the riparian plants in the west of the Beijiaohe river were more abundant. The mean biomass production (dry weight) in the root-channel purification zone was 1.73 kg x m(-2) and the total area was 9.12 x 10(4) m2, so the total biomass production was estimated to be 157.8 t. In the same way, the mean riparian vegetation biomass production(dry weight) was 0.83 kg x m(-2) and the total vegetation area was 3

  20. Relationships between host phylogeny, host type and bacterial community diversity in cold-water coral reef sponges.

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    Sandra Schöttner

    Full Text Available Cold-water coral reefs are known to locally enhance the diversity of deep-sea fauna as well as of microbes. Sponges are among the most diverse faunal groups in these ecosystems, and many of them host large abundances of microbes in their tissues. In this study, twelve sponge species from three cold-water coral reefs off Norway were investigated for the relationship between sponge phylogenetic classification (species and family level, as well as sponge type (high versus low microbial abundance, and the diversity of sponge-associated bacterial communities, taking also geographic location and water depth into account. Community analysis by Automated Ribosomal Intergenic Spacer Analysis (ARISA showed that as many as 345 (79% of the 437 different bacterial operational taxonomic units (OTUs detected in the dataset were shared between sponges and sediments, while only 70 (16% appeared purely sponge-associated. Furthermore, changes in bacterial community structure were significantly related to sponge species (63% of explained community variation, sponge family (52% or sponge type (30%, whereas mesoscale geographic distances and water depth showed comparatively small effects (<5% each. In addition, a highly significant, positive relationship between bacterial community dissimilarity and sponge phylogenetic distance was observed within the ancient family of the Geodiidae. Overall, the high diversity of sponges in cold-water coral reefs, combined with the observed sponge-related variation in bacterial community structure, support the idea that sponges represent heterogeneous, yet structured microbial habitats that contribute significantly to enhancing bacterial diversity in deep-sea ecosystems.

  1. Supporting diverse data providers in the open water data initiative: Communicating water data quality and fitness of use

    Science.gov (United States)

    Larsen, Sara; Hamilton, Stuart; Lucido, Jessica M.; Garner, Bradley D.; Young, Dwane

    2016-01-01

    Shared, trusted, timely data are essential elements for the cooperation needed to optimize economic, ecologic, and public safety concerns related to water. The Open Water Data Initiative (OWDI) will provide a fully scalable platform that can support a wide variety of data from many diverse providers. Many of these will be larger, well-established, and trusted agencies with a history of providing well-documented, standardized, and archive-ready products. However, some potential partners may be smaller, distributed, and relatively unknown or untested as data providers. The data these partners will provide are valuable and can be used to fill in many data gaps, but can also be variable in quality or supplied in nonstandardized formats. They may also reflect the smaller partners' variable budgets and missions, be intermittent, or of unknown provenance. A challenge for the OWDI will be to convey the quality and the contextual “fitness” of data from providers other than the most trusted brands. This article reviews past and current methods for documenting data quality. Three case studies are provided that describe processes and pathways for effective data-sharing and publication initiatives. They also illustrate how partners may work together to find a metadata reporting threshold that encourages participation while maintaining high data integrity. And lastly, potential governance is proposed that may assist smaller partners with short- and long-term participation in the OWDI.

  2. Dynamic diversity of synthetic supramolecular polymers in water as revealed by hydrogen/deuterium exchange

    Science.gov (United States)

    Lou, Xianwen; Lafleur, René P. M.; Leenders, Christianus M. A.; Schoenmakers, Sandra M. C.; Matsumoto, Nicholas M.; Baker, Matthew B.; van Dongen, Joost L. J.; Palmans, Anja R. A.; Meijer, E. W.

    2017-05-01

    Numerous self-assembling molecules have been synthesized aiming at mimicking both the structural and dynamic properties found in living systems. Here we show the application of hydrogen/deuterium exchange (HDX) mass spectrometry (MS) to unravel the nanoscale organization and the structural dynamics of synthetic supramolecular polymers in water. We select benzene-1,3,5-tricarboxamide (BTA) derivatives that self-assemble in H2O to illustrate the strength of this technique for supramolecular polymers. The BTA structure has six exchangeable hydrogen atoms and we follow their exchange as a function of time after diluting the H2O solution with a 100-fold excess of D2O. The kinetic H/D exchange profiles reveal that these supramolecular polymers in water are dynamically diverse; a notion that has previously not been observed using other techniques. In addition, we report that small changes in the molecular structure can be used to control the dynamics of synthetic supramolecular polymers in water.

  3. Global diversity of aloricate Oligotrichea (Protista, Ciliophora, Spirotricha) in marine and brackish sea water.

    Science.gov (United States)

    Agatha, Sabine

    2011-01-01

    Oligotrichids and choreotrichids are ciliate taxa contributing to the multi-step microbial food web and episodically dominating the marine microzooplankton. The global diversity and distribution of aloricate Oligotrichea are unknown. Here, the geographic ranges of the 141 accepted species and their synonyms in marine and brackish sea water are analyzed, using hundreds of taxonomical and ecological studies; the quality of the records is simultaneously evaluated. The aloricate Oligotrichea match the moderate endemicity model, i.e., the majority (94) of morphospecies has a wide, occasionally cosmopolitan distribution, while 47 morphospecies show biogeographic patterns: they are restricted to single geographic regions and probably include 12 endemic morphospecies. These endemics are found in the Antarctic, North Pacific, and Black Sea, whereas the "flagship" species Strombidinopsis cercionis is confined to the Caribbean Sea. Concerning genera, again several geographic patterns are recognizable. The species richness is distinctly lower in the southern hemisphere than in the northern, ranging from nine morphospecies in the South Pacific to 95 in the North Atlantic; however, this pattern is probably caused by undersampling. Since the loss of species might affect higher trophical levels substantially, the aloricate Oligotrichea should not any longer be ignored in conservation issues. The ecophysiological diversity is considerably larger than the morphological, and even tops the richness of SSrRNA and ITS haplotypes, indicating that probably more than 83-89% of the diversity in aloricate Oligotrichea are unknown. The huge challenge to discover all these species can only be managed by combining the expertises of morphological taxonomists, molecular biologists, ecologists, and physiologists.

  4. Global diversity of aloricate Oligotrichea (Protista, Ciliophora, Spirotricha in marine and brackish sea water.

    Directory of Open Access Journals (Sweden)

    Sabine Agatha

    Full Text Available Oligotrichids and choreotrichids are ciliate taxa contributing to the multi-step microbial food web and episodically dominating the marine microzooplankton. The global diversity and distribution of aloricate Oligotrichea are unknown. Here, the geographic ranges of the 141 accepted species and their synonyms in marine and brackish sea water are analyzed, using hundreds of taxonomical and ecological studies; the quality of the records is simultaneously evaluated. The aloricate Oligotrichea match the moderate endemicity model, i.e., the majority (94 of morphospecies has a wide, occasionally cosmopolitan distribution, while 47 morphospecies show biogeographic patterns: they are restricted to single geographic regions and probably include 12 endemic morphospecies. These endemics are found in the Antarctic, North Pacific, and Black Sea, whereas the "flagship" species Strombidinopsis cercionis is confined to the Caribbean Sea. Concerning genera, again several geographic patterns are recognizable. The species richness is distinctly lower in the southern hemisphere than in the northern, ranging from nine morphospecies in the South Pacific to 95 in the North Atlantic; however, this pattern is probably caused by undersampling. Since the loss of species might affect higher trophical levels substantially, the aloricate Oligotrichea should not any longer be ignored in conservation issues. The ecophysiological diversity is considerably larger than the morphological, and even tops the richness of SSrRNA and ITS haplotypes, indicating that probably more than 83-89% of the diversity in aloricate Oligotrichea are unknown. The huge challenge to discover all these species can only be managed by combining the expertises of morphological taxonomists, molecular biologists, ecologists, and physiologists.

  5. The role of canopy hydrological diversity and complexity on water balance and carbon sequestration during dry conditions: a modeling study

    Science.gov (United States)

    Lin, L.; Stewart, A.; Band, L. E.

    2016-12-01

    The importance and influence of forest to catchment hydrology have been well recognized. In the South Eastern U.S., Chapel Hill, NC, evapotranspiration by forest dominates almost 80% of the annual precipitation in long term average. Stomatal conductivity varies by tree species and its response to dry condition differently between evergreen and deciduous, and within their phonology groups. In this study, we simulated the catchment hydrology and forest ecosystem at a local catchment, Cane Creek, in the Chapel Hill triangle area using a spatially distributed, process-based hydro-ecological model, RHESSys. We incorporated characteristics of individual tree species to represent high hydrological diversity (e.g., maple, oak, pine), which has been modeled as either evergreen or deciduous (low hydrological diversity) in many studies. With tree species specifically modeled, we were able to investigate the role of tree species diversity and complexity on catchment hydrology. Local forest plant diversity, size, and density were provided by the U.S. Forest Services FIA, and tree species physiological parameters were obtained through researches at Duke Forest. High hydrological diversity canopy has higher water use and carbon sequestration than low hydrological diversity canopy. This result supports the optimality theory that emergent vegetation pattern in landscape maximizes ecosystem productivity and water use efficiency. Previous study emphasized this emergent pattern in terms of vegetation density along the hillslope gradient, and we further emphasized the emergent pattern in terms of hydrological diversity in this study.

  6. Diversity and antimicrobial resistance of Salmonella enterica isolates from surface water in Southeastern United States.

    Science.gov (United States)

    Li, Baoguang; Vellidis, George; Liu, Huanli; Jay-Russell, Michele; Zhao, Shaohua; Hu, Zonglin; Wright, Anita; Elkins, Christopher A

    2014-10-01

    A study of prevalence, diversity, and antimicrobial resistance of Salmonella enterica in surface water in the southeastern United States was conducted. A new scheme was developed for recovery of Salmonella from irrigation pond water and compared with the FDA's Bacteriological Analytical Manual (8th ed., 2014) (BAM) method. Fifty-one isolates were recovered from 10 irrigation ponds in produce farms over a 2-year period; nine Salmonella serovars were identified by pulsed-field gel electrophoresis analysis, and the major serovar was Salmonella enterica serovar Newport (S. Newport, n = 29), followed by S. enterica serovar Enteritidis (n = 6), S. enterica serovar Muenchen (n = 4), S. enterica serovar Javiana (n = 3), S. enterica serovar Thompson (n = 2), and other serovars. It is noteworthy that the PulseNet patterns of some of the isolates were identical to those of the strains that were associated with the S. Thompson outbreaks in 2010, 2012, and 2013, S. Enteritidis outbreaks in 2011 and 2013, and an S. Javiana outbreak in 2012. Antimicrobial susceptibility testing confirmed 16 S. Newport isolates of the multidrug resistant-AmpC (MDR-AmpC) phenotype, which exhibited resistance to ampicillin, chloramphenicol, streptomycin, sulfamethoxazole, and tetracycline (ACSSuT), and to the 1st, 2nd, and 3rd generations of cephalosporins (cephalothin, amoxicillin-clavulanic acid, and ceftriaxone). Moreover, the S. Newport MDR-AmpC isolates had a PFGE pattern indistinguishable from the patterns of the isolates from clinical settings. These findings suggest that the irrigation water may be a potential source of contamination of Salmonella in fresh produce. The new Salmonella isolation scheme significantly increased recovery efficiency from 21.2 (36/170) to 29.4% (50/170) (P = 0.0002) and streamlined the turnaround time from 5 to 9 days with the BAM method to 4 days and thus may facilitate microbiological analysis of environmental water. Copyright © 2014, American Society for

  7. Microbial diversity and methanogenic activity of Antrim Shale formation waters from recently fractured wells.

    Directory of Open Access Journals (Sweden)

    Cornelia eWuchter

    2013-12-01

    Full Text Available The Antrim Shale in the Michigan Basin is one of the most productive shale gas formations in the U.S, but optimal resource recovery strategies must rely on a thorough understanding of the complex biogeochemical, microbial, and physical interdependencies in this and similar systems. We used Illumina Miseq 16S rDNA sequencing to analyze the diversity and relative abundance of prokaryotic communities present in Antrim shale formation water of three closely spaced recently fractured gas-producing wells. In addition, the well waters were incubated with a suite of fermentative and methanogenic substrates in an effort to stimulate microbial methane generation. The three wells exhibited substantial differences in their community structure that may arise from their different drilling and fracturing histories. Bacterial sequences greatly outnumbered those of archaea and shared highest similarity to previously described cultures of mesophiles and moderately halophiles within the Firmicutes, Bacteroidetes, and δ- and ε-Proteobacteria. The majority of archaeal sequences shared highest sequence similarity to uncultured euryarchaeotal environmental clones. Some sequences closely related to cultured methylotrophic and hydrogenotrophic methanogens were also present in the initial well water. Incubation with methanol and trimethylamine stimulated methylotrophic methanogens and resulted in the largest increase in methane production in the formation waters, while fermentation triggered by the addition of yeast extract and formate indirectly stimulated hydrogenotrophic methanogens. The addition of sterile powdered shale as a complex natural substrate stimulated the rate of methane production without affecting total methane yields. Depletion of methane indicative of anaerobic methane oxidation was observed over the course of incubation with some substrates. This process could constitute a substantial loss of methane in the shale formation.

  8. [Effects of nitrogen and water addition on soil bacterial diversity and community structure in temperate grasslands in northern China].

    Science.gov (United States)

    Yang, Shan; Li, Xiao-bing; Wang, Ru-zhen; Cai, Jiang-ping; Xu, Zhu-wen; Zhang, Yu-ge; Li, Hui; Jiang, Yong

    2015-03-01

    In this study, we measured the responses of soil bacterial diversity and community structure to nitrogen (N) and water addition in the typical temperate grassland in northern China. Results showed that N addition significantly reduced microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) under regular precipitation treatment. Similar declined trends of MBC and MBN caused by N addition were also found under increased precipitation condition. Nevertheless, water addition alleviated the inhibition by N addition. N addition exerted no significant effects. on bacterial α-diversity indices, including richness, Shannon diversity and evenness index under regular precipitation condition. Precipitation increment tended to increase bacterial α-diversity, and the diversity indices of each N gradient under regular precipitation were much lower than that of the corresponding N addition rate under increased precipitation. Correlation analysis showed that soil moisture, nitrate (NO3(-)-N) and ammonium (NH4+-N) were significantly negatively correlated with bacterial evenness index, and MBC and MBN had a significant positive correlation with bacterial richness and evenness. Non-metric multidimensional scaling (NMDS) ordination illustrated that the bacterial communities were significantly separated by N addition rates, under both water ambient and water addition treatments. Redundancy analysis (RDA) revealed that soil MBC, MBN, pH and NH4+-N were the key environmental factors for shaping bacterial communities.

  9. Effects of Surface-Water Diversions on Habitat Availability for Native Macrofauna, Northeast Maui, Hawaii

    Science.gov (United States)

    Gingerich, Stephen B.; Wolff, Reuben H.

    2005-01-01

    Effects of surface-water diversions on habitat availability for native stream fauna (fish, shrimp, and snails) are described for 21 streams in northeast Maui, Hawaii. Five streams (Waikamoi, Honomanu, Wailuanui, Kopiliula, and Hanawi Streams) were chosen as representative streams for intensive study. On each of the five streams, three representative reaches were selected: (1) immediately upstream of major surface-water diversions, (2) midway to the coast, and (3) near the coast. This study focused on five amphidromous native aquatic species (alamoo, nopili, nakea, opae, and hihiwai) that are abundant in the study area. The Physical Habitat Simulation (PHABSIM) System, which incorporates hydrology, stream morphology and microhabitat preferences to explore relations between streamflow and habitat availability, was used to simulate habitat/discharge relations for various species and life stages, and to provide quantitative habitat comparisons at different streamflows of interest. Hydrologic data, collected over a range of low-flow discharges, were used to calibrate hydraulic models of selected transects across the streams. The models were then used to predict water depth and velocity (expressed as a Froude number) over a range of discharges up to estimates of natural median streamflow. The biological importance of the stream hydraulic attributes was then assessed with the statistically derived suitability criteria for each native species and life stage that were developed as part of this study to produce a relation between discharge and habitat availability. The final output was expressed as a weighted habitat area of streambed for a representative stream reach. PHABSIM model results are presented to show the area of estimated usable bed habitat over a range of streamflows relative to natural conditions. In general, the models show a continuous decrease in habitat for all modeled species as streamflow is decreased from natural conditions. The PHABSIM modeling results

  10. Phytoplankton diversity in the Parangipettai coastal waters, southeast coast of India.

    Science.gov (United States)

    Rajkumar, M; Rajasekar, K Thillai; Sun, Jun; Jenkinson, I R; Prabu, V Ashok; Perumal, P

    2012-11-01

    An investigation was carried out during June 2005 to May 2007 on hydrography, composition and community structure of phytoplankton including chlorophyll a in Parangipettai coastal waters (southeast coast of India). Air and surface water temperatures varied from 25.5 to 31.2 degrees C and from 25 to 29.3 degrees C, respectively. Salinity values varied from 5 to 33.1 per thousand and the pH ranged between 7.2 and 8.3. Dissolved oxygen content varied from 3.1 to 7.9 mg l(-1) while the light extinction coefficient values (LEC) ranged between 1.8 and 11.0 cm. The range of inorganic nutrients viz., nitrate, nitrite, phosphate and silicate were: 6.5 - 27.0 microM; 1.0 - 8.9 microM; 0.1 - 3.0 microM and 15.0 - 140 microM, respectively. The range of chlorophyll a was: 2.0 - 7.5 microg l(-1). Presently, 117 phytoplankton species representing different classes viz: Bacillariophyceae (66); Dinophyceae (22); Cyanophyceae (19); Chlorophyceae (7) and Chrysophyceae (3) were recorded. The phytoplankton cell abundance varied from 0.14 to 132 cells ml(-1), with peak diversity (3.52 bits ind.(-1)) during summer season. The maximum abundance was found during summer season coinciding with the stable hydrographical conditions. Canonical Correspondence Analysis was applied in this study for discriminating environmental factors effecting on phytoplankton community at species level.

  11. Microbiological Diversity of the Anaerobic Sludge During Treatment of Venezuelan Oilfield Produced Waters

    Directory of Open Access Journals (Sweden)

    Cajacuri María Patricia

    2013-06-01

    Full Text Available In the present investigation the microbial abundances in the granular sludge of two upflow anaerobic sludge blanket reactors (UASB were compared: the first one fed with production waters of light oil (31.1-39.0° API, from the zuliana region (Venezuela (APP and the second one with glucose. To this respect, the populations of glucose fermenting bacteria (BFG, acetogenic bacteria (BAC, metanogens (MET, sulfatereducing bacteria (BSR, nitrate-reducing bacteria (BNRand heterotrophic bacteria were monitored, using selective culture media. The microbial density was correlated with physicochemical parameters: pH, total alkalinity, COD, SO4 =, NO3-, as well as with the percentages of CH4, CO2 and N2in the biogas. The results exhibit significant differences between the microbial diversity of both reactors, with a proportion of BFG > BSR > MET > BAC > BNR for the glucose reactor and of MET > BNR > BAC > BSR > BFG for the APP. The abundance of bacteria in the glucose reactor was in the order of 108, whereas in the APP reactor was of 105, which ensues from the organic and mineral composition of effluents. The results presented in this study reach evidences on the population dynamics in sludge of UASB reactors, during the treatment of oilfield produced waters.

  12. Bacterial abundance and diversity in pond water supplied with different feeds

    Science.gov (United States)

    Qin, Ya; Hou, Jie; Deng, Ming; Liu, Quansheng; Wu, Chongwei; Ji, Yingjie; He, Xugang

    2016-10-01

    The abundance and diversity of bacteria in two types of ponds were investigated by quantitative PCR and Illumina MiSeq sequencing. The results revealed that the abundance of bacterial 16S rRNA genes in D ponds (with grass carp fed sudan grass) was significantly lower than that in E ponds (with grass carp fed commercial feed). The microbial communities were dominated by Proteobacteria, Cyanobacteria, Bacteroidetes, and Actinobacteria in both E and D ponds, while the abundance of some genera was significantly different between the two types of ponds. Specifically, some potential pathogens such as Acinetobacter and Aeromonas were found to be significantly decreased, while some probiotics such as Comamonadaceae unclassified and Bacillales unclassified were significantly increased in D ponds. In addition, water quality of D ponds was better than that of E ponds. Temperature, dissolved oxygen and nutrients had significant influence on bacterial communities. The differences in bacterial community compositions between the two types of ponds could be partially explained by the different water conditions.

  13. Diversity and distribution of polyphagan water beetles (Coleoptera in the Lake St Lucia system, South Africa

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    Matthew S. Bird

    2017-02-01

    Full Text Available Water beetles belonging to the suborder Polyphaga vary greatly in larval and adult ecologies, and fulfil important functional roles in shallow-water ecosystems by processing plant material, scavenging and through predation. This study investigates the species richness and composition of aquatic polyphagan assemblages in and around the St Lucia estuarine lake (South Africa, within the iSimangaliso Wetland Park, a UNESCO World Heritage Site. A total of 32 sites were sampled over three consecutive collection trips between 2013 and 2015. The sites encompassed a broad range of aquatic habitats, being representative of the variety of freshwater and estuarine environments present on the St Lucia coastal plain. Thirty-seven polyphagan taxa were recorded during the dedicated surveys of this study, in addition to seven species-level records from historical collections. Most beetles recorded are relatively widespread Afrotropical species and only three are endemic to South Africa. Samples were dominated by members of the Hydrophilidae (27 taxa, one of which was new to science (Hydrobiomorpha perissinottoi Bilton, 2016. Despite the fauna being dominated by relatively widespread taxa, five represent new records for South Africa, highlighting the poor state of knowledge on water beetle distribution patterns in the region. Wetlands within the dense woodland characterising the False Bay region of St Lucia supported a distinct assemblage of polyphagan beetles, whilst sites occurring on the Eastern and Western Shores of Lake St Lucia were very similar in their beetle composition. In line with the Afrotropical region as a whole, the aquatic Polyphaga of St Lucia appear to be less diverse than the Hydradephaga, for which 68 species were recorded during the same period. However, the results of the present study, in conjunction with those for Hydradephaga, show that the iSimangaliso Wetland Park contains a high beetle diversity. The ongoing and future ecological

  14. Diversity and distribution of polyphagan water beetles (Coleoptera) in the Lake St Lucia system, South Africa

    Science.gov (United States)

    Bird, Matthew S.; Bilton, David T.; Perissinotto, Renzo

    2017-01-01

    Abstract Water beetles belonging to the suborder Polyphaga vary greatly in larval and adult ecologies, and fulfil important functional roles in shallow-water ecosystems by processing plant material, scavenging and through predation. This study investigates the species richness and composition of aquatic polyphagan assemblages in and around the St Lucia estuarine lake (South Africa), within the iSimangaliso Wetland Park, a UNESCO World Heritage Site. A total of 32 sites were sampled over three consecutive collection trips between 2013 and 2015. The sites encompassed a broad range of aquatic habitats, being representative of the variety of freshwater and estuarine environments present on the St Lucia coastal plain. Thirty-seven polyphagan taxa were recorded during the dedicated surveys of this study, in addition to seven species-level records from historical collections. Most beetles recorded are relatively widespread Afrotropical species and only three are endemic to South Africa. Samples were dominated by members of the Hydrophilidae (27 taxa), one of which was new to science (Hydrobiomorpha perissinottoi Bilton, 2016). Despite the fauna being dominated by relatively widespread taxa, five represent new records for South Africa, highlighting the poor state of knowledge on water beetle distribution patterns in the region. Wetlands within the dense woodland characterising the False Bay region of St Lucia supported a distinct assemblage of polyphagan beetles, whilst sites occurring on the Eastern and Western Shores of Lake St Lucia were very similar in their beetle composition. In line with the Afrotropical region as a whole, the aquatic Polyphaga of St Lucia appear to be less diverse than the Hydradephaga, for which 68 species were recorded during the same period. However, the results of the present study, in conjunction with those for Hydradephaga, show that the iSimangaliso Wetland Park contains a high beetle diversity. The ongoing and future ecological protection

  15. Abundance and diversity of Odonata in temporary water bodies of Coimbatore and Salem districts in Tamil Nadu

    Directory of Open Access Journals (Sweden)

    R. Arulprakash

    2010-07-01

    Full Text Available Odonata diversity was assessed in 13 temporary water bodies of Coimbatore and Salem districts in Tamil Nadu. Assessment revealed the presence of 21 species of Odonata (14 species of Anisoptera and seven species of Zygoptera belonging to 17 genera under four families. Libellulidae (Anisoptera was represented by the maximum number of species and individuals. Pantala flavescens (Libellulidae was the most abundant among 21 species. Among the temporary water bodies, the maximum number of individuals as well as species was recorded from Utkulam tank (Coimbatore district. Odonata diversity was higher in Kamalapuram tanks 1 and 2 (Salem district and lower in Ukkadam tank (Coimbatore District. Diplacodes trivialis (Rambur, Orthetrum sabina (Drury and Pantala flavescens (Fabricius were identified as temporary water body specialists because of their presence in all the 13 temporary water bodies sampled.

  16. Effects of Seasonal Thermal Stratification on the Functional Diversity and Composition of the Microbial Community in a Drinking Water Reservoir

    Directory of Open Access Journals (Sweden)

    Xiao Yang

    2015-10-01

    Full Text Available The microbial communities within reservoir ecosystems are shaped by water quality and hydrological characteristics. However, there are few studies focused on the effects of thermal stratification on the bacterial community diversity in drinking water reservoirs. In this study, we collected water samples from the Jinpen Reservoir around the re-stratification period. To explore the functional diversity and bacterial community composition, we used the Biolog method and 16S rRNA-based 454 pyrosequencing combined with flow cytometry. The results indicated that stratification of the reservoir had great effects on temperature and oxygen profiles, and both the functional diversity and the composition of the bacterial community strongly reflected the significant vertical stratification in the reservoir. The results of the Biolog method showed a significantly higher utilization of carbon sources in the hypolimnion than in the epilimnion. The result of pyrosequencing also showed a significantly higher species diversity and richness in the hypolimnion than in the epilimnion with different dominant phylum. Redundancy analysis also indicated that the majority of environmental variables, especially pH and dissolved oxygen, played key roles in shaping bacterial community composition. Our study provides a better understanding of the functional diversity of bacterial communities, and the response of microorganisms to seasonal thermal stratification.

  17. Assessment of fungal diversity in a water-damaged office building.

    Science.gov (United States)

    Green, Brett J; Lemons, Angela R; Park, Yeonmi; Cox-Ganser, Jean M; Park, Ju-Hyeong

    2017-04-01

    Recent studies have described fungal communities in indoor environments using gene sequencing-based approaches. In this study, dust-borne fungal communities were elucidated from a water-damaged office building located in the northeastern region of the United States using internal transcribed spacer (ITS) rRNA gene sequencing. Genomic DNA was extracted from 5 mg of floor dust derived from 22 samples collected from either the lower floors (n = 8) or a top floor (n = 14) of the office building. ITS gene sequencing resolved a total of 933 ITS sequences and was clustered into 216 fungal operational taxonomic units (OTUs). Analysis of fungal OTUs at the 97% similarity threshold showed a difference between the lower and top floors that was marginally significant (p = 0.049). Species richness and diversity indices were reduced in the lower floor samples compared to the top floor samples and there was a high degree of compositional dissimilarity within and between the two different areas within the building. Fungal OTUs were placed in the phyla Ascomycota (55%), Basidiomycota (41%), Zygomycota (3%), Glomeromycota (0.4%), Chytridiomycota (0.3%), and unassigned fungi (0.5%). The Ascomycota classes with the highest relative abundances included the Dothideomycetes (30%) and Eurotiomycetes (16%). The Basidiomycota consisted of the classes Ustilaginomycetes (14%), Tremellomycetes (11%), and Agaricomycetes (8%). Sequence reads derived from the plant pathogen Ustilago syntherismae were the most abundant in the analysis as were obligate Basidiomycota yeast species that accounted for 12% and 11% of fungal ITS sequences, respectively. ITS gene sequencing provides additional insight into the diversity of fungal OTUs. These data further highlight the contribution of fungi placed in the phylum Basidiomycota, obligate yeasts, as well as xerophilic species that are typically not resolved using traditional culture methods.

  18. Phenotypic and Genetic Diversity of Aeromonas Species Isolated from Fresh Water Lakes in Malaysia.

    Science.gov (United States)

    Khor, Wei Ching; Puah, Suat Moi; Tan, Jin Ai Mary Anne; Puthucheary, S D; Chua, Kek Heng

    2015-01-01

    Gram-negative bacilli of the genus Aeromonas are primarily inhabitants of the aquatic environment. Humans acquire this organism from a wide range of food and water sources as well as during aquatic recreational activities. In the present study, the diversity and distribution of Aeromonas species from freshwater lakes in Malaysia was investigated using glycerophospholipid-cholesterol acyltransferase (GCAT) and RNA polymerase sigma-factor (rpoD) genes for speciation. A total of 122 possible Aeromonas strains were isolated and confirmed to genus level using the API20E system. The clonality of the isolates was investigated using ERIC-PCR and 20 duplicate isolates were excluded from the study. The specific GCAT-PCR identified all isolates as belonging to the genus Aeromonas, in agreement with the biochemical identification. A phylogenetic tree was constructed using the rpoD gene sequence and all 102 isolates were identified as: A. veronii 43%, A. jandaei 37%, A. hydrophila 6%, A. caviae 4%, A. salmonicida 2%, A. media 2%, A. allosaccharophila 1%, A. dhakensis 1% and Aeromonas spp. 4%. Twelve virulence genes were present in the following proportions--exu 96%, ser 93%, aer 87%, fla 83%, enolase 70%, ela 62%, act 54%, aexT 33%, lip 16%, dam 16%, alt 8% and ast 4%, and at least 2 of these genes were present in all 102 strains. The ascV, aexU and hlyA genes were not detected among the isolates. A. hydrophila was the main species containing virulence genes alt and ast either present alone or in combination. It is possible that different mechanisms may be used by each genospecies to demonstrate virulence. In summary, with the use of GCAT and rpoD genes, unambiguous identification of Aeromonas species is possible and provides valuable data on the phylogenetic diversity of the organism.

  19. Phenotypic and Genetic Diversity of Aeromonas Species Isolated from Fresh Water Lakes in Malaysia.

    Directory of Open Access Journals (Sweden)

    Wei Ching Khor

    Full Text Available Gram-negative bacilli of the genus Aeromonas are primarily inhabitants of the aquatic environment. Humans acquire this organism from a wide range of food and water sources as well as during aquatic recreational activities. In the present study, the diversity and distribution of Aeromonas species from freshwater lakes in Malaysia was investigated using glycerophospholipid-cholesterol acyltransferase (GCAT and RNA polymerase sigma-factor (rpoD genes for speciation. A total of 122 possible Aeromonas strains were isolated and confirmed to genus level using the API20E system. The clonality of the isolates was investigated using ERIC-PCR and 20 duplicate isolates were excluded from the study. The specific GCAT-PCR identified all isolates as belonging to the genus Aeromonas, in agreement with the biochemical identification. A phylogenetic tree was constructed using the rpoD gene sequence and all 102 isolates were identified as: A. veronii 43%, A. jandaei 37%, A. hydrophila 6%, A. caviae 4%, A. salmonicida 2%, A. media 2%, A. allosaccharophila 1%, A. dhakensis 1% and Aeromonas spp. 4%. Twelve virulence genes were present in the following proportions--exu 96%, ser 93%, aer 87%, fla 83%, enolase 70%, ela 62%, act 54%, aexT 33%, lip 16%, dam 16%, alt 8% and ast 4%, and at least 2 of these genes were present in all 102 strains. The ascV, aexU and hlyA genes were not detected among the isolates. A. hydrophila was the main species containing virulence genes alt and ast either present alone or in combination. It is possible that different mechanisms may be used by each genospecies to demonstrate virulence. In summary, with the use of GCAT and rpoD genes, unambiguous identification of Aeromonas species is possible and provides valuable data on the phylogenetic diversity of the organism.

  20. Diazotroph diversity in the sea ice, melt ponds and surface waters of the Eurasian Basin of the Central Arctic Ocean

    OpenAIRE

    Fernández-Méndez, Mar; Turk-Kubo, Kendra A.; Rapp, Josephine Z.; Buttigieg, Pier Luigi; Krumpen, Thomas; Jonathan P Zehr; Boetius, Antje

    2016-01-01

    The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which ...

  1. Bacterial diversity in shallow oligotrophic marine benthos and overlying waters: effects of virus infection, containment, and nutrient enrichment.

    Science.gov (United States)

    Hewson, I; Vargo, G A; Fuhrman, J A

    2003-10-01

    Little is known of the factors shaping sediment bacterial communities, despite their high abundance and reports of high diversity. Two factors hypothesized to shape bacterial communities in the water column are nutrient (resource) availability and virus infection. The role these factors play in benthic bacterial diversity was assessed in oligotrophic carbonate-based sediments of Florida Bay (USA). Sediment-water mesocosm enclosures were made from 1-m diameter clear polycarbonate cylinders which were pushed into sediments to approximately 201 cm sediment depth enclosing approximately 80 L of water. Mesocosms were amended each day for 14 d with 10 microM NH4+ and 1 microM PO4(3-). In a second experiment, viruses from a benthic flocculent layer were concentrated and added back to flocculent layer samples which were collected near the mesocosm enclosures. Photosynthesis by microalgae in virus-amended incubations was monitored by pulse-amplitude modulated (PAM) fluorescence. In both experiments, bacterial diversity was estimated using automated rRNA intergenic spacer analysis (ARISA), a high-resolution fingerprinting approach. Initial sediment bacterial operational taxonomic unit (OTU) richness (236 +/- 3) was higher than in the water column (148 +/- 9), where an OTU was detectable when its amplified DNA represented >0.09% of the total amplified DNA. Effects on bacterial diversity and operational taxonomic unit (OTU) richness in nutrient-amended mesocosms may have been masked by the effects of containment, which stimulated OTU richness in the water column, but depressed OTU richness and diversity in sediments. Nutrient addition significantly elevated virus abundance and the ratio of viruses to bacteria (p < 0.05 for both) in the sediments, concomitant with elevated bacterial diversity. However, water column bacterial diversity (in unamended controls) was not affected by nutrient amendments, which may be due to rapid nutrient uptake by sediment organisms or adsorption of

  2. Trace elements affect methanogenic activity and diversity in enrichments from subsurface coal bed produced water.

    Science.gov (United States)

    Unal, Burcu; Perry, Verlin Ryan; Sheth, Mili; Gomez-Alvarez, Vicente; Chin, Kuk-Jeong; Nüsslein, Klaus

    2012-01-01

    Microbial methane from coal beds accounts for a significant and growing percentage of natural gas worldwide. Our knowledge of physical and geochemical factors regulating methanogenesis is still in its infancy. We hypothesized that in these closed systems, trace elements (as micronutrients) are a limiting factor for methanogenic growth and activity. Trace elements are essential components of enzymes or cofactors of metabolic pathways associated with methanogenesis. This study examined the effects of eight trace elements (iron, nickel, cobalt, molybdenum, zinc, manganese, boron, and copper) on methane production, on mcrA transcript levels, and on methanogenic community structure in enrichment cultures obtained from coal bed methane (CBM) well produced water samples from the Powder River Basin, Wyoming. Methane production was shown to be limited both by a lack of additional trace elements as well as by the addition of an overly concentrated trace element mixture. Addition of trace elements at concentrations optimized for standard media enhanced methane production by 37%. After 7 days of incubation, the levels of mcrA transcripts in enrichment cultures with trace element amendment were much higher than in cultures without amendment. Transcript levels of mcrA correlated positively with elevated rates of methane production in supplemented enrichments (R(2) = 0.95). Metabolically active methanogens, identified by clone sequences of mcrA mRNA retrieved from enrichment cultures, were closely related to Methanobacterium subterraneum and Methanobacterium formicicum. Enrichment cultures were dominated by M. subterraneum and had slightly higher predicted methanogenic richness, but less diversity than enrichment cultures without amendments. These results suggest that varying concentrations of trace elements in produced water from different subsurface coal wells may cause changing levels of CBM production and alter the composition of the active methanogenic community.

  3. Trace elements affect methanogenic activity and diversity in enrichments from subsurface coal bed produced water

    Directory of Open Access Journals (Sweden)

    Burcu eÜnal

    2012-05-01

    Full Text Available Microbial methane from coal beds accounts for a significant and growing percentage of natural gas worldwide. Our knowledge of physical and geochemical factors regulating methanogenesis is still in its infancy. We hypothesized that in these closed systems, trace elements (as micronutrients are a limiting factor for methanogenic growth and activity. Trace elements are essential components of enzymes or cofactors of metabolic pathways associated with methanogenesis. This study examined the effects of eight trace elements (iron, nickel, cobalt, molybdenum, zinc, manganese, boron, and copper on methane production, on mcrA transcript levels, and on methanogenic community structure in enrichment cultures obtained from coal bed methane well produced water samples from the Powder River Basin, Wyoming. Methane production was shown to be limited both by a lack of additional trace elements as well as by the addition of an overly concentrated trace element mixture. Addition of trace elements at concentrations optimized for standard media enhanced methane production by 37%. After seven days of incubation, the levels of mcrA transcripts in enrichment cultures with trace element amendment were much higher than in cultures without amendment. Transcript levels of mcrA correlated positively with elevated rates of methane production in supplemented enrichments (R2=0.95. Metabolically-active methanogens, identified by clone sequences of mcrA mRNA retrieved from enrichment cultures, were closely related to Methanobacterium subterraneum and Methanobacterium formicicum. Enrichment cultures were dominated by M. subterraneum and had slightly higher predicted methanogenic richness, but less diversity than enrichment cultures without amendments. These results suggest that varying concentrations of trace elements in produced water from different subsurface coal wells may cause changing levels of coal bed methane production and alter the composition of the active

  4. Trophic status of the Iranian Caspian Sea based on water quality parameters and phytoplankton diversity

    Science.gov (United States)

    Nasrollahzadeh, Hasan Saravi; Din, Zubir Bin; Foong, Swee Yeok; Makhlough, Asieh

    2008-05-01

    The present study attempted to test the applicability of the trophic index (TRIX) for assessing trophic status along the Iranian coast of the Caspian Sea (CS). In order to increase the sensitivity of the TRIX for this area, we defined the range (lower and upper limits) from data collected between 1994 and 2005 which have been used as a reference. Several biological and chemical water quality parameters were determined and compared with the TRIX in order to describe the water quality status of the area. Comparisons were also made on two temporarily and spatially varied trophic status at the study site. Sampling was carried out at 36 stations during Phase I (1996-1997: before the introduction of an alien species Mnemiopsis leidyi, as a background data) while 24 stations were sampled during Phase II in 2005 (after the introduction of the alien species). A Parallel Study (as supplementary data) from 16 smaller scale sampling at shallower sites was also included in the discussion (1994-2005 on 18 transects). The results show that nutrient concentration (DIN, DIP compounds), oxygen (as absolute %) deviation from saturation (aD%O), chlorophyll a and also the Caspian Sea Trophic Index (TRIXCS) increase significantly after the introduction of an alien species ( p<0.01). During Phase I and the Parallel Study, the phytoplankton community was dominated (based on important species index) by Thalassionema nitzschioides, Skeletonema costatum (Chrysophyta) year round but during Phase II, Spirulina laxissma (Cyanophyta ) dominated annually and in autumn, coinciding with the minimum Shannon-Weaver diversity and Evenness indices recorded. Several trophic status indices and indicators were applied and an overall analysis suggested that the area has low trophic level during Phase I and high trophic level during Phase II. During the Parallel Study, low trophic level was recorded during the pre-invasion period and high trophic level for the post-invasion period.

  5. Estimation of diversity and combining abilities in Helianthus annuus L. under water stress and normal conditions.

    Science.gov (United States)

    Saba, M; Khan, F A; Sadaqat, H A; Rana, I A

    2016-10-24

    Sunflower cannot produce high yields under water-limiting conditions. The aim of the present study was to prevent the impediments on yield and to develop varieties with high-yield potential under water scarce conditions. For achieving this objective, it is necessary to detect parents with desirable traits that mainly depend on the action of genes controlling the trait under improvement, combining ability, and genetic makeup of the parents. Heterosis can also be used to pool the desirable genes from genetically divergent varieties and these divergent parents could be detected by molecular studies. Ten tolerant and five susceptible tester lines were selected, crossed, and tested for genetic diversity using simple sequence repeat primers. We identified two parents (A-10.8 and G-60) that showed maximum (46.7%) genetic dissimilarity. On an average 3.1 alleles per locus were detected for twenty pair of primers. Evaluation of mean values revealed that under stress conditions the mean performances of the genotypes were reduced for all traits under study. Parent A-10.8 was consistent as a good general combiner for achene yield per plant under both non-stress and stress conditions. Line A-10.8 in the hybrid A-10.8 x G-60 proved to be a good combiner as it showed negative specific combining ability (SCA) effects for plant height and internodal length and positive SCA effects for head weight, achene yield per plant, and membrane stability index. Valuable information on gene action, combining ability, and heterosis was generated, which could be used in further breeding programs.

  6. Microbial Diversity of Source and Point-of-Use Water in Rural Haiti – A Pyrosequencing-Based Metagenomic Survey

    Science.gov (United States)

    Mukherjee, Nabanita; Bartelli, Debra; Patra, Cyril; Chauhan, Bhavin V.; Dowd, Scot E.

    2016-01-01

    Haiti endures the poorest water and sanitation infrastructure in the Western Hemisphere, where waterborne diseases cause significant morbidity and mortality. Most of these diseases are reported to be caused by waterborne pathogens. In this study, we examined the overall bacterial diversity of selected source and point-of-use water from rural areas in Central Plateau, Haiti using pyrosequencing of 16s rRNA genes. Taxonomic composition of water samples revealed an abundance of Firmicutes phyla, followed by Proteobacteria and Bacteroidetes. A total of 38 bacterial families and 60 genera were identified. The presence of several Klebsiella spp. (tentatively, K. pneumoniae, K. variicola and other Klebsiella spp.) was detected in most water samples. Several other human pathogens such as Aeromonas, Bacillus, Clostridium, and Yersinia constituted significantly higher proportion of bacterial communities in the point-of-use water samples compared to source water. Bacterial genera traditionally associated with biofilm formation, such as Chryseobacterium, Fusobacterium, Prevotella, Pseudomonas were found in the point-of-use waters obtained from water filters or domestic water storage containers. Although the pyrosequencing method utilized in this study did not reveal the viability status of these pathogens, the abundance of genetic footprints of the pathogens in water samples indicate the probable risk of bacterial transmission to humans. Therefore, the importance of appropriate handling, purification, and treatment of the source water needed to be clearly communicated to the communities in rural Haiti to ensure the water is safe for their daily use and intake. PMID:27936055

  7. Microbial Diversity of Source and Point-of-Use Water in Rural Haiti - A Pyrosequencing-Based Metagenomic Survey.

    Science.gov (United States)

    Mukherjee, Nabanita; Bartelli, Debra; Patra, Cyril; Chauhan, Bhavin V; Dowd, Scot E; Banerjee, Pratik

    2016-01-01

    Haiti endures the poorest water and sanitation infrastructure in the Western Hemisphere, where waterborne diseases cause significant morbidity and mortality. Most of these diseases are reported to be caused by waterborne pathogens. In this study, we examined the overall bacterial diversity of selected source and point-of-use water from rural areas in Central Plateau, Haiti using pyrosequencing of 16s rRNA genes. Taxonomic composition of water samples revealed an abundance of Firmicutes phyla, followed by Proteobacteria and Bacteroidetes. A total of 38 bacterial families and 60 genera were identified. The presence of several Klebsiella spp. (tentatively, K. pneumoniae, K. variicola and other Klebsiella spp.) was detected in most water samples. Several other human pathogens such as Aeromonas, Bacillus, Clostridium, and Yersinia constituted significantly higher proportion of bacterial communities in the point-of-use water samples compared to source water. Bacterial genera traditionally associated with biofilm formation, such as Chryseobacterium, Fusobacterium, Prevotella, Pseudomonas were found in the point-of-use waters obtained from water filters or domestic water storage containers. Although the pyrosequencing method utilized in this study did not reveal the viability status of these pathogens, the abundance of genetic footprints of the pathogens in water samples indicate the probable risk of bacterial transmission to humans. Therefore, the importance of appropriate handling, purification, and treatment of the source water needed to be clearly communicated to the communities in rural Haiti to ensure the water is safe for their daily use and intake.

  8. Spatio-temporal distribution of phytoplankton in the Danjiangkou Reservoir, a water source area for the South-to-North Water Diversion Project (Middle Route), China

    Institute of Scientific and Technical Information of China (English)

    YIN Dacong; ZHENG Lingling; SONG Lirong

    2011-01-01

    One of the water source areas of the South-to-North Water Diversion Project is the Danjiangkou Reservoir (DJKR). To understand seasonal variation in phytoplankton composition, abundance and distribution in the DJKR area before water diversion, as well as to estimate potential risks of water quality after water diversion, we conducted an investigation on phytoplankton in the DJKR from August 2008 to May 2009. The investigation included 10 sampling sites, each with four depths of 0.5, 5, 10, and 20 m. In this study, 117 taxa belonging to 76 genera were identified, consisting of diatoms (39 taxa), green algae (47 taxa), blue-green algae (19 taxa), and others (12 taxa). Annual average phytoplankton abundance was 2.01xl06 ind./L, and the highest value was 14.72 x 106 ind/L (at site 3 in August 2008). Phytoplankton abundance in front of the Danjiangkou Dam (DJKD) was higher than that of the Danjiang Reservoir Basin. Phytoplankton distribution showed a vertical declining trend from 0.5 m to 20 m at most sites in August 2008 (especially at sites of 1, 2, 4 and 10), but no distinct pattern in other sampling months. In December 2008 and March 2009, Stephanodiscus sp. was the most abundant species, amounting to 55.23% and 72.34%, respectively. We propose that high abundance of Stephanodiscus sp. may have contributed greatly to the frequent occurrence of Stephanodiscus sp. blooms in middle-low reaches of the Hanjiang River during the early spring of 2009. In comparison with previous studies conducted from 1992 to 2006, annual average phytoplankton density, green algae and blue-green algae species, as well as major nutrient concentrations increased, while phytoplankton diversity indices declined. This indicates a gradual decline in water quality. More research should be conducted and countermeasures taken to prevent further deterioration of water quality in the DJKR.

  9. Bacterial Diversity Across a Turbidite-Stranded Sediment-Water Interface, La Jolla Canyon, CA

    Science.gov (United States)

    Harrison, B. K.; Flood, B.; Myrbo, A.; Bailey, J.

    2016-12-01

    The emplacement of gravity-driven sediment flows imposes a significant physical and geochemical impact on underlying sediment and microbial communities. Although previous studies have established lasting mineralogical (e.g., McKay and Pederson, 2014) and biological signatures (e.g., Anschutz et al., 2002) of turbidite deposition, the response of prokaryotes within and beneath debris flows remains poorly constrained. Both bacterial cells associated with the underlying sediment and allocthonous material must respond to substantially altered selective pressures. As a consequence, turbidites and underlying sediments provide an exceptional opportunity to examine 1) microbial community response to sedimentation 2) preservation and identification of microbial dispersal mechanisms. We collected Illumina MiSeq sequence libraries across an intact marine turbidite boundary at 25cm sediment depth in La Jolla canyon off the coast of California. 16S rRNA gene signatures of relict and active bacterial populations exhibit persistent differences attributable to turbidite deposition. In particular, the sedimentary boundary is sharply demarcated at the cm scale by the diversity and abundance of Chloroflexi, Planctomycetes, and Actinobacteria. Variations in the abundance of putative dissimilatory sulfate-reducing Deltaproteobacteria across the stranded sediment-water interface reflect persistent turbidite-induced changes to the geochemical environment. This work raises the possibility that abrupt sedimentological events may alter the microbial community in a manner that persists with burial.

  10. Diversity and physiology of marine lignicolous fungi in Arctic waters: a preliminary account

    Directory of Open Access Journals (Sweden)

    Ka-Lai Pang

    2011-01-01

    Full Text Available Information on the diversity of marine fungi in polar environments is lacking, especially marine fungi colonizing wood. During visits to Tromsø and Longyearbyen, Norway, drift and trapped wood was collected to provide a preliminary account of lignicolous marine fungi in Arctic waters. Six marine fungi were recorded from 24 and 27 samples of wood from Tromsø and Longyearbyen, respectively. Among these, four marine fungi new to science were identified from wood collected at Longyearbyen. To shed light on the ecological role of this group of fungi in the Arctic, a physiological study of one of the collected fungi, Havispora longyearbyenensis, was conducted. H. longyearbyenensis grew at 4 °C, 10 °C, 15 °C and 20 °C in all salinities tested (0 0/00, 17 0/00, 34 0/00. However, growth was significantly reduced at 4 °C and 0 0/00 salinity. The optimal condition for growth of H. longyearbyenensis was at 20 °C in all salinities tested.

  11. 3D Finite Element Analysis of TBM Water Diversion Tunnel Segment Coupled with Seepage Field

    Institute of Scientific and Technical Information of China (English)

    钟登华; 胡能明; 程正飞; 吕鹏; 佟大威

    2016-01-01

    In most studies of tunnel boring machine(TBM)tunnelling, the groundwater pressure was not consid-ered, or was simplified and exerted on the boundary of lining structure. Meanwhile, the leakage, which mainly oc-curs in the segment joints, was often ignored in the relevant studies of TBM tunnelling. Additionally, the geological models in these studies were simplified to different extents, and mostly were simplified as homogenous bodies. Considering the deficiencies above, a 3D refined model of the surrounding rock of a tunnel is firstly established using NURBS-TIN-BReP hybrid data structure in this paper. Then the seepage field of the surrounding rock con-sidering the leakage in the segment joints is simulated. Finally, the stability of TBM water diversion tunnel is stud-ied coupled with the seepage simulation, to analyze the stress-strain conditions, the axial force and the bending moment of tunnel segment considering the leakage in the segment joints. The results illustrate that the maximum radial displacement, the minimum principal stress, the maximum principal stress and the axial force of segment lining considering the seepage effect are all larger than those disregarding the seepage effect.

  12. Factors Influencing Bacterial Diversity and Community Composition in Municipal Drinking Waters in the Ohio River Basin, USA

    Science.gov (United States)

    Stanish, Lee F.; Hull, Natalie M.; Robertson, Charles E.; Harris, J. Kirk; Stevens, Mark J.; Spear, John R.; Pace, Norman R.

    2016-01-01

    The composition and metabolic activities of microbes in drinking water distribution systems can affect water quality and distribution system integrity. In order to understand regional variations in drinking water microbiology in the upper Ohio River watershed, the chemical and microbiological constituents of 17 municipal distribution systems were assessed. While sporadic variations were observed, the microbial diversity was generally dominated by fewer than 10 taxa, and was driven by the amount of disinfectant residual in the water. Overall, Mycobacterium spp. (Actinobacteria), MLE1-12 (phylum Cyanobacteria), Methylobacterium spp., and sphingomonads were the dominant taxa. Shifts in community composition from Alphaproteobacteria and Betaproteobacteria to Firmicutes and Gammaproteobacteria were associated with higher residual chlorine. Alpha- and beta-diversity were higher in systems with higher chlorine loads, which may reflect changes in the ecological processes structuring the communities under different levels of oxidative stress. These results expand the assessment of microbial diversity in municipal distribution systems and demonstrate the value of considering ecological theory to understand the processes controlling microbial makeup. Such understanding may inform the management of municipal drinking water resources. PMID:27362708

  13. Factors Influencing Bacterial Diversity and Community Composition in Municipal Drinking Waters in the Ohio River Basin, USA.

    Directory of Open Access Journals (Sweden)

    Lee F Stanish

    Full Text Available The composition and metabolic activities of microbes in drinking water distribution systems can affect water quality and distribution system integrity. In order to understand regional variations in drinking water microbiology in the upper Ohio River watershed, the chemical and microbiological constituents of 17 municipal distribution systems were assessed. While sporadic variations were observed, the microbial diversity was generally dominated by fewer than 10 taxa, and was driven by the amount of disinfectant residual in the water. Overall, Mycobacterium spp. (Actinobacteria, MLE1-12 (phylum Cyanobacteria, Methylobacterium spp., and sphingomonads were the dominant taxa. Shifts in community composition from Alphaproteobacteria and Betaproteobacteria to Firmicutes and Gammaproteobacteria were associated with higher residual chlorine. Alpha- and beta-diversity were higher in systems with higher chlorine loads, which may reflect changes in the ecological processes structuring the communities under different levels of oxidative stress. These results expand the assessment of microbial diversity in municipal distribution systems and demonstrate the value of considering ecological theory to understand the processes controlling microbial makeup. Such understanding may inform the management of municipal drinking water resources.

  14. [Investigation of the microbial diversity and structure of biological activated carbon from different sources in drinking water treatment process].

    Science.gov (United States)

    Du, Er-Deng; Zheng, Lu; Feng, Xin-Xin; Gao, Nai-Yun

    2014-11-01

    Restriction fragment length polymorphism (RFLP) technology was used to investigate the microbial diversity and structure of biological activated carbon (BAC) from different sources in drinking water advanced treatment process. Diversity indices of samples A, B and C, with relatively high tannic acid and humic acid adsorption capacity, were close to each other, which meant higher microbial diversity. However, samples D and E had relatively lower diversity indices with the low tannic acid and humic acid adsorption capacity. There were five species including β-Proteobacteria, α-Proteobacteria, Planctomycetes, γ-Proteobacteria, Bacteroidetes in the phylogenetic tree of BAC samples. Among them, β-Proteobacteria and α-Proteobacteria were the dominant microbial species in these BAC samples, which played an important role in organic matter removal. Planctomycetes, γ-Proteobacteria, and Bacteroidetes were the non-dominant microbial species. Bacteroidetes only existed in samples A, B, C and D, while did not occur in sample E. The BAC samples with the higher tannic acid and humic acid adsorption capacity had higher microbial diversity. This research should deepen the understanding of microbial community in BAC, and provide a theoretical basis for the safety of drinking water.

  15. Are fire, soil fertility and toxicity, water availability, plant functional diversity, and litter decomposition related in a Neotropical savanna?

    Science.gov (United States)

    Carvalho, Gustavo Henrique; Batalha, Marco Antônio; Silva, Igor Aurélio; Cianciaruso, Marcus Vinicius; Petchey, Owen L

    2014-07-01

    Understanding how biodiversity and ecosystem functioning respond to changes in the environment is fundamental to the maintenance of ecosystem function. In realistic scenarios, the biodiversity-ecosystem functioning path may account for only a small share of all factors determining ecosystem function. Here, we investigated the strength to which variations in environmental characteristics in a Neotropical savanna affected functional diversity and decomposition. We sought an integrative approach, testing a number of pairwise hypotheses about how the environment, biodiversity, and functioning were linked. We used structural equation modelling to connect fire frequency, soil fertility, exchangeable Al, water availability, functional diversity of woody plants, tree density, tree height, and litter decomposition rates in a causal chain. We found significant effects of soil nutrients, water availability, and Al on functional diversity and litter decomposition. Fire did not have a significant direct effect on functional diversity or litter decomposition. However, fire was connected to both variables through soil fertility. Functional diversity did not influence rates of litter decomposition. The mediated effects that emerged from pairwise interactions are encouraging not only for predicting the functional consequences of changes in environmental variables and biodiversity, but also to caution against predictions based on only environmental or only biodiversity change.

  16. Driving factors for runoff decline in the Upper Hanjiang basin, a major water source for the South-to-North Water Diversion Project in China

    OpenAIRE

    Zhang, S.; Yang, D.; Xu, X.

    2015-01-01

    With dramatic changes in climate and land-cover patterns around the world, it is of great significance to evaluate the corresponding influence on runoff change as water resources have become a strategic resource. We analysed the runoff change driven by landscape change and climate variation in Hanjiang River basin, which is the water source area of the central route of the South-to-North Water Diversion Project in China. Results show that the runoff decreased greatly from 1960 to 2012 in all ...

  17. Late Permian marine ecosystem collapse began in deeper waters: evidence from brachiopod diversity and body size changes.

    Science.gov (United States)

    He, W-H; Shi, G R; Twitchett, R J; Zhang, Y; Zhang, K-X; Song, H-J; Yue, M-L; Wu, S-B; Wu, H-T; Yang, T-L; Xiao, Y-F

    2015-03-01

    Analysis of Permian-Triassic brachiopod diversity and body size changes from different water depths spanning the continental shelf to basinal facies in South China provides insights into the process of environmental deterioration. Comparison of the temporal changes of brachiopod diversity between deepwater and shallow-water facies demonstrates that deepwater brachiopods disappeared earlier than shallow-water brachiopods. This indicates that high environmental stress commenced first in deepwater settings and later extended to shallow waters. This environmental stress is attributed to major volcanic eruptions, which first led to formation of a stratified ocean and a chemocline in the outer shelf and deeper water environments, causing the disappearance of deep marine benthos including brachiopods. The chemocline then rapidly migrated upward and extended to shallow waters, causing widespread mass extinction of shallow marine benthos. We predict that the spatial and temporal patterns of earlier onset of disappearance/extinction and ecological crisis in deeper water ecosystems will be recorded during other episodes of rapid global warming.

