WorldWideScience

Sample records for thermal microbial habitat

  1. Using Crustal Fluids to Peer Into the Subseafloor Microbial Habitat

    Science.gov (United States)

    Huber, J. A.

    2008-12-01

    In hard rock seafloor environments, fluids emanating from the basement are one of the best windows into the subseafloor and its resident microbial community. These low-temperature crustal fluids are ubiquitous at both active hydrothermal systems and ridge flank environments. Over the last 15 years, studies of the microbial communities in crustal fluids from eruptive events, drill holes, ridge flanks, and hydrothermal seamounts have revealed a phylogenetically and physiologically diverse microbial community, representing a wide spectrum of thermal tolerances and metabolic strategies from both the subseafloor and the deep sea. In addition, emerging technologies in seafloor sampling capacity and microbial ecology are rapidly increasing our ability to study this difficult habitat. This presentation will provide an overview of what we have learned about the population structure, genomic repertoire, and physiological function of microbes in crustal fluids and what the future holds for subseafloor biosphere research. Data will be integrated with geochemical measurements in crustal environments to better define the subseafloor habitat and its resident microbial community.

  2. Threatened corals provide underexplored microbial habitats.

    Directory of Open Access Journals (Sweden)

    Shinichi Sunagawa

    Full Text Available Contemporary in-depth sequencing of environmental samples has provided novel insights into microbial community structures, revealing that their diversity had been previously underestimated. Communities in marine environments are commonly composed of a few dominant taxa and a high number of taxonomically diverse, low-abundance organisms. However, studying the roles and genomic information of these "rare" organisms remains challenging, because little is known about their ecological niches and the environmental conditions to which they respond. Given the current threat to coral reef ecosystems, we investigated the potential of corals to provide highly specialized habitats for bacterial taxa including those that are rarely detected or absent in surrounding reef waters. The analysis of more than 350,000 small subunit ribosomal RNA (16S rRNA sequence tags and almost 2,000 nearly full-length 16S rRNA gene sequences revealed that rare seawater biosphere members are highly abundant or even dominant in diverse Caribbean corals. Closely related corals (in the same genus/family harbored similar bacterial communities. At higher taxonomic levels, however, the similarities of these communities did not correlate with the phylogenetic relationships among corals, opening novel questions about the evolutionary stability of coral-microbial associations. Large proportions of OTUs (28.7-49.1% were unique to the coral species of origin. Analysis of the most dominant ribotypes suggests that many uncovered bacterial taxa exist in coral habitats and await future exploration. Our results indicate that coral species, and by extension other animal hosts, act as specialized habitats of otherwise rare microbes in marine ecosystems. Here, deep sequencing provided insights into coral microbiota at an unparalleled resolution and revealed that corals harbor many bacterial taxa previously not known. Given that two of the coral species investigated are listed as threatened under

  3. Effect of pesticides on microbial communities in container aquatic habitats

    Science.gov (United States)

    Mosquitoes develop in a variety of aquatic habitats and feed on microbial communities associated with decaying organic matter. These aquatic habitats are often embedded within and around agricultural lands and are frequently exposed to agricultural chemicals. We used a microcosm approach to examine ...

  4. Distinguishing between Microbial Habitats Unravels Ecological Complexity in Coral Microbiomes.

    Science.gov (United States)