  18. Development of a Nucleic Acid Extraction Procedure for Simultaneous Recovery of DNA and RNA from Diverse Microbes in Water

    Directory of Open Access Journals (Sweden)

    Vincent R. Hill

    2015-05-01

    Full Text Available Drinking and environmental water samples contain a diverse array of constituents that can interfere with molecular testing techniques, especially when large volumes of water are concentrated to the small volumes needed for effective molecular analysis. In this study, a suite of enteric viruses, bacteria, and protozoan parasites were seeded into concentrated source water and finished drinking water samples, in order to investigate the relative performance of nucleic acid extraction techniques for molecular testing. Real-time PCR and reverse transcription-PCR crossing threshold (CT values were used as the metrics for evaluating relative performance. Experimental results were used to develop a guanidinium isothiocyanate-based lysis buffer (UNEX buffer that enabled effective simultaneous extraction and recovery of DNA and RNA from the suite of study microbes. Procedures for bead beating, nucleic acid purification, and PCR facilitation were also developed and integrated in the protocol. The final lysis buffer and sample preparation procedure was found to be effective for a panel of drinking water and source water concentrates when compared to commercial nucleic acid extraction kits. The UNEX buffer-based extraction protocol enabled PCR detection of six study microbes, in 100 L finished water samples from four drinking water treatment facilities, within three CT values (i.e., within 90% difference of the reagent-grade water control. The results from this study indicate that this newly formulated lysis buffer and sample preparation procedure can be useful for standardized molecular testing of drinking and environmental waters.

  19. The effects of water diversion and climate change on hydrological alteration and temperature regime of karst rivers in central Croatia.

    Science.gov (United States)

    Zganec, Krešimir

    2012-09-01

    Karst rivers in Croatia have been heavily dammed in the past. However, long-term impacts of dams, water diversion and climate change on karst rivers in Croatia have rarely been examined. This study analyzes long-term trends of hydrological and temperature conditions, prior to closure of new large dam, in five connected karst rivers of central Croatia: the sinking rivers Gornja Dobra and Zagorska Mrežnica that have underground connections with the Gojačka Dobra, Tounjčica and Mrežnica Rivers. It was established that hydrological conditions of these rivers have been greatly changed after the Gojak HPP, located at spring of Gojačka Dobra, became operational in 1959. Water diversion from the reservoirs on Zagorska Mrežnica and Gornja Dobra to the Gojak HPP has increased mean annual discharge (52-106%), causing great subdaily fluctuations and overall modification of natural flow regime along the whole course of Gojačka Dobra. By cutting the connection between Zagorska Mrežnica and Tounjčica, water diversion has caused a reduction of mean annual discharges of the Tounjčica (-60%) and Mrežnica (-29%) Rivers. Analyses of long-term trends in water temperature over the last 50 years have revealed significant positive trends in average annual temperature at three gauging stations on three rivers with increase of 0.17, 0.44 and 0.48°C per decade and climate change as the primary cause. The highest significant increasing trend was established at the lower course of Mrežnica where discharge was reduced by water diversion. Mitigation measures for the improvement of hydrological conditions of affected rivers and underground systems are proposed and discussed.

  20. A preliminary investigation on genetic diversity of Sousa chinensis in the Pearl River Estuary and Xiamen of Chinese waters

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    In this study, the mitochondrial DNA (mtDNA) control region and the mitochondrial cytochrome b gene of stranded Indo-Pacific humpback dolphin (Sousa chinensis) samples from the Pearl River Estuary and Xiamen waters were sequenced and analyzed. The result of mtDNA control region revealed 34 variable sites and four unique haplotypes (named as A, B, C and D) identified among the total samples from these two water areas, and the most common haplotype (A) was shared by 75% of the dolphins sampled from the two water areas. The haplotypic diversity (h) was 0.455 and the nucleotide diversity (π) was 0.0088. The phylogenetic analysis showed that the haplotype A, C, and D were closely related, but the haplotype B (unique for XM01 from Xiamen) was far from the other three. By scanning cytochrome b fragments, two haplotypes (A and B) were identified in these two water areas, and the most common haplotype (A) was shared by 91.67% individuals, while XM01 from Xiamen as the only exception. The date suggest that there is a possibility of gene exchange between the two populations in the Pearl River Estuary and Xiamen waters, and there possibly exists a unique maternal lineage in Xiamen waters.

  1. Interactive effects of water diversion and climate change for juvenile chinook salmon in the lemhi river basin (USA.).

    Science.gov (United States)

    Walters, Annika W; Bartz, Krista K; McClure, Michelle M

    2013-12-01

    The combined effects of water diversion and climate change are a major conservation challenge for freshwater ecosystems. In the Lemhi Basin, Idaho (U.S.A.), water diversion causes changes in streamflow, and climate change will further affect streamflow and temperature. Shifts in streamflow and temperature regimes can affect juvenile salmon growth, movement, and survival. We examined the potential effects of water diversion and climate change on juvenile Chinook salmon (Oncorhynchus tshawytscha), a species listed as threatened under the U.S. Endangered Species Act (ESA). To examine the effects for juvenile survival, we created a model relating 19 years of juvenile survival data to streamflow and temperature and found spring streamflow and summer temperature were good predictors of juvenile survival. We used these models to project juvenile survival for 15 diversion and climate-change scenarios. Projected survival was 42-58% lower when streamflows were diverted than when streamflows were undiverted. For diverted streamflows, 2040 climate-change scenarios (ECHO-G and CGCM3.1 T47) resulted in an additional 11-39% decrease in survival. We also created models relating habitat carrying capacity to streamflow and made projections for diversion and climate-change scenarios. Habitat carrying capacity estimated for diverted streamflows was 17-58% lower than for undiverted streamflows. Climate-change scenarios resulted in additional decreases in carrying capacity for the dry (ECHO-G) climate model. Our results indicate climate change will likely pose an additional stressor that should be considered when evaluating the effects of anthropogenic actions on salmon population status. Thus, this type of analysis will be especially important for evaluating effects of specific actions on a particular species. Efectos Interactivos de la Desviación del Agua y el Cambio Climático en Individuos Juveniles de Salmón Chinook en la Cuenca del Río Lemhi (E.U.A.).

  2. Diversity of culturable Gram-negative bacteria isolated from irrigation water of two rice crop regions in Southern Brazil.

    Science.gov (United States)

    Reche, Maria Helena Lima Ribeiro; Reali, Catiusca; Pittol, Michele; de Athayde Saul, Danilo; Macedo, Vera Regina Mussoi; Valiati, Victor Hugo; Machado, Vilmar; Fiuza, Lidia Mariana

    2016-06-01

    In this study, we assessed the diversity of Gram-negative bacteria found in water used for irrigation of rice crops in two growing areas of southern Brazil. Samples were collected from the main irrigation channel and field drain area. Twenty-two bacterial species were found in Cachoeirinha and 28 in Camaquã. In both areas, the most frequent bacterial families were Enterobacteriaceae and Aeromonadaceae. Differences in microbial diversity were observed in both study areas. Thirty-five Gram-negative species were identified; however, only 15 were common in both locations. In addition, there were found pathogenic and drug-resistant species, such as Acinetobacter sp., Brucella spp., and Chryseobacterium meningosepticum. This study demonstrates the existence of a number of pathogenic species in aquatic ecosystems analyzed in three consecutive crop years, especially water used for rice production.

  3. System identification of channel roughness for Mid-Route Project of South-to-North Water Diversion

    Institute of Scientific and Technical Information of China (English)

    Yang Kailin; Wang Yisen

    2013-01-01

    This paper presents a new method for the system identification of the channel roughness for the water di-version projects. According to the principle of hydraulics,the function relationship among channel roughness n, roughness height ks and hydraulic radius R is established,and then a linear model is deduced by means of the mathematical transformation to make use of the least square method for identification. Finally,based on the proto-type observation data from the South-to-North Water Diversion Project and considering the influence of channel lengths,cross-section shapes and bottom slopes,etc,a universal formula is obtained for calculation of channel roughness by the system identification.

  4. Genetic Diversity and Temporal Variation in the Cyanophage Community Infecting Marine Synechococcus Species in Rhode Island's Coastal Waters

    OpenAIRE

    Marston, Marcia F.; Sallee, Jennifer L.

    2003-01-01

    The cyanophage community in Rhode Island's coastal waters is genetically diverse and dynamic. Cyanophage abundance ranged from over 104 phage ml−1 in the summer months to less then 102 phage ml−1 during the winter months. Thirty-six distinct cyanomyovirus g20 genotypes were identified over a 3-year sampling period; however, only one to nine g20 genotypes were detected at any one sampling date. Phylogenetic analyses of g20 sequences revealed that the Rhode Island cyanomyoviral isolates fall in...

  5. Soil CO2 efflux and water use efficiency across diverse cover types in southern Appalachian hardwood forests

    Science.gov (United States)

    Ruba C. Bilal; John R. Seiler; Brian D. Strahm; John A. Peterson

    2016-01-01

    We are investigating biogeochemical cycling in a mixed hardwood forest in the Ridge and Valley physiographic province in Montgomery County, Virginia. The broad aim of the study is to understand how carbon, water and nutrient cycles vary among diverse stand types in a relatively small spatial area. The specific objectives here are to determine patterns in soil CO2...

  6. Analysis of human mitochondrial DNA sequences from fecally polluted environmental waters as a tool to study population diversity

    Directory of Open Access Journals (Sweden)

    Vikram Kapoor

    2017-05-01

    Full Text Available Mitochondrial signature sequences have frequently been used to study human population diversity around the world. Traditionally, this requires obtaining samples directly from individuals which is cumbersome, time consuming and limited to the number of individuals that participated in these types of surveys. Here, we used environmental DNA extracts to determine the presence and sequence variability of human mitochondrial sequences as a means to study the diversity of populations inhabiting in areas nearby a tropical watershed impacted with human fecal pollution. We used high-throughput sequencing (Illumina and barcoding to obtain thousands of sequences from the mitochondrial hypervariable region 2 (HVR2 and determined the different haplotypes present in 10 different water samples. Sequence analyses indicated a total of 19 distinct variants with frequency greater than 5%. The HVR2 sequences were associated with haplogroups of West Eurasian (57.6%, Sub-Saharan African (23.9%, and American Indian (11% ancestry. This was in relative accordance with population census data from the watershed sites. The results from this study demonstrates the potential value of mitochondrial sequence data retrieved from fecally impacted environmental waters to study the population diversity of local municipalities. This environmental DNA approach may also have other public health implications such as tracking background levels of human mitochondrial genes associated with diseases. It may be possible to expand this approach to other animal species inhabiting or using natural water systems.

  7. 引滦输水污染物对于桥水库水环境的影响%Effects of water pollutants from Luanhe-Tianjin water diversion on water environment of Yuqiao Reservoir

    Institute of Scientific and Technical Information of China (English)

    张庆强; 周潮晖; 王旭丹; 王立亚; 马金玲

    2014-01-01

    In this study , the characteristic water pollutants flowing into the Yuqiao Reservoir from the Luanhe-Tianjin Water Diversion during water diversion and non-water diversion periods were studied , and the effects of suspended matter , total nitrogen , and total phosphorus on the water environment of the reservoir were analyzed . The results show that the main factors influencing the reservoir ’ s water environment were total nitrogen and total phosphorus , which came from the upstream reservoir .There were large amounts of suspended matter and heavy metals in the water during the diversion , which mainly came from the tailings and deposits on both sides of the water diversion route .As the suspended matter and heavy metals were deposited in large amounts before they entered the Yuqiao Reservoir , they had an insignificant effect on the water environment of the reservoir .%对引滦输水期及非输水期引滦沿线入库水体污染物研究,分析水体中悬浮物、TN、TP等污染物对于桥水库水环境质量产生的影响。结果表明:对于桥水库的水环境产生影响的主要水质指标为TN、TP,其主要来源为引滦输水的上游水库;悬浮物及重金属在引滦输水沿线水体中含量较大,主要来源于沿线两岸的铁矿砂及选砂堆积物,但进入于桥水库前沉积量较大,对水库水环境影响较小。

  8. SOIL AND WATER MICROORGANISM DIVERSITY OF MANGROVE FOREST OF TELUK KELUMPANG, SELAT LAUT AND SELAT SEBUKU NATURAL RESERVE

    Directory of Open Access Journals (Sweden)

    Wawan Halwany

    2015-12-01

    Full Text Available Mangrove is a unique ecosystem that has complex biotic and abiotic components. Soil and water microorganisms have function as decomposer in mangrove forest ecosystem. This paper studies the soil and water microorganisms' diversity, their potential, function in ecosystem and their role as environmental parameters in mangrove area of Teluk Kelumpang, Selat Laut and Selat Sebuku Natural Reserve (Kelautku Natural Reserve. Data of soil and water microorganisms were recorded from soil and water samplings then analyzed in the laboratory. Results show that benthos in Selat Sebuku figure the highest diversity index. Anadara granosa is one of the common benthos found in Selat Sebuku. In contrary the phytoplankton in Selat Sebuku is the lowest value compared to the other two locations, due to the settlements in the locations and it was suspected that Selat Sebuku has a relatively larger wave exposure than the two other locations. In addition, input of organic matters from the settlements in Teluk Kelumpang and Selat Laut is also effected by the growth of phytoplankton. Cyanophyta found in Teluk Kelumpang and Selat Laut was genera of Oscillatoria that showed high tolerance genera to the environment conditions.

  9. Analysis of the diversity of water kefir microbiota by culture-dependent and -independent approaches

    OpenAIRE

    Gulitz, Anna Jana

    2014-01-01

    Water kefir is a traditional fermented beverage based on a sucrose solution with different dried fruits. In this work the microbiome of water kefir and the dynamic of the water kefir consortium depending on the cultivation conditions was analyzed by culture-dependent and –independent methods. Microorganisms important for the water kefir grain formation and for the typical beverage characteristics were identified. The most abundant species were Lactobacillus nagelii, Lb. hordei, Leuconostoc me...

  10. Diverse patterns of stored water use among saplings in seasonally dry tropical forests.

    Science.gov (United States)

    Wolfe, Brett T; Kursar, Thomas A

    2015-12-01

    Tree species in seasonally dry tropical forests likely vary in their drought-survival mechanisms. Drought-deciduousness, which reduces water loss, and low wood density, which may permit dependence on stored water, are considered key traits. For saplings of six species at two distinct sites, we studied these and two associated traits: the seasonal amount of water released per stem volume ("water released") and the hydraulic capacitance of the stem (C). Two deciduous species with low stem density, Cavanillesia platanifolia and Bursera simaruba, had high C and high dry-season stem water potential (Ψ(stem)), but differed in dry-season water released. C. platanifolia did not use stored water during the dry season whereas B. simaruba, in a drier forest, released stored water. In both, water released was highest while flushing leaves, suggesting that stored water supports leaf flushing. In contrast, two deciduous species with intermediate stem density, Annona hayesii and Genipa americana, had intermediate C, low dry-season Ψ(stem), and high seasonal change in water released. Meanwhile, two evergreen species with intermediate stem density, Cojoba rufescens and Astronium graveolens, had relatively low C, low dry-season Ψ(stem), and intermediate seasonal change in water released. Thus, at least three, distinct stored-water-use strategies were observed. Additionally, bark relative water content (RWC) decreased along with Ψ(stem) during the dry season while xylem RWC did not change, suggesting that bark-stored water buffers Ψ(stem) seasonally. Together these results suggest that seasonal use of stored water and change in Ψ(stem) are associated with functional groups that are characterized by combinations of deciduousness and stem density.

  11. Microbial biogeography of drinking water: patterns in phylogenetic diversity across space and time.

    Science.gov (United States)

    Roeselers, Guus; Coolen, Jordy; van der Wielen, Paul W J J; Jaspers, Marco C; Atsma, Adrie; de Graaf, Bendert; Schuren, Frank

    2015-07-01

    In this study, we collected water from different locations in 32 drinking water distribution networks in the Netherlands and analysed the spatial and temporal variation in microbial community composition by high-throughput sequencing of 16S rRNA gene amplicons. We observed that microbial community compositions of raw source and processed water were very different for each distribution network sampled. In each network, major differences in community compositions were observed between raw and processed water, although community structures of processed water did not differ substantially from end-point tap water. End-point water samples within the same distribution network revealed very similar community structures. Network-specific communities were shown to be surprisingly stable in time. Biofilm communities sampled from domestic water metres varied distinctly between households and showed no resemblance to planktonic communities within the same distribution networks. Our findings demonstrate that high-throughput sequencing provides a powerful and sensitive tool to probe microbial community composition in drinking water distribution systems. Furthermore, this approach can be used to quantitatively compare the microbial communities to match end-point water samples to specific distribution networks. Insight in the ecology of drinking water distribution systems will facilitate the development of effective control strategies that will ensure safe and high-quality drinking water.

  12. The diversity and structure of marine protists in the coastal waters of China revealed by morphological observation and 454 pyrosequencing

    Science.gov (United States)

    Liu, Yun; Song, Shuqun; Chen, Tiantian; Li, Caiwen

    2017-04-01

    Pyrosequencing of the 18S rRNA gene has been widely adopted to study the eukaryotic diversity in various types of environments, and has an advantage over traditional morphology methods in exploring unknown microbial communities. To comprehensively assess the diversity and community composition of marine protists in the coastal waters of China, we applied both morphological observations and high-throughput sequencing of the V2 and V3 regions of 18S rDNA simultaneously to analyze samples collected from the surface layer of the Yellow and East China Seas. Dinoflagellates, diatoms and ciliates were the three dominant protistan groups as revealed by the two methods. Diatoms were the first dominant protistan group in the microscopic observations, with Skeletonema mainly distributed in the nearshore eutrophic waters and Chaetoceros in higher temperature and higher pH waters. The mixotrophic dinoflagellates, Gymnodinium and Gyrodinium, were more competitive in the oligotrophic waters. The pyrosequencing method revealed an extensive diversity of dinoflagellates. Chaetoceros was the only dominant diatom group in the pyrosequencing dataset. Gyrodinium represented the most abundant reads and dominated the offshore oligotrophic protistan community as they were in the microscopic observations. The dominance of parasitic dinoflagellates in the pyrosequencing dataset, which were overlooked in the morphological observations, indicates more attention should be paid to explore the potential role of this group. Both methods provide coherent clustering of samples. Nutrient levels, salinity and pH were the main factors influencing the distribution of protists. This study demonstrates that different primer pairs used in the pyrosequencing will indicate different protistan community structures. A suitable marker may reveal more comprehensive composition of protists and provide valuable information on environmental drivers.

  13. Effectiveness of a redesigned water diversion using rock vortex weirs to enhance longitudinal connectivity for small Salmonids

    Science.gov (United States)

    Martens, Kyle D.; Connolly, Patrick J.

    2010-01-01

    For nearly 100 years, water diversions have affected fish passage in Beaver Creek, a tributary of the lower Methow River in north-central Washington State. From 2000 to 2004, four dam-style water diversions were replaced with a series of rock vortex weirs (RVWs). The weirs were designed to allow fish passage while maintaining the ability to divert water into irrigation canals. We observed the new appearance of three species (juvenile Chinook salmon Oncorhynchus tshawytscha, juvenile coho salmon O. kisutch, and mountain whitefish Prosopium williamsoni) upstream of the RVWs, indicating successful restoration of longitudinal connectivity. We used passive integrated transponder (PIT) tags and instream PIT tag interrogation systems during 2004–2007 to evaluate upstream passage of small salmonids (<240 mm fork length) through one series of RVWs. We documented 109 upstream passage events by small salmonids through the series of RVWs; most of the events (81%) involved passage of rainbow trout O. mykiss or juvenile steelhead (anadromous rainbow trout). Small rainbow trout or steelhead ranging from 86 to 238 mm (adjusted fork length) were able to pass upstream through the RVWs, although a delay in fish passage at discharges below 0.32 m3/s was detected in comparison with nearby control sections.

  14. Diverse arsenic- and iron-cycling microbial communities in arsenic-contaminated aquifers used for drinking water in Bangladesh.

    Science.gov (United States)

    Hassan, Zahid; Sultana, Munawar; van Breukelen, Boris M; Khan, Sirajul I; Röling, Wilfred F M

    2015-04-01

    Subsurface removal of arsenic by injection with oxygenated groundwater has been proposed as a viable technology for obtaining 'safe' drinking water in Bangladesh. While the oxidation of ferrous iron to solid ferric iron minerals, to which arsenic adsorbs, is assumed to be driven by abiotic reactions, metal-cycling microorganisms may potentially affect arsenic removal. A cultivation-independent survey covering 24 drinking water wells in several geographical regions in Bangladesh was conducted to obtain information on microbial community structure and diversity in general, and on specific functional groups capable of the oxidation or reduction of arsenic or iron. Each functional group, targeted by either group-specific 16S rRNA or functional gene amplification, occurred in at least 79% of investigated samples. Putative arsenate reducers and iron-oxidizing Gallionellaceae were present at low diversity, while more variation in potentially arsenite-oxidizing microorganisms and iron-reducing Desulfuromonadales was revealed within and between samples. Relations between community composition on the one hand and hydrochemistry on the other hand were in general not evident, apart from an impact of salinity on iron-cycling microorganisms. Our data suggest widespread potential for a positive contribution of arsenite and iron oxidizers to arsenic removal upon injection with oxygenated water, but also indicate a potential risk for arsenic re-mobilization by anaerobic arsenate and iron reducers once injection is halted. © FEMS 2015. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  15. Threats of habitat and water-quality degradation to mussel diversity in the Meramec River Basin, Missouri, USA

    Science.gov (United States)

    Hinck, Jo Ellen; Ingersoll, Christopher G.; Wang, Ning; Augspurger, Tom; Barnhart, M. Christopher; McMurray, Stephen E.; Roberts, Andrew D.; Schrader, Lynn

    2011-01-01

    The Meramec River Basin in east-central Missouri is an important stronghold for native freshwater mussels (Order: Unionoida) in the United States. Whereas the basin supports more than 40 mussel species, previous studies indicate that the abundance and distribution of most species are declining. Therefore, resource managers have identified the need to prioritize threats to native mussel populations in the basin and to design a mussel monitoring program. The objective of this study was to identify threats of habitat and water-quality degradation to mussel diversity in the basin. Affected habitat parameters considered as the main threats to mussel conservation included excess sedimentation, altered stream geomorphology and flow, effects on riparian vegetation and condition, impoundments, and invasive non-native species. Evaluating water-quality parameters for conserving mussels was a main focus of this study. Mussel toxicity data for chemical contaminants were compared to national water quality criteria (NWQC) and Missouri water quality standards (MWQS). However, NWQC and MWQS have not been developed for many chemical contaminants and some MWQS may not be protective of native mussel populations. Toxicity data indicated that mussels are sensitive to ammonia, copper, temperature, certain pesticides, pharmaceuticals, and personal care products; these compounds were identified as the priority water-quality parameters for mussel conservation in the basin. Measures to conserve mussel diversity in the basin include expanding the species and life stages of mussels and the list of chemical contaminants that have been assessed, establishing a long term mussel monitoring program that measures physical and chemical parameters of high priority, conducting landscape scale modeling to predict mussel distributions, determining sublethal effects of primary contaminants of concern, deriving risk-based guidance values for mussel conservation, and assessing the effects of wastewater

  16. Assessment of Wetland Water Quality and Avian Diversity of a Human-Modified Floodplain Wetland on River Yamuna

    Directory of Open Access Journals (Sweden)

    Upma MANRAL

    2013-02-01

    Full Text Available Okhla Bird Sanctuary (OBS is an Important Bird Area, which comes under the protected area network of Uttar Pradesh with one-third area lying in the state of Delhi (India. OBS has widest flood plains along the Delhi stretch of river Yamuna and is important in conserving the ecological wealth of floodplains of the river. Rapid urbanization and industrialization and discharge of untreated wastewater into the river have resulted in deteriorated water quality. The present study focused on assessment of water quality, aquatic flora and avifaunal diversity in the OBS. Water quality was analyzed following methods of APHA. For vegetation analysis, sub-merged and free-floating plants were scooped up from five randomly selected sites. Total bird counts were conducted for water birds and species richness, evenness and Shannon-Weaver species diversity indices were calculated. Results indicate that the organic load is very high in the wetland as evident from low levels of dissolved oxygen (2.26 ± 1.62 mg/l and high Biological and Chemical Oxygen Demands (15.20 ± 3.75 mg/l, 44.60 ± 12.07 mg/l. Nine species of free-floating and submerged plants were recorded; Hydrilla verticillata, Vallisneria spiralis, Azolla pinnata and Ceratophyllum demersum dominated both deep and shallow water areas. 52 species of waterbirds including four near-threatened species viz., Anhinga melanogaster, Mycteria leucocephala, Threskiornis melanocephalus and Aythya nyroca were recorded. OBS provides opportunities for conservation in a metropolitan area, thus, appropriate measures should be taken to maintain its ecological integrity.

  17. Genotypic and phenotypic diversity of Ralstonia pickettii and Ralstonia insidiosa isolates from clinical and environmental sources including High-purity Water. Diversity in Ralstonia pickettii

    Directory of Open Access Journals (Sweden)

    Adley Catherine C

    2011-08-01

    Full Text Available Abstract Background Ralstonia pickettii is a nosocomial infectious agent and a significant industrial contaminant. It has been found in many different environments including clinical situations, soil and industrial High Purity Water. This study compares the phenotypic and genotypic diversity of a selection of strains of Ralstonia collected from a variety of sources. Results Ralstonia isolates (fifty-nine from clinical, industrial and environmental origins were compared genotypically using i Species-specific-PCR, ii PCR and sequencing of the 16S-23S rRNA Interspatial region (ISR iii the fliC gene genes, iv RAPD and BOX-PCR and v phenotypically using biochemical testing. The species specific-PCR identified fifteen out of fifty-nine designated R. pickettii isolates as actually being the closely related species R. insidiosa. PCR-ribotyping of the 16S-23S rRNA ISR indicated few major differences between the isolates. Analysis of all isolates demonstrated different banding patterns for both the RAPD and BOX primers however these were found not to vary significantly. Conclusions R. pickettii species isolated from wide geographic and environmental sources appear to be reasonably homogenous based on genotypic and phenotypic characteristics. R. insidiosa can at present only be distinguished from R. pickettii using species specific PCR. R. pickettii and R. insidiosa isolates do not differ significantly phenotypically or genotypically based on environmental or geographical origin.

  18. Diverse coral communities in naturally acidified waters of a Western Pacific reef

    Science.gov (United States)

    Shamberger, Kathryn E. F.; Cohen, Anne L.; Golbuu, Yimnang; McCorkle, Daniel C.; Lentz, Steven J.; Barkley, Hannah C.

    2014-01-01

    Anthropogenic carbon dioxide emissions are acidifying the oceans, reducing the concentration of carbonate ions ([CO32-]) that calcifying organisms need to build and cement coral reefs. To date, studies of a handful of naturally acidified reef systems reveal depauperate communities, sometimes with reduced coral cover and calcification rates, consistent with results of laboratory-based studies. Here we report the existence of highly diverse, coral-dominated reef communities under chronically low pH and aragonite saturation state (Ωar). Biological and hydrographic processes change the chemistry of the seawater moving across the barrier reefs and into Palau's Rock Island bays, where levels of acidification approach those projected for the western tropical Pacific open ocean by 2100. Nevertheless, coral diversity, cover, and calcification rates are maintained across this natural acidification gradient. Identifying the combination of biological and environmental factors that enable these communities to persist could provide important insights into the future of coral reefs under anthropogenic acidification.

  19. Controls on the entrainment of juvenile Chinook Salmon (Oncorhynchus tshawytscha into large water diversions and estimates of population-level loss.

    Directory of Open Access Journals (Sweden)

    Steven C Zeug

    Full Text Available Diversion of freshwater can cause significant changes in hydrologic dynamics and this can have negative consequences for fish populations. Additionally, fishes can be directly entrained into diversion infrastructure (e.g. canals, reservoirs, pumps where they may become lost to the population. However, the effect of diversion losses on fish population dynamics remains unclear. We used 15 years of release and recovery data from coded-wire-tagged juvenile Chinook Salmon (Oncorhynchus tshawytscha to model the physical, hydrological and biological predictors of salvage at two large water diversions in the San Francisco Estuary. Additionally, entrainment rates were combined with estimates of mortality during migration to quantify the proportion of total mortality that could be attributed to diversions. Statistical modeling revealed a strong positive relationship between diversion rate and fish entrainment at both diversions and all release locations. Other significant relationships were specific to the rivers where the fish were released, and the specific diversion facility. Although significant relationships were identified in statistical models, entrainment loss and the mean contribution of entrainment to total migration mortality were low. The greatest entrainment mortality occurred for fish released along routes that passed closest to the diversions and certain runs of Chinook Salmon released in the Sacramento River suffered greater mortality but only at the highest diversion rates observed during the study. These results suggest losses at diversions should be put into a population context in order to best inform effective management of Chinook Salmon populations.

  20. Spatial variations in zooplankton diversity in waters contaminated with composite effluents

    Directory of Open Access Journals (Sweden)

    Asitava CHATTERJEE

    2007-08-01

    Full Text Available Zooplankton species are cosmopolitan in their clean freshwater habitat and are also found in industrial and municipal wastewaters. The present study records for the first time the aspects of zooplankton diversity in relation to physico-chemical environment of five selected sites of the East Calcutta wetlands, a Ramsar site of Kolkata city, India, heavily contaminated by industrial and municipal wastewaters. The study revealed the occurrence of 22 species of zooplankton, among these 3 species of Cladocera, 2 species of Copepoda, 15 species of Rotifera, and 2 species of Ostracoda were recorded. The copepod Mesocyclops leuckarti was found in all the five sites, rotifers Asplanchna brightwelli, Brachionus angularis, B. calyciflorus and Cladocera Ceriodaphnia cornuta were found in four sites; Moina micrura and Diaphanosoma sarsi were found at three sites. Site wise variation in dominance, diversity, evenness and richness were calculated. Site 1, a fish-pond that stabilized composite wastewater, showed the maximum species richness having 17 species, while Site 2, SWF wastewater carrying canal, showed only 4 species. The calculated Jack 1 values of Sites 1 to 5 were 21.78, 3.77, 18.63, 12.5 and 16.95 respectively. Shannon-Wiener species diversity index (H/ values were almost similar for all the three relatively less polluted sites viz, Site 1 (1.959, Site 4 (2.010, Site 5 (2.047. However, at highly polluted sites viz., 2 and 3, H/ value of 1.336 and 0.984 respectively, were calculated. Simpson’s Dominance index (Dsimp value was highest at Site 3 (0.618 indicating maximum dominance, whereas at Site 5 dominance was lowest (0.1680 and diversity was highest. We discuss the role of zooplankton in the amelioration of wastewater.

  1. Physico Chemical Characteristics of Lakhna Devi Temple Water Tank, Lakhna, Bakewar, Etawah, U.P. with reference to Cyanobacterial Diversity

    Directory of Open Access Journals (Sweden)

    Omesh Bajpai

    2013-08-01

    Full Text Available Fresh water bodies in populated plains of tropical countries face various disturbances in the form of pollutant and nutrient inflow, heavy metal and elemental precipitation (wet or dry and constant silt inflow (natural or anthropogenic. The physico-chemical characteristics are very much important for any water body. In lentic water bodies these characteristics shows very much variation because in summer they have less and in rains large amount of water. These adverse constrain effectively influence the algal assemblage and can be a good indicator of overall health of the water body. In the study different Physico-chemical characteristics and algal diversity were monthly observed for one year duration (Jun. 2008 to May 2009. Some of 31 species of Cyanobacteria recorded from the study site viz. Microcystis aerughinosa, M. flos-aquae, M. robusta, Chroococcus minor, C.minutes, Gloeocapsa magma, Aphanocapsa littoralis, Aphanothece microscopis, Coelosphaerium kuetzingianum, Merismopedia glauca, M. tenuissima, Arthrospira spriulinoides, Spirulina gigantean, S. major, Oscillatoria formosa, O. subuliformis, O. princeps, Phormidium ambiguum, P. fragile, P. lucidum, Lyngbya contorta, O. epiphytica, O.majuscule, Cylindrospermum minutissimum, Nostoc commune, N. punctiforme, Anabaena oscillarioides, A. oryzae, Calothrix gloeocola, Rivularia aquatic and Gloeotrichia pisum.

  2. Recovery of diverse microbes in high turbidity surface water samples using dead-end ultrafiltration

    Science.gov (United States)

    Mull, Bonnie; Hill, Vincent R.

    2015-01-01

    Dead-end ultrafiltration (DEUF) has been reported to be a simple, field-deployable technique for recovering bacteria, viruses, and parasites from large-volume water samples for water quality testing and waterborne disease investigations. While DEUF has been reported for application to water samples having relatively low turbidity, little information is available regarding recovery efficiencies for this technique when applied to sampling turbid water samples such as those commonly found in lakes and rivers. This study evaluated the effectiveness of a DEUF technique for recoveringMS2 bacteriophage, enterococci, Escherichia coli, Clostridium perfringens, and Cryptosporidium parvum oocysts in surface water samples having elevated turbidity. Average recovery efficiencies for each study microbe across all turbidity ranges were: MS2 (66%), C. parvum (49%), enterococci (85%), E. coli (81%), and C. perfringens (63%). The recovery efficiencies for MS2 and C. perfringens exhibited an inversely proportional relationship with turbidity, however no significant differences in recovery were observed for C. parvum, enterococci, or E. coli. Although ultrafilter clogging was observed, the DEUF method was able to process 100-L surface water samples at each turbidity level within 60 min. This study supports the use of the DEUF method for recovering a wide array of microbes in large-volume surface water samples having medium to high turbidity. PMID:23064261

  3. Diverse manganese(II)-oxidizing bacteria are prevalent in drinking water systems.

    Science.gov (United States)

    Marcus, Daniel N; Pinto, Ameet; Anantharaman, Karthik; Ruberg, Steven A; Kramer, Eva L; Raskin, Lutgarde; Dick, Gregory J

    2016-12-09

    Manganese (Mn) oxides are highly reactive minerals that influence the speciation, mobility, bioavailability and toxicity of a wide variety of organic and inorganic compounds. Although Mn(II)-oxidizing bacteria are known to catalyze the formation of Mn oxides, little is known about the organisms responsible for Mn oxidation in situ, especially in engineered environments. Mn(II)-oxidizing bacteria are important in drinking water systems, including in biofiltration and water distribution systems. Here, we used cultivation dependent and independent approaches to investigate Mn(II)-oxidizing bacteria in drinking water sources, a treatment plant and associated distribution system. We isolated 29 strains of Mn(II)-oxidizing bacteria and found that highly similar 16S rRNA gene sequences were present in all culture-independent datasets and dominant in the studied drinking water treatment plant. These results highlight a potentially important role for Mn(II)-oxidizing bacteria in drinking water systems, where biogenic Mn oxides may affect water quality in terms of aesthetic appearance, speciation of metals and oxidation of organic and inorganic compounds. Deciphering the ecology of these organisms and the factors that regulate their Mn(II)-oxidizing activity could yield important insights into how microbial communities influence the quality of drinking water.

  4. Occurrence of diverse alkane hydroxylase alkB genes in indigenous oil-degrading bacteria of Baltic Sea surface water.

    Science.gov (United States)

    Viggor, Signe; Jõesaar, Merike; Vedler, Eve; Kiiker, Riinu; Pärnpuu, Liis; Heinaru, Ain

    2015-12-30

    Formation of specific oil degrading bacterial communities in diesel fuel, crude oil, heptane and hexadecane supplemented microcosms of the Baltic Sea surface water samples was revealed. The 475 sequences from constructed alkane hydroxylase alkB gene clone libraries were grouped into 30 OPFs. The two largest groups were most similar to Pedobacter sp. (245 from 475) and Limnobacter sp. (112 from 475) alkB gene sequences. From 56 alkane-degrading bacterial strains 41 belonged to the Pseudomonas spp. and 8 to the Rhodococcus spp. having redundant alkB genes. Together 68 alkB gene sequences were identified. These genes grouped into 20 OPFs, half of them being specific only to the isolated strains. Altogether 543 diverse alkB genes were characterized in the brackish Baltic Sea water; some of them representing novel lineages having very low sequence identities with corresponding genes of the reference strains.

  5. Increasing Polychaete diversity as a consequence of increasing research effort in Greek waters: new records and exotic species

    Directory of Open Access Journals (Sweden)

    N. SIMBOURA

    2005-06-01

    Full Text Available The increasing diversity of the Greek Polychaete fauna over the last seven decades, as illustrated graphically, shows an increasing trend which is proportionately related to the research effort exerted. Ongoing research activities mainly in the depths of the N. Aegean Sea, as a result of which 13 new records have been added to the Greek Polychaete fauna, confirming the above statement. The new species records are presented along with their geographical distribution and habitat. According to the latest checklist of the Greek Polychaeta, 753 species of Polychaetes have been recorded in Greek waters. Finally, it should be noted that 6 Lessepsian migrants and 16 species have been recorded in the Mediterranean for the first time. Their distribution within Greece and worldwide is given and their presence in Greek waters is discussed.

  6. Increasing Polychaete diversity as a consequence of increasing research effort in Greek waters: new records and exotic species

    Directory of Open Access Journals (Sweden)

    N. SIMBOURA

    2012-12-01

    Full Text Available The increasing diversity of the Greek Polychaete fauna over the last seven decades, as illustrated graphically, shows an increasing trend which is proportionately related to the research effort exerted. Ongoing research activities mainly in the depths of the N. Aegean Sea, as a result of which 13 new records have been added to the Greek Polychaete fauna, confirming the above statement. The new species records are presented along with their geographical distribution and habitat. According to the latest checklist of the Greek Polychaeta, 753 species of Polychaetes have been recorded in Greek waters. Finally, it should be noted that 6 Lessepsian migrants and 16 species have been recorded in the Mediterranean for the first time. Their distribution within Greece and worldwide is given and their presence in Greek waters is discussed.

  7. Higher Water Temperature and Incubation under Aerobic and Microaerobic Conditions Increase the Recovery and Diversity of Arcobacter spp. from Shellfish

    Science.gov (United States)

    Levican, Arturo; Collado, Luis; Yustes, Clara; Aguilar, Carme

    2014-01-01

    Some Arcobacter species are considered emerging food-borne and waterborne pathogens, and shellfish have been suggested as one of their reservoirs. However, only a few studies have investigated the presence of Arcobacter in this kind of food. This study assesses the prevalence and diversity of Arcobacter spp. in shellfish by multiplex PCR (m-PCR) and culturing methods (under different atmospheric conditions) and evaluates the possible influence of environmental parameters (temperature, salinity, and harvesting bay). Arcobacter was detected by m-PCR and/or culturing in 61 (29.9%) of 204 shellfish samples. Of the positive samples by culturing, 41.1% were obtained under only aerobic incubation conditions, while 23.2% were obtained under only microaerobic conditions. Of 476 investigated isolates, 118 belonged to different enterobacterial repetitive intergenic consensus (ERIC)-PCR genotypes (strains) and to 11 different species. This study shows the highest diversity of Arcobacter species ever observed in samples from any origin. The most prevalent species was Arcobacter butzleri (60.2%), followed by Arcobacter molluscorum (21.2%). The prevalence of Arcobacter was significantly higher during the summer than in other seasons, being associated with an increase in water temperature. Results confirm that shellfish are a reservoir for a remarkable diversity of Arcobacter spp. PMID:24185851

  8. Higher water temperature and incubation under aerobic and microaerobic conditions increase the recovery and diversity of Arcobacter spp. from shellfish.

    Science.gov (United States)

    Levican, Arturo; Collado, Luis; Yustes, Clara; Aguilar, Carme; Figueras, Maria José

    2014-01-01

    Some Arcobacter species are considered emerging food-borne and waterborne pathogens, and shellfish have been suggested as one of their reservoirs. However, only a few studies have investigated the presence of Arcobacter in this kind of food. This study assesses the prevalence and diversity of Arcobacter spp. in shellfish by multiplex PCR (m-PCR) and culturing methods (under different atmospheric conditions) and evaluates the possible influence of environmental parameters (temperature, salinity, and harvesting bay). Arcobacter was detected by m-PCR and/or culturing in 61 (29.9%) of 204 shellfish samples. Of the positive samples by culturing, 41.1% were obtained under only aerobic incubation conditions, while 23.2% were obtained under only microaerobic conditions. Of 476 investigated isolates, 118 belonged to different enterobacterial repetitive intergenic consensus (ERIC)-PCR genotypes (strains) and to 11 different species. This study shows the highest diversity of Arcobacter species ever observed in samples from any origin. The most prevalent species was Arcobacter butzleri (60.2%), followed by Arcobacter molluscorum (21.2%). The prevalence of Arcobacter was significantly higher during the summer than in other seasons, being associated with an increase in water temperature. Results confirm that shellfish are a reservoir for a remarkable diversity of Arcobacter spp.

  9. Using Amplicon Sequencing To Characterize and Monitor Bacterial Diversity in Drinking Water Distribution Systems

    Science.gov (United States)

    Shaw, Jennifer L. A.; Weyrich, Laura S.; Sawade, Emma; Drikas, Mary; Cooper, Alan J.

    2015-01-01

    Drinking water assessments use a variety of microbial, physical, and chemical indicators to evaluate water treatment efficiency and product water quality. However, these indicators do not allow the complex biological communities, which can adversely impact the performance of drinking water distribution systems (DWDSs), to be characterized. Entire bacterial communities can be studied quickly and inexpensively using targeted metagenomic amplicon sequencing. Here, amplicon sequencing of the 16S rRNA gene region was performed alongside traditional water quality measures to assess the health, quality, and efficiency of two distinct, full-scale DWDSs: (i) a linear DWDS supplied with unfiltered water subjected to basic disinfection before distribution and (ii) a complex, branching DWDS treated by a four-stage water treatment plant (WTP) prior to disinfection and distribution. In both DWDSs bacterial communities differed significantly after disinfection, demonstrating the effectiveness of both treatment regimes. However, bacterial repopulation occurred further along in the DWDSs, and some end-user samples were more similar to the source water than to the postdisinfection water. Three sample locations appeared to be nitrified, displaying elevated nitrate levels and decreased ammonia levels, and nitrifying bacterial species, such as Nitrospira, were detected. Burkholderiales were abundant in samples containing large amounts of monochloramine, indicating resistance to disinfection. Genera known to contain pathogenic and fecal-associated species were also identified in several locations. From this study, we conclude that metagenomic amplicon sequencing is an informative method to support current compliance-based methods and can be used to reveal bacterial community interactions with the chemical and physical properties of DWDSs. PMID:26162884

  10. Using Amplicon Sequencing To Characterize and Monitor Bacterial Diversity in Drinking Water Distribution Systems.

    Science.gov (United States)

    Shaw, Jennifer L A; Monis, Paul; Weyrich, Laura S; Sawade, Emma; Drikas, Mary; Cooper, Alan J

    2015-09-01

    Drinking water assessments use a variety of microbial, physical, and chemical indicators to evaluate water treatment efficiency and product water quality. However, these indicators do not allow the complex biological communities, which can adversely impact the performance of drinking water distribution systems (DWDSs), to be characterized. Entire bacterial communities can be studied quickly and inexpensively using targeted metagenomic amplicon sequencing. Here, amplicon sequencing of the 16S rRNA gene region was performed alongside traditional water quality measures to assess the health, quality, and efficiency of two distinct, full-scale DWDSs: (i) a linear DWDS supplied with unfiltered water subjected to basic disinfection before distribution and (ii) a complex, branching DWDS treated by a four-stage water treatment plant (WTP) prior to disinfection and distribution. In both DWDSs bacterial communities differed significantly after disinfection, demonstrating the effectiveness of both treatment regimes. However, bacterial repopulation occurred further along in the DWDSs, and some end-user samples were more similar to the source water than to the postdisinfection water. Three sample locations appeared to be nitrified, displaying elevated nitrate levels and decreased ammonia levels, and nitrifying bacterial species, such as Nitrospira, were detected. Burkholderiales were abundant in samples containing large amounts of monochloramine, indicating resistance to disinfection. Genera known to contain pathogenic and fecal-associated species were also identified in several locations. From this study, we conclude that metagenomic amplicon sequencing is an informative method to support current compliance-based methods and can be used to reveal bacterial community interactions with the chemical and physical properties of DWDSs. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  11. Hydrology and water quality of Shell Lake, Washburn County, Wisconsin, with special emphasis on the effects of diversion and changes in water level on the water quality of a shallow terminal lake

    Science.gov (United States)

    Juckem, Paul F.; Robertson, Dale M.

    2013-01-01

    Shell Lake is a relatively shallow terminal lake (tributaries but no outlets) in northwestern Wisconsin that has experienced approximately 10 feet (ft) of water-level fluctuation over more than 70 years of record and extensive flooding of nearshore areas starting in the early 2000s. The City of Shell Lake (City) received a permit from the Wisconsin Department of Natural Resources in 2002 to divert water from the lake to a nearby river in order to lower water levels and reduce flooding. Previous studies suggested that water-level fluctuations were driven by long-term cycles in precipitation, evaporation, and runoff, although questions about the lake’s connection with the groundwater system remained. The permit required that the City evaluate assumptions about lake/groundwater interactions made in previous studies and evaluate the effects of the water diversion on water levels in Shell Lake and other nearby lakes. Therefore, a cooperative study between the City and U.S. Geological Survey (USGS) was initiated to improve the understanding of the hydrogeology of the area and evaluate potential effects of the diversion on water levels in Shell Lake, the surrounding groundwater system, and nearby lakes. Concerns over deteriorating water quality in the lake, possibly associated with changes in water level, prompted an additional cooperative project between the City and the USGS to evaluate efeffects of changes in nutrient loading associated with changes in water levels on the water quality of Shell Lake. Numerical models were used to evaluate how the hydrology and water quality responded to diversion of water from the lake and historical changes in the watershed. The groundwater-flow model MODFLOW was used to simulate groundwater movement in the area around Shell Lake, including groundwater/surface-water interactions. Simulated results from the MODFLOW model indicate that groundwater flows generally northward in the area around Shell Lake, with flow locally converging

  12. Irrigation Wells from the Utah Division of Water Rights Point of Diversion Database

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data are derived from a point shapefile created nightly from data in the Utah Division of Water Rights Database. The source data were acquired on October 26,...

  13. Ecological Effects of the South-to-North Water Diversion Project on the Hanjiang River

    Institute of Scientific and Technical Information of China (English)

    DU Yun; WANG Xuelei; CAI Shuming

    2006-01-01

    @@ The middle and lower reaches of the Hanjiang River are the center of local economic development in the region. For a long time the mother nature's mighty force and mankind's infringement have led to a series of ecological problems,such as flooding and water-logging calamities, droughts, soil erosion &water loss, downgrade of environmental quality, shrinkage of wetland resources, posing threats to the valley's sustainable development.

  14. Next-Generation Sequencing Assessment of Eukaryotic Diversity in Oil Sands Tailings Ponds Sediments and Surface Water.

    Science.gov (United States)

    Aguilar, Maria; Richardson, Elisabeth; Tan, BoonFei; Walker, Giselle; Dunfield, Peter F; Bass, David; Nesbø, Camilla; Foght, Julia; Dacks, Joel B

    2016-11-01

    Tailings ponds in the Athabasca oil sands (Canada) contain fluid wastes, generated by the extraction of bitumen from oil sands ores. Although the autochthonous prokaryotic communities have been relatively well characterized, almost nothing is known about microbial eukaryotes living in the anoxic soft sediments of tailings ponds or in the thin oxic layer of water that covers them. We carried out the first next-generation sequencing study of microbial eukaryotic diversity in oil sands tailings ponds. In metagenomes prepared from tailings sediment and surface water, we detected very low numbers of sequences encoding eukaryotic small subunit ribosomal RNA representing seven major taxonomic groups of protists. We also produced and analysed three amplicon-based 18S rRNA libraries prepared from sediment samples. These revealed a more diverse set of taxa, 169 different OTUs encompassing up to eleven higher order groups of eukaryotes, according to detailed classification using homology searching and phylogenetic methods. The 10 most abundant OTUs accounted for > 90% of the total of reads, vs. large numbers of rare OTUs (tailings ponds harbour complex communities of microbial eukaryotes indicating that these organisms should be taken into account when studying the microbiology of the oil sands. © 2016 The Author(s) Journal of Eukaryotic Microbiology © 2016 International Society of Protistologists.

  15. Effect of diesel leakage in circulating cooling water system on preponderant bacteria diversity and bactericidal effect of biocides.

    Science.gov (United States)

    Zhong, Huiyun; Liu, Fang; Lu, Jinjin; Yang, Wei; Zhao, Chaocheng

    2015-01-01

    Petroleum products leakage results in adverse effect on the normal operation of a circulating cooling water system. However, relatively little research has been done to explore the effect of petroleum products leakage on circulating cooling water quality and biofilm preponderant bacteria diversity. Also, normal biocides application modes cannot fulfil the need for biofilm control. In this study, diesel oil was used as the experimental subject representing leaking petroleum products; the effect of diesel addition on biofilm preponderant bacteria diversity and the bactericidal effect of chlorine dioxide and tetradecyl dimethyl benzyl ammonium chloride (1427) was investigated. Bacterial community structures were examined by PCR-denaturing gradient gel electrophoresis and PCR cloning of 16S rDNA genes. Except for 100 mg/L diesel, increasing diesel concentration enhanced the biofilm detachment ratio compared with the control test. The microstructure of biofilm samples with 0, 300 and 900 mg/L diesel addition was observed. The species of preponderant bacteria in the biofilm sample with 300 mg/L diesel addition were more and the bacterial distribution was more uniform than those in the biofilm sample with 900 mg/L diesel addition. With ClO2 and 1427 addition, chemical oxygen demand increased, lipid phosphorus and bacterial count first decreased and then remained stable, and the bactericidal ratio first increased and then remained stable. Diesel addition variation has more obvious effect on ClO2 than 1427.

  16. Diversity and antibiotic resistance patterns of Sphingomonadaceae isolates from drinking water.

    Science.gov (United States)

    Vaz-Moreira, Ivone; Nunes, Olga C; Manaia, Célia M

    2011-08-15

    Sphingomonadaceae (n = 86) were isolated from a drinking water treatment plant (n = 6), tap water (n = 55), cup fillers for dental chairs (n = 21), and a water demineralization filter (n = 4). The bacterial isolates were identified based on analysis of the 16S rRNA gene sequence, and intraspecies variation was assessed on the basis of atpD gene sequence analysis. The isolates were identified as members of the genera Sphingomonas (n = 27), Sphingobium (n = 28), Novosphingobium (n = 12), Sphingopyxis (n = 7), and Blastomonas (n = 12). The patterns of susceptibility to five classes of antibiotics were analyzed and compared for the different sites of isolation and taxonomic groups. Colistin resistance was observed to be intrinsic (92%). The highest antibiotic resistance prevalence values were observed in members of the genera Sphingomonas and Sphingobium and for beta-lactams, ciprofloxacin, and cotrimoxazole. In tap water and in water from dental chairs, antibiotic resistance was more prevalent than in the other samples, mainly due to the predominance of isolates of the genera Sphingomonas and Sphingobium. These two genera presented distinct patterns of association with antibiotic resistance, suggesting different paths of resistance development. Antibiotic resistance patterns were often related to the species rather than to the site or strain, suggesting the importance of vertical resistance transmission in these bacteria. This is the first study demonstrating that members of the family Sphingomonadaceae are potential reservoirs of antibiotic resistance in drinking water.

  17. Genetic diversity of free-living Symbiodinium in surface water and sediment of Hawai`i and Florida

    Science.gov (United States)

    Takabayashi, M.; Adams, L. M.; Pochon, X.; Gates, R. D.

    2012-03-01

    Marine dinoflagellates in the genus Symbiodinium are primarily known for their symbiotic associations with invertebrates and protists, although they are also found free-living in nanoplankton and microphytobenthic communities. Free-living Symbiodinium are necessary for hosts that must acquire their symbionts anew each generation and for the possible reestablishment of endosymbiosis in bleached adults. The diversity and ecology of free-living Symbiodinium are not well studied by comparison with their endosymbiotic counterparts, and as a result, our understanding of the linkages between free-living and endosymbiotic Symbiodinium is poor. Here, we begin to address this knowledge gap by describing the genetic diversity of Symbiodinium in the surface water and reef sediments of Hawai`i and Florida using Symbiodinium-specific primers for the hypervariable region of the chloroplast 23S domain V (cp23S-HVR). In total, 29 Symbiodinium sequence types were detected, 16 of which were novel. The majority of Symbiodinium sequence types in free-living environments belonged to clades A and B, but smaller numbers of sequence types belonging to clades C, D, and G were also detected. The majority of sequences recovered from Hawai`i belonged to clades A and C and those from Florida to clade B. Such distribution patterns are consistent with the endosymbiotic diversity previously reported for these two regions. The ancestral sequence types in each clade were typically recovered from surface water and sediments both in Hawai`i and Florida and have been previously reported as endosymbionts of a range of invertebrates, suggesting that these types have the capacity to exploit a range of very different habitats. More derived sequence types in clades A, B, C, and G were not recovered here, suggesting they are potentially restricted to endosymbiotic environments.

  18. Diversity and phylogenetic analyses of bacteria from a shallow-water hydrothermal vent in Milos island (Greece).

    Science.gov (United States)

    Giovannelli, Donato; d'Errico, Giuseppe; Manini, Elena; Yakimov, Michail; Vetriani, Costantino

    2013-01-01

    Studies of shallow-water hydrothermal vents have been lagging behind their deep-sea counterparts. Hence, the importance of these systems and their contribution to the local and regional diversity and biogeochemistry is unclear. This study analyzes the bacterial community along a transect at the shallow-water hydrothermal vent system of Milos island, Greece. The abundance and biomass of the prokaryotic community is comparable to areas not affected by hydrothermal activity and was, on average, 1.34 × 10(8) cells g(-1). The abundance, biomass and diversity of the prokaryotic community increased with the distance from the center of the vent and appeared to be controlled by the temperature gradient rather than the trophic conditions. The retrieved 16S rRNA gene fragments matched sequences from a variety of geothermal environments, although the average similarity was low (94%), revealing previously undiscovered taxa. Epsilonproteobacteria constituted the majority of the population along the transect, with an average contribution to the total diversity of 60%. The larger cluster of 16S rRNA gene sequences was related to chemolithoautotrophic Sulfurovum spp., an Epsilonproteobacterium so far detected only at deep-sea hydrothermal vents. The presence of previously unknown lineages of Epsilonproteobacteria could be related to the abundance of organic matter in these systems, which may support alternative metabolic strategies to chemolithoautotrophy. The relative contribution of Gammaproteobacteria to the Milos microbial community increased along the transect as the distance from the center of the vent increased. Further attempts to isolate key species from these ecosystems will be critical to shed light on their evolution and ecology.

  19. Forecasting and prevention of water inrush during the excavation process of a diversion tunnel at the Jinping II Hydropower Station, China.

    Science.gov (United States)

    Hou, Tian-Xing; Yang, Xing-Guo; Xing, Hui-Ge; Huang, Kang-Xin; Zhou, Jia-Wen

    2016-01-01

    Estimating groundwater inflow into a tunnel before and during the excavation process is an important task to ensure the safety and schedule during the underground construction process. Here we report a case of the forecasting and prevention of water inrush at the Jinping II Hydropower Station diversion tunnel groups during the excavation process. The diversion tunnel groups are located in mountains and valleys, and with high water pressure head. Three forecasting methods are used to predict the total water inflow of the #2 diversion tunnel. Furthermore, based on the accurate estimation of the water inrush around the tunnel working area, a theoretical method is presented to forecast the water inflow at the working area during the excavation process. The simulated results show that the total water flow is 1586.9, 1309.4 and 2070.2 m(3)/h using the Qshima method, Kostyakov method and Ochiai method, respectively. The Qshima method is the best one because it most closely matches the monitoring result. According to the huge water inflow into the #2 diversion tunnel, reasonable drainage measures are arranged to prevent the potential disaster of water inrush. The groundwater pressure head can be determined using the water flow velocity from the advancing holes; then, the groundwater pressure head can be used to predict the possible water inflow. The simulated results show that the groundwater pressure head and water inflow re stable and relatively small around the region of the intact rock mass, but there is a sudden change around the fault region with a large water inflow and groundwater pressure head. Different countermeasures are adopted to prevent water inrush disasters during the tunnel excavation process. Reasonable forecasting the characteristic parameters of water inrush is very useful for the formation of prevention and mitigation schemes during the tunnel excavation process.

  20. A modeling study of the impacts of Mississippi River diversion and sea-level rise on water quality of a deltaic estuary

    Science.gov (United States)

    Wang, Hongqing; Chen, Qin; Hu, Kelin; LaPeyre, Megan K.

    2017-01-01

    Freshwater and sediment management in estuaries affects water quality, particularly in deltaic estuaries. Furthermore, climate change-induced sea-level rise (SLR) and land subsidence also affect estuarine water quality by changing salinity, circulation, stratification, sedimentation, erosion, residence time, and other physical and ecological processes. However, little is known about how the magnitudes and spatial and temporal patterns in estuarine water quality variables will change in response to freshwater and sediment management in the context of future SLR. In this study, we applied the Delft3D model that couples hydrodynamics and water quality processes to examine the spatial and temporal variations of salinity, total suspended solids, and chlorophyll-α concentration in response to small (142 m3 s−1) and large (7080 m3 s−1) Mississippi River (MR) diversions under low (0.38 m) and high (1.44 m) relative SLR (RSLR = eustatic SLR + subsidence) scenarios in the Breton Sound Estuary, Louisiana, USA. The hydrodynamics and water quality model were calibrated and validated via field observations at multiple stations across the estuary. Model results indicate that the large MR diversion would significantly affect the magnitude and spatial and temporal patterns of the studied water quality variables across the entire estuary, whereas the small diversion tends to influence water quality only in small areas near the diversion. RSLR would also play a significant role on the spatial heterogeneity in estuary water quality by acting as an opposite force to river diversions; however, RSLR plays a greater role than the small-scale diversion on the magnitude and spatial pattern of the water quality parameters in this deltaic estuary.

  1. Evidence and characteristics of a diverse and metabolically active microbial community in deep subsurface clay borehole water.