    Apprill, Amy; Weber, Laura G; Santoro, Alyson E

    2016-01-01

    The diverse prokaryotic communities associated with reef-building corals may provide important ecological advantages to their threatened hosts. The consistency of relationships between corals and specific prokaryotes, however, is debated, and the locations where microbially mediated processes occur in the host are not resolved. Here, we examined how the prokaryotic associates of five common Caribbean corals with different evolutionary and ecological traits differ across mucus and tissue habitats. We used physical and chemical separation of coral mucus and tissue and sequencing of partial small-subunit rRNA genes of bacteria and archaea from these samples to demonstrate that coral tissue and mucus harbor unique reservoirs of prokaryotes, with 23 to 49% and 31 to 56% of sequences exclusive to the tissue and mucus habitats, respectively. Across all coral species, we found that 46 tissue- and 22 mucus-specific microbial members consistently associated with the different habitats. Sequences classifying as "Candidatus Amoebophilus," Bacteroidetes-affiliated intracellular symbionts of amoebae, emerged as previously unrecognized tissue associates of three coral species. This study demonstrates how coral habitat differentiation enables highly resolved examination of ecological interactions between corals and their associated microorganisms and identifies previously unrecognized tissue and mucus associates of Caribbean corals for future targeted study. IMPORTANCE This study demonstrates that coral tissue or mucus habitats structure the microbiome of corals and that separation of these habitats facilitates identification of consistent microbial associates. Using this approach, we demonstrated that sequences related to "Candidatus Amoebophilus," recognized intracellular symbionts of amoebae, were highly associated with the tissues of Caribbean corals and possibly endosymbionts of a protistan host within corals, adding a further degree of intricacy to coral holobiont symbioses

  5. Microbial diversity of extreme habitats in human homes

    Directory of Open Access Journals (Sweden)

    Amy M. Savage

    2016-09-01

    Full Text Available High-throughput sequencing techniques have opened up the world of microbial diversity to scientists, and a flurry of studies in the most remote and extreme habitats on earth have begun to elucidate the key roles of microbes in ecosystems with extreme conditions. These same environmental extremes can also be found closer to humans, even in our homes. Here, we used high-throughput sequencing techniques to assess bacterial and archaeal diversity in the extreme environments inside human homes (e.g., dishwashers, hot water heaters, washing machine bleach reservoirs, etc.. We focused on habitats in the home with extreme temperature, pH, and chemical environmental conditions. We found a lower diversity of microbes in these extreme home environments compared to less extreme habitats in the home. However, we were nonetheless able to detect sequences from a relatively diverse array of bacteria and archaea. Habitats with extreme temperatures alone appeared to be able to support a greater diversity of microbes than habitats with extreme pH or extreme chemical environments alone. Microbial diversity was lowest when habitats had both extreme temperature and one of these other extremes. In habitats with both extreme temperatures and extreme pH, taxa with known associations with extreme conditions dominated. Our findings highlight the importance of examining interactive effects of multiple environmental extremes on microbial communities. Inasmuch as taxa from extreme environments can be both beneficial and harmful to humans, our findings also suggest future work to understand both the threats and opportunities posed by the life in these habitats.

  6. Destiny of microbial aerosol in confined habitat

    Science.gov (United States)

    Viacheslav, Ilyin; Tikhomirov, Alexander A.; Novikova, Nataliya; Nickolay Manukovsky, D..; Kharin, Sergey; Pasanen, Pertti

    Biomodeling experiment was performed at the Institute of Biophysics in Krasnoyarsk dedicated to modeling the bacterial aerosol behavior in airtight chamber. The experiment was perform an one of workpackages of FP-7 project BIOSMHARS. Bacterial aerosol included particles of bacteria and fungi: Staphylococcus epidermidis, Bacillus licheniformis and Penicillium expansum The experiments allowed the following conclusions: 1. The major trend in air and surface contamination is permanent presence of the microbial factor throughout the time of generation. In the course of generation, level of contamination was gradually dropping except for the upward trend at the end of generation. These patterns were confirmed equally by the results of sedimentation studies and measurements using the Andersen impact 2. Sedimentation of airborne particles containing microbes went on at least two hours after the generation had been finished. However, level of this late sedimentation was approximately 10 folds less as compared with that in the course of generation. 3. Horizontal surfaces appear to be particularly vulnerable loci in airtight rooms. Their contamination was the highest. Levels of their contamination were higher than elsewhere. The closer is the source, the higher the level of contamination. 4. Walls were least contaminated. The ceiling was essentially clean. Air in the vicinity of the ceiling contained microbiota little if any. To summarize, the modeling experiments showed that the microbial component is a permanent resident of airtight rooms no matter decontamination effort (HEPA filters). The gravitational forces ensure that air cleans from microbiota by way of sedimentation. At the same time, together with microparticles microflora accumulates on horizontal surfaces which become the loci of microbes deposition and development. Therefore, despite the system of microbial control, risks of infection still raises the major concern for those who work in airtight facilities