    Science.gov (United States)

    Wouters, Katinka; Moors, Hugo; Boven, Patrick; Leys, Natalie

    2013-12-01

    The Boom Clay in Belgium is investigated in the context of geological nuclear waste disposal, making use of the High Activity Disposal Experimental Site (HADES) underground research facility. This facility, located in the Boom Clay at a depth of 225 m below the surface, offers a unique access to a microbial community in an environment, of which all geological and geochemical characteristics are being thoroughly studied. This study presents the first elaborate description of a microbial community in water samples retrieved from a Boom Clay piezometer (borehole water). Using an integrated approach of microscopy, metagenomics, activity screening and cultivation, the presence and activity of this community are disclosed. Despite the presumed low-energy environment, microscopy and molecular analyses show a large bacterial diversity and richness, tending to correlate positively with the organic matter content of the environment. Among 10 borehole water samples, a core bacterial community comprising seven bacterial phyla is defined, including both aerobic and anaerobic genera with a range of metabolic preferences. In addition, a corresponding large fraction of this community is found cultivable and active. In conclusion, this study shows the possibility of a microbial community of relative complexity to persist in subsurface Boom Clay borehole water. © 2013 Federation of European Microbiological Societies. Published by John Wiley & Sons Ltd. All rights reserved.

  2. Evolved-Lithology Clasts in Lunar Breccias: Relating Petrogenetic Diversity to Measured Water Content

    Science.gov (United States)

    Christoffersen, R.; Simon, J. J.; Ross, D. K.

    2017-01-01

    Studies of the inventory and distribution of water in lunar rocks have recently begun to focus on alkali suite samples as possible water repositories, particularly the most highly evolved granitoid lithologies. Although H analyses of feldspars in these rocks have so far pointed to 'low' (less than 20 ppm) H2O contents, there is sufficient variability in the dataset (e.g., 2-20 ppm) to warrant consideration of the petrogenetic factors that may have caused some granitoid-to-intermediate rocks to be dryer or wetter than others. Given that all examples of these rocks occur as clasts in complex impact breccias, the role of impact and other factors in altering water contents established by primary igneous processes becomes a major factor. We are supporting our ongoing SIMS studies of water in evolved lunar lithologies with systematic SEM and EPMA observations. Here we report a synthesis of the observations as part of developing discriminating factors for reconstructing the thermal, crystallization and shock history of these samples as compared with their water contents.

  3. Antimicrobial resistance, virulence factors and genetic diversity of Escherichia coli isolates from household water supply in Dhaka, Bangladesh.

    Directory of Open Access Journals (Sweden)

    Prabhat Kumar Talukdar

    Full Text Available BACKGROUND: Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected from different locations of the city were characterized for their antibiotic resistance, pathogenic properties and genetic diversity. METHODOLOGY/PRINCIPAL FINDINGS: A total of 233 E. coli isolates obtained from 175 tap water samples were analysed for susceptibility to 16 different antibiotics and for the presence of genes associated with virulence and antibiotic resistance. Nearly 36% (n = 84 of the isolates were multi-drug(≥ 3 classes of antibiotics resistant (MDR and 26% (n = 22 of these were positive for extended spectrum β-lactamase (ESBL. Of the 22 ESBL-producers, 20 were positive for bla CTX-M-15, 7 for bla OXA-1-group (all had bla OXA-47 and 2 for bla CMY-2. Quinolone resistance genes, qnrS and qnrB were detected in 6 and 2 isolates, respectively. Around 7% (n = 16 of the isolates carried virulence gene(s characteristic of pathogenic E. coli; 11 of these contained lt and/or st and thus belonged to enterotoxigenic E. coli and 5 contained bfp and eae and thus belonged to enteropathogenic E. coli. All MDR isolates carried multiple plasmids (2 to 8 of varying sizes ranging from 1.2 to >120 MDa. Ampicillin and ceftriaxone resistance were co-transferred in conjugative plasmids of 70 to 100 MDa in size, while ampicillin, trimethoprim-sulfamethoxazole and tetracycline resistance were co-transferred in conjugative plasmids of 50 to 90 MDa. Pulsed-field gel electrophoresis analysis revealed diverse genetic fingerprints of pathogenic isolates. SIGNIFICANCE: Multi-drug resistant E. coli are wide spread in public water supply in Dhaka city, Bangladesh. Transmission of resistant bacteria and plasmids through supply water pose serious threats to public health in

  4. Diversity of Phytoplankton of the Water Reservoir of Betania-Huila and its Importance as Bioindicators

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    PAULA MARTINEZ SILVA

    2016-08-01

    Full Text Available The Betania reservoir of water is one of the strategic ecosystems of the Huila department, being of vital importance not only for the generation of electricity but for the production of fish which is the main activity for the last thirty years. Nevertheless, activities such as pisiculture, the dumping of wastewater generated by agricultural activities, have diminished the quality of the water and accelerated the eutrophication process. In this research, phytoplankton samples were taken along one year with the objective to stablish through the use of bioindicators, such as microalgae, the actual state of this water body as well as the spatial – temporal variation of species and genres of algae amongst stations and samplings.

  5. Comammox Nitrospira are key nitrifiers in diverse groundwater-fed drinking water filters

    DEFF Research Database (Denmark)

    Fowler, Jane; Palomo, Alejandro; Smets, Barth F.

    Nitrification is a dominant process in groundwater-fed rapid sand filters (RSFs) used for drinking water purification. Near complete removal of ammonium and nitrite is required in the EU and Denmark due to strict regulatory limits that enable high water stability in the distribution system. RSFs...... to comprise both nitrite oxidizers as well as complete nitrifying (comammox) Nitrospira spp. (Palomo et al. 2016). We developed a new qPCR assay for the quantification of the comammox Nitrospira amoA gene which amplifies both clades A and B and applied this assay to the study of 12 drinking water treatment...... Nitrospira communities. Further examination of groundwater-fed RSFs with higher variability in microbial communities and physicochemical parameters may provide further information on the ecology of comammox Nitrospira and explain their success in the groundwater-fed filters examined in this study. Together...

  6. Genetic diversity in Trypanosoma theileri from Sri Lankan cattle and water buffaloes.

    Science.gov (United States)

    Yokoyama, Naoaki; Sivakumar, Thillaiampalam; Fukushi, Shintaro; Tattiyapong, Muncharee; Tuvshintulga, Bumduuren; Kothalawala, Hemal; Silva, Seekkuge Susil Priyantha; Igarashi, Ikuo; Inoue, Noboru

    2015-01-30

    Trypanosoma theileri is a hemoprotozoan parasite that infects various ruminant species. We investigated the epidemiology of this parasite among cattle and water buffalo populations bred in Sri Lanka, using a diagnostic PCR assay based on the cathepsin L-like protein (CATL) gene. Blood DNA samples sourced from cattle (n=316) and water buffaloes (n=320) bred in different geographical areas of Sri Lanka were PCR screened for T. theileri. Parasite DNA was detected in cattle and water buffaloes alike in all the sampling locations. The overall T. theileri-positive rate was higher in water buffaloes (15.9%) than in cattle (7.6%). Subsequently, PCR amplicons were sequenced and the partial CATL sequences were phylogenetically analyzed. The identity values for the CATL gene were 89.6-99.7% among the cattle-derived sequences, compared with values of 90.7-100% for the buffalo-derived sequences. However, the cattle-derived sequences shared 88.2-100% identity values with those from buffaloes. In the phylogenetic tree, the Sri Lankan CATL gene sequences fell into two major clades (TthI and TthII), both of which contain CATL sequences from several other countries. Although most of the CATL sequences from Sri Lankan cattle and buffaloes clustered independently, two buffalo-derived sequences were observed to be closely related to those of the Sri Lankan cattle. Furthermore, a Sri Lankan buffalo sequence clustered with CATL gene sequences from Brazilian buffalo and Thai cattle. In addition to reporting the first PCR-based survey of T. theileri among Sri Lankan-bred cattle and water buffaloes, the present study found that some of the CATL gene fragments sourced from water buffaloes shared similarity with those determined from cattle in this country.

  7. Turbidity as an Indicator of Water Quality in Diverse Watersheds of the Upper Pecos River Basin

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    Gregory M. Huey

    2010-06-01

    Full Text Available Microbial concentrations, total suspended solids (TSS and turbidity vary with stream hydrology and land use. Turbidity, TSS, and microbial concentrations, loads and yields from four watersheds were assessed: an unburned montane forest, a catastrophically burned montane forest, urban land use and rangeland prairie. Concentrations and loads for most water quality variables were greatest during storm events. Turbidity was an effective indicator of TSS, E. coli and Enterococci spp. The greatest threat to public health from microbial contamination occurs during storm runoff events. Efforts to manage surface runoff and erosion would likely improve water quality of the upper Pecos River basin in New Mexico, USA.

  8. Investigating Groundwater/Surface Water Interaction at the Diversion Dam Site: Report Documentary 2007-2008

    Science.gov (United States)

    2011-05-01

    and setup issues concerning the loggers and the ERDC/CHL CR-11-1 8 Figure 4. Solinst Gold Model 3001 pressure transducer. learning curve that...applicable. • Enviro 2” locking well cap w/key, and a ring from a key chain to suspend the LGR • Water level beeper (submersible type if measuring DTR

  9. Physicochemical Analysis and Microbial Diversity of Yamuna Water and Industrial Effluents

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    Poonam Gupta

    2014-06-01

    Full Text Available Pollution has arisen as a serious environmental concern to the present world after industrialization of human societies. It has severely affected our air, soil and water sources. Looking to its global, national, regional and local dimensions, it is now imperative to check it at each and every level. In the present study, 8 samples (3 Yamuna water samples, 3 tannery effluent samples and 2 textile effluent samples, were collected from different sites of Yamuna and exit points of textile and tannery Industries. Water and effluent samples were analysed for various physicochemical parameters (pH, TDS, hardness, chloride and BOD using conventional methods. Afterwards these samples were utilized for isolation of the native bacterial species. All the samples were showing higher than the standard values for TDS (500mg/l, hardness (80-100 mg/l, chloride (250mg/l and BOD (30mg/l. It was observed that the tannery effluents were showing maximum TDS values(1190-1240mg/l, followed by textile effluents (1190 and 1210mg/l and Yamuna water (530-1180mg/l.Similarly, in case of chloride content, highest concentration range(828.8-1598mg/lwas shown by tannery effluents. pH value was nearly neutral for Yamuna water, slightly acidic in case of textile effluents and more acidic for tannery samples. Highest range of hardness values were observed for the tannery effluents (860-880mg/l followed by textile effluents (760 and 860mg/l. The BOD values were nearly similar for all the samples with maximum values being observed for tannery effluents (42-48 mg/l. Thus it can be inferred that all the samples were highly polluted and need to be treated by suitable methods. There were 11 cultures purified, that could be employed in bioremediation purposes.

  10. Correlation of Oil-Water and Air-Water Contact Angles of Diverse Silanized Surfaces and Relationship to Fluid Interfacial Tensions

    Energy Technology Data Exchange (ETDEWEB)

    Grate, Jay W.; Dehoff, Karl J.; Warner, Marvin G.; Pittman, Jonathan W.; Wietsma, Thomas W.; Zhang, Changyong; Oostrom, Martinus

    2012-02-24

    The use of air-water, {Theta}{sub wa}, or air-liquid contact angles is customary in surface science, while oil-water contact angles {Theta}{sub ow}, are of paramount importance in subsurface multiphase flow phenomena including petroleum reocovery, nonaqueous phase liquid fate and transport, and geological carbon sequestration. In this paper we determine both the air-water and oil-water contact angles of silica surfaces modified with a diverse selection of silanes, using hexadecane as the oil. The silanes included alkylsilanes, alkylarylsilanes, and silanes with alkyl or aryl groups that are functionalized with heteroatoms such as N, O, and S. These silanes yielded surfaces with wettabilities from water-wet to oil wet, including specific silanized surfaces functionalized with heteroatoms that yield intermediate wet surfaces. The oil-water contact angles for clean and silanized surfaces, excluding one partially fluorinated surface, correlate linearly with air-water contact angles with a slope of 1.41 (R = 0.981, n = 13). These data were used to examine a previously untested theoretical treatment relating air-water and oil-water contact angles in terms of fluid interfacial energies. Plotting the cosines of these contact angles against one another, we obtain a linear relationship in excellent agreement with the theoretical treatment; the data fit cos {Theta}{sub ow} = 0.667 cos {Theta}{sub ow} + 0.384 (R = 0.981, n = 13), intercepting cos {Theta}{sub ow} = -1 at -0.284. The theoretical slope, based on the fluid interfacial tensions {Theta}{sub wa}, {Theta}{sub ow}, and {Theta}{sub oa}, is 0.67. We also demonstrate how silanes can be used to alter the wettability of the interior of a pore network micromodel device constructed in silicon/silica with a glass cover plate. Such micromodels are used to study multiphase flow phenomena. The contact angle of the resulting interior was determined in situ. An intermediate wet micromodel gave a contact angle in excellent agreement

  11. Phytoplankton diversity and their succession in water bodies of the Lednice park during 2002 season

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    Zohreh Ramezanpoor

    2004-01-01

    Full Text Available Phytoplankton communities of three water bodies in the Lednice park were studied from 22nd April till 1st October 2002. These water bodies are the Zámecký pond, Růžový pond and the Dyje River, which is water source of both ponds.Phytoplankton samples were taken every two weeks between 8 - 9 am. Collected phytoplankton samples were preserved with 4% formalin solution and Lugol solution (JJK and transported to the laboratory. They were determined and counted using inverted microscope. Water temperature, pH and dissolved oxygen were measured in the field using digital portable instruments. Total of 317 phytoplankton species were determined in this study.Heavy algal bloom was observed in the Zámecký pond in mid-summer coinciding with increase in water temperature. Fish diseases and partial mortality occurred during the period of algal bloom and unpleasant smell was dominant feature. A light algal bloom was also observed in the Růžový pond and the Dyje River nearly by the end of summer.The main algae species responsible for blue-green algae bloom were Anabaena flos-aquae, Microcystis aeruginosa, M. ichtyoblabe, M. flos-aquae and M. wesenbergii. Dissolved oxygen values varied between 3.4 - 19.5 mg l-1, pH ranged from 7.6 - 9.7. Secchi depth varied from 0- 65 cm in the Zámecký pond, 15-45 cm in the Růžový pond and 35-65 cm in the Dyje River. Concentration of total phosphate, nitrate and chlorophyll-a in the Dyje River before drainage into the Zámecký and Růžový pond verified heavy nutrient load (Total-P = 0.3, NO3- = 12 mg.l-1 of the river. Although the Dyje River is main water source for both ponds, presence of relatively different phytoplankton communities in these two ponds suggest that probably different nutrient sources might be responsible for differences in phytoplankton communities and eutrophication patterns in the Zámecký pond as compared to the Růžový pond.

  12. Diazotroph diversity in the sea ice, melt ponds and surface waters of the Eurasian Basin of the Central Arctic Ocean

    Directory of Open Access Journals (Sweden)

    Mar Fernández-Méndez

    2016-11-01

    Full Text Available The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which encodes the iron protein of the nitrogenase enzyme. We amplified 529 nifH sequences from 26 samples of Arctic melt ponds, sea ice and surface waters. These sequences resolved into 43 clusters at 92% amino acid sequence identity, most of which were non-cyanobacterial phylotypes from sea ice and water samples. One cyanobacterial phylotype related to Nodularia sp. was retrieved from sea ice, suggesting that this important functional group is rare in the Central Arctic Ocean. The diazotrophic community in sea-ice environments appear distinct from other cold-adapted diazotrophic communities, such as those present in the coastal Canadian Arctic, the Arctic tundra and glacial Antarctic lakes. Molecular fingerprinting of nifH and the intergenic spacer region of the rRNA operon revealed differences between the communities from river-influenced Laptev Sea waters and those from ice-related environments pointing towards a marine origin for sea-ice diazotrophs. Our results provide the first record of diazotrophs in the Central Arctic and suggest that microbial nitrogen fixation may occur north of 77ºN. To assess the significance of nitrogen fixation for the nitrogen budget of the Arctic Ocean and to identify the active nitrogen fixers, further biogeochemical and molecular biological studies are needed.

  13. Diazotroph Diversity in the Sea Ice, Melt Ponds, and Surface Waters of the Eurasian Basin of the Central Arctic Ocean

    Science.gov (United States)

    Fernández-Méndez, Mar; Turk-Kubo, Kendra A.; Buttigieg, Pier L.; Rapp, Josephine Z.; Krumpen, Thomas; Zehr, Jonathan P.; Boetius, Antje

    2016-01-01

    The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which encodes the iron protein of the nitrogenase enzyme. We amplified 529 nifH sequences from 26 samples of Arctic melt ponds, sea ice and surface waters. These sequences resolved into 43 clusters at 92% amino acid sequence identity, most of which were non-cyanobacterial phylotypes from sea ice and water samples. One cyanobacterial phylotype related to Nodularia sp. was retrieved from sea ice, suggesting that this important functional group is rare in the Central Arctic Ocean. The diazotrophic community in sea-ice environments appear distinct from other cold-adapted diazotrophic communities, such as those present in the coastal Canadian Arctic, the Arctic tundra and glacial Antarctic lakes. Molecular fingerprinting of nifH and the intergenic spacer region of the rRNA operon revealed differences between the communities from river-influenced Laptev Sea waters and those from ice-related environments pointing toward a marine origin for sea-ice diazotrophs. Our results provide the first record of diazotrophs in the Central Arctic and suggest that microbial nitrogen fixation may occur north of 77°N. To assess the significance of nitrogen fixation for the nitrogen budget of the Arctic Ocean and to identify the active nitrogen fixers, further biogeochemical and molecular biological studies are needed. PMID:27933047

  14. Diazotroph Diversity in the Sea Ice, Melt Ponds, and Surface Waters of the Eurasian Basin of the Central Arctic Ocean.

    Science.gov (United States)

    Fernández-Méndez, Mar; Turk-Kubo, Kendra A; Buttigieg, Pier L; Rapp, Josephine Z; Krumpen, Thomas; Zehr, Jonathan P; Boetius, Antje

    2016-01-01

    The Eurasian basin of the Central Arctic Ocean is nitrogen limited, but little is known about the presence and role of nitrogen-fixing bacteria. Recent studies have indicated the occurrence of diazotrophs in Arctic coastal waters potentially of riverine origin. Here, we investigated the presence of diazotrophs in ice and surface waters of the Central Arctic Ocean in the summer of 2012. We identified diverse communities of putative diazotrophs through targeted analysis of the nifH gene, which encodes the iron protein of the nitrogenase enzyme. We amplified 529 nifH sequences from 26 samples of Arctic melt ponds, sea ice and surface waters. These sequences resolved into 43 clusters at 92% amino acid sequence identity, most of which were non-cyanobacterial phylotypes from sea ice and water samples. One cyanobacterial phylotype related to Nodularia sp. was retrieved from sea ice, suggesting that this important functional group is rare in the Central Arctic Ocean. The diazotrophic community in sea-ice environments appear distinct from other cold-adapted diazotrophic communities, such as those present in the coastal Canadian Arctic, the Arctic tundra and glacial Antarctic lakes. Molecular fingerprinting of nifH and the intergenic spacer region of the rRNA operon revealed differences between the communities from river-influenced Laptev Sea waters and those from ice-related environments pointing toward a marine origin for sea-ice diazotrophs. Our results provide the first record of diazotrophs in the Central Arctic and suggest that microbial nitrogen fixation may occur north of 77°N. To assess the significance of nitrogen fixation for the nitrogen budget of the Arctic Ocean and to identify the active nitrogen fixers, further biogeochemical and molecular biological studies are needed.

  15. Amplicon-Based Pyrosequencing Reveals High Diversity of Protistan Parasites in Ships' Ballast Water: Implications for Biogeography and Infectious Diseases.

    Science.gov (United States)

    Pagenkopp Lohan, K M; Fleischer, R C; Carney, K J; Holzer, K K; Ruiz, G M

    2016-04-01

    Ships' ballast water (BW) commonly moves macroorganisms and microorganisms across the world's oceans and along coasts; however, the majority of these microbial transfers have gone undetected. We applied high-throughput sequencing methods to identify microbial eukaryotes, specifically emphasizing the protistan parasites, in ships' BW collected from vessels calling to the Chesapeake Bay (Virginia and Maryland, USA) from European and Eastern Canadian ports. We utilized tagged-amplicon 454 pyrosequencing with two general primer sets, amplifying either the V4 or V9 domain of the small subunit (SSU) of the ribosomal RNA (rRNA) gene complex, from total DNA extracted from water samples collected from the ballast tanks of bulk cargo vessels. We detected a diverse group of protistan taxa, with some known to contain important parasites in marine systems, including Apicomplexa (unidentified apicomplexans, unidentified gregarines, Cryptosporidium spp.), Dinophyta (Blastodinium spp., Euduboscquella sp., unidentified syndinids, Karlodinium spp., Syndinium spp.), Perkinsea (Parvilucifera sp.), Opisthokonta (Ichthyosporea sp., Pseudoperkinsidae, unidentified ichthyosporeans), and Stramenopiles (Labyrinthulomycetes). Further characterization of groups with parasitic taxa, consisting of phylogenetic analyses for four taxa (Cryptosporidium spp., Parvilucifera spp., Labyrinthulomycetes, and Ichthyosporea), revealed that sequences were obtained from both known and novel lineages. This study demonstrates that high-throughput sequencing is a viable and sensitive method for detecting parasitic protists when present and transported in the ballast water of ships. These data also underscore the potential importance of human-aided dispersal in the biogeography of these microbes and emerging diseases in the world's oceans.

  16. Investigation of the microbial diversity of an extremely acidic, metal-rich water body (Lake Robule, Bor, Serbia

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    Stanković Srđan

    2014-01-01

    Full Text Available An investigation of the microbial diversity of the extremely acidic, metal-rich Lake Robule was carried out using culture-dependant and culture-independent (T-RFLP methods, and the ability of indigenous bacteria from the lake water to leach copper from a mineral concentrate was tested. T-RFLP analysis revealed that the dominant bacteria in lake water samples were the obligate heterotroph Acidiphilium cryptum (~50% of total bacteria and the iron-oxidizing autotroph Leptospirillum ferrooxidans (~40% The iron/sulfur-oxidizing autotroph Acidithiobacillus ferrooxidans had been reported to be the most abundant bacteria in the lake in an earlier study by other authors, but it was not detected in the present study using T-RFLP. Although it was isolated on solid media and detected in enrichment (bioleaching cultures. The presence of the two bacterial species detected by T-RFLP (L. ferrooxidans and A. cryptum was also confirmed by cultivation on solid media. The presence and relative abundance of bacteria inhabiting Lake Robule was explained by the physiological characteristics of the bacteria and the physico-chemical characteristics of the lake water. [Projekat Ministarstva nauke Republike Srbije, br. 176016 i br.173048

  17. Culturable bacterial diversity from a feed water of a reverse osmosis system, evaluation of biofilm formation and biocontrol using phages.

    Science.gov (United States)

    Belgini, D R B; Dias, R S; Siqueira, V M; Valadares, L A B; Albanese, J M; Souza, R S; Torres, A P R; Sousa, M P; Silva, C C; De Paula, S O; Oliveira, V M

    2014-10-01

    Biofilm formation on reverse osmosis (RO) systems represents a drawback in the application of this technology by different industries, including oil refineries. In RO systems the feed water maybe a source of microbial contamination and thus contributes for the formation of biofilm and consequent biofouling. In this study the planktonic culturable bacterial community was characterized from a feed water of a RO system and their capacities were evaluated to form biofilm in vitro. Bacterial motility and biofilm control were also analysed using phages. As results, diverse Protobacteria, Actinobacteria and Bacteroidetes were identified. Alphaproteobacteria was the predominant group and Brevundimonas, Pseudomonas and Mycobacterium the most abundant genera. Among the 30 isolates, 11 showed at least one type of motility and 11 were classified as good biofilm formers. Additionally, the influence of non-specific bacteriophage in the bacterial biofilms formed in vitro was investigated by action of phages enzymes or phage infection. The vB_AspP-UFV1 (Podoviridae) interfered in biofilm formation of most tested bacteria and may represent a good alternative in biofilm control. These findings provide important information about the bacterial community from the feed water of a RO system that may be used for the development of strategies for biofilm prevention and control in such systems.

  18. CRISPR Diversity in E. coli Isolates from Australian Animals, Humans and Environmental Waters.

    Directory of Open Access Journals (Sweden)

    Maxim S Sheludchenko

    Full Text Available Seventy four SNP genotypes and 54 E. coli genomes from kangaroo, Tasmanian devil, reptile, cattle, dog, horse, duck, bird, fish, rodent, human and environmental water sources were screened for the presence of the CRISPR 2.1 loci flanked by cas2 and iap genes. CRISPR 2.1 regions were found in 49% of the strains analysed. The majority of human E. coli isolates lacked the CRISPR 2.1 locus. We described 76 CRISPR 2.1 positive isolates originating from Australian animals and humans, which contained a total of 764 spacer sequences. CRISPR arrays demonstrated a long history of phage attacks especially in isolates from birds (up to 40 spacers. The most prevalent spacer (1.6% was an ancient spacer found mainly in human, horse, duck, rodent, reptile and environmental water sources. The sequence of this spacer matched the intestinal P7 phage and the pO111 plasmid of E. coli.

  19. Longitudinal study of microbial diversity and seasonality in the Mexico City metropolitan area water supply system.

    Science.gov (United States)

    Mazari-Hiriart, Marisa; López-Vidal, Yolanda; Ponce-de-León, Sergio; Calva, Juan José; Rojo-Callejas, Francisco; Castillo-Rojas, Gonzalo

    2005-09-01

    In the Mexico City metropolitan area (MCMA), 70% of the water for 18 million inhabitants is derived from the Basin of Mexico regional aquifer. To provide an overview of the quality of the groundwater, a longitudinal study was conducted, in which 30 sites were randomly selected from 1,575 registered extraction wells. Samples were taken before and after chlorine disinfection during both the rainy and dry seasons (2000-2001). Microbiological parameters (total coliforms, fecal coliforms, streptococci, and Vibrio spp.), the presence of Helicobacter pylori, and physicochemical parameters, including the amount of trihalomethanes (THMs), were determined. Although microorganisms and inorganic and organic compounds were evident, they did not exceed current permissible limits. Chlorine levels were low, and the bacterial counts were not affected by chlorine disinfection. Eighty-four bacterial species from nine genera normally associated with fecal contamination were identified in water samples. H. pylori was detected in at least 10% of the studied samples. About 40% of the samples surpassed the THM concentration allowed by Mexican and U.S. regulations, with levels of chloroform being high. The quality of the water distributed to the MCMA varied between the rainy and dry seasons, with higher levels of pH, nitrates, chloroform, bromodichloromethane, total organic carbon, and fecal streptococci during the dry season. This study showed that the groundwater distribution system is susceptible to contamination and that there is a need for a strict, year-round disinfection strategy to ensure adequate drinking-water quality. This situation in one of the world's megacities may reflect what is happening in large urban centers in developing countries which rely on a groundwater supply.

  20. Comparison of Enterococcus species diversity in marine water and wastewater using Enterolert and EPA Method 1600.

    Science.gov (United States)

    Ferguson, Donna M; Griffith, John F; McGee, Charles D; Weisberg, Stephen B; Hagedorn, Charles

    2013-01-01

    EPA Method 1600 and Enterolert are used interchangeably to measure Enterococcus for fecal contamination of public beaches, but the methods occasionally produce different results. Here we assess whether these differences are attributable to the selectivity for certain species within the Enterococcus group. Both methods were used to obtain 1279 isolates from 17 environmental samples, including influent and effluent of four wastewater treatment plants, ambient marine water from seven different beaches, and freshwater urban runoff from two stream systems. The isolates were identified to species level. Detection of non-Enterococcus species was slightly higher using Enterolert (8.4%) than for EPA Method 1600 (5.1%). E. faecalis and E. faecium, commonly associated with human fecal waste, were predominant in wastewater; however, Enterolert had greater selectivity for E. faecalis, which was also shown using a laboratory-created sample. The same species selectivity was not observed for most beach water and urban runoff samples. These samples had relatively higher proportions of plant associated species, E. casseliflavus (18.5%) and E. mundtii (5.7%), compared to wastewater, suggesting environmental inputs to beaches and runoff. The potential for species selectivity among water testing methods should be considered when assessing the sanitary quality of beaches so that public health warnings are based on indicators representative of fecal sources.

  1. Comparison of Enterococcus Species Diversity in Marine Water and Wastewater Using Enterolert and EPA Method 1600

    Directory of Open Access Journals (Sweden)

    Donna M. Ferguson

    2013-01-01

    Full Text Available EPA Method 1600 and Enterolert are used interchangeably to measure Enterococcus for fecal contamination of public beaches, but the methods occasionally produce different results. Here we assess whether these differences are attributable to the selectivity for certain species within the Enterococcus group. Both methods were used to obtain 1279 isolates from 17 environmental samples, including influent and effluent of four wastewater treatment plants, ambient marine water from seven different beaches, and freshwater urban runoff from two stream systems. The isolates were identified to species level. Detection of non-Enterococcus species was slightly higher using Enterolert (8.4% than for EPA Method 1600 (5.1%. E. faecalis and E. faecium, commonly associated with human fecal waste, were predominant in wastewater; however, Enterolert had greater selectivity for E. faecalis, which was also shown using a laboratory-created sample. The same species selectivity was not observed for most beach water and urban runoff samples. These samples had relatively higher proportions of plant associated species, E. casseliflavus (18.5% and E. mundtii (5.7%, compared to wastewater, suggesting environmental inputs to beaches and runoff. The potential for species selectivity among water testing methods should be considered when assessing the sanitary quality of beaches so that public health warnings are based on indicators representative of fecal sources.

  2. Seasonal variations in the water quality, diversity and population ecology of intertidal macrofauna at an industrially influenced coast.

    Science.gov (United States)

    Vaghela, A; Bhadja, P; Ramoliya, J; Patel, N; Kundu, R

    2010-01-01

    Present communication reports the physico-chemical and biological quality of seawater and status of benthos of a highly industrialized shore of the north-western coastline of India. The coastal area considered for the present study, encircled by a variety of industries, was divided into two sampling sites and monitored for two consecutive years. Results of the water quality suggest that the obtained values of the physical and chemical parameters of seawater were comparable with data reported earlier. However, data obtained in the biological parameters of the seawater showed a declining trend. Results of the intertidal macrofaunal diversity studies revealed that the muddy upper littoral zones were represented by few species of coelenterata, porifera, arthropoda and mollusca. In the rocky-muddy middle littoral zones, gastropods, stars fishes, corallites, crabs, polychetes and tubeworms were present, whereas, predominantly rocky lower littoral zones were comparatively rich in macrofaunal diversity with small patches of coral colonies. However, when the results obtained in the present study was compared with that of earlier reported data, it was clear that the macrofaunal diversity indeed declined considerably over the years. This may be due to habitat destruction and habitat alteration in the coastline caused by increased anthropogenic activities in the area. Seasonal variations in the population density and abundance were observed in most of the faunal groups except in sessile corals and sponges. This may be due to local migration of the faunal groups towards deeper regions of the Gulf, as supported by the analysis of similarity, to avoid influx of freshwater during monsoon, and high temperature during summer and post monsoon seasons. The overall assessment of different parameters of this study revealed that though the physico- chemical characteristics of the seawater did not varied much from the earlier reported status, the biological characteristics of the seawater

  3. Spatial heterogeneity of zooplankton abundance and diversity in the Saudi coastal waters of the Southern Red Sea

    Science.gov (United States)

    Al-Aidaroos, Ali; El-Sherbiny, Mohsen; Mantha, Gopikrishna

    2013-04-01

    The horizontal distribution, abundance and diversity of zooplankton has been studied at 50 stations along the Saudi coastal waters of the southern Red Sea (27 stations around Farasan archipelago, 9 around Al-Qunfodah and 14 around Al-Lith) during March-April 2011 using a plankton net of 150 µm. The zooplankton standing crop fluctuated between 1058 and 25787 individuals/m3 with an average of 5231 individuals/m3. Zooplankton was dominated by holoplanktonic forms that representing 80.26 % of total zooplankton, while meroplanktonic constituting 19.74% and dominated by mollusc larvae. Copepods appeared to be the predominant component, formed an average of 69.69 % of the total zooplankton count followed by chaetognaths and urochordates (4.5 and 4.1% of total zooplankton respectively). A total of 100 copepods species in addition to several species of other planktonic groups (cladocerans, chaetognaths, urochordates) were recorded in the study area. The copepod diversity decreased northward (94, 69 and 62 species at Farasan, Al-Qunfodah and Al-Lith respectively). In general, adult cyclopoid copepods dominated the zooplankton community in term of abundance and species number (19.55 %, 65 species) with dominance of Oncaea media, Oithona similis and Farranula carinata followed by adult calanoid copepods (19.38%, 35 species) with dominance of Paracalanus aculeatus, Clausocalanus minor, Acartia (Acanthacartia) fossae and Centropages orsinii. Harapacticoids densities were low in abundance, represented only by 5 species and dominated mainly by Euterpina acutifronis. Some copepod species decreased northward: Acartia amboinensis, Canthocalanus pauper, Labidocera acuta, Corycaeus flaccus, C. typicus, C. agilis, C. catus, C. giesbrechti, C. latus, C. furcifer and Euterpina acutifronis, while others increased northward (Acartia fossae, Undinula vulgaris and Centropages orsinii). Among copepod orders, Monstrilloida and Siphonostomatoida were observed only in southern area (Farasan

  4. Diversity of Salmonella spp. serovars isolated from the intestines of water buffalo calves with gastroenteritis

    Directory of Open Access Journals (Sweden)

    Borriello Giorgia

    2012-10-01

    Full Text Available Abstract Background Salmonellosis in water buffalo (Bubalus bubalis calves is a widespread disease characterized by severe gastrointestinal lesions, profuse diarrhea and severe dehydration, occasionally exhibiting a systemic course. Several Salmonella serovars seem to be able to infect water buffalo, but Salmonella isolates collected from this animal species have been poorly characterized. In the present study, the prevalence of Salmonella spp. in water buffalo calves affected by lethal gastroenteritis was assessed, and a polyphasic characterization of isolated strains of S. Typhimurium was performed. Results The microbiological analysis of the intestinal contents obtained from 248 water buffalo calves affected by lethal gastroenteritis exhibited a significant prevalence of Salmonella spp. (25%, characterized by different serovars, most frequently Typhimurium (21%, Muenster (11%, and Give (11%. The 13 S. Typhimurium isolates were all associated with enterocolitis characterized by severe damage of the intestine, and only sporadically isolated with another possible causative agent responsible for gastroenteritis, such as Cryptosporidium spp., Rotavirus or Clostridium perfringens. Other Salmonella isolates were mostly isolated from minor intestinal lesions, and often (78% of cases isolated with other microorganisms, mainly toxinogenic Escherichia coli (35%, Cryptosporidium spp. (20% and Rotavirus (10%. The S. Typhimurium strains were characterized by phage typing and further genotyped by polymerase chain reaction (PCR detection of 24 virulence genes. The isolates exhibited nine different phage types and 10 different genetic profiles. Three monophasic S. Typhimurium (B:4,12:i:- isolates were also found and characterized, displaying three different phage types and three different virulotypes. The molecular characterization was extended to the 7 S. Muenster and 7 S. Give isolates collected, indicating the existence of different virulotypes also within

  5. Genetic diversity among toxigenic clostridia isolated from soil, water, meat and associated polluted sites in South India.

    Science.gov (United States)

    Sathish, S; Swaminathan, K

    2009-01-01

    To investigate the genetic diversity of toxigenic Clostridium strains isolated from soil, water, meat and its associated polluted sites of Southern India. A total of 27 identified isolates of six different toxigenic clostridial species including C. bifermentans , C. botulinum , C. chauvoei , C. ramosum , C. tetani and C. novyi were isolated and characterized by conventional DNA restriction digestion analysis (REA) and by whole-cell and excretory protein patterns on SDS-PAGE. The DNA fragment size ranged from 35-160 kilobases and the protein bands 30-200 KDa, followed by numerical analyses and phylogenetic analyses. Whole-cell protein banding pattern were unique with strains of C. chauvoei , C. novyi and C. ramosum . All the strains were heterogeneous and distinct in restriction digestion pattern and excretory protein patterns. These analyses contribute to the understanding of prevalence of toxigenic clostridial species and phylogeny within the species and assist in development of improved diagnostics and therapeutics for the treatment of clostridial infections.

  6. The diversity of PAH-degrading bacteria in a deep-sea water column above the Southwest Indian Ridge.

    Science.gov (United States)

    Yuan, Jun; Lai, Qiliang; Sun, Fengqin; Zheng, Tianling; Shao, Zongze

    2015-01-01

    The bacteria involved in organic pollutant degradation in pelagic deep-sea environments are largely unknown. In this report, the diversity of polycyclic aromatic hydrocarbon (PAH)-degrading bacteria was analyzed in deep-sea water on the Southwest Indian Ridge (SWIR). After enrichment with a PAH mixture (phenanthrene, anthracene, fluoranthene, and pyrene), nine bacterial consortia were obtained from depths of 3946-4746 m. While the consortia degraded all four PAHs when supplied in a mixture, when PAHs were tested individually, only phenanthrene supported growth. Thus, degradation of the PAH mixture reflected a cometabolism of anthracene, fluoranthene, and pyrene with phenanthrene. Further, both culture-dependent and independent methods revealed many new bacteria involved in PAH degradation. Specifically, the alpha and gamma subclasses of Proteobacteria were confirmed as the major groups within the communities. Additionally, Actinobacteria, the CFB group and Firmicutes were detected. Denaturing Gradient Gel Electrophoresis (DGGE) analysis showed that bacteria closely affiliated with Alcanivorax, Novosphingobium, and Rhodovulum occurred most frequently in different PAH-degrading consortia. By using general heterotrophic media, 51 bacteria were isolated from the consortia and of these 34 grew with the PAH mixture as a sole carbon source. Of these, isolates most closely related to Alterierythrobacter, Citricella, Erythrobacter, Idiomarina, Lutibacterium, Maricaulis, Marinobacter, Martelella, Pseudidiomarina, Rhodobacter, Roseovarius, Salipiger, Sphingopyxis, and Stappia were found to be PAH degraders. To the best of our knowledge, this is the first time these bacteria have been identified in this context. In summary, this report revealed significant diversity among the PAH-degrading bacteria in the deep-sea water column. These bacteria may play a role in PAH removal in deep-sea environments.

  7. Subsurface microbial diversity in deep-granitic-fracture water in Colorado

    Science.gov (United States)

    Sahl, J.W.; Schmidt, R.; Swanner, E.D.; Mandernack, K.W.; Templeton, A.S.; Kieft, Thomas L.; Smith, R.L.; Sanford, W.E.; Callaghan, R.L.; Mitton, J.B.; Spear, J.R.

    2008-01-01

    A microbial community analysis using 16S rRNA gene sequencing was performed on borehole water and a granite rock core from Henderson Mine, a >1,000-meter-deep molybdenum mine near Empire, CO. Chemical analysis of borehole water at two separate depths (1,044 m and 1,004 m below the mine entrance) suggests that a sharp chemical gradient exists, likely from the mixing of two distinct subsurface fluids, one metal rich and one relatively dilute; this has created unique niches for microorganisms. The microbial community analyzed from filtered, oxic borehole water indicated an abundance of sequences from iron-oxidizing bacteria (Gallionella spp.) and was compared to the community from the same borehole after 2 weeks of being plugged with an expandable packer. Statistical analyses with UniFrac revealed a significant shift in community structure following the addition of the packer. Phospholipid fatty acid (PLFA) analysis suggested that Nitrosomonadales dominated the oxic borehole, while PLFAs indicative of anaerobic bacteria were most abundant in the samples from the plugged borehole. Microbial sequences were represented primarily by Firmicutes, Proteobacteria, and a lineage of sequences which did not group with any identified bacterial division; phylogenetic analyses confirmed the presence of a novel candidate division. This "Henderson candidate division" dominated the clone libraries from the dilute anoxic fluids. Sequences obtained from the granitic rock core (1,740 m below the surface) were represented by the divisions Proteobacteria (primarily the family Ralstoniaceae) and Firmicutes. Sequences grouping within Ralstoniaceae were also found in the clone libraries from metal-rich fluids yet were absent in more dilute fluids. Lineage-specific comparisons, combined with phylogenetic statistical analyses, show that geochemical variance has an important effect on microbial community structure in deep, subsurface systems. Copyright ?? 2008, American Society for Microbiology

  8. Methane seep in shallow-water permeable sediment harbors high diversity of anaerobic methanotrophic communities, Elba, Italy

    Directory of Open Access Journals (Sweden)

    S Emil Ruff

    2016-03-01

    Full Text Available The anaerobic oxidation of methane (AOM is a key biogeochemical process regulating methane emission from marine sediments into the hydrosphere. AOM is largely mediated by consortia of anaerobic methanotrophic archaea (ANME and sulfate-reducing bacteria (SRB, and has mainly been investigated in deep-sea sediments. Here we studied methane seepage at four spots located at 12 m water depth in coastal, organic-carbon depleted permeable sands off the Island of Elba (Italy. We combined biogeochemical measurements, sequencing-based community analyses and in situ hybridization to investigate the microbial communities of this environment. Increased alkalinity, formation of free sulfide and nearly stoichiometric methane oxidation and sulfate reduction rates up to 200 nmol g-1 day-1 indicated the predominance of sulfate-coupled AOM. With up to 40 cm thickness the zones of AOM activity were unusually large and occurred in deeper sediment horizons (20–50 cm below seafloor as compared to diffusion-dominated deep-sea seeps, which is likely caused by advective flow of pore water due to the shallow water depth and permeability of the sands. Hydrodynamic forces also may be responsible for the substantial phylogenetic and unprecedented morphological diversity of AOM consortia inhabiting these sands, including the clades ANME-1a/b, ANME-2a/b/c, ANME-3 and their partner bacteria SEEP-SRB1a and SEEP-SRB2. High microbial dispersal, the availability of diverse energy sources and high habitat heterogeneity might explain that the emission spots shared few microbial taxa, despite their physical proximity. Although the biogeochemistry of this shallow methane seep was very different to that of deep-sea seeps, their key functional taxa were very closely related, which supports the global dispersal of key taxa and underlines strong selection by methane as the predominant energy source. Mesophilic, methane-fueled ecosystems in shallow-water permeable sediments may comprise

  9. Prevalence and diversity of Aeromonas and Vibrio spp. in coastal waters of Southern Italy

    DEFF Research Database (Denmark)

    Dumontet, S.; Krovacek, K.; Svenson, S.B.

    2000-01-01

    and A. caviae. Furthermore, the antibiotic resistance patterns of isolated bacteria showed the presence of a number of resistant strains among the isolates. In order to discriminate the isolates on the basis of their biochemical profiles and/or antibiotic resistance patterns, cluster analysis...... was carried out which showed that no unique assay could fully discern these isolates. However, the best discrimination resulted from complete pattern profile based on both biochemical profiles and antibiotic resistance patterns.......% of samples were positive for Vibrio spp. It was interesting to note that 38% of the positive stations for both Aeromonas and Vibrio spp. showed a fecal coliform contamination of water at bacterial indicators (such as fecal...

  10. Comparing and Selecting Water-transfering Schemes of Diversion Canal for Beizhao Yellow River Diversion Project%北赵引黄工程引水渠输水方案的比选

    Institute of Scientific and Technical Information of China (English)

    张艳玲

    2012-01-01

    引水渠是整个灌区的渠首,规划的是否合理,关系到灌区的灌溉效益和投资、施工和管理的难易程度等。文中根据引水渠的布置原则,结合长远管理和规划等因素,坚持“多口引水”原则,保证灌区在黄河脱流的情况下也能引上水,对北赵引黄工程引水渠输水方案进行了比较,经综合比较,最终选出一种合理的输水方案。%The diversion canal is the canal head works of a irrigation district. Whether its planning is reasonable is related to the district's economic benefit, investment, construction and difficult or easy degree of management. According to the principle of diversion canal layout, in combination with several factors including long-term management, planning etc, adhering to the principle of diversion by multi-intake, and to ensure water diversion under the condition that fiver flow separates from the river bank, the paper conducts the comparison of water transfer schemes for Beizhuo Yellow River Diversion Project. Through comprehensive analysis, at last a reasonable scheme is selected.

  11. Ichthyofaunal Diversity and Water Quality in the Kangsabati Reservoir, West Bengal, India

    Directory of Open Access Journals (Sweden)

    Amalesh Bera

    2014-01-01

    Full Text Available The ichthyofauna in relation to water quality was studied on monthly basis from March, 2010 to February, 2011 in the Kangsabati Reservoir, West Bengal. The study revealed that physicochemical parameters of Kangsabati Reservoir were congenial for 39 fish species of commercial importance, belonging to 7 orders, 15 families, and 26 genera. The Cypriniformes were dominant with 17 species, followed by Siluriformes and Perciformes, with 7 species each, Channiformes with 3 species, Osteoglossiformes and Synbranchiformes with 2 species each, and Anguilliformes with 1 species. Regarding their conservation status, 27 species were of least concern, 1 species was vulnerable, 6 species were near threatened, 1 species was data deficient, and 4 species were not evaluated (IUCN-Version 2014.1. Economical values have also been evaluated. Water parameters such as temperature, pH, alkalinity, dissolved oxygen, hardness, free CO2, salinity, total inorganic nitrogen, and phosphate were recorded and found suitable for fish production. Conductivity, transparency, and high chloride level are minor limiting factor that may needs rectification for improved fisheries management.

  12. Distribution and diversity of a protist predator Cryothecomonas (Cercozoa) in Arctic marine waters.

    Science.gov (United States)

    Thaler, Mary; Lovejoy, Connie

    2012-01-01

    Heterotrophic nanoflagellates (HNFs) are key components in microbial food webs, potentially influencing community composition via top-down control of their favored prey or host. Marine cercozoan Cryothecomonas species are parasitoid and predatory HNFs that have been reported from ice, sediments, and the water column. Although Cryothecomonas is frequently reported from Arctic and subarctic seas, factors determining its occurrence are not known. We investigated the temporal and geographic distribution of Cryothecomonas in Canadian Arctic seas during the summer and autumn periods from 2006 to 2010. We developed a Cryothecomonas-specific fluorescent in situ hybridization (FISH) probe targeting ribosomal 18S rRNA to estimate cell concentrations in natural and manipulated samples. Comparison of simple and partial correlation coefficients showed that salinity, depth, and overall community biomass are important factors determining Cryothecomonas abundance. We found no evidence of parasitism in our samples. Hybridized cells included individuals smaller than any formally described Cryothecomonas, suggesting the presence of novel taxa or unknown life stages in this genus. A positive relationship between Cryothecomonas abundance and ice and meltwater suggests that it is a sensitive indicator of ice melt in Arctic water columns.

  13. Water quality and microbial diversity in cisterns from semiarid areas in Brazil.

    Science.gov (United States)

    Alves, Fellipe; Köchling, Thorsten; Luz, Julio; Santos, Sylvana Melo; Gavazza, Savia

    2014-09-01

    Harvesting rainwater is a common practice worldwide, particularly in areas with no access to a public water supply or insufficient groundwater reserves. More than two million people living in semiarid regions of Brazil consume rainwater stored in cisterns, and little information is available regarding the water quality. Despite the initial good quality of the rainwater, its harvest and storage can introduce contaminants that must be eliminated before consumption. To evaluate the influence of handling, cistern age and precipitation on the quality of harvested rainwater, we monitored seven cisterns in the semiarid Brazilian Northeast over 4 years. Microbial and physicochemical parameters were monitored once a month, and denaturant gradient gel electrophoresis (DGGE) was performed at the end of the monitoring period. Coliform bacteria were detected in 100% of samples, while Escherichia coli were observed in 73.8%. The alkalinity and conductivity were the highest for the recently built cisterns due to the dissolution of construction materials. The DGGE of the 16S r DNA did not reveal the presence of E. coli. Instead, DGGE bands sequencing indicated that species primarily affiliated with Alphaproteobacteria were present in all cisterns, indicating the presence of microbial ecosystems capable of purifying and stabilizing the stored rainwater.

  14. Neighborhood diversity of potentially pathogenic bacteria in drinking water from the city of Maroua, Cameroon.

    Science.gov (United States)

    Healy-Profitós, Jessica; Lee, Seungjun; Mouhaman, Arabi; Garabed, Rebecca; Moritz, Mark; Piperata, Barbara; Lee, Jiyoung

    2016-06-01

    This study examined the spatial variation of potential gastrointestinal pathogens within drinking water sources and home storage containers in four neighborhoods in Maroua, Cameroon. Samples were collected from source (n = 28) and home containers (n = 60) in each study neighborhood. Pathogen contamination was assessed using quantitative polymerase chain reaction, targeting Campylobacter spp., Shiga toxin producing Escherichia coli (virulence genes, stx1 and stx2), and Salmonella spp. Microbial source tracking (MST) targeted three different host-specific markers: HF183 (human), Rum2Bac (ruminant) and GFD (poultry) to identify contamination sources. Staphylococcus aureus and the tetracycline-resistance gene (tetQ) were assessed to measure human hand contact and presence of antibiotic-resistant bacteria. Pathogen/MST levels were compared statistically and spatially, and neighborhood variation was compared with previously collected demographic information. All the test fecal markers and pathogens (except Arcobacter) were detected in home and source samples. Two neighborhoods tested positive for most pathogens/MST while the others only tested positive for one or two. Spatial variation of pathogens/MST existed between sources, storage containers, and neighborhoods. Differing population density and ethno-economic characteristics could potentially explain variation. Future research should explore the influence of demographic and ethno-economic factors on water quality during microbial risk assessments in urban Africa.

  15. Large enantiomeric excesses in primitive meteorites and the diverse effects of water in cosmochemical evolution.

    Science.gov (United States)

    Pizzarello, Sandra; Schrader, Devin L; Monroe, Adam A; Lauretta, Dante S

    2012-07-24

    Carbonaceous chondrites are meteoritic fragments of asteroids that avoided the geological reprocessing of larger planets and allow laboratory probing of early solar-nebula materials. Among these, Renazzo-type (CR) chondrites found in Antarctica appear remarkably pristine and are distinguished by abundant organic materials and water-soluble molecules such as amino acids and ammonia. We present a comprehensive analysis of the organic composition of selected CR meteorites of different petrographic classification and compare compounds' abundance and distribution as they may relate to asteroidal aqueous processing and concomitant evolution of the mineral phases. We found that several CR compounds such as amino acids and sugar alcohols are fully represented in stones with no or minimal water exposure indicating a formation that, if solar, preceded parent body processes. The most pristine CRs also revealed natal enantiomeric excesses (ee) of up to 60%, much larger than ever recorded. However, aqueous alteration appears to affect CR soluble organic composition and abundances, in particular some diastereomeric amino acids may gauge its extent by the consequent racemization of their ee.

  16. Effects of plant diversity on primary production and species interactions in brackish water angiosperm communities

    DEFF Research Database (Denmark)

    Salo, Tiina; Gustafsson, Camilla; Boström, Christoffer

    2009-01-01

    plant productivity in brackish water angiosperm communities, a 14 wk field experiment was conducted. Using a replacement design with a standardized initial aboveground biomass, shoots of Zostera marina, Potamogeton filiformis and P. perfoliatus were planted on a shallow, sandy bottom in replicated...... monocultures and all possible species combinations. Response variables included aboveground and belowground biomass, shoot density, space occupation and porewater nutrients. To determine whether selection and/or complementarity controlled productivity, additive partitioning and Di were calculated. Richness...... effects were species-specific and only increased the biomass production of P. perfoliatus and tuber production of P. filiformis, while species composition generally had a stronger effect on biomass production. Additive partitioning indicated a positive complementarity effect for the aboveground biomass...

  17. Encapsulated discrete octameric water cluster, 1D water tape, and 3D water aggregate network in diverse MOFs based on bisimidazolium ligands

    Science.gov (United States)

    Shi, Ruo-Bing; Pi, Min; Jiang, Shuang-Shuang; Wang, Yuan-Yuan; Jin, Chuan-Ming

    2014-08-01

    Four new metal-organic frameworks, [Zn(2-mBIM)2(SO3CF3)2·(H2O)4] (1), [Zn(BMIE)(1,4-BDC)]·(H2O)3 (2), [Cd(BIM)2(OH)(H2O)2(PF6)]·(H2O)4 (3), and [Cd(PA-BIM)2 (ClO4)2]·11.33H2O (4) (2-mBIM = bis(2-methylimidazol-1-yl)methane, BMIE = 1,2-bis[1-(2-methylimidazole)-diethoxy]ethane, BIM = bis(imidazol-1-yl)methane, and PA-BIM = 1,1-bis [(2-phenylazo)imidazol-1-yl]methane) have been prepared and structurally characterized. Complex 1 exhibits an infinite 1D cationic beaded-chain structure, which encapsulated discrete octameric water clusters that are comprised of a chair-like hexameric water cluster with two extra water molecules dangling on two diagonal vertices of the chair. Complex 2 forms a 1D infinite zigzag metal-organic chain structure with a 1D T4(0)A(4) water tape. Complexes 3 show a 2D grid-like sheet structure with the 1D water tape T4(0)A(0)2(0) motif. Complex 4 is a porous 3D MOF with tetrahedron-coordinated Cd(II) centers and trans-conformation PA-BIM ligands. These holes are occupied by a fascinating three-dimensional water clathrate network, which consists of cage-shaped structural tetradecameric water cluster (H2O)14 units and six independent bridged water molecules. The results suggest that the bisimidazolium ligands and anions play crucial roles in the formation of the different host structures and different guest water aggregations. Additionally, the thermal stabilities and photoluminescence spectra of the complexes have been discussed.

  18. Diversity of planetary systems in low-mass disks: Terrestrial-type planet formation and water delivery

    CERN Document Server

    Ronco, María Paula

    2014-01-01

    Several studies, observational and theoretical, suggest that planetary systems with only rocky planets should be the most common in the Universe. We study the diversity of planetary systems that might form around Sun-like stars in low-mass disks without giant planets. We focus on the formation process of terrestrial planets in the habitable zone (HZ) and analyze their water contents with the goal to determine systems of astrobiological interest. Besides, we study the formation of planets on wide orbits because they can be detected with the microlensing technique. N-body simulations of high resolution (embryos + planetesimals) are developed for a wide range of surface density profiles. The surface density profile combines a power law to the inside of the disk of the form r^{-gamma}, with an exponential decay to the outside. We adopt a disk of 0.03M_sun and values of gamma = 0.5, 1 and 1.5. All our simulations form planets in the HZ with different masses and final water contents depending on the 3 profiles. For...

  19. Prevalence and diversity of extended-spectrum-β-lactamase-producing Enterobacteriaceae from marine beach waters.

    Science.gov (United States)

    Maravić, Ana; Skočibušić, Mirjana; Cvjetan, Svjetlana; Šamanić, Ivica; Fredotović, Željana; Puizina, Jasna

    2015-01-15

    A total of 1,351 Enterobacteriaceae isolates from 144 seawater samples were collected over a four-year period from three public beaches in the eastern Adriatic Sea in Croatia. Approximately 35% of the strains were multidrug-resistant. BlaESBL genes were detected in 4.2% of the isolated Enterobacteriaceae, the main species of which were Escherichia coli, Enterobacter cloacae and Klebsiella pneumoniae. BlaTEM-1+SHV-12 was the most dominant genotype, followed by blaCTX-M-15.Raoultella terrigena and E. intermedius simultaneously harboured blaTEM-1,blaSHV-11/12 and blaCTX-M-15. Isolate fingerprinting revealed that marine E. coli isolates were clonally related to CTX-M-producing strains from a regional university hospital. These results indicate that marine beach waters are reservoirs of ESBL-producing Enterobacteriaceae and thus constitute a public health problem with further potential to act as mediators in gene flow between marine coastal areas and clinical settings. Copyright © 2014 Elsevier Ltd. All rights reserved.

  20. Diversity and abundance of water birds in a subarctic lake during three decades

    Directory of Open Access Journals (Sweden)

    Anders Klemetsen

    2013-12-01

    Full Text Available The numbers of divers, ducks, gulls, terns and waders in the 15 km2 oligotrophic lake Takvatn, North Norway were estimated six times during 1983-2012. Systematic mapping surveys were done by boat within the first week after ice-break in June. Twenty-one species were observed over the years and 12 were regarded as breeding on the lake. Red-breasted merganser Mergus serrator was the dominant diving bird, with estimated minimum number of pairs varying from 15 to 39 among years. Black-throated diver Gavia arctica (1-3 pairs, tufted duck Aythya fuligula (2-15 pairs and common scoter Melanitta nigra (1-5 pairs bred regularly, while velvet scoter Melanitta fusca (1-2 and goldeneye Bucephala clangula (2-4 were found in some years and mallard Anas platyrhynchos (1 pair and wigeon Anas penelope (1 pair in one year. Common gull Larus canus (6-30 pairs and arctic tern Sterna paradisaea (2-35 pairs bred in all years. Common sandpiper Tringa hypoleucos (3-9 pairs and redshank Tringa totanus (1-4 pairs were regular waders. Density variations of mergansers, gulls and terns are possibly related to density variations of three-spined sticklebacks Gasterosteus aculeatus, their dominant fish prey. The water birds are important links in the food web of the lake.

  1. Deconstructing responses of dragonfly species richness to area, nutrients, water plant diversity and forestry.

    Science.gov (United States)

    Honkanen, Merja; Sorjanen, Aili-Maria; Mönkkönen, Mikko

    2011-06-01

    Understanding large-scale variation in species richness in relation to area, energy, habitat heterogeneity and anthropogenic disturbance has been a major task in ecology. Ultimately, variation in species richness results from variation in individual species occupancies. We studied whether the individual species occupancy patterns are determined by the same candidate factors as total species richness. We sampled 26 boreal forest ponds for dragonflies (Odonata) and studied the effects of shoreline length, water vascular plant species density (WVPSD), availability of nutrients, intensity of forestry, amount of Sphagnum peat cover and pH on dragonfly species richness and individual dragonfly species. WVPSD and pH had a strong positive effect on species richness. Removal of six dragonfly species experiencing strongest responses to WVPSD cancelled the relationship between species richness and WVPSD. By contrast, removal of nine least observed species did not affect the relationship between WVPSD and species richness. Thus, our results showed that relatively common species responding strongly to WVPSD shaped the observed species richness pattern whereas the effect of least observed, often rare, species was negligible. Also, our results support the view that, despite of the great impact of energy on species richness at large spatial scales, habitat heterogeneity can still have an effect on species richness in smaller scales, even overriding the effects of area.

  2. The hydraulic characteristics of end-dump closure with the assistance of back- water-sill in diversion channel

    Institute of Scientific and Technical Information of China (English)

    陆贺; 胡志根; 刘全; 吕国轩; 叶建群; 任金明

    2016-01-01

    The river closure is a key step in the water dam construction, and the end-dump closure is a general way to cut off the river flow. The hydraulic characteristics at the closure gap are the main factors which affect the extent of closure difficulty. A method is proposed to reduce the difficulty of diversion channel closure by pre-building a closure structure called the backwater-sill at the downstream toe of the closure gap to change the flow pattern at the closure gap. The results of the physical model test and the three- dimensional numerical simulation indicate that the backwater-sill has the effects of raising the water level at the downstream toe of the closure gap, decreasing the water surface gradient, and reducing the closure drop and the flow velocity at the closure gap. The schemes with different dike widths, different closure gap widths, and different backwater-sill widths and heights are simulated. The results show that the height of the backwater-sill is the key factor affecting the hydro-indicators at the closure gap, while the influe- nce of the dike width, the closure gap width or the backwater-sill width can be ignored. The higher the backwater-sill is, the lower the hydro-indicators will be. Based on the numerical simulations and the physical model tests on the hydraulic characteristics at the closure gap of the backwater-sill assisted closure, the hydro-indicators and its calculation method are proposed to provide a theoreti- cal support for the river closure.

  3. [Space distribution characteristics and diversity analysis of phosphorus from overlying water and surface sediments in Taihu Lake].

    Science.gov (United States)

    Yuan, He-zhong; Shen, Ji; Liu, En-feng; Wang, Jian-jun; Meng, Xiang-hua

    2010-04-01

    The physi-chemical indexes in the overlying water and surface sediments of Taihu Lake, an eutrophic shallow lake, were determined. Then, the isopleth maps of spatial distribution of each parameter were illustrated. The results show that the concentrations of SRP, TP and TN in the overlying water and TOC, TN and TP as well as phosphorus fractions in surface sediments exhibit distinct diversity in spatially. The lowest values of TP and TN were 0.05, 0.88 mg x L(-1), respectively. The concentrations of Fe-P ranged from 29.13 to 258.31 mg x kg(-1). Besides, the northwest lake regions, high-load Ca-P was surveyed in the South Taihu Lake and East Taihu Lake with the highest value of 357.68 mg x kg(-1). The highest concentration of OP, 371.91 mg x kg(-1) was detected in the northwest region of the lake. IP takes up a greater proportion of TP than OP, and the highest value is approximately 50% higher than the lowest value. Fe-P has higher percentage in IP compared with Ca-P. Significant correlation between Fe-P, SRP and TP showed that Fe-P was the important phosphorus source of the overlying water (R: 0.49, 0.64). Furthermore, high correlation coefficients between TOC, TOC, C/N, TN, TP and phosphorus fractions suggest that higher concentration of organics was favor to the accumulation and burial of nutrients. The high-load contaminants exist principally in the Zhushan Bay, Wulihu Lake, Meiliang Bay and the northwest region of Taihu Lake. Significant heterogeneity of nutrients distribution in space of Taihu Lake connects with direct action of emission load of sewage. Simultaneously, different biogeochemical behaviors of each parameter play an important role.

  4. Comparisons of water quality parameters from diverse catchments during dry periods and following rain events.

    Science.gov (United States)

    Shah, Vikaskumar G; Dunstan, R Hugh; Geary, Phillip M; Coombes, Peter; Roberts, Timothy K; Rothkirch, Tony

    2007-08-01

    In this study, 12 catchments sites located along the north coast of New South Wales in Australia were grouped into the four categories of septic, cattle, sewage treatment plant (STP) and forested sites via cluster analysis based on their land use patterns. Water samples from all these sites were collected between October 2004 and June 2006 at a regular monthly interval and within 48 h of rain events. The samples were analyzed for bacterial counts including faecal coliform and total coliform; faecal sterols including coprostanol, epicoprostanol, cholesterol, cholestanol, 24-ethylcoprostanol, campesterol, stigmasterol and beta-sitosterol; and the elements including Na, Rb, Sr, Ag, Cd, Sn, Cs, Ba, Hg, Tl, Pb, Bi, U, Mg, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, K, As, Se, P and Mo. Over the course of the sampling period, the STP site had the highest average coprostanol level of 1693+/-567 ng/L which was significantly higher (prain events analyses of the data set revealed that elevated levels of both coprostanol and faecal coliforms were not exclusive to rain events. The average coprostanol levels in rain event samples at each site were not significantly different compared with the corresponding dry event samples. Conversely, faecal coliform numbers increased by 2-4 times in rain events samples from septic, cattle and forested sites, but did not alter in the STP site. Multivariate analyses identified coprostanol and Sr as major contributing factors for the discrimination of septic, cattle, STP and forested sites for both rain and dry events samples. It was clear that each land use type of catchment could be characterized by biochemical, bacteriological and elemental parameters.

  5. Diversity, distribution and spatial structure of the cold-water coral fauna of the Azores (NE Atlantic

    Directory of Open Access Journals (Sweden)

    A. Braga-Henriques

    2013-01-01

    Full Text Available Cold-water corals are widely considered as important structural components of benthic habitats, potentially enhancing local abundance in a variety of fish and invertebrate species. Yet, current knowledge of the taxonomic diversity and distribution patterns of these vulnerable, slow-growing organisms is scarce and fragmented, limiting the effectiveness of spatial management and conservation measures. We have conducted an exhaustive compilation of records of alcyonaceans, antipatharians, scleractinians and stylasterids available until the present day to assess the diversity, distribution, and spatial structure of coral assemblages in the Azores Exclusive Economic Zone (EEZ. The resulting database comprises 2501 entries concerning historical oceanographic expeditions and other published sources, as well as recent data from longline bycatch. Our taxonomic inventory appears to be fairly complete for the explored habitats, accounting for 164 species (79 alcyonaceans, 58 scleractinians, 18 antipatharians and 9 stylasterids, nine of which were new records. The Azores EEZ harbours a mixed coral fauna with several zoogeographic origins, showing the closest affinity with the Lusitanian–Mediterranean region. Very few apparent endemics were found (14%, and only in part supported by consistent sampling. Coral diversity is particularly high between 300 and 900 m depths, in areas recognized as traditional fishing grounds or exploitable fish habitat within the 100-mile limit of the EEZ. The composition of coral assemblages shows significant geographical structure among longitudinal sections of the study area at comparable depths (100–1500 m. There is no evidence of a possible role of the Mid-Atlantic Ridge or latitudinal effects underlying this pattern, which suggests that it may instead reflect assemblage variability among features. Stronger changes in species composition were found along the bathymetric gradient. Notwithstanding the mix of partially

  6. IMPACT OF JUTE RETTING ON NATIVE FISH DIVERSITY AND AQUATIC HEALTH OF ROADSIDE TRANSITORY WATER BODIES: AN ASSESSMENT IN EASTERN INDIA

    Directory of Open Access Journals (Sweden)

    Dipankar Ghosh

    2015-09-01

    Full Text Available Roadside transitory water bodies being manmade depressions have a great ecological and socio-economic importance from years. The effects of agricultural runoffs, jute retting, macro-phytes infestations and inadequate rainfall in changed climate often degrade transitory water bodies’ environment while the biodiversity have impacted severely because of population pressure, over exploitation and indiscriminate use of fine meshed fishing gears as a whole. Physico-chemical and biological analysis with fish species composition, relative abundance, diversity indices like species richness, evenness and Shannon-Wiener index were carried out for pre-, during and post-jute retting season and for year mean as a whole to assess impact of jute retting on the roadside transitory water body’s environmental health and indigenous fish diversity at Sahebnagar village in Nadia District, India. All the physico-chemical parameters barring biochemical oxygen demand and water transparency remained more or less same or marginally got little changed during those three seasons. As much as 19 native fish species with varied relative abundances and dominances were identified. Jute retting impacted lower native fish diversity indices like Shannon-Wiener index values (1.94 to 2.68 clearly indicated poor to moderate pollution status of the transitory water body in that area during monsoon in particular and throughout the year in general. So we opined there should be some control over the intense jute retting in the road side transitory water bodies for sustainable management of these manmade resources.

  7. Diversity and community structure of harpacticoid copepods associated with cold-water coral substrates in the Porcupine Seabight (North-East Atlantic)

    Science.gov (United States)

    Gheerardyn, Hendrik; de Troch, Marleen; Vincx, Magda; Vanreusel, Ann

    2010-03-01

    The influence of microhabitat type on the diversity and community structure of the harpacticoid copepod fauna associated with a cold-water coral degradation zone was investigated in the Porcupine Seabight (North-East Atlantic). Three substrate types were distinguished: dead fragments of the cold-water coral Lophelia pertusa, skeletons of the glass sponge Aphrocallistes bocagei and the underlying sediment. At the family level, it appears that coral fragments and underlying sediment do not harbour distinctly different assemblages, with Ectinosomatidae, Ameiridae, Pseudotachidiidae, Argestidae and Miraciidae as most abundant. Conclusions on assemblage structure and diversity of the sponge skeletons are limited as only two samples were available. Similarity analysis at species level showed a strong variation in the sediment samples, which did not harbour a distinctly different assemblage in opposition to the coral and sponge samples. Several factors (sediment infill on the hard substrates, mobility of the copepods, limited sample sizes) are proposed to explain this apparent lack of a distinct difference between the microhabitats. Coral fragments and sediment were both characterised by high species diversity and low species dominance, which might indicate that copepod diversity is not substantially influenced by hydrodynamical stress. The additive partitioning of species diversity showed that by adding locations species richness was greatly enhanced. The harpacticoid community in the cold-water coral degradation zone is highly diverse and includes 157 species, 62 genera and 19 families. Information from neighbouring soft-bottom regions is necessary to assess whether total species diversity is increased by the presence of these complex habitat-providing substrates.

  8. Computation and error analysis of discharge for the Lake Michigan Diversion Project in Illinois: 1997-99 water years

    Science.gov (United States)

    Duncker, James J.; Over, Thomas M.; Gonzalez, Juan A.

    2006-01-01

    Acoustic velocity meters (AVM's) and acoustic Doppler current profilers (ADCP's) were used to measure streamflow at four streamflow-gaging stations in the Chicago River system. The streamflow data were used to compute discharge and to determine the uncertainty in the computed annual mean discharge at each station for the Lake Michigan Diversion Project in Illinois. Descriptions of the instrumentation at each station, stage-area and index-velocity ratings, and methods utilized for computing discharge and estimating missing record are given. Daily mean and annual mean discharges were computed for each station for 1997-99 water years (WY's). A water year is defined as the 12-month period from October 1 through September 30. The water year is designated by the calender year in which it ends and which includes 9 of the 12 months. Thus, the year ending September 30, 1999, is called the 1999 water year. A first-order error analysis was applied to acoustic velocity meter (AVM) data, stage-area, and index-velocity ratings at each streamflow-gaging station. The error analysis results indicate that the uncertainty is sensitive to the value of uncertainty associated with acoustic Doppler cur-rent profiler (ADCP) discharge measurement data. At the Chicago River at Columbus Drive at Chicago, Illinois station for the 1997-99 WY's, the uncertainty, expressed as a standard deviation of the average annual discharge, ranged from 13 to 18 cubic feet per second (ft3/s) when ADCP uncertainty was not included, whereas total uncertainty ranged from 55 to 69 ft3/s when ADCP uncertainty was included. At the Chicago Sanitary and Ship Canal at Romeoville, Illinois station for the 1997-99 WY's, the uncertainty ranged from 18 to 20 ft3/s when ADCP uncertainty was not included, whereas it ranged from 64 to 68 ft3/s when it was included. At the Calumet River below O'Brien Lock and Dam at Chicago, Illinois station for the 1997-99 WY's, the uncertainty ranged from 13 to 22 ft3/s when ADCP

  9. Effects of water diversion and climate change on the Rur and Meuse in low-flow situations

    NARCIS (Netherlands)

    Pyka, Christiane; Jacobs, Cor; Breuer, Roman; Elbers, Jan; Nacken, Heribert; Sewilam, Hani; Timmerman, Jos

    2016-01-01

    Water scarcity is one of the problems in water management that hinders European rivers in reaching a good ecological status as defined in the European Water Framework Directive. Water scarcity often coincides with high water temperature and low water quality. High water temperatures decrease the

  10. Abundance and diversity of ammonia-oxidizing archaea and bacteria on granular activated carbon and their fates during drinking water purification process.

    Science.gov (United States)

    Niu, Jia; Kasuga, Ikuro; Kurisu, Futoshi; Furumai, Hiroaki; Shigeeda, Takaaki; Takahashi, Kazuhiko

    2016-01-01

    Ammonia is a precursor to trichloramine, which causes an undesirable chlorinous odor. Granular activated carbon (GAC) filtration is used to biologically oxidize ammonia during drinking water purification; however, little information is available regarding the abundance and diversity of ammonia-oxidizing archaea (AOA) and bacteria (AOB) associated with GAC. In addition, their sources and fates in water purification process remain unknown. In this study, six GAC samples were collected from five full-scale drinking water purification plants in Tokyo during summer and winter, and the abundance and community structure of AOA and AOB associated with GAC were studied in these two seasons. In summer, archaeal and bacterial amoA genes on GACs were present at 3.7 × 10(5)-3.9 × 10(8) gene copies/g-dry and 4.5 × 10(6)-4.2 × 10(8) gene copies/g-dry, respectively. In winter, archaeal amoA genes remained at the same level, while bacterial amoA genes decreased significantly for all GACs. No differences were observed in the community diversity of AOA and AOB from summer to winter. Phylogenetic analysis revealed high AOA diversity in group I.1a and group I.1b in raw water. Terminal-restriction fragment length polymorphism analysis of processed water samples revealed that AOA diversity decreased dramatically to only two OTUs in group I.1a after ozonation, which were identical to those detected on GAC. It suggests that ozonation plays an important role in determining AOA diversity on GAC. Further study on the cell-specific activity of AOA and AOB is necessary to understand their contributions to in situ nitrification performance.

  11. New Mexico EPSCoR - Challenges of Integrating Diverse Water- Related Climate Data Into an Interoperable Geospatial Infrastructure

    Science.gov (United States)

    Hudspeth, W. B.; Benedict, K. K.; Gleasner, L.; Sanchez-Silva, R.

    2011-12-01

    New Mexico EPSCoR (NM EPSCoR) is a multi-faceted program aimed at improving New Mexico's capacity to carry out scientific research. Funded by the National Science Foundation, the current project focuses on science research into the impacts of climate change on mountain sources of water in northern New Mexico. It does so by investing in the state's research infrastructure, cyber-infrastructure, and human infrastructure. The goal is to provide the tools necessary to a quantitative, science-driven discussion of difficult water policy options facing the state in the future. This report discusses the leadership role taken by the Earth Data Analysis Center, University of New Mexico in developing computational interoperability capacity that will allow for wider use and sharing of climate data. Two linked activities are described. First we evaluate the challenges of integrating a highly diverse collection of climate data, from a variety of researchers in the state, into the Geographic Storage Transformation and Retrieval Engine (GSTORE), a distributed platform aimed to provide large-scale vector and raster data discovery, subsetting, and delivery via web services, mainly based on Open Geospatial Consortium (OGC) and REST web service standards. In the State of New Mexico, the platform has been successfully implemented using a variety of Open Source tools and deployed on multi-terabyte data repositories including the Resource Geographic Information System (RGIS) clearinghouse and the NM ESPCoR/NSF Science data portal. Second, while FGDC compliant metadata is required for every dataset, many datasets for EPSCoR have been created without metadata. We report on the iterative, collaborative steps between various climate researchers and EDAC staff in building metadata templates that can facilitate the rapid ingest of new data into the GSTORE archive.

  12. A combined cultivation and cultivation-independent approach shows high bacterial diversity in water-miscible metalworking fluids.

    Science.gov (United States)

    Lodders, Nicole; Kämpfer, Peter

    2012-06-01

    Ten metalworking fluids (MWF) and seven water preparation basis samples (WPB) were taken from five industrial plants in Germany. Total cells (TCC) and colony forming units (CFU) were counted, strains were isolated and their 16S rRNA gene was sequenced. Additionally, DNA was extracted directly from the samples, and clone libraries of 16S rRNA genes were built and gene sequenced. TCC ranged from 7.6×10(4) TCC/mL MWF to 1.6×10(8) TCC/mL MWF, and from 4.6×10(2) TCC/mL WPB to 7.8×10(7) TCC/mL WPB. The CFU showed similar but often lower results. A total of 70 isolates and 732 clones were 16S rRNA gene sequenced and all isolates, as well as 183 of the nearly full length 16S rRNA of these clones, were gene sequenced. A total of 98 different genera were detected in all 17 samples. The number of genera within each sample varied highly, with 1-22 genera per sample. The dominant genera in MWF were Leucobacter, Desemzia, Sphingomonas and Wautersiella. From these, only Sphingomonas was detected in WPB as well. This study showed that MWF can harbour a high bacterial diversity, which differs significantly from the bacterial flora of the corresponding WPB.

  13. Diversity in the Globally Distributed Diatom Genus Chaetoceros (Bacillariophyceae): Three New Species from Warm-Temperate Waters

    Science.gov (United States)

    Boonprakob, Atchaneey; Gaonkar, Chetan C.; Kooistra, Wiebe H. C. F.; Lange, Carina B.; Hernández-Becerril, David; Chen, Zuoyi; Moestrup, Øjvind; Lundholm, Nina

    2017-01-01

    Chaetoceros is one of the most species rich, widespread and abundant diatom genera in marine and brackish habitats worldwide. It therefore forms an excellent model for in-depth biodiversity studies, assessing morphological and genetic differentiation among groups of strains. The global Chaetoceros lorenzianus complex presently comprises three species known to science. However, our recent studies have shown that the group includes several previously unknown species. In this article, 50 strains, mainly from high latitudes and from warm-temperate waters, were examined morphologically and genetically and the results compared with those of field studies from elsewhere. The strains clustered into five groups, two of which are formed by C. decipiens Cleve and C. mitra (Bailey) Cleve, respectively. Their species descriptions are emended based on samples collected close to the type localities. The three other groups are formed by new species, C. elegans sp. nov., C. laevisporus sp. nov. and C. mannaii sp. nov. Characters used to distinguish each species are: orientation of setae, shape and size of the apertures, shape, size and density of the poroids on the setae and, at least in some species, characters of the resting spores. Our aim is to cover the global species diversity in this complex, as correct species delineation is the basis for exploring biodiversity, distribution of organisms, interactions in the food web and effects of environmental changes. PMID:28085887

  14. Genetic diversity and temporal variation in the cyanophage community infecting marine Synechococcus species in Rhode Island's coastal waters.

    Science.gov (United States)

    Marston, Marcia F; Sallee, Jennifer L

    2003-08-01

    The cyanophage community in Rhode Island's coastal waters is genetically diverse and dynamic. Cyanophage abundance ranged from over 10(4) phage ml(-1) in the summer months to less then 10(2) phage ml(-1) during the winter months. Thirty-six distinct cyanomyovirus g20 genotypes were identified over a 3-year sampling period; however, only one to nine g20 genotypes were detected at any one sampling date. Phylogenetic analyses of g20 sequences revealed that the Rhode Island cyanomyoviral isolates fall into three main clades and are closely related to other known viral isolates of Synechococcus spp. Extinction dilution enrichment followed by host range tests and PCR restriction fragment length polymorphism analysis was used to detect changes in the relative abundance of cyanophage types in June, July, and August 2002. Temporal changes in both the overall composition of the cyanophage community and the relative abundance of specific cyanophage g20 genotypes were observed. In some seawater samples, the g20 gene from over 50% of isolated cyanophages could not be amplified by using the PCR primer pairs specific for cyanomyoviruses, which suggested that cyanophages in other viral families (e.g., Podoviridae or Siphoviridae) may be important components of the Rhode Island cyanophage community.

  15. Genetic diversity among toxigenic clostridia isolated from soil, water, meat and associated polluted sites in South India

    Directory of Open Access Journals (Sweden)

    Sathish S

    2009-01-01

    Full Text Available Purpose: To investigate the genetic diversity of toxigenic Clostridium strains isolated from soil, water, meat and its associated polluted sites of Southern India. Materials and Methods: A total of 27 identified isolates of six different toxigenic clostridial species including C. bifermentans , C. botulinum , C. chauvoei , C. ramosum , C. tetani and C. novyi were isolated and characterized by conventional DNA restriction digestion analysis (REA and by whole-cell and excretory protein patterns on SDS-PAGE. Results: The DNA fragment size ranged from 35-160 kilobases and the protein bands 30-200 KDa, followed by numerical analyses and phylogenetic analyses. Whole-cell protein banding pattern were unique with strains of C. chauvoei , C. novyi and C. ramosum . All the strains were heterogeneous and distinct in restriction digestion pattern and excretory protein patterns. Conclusion: These analyses contribute to the understanding of prevalence of toxigenic clostridial species and phylogeny within the species and assist in development of improved diagnostics and therapeutics for the treatment of clostridial infections.

  16. Climate change and environmental water reallocation in the Murray-Darling Basin: Impacts on flows, diversions and economic returns to irrigation

    Science.gov (United States)

    Kirby, J. M.; Connor, J.; Ahmad, M. D.; Gao, L.; Mainuddin, M.

    2014-10-01

    Increasing river environment degradation from historical growth in withdrawal is leading to reallocation of water from irrigation in many basins. We examine how potential reduction in irrigation allocations under a newly enacted environmental water plan for the Murray Darling Basin in Australia, in combination with projected climate change, impact on flows, diversions and the economic returns to irrigation. We use an integrated hydrology-economics model capable of simulating the year-to-year variability of flows, diversions, and economic returns to model three levels of reallocation (2400, 2750 and 3200 GL) under the historical climate, and under a dry, a median and a wet climate change projection. Previous assessments of the reallocation plan do not address climate change impacts, nor the impact of year to year variability in flows on economic returns. The broad results of this analysis are that estimated river flows and diversions are more sensitive to the range of climate change projections than to the range of diversion reallocation scenarios considered. The projected median climate change more or less removes from flows the gains to the environment resulting from reallocation. Reallocations only in combination with no climate change, or climate change at the wetter end of the range of projections, will lead to flows greater than those experienced under the water management regime prior to reallocation. The reduction in economic returns to irrigation is less than the reduction in water available for irrigation: a 25% reduction in the annual average water availability is estimated to reduce the annual average gross value of irrigated agricultural production by about 10%. This is consistent with expectation of economic theory (since more marginal activities are reduced first) and also with observations of reduced water availability and returns in the recent drought in the Murray-Darling Basin. Irrigation returns vary less across the range of climate change

  17. Efficacy of a sensory deterrent and pipe modifications in decreasing entrainment of juvenile green sturgeon (Acipenser medirostris) at unscreened water diversions.

    Science.gov (United States)

    Poletto, Jamilynn B; Cocherell, Dennis E; Mussen, Timothy D; Ercan, Ali; Bandeh, Hossein; Levent Kavvas, M; Cech, Joseph J; Fangue, Nann A

    2014-01-01

    Water projects designed to extract fresh water for local urban, industrial and agricultural use throughout rivers and estuaries worldwide have contributed to the fragmentation and degradation of suitable habitat for native fishes. The number of water diversions located throughout the Sacramento-San Joaquin watershed in California's Central Valley exceeds 3300, and the majority of these are unscreened. Many anadromous fish species are susceptible to entrainment into these diversions, potentially impacting population numbers. In the laboratory, juvenile green sturgeon (Acipenser medirostris) have been shown to have high entrainment rates into unscreened diversions compared with those of other native California fish species, which may act as a significant source of mortality for this already-threatened species. Therefore, we tested the efficacy of a sensory deterrent (strobe light) and two structural pipe modifications (terminal pipe plate and upturned pipe configuration) in decreasing the entrainment of juvenile green sturgeon (mean mass ± SEM = 162.9 ± 4.0 g; mean fork length = 39.4 ± 0.3 cm) in a large (>500 kl) outdoor flume fitted with a water-diversion pipe 0.46 m in diameter. While the presence of the strobe light did not affect fish entrainment rates, the terminal pipe plate and upturned pipe modifications significantly decreased the proportion of fish entrained out of the total number tested relative to control conditions (0.13 ± 0.02 and 0.03 ± 0.02 vs. 0.44 ± 0.04, respectively). These data suggest that sensory deterrents using visual stimuli are not an effective means to reduce diversion pipe interactions for green sturgeon, but that structural alterations to diversions can successfully reduce entrainment for this species. Our results are informative for the development of effective management strategies to mitigate the impacts of water diversions on sturgeon populations and suggest that effective restoration

  18. rpoD gene pyrosequencing for the assessment of Pseudomonas diversity in a water sample from the Woluwe River.

    Science.gov (United States)

    Sánchez, David; Matthijs, Sandra; Gomila, Margarita; Tricot, Catherine; Mulet, Magdalena; García-Valdés, Elena; Lalucat, Jorge

    2014-08-01

    A water sample from a noncontaminated site at the source of the Woluwe River (Belgium) was analyzed by culture-dependent and -independent methods. Pseudomonas isolates were identified by sequencing and analysis of the rpoD gene. Cultureindependent methods consisted of cloning and pyrosequencing of a Pseudomonas rpoD amplicon from total DNA extracted from the same sample and amplified with selective rpoD gene primers. Among a total of 14,540 reads, 6,228 corresponded to Pseudomonas rpoD gene sequences by a BLAST analysis in the NCBI database. The selection criteria for the reads were sequences longer than 400 bp, an average Q40 value greater than 25, and>85% identity with a Pseudomonas species. Of the 6,228 Pseudomonas rpoD sequences, 5,345 sequences met the established criteria for selection. Sequences were clustered by phylogenetic analysis and by use of the QIIME software package. Representative sequences of each cluster were assigned by BLAST analysis to a known Pseudomonas species when the identity with the type strain was greater than or equal to 96%. Twenty-six species distributed among 12 phylogenetic groups or subgroups within the genus were detected by pyrosequencing. Pseudomonas stutzeri, P. moraviensis, and P. simiae were the only cultured species not detected by pyrosequencing. The predominant phylogenetic group within the Pseudomonas genus was the P. fluorescens group, as determined by culture-dependent and -independent analyses. In all analyses, a high number of putative novel phylospecies was found: 10 were identified in the cultured strains and 246 were detected by pyrosequencing, indicating that the diversity of Pseudomonas species has not been fully described.

  19. The Diversity of PAH-degrading bacteria in a deep-sea water column above the Southwest Indian Ridge

    Directory of Open Access Journals (Sweden)

    Zongze eShao

    2015-08-01

    Full Text Available The bacteria involved in organic pollutant degradation in pelagic deep-sea environments are largely unknown. In this report, the diversity of polycyclic aromatic hydrocarbon ( PAH-degrading bacteria was analyzed in deep-sea water on the Southwest Indian Ridge (SWIR. After enrichment with a PAH mixture (phenanthrene, anthracene, fluoranthene and pyrene, 9 nine bacterial consortia were obtained from depths of 3946 m to 4746 m. PAH degradation occurred to all components of the mixture, but when using a single PAH as the sole carbon and energy source, only phenanthrene can be degraded obviously. This indicates the cometabolism of anthracene, fluoranthene and pyrene with phenanthreneWhile the consortia degraded all four PAHs when supplied in a mixture, when PAHs were tested individually, only phenanthrene supported growth. Thus, degradation of the PAH mixture reflected a cometabolism of anthracene, fluoranthene and pyrene with phenanthrene. Further, both culture-dependent and independent methods revealed many new bacteria involved in PAH degradation. Specifically, the alpha and gamma subclasses of Proteobacteria were confirmed as the major groups within the communities. Additionally, Actinobacteria, the CFB group and Firmicutes were detected. Denaturing Gradient Gel Electrophoresis (DGGE analysis showed that bacteria closely affiliated with Alcanivorax, Novosphingobium and Rhodovulum occurred most frequently in different PAH-degrading consortia. More than half of the isolates (34 of 51 isolates were confirmed to have the ability to grow with the PAH mixture By using general heterotrophic media, 51 bacteria were isolated from the consortia and of these 34 grew with the PAH mixture as a sole carbon source. Of these, isolates most closely related to Alterierythrobacter, Citricella, Erythrobacter, Idiomarina, Lutibacterium, Maricaulis, Marinobacter, Martelella, Pseudidiomarina, Rhodobacter, Roseovarius, Salipiger, Sphingopyxis and Stappia were found to

  20. Occurrence and diversity of Arcobacter spp. along the Llobregat River catchment, at sewage effluents and in a drinking water treatment plant.

    Science.gov (United States)

    Collado, Luis; Kasimir, Georg; Perez, Unai; Bosch, Albert; Pinto, Rosa; Saucedo, Gemma; Huguet, Josep M; Figueras, Maria Jose

    2010-06-01

    The presence of Arcobacter species in faecally contaminated environmental waters has previously been studied. However, the ability to eliminate Arcobacter during the water treatment processes that produce drinking water has been little studied. We have investigated the prevalence and diversity of Arcobacter spp. throughout the year at 12 sampling points in the Llobregat River catchment (Catalonia, Spain) including 3 sites at a drinking water treatment plant. Positive samples for Arcobacter spp., came predominantly from the most faecally polluted sites. Recovery rates from all sites were greater in the spring (91.7%) and summer (83.3%) than in autumn and winter (75.0% in both cases), but this trend was not statistically evaluated due to the limited number of samples. Among the 339 colonies analyzed, the most prevalent species by multiplex PCR and 16S rDNA restriction fragment length polymorphism were Arcobacter butzleri (80.2%), followed by Arcobacter cryaerophilus (19.4%) and Arcobacter skirrowii (0.3%). Isolates showed a high genotype diversity as determined by the enterobacterial repetitive intergenic consensus PCR. In fact, 91.2% (309/339) of the colonies had different genotypes, i.e. 248 of them among the 275 isolates of A. butzleri and 60 among the 63 isolates of A. cryaerophilus and 1 genotype of A. skirrowii. Arcobacter was never detected or isolated from finished drinking water, demonstrating that water treatment is effective in removing Arcobacter species.

  1. 南水北调东线工程水期权交易及其定价模型%Water rights option transaction and pricing model for Eastern Route of South-to-North Water Diversion Project

    Institute of Scientific and Technical Information of China (English)

    周进梅; 吴凤平

    2014-01-01

    提出将美式看跌水期权模式应用于南水北调东线工程水权交易市场,农业用水户运用二叉树定价模型对美式看跌期权各个阶段水价的波动以及期权价值进行分析,以做出对自身有益的决策。结果表明,南水北调东线工程水期权交易及其定价模型有利于激励节水灌溉技术的推广。%The American water rights put option model was applied to the water rights transaction market of the Eastern Route of the South-to-North Water Diversion Project .Agricultural water users used the binary tree pricing model to analyze the fluctuations of water price at various stages and the value of the American put option , in order to make decisions for their own benefit .This study shows that the water rights option transaction of the Eastern Route of South-to-North Water Diversion Project and the pricing model can contribute to the promotion of water-saving irrigation technology .

  2. Assessment of suitability of macrobenthic mollusc diversity to monitor water quality and shallow sediment quality in a tropical rehabilitated and non-rehabilitated wetland system

    Directory of Open Access Journals (Sweden)

    W.M. Dimuthu Nilmini Wijeyaratne

    2017-06-01

    Full Text Available Six sampling sites were selected to represent different land use types in the rehabilitated and non-rehabilitated areas of a recreational wetland in Sri Lanka to study the suitability of macrobenthic mollusc diversity to monitor spatial and temporal variation in physico-chemical parameters of water and shallow sediments. Individuals belonging to six families and eight species were recorded during the study. The significantly highest mean abundance (individuals of Bithynia tentaculata and Pila globosa were recorded in sites from the rehabilitated area and there was no significant temporal variation of mollusc abundance during the study.  The abundance and diversity of mollusc community showed significant spatial variations and this study identified that B. tentaculata and P. globosa can be used as possible bioindicators to detect changes in water and shallow sediment quality in tropical wetland ecosystems

  3. Modelling the response of shallow groundwater levels to combined climate and water-diversion scenarios in Beijing-Tianjin-Hebei Plain, China

    Science.gov (United States)

    Li, Xue; Ye, Si-Yuan; Wei, Ai-Hua; Zhou, Peng-Peng; Wang, Li-Heng

    2017-09-01

    A three-dimensional groundwater flow model was implemented to quantify the temporal variation of shallow groundwater levels in response to combined climate and water-diversion scenarios over the next 40 years (2011-2050) in Beijing-Tianjin-Hebei (Jing-Jin-Ji) Plain, China. Groundwater plays a key role in the water supply, but the Jing-Jin-Ji Plain is facing a water crisis. Groundwater levels have declined continuously over the last five decades (1961-2010) due to extensive pumping and climate change, which has resulted in decreased recharge. The implementation of the South-to-North Water Diversion Project (SNWDP) will provide an opportunity to restore the groundwater resources. The response of groundwater levels to combined climate and water-diversion scenarios has been quantified using a groundwater flow model. The impacts of climate change were based on the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset for future high (A2), medium (A1B), and low (B1) greenhouse gas scenarios; precipitation data from CMIP3 were applied in the model. The results show that climate change will slow the rate of decrease of the shallow groundwater levels under three climate-change scenarios over the next 40 years compared to the baseline scenario; however, the shallow groundwater levels will rise significantly (maximum of 6.71 m) when considering scenarios that combine climate change and restrictions on groundwater exploitation. Restrictions on groundwater exploitation for water resource management are imperative to control the decline of levels in the Jing-Jin-Ji area.

  4. Modelling the response of shallow groundwater levels to combined climate and water-diversion scenarios in Beijing-Tianjin-Hebei Plain, China

    Science.gov (United States)

    Li, Xue; Ye, Si-Yuan; Wei, Ai-Hua; Zhou, Peng-Peng; Wang, Li-Heng

    2017-03-01

    A three-dimensional groundwater flow model was implemented to quantify the temporal variation of shallow groundwater levels in response to combined climate and water-diversion scenarios over the next 40 years (2011-2050) in Beijing-Tianjin-Hebei (Jing-Jin-Ji) Plain, China. Groundwater plays a key role in the water supply, but the Jing-Jin-Ji Plain is facing a water crisis. Groundwater levels have declined continuously over the last five decades (1961-2010) due to extensive pumping and climate change, which has resulted in decreased recharge. The implementation of the South-to-North Water Diversion Project (SNWDP) will provide an opportunity to restore the groundwater resources. The response of groundwater levels to combined climate and water-diversion scenarios has been quantified using a groundwater flow model. The impacts of climate change were based on the World Climate Research Programme's (WCRP's) Coupled Model Intercomparison Project phase 3 (CMIP3) multi-model dataset for future high (A2), medium (A1B), and low (B1) greenhouse gas scenarios; precipitation data from CMIP3 were applied in the model. The results show that climate change will slow the rate of decrease of the shallow groundwater levels under three climate-change scenarios over the next 40 years compared to the baseline scenario; however, the shallow groundwater levels will rise significantly (maximum of 6.71 m) when considering scenarios that combine climate change and restrictions on groundwater exploitation. Restrictions on groundwater exploitation for water resource management are imperative to control the decline of levels in the Jing-Jin-Ji area.

  5. Discussion on water diversion hub layout in Budaer Hydropower Station%布达尔水电站工程引水枢纽布置探讨

    Institute of Scientific and Technical Information of China (English)

    吴建良

    2015-01-01

    Design process of Budaer Hydropower Station is not limited to a fixed form or fixed experience aiming at characteristics of rivers in Xinjiang mountainous area.Concrete conditions of projects are fully considered,design concepts are updated,and design ideas are expanded.Advantages and disadvantages of river sluice water diversion hub and river weir water diversion hub are concretely analyzed and compared according to project design examples.Necessity and rationality of the water diversion hub layout mode are correspondingly studied and discussed.%在布达尔水电站设计过程中,针对新疆山区河流的特点,不限于某一种固定形式,不拘泥于固定经验,充分考虑到工程项目的具体情况,更新设计观念,拓展设计思路,依据工程设计实例,对拦河闸式引水枢纽和拦河堰式引水枢纽的优缺点作了具体的分析比较,并对该引水枢纽布置方式的必要性及合理性进行了相应的研究和探讨。

  6. Genetic diversity of Ulva prolifera population in Qingdao coastal water during the green algal blooms revealed by microsatellite.

    Science.gov (United States)

    Li, Yue; Huang, Hong-Jia; Li, Hongye; Liu, Jiesheng; Yang, Weidong

    2016-10-15

    Green tides have occurred in Qingdao coast in China for seven consecutive years from 2007 to 2013. To provide information on the genetic structure of these blooms, 210 free-floating green algae samples isolated from the green tide in Qingdao coast on June 19, 2013 were identified based on the ITS, rbcL and 5S sequence, and genetic diversity was investigated by microsatellite markers. According to ITS, rbcL and 5S sequence, all the 210 samples belonged to Ulva prolifera. Nei's genetic diversity and Shannon index estimated using eight microsatellite markers indicated that the genetic diversity of U. prolifera population within Qingdao's green bloom in 2013 was low. Taking into account previous reports about life history and physiology of U. prolifera, we proposed that the limited origin area of the free-floating biomass and asexual reproduction of U. prolifera might be responsible for the lower diversity of free floating U. prolifera.

  7. Systematic Environmental Impact Assessment for Non-natural Reserve Areas: A Case Study of the Chaishitan Water Conservancy Project on Land Use and Plant Diversity in Yunnan, China

    Directory of Open Access Journals (Sweden)

    Zhi-Xin Zhu

    2017-06-01

    Full Text Available Environmental impact assessment (EIA before and after the establishment of a Water Conservancy Project (WCP is of great theoretical and practical importance for assessing the effectiveness of ecological restoration efforts. WCPs rehabilitate flood-damaged areas or other regions hit by disasters by controlling and redistributing surface water and groundwater. Using Geographic Information System (GIS and Composite Evaluation Index (CEI in predictive modeling, we studied the degree to which a WCP could change land use, plant communities, and species diversity in Yunnan, China. Via modeling, we quantified likely landscape pattern changes and linked them to naturality (i.e., the percentage of secondary vegetation types, diversity, and stability together with the human interferences (e.g., conservation or restoration project of an ecosystem. The value of each index was determined by the evaluation system, and the weight percentage was decided through Analytical Hierarchy Process (AHP. We found that minor land-use changes would occur after the Chaishitan WCP was theoretically established. The greatest decline was farmland (0.079%, followed by forest (0.066%, with the least decline in water bodies (0.020%. We found 1,076 vascular plant species (including subspecies, varieties and form belonging to 165 families and 647 genera in Chaishitan irrigation area before the water conservancy establishment. The naturality and diversity decreased 11.18 and 10.16% respectively. The CEI was 0.92, which indicated that Chaishitan WCP will enhance local landscape heterogeneity, and it will not deteriorate local ecological quality. Our study proposes a comprehensive ecological evaluation system for this WCP and further suggests the importance of including the ecological and environmental consequences of the WCP, along with the well-established socioeconomic evaluation systems for non-natural reserve areas. We conclude that the Chaishitan WCP will have minor

  8. Interactions of water and nitrogen addition on soil microbial community composition and functional diversity depending on the inter-annual precipitation in a Chinese steppe

    Institute of Scientific and Technical Information of China (English)

    SUN Liang-jie; QI Yu-chun; DONG Yun-she; HE Ya-ting; PENG Qin; LIU Xin-chao; JIA Jun-qiang; GUO Shu-fang; CAO Cong-cong

    2015-01-01

    Water and nitrogen are primary limiting factors in semiarid grassland ecosystems. Our knowledge is stil poor regarding the interactive effects of water and N addition on soil microbial communities, although this information is crucial to reveal the mechanisms of the terrestrial ecosystem response to global changes. We addressed this problem by conducting a ifeld experiment with a 15%surplus of the average rainfal under three levels of N addition (50, 100, and 200 kg N ha–1 yr–1) in two consecutive years in Inner Mongolia, China. Microbial community composition and functional diversity were analyzed based on phospholipid fatty acids (PLFA) and BIOLOG techniques, respectively. The results showed that water addition did not affect the soil microbial community composition, but much more yearly precipitation general y decreased the PLFA concentration, which implied a fast response of soil microbes to changes of water condition. Soil fungi was depressed only by N addition at the high level (200 kg N ha–1 yr–1) and without hydrologic leaching, while Gram-negative bacteria was suppressed probably by plant competition at high level N addition but with hydrologic leaching. The study found unilateral positive/negative interactions between water and N addition in affecting soil microbial community, however, climate condi-tion (precipitation) could be a signiifcant factor in disturbing the interactions. This study highlighted that:(1) The sustained effect of pulsed water addition was minimal on the soil microbial community composition but signiifcant on the microbial community functional diversity and (2) the complex interaction between water and N addition on soil microbial community related to the inter-annual variation of the climate and plant response.

  9. The Conception of Construction of Water culture Database of South-to-North Water Diversion Project%南水北调工程水文化数据库的建设构想

    Institute of Scientific and Technical Information of China (English)

    郭垚

    2015-01-01

    South-to-North water diversion project is rich in water culture, human resources and scientific support. These provide the conditions for the enrichment and development of water culture, which makes the construction of the water culture database of the South-to-North water diversion project is feasible. In the process of building water culture database, three construction principles and database construction step and service is the focus of concern.%南水北调工程丰富的水文化资源、人才和科研的支持,为水文化的丰富和发展提供了条件,使得南水北调工程水文化数据库的构建具有可行性。在构建水文化数据库的过程中,三个建设原则以及数据库建设步骤与服务是需要关注的重点。

  10. Antimicrobial Resistance, Virulence Factors and Genetic Diversity of Escherichia coli Isolates from Household Water Supply in Dhaka, Bangladesh

    NARCIS (Netherlands)

    P.K. Talukdar (Prabhat Kumar); M. Rahman (Mahdia); A. Nabi (Ashikun); Z. Islam (Zhahirul); M.M. Hoque (Mahfuzul); H.P. Endtz (Hubert)

    2013-01-01

    textabstractBackground: Unsafe water supplies continue to raise public health concerns, especially in urban areas in low resource countries. To understand the extent of public health risk attributed to supply water in Dhaka city, Bangladesh, Escherichia coli isolated from tap water samples collected

  11. Computing payment for ecosystem services in watersheds: An analysis of the Middle Route Project of South-to-North Water Diversion in China

    Institute of Scientific and Technical Information of China (English)

    Zhengju Dong; Yan Yah; Jing Duan; Xiao Fu; Qingrong Zhou; Xiang Huang; Xiangen Zhu; Jingzhu Zhao

    2011-01-01

    Payment for ecosystem services (PES) has attracted considerable attention as an economic incentive for promoting natural resource management recently.As emphasis has been placed on using the incentive-based mechanism by the central government,rapid progress on PES research and practice has been achieved.However PES still faces many difficulties.A key issue is the lack of a fully-fledged theory and method to clearly define the design scope,accounting and feasibility of PES criteria.An improved watershed criteria model was developed in light of research on PES practices in China,investigations on the water source area for the Middle Route Project of South-to-North Water Diversion and ecosystem services outflows theory.The basic principle of assessment is the direct and opportunity cost for ecological conservation and environmental protection in the water source area deduct nationally-financed PES and internal effect.Then the scope and the criteria methods were determined,and internal effect was put forward to define benefits brought from water source area.Finally,Shiyan City,which is the main water source area for the Project of Water Diversion,was analyzed by this model and its payment was calculated.The results showed that:(1) during 2003-2050,the total direct cost and opportunity cost would reach up to 262.70 billion and 256.33 billion Chinese Yuan (CNY,2000 constant prices),i.e.,50.61% and 49.38% of total cost,respectively; (2) Shiyan City would gain 0.23,0.06 and 0.03 CNY/m3 in 2014-2020,2021-2030,and 2031-2050,respectively.

  12. Two Novel Space-Time Coding Techniques Designed for UWB MISO Systems Based on Wavelet Transform

    Science.gov (United States)

    Zaki, Amira Ibrahim; El-Khamy, Said E.

    2016-01-01

    In this paper two novel space-time coding multi-input single-output (STC MISO) schemes, designed especially for Ultra-Wideband (UWB) systems, are introduced. The proposed schemes are referred to as wavelet space-time coding (WSTC) schemes. The WSTC schemes are based on two types of multiplexing, spatial and wavelet domain multiplexing. In WSTC schemes, four symbols are transmitted on the same UWB transmission pulse with the same bandwidth, symbol duration, and number of transmitting antennas of the conventional STC MISO scheme. The used mother wavelet (MW) is selected to be highly correlated with transmitted pulse shape and such that the multiplexed signal has almost the same spectral characteristics as those of the original UWB pulse. The two WSTC techniques increase the data rate to four times that of the conventional STC. The first WSTC scheme increases the data rate with a simple combination process. The second scheme achieves the increase in the data rate with a less complex receiver and better performance than the first scheme due to the spatial diversity introduced by the structure of its transmitter and receiver. The two schemes use Rake receivers to collect the energy in the dense multipath channel components. The simulation results show that the proposed WSTC schemes have better performance than the conventional scheme in addition to increasing the data rate to four times that of the conventional STC scheme. PMID:27959939

  13. Aguas Diversas. Derechos de agua y pluralidad legal en las comunidades andinas = Diverse Waters. Water rights and legal pluralism in Andean communities

    NARCIS (Netherlands)

    Boelens, R.A.

    2009-01-01

    Water rights and property relations have become pivotal issues in water debates, reforms and intervention programs. Governments, development agencies and expert centers tend to consider 'water rights' as merely standard black boxes that juxtapose the frameworks of positivist technical and economist

  14. Long-term effects of irrigation with waste water on soil AM fungi diversity and microbial activities: the implications for agro-ecosystem resilience.

    Directory of Open Access Journals (Sweden)

    Maria del Mar Alguacil

    Full Text Available The effects of irrigation with treated urban wastewater (WW on the arbuscular mycorrhizal fungi (AMF diversity and soil microbial activities were assayed on a long-term basis in a semiarid orange-tree orchard. After 43 years, the soil irrigated with fresh water (FW had higher AMF diversity than soils irrigated with WW. Microbial activities were significantly higher in the soils irrigated with WW than in those irrigated with FW. Therefore, as no negative effects were observed on crop vitality and productivity, it seems that the ecosystem resilience gave rise to the selection of AMF species better able to thrive in soils with higher microbial activity and, thus, to higher soil fertility.

  15. 南水北调中线工程水源区水土流失估算%Evaluating Water Source Reserve of South-to-North Water Diversion Center Line

    Institute of Scientific and Technical Information of China (English)

    刘雯; 杨爱荣; 蒋国富

    2011-01-01

    立足南水北调中线水源区独特的地理概况和水土流失的特征,利用GIS对空间数据处理和数值分析方法来估算当地的土壤侵蚀量.确定研究区域内土壤侵蚀量的各种不同等级,最终达到对水源区水土流失估算的目的,为南水北调中线工程水源区水土保持提供较为可靠的信息资源.%Based on the geography survey and the traits of soil erosion of south-to-north water diversion center line water source reserve, the article makes use of GIS to deal with spacial data and data analysis in order to evaluate local soil erosion situation, and make sure different classifications of it and at the end reach the aim of evaluating the water source reserve situation. To provide reliable information source for protecting the water source reserve of south-to-north water diversion center line.

  16. Eukaryotic community diversity and spatial variation during drinking water production (by seawater desalination) and distribution in a full-scale network

    KAUST Repository

    Belila, Abdelaziz

    2016-12-01

    Eukaryotic microorganisms are naturally present in many water resources and can enter, grow and colonize water treatment and transport systems, including reservoirs, pipes and premise plumbing. In this study, we explored the eukaryotic microbial community structure in water during the (i) production of drinking water in a seawater desalination plant and (ii) transport of the drinking water in the distribution network. The desalination plant treatment involved pre-treatment (e.g. spruce filters), reverse osmosis (RO) membrane filtration and post-treatment steps (e.g. remineralization). 454 pyrosequencing analysis of the 18S rRNA gene revealed a highly diverse (35 phyla) and spatially variable eukaryotic community during water treatment and distribution. The desalination plant feed water contained a typical marine picoeukaryotic community dominated by Stramenopiles, Alveolates and Porifera. In the desalination plant Ascomycota was the most dominant phylum (15.5% relative abundance), followed by Alveolata (11.9%), unclassified fungi clade (10.9%) and Porifera (10.7%). In the drinking water distribution network, an uncultured fungi phylum was the major group (44.0%), followed by Chordata (17.0%), Ascomycota (11.0%) and Arthropoda (8.0%). Fungi constituted 40% of the total eukaryotic community in the treatment plant and the distribution network and their taxonomic composition was dominated by an uncultured fungi clade (55%). Comparing the plant effluent to the network samples, 84 OTUs (2.1%) formed the core eukaryotic community while 35 (8.4%) and 299 (71.5%) constituted unique OTUs in the produced water at the plant and combined tap water samples from the network, respectively. RO membrane filtration treatment significantly changed the water eukaryotic community composition and structure, highlighting the fact that (i) RO produced water is not sterile and (ii) the microbial community in the final tap water is influenced by the downstream distribution system. The study

  17. IMPACTS OF THE SOUTH-TO-NORTH WATER DIVERSION PROJECTS (MIDDLE ROUTE)ON THE WATER ENVIRONMENT OF THE MIDDLE AND LOWER REACHES OF THE HANJIANG RIVER%南水北调工程(中段)对汉江中下游流域水环境的影响

    Institute of Scientific and Technical Information of China (English)

    FAN Bei-Lin; WAN Jian-Rong; ZHANG Jie; LIN Qiu-Sheng

    2006-01-01

    In this paper, according to the rule of unbalanced sediment transport and the analysis of field data, different water diversion schemes were theoretically studied, including the erosion and sedimentation trend as well as their impacts on the environment of the middle and lower reaches of the Hanjiang River. The results showed that the 95×108m3 water diversion scheme will cause less erosion and water level decrease than the 15×108m3 water diversion scheme. Using a water diversion scheme of 95×108m3,the decrease of water quantity can impact the river hydrodynamic regime substantially and the environments of the middle and lower reaches of the Hanjiang River will be greatly affected. It is therefore necessary to develop new water resources or build projects to meet the need of the environment and the needs for navigation.

  18. The use of genus-specific amplicon pyrosequencing to assess phytophthora species diversity using eDNA from soil and water in Northern Spain.

    Science.gov (United States)

    Català, Santiago; Pérez-Sierra, Ana; Abad-Campos, Paloma

    2015-01-01

    Phytophthora is one of the most important and aggressive plant pathogenic genera in agriculture and forestry. Early detection and identification of its pathways of infection and spread are of high importance to minimize the threat they pose to natural ecosystems. eDNA was extracted from soil and water from forests and plantations in the north of Spain. Phytophthora-specific primers were adapted for use in high-throughput Sequencing (HTS). Primers were tested in a control reaction containing eight Phytophthora species and applied to water and soil eDNA samples from northern Spain. Different score coverage threshold values were tested for optimal Phytophthora species separation in a custom-curated database and in the control reaction. Clustering at 99% was the optimal criteria to separate most of the Phytophthora species. Multiple Molecular Operational Taxonomic Units (MOTUs) corresponding to 36 distinct Phytophthora species were amplified in the environmental samples. Pyrosequencing of amplicons from soil samples revealed low Phytophthora diversity (13 species) in comparison with the 35 species detected in water samples. Thirteen of the MOTUs detected in rivers and streams showed no close match to sequences in international sequence databases, revealing that eDNA pyrosequencing is a useful strategy to assess Phytophthora species diversity in natural ecosystems.

  19. 引水式水电站压力前池的控制与检测%Control and Test of Pressure Forebay in Water Diversion Type Hydropower Station

    Institute of Scientific and Technical Information of China (English)

    张豹平

    2014-01-01

    Control and testing of forebay in water diversion type hydropower station as well as measures to improve economic benefits of water diversion type hydropower station are introduced in the paper in details.%本文对引水式水电站压力前池的控制、检测,以及提高引水式水电站经济效益的措施,作了详细介绍。

  20. Preliminary discussion on water pricing mechanism of Middle Route Project of South to North Water Diversion%南水北调中线工程水价形成机制初探

    Institute of Scientific and Technical Information of China (English)

    都瑞丰

    2015-01-01

    The formation process of water price for Middle Route Project of South to North Water Diversion is reviewed and the existed problems in the current pricing scheme are discussed. The principles in the water pricing process are demonstrated, inclu-ding the fair burden, cost recovery, reasonable profit, adjustable pricing mechanism and water resources allocation. A unified water pricing should be carried on for the same water quality, customers and water source, while a diverse pricing should be pro-vided for different industries, also the water quota business among different consumption localities is encouraged so as to put the project benefit into full play. Generally, the water pricing mechanism should reflect the scarcity of water and treatment cost of wa-ter environment so as to improve the water saving sense, and guarantee the normal operation of water supply departments.%回顾了南水北调中线工程水价形成过程,指出了现行水价方案存在的问题。对真实水价形成机制进行了论述,认为制定水价应遵循公平负担、成本回收、合理利润、价格调整和水资源配置原则;同一水质、同类用户、不同水源的用水,应执行统一的水价;不同行业实行不同水价。鼓励受水区各省市间开展水量配额交易,最大限度发挥工程效益。供水水价既要反映水资源的稀缺程度和水环境治理成本,促进资源的节约使用和环境保护,提高全民节水意识,又要保证供水管理单位能够正常持续经营,具备自我积累、自我发展的能力。

  1. Diel activity patterns of juvenile late fall-run Chinook salmon with implications for operation of a gated water diversion in the Sacramento–San Joaquin River Delta

    Science.gov (United States)

    Plumb, John M.; Adams, Noah S.; Perry, Russell W.; Holbrook, Christopher; Romine, Jason G.; Blake, Aaron R.; Burau, Jon R.

    2016-01-01

    In the Sacramento-San Joaquin River Delta, California, tidal forces that reverse river flows increase the proportion of water and juvenile late fall-run Chinook salmon diverted into a network of channels that were constructed to support agriculture and human consumption. This area is known as the interior delta, and it has been associated with poor fish survival. Under the rationale that the fish will be diverted in proportion to the amount of water that is diverted, the Delta Cross Channel (DCC) has been prescriptively closed during the winter out-migration to reduce fish entrainment and mortality into the interior delta. The fish are thought to migrate mostly at night, and so daytime operation of the DCC may allow for water diversion that minimizes fish entrainment and mortality. To assess this, the DCC gate was experimentally opened and closed while we released 2983 of the fish with acoustic transmitters upstream of the DCC to monitor their arrival and entrainment into the DCC. We used logistic regression to model night-time arrival and entrainment probabilities with covariates that included the proportion of each diel period with upstream flow, flow, rate of change in flow and water temperature. The proportion of time with upstream flow was the most important driver of night-time arrival probability, yet river flow had the largest effect on fish entrainment into the DCC. Modelling results suggest opening the DCC during daytime while keeping the DCC closed during night-time may allow for water diversion that minimizes fish entrainment into the interior delta.

  2. Invertebrate diversity in southern California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This shapefile displays mean invertebrate diversity within 5 minute grid cells. The Shannon Index of diversity was calculated from Southern California Coastal Water...

  3. Cryptosporidiosis in Haiti: surprisingly low level of species diversity revealed by molecular characterization of Cryptosporidium oocysts from surface water and groundwater

    Science.gov (United States)

    Damiani, Céline; Balthazard-Accou, Ketty; Clervil, Elmyre; Diallo, Aïssata; Da Costa, Cécilia; Emmanuel, Evens; Totet, Anne; Agnamey, Patrice

    2013-01-01

    The protozoan parasite Cryptosporidium sp. has emerged as one of the most important water contaminants, causing waterborne outbreaks of diarrhoeal diseases worldwide. In Haiti, cryptosporidiosis is a frequent cause of diarrhoea in children under the age of five years, HIV-infected individuals, and people living in low socioeconomic conditions, mainly due to the consumption of water or food polluted by Cryptosporidium oocysts. The aim of this study was to detect and identify Cryptosporidium oocysts present in 12 water samples collected in Port-au-Prince and 4 water samples collected in Cap Haïtien. Initial detection consisted of immunomagnetic separation – immunofluorescence assay (IMS-IFA), which was confirmed by nested PCR, targeting the most polymorphic region of the 18S rRNA gene in 15/16 samples. Genotyping was performed by PCR-restriction fragment length polymorphism (RFLP) analysis and DNA sequencing. Under our working conditions, neither nested PCR-RFLP nor direct DNA sequencing revealed the expected species diversity, as only Cryptosporidium parvum was identified in the water samples studied. This study highlights the difficulty of detecting mixed populations of Cryptosporidium species in environmental samples. PMID:24252814

  4. Quantitative trait loci associated with natural diversity in water-use efficiency and response to soil drying in Brachypodium distachyon.

    Science.gov (United States)

    Des Marais, David L; Razzaque, Samsad; Hernandez, Kyle M; Garvin, David F; Juenger, Thomas E

    2016-10-01

    All plants must optimize their growth with finite resources. Water use efficiency (WUE) measures the relationship between biomass acquisition and transpired water. In the present study, we performed two experiments to understand the genetic basis of WUE and other parameters of plant-water interaction under control and water-limited conditions. Our study used two inbred natural accessions of Brachypodium distachyon, a model grass species with close phylogenetic affinity to temperate forage and cereal crops. First, we identify the soil water content which causes a reduction in leaf relative water content and an increase in WUE. Second, we present results from a large phenotyping experiment utilizing a recombinant inbred line mapping population derived from these same two natural accessions. We identify QTLs associated with environmentally-insensitive genetic variation in WUE, including a pair of epistatically interacting loci. We also identify QTLs associated with constitutive differences in biomass and a QTL describing an environmentally-sensitive difference in leaf carbon content. Finally, we present a new linkage map for this mapping population based on new SNP markers as well as updated genomic positions for previously described markers. Our studies provide an initial characterization of plant-water relations in B. distachyon and identify candidate genomic regions involved in WUE.