  7. Accounting for microbial habitats in modeling soil organic matter dynamics

    Science.gov (United States)

    Chenu, Claire; Garnier, Patricia; Nunan, Naoise; Pot, Valérie; Raynaud, Xavier; Vieublé, Laure; Otten, Wilfred; Falconer, Ruth; Monga, Olivier

    2017-04-01

    The extreme heterogeneity of soils constituents, architecture and inhabitants at the microscopic scale is increasingly recognized. Microbial communities exist and are active in a complex 3-D physical framework of mineral and organic particles defining pores of various sizes, more or less inter-connected. This results in a frequent spatial disconnection between soil carbon, energy sources and the decomposer organisms and a variety of microhabitats that are more or less suitable for microbial growth and activity. However, current biogeochemical models account for C dynamics at the macroscale (cm, m) and consider time- and spatially averaged relationships between microbial activity and soil characteristics. Different modelling approaches have intended to account for this microscale heterogeneity, based either on considering aggregates as surrogates for microbial habitats, or pores. Innovative modelling approaches are based on an explicit representation of soil structure at the fine scale, i.e. at µm to mm scales: pore architecture and their saturation with water, localization of organic resources and of microorganisms. Three recent models are presented here, that describe the heterotrophic activity of either bacteria or fungi and are based upon different strategies to represent the complex soil pore system (Mosaic, LBios and µFun). These models allow to hierarchize factors of microbial activity in soil's heterogeneous architecture. Present limits of these approaches and challenges are presented, regarding the extensive information required on soils at the microscale and to up-scale microbial functioning from the pore to the core scale.

  8. Linking microbial diversity and functionality of arctic glacial surface habitats.

    Science.gov (United States)

    Lutz, Stefanie; Anesio, Alexandre M; Edwards, Arwyn; Benning, Liane G

    2017-02-01

    Distinct microbial habitats on glacial surfaces are dominated by snow and ice algae, which are the critical players and the dominant primary colonisers and net producers during the melt season. Here for the first time we have evaluated the role of these algae in association with the full microbial community composition (i.e., algae, bacteria, archaea) in distinct surface habitats and on 12 glaciers and permanent snow fields in Svalbard and Arctic Sweden. We cross-correlated these data with the analyses of specific metabolites such as fatty acids and pigments, and a full suite of potential critical physico-chemical parameters including major and minor nutrients, and trace metals. It has been shown that correlations between single algal species, metabolites, and specific geochemical parameters can be used to unravel mixed metabolic signals in complex communities, further assign them to single species and infer their functionality. The data also clearly show that the production of metabolites in snow and ice algae is driven mainly by nitrogen and less so by phosphorus limitation. This is especially important for the synthesis of secondary carotenoids, which cause a darkening of glacial surfaces leading to a decrease in surface albedo and eventually higher melting rates. © 2016 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  9. Volcano-ice interaction as a microbial habitat on Earth and Mars.

    Science.gov (United States)