  5. Sorption and Desorption of Phenanthrene to Black Carbon on Crop Soil from the South-North Water Diversion Project in China

    Directory of Open Access Journals (Sweden)

    Rong Hao

    2014-07-01

    Full Text Available The water quality of South-North Water Diversion Project (SNWDP has attracted more and more attention. Polycyclic Aromatic Hydrocarbons (PAHs in soils strongly sorb to black carbon. In this study, adsorption and desorption characteristics and isotherm of phenanthrene to black carbon in SNWDP crop soils were studied extensively. The results showed that the sorption and desorption of phenanthrene to black carbon were nonlinear. Freundlich model could fit the sorption and desorption data of BC well. Meantime, desorption process exhibited varied apparent sorption-desorption hysteresis. It can be inferred that BC of crop soils in SNWDP plays a significant role in reducing the bioavailability and toxicity of phenanthrene through sorption capacity and desorption hysteresis.

  6. Microbial Diversity and Its Relationship to Physicochemical Characteristics of the Water in Two Extreme Acidic Pit Lakes from the Iberian Pyrite Belt (SW Spain.

    Directory of Open Access Journals (Sweden)

    Esther Santofimia

    Full Text Available The Iberian Pyrite Belt (IPB hosts one of the world's largest accumulations of acidic mine wastes and pit lakes. The mineralogical and textural characteristics of the IPB ores have favored the oxidation and dissolution of metallic sulfides, mainly pyrite, and the subsequent formation of acidic mining drainages. This work reports the physical properties, hydrogeochemical characteristics, and microbial diversity of two pit lakes located in the IPB. Both pit lakes are acidic and showed high concentrations of sulfate and dissolved metals. Concentrations of sulfate and heavy metals were higher in the Nuestra Señora del Carmen lake (NSC by one order of magnitude than in the Concepción (CN lake. The hydrochemical characteristics of NSC were typical of acid mine waters and can be compared with other acidic environments. When compared to other IPB acidic pit lakes, the superficial water of CN is more diluted than that of any of the others due, probably, to the strong influence of runoff water. Both pit lakes showed chemical and thermal stratification with well defined chemoclines. One particular characteristic of NSC is that it has developed a chemocline very close to the surface (2 m depth. Microbial community composition of the water column was analyzed by 16S and 18S rRNA gene cloning and sequencing. The microorganisms detected in NSC were characteristic of acid mine drainage (AMD, including iron oxidizing bacteria (Leptospirillum, Acidithiobacillus ferrooxidans and facultative iron reducing bacteria and archaea (Acidithiobacillus ferrooxidans, Acidiphilium, Actinobacteria, Acidimicrobiales, Ferroplasma detected in the bottom layer. Diversity in CN was higher than in NSC. Microorganisms known from AMD systems (Acidiphilium, Acidobacteria and Ferrovum and microorganisms never reported from AMD systems were identified. Taking into consideration the hydrochemical characteristics of these pit lakes and the spatial distribution of the identified

  7. Diversity of Flavobacterium psychrophilum and the potential use of its phages for protection against bacterial cold water disease in salmonids

    DEFF Research Database (Denmark)

    Castillo, D.; Higuera, G.; Villa, M.

    2012-01-01

    Flavobacterium psychrophilum causes rainbow trout fry syndrome (RTFS) and cold water disease (CWD) in salmonid aquaculture. We report characterization of F. psychrophilum strains and their bacteriophages isolated in Chilean salmonid aquaculture. Results suggest that under laboratory conditions ph...

  8. Distribution, abundance and diversity of phytoplankton in the inshore waters of Nizampatnam, South East coast of India.

    Digital Repository Service at National Institute of Oceanography (India)

    Pandiyarajan, R.S.; Shenai-Tirodkar, P; Ayajuddin, M.; Ansari, Z.A.

    Distribution, abundance and species assemblages of Phytoplankton were studied from inshore waters of Nizampatnam, South East coast of India in March 2007. Significant spatial variations in temperature, pH, salinity, dissolved oxygen (DO), nitrites...

  9. TAXONOMIC DIVERSITY AND THE ROLE OF ALGAEFLORA FOR BIOLOGICAL DEPURATION OF WATERS FROM RIVER COGÂLNIC (R. MOLDOVA

    Directory of Open Access Journals (Sweden)

    SALARU VICTOR

    2008-11-01

    Full Text Available During 2004-2005 there were performed studies regarding the taxonomic structure of the algaeflora in river Cogâlnic in order to point out the role of the algae during the process of water quality improvement and the role of the indicator of the most representative species. River Cogâlnic, or Cunduc, starts from nearby village Iurceni, district Nisporeni and flows into lake Sasac, and runs for a distance of 243 km. Decrease of the analyzed water quality from the river is caused by the sewerage waters from different sectors from town Hinceshti and Cimishlia that are directed into the river without any depuration. We've studied about 118 samples in which we've discovered about 382 species and intraspecific taxonomic units of algae of the following types: Cyanophyta -73, Euglenophyta-75, Chlorophyta-111, Xantophyta-3, Bacillariophyta-118 and Chrysophyta-2. Mass development of the euglena within Colgalnic river, among which are the following types of species Euglena-26, Trachelomonas-14 and Phacus-13, demonstrate a high level of trophicity in water. Among the chloride algae predominate the following species Scenedesmus-21, and from cyanophyta species predominates Oscillatoria-23. The high taxonomic level of the bacillariophyta algae is determined by species as Navicula-27, Nitzschia-24 and Surirella-16. Most of species refer to categories β and β-α , demonstrating a high level of water pollution. This fact speaks about the high concentration of nitrogen and phosphor compounds in water. It was demonstrated that as far as we go from the places were the sewerage waters flow into the river, the excessive quantities of biological elements decrease clearly. Also, go down the quantity of bicarbonates and oxidizers. Numeric growth of the algae is nothing else but a positive role for water depuration.

  10. A phylogenetic perspective on diversity of Galatheoidea (Munida, Munidopsis) from cold-water coral and cold seep communities in the western North Atlantic Ocean

    Science.gov (United States)

    Coykendall, Dolly K.; Nizinski, Martha S.; Morrison, Cheryl

    2016-01-01

    Squat lobsters (Galatheoidea and Chirostyloidea), a diverse group of decapod crustaceans, are ubiquitous members of the deep-sea fauna. Within Galatheoidea, the genera Munida and Munidopsis are the most diverse, but accurate estimates of biodiversity are difficult due to morphological complexity and cryptic diversity. Four species of Munida and nine species of Munidopsis from cold-water coral (CWC) and cold seep communities in the northwestern Atlantic Ocean (NWA) and the Gulf of Mexico (GOM) were collected over eleven years and fifteen research cruises in order to assess faunal associations and estimate squat lobster biodiversity. Identification of the majority of specimens was determined morphologically. Mitochondrial COI sequence data, obtained from material collected during these research cruises, was supplemented with published sequences of congeners from other regions. The phylogenetic analysis of Munida supports three of the four NWA and GOM species (M. microphthalma, M. sanctipauli, and M. valida) as closely related taxa. The fourth species, Munida iris, is basal to most other species of Munida, and is closely related to M. rutllanti, a species found in the northeastern Atlantic Ocean (NEA). The majority of the nine species of Munidopsis included in our analyses were collected from chemosynthetic cold seep sites from the GOM. While seep taxa were scattered throughout the phylogenetic tree, four of these species (Munidopsis livida, M. similis, M. bermudezi, and M. species A) from the NWA and the GOM were part of a large eighteen-species clade that included species collected from Pacific Ocean chemosynthetic habitats, such as hydrothermal vents and whale falls. Shinkaia crosnieri was the sister taxon to the chemosynthetic clade, and M. livida was the most basal member of this clade. Munidopsis sp. B, an undescribed species with representative individuals collected from two GOM chemosynthetic sites, exhibited the largest genetic distance from other northern

  11. A phylogenetic perspective on diversity of Galatheoidea (Munida, Munidopsis) from cold-water coral and cold seep communities in the western North Atlantic Ocean

    Science.gov (United States)

    Katharine Coykendall, D.; Nizinski, Martha S.; Morrison, Cheryl L.

    2017-03-01

    Squat lobsters (Galatheoidea and Chirostyloidea), a diverse group of decapod crustaceans, are ubiquitous members of the deep-sea fauna. Within Galatheoidea, the genera Munida and Munidopsis are the most diverse, but accurate estimates of biodiversity are difficult due to morphological complexity and cryptic diversity. Four species of Munida and nine species of Munidopsis from cold-water coral (CWC) and cold seep communities in the northwestern Atlantic Ocean (NWA) and the Gulf of Mexico (GOM) were collected over eleven years and fifteen research cruises in order to assess faunal associations and estimate squat lobster biodiversity. Identification of the majority of specimens was determined morphologically. Mitochondrial COI sequence data, obtained from material collected during these research cruises, was supplemented with published sequences of congeners from other regions. The phylogenetic analysis of Munida supports three of the four NWA and GOM species (M. microphthalma, M. sanctipauli, and M. valida) as closely related taxa. The fourth species, Munida iris, is basal to most other species of Munida, and is closely related to M. rutllanti, a species found in the northeastern Atlantic Ocean (NEA). The majority of the nine species of Munidopsis included in our analyses were collected from chemosynthetic cold seep sites from the GOM. While seep taxa were scattered throughout the phylogenetic tree, four of these species (Munidopsis livida, M. similis, M. bermudezi, and M. species A) from the NWA and the GOM were part of a large eighteen-species clade that included species collected from Pacific Ocean chemosynthetic habitats, such as hydrothermal vents and whale falls. Shinkaia crosnieri was the sister taxon to the chemosynthetic clade, and M. livida was the most basal member of this clade. Munidopsis sp. B, an undescribed species with representative individuals collected from two GOM chemosynthetic sites, exhibited the largest genetic distance from other northern

  12. Water

    Science.gov (United States)

    ... www.girlshealth.gov/ Home Nutrition Nutrition basics Water Water Did you know that water makes up more ... to drink more water Other drinks How much water do you need? top Water is very important, ...

  13. Thresholds in soil response to water stress: intensity and duration of dry-wet cycles induce differential soil C and bacterial diversity dynamics

    Science.gov (United States)

    Kaisermann, Aurore; Nunan, Naoise; Maron, Pierre-Alain; Terrat, Sébastien; Lata, Jean-Christophe

    2013-04-01

    After the wetting of dry soils, a CO2 flush (known as the 'Birch effect') is often observed. Although the Birch effect can often result in large CO2 fluxes, the process is not sufficiently well understood to predict its intensity. In particular, the impact of dry-wet cycles on microbial communities is poorly understood, as are the consequences of the possible changes for soil functioning. Using microcosm-based experiments, we investigated different climate change scenarios, such as drying periods of different durations (with co-variation of drying intensity and drought duration) and different rainfall intensities. The effects of four dry-wet cycles on the (i) immediate intensity of the Birch effect, (ii) rate of return to basal C mineralisation (functional resilience), (iii) total amount of CO2 released during a 5-month incubation and (iv) the dynamics of bacterial diversity were determined. Bacterial diversity was measured by pyrosequencing. The CO2 flush increased as a function of drying intensity, drought duration and wetting intensity but was not affected by the number of dry-wet cycles. However, the functional resilience was slower after the first dry-wet cycle than subsequent cycles, suggesting an adaptation of the microbial communities to water-stress. However, this was not associated with a higher stability of bacterial community since the pyrosequencing data showed that drying decreased bacterial diversity after each dry-wet cycle, but only if a threshold of minimal moisture is exceeded. These modifications were permanent over the long term and suggest that the communities were characterised by functional redundancy. Moderate droughts had no effect on overall CO2 emissions but severe droughts led to a lower loss of soil C due to the absence of mineralisation during the longer periods of desiccation that was not compensated by over-mineralisation during Birch effect. The study highlighted moisture threshold beyond which it can be observed a Birch effect and

  14. Bacterial diversity of floor drain biofilms and drain waters in a Listeria monocytogenes contaminated food processing environment.

    Science.gov (United States)

    Dzieciol, Monika; Schornsteiner, Elisa; Muhterem-Uyar, Meryem; Stessl, Beatrix; Wagner, Martin; Schmitz-Esser, Stephan

    2016-04-16

    Sanitation protocols are applied on a daily basis in food processing facilities to prevent the risk of cross-contamination with spoilage organisms. Floor drain water serves along with product-associated samples (slicer dust, brine or cheese smear) as an important hygiene indicator in monitoring Listeria monocytogenes in food processing facilities. Microbial communities of floor drains are representative for each processing area and are influenced to a large degree by food residues, liquid effluents and washing water. The microbial communities of drain water are steadily changing, whereas drain biofilms provide more stable niches. Bacterial communities of four floor drains were characterized using 16S rRNA gene pyrosequencing to better understand the composition and exchange of drain water and drain biofilm communities. Furthermore, the L. monocytogenes contamination status of each floor drain was determined by applying cultivation-independent real-time PCR quantification and cultivation-dependent detection according to ISO11290-1. Pyrosequencing of 16S rRNA genes of drain water and drain biofilm bacterial communities yielded 50,611 reads, which were clustered into 641 operational taxonomic units (OTUs), affiliated to 16 phyla dominated by Proteobacteria, Firmicutes and Bacteroidetes. The most abundant OTUs represented either product- (Lactococcus lactis) or fermentation- and food spoilage-associated phylotypes (Pseudomonas mucidolens, Pseudomonas fragi, Leuconostoc citreum, and Acetobacter tropicalis). The microbial communities in DW and DB samples were distinct in each sample type and throughout the whole processing plant, indicating the presence of indigenous specific microbial communities in each processing compartment. The microbiota of drain biofilms was largely different from the microbiota of the drain water. A sampling approach based on drain water alone may thus only provide reliable information on planktonic bacterial cells but might not allow conclusions

  15. Modeling Water Temperature in the Yakima River, Washington, from Roza Diversion Dam to Prosser Dam, 2005-06

    Science.gov (United States)

    Voss, Frank D.; Curran, Christopher A.; Mastin, Mark C.

    2008-01-01

    A mechanistic water-temperature model was constructed by the U.S. Geological Survey for use by the Bureau of Reclamation for studying the effect of potential water management decisions on water temperature in the Yakima River between Roza and Prosser, Washington. Flow and water temperature data for model input were obtained from the Bureau of Reclamation Hydromet database and from measurements collected by the U.S. Geological Survey during field trips in autumn 2005. Shading data for the model were collected by the U.S. Geological Survey in autumn 2006. The model was calibrated with data collected from April 1 through October 31, 2005, and tested with data collected from April 1 through October 31, 2006. Sensitivity analysis results showed that for the parameters tested, daily maximum water temperature was most sensitive to changes in air temperature and solar radiation. Root mean squared error for the five sites used for model calibration ranged from 1.3 to 1.9 degrees Celsius (?C) and mean error ranged from ?1.3 to 1.6?C. The root mean squared error for the five sites used for testing simulation ranged from 1.6 to 2.2?C and mean error ranged from 0.1 to 1.3?C. The accuracy of the stream temperatures estimated by the model is limited by four errors (model error, data error, parameter error, and user error).

  16. 鹤城区舞水河原生动物多样性及水质状况初步调查%Preliminary Investigation on the Diversity of Protozoa and Water Quality in Wushui River

    Institute of Scientific and Technical Information of China (English)

    向孙军; 杨席宽

    2012-01-01

    The diversity of protozoa and water quality were investigated in Wushui River, which was located in Hecheng district of Huaihua City, Hunan province. The results showed 23 species protozoa, belonging to 14 genera and in 2 classes, indwelled in the river. The highest and lowest diversity of protozoa community were the water boby under Wushui No. 1 Bridge and the third group in Yinjia, respectively. And the content of ammonia nitrogen in the water, which was taken from main stream, accorded with class I

  17. 引水放流方式对太湖贡湖示范区水质的影响%Impact of Water Diversion Methods on Water Quality of the Demonstration Area in Gonghu Bay

    Institute of Scientific and Technical Information of China (English)

    杨阳; 钱新; 叶瑞; 高海龙; 刘喆

    2015-01-01

    A proportional physical model,in accordance with the demonstration area which locates in Gonghu Bay,Taihu Lake,was constructed to meet the demand of controlling both quality and quantity of water within that area for the state water special project.The effects of four diversion methods in the models would be studied in or-der to provide arguments for making decisions between diversion methods for the demonstration area.When con-ducting the study,the influences to the model′s flow field,assessed by measuring flow field data at five different cross sections,would be deemed as indicators for evaluating different diversion methods.Meanwhile,ink was cho-sen as a tracer and the spreading field changes of the tracer caused by different diversion methods would verify conclusions to the flow field.Therefore,an analysis could be conducted for the impact to water quality caused by the methods.The study provided a helpful reference for deciding the diversion method for the demonstration area.%基于国家水专项太湖贡湖湾示范区水质水量调控的需求,构建了示范区的等比例缩放实体模型。通过研究模型中4种不同调水方案的效果,为示范区调水技术的比较与选择提供决策依据。研究中,通过测定模型中5个断面的流场数据,判断引水方式对模型流场的影响,以此评价不同调水方案效果。同时以墨汁作为示踪剂,通过不同引水放流方式下示踪剂的扩散场变化,验证不同断面流速测定对整个区域流场判断的准确性,从而分析引水放流方式对水质的影响。

  18. Presence, distribution, and diversity of iron-oxidizing bacteria at a landfill leachate-impacted groundwater surface water interface

    DEFF Research Database (Denmark)

    Yu, R.; Gan, P.; Mackay, A.A.;

    2010-01-01

    We examined the presence of iron-oxidizing bacteria (IOB) at a groundwater surface water interface (GSI) impacted by reduced groundwater originating as leachate from an upgradient landfill. IOB enrichments and quantifications were obtained, at high vertical resolution, by an iron/oxygen opposing...... gradient cultivation method. The depth-resolved soil distribution profiles of water content, Fe2+, and total Fe indicated sharp gradients within the top 10 cm sediments of the GSI, where the IOB density was the highest. In addition, the vertical distribution of iron-reducing bacteria at the same sampling...

  19. Exploring the genetic variability in water use efficiency: Evaluation of inter and intra cultivar genetic diversity in grapevines.

    Science.gov (United States)

    Tortosa, Ignacio; Escalona, José Mariano; Bota, Josefina; Tomás, Magdalena; Hernández, Esther; Escudero, Enrique García; Medrano, Hipólito

    2016-10-01

    Genetic improvement of crop Water Use Efficiency (WUE) is a general goal because the increasing water scarcity and the trend to a more sustainable agriculture. For grapevines, this subject is relevant and need an urgent response because their wide distribution in semi-arid areas. New cultivars are difficult to introduce in viticulture due to the narrow dependency of consumer appreciation often linked to a certain particular wine taste. Clones of reputed cultivars would presumably be more accepted but little is known on the intra-cultivar genetic variability of the WUE. The present work compares, on the basis of two field assays, the variability of intrinsic water use efficiency (WUEi) in a large collection of cultivars in contrast with a collection of clones of Tempranillo cultivar. The results show that clonal variability of WUEi was around 80% of the inter-cultivar, thus providing a first assessment on the opportunity for clonal selection by WUE. Plotting the WUEi data against stem water potential or stomatal conductance it was possible to identify cultivars and clones out of the confidence intervals of this linear regression thus with significantly higher and lower WUEi values. The present results contribute to open the expectative for a genetic improvement of grapevine WUE. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  20. ENVIRONMENTAL ASSESSMENT THE COASTAL AQUATORY OF KUIALNIK ESTUARY: MICROPHYTES, ZOOBENTHOS, DIVERSITY OF MICROBIOTA IN THE WATER AND PELOIDS

    Directory of Open Access Journals (Sweden)

    Polukarova L. A.

    2012-11-01

    Full Text Available We determined the concentration of macro- and microelements, such as: sodium, potassium, calcium, phosphorus, magnesium, iron, chlorides. We have also measured the concentration of hydrogen ions (pH and nitrogen of urea in samples of water and peloids which were taken from different places of Kuialnik estuary including territories around of such villages: Kotovka, Iliinka, Kovalevka, Novo Kovalevka, Belyayevsky district of Odessa region and such villages as: Korsuntsev, Krasnosilka, Kominternivskiy district of Odessa region.It was found that concentration of sodium and chlorides was high and increased from southern area to the northern part of Kuialnik estuary where volume of water is lesser. Hydrochemical investigation showed that concentration of macro- and microelements in the deep soils (peloids was lesser than in water samples and soils taken from the bottom of estuary. Investigation of tissue homogenates of brine shrimp (Artemia salina showed high enzyme activity of lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, alkaline phosphatase. The same biochemical parameters tested in biomass of blue-green algae (cyanoprokaryota, unicellular algae Microcystis sp. where high activity of alkaline phosphatase and high concentration of calcium, potassium and iron were registered. We studied the following microbiota: ferro-oxidizing bacteria (destructors of iron, manganese-oxidizing bacteria (destructors of manganese, sulfate-reducing bacteria, mycobacterium, thiobacteria and representatives from some other microbial groups in the water and peloid samples. Such integrated environmental investigation allowed to assess the environmental situation in different plots of the Kuialnik estuary more properly and complete.

  1. Sink or Swim: Navigating the Perilous Waters of Promotion and Tenure--What's Diversity Got to Do with It?

    Science.gov (United States)

    Knight, Wanda B.

    2010-01-01

    The "sink-or-swim" ideology is pervasive in the United States society. At research universities, for example, promotion and tenure are institutional waters in which faculty are forced to sink or swim with respect to publishing. Either they publish ("swim") or they perish ("sink"). In throwing faculty overboard, institutions assume that those who…

  2. Sink or Swim: Navigating the Perilous Waters of Promotion and Tenure--What's Diversity Got to Do with It?

    Science.gov (United States)

    Knight, Wanda B.

    2010-01-01

    The "sink-or-swim" ideology is pervasive in the United States society. At research universities, for example, promotion and tenure are institutional waters in which faculty are forced to sink or swim with respect to publishing. Either they publish ("swim") or they perish ("sink"). In throwing faculty overboard,…

  3. Molecular epidemiology and phylogenetic analysis of diverse bovine astroviruses associated with diarrhea in cattle and water buffalo calves in China.

    Science.gov (United States)

    Alfred, Niyokwishimira; Liu, Huan; Li, Mu Lan; Hong, Shao Feng; Tang, Hai Bo; Wei, Zu Zhang; Chen, Ying; Li, Fa Kai; Zhong, Yi Zhi; Huang, Wei Jian

    2015-06-01

    Astroviruses are the principal causative agents of gastroenteritis in humans and have been associated with diarrhea in other mammals as well as birds. However, astroviral infection of animals had been poorly studied. In the present study, 211 rectal swabs collected from cattle and water buffalo calves with mild to severe diarrhea were tested for bovine astrovirus (BAstV) by RT-PCR. Results: 92/211 (43.6%) samples were positive for BAstV, at a rate of 46.10% (71/154) in cattle and 36.84% (21/57) in water buffalo. Phylogenetic analysis based on the partial and full-length of 25 ORF2 amino acid sequences obtained in this study classified the Guangxi BAstVs isolates into five subgroups under the genus of Mamastrovirus, genotype MAstV33, which suggested that the water buffalo was a new host of this genogroup that previously included only cattle and roe deer. Despite the origin of the host, the Guangxi BAstV isolates were closely related to the BAstV Hong Kong isolates (B18/HK and B76-2/HK), but highly divergent from the BAstV NeuroS1 isolate previously associated with neurologic disease in cattle in the U.S.A. Nucleotide sequence-based characterization of the ORF1b/ORF2 junction and corresponding overlapping regions showed distinctive properties, which may be common to BAstVs. Our results suggested that cattle and water buffalo are prone to infection of closely related astroviruses, which probably evolved from the same ancestor. The current study described astroviruses in water buffalo for the first time and is thus far among the largest epidemiological investigations of BAstV infection in cattle conducted in China.

  4. Geochemistry and microbial diversity of cave waters in the gypsum karst aquifers of Emilia Romagna region, Italy.

    Science.gov (United States)

    D'Angeli, Ilenia M; Serrazanetti, Diana I; Montanari, Chiara; Vannini, Lucia; Gardini, Fausto; De Waele, Jo

    2017-11-15

    Fifty-seven control points of waters (sinking streams, rivers in caves, and resurgences) hosted in gypsum karst areas in Emilia Romagna region (N-Italy) were sampled in the framework of a Project LIFE+08NAT/IT/000369 "Gypsum" in the period 2010-2014. The microbiology and chemistry of these waters have been analyzed to evaluate the impact of human activities or natural factors, in the gypsum karst systems. Waters have been analyzed for major chemistry (Ca, Mg, Na, K, SO4, HCO3, Cl, NO3) and some minor constituents (F, Br, NH4 and PO4), measuring pH, electric conductivity (EC), total dissolved solids (TDS) and temperature (T) in situ. The same samples have been analyzed with traditional microbiology techniques focused on total microbial count and on fecal microbiota, as index of human and/or animal contamination, and molecular biology techniques (sequencing of 16S rRNA segment and PCR-DGGE), focused on the characterization of microbial populations in the different sampling sites and determination of their variations and/or changes during the five years of the project. As expected, waters tend to be increasingly mineralized from sinking streams to resurgences, with only local and temporarily high contents in nitrates and ammonium, often related to the presence of bat colonies. PCR-DGGE revealed ecological changes, in terms of microbial populations present in the bulk water samples, in different sampling sites within the same cave. Although the impact of fecal microorganisms only rarely exceeded 2 log UFC/ml, the results evidenced fluctuations of these microorganisms mainly correlated to the season and to the biological activity of bats. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. Construction of diverse supramolecular assemblies of dimetal subunits differing in coordinated water molecules via strong hydrogen bonding interactions: Synthesis, crystal structures and spectroscopic properties

    Indian Academy of Sciences (India)

    Sadhika Khullar; Sanjay K Mandal

    2014-09-01

    Three new supramolecular assemblies (constructed through strong hydrogen bonding) of [Co2(bpta)2(adc)(H2O)4](ClO4)2.2H2O (1), [Cu2(bpta)2(fum)(H2O)2](ClO4)2 (2) and [Cu2(bpta)2(tdc)(H2O) (ClO4)](ClO4).3H2O (3), which are synthesised by one pot self-assembly of the metal salt, bpta ligand and the corresponding dicarboxylate under the same reaction conditions, are reported (where adc = acetylene dicarboxylate, fum = fumarate, tdc = 2,5-thiophenedicarboxylate and bpta = N,N'-bis(2-pyridylmethyl)-tertbutylamine). These compounds have varying degrees of coordinatedwater molecules per dimetal subunits (four for 1, two for 2 and one for 3, respectively). Furthermore, the orientation of the coordinated water molecules in 1 and 2, with respect to the mono (carboxylato)-bridged dimetal subunit, is different (cis and trans, respectively). On the other hand, there is a coordinated perchlorate ion in 3 making the two metal centers inequivalent. Unlike 1 and 3, there are no lattice water molecules in 2. This difference in the dimetal subunit in 1-3 and the presence or absence of the lattice water molecules are the keys to forming the diverse supramolecular assemblies. In 1 and 3, the involvement of lattice water molecules in the construction of such assemblies is distinctly different. In case of 2, the formation of supramolecular assembly depends on the coordinated water molecule (trans to each other) and thus a ladder shaped supramolecular assembly is the result. The strength of hydrogen bonding observed in the networks of 1-3 is indicated in the O…O distances (2.596 Å to 3.160 Å) and the OH…O angles 124° to 176°. All are characterised by elemental analysis, FTIR spectroscopy and single crystal X-ray diffraction studies.

  6. Fish diversity in the Río de la Plata and adjacent waters: an overview of environmental influences on its spatial and temporal structure.

    Science.gov (United States)

    Jaureguizar, A J; Solari, A; Cortés, F; Milessi, A C; Militelli, M I; Camiolo, M D; Luz Clara, M; García, M

    2016-07-01

    The fish diversity and the main environmental factors affecting the spatial distribution of species, life history stages and community structure in the Río de la Plata (RdP) and adjacent waters are reviewed and analysed, with emphasis on the functional guild classification. The functional guild classification indicated that most species in the RdP were marine stragglers, zoobenthivores and oviparous species, although the biomass was dominated by estuarine species. Salinity had a stronger influence than temperature on the spatial pattern for all life stages, shallower and fresher waters are the preferred habitats of neonates and juveniles. During the breeding season (spring-summer), adults showed an intrusion into the inner part of RdP or to its adjacent nearshore waters from the offshore waters for spawning or mating, respectively. Variations in river discharge and wind patterns greatly affected the spatial extent of estuarine water, which ultimately influenced the domain of the main life-history stages (juveniles or adults) for both marine and estuarine fishes, as well as species and fish assemblage composition. The strong environmental gradient restricts some species and life-history stages to a particular section and defines three main fish assemblage areas. The composition of the fish assemblage is indicative of the recruitment of freshwater and marine species to the estuary in opposite ways, determined by the vertical stratification. Seasonal changes in the species composition were related to migration as a result of salinity and temperature variations and reproductive migrations to spawning and mating areas. This overview reveals that the RdP is under environmental variations that are likely to produce modifications to fish distribution and abundance that affect its fisheries. This context plus fish stock declines and changes in exploitation patterns could amplify the magnitude of the variations in the fisheries resources availability and affect the

  7. 基于取淡与流量控制的压咸调度方案研究%Pearl River Water Diversion Research Based on Drinking Water Supply Target and Flow Control

    Institute of Scientific and Technical Information of China (English)

    刘斌; 刘丽诗; 吴炜; 闻平; 黄宇铭

    2013-01-01

    Pearl River Delta is characterized by the staggered distribution of rivers network and estuarine system,which is different from the other estuaries of the world.The salty water intrusion in this area is also different as the complex hydrodynamic system.At the same time,Pearl River Delta has a large population and active economic activities,the population affected by salty water intrusion is over 10 million,and the affected daily water supply is over 10million m3.Thus,Pearl River Water Resources Commission of MWR has implemented water diversion for 8 years since 2005,the flow for repelling salty water intrusion can not be less than 1 800m3/s at the Wuzhou station.Based on the relationship between the salty tide and runoff,this paper made an analysis and put forward a new water diversion scheme based on the drinking water supply target and flow controlling.%珠江三角洲素有“三江汇流、八门出海”之称,河网、河口系统之复杂在世界上首屈一指,咸潮活动也因复杂的水动力系统表现出异于世界其他河口的特点.同时,珠江三角洲人口众多、经济活动活跃,受咸潮影响人口超过1 000万人、取水规模超过1 000×104m3/d.为此,珠江防总从2005年起已连续8次实施了水量调度,提出了梧州压咸流量不低于1 800 m3/s的单一控制指标,保障了供水安全.在8次水量调度的基础上,根据咸潮与径流、潮汐的响应关系,分3个流量级提出了基于平岗泵站和联石湾水闸取淡目标的西江+北江压咸补淡调度方案.

  8. Diversity, distribution and antibiotic resistance of Enterococcus spp. recovered from tomatoes, leaves, water and soil on U.S. Mid-Atlantic farms.

    Science.gov (United States)

    Micallef, Shirley A; Goldstein, Rachel E Rosenberg; George, Ashish; Ewing, Laura; Tall, Ben D; Boyer, Marc S; Joseph, Sam W; Sapkota, Amy R

    2013-12-01

    Antibiotic-resistant enterococci are important opportunistic pathogens and have been recovered from retail tomatoes. However, it is unclear where and how tomatoes are contaminated along the farm-to-fork continuum. Specifically, the degree of pre-harvest contamination with enterococci is unknown. We evaluated the prevalence, diversity and antimicrobial susceptibilities of enterococci collected from tomato farms in the Mid-Atlantic United States. Tomatoes, leaves, groundwater, pond water, irrigation ditch water, and soil were sampled and tested for enterococci using standard methods. Antimicrobial susceptibility testing was performed using the Sensititre microbroth dilution system. Enterococcus faecalis isolates were characterized using amplified fragment length polymorphism to assess dispersal potential. Enterococci (n = 307) occurred in all habitats and colonization of tomatoes was common. Seven species were identified: Enterococcus casseliflavus, E. faecalis, Enterococcus gallinarum, Enterococcus faecium, Enterococcus avis, Enterococcus hirae and Enterococcus raffinosus. E. casseliflavus predominated in soil and on tomatoes and leaves, and E. faecalis predominated in pond water. On plants, distance from the ground influenced presence of enterococci. E. faecalis from samples within a farm were more closely related than those from samples between farms. Resistance to rifampicin, quinupristin/dalfopristin, ciprofloxacin and levofloxacin was prevalent. Consumption of raw tomatoes as a potential exposure risk for antibiotic-resistant Enterococcus spp. deserves further attention.

  9. Evidence-based modelling of diverse plant water use strategies on stomatal and non-stomatal components under drought

    Science.gov (United States)

    zhou, S.; Prentice, C.; Medlyn, B. E.; Sabaté, S.

    2013-12-01

    Models disagree on how to represent effects of drought stress on plant gas exchange. Some models assume drought stress affects the marginal water use efficiency of plants (marginal WUE; i.e. the change in photosynthesis per unit of change in transpiration) whereas others assume drought stress acts directly on photosynthetic capacity. It is not clear whether either of these approaches is sufficient to capture the drought response, or whether the effect of drought varies among species and functional types. A collection of Eucalyptus and Quercus species derived from different hydro-climate habitats, in together with two European riparian species, were conducted with drought treatments respectively in Australia and Spain for three months. Measurements included net CO2 assimilation rate versus substomatal CO2 concentration (A-Ci) curves, fluorescence, and predawn leaf water potential at increasing levels of water stress. The correlations with quantitative plant traits of leaf, stomata, vessel, and wood density, leaf nitrogen content and 13C discrimination were also explored. We analysed the effect of drought effect on leaf gas exchange with a recently developed stomatal model that reconciles the empirical and optimal approaches on predicting optimal stomatal conductance. The model's single parameter g1 is a decreasing function of marginal WUE. The two genera showed consistence on the contrasting response patterns between species derived from mesic and arid habitats, which differed greatly in their estimated g1 values under moist conditions, and in the rate at which g1 declined with water stress. They also differed greatly in the predawn water potential at which apparent carboxylation capacity (apparent Vcmax) and mesophyll conductance (gm) declined most steeply, and in the steepness of this decline. Principal components analysis revealed a gradient in water relation strategies from sclerophyll species to malacophyll species. Malacophylls had higher g1, apparent Vcmax

  10. Structure and microbial diversity of biofilms on different pipe materials of a model drinking water distribution systems.

    Science.gov (United States)

    Rożej, Agnieszka; Cydzik-Kwiatkowska, Agnieszka; Kowalska, Beata; Kowalski, Dariusz

    2015-01-01

    The experiment was conducted in three model drinking water distribution systems (DWDSs) made of unplasticized polyvinyl chloride (PVC), silane cross-linked polyethylene (PEX) and high density polyethylene (HDPE) pipes to which tap water was introduced. After 2 years of system operation, microbial communities in the DWDSs were characterized with scanning electron microscopy, heterotrophic plate count, and denaturing gradient gel electrophoresis. The most extensive biofilms were found in HDPE pipes where bacteria were either attached to mineral deposits or immersed in exopolymers. On PEX surfaces, bacteria did not form large aggregates; however, they were present in the highest number (1.24 × 10(7) cells cm(-2)). PVC biofilm did not contain mineral deposits but was made of single cells with a high abundance of Pseudomonas aeruginosa, which can be harmful to human health. The members of Proteobacteria and Bacteroidetes were found in all biofilms and the water phase. Sphingomonadales and Methylophilaceae bacteria were found only in PEX samples, whereas Geothrix fermentans, which can reduce Fe(III), were identified only in PEX biofilm. The DNA sequences closely related to the members of Alphaproteobacteria were the most characteristic and intense amplicons detected in the HDPE biofilm.

  11. Diversity and endemism in cold waters of the South Atlantic: contrasting patterns in the plankton and the benthos

    Directory of Open Access Journals (Sweden)

    Demetrio Boltovskoy

    2005-12-01

    Full Text Available In total, ca. 7000 zooplanktonic species have been described for the World Ocean. This figure represents less than 4% of the total number of known marine organisms. Of the 7000 zooplanktonic species world-wide, some 60% are present in the South Atlantic; about one third of the latter have been recorded in its Subantarctic waters, and ca. 20% south of the Polar Front. When compared with those of benthic animals, these figures indicate that proportions of the overall inventories that are present in the cold waters are almost two times higher among the zooplankton. In agreement with this pattern, the proportions of Antarctic endemics in the benthos are very significantly higher than those in the plankton. For the water-column dwelling animals, the Polar Front boundary is more important than the Tropical-Subtropical limit, but almost equivalent to the Subtropical-Transitional limit, and weaker in biogeographic terms than the Transitional-Subantarctic boundary. Some of the implications of these dissimilarities, both for ecological theory and for resource allocation strategies, are discussed.

  12. Emigration Resettlement in the Water Source Project in Middle Route of the South-to-north Water Diversion Project%南水北调中线水源工程移民安置

    Institute of Scientific and Technical Information of China (English)

    李世荣; 李德刚

    2015-01-01

    阐述了南水北调中线工程,论证过程,移民安置的任务、规划、实施结果及评价。经终验委员会审议,南水北调丹江口水库大坝加高工程建设征地补偿和移民安置蓄水前终验评定为合格,能够满足丹江口水库大坝加高后蓄水的要求。%The emigration resettlement work in the water source project in middle route of the south-to-north water diver-sion project is introduced, including the mission, plan, implementation result and the final assessment.Based on the deliberation of the project acceptance committee, the emigration resettlement work is satisfying.

  13. Occurrence and diversity of integrons and beta-lactamase genes among ampicillin-resistant isolates from estuarine waters.

    Science.gov (United States)

    Henriques, Isabel S; Fonseca, Fátima; Alves, Artur; Saavedra, Maria José; Correia, António

    2006-12-01

    The aim of the present study was to assess the occurrence and molecular diversity of beta-lactamase genes and integrons among Gram-negative ampicillin-resistant bacteria from Ria de Aveiro. Ampicillin-resistant isolates were selected and subjected to genotyping using REP-PCR. Representatives from each REP pattern were affiliated with the following taxa by sequencing the 16S rRNA gene: Aeromonas caviae, A. hydrophila, A. media, A. molluscorum, A. veronii, A. salmonicida, Aeromonas sp., Pseudomonas putida, Pseudomonas sp., Escherichia coli, Escherichia sp., Shigella sonnei, Shigella sp., Klebsiella pneumoniae, K. oxytoca, Raoultella ornithinolytica, R. terrigena, R. planticola, Citrobacter freundii, Morganella morganii and Enterobacter sp. Isolates affiliated with genera Escherichia or Shigella were identified as Escherichia coli using phenotypic-based tests. PCR was used to assess beta-lactamase encoding sequences (bla(TEM), bla(SHV), bla(CARB), bla(CTX-M), bla(IMP), bla(VIM), bla(CphA/IMIS), bla(OXA-A), bla(OXA-B), bla(OXA-C)), class 1 and class 2 integrases, and integron variable regions. Sequence analysis of PCR products was performed. beta-Lactamase genes were detected in 77.8% of the Enterobacteriaceae and in 10.5% of the Aeromonas. The most frequently detected gene was bla(TEM), followed by bla(SHV,)bla(OXA-B), bla(CphA/IMIS) and bla(CARB). Retrieved sequences shared high homology with previously described beta-lactamases. The intI1 gene was present in 29.6% of the Enterobacteriaceae and in 21% of the Aeromonas isolates. The intI2 gene was present in 4 isolates. A total of 13 cassettes included in 12 different cassette arrays were identified. The most frequently found resistance gene cassettes were aadA variants. Previous investigations based on cultivation-independent approaches revealed higher molecular diversity among beta-lactamase-encoding sequences in this estuary. This fact reinforces the hypothesis that cultivation-dependent approaches may

  14. Characterization of bacterial diversity associated with calcareous deposits and drip-waters, and isolation of calcifying bacteria from two Colombian mines.

    Science.gov (United States)

    García G, Mariandrea; Márquez G, Marco Antonio; Moreno H, Claudia Ximena

    2016-01-01

    Bacterial carbonate precipitation has implications in geological processes and important biotechnological applications. Bacteria capable of precipitating carbonates have been isolated from different calcium carbonate deposits (speleothems) in caves, soil, freshwater and seawater around the world. However, the diversity of bacteria from calcareous deposits in Colombia, and their ability to precipitate carbonates, remains unknown. In this study, conventional microbiological methods and molecular tools, such as temporal temperature gradient electrophoresis (TTGE), were used to assess the composition of bacterial communities associated with carbonate deposits and drip-waters from two Colombian mines. A genetic analysis of these bacterial communities revealed a similar level of diversity, based on the number of bands detected using TTGE. The dominant phylogenetic affiliations of the bacteria, determined using 16S rRNA gene sequencing, were grouped into two phyla: Proteobacteria and Firmicutes. Within these phyla, seven genera were capable of precipitating calcium carbonates: Lysinibacillus, Bacillus, Strenotophomonas, Brevibacillus, Methylobacterium, Aeromicrobium and Acinetobacter. FTIR and SEM/EDX were used to analyze calcium carbonate crystals produced by isolated Acinetobacter gyllenbergii. The results showed that rhombohedral and angular calcite crystals with sizes of 90μm were precipitated. This research provides information regarding the presence of complex bacterial communities in secondary carbonate deposits from mines and their ability to precipitate calcium carbonate from calcareous deposits of Colombian mines.

  15. Research on the Construction of Project Critical Chain Model in South-to-North Water Diversion Project with Multi-Resource Constraints Based on Portfolio Technology

    Directory of Open Access Journals (Sweden)

    Jing-chun FENG

    2011-06-01

    Full Text Available Recently, the critical chain study has become the hot spot within the project management research field, so as the construction of it with multi-resource constraints become the new research subject. Referring to System Analysis Theory and Project Portfolio Theory, this paper discusses the creation of project portfolio based on project similarity, and definition of priority in multi-resource allocation based on quantitative analysis. Then according to the theory on critical chain construction, the author made relevant research and proposed the construction model with the multi-resource constraints, which to be applied to the critical chain construction of A-bid section in South-to-North Water Diversion Project. And necessary contrast analysis with the Comprehensive Treatment Construction Method and Aggressive Treatment Construction Method also has been made within this paper.

  16. Bacterial diversity in surface water of the Yellow Sea during and after a green alga tide in 2008

    Science.gov (United States)

    Guo, Cong; Li, Fuchao; Jiang, Peng; Liu, Zhaopu; Qin, Song

    2011-11-01

    From May to August 2008, a large "green tide", consisting of the alga Ulva ( Enteromorpha) prolifera, occurred in the Yellow Sea, China, affecting the local marine ecosystem and human activities. We investigated the influence of the green tide on the microbial community in the surface seawater, at four sites from July to August 2008, using bacterial 16S rRNA gene clone libraries. We sequenced 228 clones of unique patterns identified by restriction fragment length polymorphism (RFLP) techniques. The results show that 228 sequenced clones fell into six bacterial phyla: Proteobacteria, Bacteroidetes, Cyanobacteria, Verrucomicrobia, Actinobacteria, and Planctomycetes. Alphaproteobacteria (33%), Gammaproteobacteria (25%), Bacteroidetes (23%) and Cyanobacteria (9%) dominated the assemblage. Comparison between samples collected in July (during the tide) and those collected in August (after the tide) showed that, in the microbial community, diversities of Alphaproteobacteria and Cyanobacteria increased after the tide, while those of Gammaproteobacteria and Bacteroidetes decreased. These results indicate that the green tide influenced the growth of some bacteria, and provide information for further studies on the interactions and relationships between U. prolifera and the bacterial community. This study suggests that microbial community analysis is a good approach to monitoring green tides.

  17. Bacterial diversity in surface water of the Yellow Sea duringand after a green alga tide in 2008

    Institute of Scientific and Technical Information of China (English)

    GUO Cong; LI Fuchao; JIANG Peng; LIU Zhaopu; QIN Song

    2011-01-01

    From May to August 2008,a large "green tide",consisting of the alga Ulva (Enteromorpha) prolifera,occurred in the Yellow Sea,China,affecting the local marine ecosystem and human activities.We investigated the influence of the green tide on the microbial community in the surface seawater,at four sites from July to August 2008,using bacterial 16S rRNA gene clone libraries.We sequenced 228clones of unique patterns identified by restriction fragment length polymorphism (RFLP) techniques.The results show that 228 sequenced clones fell into six bacterial phyla:Proteobacteria,Bacteroidetes,Cyanobacteria,Verrucomicrobia,Actinobacteria,and Planctomycetes.Alphaproteobacteria (33%),Gammaproteobacteria (25%),Bacteroidetes (23%) and Cyanobacteria (9%) dominated the assemblage.Comparison between samples collected in July (during the tide) and those collected in August (after the tide) showed that,in the microbial community,diversities of Alphaproteobacteria and Cyanobacteria increased after the tide,while those of Gammaproteobacteria and Bacteroidetes decreased.These results indicate that the green tide influenced the growth of some bacteria,and provide information for further studies on the interactions and relationships between U.prolifera and the bacterial community.This study suggests that microbial community analysis is a good approach to monitoring green tides.

  18. 海水养殖水体硅藻的多样性与作用%Diversity of diatoms and its important role in marine aquaculture waters

    Institute of Scientific and Technical Information of China (English)

    高亚辉; 李雪松; 吴文忠

    2012-01-01

    Diatom is a main component of phytoplankton and benthic algae in marine aquaculture areas and is important food organisms of marine fish, shellfish and shrimps, which plays a very important ecological role in element cycle and energy flow in marine aquaculture waters. In the present paper, a review is made on the study progress focusing on the diatoms in the marine aquaculture waters including the following aspects: diatom species diversity, nano - diatom and its role, taxonomy of diatom, nutrition value of diatom cells as animal food. This review is made aiming on increasing our knowledge on diatom taxonomy, species diversity, and their relationship with aquaculture capacity and aquaculture environment changes.%硅藻是海水养殖水体浮游植物和底栖藻类中的最主要类群,也是鱼类、贝类和虾类的重要饵料生物,在养殖水体的物质循环和能量流动中起着极其重要的生态作用。本文对海水养殖水体硅藻的种类多样性、微型硅藻的分布与作用、硅藻的分类研究、硅藻的营养价值与饵料作用等进行了综述,为丰富硅藻的分类学和多样性研究、优化养殖环境、提高养殖动物生产力等提供参考资料。

  19. Abundance and diversity of bacteria in oxygen minimum drinking water reservoir sediments studied by quantitative PCR and pyrosequencing.

    Science.gov (United States)

    Zhang, Hai-han; Huang, Ting-lin; Chen, Sheng-nan; Yang, Xiao; Lv, Kai; Sekar, Raju

    2015-04-01

    Reservoir sediment is one of the most stressful environments for microorganisms due to periodically oxygen minimum conditions. In this study, the abundance and composition of bacteria associated with sediments from three drinking water reservoirs (Zhoucun, ZCR; Shibianyu, SBYR; and Jinpen, JPR) were investigated by quantitative polymerase chain reaction and 16S rRNA-based 454 pyrosequencing. The results of physico-chemical analysis of sediments showed that the organic matter and total nitrogen were significantly higher in ZCR as compared to JPR (P oxygen minimum and stressful freshwater environments.

  20. Time series monitoring of water quality and microalgal diversity in a tropical bay under intense anthropogenic interference (SW coast of the Bay of Bengal, India)

    Energy Technology Data Exchange (ETDEWEB)

    Shaik, Aziz ur Rahman [CSIR — National Institute of Oceanography, Regional Centre, 176 Lawson' s Bay Colony, Visakhapatnam, AP 530017 (India); Biswas, Haimanti, E-mail: haimanti.biswas@nio.org [CSIR — National Institute of Oceanography, Regional Centre, 176 Lawson' s Bay Colony, Visakhapatnam, AP 530017 (India); Reddy, N.P.C.; Srinivasa Rao, V. [CSIR — National Institute of Oceanography, Regional Centre, 176 Lawson' s Bay Colony, Visakhapatnam, AP 530017 (India); Bharathi, M.D. [Present address: ICMAM Project Directorate, 2nd Floor, NIOT Campus, Velacherry-Tambaram Main Road, Pallikkaranai, Chennai 600100 (India); Subbaiah, Ch.V. [CSIR — National Institute of Oceanography, Regional Centre, 176 Lawson' s Bay Colony, Visakhapatnam, AP 530017 (India)

    2015-11-15

    In recent decades, material fluxes to coastal waters from various land based anthropogenic activities have significantly been enhanced around the globe which can considerably impact the coastal water quality and ecosystem health. Hence, there is a critical need to understand the links between anthropogenic activities in watersheds and its health. Kakinada Bay is situated at the SW part of the Bay of Bengal, near to the second largest mangrove cover in India with several fertilizer industries along its bank and could be highly vulnerable to different types of pollutants. However, virtually, no data is available so far reporting its physicochemical status and microalgal diversity at this bay. In order to fill this gap, we conducted three time series observations at a fixed station during January, December and June 2012, at this bay measuring more than 15 physical, chemical and biological parameters in every 3 h over a period of 36 h in both surface (0 m) and subsurface (4.5 m) waters. Our results clearly depict a strong seasonality between three sampling months; however, any abnormal values of nutrients, biological oxygen demand or dissolved oxygen level was not observed. A Skeletonema costatum bloom was observed in December which was probably influenced by low saline, high turbid and high Si input through the river discharge. Otherwise, smaller diatoms like Thalassiosira decipiens, Thalassiothrix frauenfeldii, and Thalassionema nitzschioides dominated the bay. It is likely that the material loading can be high at the point sources due to intense anthropogenic activities, however, gets diluted with biological, chemical and physical processes in the offshore waters. - Highlights: • No signature of enormous nutrient loading was observed over the diel cycle • Dissolved oxygen and BOD concentrations did not show any exceptional trend • Diatoms dominated more than 90% of the total phytoplankton communities • A Skeletonema Costatum (a centric diatom) bloom was

  1. Ecological consequences of hydropower development in Central America: Impacts of small dams and water diversion on neotropical stream fish assemblages

    Science.gov (United States)

    Anderson, Elizabeth P.; Freeman, Mary C.; Pringle, C.M.

    2006-01-01

    Small dams for hydropower have caused widespread alteration of Central American rivers, yet much of recent development has gone undocumented by scientists and conservationists. We examined the ecological effects of a small hydropower plant (Dona Julia Hydroelectric Center) on two low-order streams (the Puerto Viejo River and Quebradon stream) draining a mountainous area of Costa Rica. Operation of the Dona Julia plant has dewatered these streams, reducing discharge to ~ 10% of average annual flow. This study compared fish assemblage composition and aquatic habitat upstream and downstream of diversion dams on two streams and along a ~ 4 km dewatered reach of the Puerto Viejo River in an attempt to evaluate current instream flow recommendations for regulated Costa Rican streams. Our results indicated that fish assemblages directly upstream and downstream of the dam on the third order Puerto Viejo River were dissimilar, suggesting that the small dam (fishes. Along the ~ 4 km dewatered reach of the Puerto Viejo River, species count increased with downstream distance from the dam. However, estimated species richness and overall fish abundance were not significantly correlated with downstream distance from the dam. Our results suggested that effects of stream dewatering may be most pronounced for a subset of species with more complex reproductive requirements, classified as equilibrium-type species based on their life-history. In the absence of changes to current operations, we expect that fish assemblages in the Puerto Viejo River will be increasingly dominated by opportunistic-type, colonizing fish species. Operations of many other small hydropower plants in Costa Rica and other parts of Central America mirror those of Doha Julia; the methods and results of this study may be applicable to some of those projects.

  2. Isolation and molecular characterization of potentially pathogenic Acanthamoeba genotypes from diverse water resources including household drinking water from Khyber Pakhtunkhwa, Pakistan.

    Science.gov (United States)

    Tanveer, Tania; Hameed, Abdul; Muazzam, Ambreen Gul; Jung, Suk-Yul; Gul, Asma; Matin, Abdul

    2013-08-01

    Acanthamoeba, an opportunistic protozoan pathogen, is ubiquitous in nature, and therefore plays a predatory role and helps control microbial communities in the ecosystem. These Acanthamoeba species are recognized as opportunistic human pathogens that may cause blinding keratitis and rare but fatal granulomatous encephalitis. To date, there is not a single report demonstrating Acanthamoeba isolation and identification from environmental sources in Pakistan, and that is the aim of this study. Acanthamoeba were identified by morphological characteristics of their cysts on non-nutrient agar plates seeded with Escherichia coli. Additionally, the polymerase chain reaction (PCR) was performed with genus-specific primers followed by direct sequencing of the PCR product for molecular identification. Furthermore, our PCR and sequencing results confirmed seven different pathogenic and nonpathogenic genotypes, including T2-T10, T4, T5, T7, T15, T16, and T17. To the best of our knowledge, we have identified and isolated Acanthamoeba sp., for the first time, from water resources of Khyber Pakhtunkhwa, Pakistan. There is an urgent need to address (1) the pathogenic potential of the identified genotypes and (2) explore other environmental sources from the country to examine the water quality and the current status of Acanthamoeba species in Pakistan, which may be a potential threat for public health across the country.

  3. Diversity of Norwegian sea slugs (Nudibranchia: new species to Norwegian coastal waters and new data on distribution of rare species

    Directory of Open Access Journals (Sweden)

    Jussi Evertsen

    2013-02-01

    Full Text Available A total of 5 nudibranch species are reported from the Norwegian coast for the first time (Doridoxa ingolfiana, Goniodoris castanea, Onchidoris sparsa, Eubranchus rupium and Proctonotus mucroniferus. In addition 10 species that can be considered rare in Norwegian waters are presented with new information (Lophodoris danielsseni, Onchidoris depressa, Palio nothus, Tritonia griegi, Tritonia lineata, Hero formosa, Janolus cristatus, Cumanotus beaumonti, Berghia norvegica and Calma glaucoides, in some cases with considerable changes to their distribution. These new results present an update to our previous extensive investigation of the nudibranch fauna of the Norwegian coast from 2005, which now totals 87 species. An increase in several new species to the Norwegian fauna and new records of rare species, some with considerable updates, in relatively few years results mainly from sampling effort and contributions by specialists on samples from poorly sampled areas.

  4. Long-term succession of structure and diversity of a biofilm formed in a model drinking water distribution system

    DEFF Research Database (Denmark)

    Martiny, A.C.; Jørgensen, T.M.; Albrechtsen, Hans-Jørgen

    2003-01-01

    In this study, we examined the long-term development of the overall structural morphology and community composition of a biofilm formed in a model drinking water distribution system with biofilms from 1 day to 3 years old. Visualization and subsequent quantification showed how the biofilm developed...... length polymorphisms showed a correlation between the population profile and the age of the sample, separating the samples into young (1 to 94 days) and old (571 to 1,093 days) biofilms, whereas a limited spatial variation in the biofilm was observed. A more detailed analysis with cloning and sequencing......% of the community by day 256, and which resulted in a reduction in the overall richness. After 500 days, the biofilm entered a stable population state, which was characterized by a greater richness of bacteria, including Nitrospira, Planctomyces, Acidobacterium, and Pseudomonas. The combination of different...

  5. Development of water facilities in the Santa Ana River Basin, California, 1810-1968: a compilation of historical notes derived from many sources describing ditch and canal companies, diversions, and water rights

    Science.gov (United States)

    Scott, M.B.

    1977-01-01

    This report traces by text, maps, and photographs, the development of the water supply in the Santa Ana River basin from its beginning in 1810 or 1811 to 1968. The value of the report lies in the fact that interpretation of the hydrologic systems in the basin requires knowledge of the concurrent state of development of the water supply, because that development has progressively altered the local regimen of both surface water and ground water. Most of the information for the earlier years was extracted and condensed from an investigation made by W. H. Hall, California State Engineer during the years 1878-87. Hall's study described irrigation development in southern California from its beginning through 1888. Information for the years following 1888 was obtained from the archives of the numerous water companies and water agencies in the Santa Ana River basin and from the various depositories of courthouse, county, and municipal records. The history of water-resources development in the Santa Ana River basin begins with the introduction of irrigation in the area by the Spanish, who settled in southern California in the latter part, of the 18th century. The first irrigation diversion from the Santa Ana River was made in 1810 or 1811 by Jose Antonio Yorba and Juan Pablo Peralta. Irrigation remained a localized practice during the Mexican-Californian, or rancho, period following the separation of Mexico from Spain in 1821. Rancho grantees principally raised cattle, horses, and sheep and irrigated only small· plots of feed grain for their livestock and fruit crops for household use. The breakup of the ranchos through sales to Americans, who were migrating to California in ever-increasing numbers following the acquisition of California by the United States in 1848, marked the beginning of a rapid increase in water use and the beginning of widespread irrigation. Many water companies and water agencies were organized to divert the surface flow of the Santa Ana River and

  6. Plankton diversity and water quality assessment of three freshwater lakes of Mandi (Himachal Pradesh, India) with special reference to planktonic indicators.

    Science.gov (United States)

    Thakur, R K; Jindal, R; Singh, Uday Bhan; Ahluwalia, A S

    2013-10-01

    The present study deals with the limnobiotic status of three selected lakes of Himachal Pradesh using physicochemical and biological parameters (especially phytoplankton and zooplankton) over a period of 2 years. One hundred forty-eight species belonging to nine groups of phytoplankton and 79 species belonging to five groups of zooplankton were identified from the lakes. Trophic level and the pollution status of the lakes were assessed upon the basis of Shannon diversity index (H'), species richness index (S), and physicochemical parameters. Plankton population size was correlated with biotic and abiotic parameters (pH, alkalinity, temperature, dissolved oxygen, transparency, phosphate, chloride, and nitrate). The present investigation revealed that the distribution of plankton species depended upon the physicochemical parameters of the environment. Based on water quality standards given by the Central Pollution Control Board, the water quality was between "A-B" at Prashar wetland, "C-D" at Kuntbhyog Lake, and "D-E" at Rewalsar Lake. The results from the present study indicated that the potential of planktons as bioindicators of trophic status is very high.