    Cousins, Claire R; Crawford, Ian A

    2011-09-01

    Volcano-ice interaction has been a widespread geological process on Earth that continues to occur to the present day. The interaction between volcanic activity and ice can generate substantial quantities of liquid water, together with steep thermal and geochemical gradients typical of hydrothermal systems. Environments available for microbial colonization within glaciovolcanic systems are wide-ranging and include the basaltic lava edifice, subglacial caldera meltwater lakes, glacier caves, and subsurface hydrothermal systems. There is widespread evidence of putative volcano-ice interaction on Mars throughout its history and at a range of latitudes. Therefore, it is possible that life on Mars may have exploited these habitats, much in the same way as has been observed on Earth. The sedimentary and mineralogical deposits resulting from volcano-ice interaction have the potential to preserve evidence of any indigenous microbial populations. These include jökulhlaup (subglacial outflow) sedimentary deposits, hydrothermal mineral deposits, basaltic lava flows, and subglacial lacustrine deposits. Here, we briefly review the evidence for volcano-ice interactions on Mars and discuss the geomicrobiology of volcano-ice habitats on Earth. In addition, we explore the potential for the detection of these environments on Mars and any biosignatures these deposits may contain.

  10. Mapping Thermal Habitat of Ectotherms Based on Behavioral Thermoregulation in a Controlled Thermal Environment

    Science.gov (United States)

    Fei, T.; Skidmore, A.; Liu, Y.

    2012-07-01

    Thermal environment is especially important to ectotherm because a lot of physiological functions rely on the body temperature such as thermoregulation. The so-called behavioural thermoregulation function made use of the heterogeneity of the thermal properties within an individual's habitat to sustain the animal's physiological processes. This function links the spatial utilization and distribution of individual ectotherm with the thermal properties of habitat (thermal habitat). In this study we modelled the relationship between the two by a spatial explicit model that simulates the movements of a lizard in a controlled environment. The model incorporates a lizard's transient body temperatures with a cellular automaton algorithm as a way to link the physiology knowledge of the animal with the spatial utilization of its microhabitat. On a larger spatial scale, 'thermal roughness' of the habitat was defined and used to predict the habitat occupancy of the target species. The results showed the habitat occupancy can be modelled by the cellular automaton based algorithm at a smaller scale, and can be modelled by the thermal roughness index at a larger scale.

  11. A Novel Microbial Habitat in the Mid-Ocean Ridge Subseafloor

    National Research Council Canada - National Science Library

    Melanie Summit; John A. Baross

    2001-01-01

    The subseafloor at the mid-ocean ridge is predicted to be an excellent microbial habitat, because there is abundant space, fluid flow, and geochemical energy in the porous, hydrothermally influenced oceanic crust...

  12. Microbial Biosignatures in High Iron Thermal Springs

    Science.gov (United States)

    Parenteau, M. N.; Embaye, T.; Jahnke, L. L.; Cady, S. L.

    2003-12-01

    The emerging anoxic source waters at Chocolate Pots hot springs in Yellowstone National Park contain 2.6 to 11.2 mg/L Fe(II) and are 51-54° C and pH 5.5-6.0. These waters flow down the accumulating iron deposits and over three major phototrophic mat communities: Synechococcus/Chloroflexus at 51-54° C, Pseudanabaena at 51-54° C, and a narrow Oscillatoria at 36-45° C. We are assessing the contribution of the phototrophs to biosignature formation in this high iron system. These biosignatures can be used to assess the biological contribution to ancient iron deposits on Earth (e.g. Precambrian Banded Iron Formations) and, potentially, to those found on Mars. Most studies to date have focused on chemotrophic iron-oxidizing communities; however, recent research has demonstrated that phototrophs have a significant physiological impact on these iron thermal springs (Pierson et al. 1999, Pierson and Parenteau 2000, and Trouwborst et al., 2003). We completed a survey of the microfossils, biominerals, biofabrics, and lipid biomarkers in the phototrophic mats and stromatolitic iron deposits using scanning and transmission electron microscopy (SEM and TEM), energy dispersive spectrometry (EDS), powder X-ray diffraction (XRD), and gas chromatography-mass spectroscopy (GC-MS). The Synechococcus/Chloroflexus mat was heavily encrusted with iron silicates while the narrow Oscillatoria mat was encrusted primarily with iron oxides. Encrustation of the cells increased with depth in the mats. Amorphous 2-line ferrihydrite is the primary precipitate in the spring and the only iron oxide mineral associated with the mats. Goethite, hematite, and siderite were detected in dry sediment samples on the face of the main iron deposit. Analysis of polar lipid fatty acid methyl esters (FAME) generated a suite of lipid biomarkers. The Synechococcus/Chloroflexus mat contained two mono-unsaturated isomers of n-C18:1 with smaller amounts of polyunsaturated n-C18:2, characteristic of cyanobacteria