  7. Exploring the genetic diversity of shallow-water Agariciidae (Cnidaria: Anthozoa) from the Saudi Arabian Red Sea

    KAUST Repository

    Terraneo, Tullia I.

    2017-05-19

    Scleractinian corals ascribed to the family Agariciidae represent an important component of Red Sea coral reef fauna, though little genetic data are currently available for this group, and existing information shows polyphyly in the examined mesophotic taxa from the Pacific Ocean. In this work, we provide a first genetic survey of Agariciidae from the Saudi Arabian Red Sea, based on a collection of shallow-water material (<30 m) from the Gulf of Aqaba to the Farasan Islands. Two molecular markers were sequenced to infer morphospecies monophyly and relationships, the intergenic region between COI and 16S rRNA from mitochondrial DNA and the ribosomal ITS1 region from nuclear DNA. A total of 20 morphospecies were identified based on classical macromorphological characters. Six, namely Gardineroseris planulata, Pavona maldivensis, Pavona clavus, Pavona decussata, Leptoseris fragilis, and Leptoseris yabei, were resolved with both DNA loci. The molecular boundaries among the remaining 14 species remain unclear. Our results further confirm that the morphology-based taxonomy of most agariciid species is in disagreement with genetics. In order to disentangle the systematics of these taxa, the inclusion of more sampling locations, additional variable loci, and a micromophological approach are likely needed. Our genetic data represent a first step towards the comparison of biodiversity and connectivity between the Red Sea and the rest of the Indo-Pacific.

  8. Identity, Diversity and Diversity Management

    DEFF Research Database (Denmark)

    Holck, Lotte; Muhr, Sara Louise; Villeseche, Florence

    2016-01-01

    – The work can encourage policy makers, diversity and HR managers to question their own practices and assumptions leading to more theoretical informed diversity management practices. Originality/value – The theoretical connections between identity and diversity literature have so far not been reviewed...... systematically. The work foregrounds how important it is for diversity scholars to consider identity underpinnings of diversity research to help further develop the field within and beyond the three streams the authors discuss.......The purpose of this paper is to examine the relationship between the identity and diversity literatures and discuss how a better understanding of the theoretical connections between the two informs both diversity research and diversity management practices. Design/methodology/approach – Literature...

  9. 江苏南水北调工程运行管理浅析%Analysis about Operation and Management of Jiangsu South-to-North Water Diversion Project

    Institute of Scientific and Technical Information of China (English)

    荣迎春; 李松柏; 滕海波

    2012-01-01

    为适应南水北调东线一期工程全线通水需要,通过简要介绍江苏南水北调工程的概况与传统水利工程管理的特点,详细分析了南水北调东线江苏段工程采用直接管理、委托管理和协议管理的优缺点,对江苏南水北调工程前期建成工程运行管理经验作了系统总结,并与传统水利工程运行管理模式进行比较,探讨了前期建成工程运行管理中需要进一步完善的问题和措施,力求从理论和实践角度积极探索建立适应南水北调东线江苏段工程需要的运行管理模式,努力为推动江苏南水北调工程管理体制和运行机制的确立,从而保证江苏段工程全线建成通水,确保发挥工程设计效益作了有益的研究和思考.%In order to meet the water transmit requirement of the Eastern Route of the South-to-North Water Diversion Project, this article briefly describes the overview of the South-to-North Water Diversion Project in Jiangsu and the feature of traditional water conservancy project management The advantages and disadvantages of the direct management, entrusted management and agreement management which adopt by the South-to-North Water Diversion Project in Jiangsu have been detailed analyzed Operation and management experience of early South-to-North Water Diversion Project in Jiangsu were summarized and compared with traditional water conservancy project Further improvement of operation and management in early South-to-North Water Diversion Project in Jiangsu has been discussed Explore a suitable operation and management mode from theory and practice, to establish the project management system and operation mechanism of South-to-North Water Diversion Project in Jiangsu. Beneficial research has been done to meet the water transmit requirement and to produce project design efficiency.

  10. A study of subsurface regulation and storage of water after the South-to-North Water Diversion Project into Shandong%南水北调入鲁后地下调蓄研究

    Institute of Scientific and Technical Information of China (English)

    乔令海; 徐军祥; 张中祥; 乔云

    2012-01-01

    南水北调东线山东段输水干渠沿线分布有第四系松散岩类孔隙含水层组、碳酸盐岩类裂隙岩溶含水层组、碎屑岩类裂隙含水层组和岩浆岩变质岩类裂隙含水层组.前2个含水层组具有巨大的含水空间,可进行地表水、地下水联合调蓄.沿线共划分出地下可调蓄区段9个,其中调蓄能力较强、调蓄条件较好应优先考虑的区段有济宁、东阿、莱龙蓬、烟台、牟平区段,调蓄能力较强但调蓄条件较差、需要辅助引水工程的区段为济南、淄博、潍坊、青岛区段.经估算,沿线地下可调蓄总量为20.4756×lO8m3.%Along the main canal of the Eastern Route of Shandong section of the South-to-North Water Diversion Project occur aquifers of Quaternary unconsolidated sediments, fissured-karst aquifers of carbonate rocks, fissured aquifers of clastic rocks and cranny aquifers of magmatic rocks metamorphic rocks. The first two types of aquifers are of huge void for water storage and surface water and groundwater conjunctive regulation are carried out. Nine regulation and storage sections can be divided along the canal. Priority should be given to sections with strong storage capability and good storage conditions such as Jining, Dong'e, Yantai, Lai-Long-Peng and Muping sections. Ji'nan, Zibo, Weifang and Qingdao sections are of strong storage capacity but poor storage condition, and require auxiliary water diversion projects. The subsurface storage amount along the canal can be estimated as 20. 4756 × 108m3.

  11. Cultural diversity

    OpenAIRE

    Raghavan, Raghu

    2011-01-01

    The concept of cultural diversity has emerged as an influential one having impact on multiple policy and legal instruments especially following the adoption of the UNESCO Convention on the Protection and Promotion of the Diversity of Cultural Expressions in 2005. The discussions on its appropriate implementation are however profoundly fragmented and often laden with political considerations. The present brief paper offers some thoughts on the meaning of cultural diversity and its implementati...

  12. Spatial variability of particle-attached and free-living bacterial diversity in surface waters from the Mackenzie River to the Beaufort Sea (Canadian Arctic)

    Science.gov (United States)

    Ortega-Retuerta, E.; Joux, F.; Jeffrey, W. H.; Ghiglione, J. F.

    2013-04-01

    We explored the patterns of total and active bacterial community structure in a gradient covering surface waters from the Mackenzie River to the coastal Beaufort Sea in the Canadian Arctic Ocean, with a particular focus on free-living (FL) vs. particle-attached (PA) communities. Capillary electrophoresis-single-strand conformation polymorphism (CE-SSCP) showed significant differences when comparing river, coast and open sea bacterial community structures. In contrast to the river and coastal waters, total (16S rDNA-based) and active (16S rRNA-based) communities in the open sea samples were not significantly different, suggesting that most present bacterial groups were equally active in this area. Additionally, we observed significant differences between PA and FL bacterial community structure in the open sea, but similar structure in the two fractions for coastal and river samples. Direct multivariate statistical analyses showed that total community structure was mainly driven by salinity (a proxy of dissolved organic carbon and chromophoric dissolved organic matter), suspended particles, amino acids and chlorophyll a. Pyrosequencing of 16S rRNA genes from selected samples confirmed significant differences between river, coastal and sea samples. The PA fraction was only different (15.7% similarity) from the FL one in the open sea sample. Furthermore, PA samples generally showed higher diversity (Shannon, Simpson and Chao indices) than FL samples. At the class level, Opitutae was most abundant in the PA fraction of the sea sample, followed by Flavobacteria and Gammaproteobacteria, while the FL sea sample was dominated by Alphaproteobacteria. Finally, for the coast and river samples and both PA and FL fractions, Betaproteobacteria, Alphaproteobacteria and Actinobacteria were dominant. These results highlight the coexistence of particle specialists and generalists and the role of particle quality in structuring bacterial communities in the area. These results may also

  13. Photophysical Diversity of Water-Soluble Fluorescent Conjugated Polymers Induced by Surfactant Stabilizers for Rapid and Highly Selective Determination of 2,4,6-Trinitrotoluene Traces.

    Science.gov (United States)

    Alizadeh, Naader; Akbarinejad, Alireza; Ghoorchian, Arash

    2016-09-21

    The increasing application of fluorescence spectroscopy in development of reliable sensing platforms has triggered a lot of research interest for the synthesis of advanced fluorescent materials. Herein, we report a simple, low-cost strategy for the synthesis of a series of water-soluble conjugated polymer nanoparticles with diverse emission range using cationic (hexadecyltrimethylammonium bromide, CTAB), anionic (sodium dodecylbenzenesulfonate, SDBS), and nonionic (TX114) surfactants as the stabilizing agents. The role of surfactant type on the photophisical and sensing properties of resultant polymers has been investigated using dynamic light scattering (DLS), FT-IR, UV-vis, fluorescence, and energy dispersive X-ray (EDS) spectroscopies. The results show that the surface polarity, size, and spectroscopic and sensing properties of conjugated polymers could be well controlled by the proper selection of the stabilizer type. The fluorescent conjugated polymers exhibited fluorescence quenching toward nitroaromatic compounds. Further studies on the fluorescence properties of conjugated polymers revealed that the emission of the SDBS stabilized polymer, N-methylpolypyrrole-SDBS (NMPPY-SDBS), is strongly quenched by 2,4,6-trinitrotoluene molecule with a large Stern -Volmer constant of 59 526 M(-1) and an excellent detection limit of 100 nM. UV-vis and cyclic voltammetry measurements unveiled that fluorescence quenching occurs through a charge transfer mechanism between electron rich NMPPY-SDBS and electron deficient 2,4,6-trinitrotoluene molecules. Finally, the as-prepared conjugated polymer and approach were successfully applied to the determination of 2,4,6-trinitrotoluene in real water samples.

  14. On conservation and development of architecture and environment in the construction of large-scale national infrastructure——Exemptified by the Jiangsu Section of the Eastern Route South-to-North Water Diversion Project

    Institute of Scientific and Technical Information of China (English)

    DUAN Jin; LUO dianLi; WANG XingPing; TANG Jun; YU Gang

    2009-01-01

    The water-diverting route project's characteristics,natural landscapes,and histories and humanism of the Jiangsu Section of the Eastern Route South-to-North Water Diversion Project were systemically analyzed through proposing and studying the canal culture routes,the water resources heritage corridors,the landscape and recreation corridors,and the town economic corridors.The station areas along the water-diverting route were scientifically zoned and graded through quantitative and qualitative synthetic methods.Both planning compendiums and construction controlling methods were proposed based on the project grades of points,lines,and areas.Conservation and development of architecture and environment in the large-scale national infrastructure construction were explored systemically.Theories and methods of developing harmonious water-supplying functions,ecological functions,landscape effects,and cultural effects of large-scale water resources were examined.

  15. On conservation and development of architecture and environment in the construction of large-scale national infrastructure——Exemplified by the Jiangsu Section of the Eastern Route South-to-North Water Diversion Project

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    The water-diverting route project’s characteristics,natural landscapes,and histories and humanism of the Jiangsu Section of the Eastern Route South-to-North Water Diversion Project were systemically analyzed through proposing and studying the canal culture routes,the water resources heritage corridors,the landscape and recreation corridors,and the town economic corridors.The station areas along the water-diverting route were scientifically zoned and graded through quantitative and qualitative synthetic methods.Both planning compendiums and construction controlling methods were proposed based on the project grades of points,lines,and areas.Conservation and development of architecture and environment in the large-scale national infrastructure construction were explored systemically.Theories and methods of developing harmonious water-supplying functions,ecological functions,landscape effects,and cultural effects of large-scale water resources were examined.

  16. Development of a Safeguards Verification Method and Instrument to Detect Pin Diversion from Pressurized Water Reactor (PWR) Spent Fuel Assemblies Phase I Study

    Energy Technology Data Exchange (ETDEWEB)

    Ham, Y S; Sitaraman, S

    2008-12-24

    A novel methodology to detect diversion of spent fuel from Pressurized Water Reactors (PWR) has been developed in order to address a long unsolved safeguards verification problem for international safeguards community such as International Atomic Energy Agency (IAEA) or European Atomic Energy Community (EURATOM). The concept involves inserting tiny neutron and gamma detectors into the guide tubes of a spent fuel assembly and measuring the signals. The guide tubes form a quadrant symmetric pattern in the various PWR fuel product lines and the neutron and gamma signals from these various locations are processed to obtain a unique signature for an undisturbed fuel assembly. Signatures based on the neutron and gamma signals individually or in a combination can be developed. Removal of fuel pins from the assembly will cause the signatures to be visibly perturbed thus enabling the detection of diversion. All of the required signal processing to obtain signatures can be performed on standard laptop computers. Monte Carlo simulation studies and a set of controlled experiments with actual commercial PWR spent fuel assemblies were performed and validated this novel methodology. Based on the simulation studies and benchmarking measurements, the methodology developed promises to be a powerful and practical way to detect partial defects that constitute 10% or more of the total active fuel pins. This far exceeds the detection threshold of 50% missing pins from a spent fuel assembly, a threshold defined by the IAEA Safeguards Criteria. The methodology does not rely on any operator provided data like burnup or cooling time and does not require movement of the fuel assembly from the storage rack in the spent fuel pool. A concept was developed to build a practical field device, Partial Defect Detector (PDET), which will be completely portable and will use standard radiation measuring devices already in use at the IAEA. The use of the device will not require any information provided

  17. Kinetics and Mechanisms of Phosphorus Adsorption in Soils from Diverse Ecological Zones in the Source Area of a Drinking-Water Reservoir

    Science.gov (United States)

    Zhang, Liang; Loáiciga, Hugo A.; Xu, Meng; Du, Chao; Du, Yun

    2015-01-01

    On-site soils are increasingly used in the treatment and restoration of ecosystems to harmonize with the local landscape and minimize costs. Eight natural soils from diverse ecological zones in the source area of a drinking-water reservoir in central China are used as adsorbents for the uptake of phosphorus from aqueous solutions. The X-ray fluorescence (XRF) spectrometric and BET (Brunauer-Emmett-Teller) tests and the Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectral analyses are carried out to investigate the soils’ chemical properties and their potential changes with adsorbed phosphorous from aqueous solutions. The intra-particle diffusion, pseudo-first-order, and pseudo-second-order kinetic models describe the adsorption kinetic processes. Our results indicate that the adsorption processes of phosphorus in soils occurred in three stages and that the rate-controlling steps are not solely dependent on intra-particle diffusion. A quantitative comparison of two kinetics models based on their linear and non-linear representations, and using the chi-square (χ2) test and the coefficient of determination (r2), indicates that the adsorptive properties of the soils are best described by the non-linear pseudo-second-order kinetic model. The adsorption characteristics of aqueous phosphorous are determined along with the essential kinetic parameters. PMID:26569278

  18. Penalty model for delay of bidding section construction period in South-to-North Water Diversion Eastern Route Project from perspective of programs

    Directory of Open Access Journals (Sweden)

    Jing-chun FENG

    2012-09-01

    Full Text Available According to the multi-project and program management theory, this paper analyzes the program generation principle and establishes a program based on progress goals. On the basis of the present situation of calculation of penalty for delay of the bidding section construction period with the critical path method, we studied the effects of contractor-induced delay of the bidding section construction period in detail, including the effects on the construction period of the bidding section itself, the earliest start times of the next bidding section and other subsequent bidding sections, and the construction period of the program, and then constructed a penalty model for delay of the bidding section construction period from the perspective of programs. Using the penalty model, we conducted a practical analysis of penalty for delay of the construction period of the Baoying station program in the South-to-North Water Diversion Project. The model can help determine the amount of penalty for delay of the construction period in bidding sections scientifically and reasonably.

  19. Genotypic and phenotypic diversity of Ralstonia pickettii and Ralstonia insidiosa isolates from clinical and environmental sources including High-purity Water.

    LENUS (Irish Health Repository)

    Ryan, Michael P

    2011-08-30

    Abstract Background Ralstonia pickettii is a nosocomial infectious agent and a significant industrial contaminant. It has been found in many different environments including clinical situations, soil and industrial High Purity Water. This study compares the phenotypic and genotypic diversity of a selection of strains of Ralstonia collected from a variety of sources. Results Ralstonia isolates (fifty-nine) from clinical, industrial and environmental origins were compared genotypically using i) Species-specific-PCR, ii) PCR and sequencing of the 16S-23S rRNA Interspatial region (ISR) iii) the fliC gene genes, iv) RAPD and BOX-PCR and v) phenotypically using biochemical testing. The species specific-PCR identified fifteen out of fifty-nine designated R. pickettii isolates as actually being the closely related species R. insidiosa. PCR-ribotyping of the 16S-23S rRNA ISR indicated few major differences between the isolates. Analysis of all isolates demonstrated different banding patterns for both the RAPD and BOX primers however these were found not to vary significantly. Conclusions R. pickettii species isolated from wide geographic and environmental sources appear to be reasonably homogenous based on genotypic and phenotypic characteristics. R. insidiosa can at present only be distinguished from R. pickettii using species specific PCR. R. pickettii and R. insidiosa isolates do not differ significantly phenotypically or genotypically based on environmental or geographical origin.

  20. Kinetics and Mechanisms of Phosphorus Adsorption in Soils from Diverse Ecological Zones in the Source Area of a Drinking-Water Reservoir.

    Science.gov (United States)

    Zhang, Liang; Loáiciga, Hugo A; Xu, Meng; Du, Chao; Du, Yun

    2015-11-10

    On-site soils are increasingly used in the treatment and restoration of ecosystems to harmonize with the local landscape and minimize costs. Eight natural soils from diverse ecological zones in the source area of a drinking-water reservoir in central China are used as adsorbents for the uptake of phosphorus from aqueous solutions. The X-ray fluorescence (XRF) spectrometric and BET (Brunauer-Emmett-Teller) tests and the Scanning Electron Microscopy (SEM) and Fourier Transform Infrared (FTIR) spectral analyses are carried out to investigate the soils' chemical properties and their potential changes with adsorbed phosphorous from aqueous solutions. The intra-particle diffusion, pseudo-first-order, and pseudo-second-order kinetic models describe the adsorption kinetic processes. Our results indicate that the adsorption processes of phosphorus in soils occurred in three stages and that the rate-controlling steps are not solely dependent on intra-particle diffusion. A quantitative comparison of two kinetics models based on their linear and non-linear representations, and using the chi-square (χ2) test and the coefficient of determination (r2), indicates that the adsorptive properties of the soils are best described by the non-linear pseudo-second-order kinetic model. The adsorption characteristics of aqueous phosphorous are determined along with the essential kinetic parameters.

  1. Genetic diversity of Vibrio parahaemolyticus strains isolated from farmed Pacific white shrimp and ambient pond water affected by acute hepatopancreatic necrosis disease outbreak in Thailand.

    Science.gov (United States)

    Chonsin, Kaknokrat; Matsuda, Shigeaki; Theethakaew, Chonchanok; Kodama, Toshio; Junjhon, Jiraphan; Suzuki, Yasuhiko; Suthienkul, Orasa; Iida, Tetsuya

    2016-01-01

    Acute hepatopancreatic necrosis disease (AHPND) is an emerging shrimp disease that causes massive die-offs in farmed shrimps. Recent outbreaks of AHPND in Asia have been causing great losses for shrimp culture and have become a serious socioeconomic problem. The causative agent of AHPND is Vibrio parahaemolyticus, which is typically known to cause food-borne gastroenteritis in humans. However, there have been few reports of the epidemiology of V. parahaemolyticus AHPND strains, and the genetic relationship among AHPND strains is unclear. Here, we report the genetic characterization of V. parahaemolyticus strains isolated from AHPND outbreaks in Thailand. We found eight isolates from AHPND-suspected shrimps and pond water that were positive for AHPND markers AP1 and AP2. PCR analysis confirmed that none of these eight AP-positive AHPND strains possesses the genes for the conventional virulence factors affecting to humans, such as thermostable direct hemolysin (TDH), TDH-related hemolysin (TRH) and type III secretion system 2. Phylogenetic analysis by multilocus sequence typing showed that the AHPND strains are genetically diverse, suggesting that AHPND strains were not derived from a single genetic lineage. Our study represents the first report of molecular epidemiology of AHPND-causing V. parahaemolyticus strains using multilocus sequence typing, and provides an insight into their evolutionary mechanisms.

  2. Kinetics and Mechanisms of Phosphorus Adsorption in Soils from Diverse Ecological Zones in the Source Area of a Drinking-Water Reservoir

    Directory of Open Access Journals (Sweden)

    Liang Zhang

    2015-11-01

    Full Text Available On-site soils are increasingly used in the treatment and restoration of ecosystems to harmonize with the local landscape and minimize costs. Eight natural soils from diverse ecological zones in the source area of a drinking-water reservoir in central China are used as adsorbents for the uptake of phosphorus from aqueous solutions. The X-ray fluorescence (XRF spectrometric and BET (Brunauer-Emmett-Teller tests and the Scanning Electron Microscopy (SEM and Fourier Transform Infrared (FTIR spectral analyses are carried out to investigate the soils’ chemical properties and their potential changes with adsorbed phosphorous from aqueous solutions. The intra-particle diffusion, pseudo-first-order, and pseudo-second-order kinetic models describe the adsorption kinetic processes. Our results indicate that the adsorption processes of phosphorus in soils occurred in three stages and that the rate-controlling steps are not solely dependent on intra-particle diffusion. A quantitative comparison of two kinetics models based on their linear and non-linear representations, and using the chi-square (χ2 test and the coefficient of determination (r2, indicates that the adsorptive properties of the soils are best described by the non-linear pseudo-second-order kinetic model. The adsorption characteristics of aqueous phosphorous are determined along with the essential kinetic parameters.

  3. Water

    Science.gov (United States)

    Leopold, Luna Bergere; Baldwin, Helene L.

    1962-01-01

    What do you use water for?If someone asked you this question you would probably think right away of water for drinking. Then you would think of water for bathing, brushing teeth, flushing the toilet. Your list would get longer as you thought of water for cooking, washing the dishes, running the garbage grinder. Water for lawn watering, for play pools, for swimming pools, for washing the car and the dog. Water for washing machines and for air conditioning. You can hardly do without water for fun and pleasure—water for swimming, boating, fishing, water-skiing, and skin diving. In school or the public library, you need water to wash your hands, or to have a drink. If your home or school bursts into flames, quantities of water are needed to put it out.In fact, life to Americans is unthinkable without large supplies of fresh, clean water. If you give the matter a little thought, you will realize that people in many countries, even in our own, may suffer from disease and dirt simply because their homes are not equipped with running water. Imagine your own town if for some reason - an explosion, perhaps - water service were cut off for a week or several weeks. You would have to drive or walk to a neighboring town and bring water back in pails. Certainly if people had to carry water themselves they might not be inclined to bathe very often; washing clothes would be a real chore.Nothing can live without water. The earth is covered by water over three-fourths of its surface - water as a liquid in rivers, lakes and oceans, and water as ice and snow on the tops of high mountains and in the polar regions. Only one-quarter of our bodies is bone and muscle; the other three-fourths is made of water. We need water to live, and so do plants and animals. People and animals can live a long time without food, but without water they die in a few days. Without water, everything would die, and the world would turn into a huge desert.

  4. Diversity Management

    DEFF Research Database (Denmark)

    Ravazzani, Silvia

    2016-01-01

    This entry provides an overview of diversity management which, in the context of organizations, consists in the strategic process of harnessing the potential of all employees to create an inclusive environment and, at the same time, contribute to meeting organizational goals. The entry first...... describes the complex construct of diversity that has been variously conceptualized in the literature, embracing multiple social and informational diversity dimensions such as gender, age, culture, values, and workstyle. This is followed by illustration of the historical development of diversity-management...... discourse and practice, and possible overarching approaches guiding organizations. It goes on to elucidate elements linked to the implementation of diversity management: positive and negative outcomes, most spread practices including communication, and contingency factors shaping the understanding...

  5. Opportunities for Process-Based Management of Rivers Below Water Diversions: Exploring and Exploiting Coupled Alteration of Flow and Sediment Regimes

    Science.gov (United States)

    Kibler, K. M.; Alipour, M.

    2015-12-01

    In mountainous, rural catchments throughout the world, small to medium-sized rivers are being developed for diversion hydropower. Previous study indicates that in the absence of careful management, consequences to rivers downstream of diversion hydropower dams can be severe. However, patterns of hydrologic alteration below diversion hydropower dams have not been well described. In addition, diversion hydropower projects typically require some form of sediment management to maintain relatively small impoundments at diversion sites. Investigation of principal coupled processes, notably flow and sediment dynamics, in the context of alteration by diversion schemes may elucidate potential for working with natural processes to mitigate consequences to rivers. This analysis characterizes hydrologic alteration by diversion hydropower dams, investigating flows below 31 diversion dams. Diversion for hydropower production generated distinctive signatures of hydrologic alteration in sample rivers. For instance, flow signals were characterized by reduced low to moderate flows and steep transitions between low and high stages. In a number of rivers, small floods were reduced in number and size. However, effect to magnitude and timing of large floods was minimal across all rivers investigated. Sediments were stored in impoundments and released in pulses annually through lower sediment gates. The hydrologic signatures observed were strongly linked to diversion designs and may be transferable to other rivers developed with similar infrastructure. Understanding characteristic flow alterations due to diversion hydropower, in combination with cycles of sediment storage and release, may inform management practices for simultaneously maintaining reservoirs and downstream channels. In particular, investigating altered flood magnitudes and frequencies in the context of geomorphic work may indicate potential for maintaining natural hydrogeomorphic processes. Detailed study of sediment

  6. Water

    Science.gov (United States)

    ... Lead Poisoning Prevention Training Center (HHLPPTC) Training Tracks Water Language: English Español (Spanish) Recommend on Facebook Tweet Share Compartir For information about lead in water in Flint, MI, please visit http://www.phe. ...

  7. Everyday Diversity

    Directory of Open Access Journals (Sweden)

    Christina Ho

    2015-03-01

    Full Text Available The Cosmopolitan Civil Societies Journal has been an important forum for discussing issues around cultural diversity. Articles on cultural diversity have been present in virtually every issue of the journal. These have ranged from conceptual pieces on cosmopolitanism, identity, dialogue, prejudice, pluralism, cultural and social capital and social inclusion, to articles embedded in empirical research on ethnic precincts and segregation in cities, experiences of religious minorities, immigrant entrepreneurs, and more. Over its five year history, the journal has also had themed editions on cultural diversity issues, including one on embracing diversity in sport, and another on the Chinese in Australian politics. The scope of this work has been wide, and authors have brought a range of disciplinary and methodological approaches to the journal.   The purpose of this paper is to draw together some of the work that has been published around cultural diversity, particularly relating to everyday experiences of cosmopolitanism and racism. Focusing on everyday social relations has been an important part of recent scholarship on cultural diversity in Australia (e.g. Wise and Velayutham 2009. In contrast to research framed around multicultural policy or mediated representations of diversity, the scholarship of the ‘everyday’ aims to explore people’s lived experiences and daily interactions with others.

  8. 南水北调中线工程核心水源区水安全模糊综合评价%Fuzzy Comprehensive Evaluation of Water Security in Central Water Source Area of Middle Route of South-to-North Water Diversion Project

    Institute of Scientific and Technical Information of China (English)

    张中旺; 江华军; 李长安; 杨建; 孙小舟

    2012-01-01

    The central water source area of the Middle Route of the South-to-North Water Diversion Project is mainly located in Shiyan City of Hubei Province,and the water quality of this area basically meets the water transfer requirements. However, the water security problems,such as the soil and water loss,water pollution,immigration allocation,and the poverty and backwardness, can affect the quality of water transfer, the water resources allocation,and the sustainable development of society, economy and ecological environment Therefore, the evaluation of water security in the water source area is urgent Due to the complexity and fussiness of the meaning and evaluation of water security, a multi-layer fuzzy comprehensive evaluation method, which is based on the selection of 20 representative indexes and the development of the index system,is used to provide a quantitative assessment of the water security in the central water source area of Shiyan City located in the Middle Route of the South-to-North Water Diversion Project. The results show that the water security of the water source area has been in a critical state of basic safety since the implementation of the Middle Route of the South-to-North Water Diversion Project, which is consistent with the results obtained from the principal component analysis. Therefore, the method is feasible and it can provide a reliable conclusion%南水北调中线核心水源区主要在湖北省十堰市境内,其水源区水质基本达到调水要求,但水土流失、水体污染、移民安置、贫困与落后等水安全问题直接关乎到调水的质量、水资源的配置及社会、经济和生态环境的可持续发展,因此,水源区的水安全评价已是当务之急.针对水安全内涵及其评价的复杂性和模糊性,在选取20个代表性指标及建立评价指标体系的基础上,采用多层次模糊综合评判的方法,对南水北调中线工程核心水源区的十堰市水安全进行了定量的评

  9. Understanding Diversity

    NARCIS (Netherlands)

    D.L. van Knippenberg (Daan)

    2007-01-01

    textabstractDaan van Knippenberg is Professor of Organizational Behavior at RSM Erasmus University, Erasmus University Rotterdam, The Netherlands. His research interests include work group performance, especially work group diversity and group decision making, leadership, in particular the roles of

  10. Gender Diversities

    DEFF Research Database (Denmark)

    Agustin, Lise Rolandsen; Siim, Birte

    2014-01-01

    The article analyses the European Year for Combating Poverty and Social Exclusion (2010) (EY 2010) with the aim of identifying the nature of gender diversities in EU policies. We argue that the EU handles issues related to gender and diversity in particular ways; this approach is characterized...... by non-citizen/citizen and redistribution/recognition divisions. Employing intersectionality as the methodological approach to gender diversities, the article shows how gender and ethnicity are articulated in the policy-making process which led to the adoption of EY 201, the activities undertaken during...... the EY 2010, and the evaluation of EY 2010. The case study is suitable for developing a dynamic multi-level model for analysing gendered diversities at the transnationmal level: It illustrates how the EU policy frame interacts with particular national contexts in promoting or hundering the advancement...

  11. Understanding Diversity

    NARCIS (Netherlands)

    D.L. van Knippenberg (Daan)

    2007-01-01

    textabstractDaan van Knippenberg is Professor of Organizational Behavior at RSM Erasmus University, Erasmus University Rotterdam, The Netherlands. His research interests include work group performance, especially work group diversity and group decision making, leadership, in particular the roles of

  12. Investment plan and management of water sources project for Middle Route Project of South to North Water Diversion%南水北调中线水源工程投资计划与管理

    Institute of Scientific and Technical Information of China (English)

    郭武山

    2015-01-01

    The investment control of water sources project for Middle Route Project of South to North Water Diversion was im-plemented according to the principle of "static control and dynamic management". The investment plan and implementation are summarized. In the light of the unfavorable conditions such as the long contract construction period, short effective construction period, large workload of old dam defect treatment, quick rising of labor cost etc. in the construction process, the investment control measures are introduced from the aspects of budget prepare, investment plan, price difference adjustment, important de-sign change etc. Through these measures, the investment of the project was controlled within the approved budget.%南水北调中线水源工程按照“静态控制,动态管理”的要求对工程投资进行控制。着重对工程的投资计划和执行情况进行了总结。针对大坝加高过程中,合同工期长而有效工期短、老坝缺陷处理量大和人工费用上涨较快等不利外部条件,从项目管理预算编制、投资计划、工程价差调整、重大设计变更等方面对投资控制措施进行了介绍。通过采取上述措施,水源工程的投资可控制在批复的概算之内。

  13. Water

    CSIR Research Space (South Africa)

    Van Wyk, Llewellyn V

    2010-08-01

    Full Text Available Water scarcity is without a doubt on of the greatest threats to the human species and has all the potential to destabilise world peace. Falling water tables are a new phenomenon. Up until the development of steam and electric motors, deep groudwater...

  14. Water

    Directory of Open Access Journals (Sweden)

    E. Sanmuga Priya

    2017-05-01

    Full Text Available Phytoremediation through aquatic macrophytes treatment system (AMATS for the removal of pollutants and contaminants from various natural sources is a well established environmental protection technique. Water hyacinth (Eichhornia crassipes, a worst invasive aquatic weed has been utilised for various research activities over the last few decades. The biosorption capacity of the water hyacinth in minimising various contaminants present in the industrial wastewater is well studied. The present review quotes the literatures related to the biosorption capacity of the water hyacinth in reducing the concentration of dyestuffs, heavy metals and minimising certain other physiochemical parameters like TSS (total suspended solids, TDS (total dissolved solids, COD (chemical oxygen demand and BOD (biological oxygen demand in textile wastewater. Sorption kinetics through various models, factors influencing the biosorption capacity, and role of physical and chemical modifications in the water hyacinth are also discussed.

  15. Diversity's Calling

    Science.gov (United States)

    Cooper, Kenneth J.

    2011-01-01

    This article discusses how a Harvard-educated scholar of English and poetry, Dr. M. Lee Pelton puts a prominent face on changes that are underway at Boston's Emerson College. Faced with a public controversy over its limited faculty diversity, Emerson College has responded with a spate of hirings and promotions of minorities, capped by the…

  16. Exposing diversity

    DEFF Research Database (Denmark)

    Nørtoft, Kamilla; Nordentoft, Helle Merete

    in the homes of older people and in pedagogical institutions targeting older people. In the paper we look at the potentials and challenges in working with ethnographic video narratives as a pedagogical tool. Our findings indicate that the use of video narratives has the potential to expose the diversity...

  17. Generational diversity.

    Science.gov (United States)

    Kramer, Linda W

    2010-01-01

    Generational diversity has proven challenges for nurse leaders, and generational values may influence ideas about work and career planning. This article discusses generational gaps, influencing factors and support, and the various generational groups present in today's workplace as well as the consequences of need addressing these issues. The article ends with a discussion of possible solutions.

  18. Diversity of Microbial Communities in Production and Injection Waters of Algerian Oilfields Revealed by 16S rRNA Gene Amplicon 454 Pyrosequencing.

    Directory of Open Access Journals (Sweden)

    Nesrine Lenchi

    Full Text Available The microorganisms inhabiting many petroleum reservoirs are multi-extremophiles capable of surviving in environments with high temperature, pressure and salinity. Their activity influences oil quality and they are an important reservoir of enzymes of industrial interest. To study these microbial assemblages and to assess any modifications that may be caused by industrial practices, the bacterial and archaeal communities in waters from four Algerian oilfields were described and compared. Three different types of samples were analyzed: production waters from flooded wells, production waters from non-flooded wells and injection waters used for flooding (water-bearing formations. Microbial communities of production and injection waters appeared to be significantly different. From a quantitative point of view, injection waters harbored roughly ten times more microbial cells than production waters. Bacteria dominated in injection waters, while Archaea dominated in production waters. Statistical analysis based on the relative abundance and bacterial community composition (BCC revealed significant differences between production and injection waters at both OTUs0.03 and phylum level. However, no significant difference was found between production waters from flooded and non-flooded wells, suggesting that most of the microorganisms introduced by the injection waters were unable to survive in the production waters. Furthermore, a Venn diagram generated to compare the BCC of production and injection waters of one flooded well revealed only 4% of shared bacterial OTUs. Phylogenetic analysis of bacterial sequences indicated that Alpha-, Beta- and Gammaproteobacteria were the main classes in most of the water samples. Archaeal sequences were only obtained from production wells and each well had a unique archaeal community composition, mainly belonging to Methanobacteria, Methanomicrobia, Thermoprotei and Halobacteria classes. Many of the bacterial genera

  19. Diversity of Microbial Communities in Production and Injection Waters of Algerian Oilfields Revealed by 16S rRNA Gene Amplicon 454 Pyrosequencing.

    Science.gov (United States)

    Lenchi, Nesrine; Inceoğlu, Ozgül; Kebbouche-Gana, Salima; Gana, Mohamed Lamine; Llirós, Marc; Servais, Pierre; García-Armisen, Tamara

    2013-01-01

    The microorganisms inhabiting many petroleum reservoirs are multi-extremophiles capable of surviving in environments with high temperature, pressure and salinity. Their activity influences oil quality and they are an important reservoir of enzymes of industrial interest. To study these microbial assemblages and to assess any modifications that may be caused by industrial practices, the bacterial and archaeal communities in waters from four Algerian oilfields were described and compared. Three different types of samples were analyzed: production waters from flooded wells, production waters from non-flooded wells and injection waters used for flooding (water-bearing formations). Microbial communities of production and injection waters appeared to be significantly different. From a quantitative point of view, injection waters harbored roughly ten times more microbial cells than production waters. Bacteria dominated in injection waters, while Archaea dominated in production waters. Statistical analysis based on the relative abundance and bacterial community composition (BCC) revealed significant differences between production and injection waters at both OTUs0.03 and phylum level. However, no significant difference was found between production waters from flooded and non-flooded wells, suggesting that most of the microorganisms introduced by the injection waters were unable to survive in the production waters. Furthermore, a Venn diagram generated to compare the BCC of production and injection waters of one flooded well revealed only 4% of shared bacterial OTUs. Phylogenetic analysis of bacterial sequences indicated that Alpha-, Beta- and Gammaproteobacteria were the main classes in most of the water samples. Archaeal sequences were only obtained from production wells and each well had a unique archaeal community composition, mainly belonging to Methanobacteria, Methanomicrobia, Thermoprotei and Halobacteria classes. Many of the bacterial genera retrieved had already

  20. Stability Analysis of Lining Structure of Water Diversion Tunnel of Hydropower in Earthquake Area%强震区水电站引水隧洞衬砌结构动力稳定性分析

    Institute of Scientific and Technical Information of China (English)

    刘立新

    2016-01-01

    为了获得100年超越概率1%的地震作用下水电站引水隧洞衬砌结构的动力稳定性,采用动力时程法对某大型水电站的引水隧洞进行了三维动力分析,得到了引水隧洞各个关键位置在地震作用下的应力、位移、加速度的响应及塑性区分布特征。计算结果表明:引水隧洞的衬砌结构均按照激励地震动做相似的受迫振动,地震动峰值越大,衬砌结构的动位移和拉、压应力就越大。在引水隧洞进口处的上平段的拉、压应力最大,最大拉应力为1.3 MPa。隧洞衬砌拉应力在水平向上并不对称,每条隧洞靠近另一条隧洞的一侧,应力值较大,而远离另一条隧洞的一侧,应力值较小。引水洞塑性区离隧洞进、出口距离愈远,塑性区范围愈小,8条引水洞之间围岩的塑性区均未发生贯通。地震作用结束后,8条引水隧洞的围岩只有在出口位置发生塑性区贯通。引水隧洞在100年超越概率1%的地震工况下,局部会发生破坏,但整体上是安全稳定的。%To obtain dynamic stability of lining structure of water diversion tunnel under the 100 years beyond 1% proba-bility earthquake condition,the three-dimensional dynamic analysis for water diversion tunnel of large hydropower station is conducted by the dynamic time history method.The distribution of plastic zone and response characteristics of the stress and the displacement and acceleration of each key position of water diversion tunnel under earthquake is obtained.It is shown that the lining structure of the diversion tunnel makes similar forced vibration in accordance with the excitation earthquake. The peak value of earthquake is larger,the dynamic displacement,tensile stress and compressive stress of lining structure is greater.The compressive stress and tensile stress of the diversion tunnel inlet on the horizontal section is the biggest.The maximum tensile stress is 1.3 MPa

  1. Troubling Diversity?

    DEFF Research Database (Denmark)

    Jæger, Kirsten; Jensen, Annie Aarup

    2009-01-01

    Focussing on the cultural encounter between nurses and ethnic minority patients in Danish hospitals, this paper presents the results of a comprehensive analysis of nursing discourses on cultural difference and intercultural contact. Articles from the Danish professional journal ‘The Nurse......', published in the period from 2000 to 2008, pertaining to cultural contact and intercultural understanding have been analyzed in order to uncover nurses' experience of ethnic and cultural diversity and the ways, in which these experiences challenge their cultural and professional expertise. Results...... are related to recent contributions to diversity management theory and intercultural communication theory, calling for a strengthened focus on the historical, political, and social dimensions of intercultural contact. In continuation of these trends, an alternative, theoretical framework...

  2. Doing Diversity

    DEFF Research Database (Denmark)

    Just, Sine Nørholm; Christiansen, Tanja Juul

    2012-01-01

    Questions of agency in text–audience relations are less studied than other aspects of rhetorical agency. We suggest conceptualizing and analyzing the relationship between texts and audiences from the perspective of performativity, as it has been developed by Judith Butler. Thus, we argue that tex...... demonstrate the explanatory potential of the performative framework. Subsequently, we discuss how the concept of personae may provide a basis for alternatives to the restrictive positioning that currently dominates diversity management rhetoric....

  3. Teaching Diversity

    OpenAIRE

    Kay Young McChesney

    2015-01-01

    This article is targeted to faculty teaching race and ethnicity, racism, diversity, and multicultural courses. Many students equate race with skin color. The premise of this article is that to teach students about the social construction of race, teachers must first know enough science to teach students that race is not biological. This article examines the biology of race by showing how advances in DNA sequencing led ...

  4. Prevalence and genetic diversity of Campylobacter spp. in environmental water samples from a 100-square-kilometer predominantly dairy farming area.

    Science.gov (United States)

    Kemp, R; Leatherbarrow, A J H; Williams, N J; Hart, C A; Clough, H E; Turner, J; Wright, E J; French, N P

    2005-04-01

    Water samples were taken systematically from a 100-km2 area of mainly dairy farmland in northwestern England and examined for Campylobacter spp. Pulsed-field gel electrophoresis-restriction fragment length polymorphism (PFGE-RFLP) and flaA strain typing of Campylobacter jejuni and Campylobacter coli isolates were done. Data on the water source and the adjacent environment were recorded and examined as explanatory variables. Campylobacter spp. were isolated from 40.5% (n = 119) of the water samples tested. C. jejuni was isolated from 14.3%, C. coli was isolated from 18.5%, and Campylobacter lari was isolated from 4.2% of the samples. Campylobacter hyointestinalis was not isolated from any water source. The difference in prevalence between water types (trough, running, and standing) was significant (P = 0.001). C. jejuni was the species most commonly isolated from trough-water and running-water sources, while C. coli was the most frequently isolated from standing water (P area. Most of the isolates within the common flaA type were discriminated by PFGE-RFLP. These findings suggest a possible role for environmental water in the epidemiology of Campylobacter spp. in a farming environment.

  5. Water metagenomic analysis reveals low bacterial diversity and the presence of antimicrobial residues and resistance genes in a river containing wastewater from backyard aquacultures in the Mekong Delta, Vietnam.

    Science.gov (United States)

    Nakayama, Tatsuya; Tuyet Hoa, Tran Thi; Harada, Kazuo; Warisaya, Minae; Asayama, Megumi; Hinenoya, Atsushi; Lee, Joon Won; Phu, Tran Minh; Ueda, Shuhei; Sumimura, Yoshinori; Hirata, Kazumasa; Phuong, Nguyen Thanh; Yamamoto, Yoshimasa

    2017-03-01

    The environmental pathways for the dissemination of antibiotic resistance have recently received increased attention. Aquatic environments act as reservoirs or sources of antimicrobial-resistant bacteria, antimicrobial residues, and antimicrobial resistance genes (ARGs). Therefore, it is imperative to identify the role of polluted water in the dissemination of antimicrobial resistance. The aim of this study was to evaluate the antimicrobial residues, ARGs, and microbiota in the freshwater systems of the Mekong Delta. We selected 12 freshwater sites from aquacultures and rivers in Can Tho, Vietnam and analyzed them for 45 antimicrobial residues and 8 ARGs by LC/MS/MS and real-time PCR, respectively. A 16S rDNA-based metagenomic analysis was conducted to characterize the water microbiota. Residues of sulfamethoxazole (10/12) and sulfadimidine (7/12) were widely detected, together with the sulfa-resistance genes sul1 (11/12) and sul2 (9/12). Additionally, sulfamethoxazole residues and the β-lactamase-resistance gene blaCTX-M-1 were detected in eight freshwater systems (8/12), suggesting that these freshwater systems may have been polluted by human activity. The metagenomic analysis showed that all the tested freshwater systems contained the phyla Proteobacteria, Actinobacteria, and Bacteroidetes, representing 64% of the total microbiota. Moreover, the Cai Rang River site (Ri-E), which is located at the merge point of wastewaters from backyard-based aquacultures, contained the genera Polynucleobacter, Variovorax, and Limnohabitans, representing more than 78.4% of the total microbiota. Bacterial diversity analysis showed that the Ri-E exhibited the lowest diversity compared with other regions. Principal coordinate analysis showed that the differences among water microbiotas in backyard-based aquacultures could be explained by the farmers' aquaculture techniques. In conclusion, this study demonstrated a collapse of bacterial diversity at the merge point of wastewaters

  6. Phylogenetic diversity of microbial communities associated with the crude-oil, large-insoluble-particle and formation-water components of the reservoir fluid from a non-flooded high-temperature petroleum reservoir.

    Science.gov (United States)

    Kobayashi, Hajime; Endo, Keita; Sakata, Susumu; Mayumi, Daisuke; Kawaguchi, Hideo; Ikarashi, Masayuki; Miyagawa, Yoshihiro; Maeda, Haruo; Sato, Kozo

    2012-02-01

    The diversity of microbial communities associated with non-water-flooded high-temperature reservoir of the Niibori oilfield was characterized. Analysis of saturated hydrocarbons revealed that n-alkanes in crude oil from the reservoir were selectively depleted, suggesting that crude oil might be mildly biodegraded in the reservoir. To examine if any specific microorganism(s) preferentially attached to the crude oil or the other components (large insoluble particles and formation water) of the reservoir fluid, 16S rRNA gene clone libraries were constructed from each component of the reservoir fluid. The clones in the archaeal libraries (414 clones in total) represented 16 phylotypes, many of which were closely related to methanogens. The bacterial libraries (700 clones in total) were composed of 49 phylotypes belonging to one of 16 phylum-level groupings, with Firmicutes containing the greatest diversity of the phylotypes. In the crude-oil- and large-insoluble-particle-associated communities, a Methanosaeta-related phylotype dominated the archaeal sequences, whereas hydrogenotrophic methanogens occupied a major portion of sequences in the library of the formation-water-associated community. The crude-oil associated bacterial community showed the largest diversity, containing 35 phylotypes, 16 of which were not detected in the other bacterial communities. Thus, although the populations associated with the reservoir-fluid components largely shared common phylogenetic context, a specific fraction of microbial species preferentially attached to the crude oil and insoluble particles. Copyright © 2011 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. Exposing diversity

    DEFF Research Database (Denmark)

    Nørtoft, Kamilla; Nordentoft, Helle Merete

    . A prominent research theme in health care studies is, therefore, to explicate the gap between theory and practice. The question this paper addresses is how a learning environment can be designed to bridge this theory-practice gap, expose the differences in situated interactions and qualify health...... in the homes of older people and in pedagogical institutions targeting older people. In the paper we look at the potentials and challenges in working with ethnographic video narratives as a pedagogical tool. Our findings indicate that the use of video narratives has the potential to expose the diversity...

  8. Occurrence and diversity of fungal pathogens associated with water hyacinth and their potential as biocontrol agents in the Rift Valley of Ethiopia

    NARCIS (Netherlands)

    Gebregiorgis, Firehun; Struik, P.C.; Lantinga, E.A.; Tessema, Taye

    2017-01-01

    Water hyacinth poses serious socio-economic and environmental problems in Ethiopia. To integrate fungal pathogens into water hyacinth management, a survey was conducted in the Rift Valley of Ethiopia. Based on morphological characterization and DNA sequencing, 25 fungal species were identified th

  9. Quantifying the Sensitivity of Water Yield to Forest Disturbances Across a Diverse Set of Unmanaged Watersheds throughout the Continential United States

    Science.gov (United States)

    Buma, B.; Livneh, B.

    2015-12-01

    Water is one of the most critical natural systems for human and ecosystem health and well-being. Understanding the influence of changes in land cover on hydrology is critical to anticipating future water availability and impacts on agriculture/industry, ecosystems, and residential water supplies. In the United States, most major water sources originate in forested watersheds, and thus we aim to understand how changes in forest cover influence water supplies over those areas, specifically identifying which types of watersheds exhibit marked rapid changes in water yield as a result of disturbance processes (e.g., fire). Using a set of 601 primarily unmanaged watersheds (2000-2010) across the US and a 30m forest disturbance dataset, we explored the relationship between changes in water resources, measured in terms of detrended runoff ratios, and forest disturbance severity. Preliminary results find some watersheds nearly completely disturbed due to fire, while others undisturbed. Most watersheds were relatively insensitive--in terms of their expected runoff ratios--to disturbances during that time period, but several were highly sensitive. Areas which showed major increases in water yield post-disturbance generally had larger disturbances occur in areas coincident with higher average precipitation. Soils in these areas had comparatively moderate to low infiltration rates and little subsurface water exchange, and were typically at higher slopes with a lower wetland component. They also had less water storage in the system. Overall, the results from this study are expected to be broadly relevant to communities and scientists seeking to anticipate the hydrologic impacts of large-scale land-cover disturbance.

  10. FAKTOR-FAKTOR LINGKUNGAN ABIOTIK DAN KEANEKARAGAMAN PLANKTON SEBAGAI INDIKATOR KUALITAS PERAIRAN DANAU TOBA (Environmental Abiotic Factors and the Diversity of Plankton as Water Quality Indicators in Lake Toba, North Sumatera, Indonesia

    Directory of Open Access Journals (Sweden)

    Ternala Alexander Barus

    2004-07-01

    Full Text Available ABSTRAK Penelitian ini bertujuan untuk mengetahui faktor-faktor lingkungan dan keanekaragaman plankton sebagai indikator kualitas perairan Danau Toba, Sumatera Utara. Penelitian ini dilaksanakan pada bulan April – Mei 2003 pada 3 stasiun pengambilan sampel (Parapat, Simanindo dan Balige. Dari hasil penelitian diidentifikasi sebanyak 93 genera plankton (7 kelompok fitoplankton dan 2 kelompok zooplankton. Dari hasil perhitungan nilai indeks keanekaragaman Shannon-Wiener memperlihatkan bahwa komunitas plankton di ketiga lokasi pengamatan adalah mirip. Nilai indeks keanekaragaman menunjukkan bahwa perairan mengalami pencemaran sedang.   ABSTRACT The aim of the study is to investigate the environmental abiotic factors and the diversity of plankton as water quality indicators in Lake Toba ecosystem, North of Sumatera. The study was done on April to May, 2003 in three sampling stations (Parapat, Simanindo and Balige. Ninety three genera of plankton (seven groups of phytoplankton and two groups of zooplankton were identified. The calculated values of diversity index (Shannon-Wiener showed that plankton community in three stations is quite similar. The scores of diversity index were categorized into moderately polluted by organic matters.

  11. 基于SPSS软件的浦东新区长江引水量分析和预测%Analysis and Prediction of Water Diversion from the Yangtze River in the Pudong New District Based on SPSS

    Institute of Scientific and Technical Information of China (English)

    杨晓斌

    2012-01-01

    The Pudong New District is located in the outlet of the Yangtze River. The Yangtze River discharges a large number of high-quality water to the Pudong New District through the intake gate every year, which benefits the industrial and agricultural development in the district Based on the normality test,analysis of variance,and seasonal analysis and other functions embedded in the SPSS software, the water diversion amount and its variation characteristics from the Yangtze River were analyzed from 2006 to 2011 in the Pudong New District Moreover, the Expert Modeler was used to build the prediction model, which was used to simulate the water diversion amount from 2006 to 2011; therefore the simulated values were compared with the measured values. The results showed that the evaluation model is reliable and feasible. The model was then used to predict the monthly water diversion amount from 2012 to 2015, which can provide references for a better development and utilization of water resources in the Yangtze River.%浦东新区地处长江出口,每年通过沿江水闸引入大量长江优质水,服务于新区社会工农业发展.使用SPSS软件正态检验、方差分析和季节性分析等功能,对2006年-2011年浦东新区长江引水量数据进行分析,研究近年引水量的变化特征.运用专家建模器建立预测模型,使用该模型模拟2006年-2011年数据,比较拟合值和实测值,使模型可靠、可行.最后利用模型预测2012年-2015年每月引水量数据,为更好开发利用长江水资源提供依据.

  12. The Dynamic Response and Stability Analysis of Water Diversion Dike at a Nuclear Power Station%某核电站取水导流堤动力响应及稳定性分析

    Institute of Scientific and Technical Information of China (English)

    赵杰; 王桂萱; 郑洋

    2013-01-01

    将土体简化为Hardin-Drnevich等效线性模型,运用有效应力动力分析方法,得到SL1和SL2地震动作用下莱核电导流堤的稳定安全系数、液化区分布以及震后残余变形.分别采用整个地震过程中的最小安全系数和最小平均安全系数评价了导流堤的稳定性,对计算结果进行了比对.SL1地震动作用下,导流堤地基砂土液化范围较小,不会影响导流堤结构的正常使用;SL2地震动作用下,导流堤地基土层中的砂土发生了大面积的液化,导流堤发生了较大的变形,但不至于使导流堤整体向渠心滑移,不会影响到核电厂的安全用水.本文成果对类似工程抗震设计具有一定的参考价值和指导意义.%Abstract:This paper uses the Hardin-Drnevich equivalent linear model and dynamic effective stress analysis method to simulate the dynamic behavior of soil,gets the factor of safety,liquefaction zone distribution and seismic residual deformation of a diversion dike under seismic load of SL1 and SL2.The paper also uses the minimum safety factor and average minimum safety factor in the whole process of an earthquake to evaluate the stability of the diversion dike under different seismic action and evaluates the results.The liquefaction range in the diversion dike foundation is smaller under SL2 than under SL1.So it does not affect the normal use of diversion dike structure.Under seismic load of SL2,diversion dike foundation in sandy soil liquefies over a large area,resulting in large deformation.But the diversion dam does not slide down to the ditch in whole,so the use of water in the nuclear power plant is safe.The results of this paper have a certain reference value and guidance to similar engineering.

  13. Impact Analysis of Seepage Flow in Thickened Ice Cover on the Water Diversion Capacity in Canal%加厚冰盖渗流对渠道输水能力的影响

    Institute of Scientific and Technical Information of China (English)

    赵新; 张雅卓; 王旭

    2012-01-01

    The water diversion capacity during the ice age has received more and more attention from the aspects of project management and scientific research. The research on the water diversion capacity should not be limited to the normal flow conditions, such as the free-flowing period and ice covered period,and it should further extend to the special situations during the ice-flowing period. In general,the water diversion capacity during the ice-flowing period may affect and limit the water diversion capacity during the ice age. Adopting the operating measure of water diversion under a thickened ice cover can improve the water diversion capacity during the ice-flowing period. In this paper, based on the theoretical analysis and physical model experiments, the effects of seepage flow in the thickened ice cover on the water diversion capacity during the ice age were analyzed. The results showed (1) Due to the high porosity of the thickened ice cover during the frozen period, the permeability coefficient of the thickened ice cover is larger than that during ice-melting period; (2) The shape factor of ice slush (t/L) has insignificant effects on the permeability coefficient of thickened ice covers (3) With the increasing of the thickness of ice cover,the permeability coefficient of thickened ice cover decreases gradually. Especially when the thickness is less than 0. 1m, the permeability coefficient decreases rapidly; (4) With the increasing of the total flow in canal, the seepage flow in the thickened ice cover becomes larger, while the proportion of the seepage flow to the total flow decreases;and (5) The seepage flow in the thickened ice cover only accounts for a very small proportion of the total flow. Therefore, the effects of seepage flow on the water diversion capacity during the ice age are negligible.%输水渠道冰期输水能力日益成为工程运行管理、学者研究关注的焦点.输水能力的研究不能仅仅局限在正常输水期(明流期和封冻

  14. 峡江水利枢纽电站取水防沙试验研究%Experiment Study on Water Diversion and Sediment Control of Xiajiang Hydraulic Complex Project

    Institute of Scientific and Technical Information of China (English)

    黄志文; 邬年华; 苏立群; 明宗富

    2011-01-01

    For avoiding sediment silting up reservoir and flowing through power plant, the original experiment on water diversion and sediment control for Xiajiang Hydraulic Complex Project is analyzed and the arrangement of silt arrester is proposed to improve. The head of the silt arrester is extended to upstream and smoothly converged with the nature bay of river. The operation effects of the improved water diversion and sediment control are studied and the proposals on operation axe also presented herein.%为解决峡江水利枢纽泥沙淤塞库区,避免泥沙进入电站,对取水防沙原设计方案试验中存在的问题进行了分析.改进了拦沙坎的布置方案,提出拦沙坎头部上延与上游自然河湾平顺衔接,以使形成的人工弯道环流导流排沙方案为最优取水防沙方案.探讨了优化方案的取水防沙效果,提出了运行时应注意的事项.

  15. Diversity Measures

    Directory of Open Access Journals (Sweden)

    MSc. Mentor Ademaj

    2012-06-01

    Full Text Available Diversity measures are a type of non-criminal measures foreseen in the Chapter IV of the Code of Juvenile Justice, which may be imposed on juvenile perpetrators of criminal acts. These measures can be applied in cases of minor offenses, for which is foreseen the criminal sanction with a fine or imprisonment up to three years or for criminal offenses committed by negligence for which is foreseen the sentence up to five years of imprisonment, except those cases that result in death. With the imposition of these measures is intended to prevent criminal proceedings against juveniles whenever is possible, rehabilitation and reintegration of juvenile in his/her community and the prevention of recidivist behaviour. Competent authority to impose them is the public prosecutor, the juvenile judge and juvenile court. And they are executed by the Kosovo Correctional Service.

  16. Design Diversity

    DEFF Research Database (Denmark)

    Dankl, Kathrina

    2014-01-01

    The publication 'Design Diversity', an exhibition catalogue, focuses on aging and design – a product culture in transformation that aims to help change conventional notions of the later years of life. Age is positioned as a generational issue that has the same relevance for all age groups...... courageous projects for "best agers" and "golden agers" never get beyond the prototype stage, products that paint a more "beige" picture of everyday life can be found in large numbers. This fact raises some key questions: Does the existing product culture reflect today's views on old age? Do contemporary...... awareness of the fact that material culture shapes our view of aging, and therefore is also capable of changing it....

  17. Outcome of schistosomiasis control by hardening the water diversion channels located in Zhongzhou Town in Yueyang County%湖南岳阳县中洲乡东西灌渠硬化血防效果研究

    Institute of Scientific and Technical Information of China (English)

    任小兵; 方小平; 李以义; 胡本骄; 赵正元; 李善峰; 任光辉

    2016-01-01

    目的:探索引有螺水源灌渠硬化工程的血防效果。方法选择岳阳县中洲乡东西干渠硬化工程区作为研究现场,通过收集分析2006~2015年灌渠所在流行村血防措施及病情,引水口洲滩及渠道螺情变化、评估以硬化为主血防效果。结果2006~2015年引水水源现场洲滩钉螺密度徘徊在0.40只/0.11m2左右;灌渠硬化前钉螺平均密度为0.1999只/0.11 m2,感染螺平均密度为0.0018只/0.11m2;工程后2007~2015年连续9年未发现钉螺;工程区人群血吸虫感染率从6.12%下降至0.19%;家畜血吸虫感染率从14.86%下降至0。结论引有螺水源灌渠实施硬化改造后不能孳生钉螺,辅以其他常规血防措施可有效降低当地疫情。%Objective To investigate the outcomes of schistosomiasis control by hardening wa⁃ter diversion channels originated from snail ridden areas in Dongting Lake. Methods East-West main channels and their branches, which were hardened with cement and concrete and run through Zhong⁃zhou Town in Yueyang County, were selected as study sites. The information on endemic situation and measures for schistosomiasis control as well as the snail density changes in the marshland near the water inlet and within the channels were collected from 2006 to 2015 for evaluation of the outcomes after hardening the water diversion channels. Results Average snail density in between 2006 and 2016 in the marshland around water sources was fluctuated in 0.40 heads/0.11m2. The average snail density inside the water diversion channel was 0.1999heads/0.11m2, and average infected snail density was 0.0018 heads/0.11m2 before channel hardening. However, no snails were found inside the diver⁃sion works from 2007 to 2015, when the rate of schisosome infection was dropped to 0.19% from 6.12% in population living along the diversion channels, and to zero from 14.86% in domestic animals over the same period. Conclusion Hardening the water diversion

  18. Antimicrobial resistance and genetic diversity of the SXT element in Vibrio cholerae from clinical and environmental water samples in northeastern Thailand.

    Science.gov (United States)

    Mala, Wanida; Faksri, Kiatichai; Samerpitak, Kittipan; Yordpratum, Umaporn; Kaewkes, Wanlop; Tattawasart, Unchalee; Chomvarin, Chariya

    2017-08-01

    Multidrug resistance in V. cholerae has been increasing around the world including northeastern Thailand. The aquatic environment is a reservoir of V. cholerae and might be an important source of resistant strains. The aims of this study were to investigate the phylogenetic relationships of intSXT gene sequences from 31 clinical and 14 environmental V. cholerae O1 and non-O1/non-O139 isolates and 11 sequences amplified directly from environmental water samples. We also amplified class 1 integrons, the SXT elements (targeting the intSXT gene) and antimicrobial resistance genes directly from water samples. Phylogenetic analysis displayed two major distinct clusters (clusters 1 and 2). Most V. cholerae O1 (19/20, 95%) and non-O1/non-O139 isolates (8/11, 72.7%) from clinical sources, and all sequences obtained directly from water samples, belonged to cluster 1. Cluster 2 mostly comprised environmental non-O1/non-O139 isolates (10/12, 83.3%). We successfully amplified the SXT elements directly from17.5% of water samples. Associated resistance genes were also amplified as follows: sul2 (41.3% of water samples), dfrA1 (60%), dfr18 (33.8%), strB (70%) and tetA (2.5%). Class 1 integrons were not found in water samples, indicating that the SXT element was the major contributor of multidrug resistance determinants in this region. The SXT element and antimicrobial resistance genes could be transferred from clinical V. cholerae O1 to environmental V. cholerae non-O1/non-O139 was demonstrated by conjugation experiment. These findings indicate that there may have been cross dissemination and horizontal gene transfer (HGT) of the SXT element harbored by V. cholerae O1 and non-O1/non-O139 strains isolated from clinical and environmental water sources. Environmental water might be an important source of antimicrobial resistance genes in V. cholerae in this region. Direct detection of antimicrobial resistance genes in water samples can be used for monitoring the spread of such genes

  19. Diverse Land Use and the Impact on (Irrigation Water Quality and Need for Measures — A Case Study of a Norwegian River

    Directory of Open Access Journals (Sweden)

    Gro S. Johannessen

    2015-06-01

    Full Text Available Surface water is used for irrigation of food plants all over the World. Such water can be of variable hygienic quality, and can be contaminated from many different sources. The association of contaminated irrigation water with contamination of fresh produce is well established, and many outbreaks of foodborne disease associated with fresh produce consumption have been reported. The objective of the present study was to summarize the data on fecal indicators and selected bacterial pathogens to assess the level of fecal contamination of a Norwegian river used for irrigation in an area which has a high production level of various types of food commodities. Sources for fecal pollution of the river were identified. Measures implemented to reduce discharges from the wastewater sector and agriculture, and potential measures identified for future implementation are presented and discussed in relation to potential benefits and costs. It is important that the users of the water, independent of intended use, are aware of the hygienic quality and the potential interventions that may be applied. Our results suggest that contamination of surface water is a complex web of many factors and that several measures and interventions on different levels are needed to achieve a sound river and safe irrigation.

  20. 引汉济渭水权置换的管理制度创新研究%Study on Management System Innovation of Water Rights Replacement of Water Diversion from Hanjiang River to Weihe River

    Institute of Scientific and Technical Information of China (English)

    黄建水; 殷会娟; 乔钰

    2014-01-01

    Taking the Hanjiang River to the weihe River water rights as the object of study,through the exploratory analysis method,this paper solved the replacement of the Hanjiang River to the Weihe River water rights and the Yellow River water rights whether replacement of the theoreti-cal basis and the legal basis. The essence of the Hanjiang River to the Weihe River water rights replacement is increasing the total amount of water resources in the Yellow River after drawing water from the Hanjiang River to the Weihe River,increasing the area of the Yellow River water index though replacing the water index from the Weihe River water to northern area of Shaanxi Province. Through the innovation of the Yellow River water rights management system,it can realize the replacement of the Hanjiang River to the Weihe River water rights and the Yellow River water rights. The exchange management system of the Hanjiang River to the Weihe River water rights is not only the basis of increasing the Yellow River water consumption after guiding the Hanjiang River to the Weihe River water,but also is the implementation basis of replacement of water rights,and is the guiding regulation of replacing the two water rights as well.%以引汉济渭水权为研究对象,通过探索性分析方法解决了引汉济渭水权与黄河水权置换是否有理论依据和法律依据问题。引汉济渭水权置换的实质是从汉江流域调水补充渭河后使黄河水资源总量增加,把陕西省的渭河取水指标置换给陕北地区,增加该地区黄河取水指标。通过黄河水权管理制度的创新,可以实现引汉济渭水权与黄河水权的置换。引汉济渭水权置换管理制度既是引汉济渭后陕北地区增加黄河用水量的依据,又是两个水权实行置换的依据,也是两个水权实施置换的指导规范。

  1. Abundance and Diversity Index of Phytoplankton in Binzhou Shallow Sea Waters%滨州浅海海域浮游植物丰度及其多样性

    Institute of Scientific and Technical Information of China (English)

    巩俊霞; 张金路; 周长志; 王志忠; 陈述江; 段登选

    2015-01-01

    Phytoplankton was investigated for 3 times in binzhou shallow sea waters in spring, summer and autumn of 2012. Phytoplankton diversity and flora characteristics were analyzed using Shannon wiener diversity index, Pielou evenness index and McNaugton dominance index, and the results showed that a total of 40 species (genra) belonging to 4 phyla were identified. The amount of Bacillariophytaspecies were the most which accounts for 92.50%; Phytoplankton abundance was (2.66-23520.27) ×104 / m3, the average was 1525.13 ×104 / m3; Diversity index and evenness index reach the summit in autumn, then declined in spring, and summer and reached its minima in summer. The average diversity index and evenness index was 1.76 ±0.20 and 0.70 ±0.25 respectively, and both of them were better, which showed that the distribution of marine phytoplankton is evener, and its community structure was in a relatively complete and stable condition . The results of Diversity threshold level evaluation showed that the diversity of the phytoplankton waters in the spring and summer was general (Ⅱ class),and the diversity in autumn was better (Ⅲ level).%于2012年春季、季、秋季分别对滨州浅海海域的浮游植物进行调查,采用香农-威纳(Shannon-Weiner)多样性指数、Pielou均匀度指数和McNaugton优势度指数对其浮游植物多样性及群落特征进行分析。共鉴定出浮游植物4门40个属种,其中硅藻门的种类最多,占92.50%;浮游植物丰度为(2.66~23520.27)×104 ind/m3,均值1525.13×104ind/m3。多样性指数和均匀度均值分别为1.76±0.20和0.70±0.25,以秋季最高,春季次之,夏季最低,多样性指数和均匀度均较好,表明该海域浮游植物分布比较均匀,其群落结构处于较完整和稳定的状态。该海域浮游植物的多样性阈值等级评价为Ⅱ级,多样性一般,其中春季和夏季多样性一般(Ⅱ级),秋季多样性较好(Ⅲ级)。

  2. Everyone into the Water!

    Science.gov (United States)

    Hennessey, Christina L.

    2007-01-01

    As the days grow longer and warmer with the approach of summer, everyone's thoughts turn to the outdoors and the clear blue of water sports. While recreational choices range from in-the-water activities like water polo to under-the-water sports like free diving, and on-the-water diversions like water skiing, this article focuses on print, video,…

  3. Teaching Diversity

    Directory of Open Access Journals (Sweden)

    Kay Young McChesney

    2015-10-01

    Full Text Available This article is targeted to faculty teaching race and ethnicity, racism, diversity, and multicultural courses. Many students equate race with skin color. The premise of this article is that to teach students about the social construction of race, teachers must first know enough science to teach students that race is not biological. This article examines the biology of race by showing how advances in DNA sequencing led to genetics research that supports arguments that race is not biological. DNA comparisons show that all human populations living today are one species that came from Africa. The article explains the migration of humans out of Africa about 60,000 years ago and how they populated Australia, then Asia, Europe, and the Americas. The article shows how recent research maps the timing of the migration and admixture of specific population groups into Europe and India. The article shows how a mutation in one nucleotide can result in a trait like blue eyes, or Hemoglobin S (which confers resistance to malaria, which can be subject to evolution through natural selection. DNA comparisons show how natural selection shaped the genetics of human skin color to adapt to less UV light in the northern latitudes of Europe and Asia. The article shows that there is no relation between skin color or other “racial” characteristics and complex traits like intelligence. The science in this article will help teachers explain that as race is not biological, race is socially constructed and culturally enacted.

  4. 31P NMR characterization and efficiency of new types of water-insoluble phosphate fertilizers to supply plant-available phosphorus in diverse soil types.

    Science.gov (United States)

    Erro, Javier; Baigorri, Roberto; Yvin, Jean-Claude; Garcia-Mina, Jose M

    2011-03-01

    Hydroponic plant experiments demonstrated the efficiency of a type of humic acid-based water-insoluble phosphate fertilizers, named rhizosphere controlled fertilizers (RCF), to supply available phosphorus (P) to different plant species. This effect was well correlated to the root release of specific organic acids. In this context, the aims of this study are (i) to study the chemical nature of RCF using solid-state (31)P NMR and (ii) to evaluate the real efficiency of RCF matrix as a source of P for wheat plants cultivated in an alkaline and acid soil in comparison with traditional water-soluble (simple superphosphate, SSP) and water-insoluble (dicalcium phosphate, DCP) P fertilizers. The (31)P NMR study revealed the formation of multimetal (double and triple, MgZn and/or MgZnCa) phosphates associated with chelating groups of the humic acid through the formation of metal bridges. With regard to P fertilizer efficiency, the results obtained show that the RCF matrix produced higher plant yields than SSP in both types of soil, with DCP and the water-insoluble fraction from the RCF matrix (WI) exhibiting the best results in the alkaline soil. By contrast, in the acid soil, DCP showed very low efficiency, WI performed on a par with SSP, and RCF exhibited the highest efficiency, thus suggesting a protector effect of humic acid from soil fixation.

  5. Air-Liquid Partition Coefficient for a Diverse Set of Organic Compounds: Henry’s Law Constant in Water and Hexadecane

    Science.gov (United States)

    The SPARC vapor pressure and activity coefficient models were coupled to estimate Henry’s Law Constant (HLC) in water and in hexadecane for a wide range of non-polar and polar solute organic compounds without modification to/or additional parameterization of the vapor pressure or...

  6. Investigation of the Diversity of Mollusca and Evaluation of Water Quality in Hengyang Reach of Xiangjiang River%湘江衡阳段软体动物多样性调查和水质生物学评价

    Institute of Scientific and Technical Information of China (English)

    刘俊; 吴彦琼; 李静; 胡劲松; 李鹏; 刘运莲

    2011-01-01

    The species and diversity and faunal and distribution of molluscas in Hengyang reach of Xiangjiang River were studied after many years of dayuandu hydropower station built; and in virtue of diversity indexes of molluscas, water quality were evaluated. The result of the research showed that there were 45 species of mollusca in Hengyang reaches of Xiang River, which belong to 2 classes and 9 families and 18 genera. 30 species belonging to 11 genera in 6 families of Gastropoda were found, 15 specieses belonging to 7 genera in 3 families of Bivalvia were found. The mollusca was in Oriental realm. 26 species were endemic species in China, and Mekonia hunanensis was in endangered status (It has been listed in China Species Red List as an extinct species). Shannon index was used to evaluate water quality of Hengyang reaches of Xiang River. The result showed that the water quality in Dongzhou ialand and Hengshan county town belonged to clean water, the other 8 sampling sites water had been polluted slightly.%对衡山大源渡电站蓄水多年后的湘江衡阳段软体动物的种类组成、区系分布以及多样性进行了调查,并用生物多样性指数对湘江衡阳段水质进行了评价.调查结果表明,湘江衡阳段计有软体动物45种,分别隶属于2纲9科18属,其中腹足纲6科11属30种,双壳纲3科7属15种,其区系成分主要为东洋界类型;其中26种为中国特有种,且湖南湄公螺为濒危物种(被定为灭绝的物种).用软体动物的Shannon-Wiener多样性指数(H')对湘江衡阳段进行水质生物学评价,研究结果表明,湘江衡阳段的水质除东洲岛和衡山县城为清洁水外,其余8个采样点的水质均受到了轻度污染.

  7. Research on the closure law of hydraulic control slow closing butterfly valve in pressure flow water diversion system%压力流输水系统中缓闭式液控蝶阀关闭规律研究

    Institute of Scientific and Technical Information of China (English)

    刘奕朗; 高学平; 蒋琳琳

    2012-01-01

    Water diversion system of long - distance and high - lift pressure flow will produce serious damage once pump - stopping water hammer takes place. It is a simple and effective water hammer protection measure to set one hydraulic control slow closing butterfly valve at the outlet of pump with appropriate closure way. The thesis, combining practical engineering, solve the water hammer basic equations by the method of characteristics, compare the results of different valve closure way, including the envelope line of piezometric head, pressure change at outlet of pump station and rotate speed change, then proposes the appropriate way of valve closure. The results can provide a reference for the setting of pump - stopping water hammer protective measures.%对于长距离、高扬程压力流输水系统,一旦发生停泵水锤,将对输水系统产生严重危害.在泵出口设置缓闭式液控蝶阀并以适当的方式关阀是一种简单有效的水锤防护措施.本文结合实际工程,通过特征线法求解水锤基本方程,比较不同关阀方式下管路沿程压力变化、泵站出口断面压力变化及水泵转速变化,提出合适的关阀方式.研究成果可为停泵水锤防护措施的设置提供参考.

  8. Analysis on Plant Diversity Quanfu Village Basin of Water-holding Forest in of Yuanyang Terrace%元阳梯田全福庄流域水源涵养林的植物多样性分析

    Institute of Scientific and Technical Information of China (English)

    和弦; 宋维峰; 彭永刚; 王惠生; 崔吉林

    2012-01-01

    元阳梯田已有1200多年的历史,水源涵养林的存在对于梯田的延续具有重要的价值。为得到元阳梯田水源涵养林的植物多样性分布特征,对元阳梯田全福庄流域4种主要植被类型水源涵养林下的植物物种数量特征、物种丰富度、多样性、均匀度等多样性规律进行了标准样地调查。结果表明,研究区共有植物155种,隶属66科,其中,山茶科、禾本科、蓼科植物占有绝对优势,不同植被类型森林群落的优势种不同;物种丰富度大小为:次生常绿阔叶林〉杂木林〉次生落叶阔叶林〉人工水冬瓜林;物种多样性特征表现为,乔木层:次生常绿阔叶林〉次生落叶阔叶林〉杂木林〉人工水冬瓜林;灌木层:次生常绿阔叶林〉杂木林〉次生落叶阔叶林,人工水冬瓜林无灌木层分布;草本层:次生落叶阔叶林〉人工水冬瓜林〉次生常绿阔叶林〉杂木林。植被分布的物种丰富度和均匀度对物种多样性存在交叉影响。%Yuanyang terrace with over 1 200 years of history, the existence of water-holding forest has an important value for development of Yuanyang terrace. In order to investigate the distribution of plant diversity in water-holding forest of Yuanyang terrace this study adopted the method of standard statistical and on-site investigation. The study on the quantitative features, the species richness, diversity and evenness, etc. char- acteristics in 4 types of vegetation regions in Quanfu middle village basin were carried out. The results showed that there were 155 species of plants in this area, belonging to 66 families, and Theaceae, Poaceae and Polygonaceae were 3 dominant families. The different vegetation regions had different dominant species. The species richness index followed the order of secondary evergreen broad-leaved forest〉weed tree forest〉 secondary deciduous broad-leaved forest〉artificial Alder forest. Within

  9. 16S rRNA-based bacterial diversity in the organic-rich sediments underlying oxygen-deficient waters of the eastern Arabian Sea

    Digital Repository Service at National Institute of Oceanography (India)

    Divya, B.; Parvathi, A.; LokaBharathi, P.A.; Nair, S.

    zone (Fuchs et al. 2005), it was not detected in the sediment. Betaproteobacteria include ammonia oxidizers such as Nitrosospira-like clusters, which have been well documented in the OMZ waters off north Chile and marine sediments (Molina et al. 2007... Chile. Appl Environ Microbiol 73:3547-3555. Morasch B, Richnow HH, Schink B, Meckenstock RU (2001) Stable hydrogen and carbon isotope fractionation during microbial toluene degradation:mechanistic and environmental aspects. Appl Environ Microbiol 67...

  10. Impact of waste dump on surface water quality and aquatic insect diversity of Deepor Beel (Ramsar site), Assam, North-east India.

    Science.gov (United States)

    Choudhury, Dharitri; Gupta, Susmita

    2017-10-06

    Water and aquatic insects were collected seasonally from site 1, the low-lying area of the dump near Deepor Beel, and from sites 2 and 3 of the main wetland and analysed. While dissolved oxygen (DO) increased from site 1 to site 3 in each season, electrical conductivity (EC), total dissolved solid (TDS), total alkalinity (TA) and free CO2 (F-CO2) decreased. Pb and Cd were found to exceed the limits set for drinking water in all the sites and seasons. Species richness (SpR) was found highest (23) at site 2 and lowest (14) at site 1. Sensitive species was absent. The Shannon (H') values at site 1 were sites 2 and 3 were > 1 in most of the seasons. Biological monitoring scores (Biological Monitoring Working Party and Stream Invertebrate Grade Number-Average Level) in different sites and seasons inferred severely poor to moderate water quality. At site 1, significant negative correlations were seen for Pb and Cr with SpR while Ni and Cu with insect density (ID). At site 2, TA had highly significant positive correlations with SpR and ID while Cu showed negative correlation with SpR. At site 3, ID had significant negative relationships with air temperature, water temperature, depth, TA, F-CO2, PO4(3-) and Cr. Canonical correspondence analysis triplot has clearly separated site 1 associated with tolerant species and highly influenced by TA, TDS, EC, F-CO2, Cr, Ni, Cd and Zn confirming high anthropogenic activities on that site. Tolerant and semitolerant species were present at site 2 (influenced by depth and transparency) and site 3 (influenced by Pb and WT) both. Results of this study discerned that the dump site is the point source of pollution.

  11. The effect of feed water dissolved organic carbon concentration and composition on organic micropollutant removal and microbial diversity in soil columns simulating river bank filtration.

    Science.gov (United States)

    Bertelkamp, C; van der Hoek, J P; Schoutteten, K; Hulpiau, L; Vanhaecke, L; Vanden Bussche, J; Cabo, A J; Callewaert, C; Boon, N; Löwenberg, J; Singhal, N; Verliefde, A R D

    2016-02-01

    This study investigated organic micropollutant (OMP) biodegradation rates in laboratory-scale soil columns simulating river bank filtration (RBF) processes. The dosed OMP mixture consisted of 11 pharmaceuticals, 6 herbicides, 2 insecticides and 1 solvent. Columns were filled with soil from a RBF site and were fed with four different organic carbon fractions (hydrophilic, hydrophobic, transphilic and river water organic matter (RWOM)). Additionally, the effect of a short-term OMP/dissolved organic carbon (DOC) shock-load (e.g. quadrupling the OMP concentrations and doubling the DOC concentration) on OMP biodegradation rates was investigated to assess the resilience of RBF systems. The results obtained in this study imply that - in contrast to what is observed for managed aquifer recharge systems operating on wastewater effluent - OMP biodegradation rates are not affected by the type of organic carbon fraction fed to the soil column, in case of stable operation. No effect of a short-term DOC shock-load on OMP biodegradation rates between the different organic carbon fractions was observed. This means that the RBF site simulated in this study is resilient towards transient higher DOC concentrations in the river water. However, a temporary OMP shock-load affected OMP biodegradation rates observed for the columns fed with the river water organic matter (RWOM) and the hydrophilic fraction of the river water organic matter. These different biodegradation rates did not correlate with any of the parameters investigated in this study (cellular adenosine triphosphate (cATP), DOC removal, specific ultraviolet absorbance (SUVA), richness/evenness of the soil microbial population or OMP category (hydrophobicity/charge).

  12. Effects of water diversion from Yangtze River to Taihu Lake on hydrodynamic regulation of Taihu Lake%引江济太调水工程对太湖水动力的调控效果

    Institute of Scientific and Technical Information of China (English)

    郝文彬; 唐春燕; 滑磊; ACHARYA Kumud

    2012-01-01

    为研究引江济太调水工程对太湖水动力调控所产生的效果,采用数学模型对其水动力进行模拟.利用环境流体动力学模型(EFDC模型),以湖体水龄(描述湖泊水体交换速率的参数)为研究 对象,系统地研究引江济太调水工程对太湖水动力的调控情况.结果表明:(a)引江济太调水工程对太湖湖体水动力过程的作用效果很大程度上取决于风速、风向以及出入湖的流量;(b)太湖湖体水龄的分布具有很强的时空异质性,夏天的平均水龄约为130 d,其他季节的平均水龄约为230 d;(c)太湖地区夏天的主导风向——东南风能够促进东部湖区(无锡、苏州水源地所在地)和梅梁湾湖区(太湖重污染区)的水交换,改善水体运动条件;(d)望虞河入湖的最经济调水流量为100m3/s.%To study the effects of a water diversion project from the Yangtze River to Taihu Lake on the hydrodynamic regulation of Taihu Lake, mathematical models were used to simulate the hydrodynamic process. With the water age of the lake being the research focus, the hydrodynamic regulation of Taihu Lake by the project was systematically studied using the environmental fluid dynamics code (EFDC) model. The results show the following: (a) The effects of water diversion from the Yangtze River to Taihu Lake on the hydrodynamic process in Taihu Lake were mainly determined by wind velocity, wind direction, and inflow of the lake, (b) The water age of Taihu Lake presented significant spatial and temporal heterogeneity, with a mean water age of approximately 130 days in the summer and 230 days in other seasons, ? The dominant southeastly wind of the summer greatly enhanced the transport of the transferred water into the eastern lake area (the drinking water source area of Wuxi and Suzhou cities) and Meiliang Bay (a seriously polluted area of Taihu Lake), and improved water movement conditions in these areas, (d) The most efficient discharge of the

  13. The taxonomic diversity of fish community in the coastal waters of Xiamen%厦门海域鱼类群落分类学多样性的研究

    Institute of Scientific and Technical Information of China (English)

    黄良敏; 谢仰杰; 李军; 张雅芝; 王家樵

    2013-01-01

    根据厦门海域鱼类种类组成历史资料和调查资料,系统整理了厦门海域的鱼类总名录和现有名录,并应用分类学等级多样性指数和分类差异变异指数分析了厦门海域鱼类群落分类学多样性的时空变化.结果表明:厦门海域有记录鱼类共649种;现有鱼类有331种,隶属2纲22目90科181属,其中软骨鱼纲共5目9科9属15种,辐鳍鱼纲共17目81科172属316种.厦门海域鱼类总名录的等级多样性指数△+和分类差异变异指数(A)+分别为79.267和220.96;现有鱼类群落分类多样性指数△+和分类差异指数(A)+分别为77.504和245.34.分类多样性指数△+在冬、春季较高,秋季次之,而夏季最低;而分类差异指数(A)+夏季较高,秋季次之,冬春季较低.秋季和冬季鱼类组成的相似度最高,其次为夏季,最后为春季.与历史总名录相比,厦门海域的现有鱼类群落分类学范围较小,生态幅变窄,群落稳定性较差.%Based on literature and survey data of fish composition collected by bottom trawl investigation from 2006 to 2007 in Xiamen coastal waters, the fish fauna was set up, fish community and the taxonomic diversity and distinctness by using taxonomic diversity △+ and taxonomic distinctness △+ were analyzed. The results show that: there were 649 species of fishes recorded in Xiamen coastal waters. 331 species of fishes were available at present, belonging to 2 classes, 22 orders, 90 families and 181 genera, as for the Chondrichthyes fishes were composed of 5 orders, 9 families, 9 genera and 15 species, while the Actinopterygii fishes were composed of 17 orders, 81 families, 172 genera and 316 species. The taxonomic diversity △+ and taxonomic distinctness △+ of the fish community master list in Xiamen coastal waters were 79. 267 and 220. 96, 77. 504 and 245. 34 at present, respectively. The taxonomic diversity △+ in winter and spring was higher than summer and autumn, and it was lowest in summer

  14. Review of Arapaho NWR Diversion Reconstruction

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A summary of the issues and suggestions for each structure for the Diversion Reconstruction Project at the Arapaho National Wildlife Refuge after inspection by Water...

  15. 浅谈负压罐引水装置的设计和应用%Design and application of the negative pressure tank water diversion device

    Institute of Scientific and Technical Information of China (English)

    张群涛

    2015-01-01

    The negative pressure tank is a kind of water equipment, through the analysis of the working principle of the vacuum tank, put forward the design key points of negative pressure tank, to solve practical problems in engineering.%负压罐是一种水泵引水设备,通过对负压罐工作原理的分析,提出负压罐的设计要点,解决工程实际中出现的问题。

  16. Baseline Assessment of Mesophotic Reefs of the Vitória-Trindade Seamount Chain Based on Water Quality, Microbial Diversity, Benthic Cover and Fish Biomass Data

    Science.gov (United States)

    Meirelles, Pedro M.; Amado-Filho, Gilberto M.; Pereira-Filho, Guilherme H.; Pinheiro, Hudson T.; de Moura, Rodrigo L.; Joyeux, Jean-Christophe; Mazzei, Eric F.; Bastos, Alex C.; Edwards, Robert A.; Dinsdale, Elizabeth; Paranhos, Rodolfo; Santos, Eidy O.; Iida, Tetsuya; Gotoh, Kazuyoshi; Nakamura, Shota; Sawabe, Tomoo; Rezende, Carlos E.; Gadelha, Luiz M. R.; Francini-Filho, Ronaldo B.; Thompson, Cristiane; Thompson, Fabiano L.

    2015-01-01

    Seamounts are considered important sources of biodiversity and minerals. However, their biodiversity and health status are not well understood; therefore, potential conservation problems are unknown. The mesophotic reefs of the Vitória-Trindade Seamount Chain (VTC) were investigated via benthic community and fish surveys, metagenomic and water chemistry analyses, and water microbial abundance estimations. The VTC is a mosaic of reef systems and includes fleshy algae dominated rhodolith beds, crustose coralline algae (CCA) reefs, and turf algae dominated rocky reefs of varying health levels. Macro-carnivores and larger fish presented higher biomass at the CCA reefs (4.4 kg per frame) than in the rhodolith beds and rocky reefs (0.0 to 0.1 kg per frame). A larger number of metagenomic sequences identified as primary producers (e.g., Chlorophyta and Streptophyta) were found at the CCA reefs. However, the rocky reefs contained more diseased corals (>90%) than the CCA reefs (~40%) and rhodolith beds (~10%). Metagenomic analyses indicated a heterotrophic and fast-growing microbiome in rocky reef corals that may possibly lead to unhealthy conditions possibly enhanced by environmental features (e.g. light stress and high loads of labile dissolved organic carbon). VTC mounts represent important hotspots of biodiversity that deserve further conservation actions. PMID:26090804

  17. Baseline Assessment of Mesophotic Reefs of the Vitoria-Trindade Seamount Chain Based on Water Quality, Microbial Diversity, Benthic Cover and Fish Biomass Data.

    Directory of Open Access Journals (Sweden)

    Pedro M Meirelles

    Full Text Available Seamounts are considered important sources of biodiversity and minerals. However, their biodiversity and health status are not well understood; therefore, potential conservation problems are unknown. The mesophotic reefs of the Vitória-Trindade Seamount Chain (VTC were investigated via benthic community and fish surveys, metagenomic and water chemistry analyses, and water microbial abundance estimations. The VTC is a mosaic of reef systems and includes fleshy algae dominated rhodolith beds, crustose coralline algae (CCA reefs, and turf algae dominated rocky reefs of varying health levels. Macro-carnivores and larger fish presented higher biomass at the CCA reefs (4.4 kg per frame than in the rhodolith beds and rocky reefs (0.0 to 0.1 kg per frame. A larger number of metagenomic sequences identified as primary producers (e.g., Chlorophyta and Streptophyta were found at the CCA reefs. However, the rocky reefs contained more diseased corals (>90% than the CCA reefs (~40% and rhodolith beds (~10%. Metagenomic analyses indicated a heterotrophic and fast-growing microbiome in rocky reef corals that may possibly lead to unhealthy conditions possibly enhanced by environmental features (e.g. light stress and high loads of labile dissolved organic carbon. VTC mounts represent important hotspots of biodiversity that deserve further conservation actions.

  18. Baseline Assessment of Mesophotic Reefs of the Vitória-Trindade Seamount Chain Based on Water Quality, Microbial Diversity, Benthic Cover and Fish Biomass Data.

    Science.gov (United States)

    Meirelles, Pedro M; Amado-Filho, Gilberto M; Pereira-Filho, Guilherme H; Pinheiro, Hudson T; de Moura, Rodrigo L; Joyeux, Jean-Christophe; Mazzei, Eric F; Bastos, Alex C; Edwards, Robert A; Dinsdale, Elizabeth; Paranhos, Rodolfo; Santos, Eidy O; Iida, Tetsuya; Gotoh, Kazuyoshi; Nakamura, Shota; Sawabe, Tomoo; Rezende, Carlos E; Gadelha, Luiz M R; Francini-Filho, Ronaldo B; Thompson, Cristiane; Thompson, Fabiano L

    2015-01-01

    Seamounts are considered important sources of biodiversity and minerals. However, their biodiversity and health status are not well understood; therefore, potential conservation problems are unknown. The mesophotic reefs of the Vitória-Trindade Seamount Chain (VTC) were investigated via benthic community and fish surveys, metagenomic and water chemistry analyses, and water microbial abundance estimations. The VTC is a mosaic of reef systems and includes fleshy algae dominated rhodolith beds, crustose coralline algae (CCA) reefs, and turf algae dominated rocky reefs of varying health levels. Macro-carnivores and larger fish presented higher biomass at the CCA reefs (4.4 kg per frame) than in the rhodolith beds and rocky reefs (0.0 to 0.1 kg per frame). A larger number of metagenomic sequences identified as primary producers (e.g., Chlorophyta and Streptophyta) were found at the CCA reefs. However, the rocky reefs contained more diseased corals (>90%) than the CCA reefs (~40%) and rhodolith beds (~10%). Metagenomic analyses indicated a heterotrophic and fast-growing microbiome in rocky reef corals that may possibly lead to unhealthy conditions possibly enhanced by environmental features (e.g. light stress and high loads of labile dissolved organic carbon). VTC mounts represent important hotspots of biodiversity that deserve further conservation actions.

  19. The small impact of various partial charge distributions in ground and excited state on the computational Stokes shift of 1-methyl-6-oxyquinolinium betaine in diverse water models

    Science.gov (United States)

    Heid, Esther; Harringer, Sophia; Schröder, Christian

    2016-10-01

    The influence of the partial charge distribution obtained from quantum mechanics of the solute 1-methyl-6-oxyquinolinium betaine in the ground- and first excited state on the time-dependent Stokes shift is studied via molecular dynamics computer simulation. Furthermore, the effect of the employed solvent model — here the non-polarizable SPC, TIP4P and TIP4P/2005 and the polarizable SWM4 water model — on the solvation dynamics of the system is investigated. The use of different functionals and calculation methods influences the partial charge distribution and the magnitude of the dipole moment of the solute, but not the orientation of the dipole moment. Simulations based on the calculated charge distributions show nearly the same relaxation behavior. Approximating the whole solute molecule by a dipole results in the same relaxation behavior, but lower solvation energies, indicating that the time scale of the Stokes shift does not depend on peculiarities of the solute. However, the SPC and TIP4P water models show too fast dynamics which can be ascribed to a too large diffusion coefficient and too low viscosity. The calculated diffusion coefficient and viscosity for the SWM4 and TIP4P/2005 models coincide well with experimental values and the corresponding relaxation behavior is comparable to experimental values. Furthermore we found that for a quantitative description of the Stokes shift of the applied system at least two solvation shells around the solute have to be taken into account.

  20. Training In Diversity Management

    Directory of Open Access Journals (Sweden)

    Sonja Treven

    2011-07-01

    Full Text Available The labor force all around the world is becoming increasingly diverse. Thus, organizations that can manage employee diversity effectively gain a competitive advantage. In such organizations diversity training is a necessity. Diversity training helps managers understand and value individual differences and develop strong diagnostic skills. The paper explores various approaches to training, like awareness-based and skill-based diversity training. A special attention to potential problems that may occur in the process of diversity training is given.

  1. Diversity: A Philosophical Perspective

    Directory of Open Access Journals (Sweden)

    Sahotra Sarkar

    2010-01-01

    Full Text Available In recent years, diversity, whether it be ecological, biological, cultural, or linguistic diversity, has emerged as a major cultural value. This paper analyzes whether a single concept of diversity can underwrite discussions of diversity in different disciplines. More importantly, it analyzes the normative justification for the endorsement of diversity as a goal in all contexts. It concludes that no more than a relatively trivial concept of diversity as richness is common to all contexts. Moreover, there is no universal justification for the endorsement of diversity. Arguments to justify the protection of diversity must be tailored to individual contexts.

  2. 南水北调工程水资源生态补偿理论分析基于博弈论和前景理论的视角%Theoretical Analysis of Water Resource Ecological Compensation of South-to-North Water Diversion Project:Based on the Perspective of Game Theory and Prospect Theory

    Institute of Scientific and Technical Information of China (English)

    邵毅

    2015-01-01

    Water source areas of South-to-North Water Diversion Project need regular input costs for ecological protection and lost some opportunities at the same time ,benefited areas need to pay some ecological compensation fees for water source areas .In this study ,based on the game theory and prospect theory ,the change of revenue expenditure in different periods of water source areas and benefited areas is compared and the change of their strategies is analyzed .Finally ,some countermeasures of establishing the wa‐ter resources ecological compensation mechanism for South-to-North Water Diversion Project from the aspects of the compensation standard ,compensation mode ,and so on ,are put forward .%南水北调工程水源区需要定期投入成本进行生态保护,自身也失去了部分发展机会,受水区需要对水源区支付一定的生态补偿费用。基于博弈论和前景理论,比较不同时期水源区和受水区的收益支出变化情况,分析各自策略的变化。最后从补偿标准、补偿方式等方面提出构建南水北调工程水资源生态补偿机制的几点对策建议。

  3. Selection and Installation of Large-size Butterfly Valve in Xijiang River Water Diversion Project%西江引水工程大口径蝶阀的选型和安装

    Institute of Scientific and Technical Information of China (English)

    韩勇; 黄长均; 匡科

    2012-01-01

    In order to guarantee the normal operation and supply safety of water conveyance system in Xijiang River water diversion project, large-size butterfly valves of DN3 600 were set up. According to the project practice, butterfly valve was selected based on the basic requirements of major technical performance index, type of construction, drive mechanism and manufacturing material. In order to ensure the valve installation quality, main technical points of butterfly valve installation were put forward, such as joint of valve and pipeline fittings, hoisting and welding.%为保障西江引水工程输水系统正常运行和供水安全,在系统中设置了DN3 600的大口径蝶阀.根据工程实际情况,在确定主要技术性能指标、结构形式、传动机构以及制造材料等基本要求的基础上,开展阀门选型工作.为保障阀门的安装质量,从阀门与管道附件的连接、吊装和焊接方面提出了大口径蝶阀安装的主要技术要点.

  4. Emergence of Algal Blooms: The Effects of Short-Term Variability in Water Quality on Phytoplankton Abundance, Diversity, and Community Composition in a Tidal Estuary

    Directory of Open Access Journals (Sweden)

    Todd A. Egerton

    2014-01-01

    Full Text Available Algal blooms are dynamic phenomena, often attributed to environmental parameters that vary on short timescales (e.g., hours to days. Phytoplankton monitoring programs are largely designed to examine long-term trends and interannual variability. In order to better understand and evaluate the relationships between water quality variables and the genesis of algal blooms, daily samples were collected over a 34 day period in the eutrophic Lafayette River, a tidal tributary within Chesapeake Bay’s estuarine complex, during spring 2006. During this period two distinct algal blooms occurred; the first was a cryptomonad bloom and this was followed by a bloom of the mixotrophic dinoflagellate, Gymnodinium instriatum. Chlorophyll a, nutrient concentrations, and physical and chemical parameters were measured daily along with phytoplankton abundance and community composition. While 65 phytoplankton species from eight major taxonomic groups were identified in samples and total micro- and nano-phytoplankton cell densities ranged from 5.8 × 106 to 7.8 × 107 cells L−1, during blooms, cryptomonads and G. instriatum were 91.6% and 99.0%, respectively, of the total phytoplankton biomass during blooms. The cryptomonad bloom developed following a period of rainfall and concomitant increases in inorganic nitrogen concentrations. Nitrate, nitrite and ammonium concentrations 0 to 5 days prior were positively lag-correlated with cryptomonad abundance. In contrast, the G. insriatum bloom developed during periods of low dissolved nitrogen concentrations and their abundance was negatively correlated with inorganic nitrogen concentrations.

  5. Managing Workplace Diversity

    OpenAIRE

    Harold Andrew Patrick; Vincent Raj Kumar

    2012-01-01

    Diversity management is a process intended to create and maintain a positive work environment where the similarities and differences of individuals are valued. The literature on diversity management has mostly emphasized on organization culture; its impact on diversity openness; human resource management practices; institutional environments and organizational contexts to diversity-related pressures, expectations, requ...

  6. Multiplying Forest Garden Systems with biochar based organic fertilization for high carbon accumulation, improved water storage, nutrient cycling, and increased food diversity and farm productivity

    Science.gov (United States)

    Schmidt, Hans-Peter; Pandit, Bishnu Hari; Lucht, Wolfgang; Gerten, Dieter; Kammann, Claudia

    2017-04-01

    On abandoned, erosion prone terraces in the middle hills of Nepal, 86 participating farmer families planted >25,000 mixed trees in 2015/16. Since it was convincingly demonstrated by more than 20 field trials in this region that this was the most plant-growth promoting method, all trees were planted with farmer-made organic biochar-based fertilizer. Planting pits were mulched with rice straw and were pipe irrigated from newly established water retention ponds during the 7 months of the dry season. A peer control system of farmer triads ensured an efficient maintenance of the plantations. Tree survival rate was above 80% after one year compared to below 50% on average for countrywide forestation projects over the last 30 years. In between the young Cinnamon, Moringa, Mulberry, Lemon, Michelia, Paulownia, nut and other trees, other secondary crops were cultivated such as ginger, turmeric, black beans, onions, lentils, all with organic biochar-based fertilizer and mulching. The objective of this forest garden project was to establish robust social-agronomic systems that can be multiplied from village to village for increasing soil fertility, protecting abandoned terraces from erosion, replenishing natural water resources, generating a stable income with climate-smart agriculture, as well as capturing and sequestering atmospheric carbon. The initial financing of the set-up of the forest garden systems (tree nursery, plantation, preparation of organic biochar based fertilizer, mulching materials, building of irrigation pits and pipe irrigation system, and general maintenance) was covered by carbon credits paid in advance by the international community in the form of a monthly carbon compensation subscription. All planted trees are GIS inventoried and the yearly biomass carbon uptake will be calculated as an average value of the first ten years of tree growth. The 25,000 mixed trees accumulated the equivalent of 350 t CO2 per year (10 years total C-accumulation divided by

  7. Study on deep fluid diversion in Daqing Oilfield at high water-cut stage%大庆油田高含水期深部液流转向试验研究

    Institute of Scientific and Technical Information of China (English)

    李承龙; 吴文祥

    2015-01-01

    At present,Daqing Oilfield has entered the extra high water-cut stage.With the increasing recovery percent of reserve,the effect of waterflooding becomes worse and worse because of high scattered remaining oil distribution,more watered-out wells,and serious interlay interference.Now,the conventional chemical conformance control technologies can not be used to plug deep parts in high permeability layer or large channel.Taking SⅡ1+2b formation in the western of Bei 3 block as an example,we studied the deep fluid diversion technology.A new technology for improving effect of wateflood-ing was proposed,which includes plugging water breakthrough channel and increasing the utilization of medium to low per-meability formations.The technology can provide a new way for further improving the development effect of water flooding oilfield at high water-cut stage.%大庆油田目前已进入特高含水期。随着区块采出程度的日益提高,剩余油高度分散,水淹普遍,层间矛盾较为突出,水驱效果变差。目前,常规的化学调剖方法还很不完善,不能够对高渗层或大孔道深部进行封堵。以北三区西部SⅡ1+2b层为例,对深部液流转向技术进行研究,并且提出封堵水窜通道,增加中低渗透层利用率,改善水驱效果的新技术,为高含水油田进一步改善水驱开发效果提供新的途径。

  8. 南水北调中线总干渠水热环境分析%Analysis of water-thermal environment of main canal of Middle Route Project of South-to-North Water Diversion

    Institute of Scientific and Technical Information of China (English)

    闫弈博; 黄会勇; 冷星火; 王长德

    2014-01-01

    水体热量总收支的确定是水渠冰情数值模拟的关键,根据热力守恒方程建立了河渠敞流期热量收支方程。以南水北调中线汤河-惠南庄段干渠为例,通过对干渠沿线6个气象站1986~2005共20 a资料的统计分析,计算了太阳辐射水-气温差、风速等水热环境因素对典型输水渠道水体热量收支的影响。指出太阳净辐射量、气温、风速、相对湿度是明渠冬季热力学及冰情模拟必需要考虑的气象环境资料,而总云量影响相对较小。%The heat budget equation of non-ice cover channel is established based on conservation equation of heat quantity. Taking the main canal section from Tanghe to Huinanzhuang as an example, we carry out a statistical analysis for the meteorologi-cal data of 20 years collected from 6 meteorological stations along the channel, and the influences of water-thermal environment factors such as solar radiation, temperature differences of water-air, wind velocity on water body heat budget is calculated. It is concluded that the factors of solar radiation, air temperature, wind velocity as well as relative moisture are the essential meteoro-logical data for ice regime simulation and thermodynamics study of channel in winter, however the cloud cover has relative smaller influences on the water heat budget.

  9. The diversity and extracellular enzymatic activities of yeasts isolated from water tanks of Vriesea minarum, an endangered bromeliad species in Brazil, and the description of Occultifur brasiliensis f.a., sp. nov.

    Science.gov (United States)

    Gomes, Fátima C O; Safar, Silvana V B; Marques, Andrea R; Medeiros, Adriana O; Santos, Ana Raquel O; Carvalho, Cláudia; Lachance, Marc-André; Sampaio, José Paulo; Rosa, Carlos A

    2015-02-01

    The diversity of yeast species collected from the bromeliad tanks of Vriesea minarum, an endangered bromeliad species, and their ability to produce extracellular enzymes were studied. Water samples were collected from 30 tanks of bromeliads living in a rupestrian field site located at Serrada Piedade, Minas Gerais state, Brazil, during both the dry and rainy seasons. Thirty-six species were isolated, representing 22 basidiomycetous and 14 ascomycetous species. Occultifur sp., Cryptococcus podzolicus and Cryptococcus sp. 1 were the prevalent basidiomycetous species. The yeast-like fungus from the order Myriangiales, Candida silvae and Aureobasidium pullulans were the most frequent ascomycetous species. The diversity of the yeast communities obtained between seasons was not significantly different, but the yeast composition per bromeliad was different between seasons. These results suggest that there is significant spatial heterogeneity in the composition of populations of the yeast communities within bromeliad tanks, independent of the season. Among the 352 yeast isolates tested, 282 showed at least one enzymatic activity. Protease activity was the most widely expressed extracellular enzymatic activity, followed by xylanase, amylase, pectinase and cellulase activities. These enzymes may increase the carbon and nitrogen availability for the microbial food web in the bromeliad tank of V. minarum. Sequence analyses revealed the existence of 10 new species, indicating that bromeliad tanks are important sources of new yeasts. The novel species Occultifur brasiliensis, f.a., sp. nov., is proposed to accommodate the most frequently isolated yeast associated with V. minarum. The type strain of O. brasiliensis, f.a., sp. nov. is UFMG-CM-Y375(T) (= CBS 12687(T)). The Mycobank number is MB 809816.

  10. Hiberarchy of Requi rement Analysis on Diversity Actuation System for Advanced Pressurized Water Reactor Nuclear Power Plant%先进压水堆核电厂多样性驱动系统需求分析结构

    Institute of Scientific and Technical Information of China (English)

    刘爱国; 江辉; 孙伟; 田亚杰; 朱学农

    2014-01-01

    核电厂数字化应用需应对软件可能的共因失效所带来的问题。多样性驱动系统(DAS )用于数字化保护系统软件共因失效(CCF)时缓解和抵御核电厂发生设计基准事件的后果。本研究在核电厂纵深防御与多样性原则的指导下,对先进压水堆核电厂的多样性驱动系统需求进行分析研究,阐明了先进压水堆核电厂多样性驱动系统的设计特性、过程、依据、方法及系统结构。%The digital systems applied to nuclear power plants need to address the prob‐lems created by common‐cause failure (CCF) of the software .The diversity actuation system (DAS) can resist and relieve accident consequence for nuclear power plant ,when postulated CCF of reactor protection system and design‐basis event take place at the same time .According to the defense‐in‐depth and diversity principles of nuclear power plant ,the requirement analysis of DAS for pressurized water reactor was researched . The design characteristic property ,design process ,design basis ,design methods and system structure of DAS were systematically expounded .

  11. 南水北调中线湍河渡槽槽身施工方案研究%Construction scheme of Tuanhe aqueduct of Middle Route Project of South-to-North Water Diversion

    Institute of Scientific and Technical Information of China (English)

    简兴昌; 梁仁强; 杨谢芸

    2014-01-01

    To meet the design requirements of quality and construction schedule of Tuanhe aqueduct of South- to-North Wa-ter Diversion, the paper compares the construction schemes and technologies by two methods of full scaffold and aqueduct fabrica-tion machine according to engineering and structural properties of the aqueduct. With the tech-economic comparison from five aspects of construction quality, period, cost, safety and construction diversion, the optimized construction scheme by aqueduct fabrication machine with 40m width of span and 1600t weight is selected and successfully applied in engineering practice. The project was totally completed on September 28, 2013. The successful experience has significant promoting effect to the construc-tion equipment, technology and techniques of large-scale aqueducts in China.%为保证南水北调中线湍河渡槽的施工质量和工期满足设计要求,结合渡槽的工程特性及槽身结构特点,对槽身满堂支架法及造槽机法的施工方案及施工工艺进行了研究。经施工质量、工期、造价、安全、施工导流等方面的技术经济比较,优选出40 m跨1600 t重的造槽机施工方案,并成功应用于工程实践。工程于2013年9月28日完成全部施工,其成功经验,对我国大型渡槽施工设备、施工工艺、施工技术具有巨大推动作用。

  12. Diversity in Organizations

    OpenAIRE

    Mello, Antonio S; Ruckes, Martin

    2001-01-01

    This Paper develops a theory of diversity in work groups within organizations. Diversity is determined by the group members' dfferences in backgrounds. Diverse teams possess more information than homogeneous ones. If beliefs and preferences are expressed openly, diverse teams can reach better decisions. However, due to their members' heterogeneous backgrounds diverse teams are more prone to conflict. The Paper shows that the relative performance of heterogeneous and homogeneous groups depends...

  13. New Ideas on Water Transfer and Pollution Treatment Based on Artificial Diversion in Taihu Lake%基于人工导流的太湖调水清污新思路

    Institute of Scientific and Technical Information of China (English)

    陈凯麒; 祁昌军; 李巍; 陶洁

    2014-01-01

    The ecological treatment measures and methods in the Taihu Lake were analyzed and summarized, andthe numerical simulation method adopted to establish a two-dimensional plane hydrodynamic and water qualitymodel.According the simulated results of different dominant wind direction combinations of southeast, northwestand northeast, the flow field variation regularities and streamline variation forms of the Taihu Lake were analyzed.Under the new idea of reducing invalid closed circulation system and improving the contaminant exchange ratethrough artificial diversion, the construction of diversion dike with the combination of sludge dredging, waterwaydredging and landscaping engineering in the Taihu Lake was proposed, which could barrier the invalid endless loopsystem forced by wind, organize and guide the water flow, promote water cycle, and then improve the clean-upeffective significantly.The results show that it plays an obvious role in promoting contaminant exchange rate of theTaihu Lake.Among the five diversion dike schemes, Scheme 5 is the optimal one with most obvious improvement ofthe contaminant exchange rate.%分析总结了太湖生态治理措施和方法,利用数值模拟方法建立太湖平面二维水动力、水质模型,根据东南风、西北风和东北风不同主导风组合下的计算结果,分析太湖流场变化规律和太湖湖区流线变化形态。基于人工导流,减少太湖无效闭合环流,提高太湖污染物置换率的考虑,提出一种新思路,在太湖内结合清淤、航道疏浚及景观美化工程建设导流堤,阻隔太湖在风力作用下形成无效的“死”循环系统,有组织地引导、控制水体流动,从而促进湖体的有序水循环,大幅度、高效地改善太湖调水清污效果。结果表明,在太湖配合引水工程修建导流堤,对促进太湖污染物置换有明显的改善作用,与原始工况相比,导流堤方案五对太湖污染物置换率的改

  14. 引黄工程水源地年径流量长期演变规律研究%Study on long-term evolution law of annual runoff in water source of Yellow river diversion project

    Institute of Scientific and Technical Information of China (English)

    徐聪; 冯民权

    2014-01-01

    By use of Kendall trend test method , R/S analysis method , run-length analysis method and Markov process analysis method , the paper analyzed the long-term evolution law of annual runoff at the water source of central Yellow River diversion project .The annual runoff timing at Hequ station of the Yellow River showed a significant decreasing trend during the whole period 1978 to 2010 .According to the result,the runoff will continue to show a more significant decreasing trend in the future .The occur-rence probability of continuous multi-annual high flow state , normal flow state and low flow state de-creased with the increase of consecutive years .In the long-term evolution process of high and low state , the reproduce time of partial low flow year is the shortest and the reproduce time of partial high flow year is the longest .The annual runoff at water source of the central Yellow River diversion project will show a more significant decreasing trend in the future;In the process of high and low evolution of annual runoff , it is more likely to appear low flow year .The study can provide a scientific basis for the sustainable devel-opment and utilization of water resources on the Yellow River and the regulation of supply and demand of the central Yellow River diversion project .%利用Kendall秩次相关检验法、R/S分析法、游程分析法和马尔可夫过程分析法对中部引黄工程水源地年径流量长期演变规律进行分析。黄河河曲站年径流量时序在1978-2010年整个时段内呈现出显著的减少趋势,并且可以预测出未来河曲站的年径流量将继续呈较显著减少趋势;河曲站连丰、连平和连枯状态的出现概率都随连续年数的增加而减小;在长期丰枯演化过程中,偏枯年的重现时间最短,偏丰年的重现时间最长。中部引黄工程水源地年径流量未来呈较显著的减少趋势;在年径流长期丰枯演化过程中,出现偏枯年的可能性

  15. Diversity and Distribution of Tufa Water Algae in Huanglong National Scenic Spot%黄龙钙华水体藻多样性及分布规律研究

    Institute of Scientific and Technical Information of China (English)

    刘明学; 杨智; 郭玉婷; 唐淑; 胡韧; 董发勤; 孙仕勇; 安德军; 易伟; 王晓娟; 熊星; 陈东亮; 周星霞

    2013-01-01

    Species diversity and distribution of tufa water algae in Huanglong National Scenic Spot was investigated. Results showed that there were 53 species, belonging to 23 genera and 5 divisions. Tufa algae community in the Spot is a community that Bacillariophyta become dominant species, secondly dominated by Chlorophyta, Xanthophyta, Cyanophyta, Euglenophyta and Chrysophyta are the least. Chlorella is the dominant species at the month of spring in spring season, while Bacillariophyta is the dominant species in tufa water in summer and autumn. Tufa water algae numbers show the maximum at the mouth of spring and decrease with degrade of altitude in spring season, while the maximum numbers of algae appear at Jinshapudi tufa beach in autumn. Analysis indicated that Margalef index is from 0.083 to 0.667, Shannon-winner index is from 0.191 to 1.99, Pielou evenness index is from 0.276 to 1.000. Results may suggest that the diversity and distribution of tufa water algae from the Spot are affected by environmental factors such as season, temperature and amount of water as well as geographical factors such as altitude, tufa beach, pool and showed periodic succession.%对黄龙钙华水体藻种类、分布规律及多样性进行了研究,共鉴定出23属53种淡水藻类,分属5门.黄龙钙华水体藻类以硅藻占绝对优势,绿藻、黄藻门、蓝藻门次之,裸藻门、金藻门最少.从季节交替变化来看,春季小球藻最多,夏秋季节硅藻最多;从分布规律来看,夏季以海拔最高的泉眼处藻类最多,沿海拔降低藻类数量递减;秋季以钙华滩流群处藻类最盛.多样性分析结果表明,黄龙水体钙华藻类的物种丰富度指数dmax在0.083~0.667之间,多样性指数H在0.191~1.99之间,均匀度e在0.276~1.000之间.结果表明黄龙钙华水体藻类受到季节、温度、水量等环境因数和海拔、钙华滩、彩池等地理因素影响表现出现种群的周期演替.

  16. 43 CFR 418.18 - Diversions at Derby Dam.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Diversions at Derby Dam. 418.18 Section... Operations and Management § 418.18 Diversions at Derby Dam. (a) Diversions of Truckee River water at Derby Dam must be managed to maintain minimum terminal flow to Lahontan Reservoir or the Carson River...

  17. Research on Method of Long Water Diversion Line-Selecting Based on GIS%基于GIS的长大引水线路优选的方法研究

    Institute of Scientific and Technical Information of China (English)

    余国; 谢谟文; 王立伟

    2014-01-01

    本文提出了基于GIS的长大引水线路优选的方法研究。在对影响长大引水线路选线方案的各因素进行分析和调查基础上,选取4个一级指标、11个二级指标构建综合评价指标体系;对各个影响评价因子进行栅格化,并划分为5个等级,分别赋值1到5,建立各个选线因子的对线路影响程度的分级栅格模型;然后通过层次分析法建立层次关系,构造阶层结构,建立判断矩阵,来确定各个影响评价因子的综合指标权重,建立综合评判优选栅格模型。利用该模型对云南滇中引水工程香炉山段4条备选线路方案进行评价,得出备选方案的总分和平均分,从而确定第三方案为最优方案,为实际工程建设提供了决策依据。%This thesis deals with the study of methods for long water diversion route which is based on GIS. Based on the analysis and investigation of factors affecting the long water diversion location, Select four first-level indicators, eleven second-level indicators to build a comprehensive evolution index system, and rasterize all the factors that will have an effect on the evolution, then divide then into 5 grades, assign them one to five respectively. Establish a hierarchical gird model of the inference which all the linear factors will have on the line. and then, establish a hierarchical relationship through the hierachy analytic process. By constructing a class structure and establishing a estimate matrix, one can determine the comprehensive index weight of all the influential factors, and set up the comprehensive evolution optimal grid model.