  13. Thermal ecology of three coexistent desert lizards: Implications for habitat divergence and thermal vulnerability.

    Science.gov (United States)

    Li, Shu-Ran; Wang, Yang; Ma, Liang; Zeng, Zhi-Gao; Bi, Jun-Huai; Du, Wei-Guo

    2017-10-01

    How ectotherms exploit thermal resources has important implications for their habitat utilization and thermal vulnerability to climate warming. To address this issue, we investigated thermal relations of three sympatric lizard species (Eremias argus, Eremias multiocellata, and Phrynocephalus przewalskii) in the desert steppe of Inner Mongolia, China. We determined the thermoregulatory behavior, body temperature (T b ), operative temperature (T e ), selected body temperature (T sel ), and critical thermal maximum (CT max ) of adult lizards. Based on these physiological parameters, we quantified the accuracy and effectiveness of thermoregulation as well as thermal-safety margin for these species. The three species were accurate and effective thermoregulators. The P. przewalskii preferred open habitats, and had a higher T b than the two Eremias lizards, which preferred shade habitats and shuttled more frequently between the shade and sun. This indicated that the three sympatric lizards have different thermoregulatory behavior and thermal physiology, which might facilitate their coexistence in the desert steppe ecosystem. In addition, the P. przewalskii had higher T sel and CT max , and a wider thermal-safety margin than the two Eremias lizards, suggesting that the two Eremias lizards would be more vulnerable to climate warming than P. przewalskii.

  14. Spatio temporal analysis of microbial habitats in soil-root interfaces

    Science.gov (United States)

    Eickhorst, Thilo; Schmidt, Hannes

    2017-04-01

    Microbial habitats in soils are formed by the arrangement and availability of inorganic and organic compounds. They can be characterized by physico-chemical parameters and the resulting colonization by microorganisms. Areas being preferably colonized are known as microbial hot spots which can be found in (bio)pores within the aggregatusphere or in the rhizosphere. The latter is directly influenced by plants i.e. the growth and activity of plant roots which has an influence on physico-chemical dynamics in the rhizosphere and can even shape plants' root microbiome. As microbial communities play an important role in nutrient cycling their response in soil-root interfaces is of great importance. Especially in complex systems such as paddy soils used for the cultivation of wetland rice the analysis of spatio-temporal aspects is important to get knowledge about their influence on the microbial dynamics in the respective habitats. But also other spatial variations on larger scales up to landscape scale may have an impact on the soil microorganisms in their habitats. This PICO presentation will introduce a set of techniques which are useful to analyze both the physico-chemical characteristics of microbial habitats and the microbial colonization and dynamics in soil-root interfaces. Examples will be given on various studies from rice cultivation in different paddy soils up to an European transect representing rhizosphere soils of selected plant species.

  15. Microbial community dynamics in Inferno Crater Lake, a thermally fluctuating geothermal spring.

    Science.gov (United States)

    Ward, Laura; Taylor, Michael W; Power, Jean F; Scott, Bradley J; McDonald, Ian R; Stott, Matthew B

    2017-05-01

    Understanding how microbial communities respond and adjust to ecosystem perturbation is often difficult to interpret due to multiple and often simultaneous variations in observed conditions. In this research, we investigated the microbial community dynamics of Inferno Crater Lake, an acidic geothermal spring in New Zealand with a unique thermal cycle that varies between 30 and 80 °C over a period of 40-60 days. Using a combination of next-generation sequencing, geochemical analysis and quantitative PCR we found that the microbial community composition was predominantly chemolithotrophic and strongly associated with the thermal cycle. At temperatures >65 °C, the microbial community was dominated almost exclusively by sulphur-oxidising archaea (Sulfolobus-like spp.). By contrast, at mesophilic temperatures the community structure was more mixed, comprising both archaea and bacteria but dominated primarily by chemolithotrophic sulphur and hydrogen oxidisers. Multivariate analysis of physicochemical data confirmed that temperature was the only significant variable associated with community turnover. This research contributes to our understanding of microbial community dynamics in variable environments, using a naturally alternating system as a model and extends our limited knowledge of acidophile ecology in geothermal habitats.

  16. Polar Basal Ice as Microbial Habitat, an Analog for Mars?

    Science.gov (United States)

    Skidmore, M. L.; Dore, J. E.; Lindsay, M.; Tunby, P.; Sletten, R. S.; Boyd, E. S.

    2016-09-01

    The physical, chemical, and biological properties of debris-rich ice sampled from the margin of the Greenland Ice Sheet will be described, its habitat potential evaluated, and its value as a possible test site for life detection tools discussed.

  17. Biodiversity and succession of microbial community in a multi-habitat membrane bioreactor.

    Science.gov (United States)

    Tang, Bing; Zhang, Zi; Chen, Xuan; Bin, Liying; Huang, Shaosong; Fu, Fenglian; Yang, Huiwen; Chen, Cuiqun

    2014-07-01

    The present study focused on establishing a multi-habitat membrane bioreactor, as well as exploring its biodiversity and succession of microbial communities. In a long-term operational period (100 days), the dissolved oxygen level of a local zone within the bioreactor decreased consistently from the original oxic state to the final anaerobic state, which led to a continuous succession of the microbial community in the bioreactor. The results revealed that the biodiversity of the microbial community in different zones simultaneously increased, with a similar microbial composition in their final successional stage. The results also indicated that the dominant species during the whole operation were distributed among 6 major phyla. At the initial operational stages, the dominant species in the anoxic-anaerobic and the oxic zones exhibited distinguished difference, whereas at the final operational stage, both zones presented nearly the same dominant microbial species and a rather similar structure in their microbial communities. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Microbial existence in controlled habitats and their resistance to space conditions.

    Science.gov (United States)

    Venkateswaran, Kasthuri; La Duc, Myron T; Horneck, Gerda

    2014-09-17

    The National Research Council (NRC) has recently recognized the International Space Station (ISS) as uniquely suitable for furthering the study of microbial species in closed habitats. Answering the NRC's call for the study, in particular, of uncommon microbial species in the ISS, and/or of those that have significantly increased or decreased in number, space microbiologists have begun capitalizing on the maturity, speed, and cost-effectiveness of molecular/genomic microbiological technologies to elucidate changes in microbial populations in the ISS and other closed habitats. Since investigators can only collect samples infrequently from the ISS itself due to logistical reasons, Earth analogs, such as spacecraft-assembly clean rooms, are used and extensively characterized for the presence of microbes. Microbiologists identify the predominant, problematic, and extremophilic microbial species in these closed habitats and use the ISS as a testbed to study their resistance to extreme extraterrestrial environmental conditions. Investigators monitor the microbes exposed to the real space conditions in order to track their genomic changes in response to the selective pressures present in outer space (external to the ISS) and the spaceflight (in the interior of the ISS). In this review, we discussed the presence of microbes in space research-related closed habitats and the resistance of some microbial species to the extreme environmental conditions of space.