  18. Diversity and abundance of ammonia-oxidizing

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; van Bleijswijk, J.D.L.; Witte, H.; van Duyl, F.C.

    2013-01-01

    We analysed the diversity and abundance of ammonia-oxidizing Archaea (AOA) and Bacteria (AOB) in the shallow warm-water sponge Halisarca caerulea and the deep cold-water sponges Higginsia thielei and Nodastrella nodastrella. The abundance of AOA and AOB was analysed using catalyzed reporter

  19. Diversity and abundance of ammonia-oxidizing

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; van Bleijswijk, J.D.L.; Witte, H.; van Duyl, F.C.

    2013-01-01

    We analysed the diversity and abundance of ammonia-oxidizing Archaea (AOA) and Bacteria (AOB) in the shallow warm-water sponge Halisarca caerulea and the deep cold-water sponges Higginsia thielei and Nodastrella nodastrella. The abundance of AOA and AOB was analysed using catalyzed reporter depositi

  20. Diversity and abundance of ammonia-oxidizing

    NARCIS (Netherlands)

    Cardoso, J.F.M.F.; van Bleijswijk, J.D.L.; Witte, H.; van Duyl, F.C.

    2013-01-01

    We analysed the diversity and abundance of ammonia-oxidizing Archaea (AOA) and Bacteria (AOB) in the shallow warm-water sponge Halisarca caerulea and the deep cold-water sponges Higginsia thielei and Nodastrella nodastrella. The abundance of AOA and AOB was analysed using catalyzed reporter depositi

  1. 千岛湖配水工程对钱塘江河口盐水入侵影响%Effects of Qiandao Lake water diversion project on Qiantang River estuary saltwater intrusion

    Institute of Scientific and Technical Information of China (English)

    张舒羽; 周维; 史英标

    2016-01-01

    Qiandao Lake water diversion project will change the runoff process of the Fuchun reservoir and the salini-ty of Qiantang River estuary. A two-dimensional numerical salinity model which including tidal bore′s action is estab-lished. Based on tide and salinity testing, the distance of saltwater intrusion and the exceeding period of important wa-ter inlets caused by the project are calculated. Results showed that, it will be significantly effected in the low flow year by the current scheduling scheme, the distance of saltwater intrusion is increased 3 700 meters and time available for water inlets time along the river is shorten 0. 2~3. 6 days, but it is little effected in normal and high flow year. In or-der to reduce the influence of the salt water intrusion which happened due to the project in low flow year, a reservoir optimal operation is necessary.%杭州市第二水源千岛湖配水工程(简称配水工程)的实施将引起富春江水库下泄流量及过程改变,从而对钱塘江河口盐水入侵产生影响。建立考虑涌潮作用的二维盐度数值模型,在验证钱塘江河口潮位和盐度的基础上,预测配水工程实施对河口盐水入侵距离和重要取水口含氯度超标时间的影响。研究表明:配水工程实施后,上游富春江水库若按现状调度方案,对枯水年影响大,咸水上溯距离增加3.7 km,沿岸取水口的可取水时间缩短0.2~3.6 d,丰、平水年盐水入侵和引水前相当;通过水库的优化调度,可基本消除枯水年引水造成的盐水入侵影响。为减少配水工程实施的盐水入侵影响,采用水库的优化调度模式是必要的。

  2. Diversity as Polyphony

    DEFF Research Database (Denmark)

    Trittin, Hannah; Schoeneborn, Dennis

    2017-01-01

    In this paper, we propose reconceptualizing diversity management from a communication-centered perspective. We base our proposal on the observation that the literature on diversity management, both in the instrumental and critical traditions, is primarily concerned with fostering the diversity of...... of diversity management as dynamic processes of voice articulation and mediation......In this paper, we propose reconceptualizing diversity management from a communication-centered perspective. We base our proposal on the observation that the literature on diversity management, both in the instrumental and critical traditions, is primarily concerned with fostering the diversity...... as the range of individual opinions and societal discourses that get expressed and can find resonance in organizational settings. We contribute to the literature on diversity management by moving away from a focus on individual-bound and inalterable criteria of diversity and toward a reconceptualization...

  3. Does staff diversity imply openness to diversity?

    DEFF Research Database (Denmark)

    Lauring, Jakob; Selmer, Jan

    2013-01-01

    university departments in Denmark. The authors set out to investigate the relationship between different types of staff diversity and openness to diversity in terms of linguistic, visible, value, and informational heterogeneity. Design/methodology/approach – This study uses responses from 489 staff members...

  4. CERN Diversity Newsletter - April 2017

    CERN Document Server

    AUTHOR|(CDS)2069427; Koutava, Ioanna; CERN. Geneva. HR Department

    2017-01-01

    The CERN Diversity Newsletter, informing on recent and ongoing diversity activities, and interesting reads, videos and other links related to diversity. Subscribe here: https://diversity.web.cern.ch/2015/07/subscribe-diversity-newsletter

  5. CERN Diversity Newsletter - March 2016

    CERN Document Server

    Kaltenhauser, Kristin; CERN. Geneva. HR Department

    2016-01-01

    Quarterly CERN Diversity Newsletter, informing on recent and ongoing diversity activities, and interesting reads, videos and other links related to diversity. Subscribe here: https://diversity.web.cern.ch/2015/07/subscribe-diversity-newsletter

  6. CERN Diversity Newsletter - November 2015

    CERN Document Server

    Kaltenhauser, Kristin; CERN. Geneva. HR Department

    2015-01-01

    Quarterly CERN Diversity Newsletter, informing on recent and ongoing diversity activities, and interesting reads, videos and other links related to diversity. Subscribe here: https://diversity.web.cern.ch/2015/07/subscribe-diversity-newsletter

  7. CERN Diversity Newsletter - September 2016

    CERN Document Server

    Guinot, Genevieve

    2016-01-01

    Quarterly CERN Diversity Newsletter, informing on recent and ongoing diversity activities, and interesting reads, videos and other links related to diversity. Subscribe here: https://diversity.web.cern.ch/2015/07/subscribe-diversity-newsletter

  8. 利用PCR-DGGE分析海水浴场细菌多样性%Analysis of bacterial community diversity of marine bathing beach water by PCR-DGGE

    Institute of Scientific and Technical Information of China (English)

    李江宇; 樊景凤; 穆贵强; 李洪波; 韩俊丽; 高小玉

    2013-01-01

    2011年5月,于大连星海浴场采集海水样品,采用PCR-DGGE技术分析其细菌多样性.分析结果表明:近排污口处水样细菌群落多样性较远排污口处高,细菌类群主要由厚壁菌门(53%)、变形菌门(26.7% ~ 29.4%)和拟杆菌门(17.6% ~20%)组成,其中可培养细菌类群序列占总细菌类群序列的64.7%~66.7%,离排污口较远处水样中可培养细菌类群中乳酸杆菌所占总测序序列的比例最高(13.3%),而近排污口处为弓形杆菌(11.8%)和梭菌(11.8%)最高.浴场中拟杆菌和嗜低温弓形菌(Arcobacter cryaerophilus)为优势菌,其中嗜低温弓形菌为致病菌,其他致病性细菌没有被检测到;由于DGGE有一定的基因含量检测限度,所以表明嗜低温弓形菌较其他可能存在于浴场中的致病菌的丰度高.%The bacterial community diversity of Xinghai Bathing Beach was analysed by PCR-DGGE in Dalian in May,2011.The bacterial diversity of water samples nearer from a off-shore sewage outfall was higher than other locations.Three bacteria phyla Firmicutes (53 %)、Proteobacteria (26.7% ~ 29.4%) and Bacteroidetes (17.6% ~ 20%) make up the majority of the predominant bacteria structure,Lactobacillus spp.(13.3%) in the water with a longer distance from the sewage outfall and Arcobacter spp.(11.8%) and Clostridium spp.(11.8%) in the water with a shorter distance from the sewage outfall were the predominant phyla of the cultured bacterial phyla which were 64.7% ~ 66.7% in the total bacterial phyla.Bacteroides sp.of the uncultured bacterial phyla and Arcobacter cryaerophilus of the cultured bacterial phyla were the predominant bacterial population,Arcobacter cryaerophilus of which was detected as a kind of pathogenic bacterium,the other pathogenic bacteria were not detected,which suggested that Arcobacter cryaerophilus may have a great richness than other pathogenic bacterium which possibly survived but not detected in the

  9. 台湾海峡及其邻近海域黄鲫群体遗传多样性研究%THE GENETIC DIVERSITY OFSETIPINNA TENUIFILISIN TAIWAN STRAIT AND THE ADJACENT WATERS

    Institute of Scientific and Technical Information of China (English)

    张丽艳; 张跃平; 周治东; 李渊; 林龙山; 宋普庆

    2015-01-01

    本研究对采自台湾海峡及其邻近海域4个群体(宁德、平潭、厦门和漳浦)的黄鲫样品进行线粒体DNA控制区基因片段扩增,并基于此片段检测该海域黄鲫群体的遗传多样性和遗传结构。结果显示,控制区前半段存在4—7次39 bp的重复单元,5次重复所占比例最高,并随着从北向南有逐渐降低的趋势。4个黄鲫群体呈现出高的单倍型多样度和低的核苷酸多样度,遗传多样性处于较高水平。邻接关系树和单倍型网络图中并未检测到与地理群体相对应的谱系结构;基因流和确切 P检验结果显示4个黄鲫群体间可进行随机交配; AMOVA和Fst分析结果显示遗传变异主要来自于黄鲫群体内,群体间遗传分化微弱,无显著群体遗传结构。核苷酸不配对分布和中性检验结果均显示黄鲫经历了近期的群体扩张事件,推测扩张时间大约在2.5万—4.9万年前,属于更新世晚期。虽然该海域黄鲫的遗传多样性较高,但其资源量已经出现衰退的迹象,应加强相应的渔业管理措施,合理开发和利用黄鲫资源做到可持续发展。%In this study, we investigated the genetic diversity and genetic structure ofSetipinna tenuifilis populations in the Taiwan Strait and its adjacent waters. We amplified and sequenced the mitochondrial DNA control region segments by using PCR from 96 individuals of four populations (Ningde, Pingtan, Xiamen and Zhangpu). A 39-bp tandem copy was found at the 5 end of the segment and the numbers of polymorphic tandem copies were 4—7 detected in four popu-lations. The most frequency number of copies was five in all four populations, and the number decreased from northto south. High genetic diversity was detected among the four populations, along with the high haplotype diversity and the low nucleotide diversity. We did not observe the genealogical structure corresponding to sampling locations in the neighbor-joining tree and the

  10. Riverside morphological response to pulsed sediment diversions

    Science.gov (United States)

    Meselhe, Ehab A.; Sadid, Kazi M.; Allison, Mead A.

    2016-10-01

    Sediment diversions deliver sediment and fresh water from rivers to surrounding wetland areas as a strategy to build and sustain coastal wetland areas. Numerical modeling of the lower Mississippi River, USA, coupled with detailed field observations are used to provide quantitative information about the morphodynamic behavior of river channels in response to diverting large quantities of water and sediment. This study suggests that reduction in river stream power caused by the extraction of significant amounts of water discharge results in river channel aggradation in the vicinity and downstream of diversions. The aggradation quantities depend on the diversion sand capture efficiency and the diverted water discharge relative to the main river discharge. Additional factors observed to influence the sand capture efficiency include the invert elevation of the diversion intake, placement of the diversion intake on top of a lateral or point bars, and the local degree of the river channel curvature. Notably, the capture efficiency of fine material (silt and clay), to a large degree, is not site specific and is rather influenced by the timing of the diversion structure operations relative to the incoming fine-material hydrograph.

  11. Intersectionality, Diversity and Gender

    DEFF Research Database (Denmark)

    Siim, Birte; Agustin, Lise Rolandsen

    2016-01-01

    In the discourses of Danish politicians on ethno-national diversity and integration, the notion of diversity is gendered, especially the articulation of the ‘working woman’ and her labor market participation. Equality, diversity and gender are, thus, intertwined in political, discursive construct......In the discourses of Danish politicians on ethno-national diversity and integration, the notion of diversity is gendered, especially the articulation of the ‘working woman’ and her labor market participation. Equality, diversity and gender are, thus, intertwined in political, discursive...

  12. Application of ice-block cable in the water diversion from Yellow River in winter%拦冰索在冬季引黄输水中的应用

    Institute of Scientific and Technical Information of China (English)

    高学飞; 孟国强

    2015-01-01

    The river ice flood has the swelling pressure and impact force on the buildings, it will destroyed the structure when the pressure and impact force more than the strength of the building itself. Due to the river freezing , the current speed fell and flow rate decreased, influence the discharge capacity, even the river ice jams and cut off the flow. This pa-per analyzes the application of ice-block cable in the water diversion from Yellow River in winter respectively from the as-pects of location, layout, function, observation and analysis.%河流结冰产生的冰凌对建筑物的膨胀压力及流冰对建筑物的撞击力,都因超过建筑物本身的强度而发生破坏。同时,冰凌也会给河道引水造成困难。常见的现象是河道因结冰而使流速减缓,流量降低,影响过水能力,甚至河道被冰塞堵塞,而断绝水流。该文从拦冰索选址、布设、作用、观测与分析几个方面入手,对在冬季引黄输水中的应用进行了分析。

  13. Study on the Insurance Rate of Large-scale Water Diversion Project Based on AHP Method%基于AHP法的大型调水工程保险费率研究

    Institute of Scientific and Technical Information of China (English)

    张科举; 赵旺; 刘渊

    2015-01-01

    本文将层次分析法(AHP法)应用在大型调水工程风险评估中,在比较国内外保险费率确定方法的基础上对我国普遍采用的最大可能损失法加权改进来计算费率,并运用组织风险来调整保险的费率,试图为大型调水工程风险在识别和评估的基础上研究工程保险费率提供一种新的思路和方法。%In this paper, the analytic hierarchy process (AHP) method is applied in the risk evaluation of large-scale water diversion project. Based on the comparison of the method of determining the insurance rate at home and abroad, the commonly used maximum possible loss method is improved by weighting to calculate the rate, and organizational risk is used to adjust the insurance rates, trying to provide a new idea and method for the research of the engineering insurance rate on the basis of risk reorganization and evaluation.

  14. Branding water.

    Science.gov (United States)

    Dolnicar, Sara; Hurlimann, Anna; Grün, Bettina

    2014-06-15

    Branding is a key strategy widely used in commercial marketing to make products more attractive to consumers. With the exception of bottled water, branding has largely not been adopted in the water context although public acceptance is critical to the implementation of water augmentation projects. Based on responses from 6247 study participants collected between 2009 and 2012, this study shows that (1) different kinds of water - specifically recycled water, desalinated water, tap water and rainwater from personal rainwater tanks - are each perceived very differently by the public, (2) external events out of the control of water managers, such as serious droughts or floods, had a minimal effect on people's perceptions of water, (3) perceptions of water were stable over time, and (4) certain water attributes are anticipated to be more effective to use in public communication campaigns aiming at increasing public acceptance for drinking purposes. The results from this study can be used by a diverse range of water stakeholders to increase public acceptance and adoption of water from alternative sources. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  15. Managing Workplace Diversity

    Directory of Open Access Journals (Sweden)

    Harold Andrew Patrick

    2012-04-01

    Full Text Available Diversity management is a process intended to create and maintain a positive work environment where the similarities and differences of individuals are valued. The literature on diversity management has mostly emphasized on organization culture; its impact on diversity openness; human resource management practices; institutional environments and organizational contexts to diversity-related pressures, expectations, requirements, and incentives; perceived practices and organizational outcomes related to managing employee diversity; and several other issues. The current study examines the potential barriers to workplace diversity and suggests strategies to enhance workplace diversity and inclusiveness. It is based on a survey of 300 IT employees. The study concludes that successfully managing diversity can lead to more committed, better satisfied, better performing employees and potentially better financial performance for an organization.

  16. Diversity does not travel!

    DEFF Research Database (Denmark)

    Lund, Rebecca; Tienari, Janne

    2013-01-01

    In this chapter we offer insights into the social construction of diversity in Finnish organizations and society. In Finnish organizations, gender is highlighted while other markers of diversity are blotted out. 'Non-Finns' become subject to cultural assimilation. The US-based concept of Diversity...... Management becomes adopted and adapted in particular ways. Standardized concepts of diversity and its management do not travel, rather they become translated locally. In organizational practice, globalization is slow and laborious....

  17. International diversity management

    DEFF Research Database (Denmark)

    Lauring, Jakob

    2013-01-01

    While the concern with demographic diversity in organizations has increased during recent years, international diversity management still remains an understudied area. This is unfortunate since the transfer of diversity management practices within multinational corporations faces particular...... challenges in balancing between global integration and local responsiveness. The aim of this paper is to illustrate some of the central problems that multinational corporations need to deal with when transferring diversity management practices from headquarters to local subsidiaries. This is illustrated...

  18. 南水北调东线工程沿线城市尾水处理方案比选%Comparison and selection of tail water treatment programs for cities along Eastern Route of South-to-North Water Diversion Project

    Institute of Scientific and Technical Information of China (English)

    郝达平

    2013-01-01

    以洪泽县为例,综合运用水文学和生态学等理论和方法,研究南水北调东线工程沿线城市尾水处理方案的选择,最终确定蓄水塘-廊道-兼性塘-表面流湿地组合的尾水处理方案,并建议将处理工艺与景观建设相结合,建成集生态、景观、休闲、科教等功能于一体的综合性示范工程。%Hydrological and ecological integrated theories and methods were used to select tail water treatment programs for cities along the Eastern Route of the South-to-North Water Diversion Project. A case study was conducted in Hongze County. A scheme combining a storage pond, corridor, facultative pond, and surface flow wetland was determined. The treatment process and the landscape construction were combined to build a comprehensive demonstration project with integration of ecology, landscape, recreation, education, and other functions. The collection, treatment, and utilization of tail water were also conducted.

  19. Unity in Diversity.

    Science.gov (United States)

    Purves, Alan C.

    The cultural diversities of peoples and dialects in the United States have brought a richness to the English language that has made it one of the most supple of all the languages in the world. In addition to the diversity in the language are the diversities in literature, technology, nationality, politics, and styles of teaching. Teachers of…

  20. Multilevel and Diverse Classrooms

    Science.gov (United States)

    Baurain, Bradley, Ed.; Ha, Phan Le, Ed.

    2010-01-01

    The benefits and advantages of classroom practices incorporating unity-in-diversity and diversity-in-unity are what "Multilevel and Diverse Classrooms" is all about. Multilevel classrooms--also known as mixed-ability or heterogeneous classrooms--are a fact of life in ESOL programs around the world. These classrooms are often not only multilevel…

  1. Diversity cognition and climates

    NARCIS (Netherlands)

    van Knippenberg, D.; Homan, A.C.; van Ginkel, W.; Roberson, Q.M.

    2013-01-01

    Demographic diversity at work can yield performance benefits but also invite psychological disengagement and be a source of interpersonal tension. In managing this double-edged sword of demographic diversity, the role of diversity cognition (beliefs, attitudes) and climates seems particularly

  2. Diversity by design

    NARCIS (Netherlands)

    Helberger, N.

    2011-01-01

    How do you get citizens/media consumers to voluntarily choose to expose themselves to diverse content? Is there a role for government in helping people make diverse choices? Professor Helberger addresses these questions by suggesting "diversity by design" as an antidote to the ironic fact that broad

  3. Unity in Diversity.

    Science.gov (United States)

    Purves, Alan C.

    The cultural diversities of peoples and dialects in the United States have brought a richness to the English language that has made it one of the most supple of all the languages in the world. In addition to the diversity in the language are the diversities in literature, technology, nationality, politics, and styles of teaching. Teachers of…

  4. Diversity cognition and climates

    NARCIS (Netherlands)

    van Knippenberg, D.; Homan, A.C.; van Ginkel, W.; Roberson, Q.M.

    2013-01-01

    Demographic diversity at work can yield performance benefits but also invite psychological disengagement and be a source of interpersonal tension. In managing this double-edged sword of demographic diversity, the role of diversity cognition (beliefs, attitudes) and climates seems particularly promis

  5. The State of Diversity.

    Science.gov (United States)

    Josey, E. J.

    1994-01-01

    Examines what is being done to implement cultural diversity in libraries. Topics addressed include affirmative action; defining cultural diversity, including the significance of ethnicity, race, and race relations in the workplace; problems in implementing cultural diversity; and examples of successful implementation programs. (Contains three…

  6. Analysis on the Stakeholders of Water Diversion Project Cross Regions and Basins: a Case of Tao River Water Diversion Project%跨区域(流域)调水工程的利益相关者分析——以甘肃省引洮供水工程为例

    Institute of Scientific and Technical Information of China (English)

    杜立钊; 骆进仁; 钱晓东

    2011-01-01

    跨区域、流域调水是我国未来水利基础设施建设的重点之一,协调好工程建设中的利益关系是保证工程顺利实施并获取实效,以及促进相关区域可持续发展的关键.对相关利益主体进行辨析,分析他们各自福利的损益均衡条件,是建立完整的利益补偿框架的基础.从产权角度分析了洮河水资源的用水权分配问题,通过建立一个简单的基于两区域的局部均衡模型对跨区域(流域)调水工程中利益补偿问题的产生给出了福利经济学解释,最后分析引洮工程各利益主体在工程实施前后的成本收益变化,为确定补偿主客体以及进一步实施有效补偿提供依据.%Water transfer cross regions and basins will take an important part in China's water infrastructure construction in the future. In order to ensure the smooth implementation of project and obtain practical results, even to promote sustainable development of regions related, it should be attached great importance that how to coordinate the different interests associated with project construction. To identify the relevant stakeholders and analyze the equilibrium conditions of their respective benefits or loss is the foundation to establish a complete compensation framework. This paper studies the allocation of water rights of Tao River from a perspective of property economics, explains the arising of compensations in the water transfer projects cross regions and basins through the establishment of a partial equilibrium model in welfare economics, then discusses the changes of the stakeholders' costs and benefits before and after the construction of the water diverting project, which is aimed to provide the basis for the confirmation of the host-guest of compensation and the further implementation of effective compensation.

  7. Analysis on impacts of climate changes and Baojixia water diversion on Wei river runoff%气候变化及宝鸡峡引水对渭河径流量的影响分析

    Institute of Scientific and Technical Information of China (English)

    林启才; 李怀恩

    2013-01-01

    渭河宝鸡段河道年径流减少,生态基流得不到保障引起社会各界的重视.根据1954-2009年以来的降水、气温以及径流观测数据,分析降水及气温变化变化对渭河径流量的影响.采用相关系数法得到降水与径流的相关系数为0.69,正相关性好,气温与径流的相关系数为-0.73,呈明显负相关.采用降水、气温以及径流累积曲线分析得到,降水减少趋势不明显、年径流量减少趋势明显,以及气温升高趋势明显.分析认为径流减少趋势主要由降水量减少和气温升高所致.此外,1971年和2003年是两个重要突变点,主要原因是宝鸡峡渠首引水和宝鸡峡加坝加闸工程所致.%Reduction in the runoff and ecological basic flow in the Baoji reach of Wei River has attracted a great public attention over recent years.This paper analyzes the effect of changes in precipitation and air temperature on the Wei River runoff,based on the records of these two quantities and the hydrological data of the period 1954-2009.Using a correlation coefficient method,we obtained a close correlation 0.69 of runoff with precipitation,and a close but negative correlation-0.73 of runoff with air temperature.Trend analysis shows that the precipitation had decreased sligatly,while the runoff had decreased dramatically and the air temperature risen significantly.For the runoff reduction,the main reasons would be precipitation reduction and air temperature rise.The mass curve has two breaking points,one caused by the Baojixia water diversion in 1971,and the other caused by the renovation of dam and gate in this diversion project in 2003.

  8. Comprehensive Assessment of East Route Water Quality of South-to-North Water Diversion Project Based on LM-BP Neural Network%基于LM-BP网络的南水北调东线源头水质综合评价

    Institute of Scientific and Technical Information of China (English)

    夏美娟; 梁雪春

    2011-01-01

    水环境质量综合评价所涉及的评价指标众多,水环境质量等级之间也存在非线性关系.针对这种复杂情况,论文使用Matlab软件利用LM-BP神经网络算法进行水质评价,该算法具有自适应调节能力和处理复杂非线性问题的优势.将其应用于对南水北调东线源头的2个断面连续8年的水质监测数据进行综合评价.首先建立科学的网络模型结构,然后根据《地表水环境质量标准》利用Matlab的函数生成足够的训练样本和检验样本及对应的目标值训练网络,使网络具有很好的泛化能力和水质优劣分辨能力,最后利用训练好的网络对长江嘶马闸中泓断面和芒稻河二水厂断面的水质监测数据进行综合评价,结果表明,2个断面的水质属于Ⅰ类或Ⅱ类水体,其中长江嘶马闸中泓断面水质优于芒稻河二水厂断面,但2个断面都有恶化的趋势.结论对南水北调东线源头河流的污染治理有一定的参考价值.%The comprehensive evaluation of water environmental quality involves various indexes, and a non-linear relation exists among different quality levels. According to this complicated situation, the paper adopts the Matlab software and the algorithm of LM-BP neutral network to assess the water quality, the algorithm has self-adapative capacity and could deal with a variety of complex non-linear problems. The method was adopted to comprehensively evaluate the water quality at two sections of the east route of South-to-North water diversion project for eight years. Firstly, a scientific neural network model is established, secondly, according to environment quality standards for surface water, sufficient training samples and test samples and the corresponding training targets are generated by using Matlab functions. In this way, the network has very good generalization ability and performance of showing degree of water quality, finally, the trained network is used to comprehensively

  9. Intersectionality, Diversity and Gender

    DEFF Research Database (Denmark)

    Agustin, Lise Rolandsen; Siim, Birte

    2016-01-01

    In the discourses of Danish politicians on ethno-national diversity and integration, the notion of diversity is gendered, especially the articulation of the ‘working woman’ and her labor market participation. Equality, diversity and gender are, thus, intertwined in political, discursive...... constructions of national and European identities/belongings. On this basis the article claims that diversity represents a dual challenge to be conceptualized within and beyond the nation state. The article explores the formation of national and transnational identities based on analyses of political actors......’ debates about gender and diversity within the national and transnational European Polity....

  10. Work group diversity.

    Science.gov (United States)

    van Knippenberg, Daan; Schippers, Michaéla C

    2007-01-01

    Work group diversity, the degree to which there are differences between group members, may affect group process and performance positively as well as negatively. Much is still unclear about the effects of diversity, however. We review the 1997-2005 literature on work group diversity to assess the state of the art and to identify key issues for future research. This review points to the need for more complex conceptualizations of diversity, as well as to the need for more empirical attention to the processes that are assumed to underlie the effects of diversity on group process and performance and to the contingency factors of these processes.

  11. Diversity Management: Seeking Validation

    Directory of Open Access Journals (Sweden)

    M. Tony Bledsoe

    2011-01-01

    Full Text Available Diversity management is widely valued in higher education today, but closer examination often reveals a lack of action to support the level of diversity that institutions claim to embrace in many of their strategic documents. This paper includes an assessment of diversity management within South Carolina’s technical colleges and an examination of survey results.  It is a companion study to a prior study of diversity in North Carolina Independent Colleges and Universities (NCICU.  The purpose of that research was to review campus-wide documents and structure of schools in the NCICU to determine diversity transparency (Bledsoe/Oatsvall.

  12. Linking Diversity and Differentiation

    Directory of Open Access Journals (Sweden)

    Hans-Rolf Gregorius

    2010-03-01

    Full Text Available Generally speaking, the term differentiation refers to differences between collections for the distribution of specified traits of their members, while diversity deals with (effective numbers of trait states (types. Counting numbers of types implies discrete traits such as alleles and genotypes in population genetics or species and taxa in ecology. Comparisons between the concepts of differentiation and diversity therefore primarily refer to discrete traits. Diversity is related to differentiation through the idea that the total diversity of a subdivided collection should be composed of the diversity within the subcollections and a complement called “diversity between subcollections”. The idea goes back to the perception that the mixing of differentiated collections increases diversity. Several existing concepts of “diversity between subcollections” are based on this idea. Among them, β-diversity and fixation (inadvertently called differentiation are the most prominent in ecology and in population genetics, respectively. The pertaining measures are shown to quantify the effect of differentiation in terms of diversity components, though from a dual perspective: the classical perspective of differentiation between collections for their type compositions, and the reverse perspective of differentiation between types for their collection affiliations. A series of measures of diversity-oriented differentiation is presented that consider this dual perspective at two levels of diversity partitioning: the overall type or subcollection diversity and the joint type-subcollection diversity. It turns out that, in contrast with common notions, the measures of fixation (such as FST or GST refer to the perspective of type rather than subcollection differentiation. This unexpected observation strongly suggests that the popular interpretations of fixation measures must be reconsidered.

  13. Surveillance of schistosomiasis in Jinbao Channel areas in east route of Southto-North Water Diversion Project%南水北调东线工程金宝航道区域血吸虫病疫情监测

    Institute of Scientific and Technical Information of China (English)

    孙道宽; 李倩; 王启龙

    2011-01-01

    Objective To understand the dynamic of the endemic situation of schistosomiasis in Jinbao Channel areas, so as to provide the evidence for surveillance and early-warning of schistosomiasis in the east route of the South-to-North Water Diversion Project. Methods The conventional methods were used for the surveillance of Oncomelarda hupensis snails in the first grade tributary and the flood land of Jinbao Channel. The methods of net salvage and attracting snails with rice straw curtains were used for snail surveys underwater in the surveillance sites. The residents, fishermen and crew were surveyed for schistosomiasis in the regions along the Jinbao Channel. The situation of the fishing boats carrying snails were surveyed, too. Results The accumulated areas where snails checked were 364.20 hm2. A total of 2 785 kg floats were collected and 400 pieces of rice straw curtains were placed in the surveillance sites, but no snails were found from 2006 to 2010. A total of 7 951 persons were surveyed for schistosomiasis by the serological test, and the total positive rate was 0.92%. The positive rates in the residents and fishermen were 0.79% and 1.55%, respectively. The fishmen's seropositive rate was higher than the residents' (χ2=7.11, P< 0.01). A total of 65 people received fecal examinations and there was one infected case. A total of 54 fish boats and 93 fishing gears were detected and no snails were found. Conclusions There are no snails and schistosomiasis transmission, but there are the risks of imported schistosomiasis infectious source in the regions along the Jinbao Channel in the east route of the South-to-North Water Diversion Project, therefore, the long-term surveillance is necessary.%目的 了解南水北调东线工程金宝航道血吸虫病疫情动态,为东线工程血吸虫病监测预警提供科学依据.方法 每年对金宝航道及其一级支流、周边滩地进行钉螺调查,选择金宝航道退水闸段为监测点,采用网捞法和稻

  14. 鄱阳湖7个河口水体中细菌多样性和组成特征%Bacterial diversities and compositions in seven different estuarine water columns of Poyang Lake

    Institute of Scientific and Technical Information of China (English)

    圣平; 于一尊; 田晓娟; 黄江丽; 张志红; 丁建南

    2016-01-01

    本文对鄱阳湖7个河口(赣江、抚河、信江、乐安河、昌江、饶河和修河)水体的理化特性进行了分析,并采用细菌16S rRNA基因MiSeq测序的方法对其多样性和组成进行了研究。结果表明,乐安河水体总氮含量最高,信江水体总磷含量最高。乐安河、修河和饶河水体细菌丰度高于其它河口,而修河、昌江和饶河水体细菌多样性则相对较高。水体细菌群落组成分析结果表明,在7个河口水体中变形菌门细菌均占优势,其次为放线菌门和拟杆菌门细菌。而在纲水平,在7个河口水体中β-变形菌纲细菌占优势,其次为α-变形菌纲细菌和放线菌纲细菌。相关性分析结果表明,水体pH和细菌群落多样性呈显著负相关关系,而总氮和氨态氮含量和细菌群落多样性呈显著正相关性。%In this study, we analyzed environmental factors of seven different estuarine water columns of Poyang Lake (Gan, Fu, Xin, Le’an, Chang, Rao, and Xiu River), and the bacterial community compositions in these different estuarine sediments were analyzed using the 16S rRNA gene targeted metagenomic approach. Our results showed that Le’an River had the highest total nitrogen content, and Xin River had the highest total phosphorus content. For the bacterial richness and diversity in these seven different estuaries, we found that Le’an, Xiu and Rao rivers showed the higher bacterial richness than other estuarines. Xiu, Chang and Rao rivers showed higher bacterial diversities than others. Bacterial composition analysis indicated that Proteobacteria phylum was dominant in all water samples, followed by Actinobacteria and Bacteroidetes. At the class level, all samples were numerically dominated by members of the Betaproteobacteria, Alphaproteobacteria and Actinobacteria. Furthermore, according to the Spearman’s correlation analysis, we found that there were signiifcant negative relationships between the

  15. Study on economic compensation of water source area with Taohe River Water Diversion Project based on opportunity cost method%基于机会成本法的引洮工程水源区经济补偿研究

    Institute of Scientific and Technical Information of China (English)

    袁泉; 骆进仁

    2016-01-01

    In order to ensure that the water source area is rich in rainfall resources, we summarized related research results in regard to water source area compensation, and defined the scope of the water source area for the Taohe River Diversion Project and possible compensation forms. Based on the correlated objective relationship between GDP and COD, we established the regression equation and calculated the opportunity costs of the limitations for the water source area. The amount of compensation was calculated to be 1018. 9725 million yuan per year, of which the wages and benefits, taxes, and business profit were 611. 3835 million yuan, 203. 7945 million yuan, and 203. 7945 million yuan, respectively. We also put forward recommendations for the compensation system, compensation bodies, and compensation forms.%为确保水源区雨水富集功能,梳理了水源区补偿的相关研究成果,界定了引洮工程水源区范围及其可能的补偿形式,利用GDP与COD之间存在的相关客观关系,建立回归方程,求得水源区受限的机会成本。测算出每年应该补偿的金额为101897.25万元,其中工资福利费、税收和企业利润分别为61138.35、20379.45和20379.45万元。提出建立补偿制度、确定补偿主体和确立补偿的方式等政策建议。

  16. Quasi-market Model of Water Price in South-to-North Water Diversion Project Based on Decision-making Environment Theory%基于决策环境理论的南水北调水价准市场定价模式研究

    Institute of Scientific and Technical Information of China (English)

    曾雪婷; 李永平

    2013-01-01

    南水北调工程是极具社会公益性,又具经济效益的基础建设工程,其工程特点决定了其主要由国家投入、运营和管理,但由此带来的水价过低、水资源利用效率低下等问题,影响了整个工程水资源的可持续利用。因此,在南水北调水价管理体系中引入水市场理念,运用决策环境分析理论明确市场决策及政府决策在水价定形成中的作用;在结合工程实际的基础上,按照完全成本核算的方法,合理计入资源与环境水价,并在两部制水价的基础上进行水价调整。以“准市场”化模式来完善工程水价的形成机制和管理模式,从而实现南水北调水价机制的可持续发展及水资源的高效配置。%The Sout h-to-Nort h Water Diversion Project is an infrastructure engineering project w it h social public w elfare and eco-nomic benefit, and its engineering characteristics determine the national investment , operat ion, and management, w hich might re-sult in the low w ater price and low w ater resources utilization efficiency, and t herefore affect the sust ainable utilization of w ater resources. Therefore, the w ater market concept is introduced into the management system of the South-to-North Water Diver-sion Project, and the decision-making environment theory is applied to determine t he roles of market and government decision-makings in t he water price management. According to actual situations of project, w ater price is formulated based on t he method of ful cost accounting and the consideration of environment price and resources price. The“ quasi-maket” model is used to im-prove the formulation and management mechanism of engineering w at er price, which is beneficial for the sustainable develop-ment of w ater price mechanism in the South-to-North Water Diversion Project and effective allocat ion of w ater resources.

  17. Gender diversity in STEM

    Science.gov (United States)

    Beijerinck, Herman C. W.

    2017-03-01

    There is a strong business case for the value of diversity. Research by the World Economic Forum shows a 36% higher return on equity (ROE) for companies having a workforce with strong gender diversity1. Also growth is influenced in a positive way: in 2009 - 2012 companies with a strong female leadership have increased their ROE by 10.1% as compared to an average of 7.4% for the rest. Diversity is not a problem but a solution!2

  18. Genetic diversity assessed using microsatellite DNA of spiny head croaker ( Collichthys lucidus) from the Zhoushan offshore waters%舟山近海棘头梅童鱼群体遗传多样性微卫星DNA分析

    Institute of Scientific and Technical Information of China (English)

    林能锋; 苏永全; 丁少雄; 王军

    2011-01-01

    应用6对可在棘头梅童鱼(Collichthy lucidels)中扩增的大黄鱼(Rseudosciaena Crocea)微卫星引物对浙江舟山近海的棘头梅童鱼群体进行PCR扩增,变性聚丙烯酰胺凝胶电泳分析扩增产物.6对引物在群体中共扩增出46个等位基因,平均每个位点得到5.308 0个有效等位基因.各位点的PIC值为0.4126~0.893 5(平均值0.670 8),PCIC4和PC8F5为中度多态性位点,PC4H12、PC5E11、PCIOF10及PC10G6为高度多态性位点,这些位点可以做为棘头梅童鱼群体遗传学研究的有效的分子遗传标记.6个位点的连锁分析显示,各位点间不存在明显的连锁关系.各位点在群体中的观测杂合度(Ho)为0.4545~0.9167(平均值0.6591),期望杂合度(He)为0.4680~0.9019(平均值0.6997),与其他海水鱼类比较,浙江近海的棘头梅童鱼群体遗传多样性偏低.对各位点进行Hardy-Weinberg平衡检测表明,PC4H12、PC10F10及PC10G6位点的等位基因频率偏离了平衡,综合现有的资源调查资料,遗传多样性的降低与近年来棘头梅童鱼资源的下降有关.%Spiny head croaker ( Collichthy lucidus) is a demersal and diminutive fish species, and was an abundant resource in the East China Sea until about 20 years ago. With the development of marine fisheries, much of the breeding stock of spiny head croaker and juvenile populations were overfished employing the traditional two-stick stow net method. To propose reasonable protection of the C. lucidus resource, it is important to understand the background of its population genetics. In this study, samples of spiny head croaker from Zhoushan offshore waters in Zhejiang province were collected and the genetic diversity analyzed. Six microsatellite loci developed from P.crocea were employed to assess the levels of allelic diversity and heterozygosity of the C. lucidus population. A total of 46 alleles were obtained from 24 individuals at six loci. The number of alleles per locus ranged from 4 to 13

  19. The dynamical landscape of marine phytoplankton diversity.

    Science.gov (United States)

    Lévy, Marina; Jahn, Oliver; Dutkiewicz, Stephanie; Follows, Michael J; d'Ovidio, Francesco

    2015-10-01

    Observations suggest that the landscape of marine phytoplankton assemblage might be strongly heterogeneous at the dynamical mesoscale and submesoscale (10-100 km, days to months), with potential consequences in terms of global diversity and carbon export. But these variations are not well documented as synoptic taxonomic data are difficult to acquire. Here, we examine how phytoplankton assemblage and diversity vary between mesoscale eddies and submesoscale fronts. We use a multi-phytoplankton numerical model embedded in a mesoscale flow representative of the North Atlantic. Our model results suggest that the mesoscale flow dynamically distorts the niches predefined by environmental contrasts at the basin scale and that the phytoplankton diversity landscape varies over temporal and spatial scales that are one order of magnitude smaller than those of the basin-scale environmental conditions. We find that any assemblage and any level of diversity can occur in eddies and fronts. However, on a statistical level, the results suggest a tendency for larger diversity and more fast-growing types at fronts, where nutrient supplies are larger and where populations of adjacent water masses are constantly brought into contact; and lower diversity in the core of eddies, where water masses are kept isolated long enough to enable competitive exclusion.

  20. Large infrequently operated river diversions for Mississippi delta restoration

    Science.gov (United States)

    Day, John W.; Lane, Robert R.; D'Elia, Christopher F.; Wiegman, Adrian R. H.; Rutherford, Jeffrey S.; Shaffer, Gary P.; Brantley, Christopher G.; Kemp, G. Paul

    2016-12-01

    Currently the Mississippi delta stands as a highly degraded and threatened coastal ecosystem having lost about 25% of coastal wetlands during the 20th century. To address this problem, a 50 billion, 50-year restoration program is underway. A central component of this program is reintroduction of river water back into the deltaic plain to mimic natural functioning of the delta. However, opposition to diversions has developed based on a number of perceived threats. These include over-freshening of coastal estuaries, displacement of fisheries, perceived water quality problems, and assertions that nutrients in river water leads to wetland deterioration. In addition, growing climate impacts and increasing scarcity and cost of energy will make coastal restoration more challenging and limit restoration options. We address these issues in the context of an analysis of natural and artificial diversions, crevasse splays, and small sub-delta lobes. We suggest that episodic large diversions and crevasses (>5000 m3 s-1) can build land quickly while having transient impacts on the estuarine system. Small diversions (water level stress. We use land building rates for different sized diversions and impacts of large periodic inputs of river water to coastal systems in the Mississippi delta to conclude that high discharge diversions operated episodically will lead to rapid coastal restoration and alleviate concerns about diversions. Single diversion events have deposited sediments up to 40 cm in depth over areas up to 130-180 km2. This approach should have broad applicability to deltas globally.

  1. Putting Diversity to Work

    DEFF Research Database (Denmark)

    Holck, Lotte

    2016-01-01

    Purpose: The purpose of this article is to critically explore why a diversity agenda in favor of equal opportunities failed despite apparent organizational support and commitment to diversity. Design/methodology/approach: Drawing on data from a municipal center, this study inquires into how organ...

  2. Advancing Diversity in STEM

    Science.gov (United States)

    Hill, Paul L.; Shaw, Rose A.; Taylor, Jan R.; Hallar, Brittan L.

    2011-01-01

    Although progress has been made, greater efforts are needed to promote faculty diversity at the college and university levels, especially in STEM fields. Thus, it is important to elucidate best practices both for increasing awareness of diversity issues pertaining to higher education and for implementing change. This article focuses on the…

  3. Diversity and Social Cohesion

    Science.gov (United States)

    Pagani, Camilla

    2014-01-01

    The issue of diversity, in its broadest sense, is discussed here in its relation to social cohesion, cross-cultural relations, ingroup-outgroup relations and educational interventions. The main thesis of the paper is that real social cohesion in an ingroup rests on the acknowledgment of and the dialog with the diversities of the members of the…

  4. The Diversity Machine.

    Science.gov (United States)

    Lynch, Frederick R.

    1997-01-01

    Discusses social policy influences on the workplace and how the linkage of demographic change with multiculturalism has led to changes in organizational policies. It examines the emergence of diversity management practice, the influence of globalizing markets in driving corporate diversity policies, and the roles of corporate and government…

  5. Evolution & Diversity in Plants.

    Science.gov (United States)

    Pearson, Lorentz C.

    1988-01-01

    Summarizes recent findings that help in understanding how evolution has brought about the diversity of plant life that presently exists. Discusses basic concepts of evolution, diversity and classification, the three-line hypothesis of plant evolution, the origin of fungi, and the geologic time table. Included are 31 references. (CW)

  6. 南水北调中线工程改性土余料再利用研究%Research on re-utilization of surplus modified soil in Middle Route Project of South to North Water Diversion

    Institute of Scientific and Technical Information of China (English)

    张胜明; 王德云; 刘勇

    2014-01-01

    The useable soil sources for the most bidding sections of Middle Route Project of South to North Water Diversion are insufficient and using cement-mixed modified soil to replace the canal soil is a main measure for guaranteeing the canal slope stability. In the backfilling construction, large amount of surplus modified soil was produced after slope cutting and the indoor and field tests discovered that the surplus modified soil could be used as backfilling soil. In the test, the selection method of the maxi-mum dry density, construction technology and application scope of the modified soil were determined. The soil re-utilization has increased backfilling soil sources in weak expansive soil area, which could save farmland, resources and protect environment.%南水北调中线工程大部分标段可用土料源不足,采用弱膨胀土掺入水泥(简称水泥改性土,下同)后对膨胀土渠段进行换填施工,是确保膨胀土渠段边坡稳定的主要措施之一。在填筑施工中,按设计坡比削坡后产生大量的改性土削坡余料,通过室内试验及现场试验验证了改性土余料亦可用于工程回填。为此,确定了改性土余料最大干密度的选择方法、改性土余料的施工工艺及使用部位。对余料土的再利用,保证了弱膨胀土地区土方施工的回填料源,避免或减少了农田占压面积,取得了节约资源与保护环境的双重效果。

  7. Managing Protean Diversity

    DEFF Research Database (Denmark)

    Marfelt, Mikkel Mouritz; Muhr, Sara Louise

    2016-01-01

    . In this article, we follow the call for critically investigating the contexts influencing diversity management by analyzing the development of a global human resource management project initiated to promote a culturally diverse workforce. We find that despite good intentions, as well as support from the top......Recently, global workforce diversity and its management have received criticism for not paying attention to the contextual influence stemming from socially constructed dialectics of power and politics. These contextual dynamics, however, tend to be viewed as external to the organization...... management, the project dissolves through micropolitics and power dynamics. We contribute to the critical literature on workforce diversity by identifying how organizational contextual dynamics influence the way the concept of workforce diversity is constructed and understood at work. Based on these findings...

  8. The marine diversity spectrum

    DEFF Research Database (Denmark)

    Reuman, Daniel C.; Gislason, Henrik; Barnes, Carolyn

    2014-01-01

    of taxonomy (all the species in a region regardless of clade) are much less studied but are equally important and will illuminate a different set of ecological and evolutionary processes. We develop and test a mechanistic model of how diversity varies with body mass in marine ecosystems. The model predicts...... the form of the diversity spectrum', which quantifies the distribution of species' asymptotic body masses, is a species analogue of the classic size spectrum of individuals, and which we have found to be a new and widely applicable description of diversity patterns. The marine diversity spectrum...... is predicted to be approximately linear across an asymptotic mass range spanning seven orders of magnitude. Slope -0 center dot 5 is predicted for the global marine diversity spectrum for all combined pelagic zones of continental shelf seas, and slopes for large regions are predicted to lie between -0 center...

  9. On Ecological and Environmental Protection of Water Source Area in South-to-North Middle Line Water Diversion Project under Eco-Tourism%生态旅游背景下的南水北调中线水源区生态环境保护研究

    Institute of Scientific and Technical Information of China (English)

    付景保; 高军波

    2013-01-01

    Ecological and environmental problems of water source area in South-to-North middle line water diversion project have become the focus of attention widely. To study the ecological and environmental protection of the water source area has important practical significance from the perspective of the eco-tourism. By using field investigation and document analysis method, on the basis of studying ecological environment overview and eco-tourism development in water source area, the articles summed up the eco-tourism is a strategic choice industry to promote the protection of the ecological environment in the water source area, and proposed some development countermeasures like we should strengthen the government's macroeconomic and scientific management about protection work of the ecological environment of the water area; and should adjust the industrial structure, and actively develop eco-tourism; to carry out soil and water conservation, Green Jiangshan construction, to create a good environment for eco-tourism; and strengthen civic education on environmental protection, improve environmental protection awareness; re-layout the new residents area conducive to environmental protection with the new rural transformation; to establish well-detection environment system and compensation mechanism of ecology and water resource.%南水北调中线工程水源区生态环境问题已成为目前广为关注的热点.从生态旅游的视角研究水源区生态环境保护具有重要的现实意义.文章通过实地调查与文献分析方法,在研究水源区生态环境概况及生态旅游发展的基础上,总结了生态旅游是促进水源区生态环境保护的战略性选择产业,并提出了水源区生态环境保护工作要加强政府宏观管理,进行依法管理、科学管理;要大力调整产业结构,积极发展生态旅游业;要开展水土保持、绿化江山建设,营造良好的生态旅游环境;要加强公民环保教育,提高环保

  10. Trainee Readiness For Diversity Training

    Directory of Open Access Journals (Sweden)

    Yunhyung Chung

    2013-11-01

    Full Text Available Although trainee readiness is critical for diversity training effectiveness, extant research has not paid attention to the relationship between trainee readiness for diversity training and diversity training outcomes. This study identifies motivational, behavioral, and cognitive trainee readiness for diversity training and proposes a theoretical framework of how individual characteristics (perceived discrimination, demographic attributes, and previous diversity-related experience and organizational characteristics (diversity climate and demographic dissimilarity influence motivational, behavioral, and cognitive trainee readiness for diversity training.

  11. Chamaedorea: diverse species in diverse habitats

    Directory of Open Access Journals (Sweden)

    1992-01-01

    Full Text Available DIVERSES ESPÈCES DANS DIVERS HABITATS. Des espèces extraordinairement diverses se trouvant dans des habitats également divers caractérisent Chamaedorea, un genre qui compte environ 90 espèces dioïques limitées aux sous-bois des forêts néo-tropicales constamment dans la pluie et les nuages du Mexique à la Bolivie et à l’Équateur. Une vaste gamme de formes biologiques, de tiges, de feuilles, d’inflorescences, de fleurs, et de fruits reflète la diversité des espèces. Bien que le genre soit plus riche en espèces dans les forêts denses et humides situées entre 800-1,500 mètres d’altitude, quelques espèces exceptionnelles se trouvent dans des forêts moins denses et/ou occasionnellement sèches, sur des substances dures ou dans d’autres habitats inhabituels. DIVERSAS ESPECIES EN DIVERSOS HÁBITATS. Especies notablemente diversas presentes en habitats igualmente diversos caracterizan a Chamaedorea, un genero de aproximadamente 90 especies dioicas limitadas al sotobosque de los bosques lluviosos y nubosos neotropicales desde Mexico hasta Bolivia y Ecuador. Una amplia gama de formas biológicas, tallos, hojas, inflorescencias, flores, y frutos refleja la diversidad de las especies. Aunque el género es más rico en especies en los bosques densos y húmedos de 800-1,500 metros de altura, unas pocas especies excepcionales ocurren en bosques abiertos o ocasionalmente secos, en substrato severo o en otros habitats extraordinarios. Remarkably diverse species occurring in equally diverse habitats characterize Chamaedorea, a genus of about 90, dioecious species restricted to the understory of neotropical rain and cloud forests from Mexico to Bolivia and Ecuador. A vast array of habits, stems, leaves, inflorescences, flowers, and fruits reflect the diversity of species. Although the genus is most species-rich in dense, moist or wet, diverse forests from 800-1,500 meters elevation, a few exceptional species occur in open and/or seasonally

  12. Effects of clipping, fertilizing and watering on the relationship between species diversity,functional diversity and primary productivity in alpine meadow of China%刈割、施肥和浇水对高寒草甸物种多样性、功能多样性与初级生产力关系的影响

    Institute of Scientific and Technical Information of China (English)

    李晓刚; 朱志红; 周晓松; 袁芙蓉; 樊瑞俭; 许曼丽

    2011-01-01

    通过在高寒矮嵩草(Kobresia humilis)草甸为期4年的刈割(留茬1 cm、3 cm及不刈割)、施肥(尿素7.5 g·m-2a-1+磷酸二铵1.8 g.m-2·a-1、不施肥)和浇水(20.1 kg·m-2·a-1、不浇水)控制实验,对该生态系统中功能多样性与物种多样性的变化及其与初级生产力关系进行了研究.结果表明:刈割和施肥显著影响植物性状和生产力,而浇水作用微弱.刈割对物种多样性无影响,但对不同功能多样性指数的影响不同:施肥降低了物种多样性和以所有性状(除植株高度外)量化的功能多样性;浇水仅对物种丰富度有微弱影响.各功能多样性的平均值能更好地反映群落物种间的功能差异.功能多样性和物种多样性呈正相关或不相关,且二者与初级生产力的关系可表现为正相关、负相关和不相关,说明三者间的关系是性状依赖的,并受生境资源状况和刈割扰动的影响.植物功能性状对群落初级生产力有更加直接的影响.在考虑生物多样性对生态系统功能的影响时,应更加注重对植物功能属性变化的研究.%Aims Although much attention has been paid for the relationship between the biodiversity and ecosystem functioning, little is known about the ecosystem consequences of changes. In addition, the question whether species diversity (SD) can co-vary with functional diversity (FD) is unanswered. We used the Rao index to quantify FD in order to explore this question through comparison of different components of biodiversity and their effects on primary productivity (PP).Methods A field manipulation experiment was conducted in alpine meadow at the Haibei Research Station of the Chinese Academy of Sciences from 2007 to 2010. The experiment used a split-plot design with clipping treatment in the whole plot using three clipping levels (stubbled 1 cm, 3 cm and undipped). Subplots were treated with fertilizer (urea 7.5 gm- 2a-1 + ammonium phosphate 1.8 gm-2a-1 and

  13. Historical legacies in world amphibian diversity revealed by the turnover and nestedness components of Beta diversity.

    Directory of Open Access Journals (Sweden)

    Andrés Baselga

    Full Text Available Historic processes are expected to influence present diversity patterns in combination with contemporary environmental factors. We hypothesise that the joint use of beta diversity partitioning methods and a threshold-based approach may help reveal the effect of large-scale historic processes on present biodiversity. We partitioned intra-regional beta diversity into its turnover (differences in composition caused by species replacements and nestedness-resultant (differences in species composition caused by species losses components. We used piecewise regressions to show that, for amphibian beta diversity, two different world regions can be distinguished. Below parallel 37, beta diversity is dominated by turnover, while above parallel 37, beta diversity is dominated by nestedness. Notably, these regions are revealed when the piecewise regression method is applied to the relationship between latitude and the difference between the Last Glacial Maximum (LGM and the present temperature but not when present energy-water factors are analysed. When this threshold effect of historic climatic change is partialled out, current energy-water variables become more relevant to the nestedness-resultant dissimilarity patterns, while mountainous areas are associated with higher spatial turnover. This result suggests that nested patterns are caused by species losses that are determined by physiological constraints, whereas turnover is associated with speciation and/or Pleistocene refugia. Thus, the new threshold-based view may help reveal the role of historic factors in shaping present amphibian beta diversity patterns.

  14. Historical legacies in world amphibian diversity revealed by the turnover and nestedness components of Beta diversity.

    Science.gov (United States)

    Baselga, Andrés; Gómez-Rodríguez, Carola; Lobo, Jorge M

    2012-01-01

    Historic processes are expected to influence present diversity patterns in combination with contemporary environmental factors. We hypothesise that the joint use of beta diversity partitioning methods and a threshold-based approach may help reveal the effect of large-scale historic processes on present biodiversity. We partitioned intra-regional beta diversity into its turnover (differences in composition caused by species replacements) and nestedness-resultant (differences in species composition caused by species losses) components. We used piecewise regressions to show that, for amphibian beta diversity, two different world regions can be distinguished. Below parallel 37, beta diversity is dominated by turnover, while above parallel 37, beta diversity is dominated by nestedness. Notably, these regions are revealed when the piecewise regression method is applied to the relationship between latitude and the difference between the Last Glacial Maximum (LGM) and the present temperature but not when present energy-water factors are analysed. When this threshold effect of historic climatic change is partialled out, current energy-water variables become more relevant to the nestedness-resultant dissimilarity patterns, while mountainous areas are associated with higher spatial turnover. This result suggests that nested patterns are caused by species losses that are determined by physiological constraints, whereas turnover is associated with speciation and/or Pleistocene refugia. Thus, the new threshold-based view may help reveal the role of historic factors in shaping present amphibian beta diversity patterns.

  15. Studies on the Eco-compensation and Mechanism Construction for Water Source Area of South-to-north Water Diversion Project in Henan Province%南水北调中线河南水源地生态补偿机制构建研究

    Institute of Scientific and Technical Information of China (English)

    樊万选; 夏丹; 朱桂香

    2012-01-01

    南水北调是国家进行跨流域水资源优化配置的一项重大战略决策,而中线工程的开工建设涉及到受水区、水源区的各方利益主体。以淅川县等6县(市)为研究对象,通过了解水源区的基本情况,结合国内外的生态补偿理论,分析了水源区建立生态补偿机制的必要性,使用机会成本法对水源区的生态补偿标准进行了核算,并且对水源区生态补偿机制的构建提出了一定的政策建议,认为国家在加大对水源区财政补贴的同时,应积极鼓励水源区推行自发交易式的市场补偿模式和以生态产业为主的自我补偿模式。%South-to-North water diversion project is a significant strategic decision that the country carries on the cross basin water resources optimization disposition.The construction of Middle Route Project involves different interest subject in water-receiving area and Water Source Area.On the basis of researching nature and social conditions of headwaters area including six countries and ecological compensation theories of domestic and international,it is necessary to establish ecological compensation mechanism of headwaters area.By the ways of opportunity cost calculation,this paper accounts the ecological compensation funds.Proposals are also made for the ecological compensation mechanism,and the point is that there should be much more financial subsidies for the headwaters area,and the implementation of market compensation moods and self-compensations moods shall be encouraged.

  16. CERN Diversity Newsletter - July 2015

    CERN Document Server

    Kaltenhauser, Kristin; CERN. Geneva. HR Department

    2015-01-01

    The first official edition of the CERN Diversity Newsletter, informing on recent and ongoing diversity activities, and interesting reads, videos and other links related to diversity. Subscribe here: https://diversity.web.cern.ch/2015/07/subscribe-diversity-newsletter

  17. Urban thermal diversity

    Institute of Scientific and Technical Information of China (English)

    KoenSTEEMERS; MarylisRAMOS; MariaSINOU

    2003-01-01

    This paper introduces the interrelationships between urban form, microclimate and thermal comfort. It draws on recent research of monitoring, surveying and modelling urban thermal characteristics and proposes a method of mapping urban diversity. Because the urban context provides a rich and varied environment that influences the way we use urban spaces (movement, sequence, activity) and how we feel in them (stimulation, thermal comfort), the aim here is to highlight the notion of diversity. Thus thermal diversity is used as a measure of the urban environment, rather than more conventional spatially or temporally fixed average values.