  19. Synthetic Microbial Ecology: Engineering Habitats for Modular Consortia

    Directory of Open Access Journals (Sweden)

    Sami Ben Said

    2017-06-01

    Full Text Available The metabolic diversity present in microbial communities enables cooperation toward accomplishing more complex tasks than possible by a single organism. Members of a consortium communicate by exchanging metabolites or signals that allow them to coordinate their activity through division of labor. In contrast with monocultures, evidence suggests that microbial consortia self-organize to form spatial patterns, such as observed in biofilms or in soil aggregates, that enable them to respond to gradient, to improve resource interception and to exchange metabolites more effectively. Current biotechnological applications of microorganisms remain rudimentary, often relying on genetically engineered monocultures (e.g., pharmaceuticals or mixed-cultures of partially known composition (e.g., wastewater treatment, yet the vast potential of “microbial ecological power” observed in most natural environments, remains largely underused. In line with the Unified Microbiome Initiative (UMI which aims to “discover and advance tools to understand and harness the capabilities of Earth's microbial ecosystems,” we propose in this concept paper to capitalize on ecological insights into the spatial and modular design of interlinked microbial consortia that would overcome limitations of natural systems and attempt to optimize the functionality of the members and the performance of the engineered consortium. The topology of the spatial connections linking the various members and the regulated fluxes of media between those modules, while representing a major engineering challenge, would allow the microbial species to interact. The modularity of such spatially linked microbial consortia (SLMC could facilitate the design of scalable bioprocesses that can be incorporated as parts of a larger biochemical network. By reducing the need for a compatible growth environment for all species simultaneously, SLMC will dramatically expand the range of possible combinations of

  20. Microbial habitat dynamics and ablation control on the Ward Hunt Ice Shelf

    Science.gov (United States)

    Mueller, Derek R.; Vincent, Warwick F.

    2006-03-01

    The Ward Hunt Ice Shelf (83°02N, 74°00W) is an 40 m thick ice feature that occupies a large embayment along Canada's northernmost coast. Sediments cover 10% of its surface and provide a habitat for diverse microbial communities. These assemblages form an organo-sedimentary matrix (microbial mat) composed of cold-tolerant cyanobacteria and several other types of organisms. We investigated the environmental properties (temperature, irradiance, conductivity and nutrient concentration) of the microbial mat habitat and the effect of the microbial mats on the surface topography of the ice shelf. The low albedo of microbial mats relative to the surrounding snow and ice encouraged meltwater production, thereby extending the growth season to 61 days despite only 52 days with mean temperatures above 0 °C. We found large excursions in salinity near the microbial mat during freeze-up and melt, and 54% of all ponds sampled had conductivity profiles indicating stratification. Nutrient concentrations within the microbial mats were up to two orders of magnitude higher than those found in the water column, which underscores the differences between the microbial mat microenvironment and the overall bulk properties of the cryo-ecosystem. The average ice surface ablation in the microbial mat-rich study site was 1.22 m year-1, two times higher than values measured in areas of the ice shelf where mats were less prevalent. We demonstrate with topographic surveys that the microbial mats promote differential ablation and conclude that the cohesive microbial aggregates trap and stabilize sediment, reduce albedo, and thereby influence the surface morphology of the ice shelf.

  1. Habitat-associated phylogenetic community patterns of microbial ammonia oxidizers.

    Directory of Open Access Journals (Sweden)

    Antoni Fernàndez-Guerra

    Full Text Available Microorganisms mediating ammonia oxidation play a fundamental role in the connection between biological nitrogen fixation and anaerobic nitrogen losses. Bacteria and Archaea ammonia oxidizers (AOB and AOA, respectively have colonized similar habitats worldwide. Ammonia oxidation is the rate-limiting step in nitrification, and the ammonia monooxygenase (Amo is the key enzyme involved. The molecular ecology of this process has been extensively explored by surveying the gene of the subunit A of the Amo (amoA gene. In the present study, we explored the phylogenetic community ecology of AOB and AOA, analyzing 5776 amoA gene sequences from >300 isolation sources, and clustering habitats by environmental ontologies. As a whole, phylogenetic richness was larger in AOA than in AOB, and sediments contained the highest phylogenetic richness whereas marine plankton the lowest. We also observed that freshwater ammonia oxidizers were phylogenetically richer than their marine counterparts. AOA communities were more dissimilar to each other than those of AOB, and consistent monophyletic lineages were observed for sediments, soils, and marine plankton in AOA but not in AOB. The diversification patterns showed a more constant cladogenesis through time for AOB whereas AOA apparently experienced two fast diversification events separated by a long steady-state episode. The diversification rate (γ statistic for most of the habitats indicated γ(AOA > γ(AOB. Soil and sediment experienced earlier bursts of diversification whereas habitats usually eutrophic and rich in ammonium such as wastewater and sludge showed accelerated diversification rates towards the present. Overall, this work shows for the first time a global picture of the phylogenetic community structure of both AOB and AOA assemblages following the strictest analytical standards, and provides an ecological view on the differential evolutionary paths experienced by widespread ammonia

  2. Transfer of enteric pathogens to successive habitats as part of microbial cycles

    NARCIS (Netherlands)

    Semenov, A.M.; Kupriyanov, A.A.; Bruggen, van A.H.C.

    2010-01-01

    Escherichia coli O157:H7 gfp and Salmonella enterica Typhimurium gfp passed through six successive habitats within a microbial cycle. Pathogen cultures were introduced into cow dung or fodder. Microscopically observed cells and CFUs were monitored in fodder, dung, dung-soil mix, rhizosphere and

  3. A submarine volcanic eruption leads to a novel microbial habitat.

    Science.gov (United States)

    Danovaro, Roberto; Canals, Miquel; Tangherlini, Michael; Dell'Anno, Antonio; Gambi, Cristina; Lastras, Galderic; Amblas, David; Sanchez-Vidal, Anna; Frigola, Jaime; Calafat, Antoni M; Pedrosa-Pàmies, Rut; Rivera, Jesus; Rayo, Xavier; Corinaldesi, Cinzia

    2017-04-24

    Submarine volcanic eruptions are major catastrophic events that allow investigation of the colonization mechanisms of newly formed seabed. We explored the seafloor after the eruption of the Tagoro submarine volcano off El Hierro Island, Canary Archipelago. Near the summit of the volcanic cone, at about 130 m depth, we found massive mats of long, white filaments that we named Venus's hair. Microscopic and molecular analyses revealed that these filaments are made of bacterial trichomes enveloped within a sheath and colonized by epibiotic bacteria. Metagenomic analyses of the filaments identified a new genus and species of the order Thiotrichales, Thiolava veneris. Venus's hair shows an unprecedented array of metabolic pathways, spanning from the exploitation of organic and inorganic carbon released by volcanic degassing to the uptake of sulfur and nitrogen compounds. This unique metabolic plasticity provides key competitive advantages for the colonization of the new habitat created by the submarine eruption. A specialized and highly diverse food web thrives on the complex three-dimensional habitat formed by these microorganisms, providing evidence that Venus's hair can drive the restart of biological systems after submarine volcanic eruptions.

  4. The Microbial Signature Provides Insight into the Mechanistic Basis of Coral Success across Reef Habitats

    Directory of Open Access Journals (Sweden)

    Alejandra Hernandez-Agreda

    2016-07-01

    Full Text Available For ecosystems vulnerable to environmental change, understanding the spatiotemporal stability of functionally crucial symbioses is fundamental to determining the mechanisms by which these ecosystems may persist. The coral Pachyseris speciosa is a successful environmental generalist that succeeds in diverse reef habitats. The generalist nature of this coral suggests it may have the capacity to form functionally significant microbial partnerships to facilitate access to a range of nutritional sources within different habitats. Here, we propose that coral is a metaorganism hosting three functionally distinct microbial interactions: a ubiquitous core microbiome of very few symbiotic host-selected bacteria, a microbiome of spatially and/or regionally explicit core microbes filling functional niches (100,000 phylotypes. We find that this coral hosts upwards of 170,000 distinct phylotypes and provide evidence for the persistence of a select group of bacteria in corals across environmental habitats of the Great Barrier Reef and Coral Sea. We further show that a higher number of bacteria are consistently associated with corals on mesophotic reefs than on shallow reefs. An increase in microbial diversity with depth suggests reliance by this coral on bacteria for nutrient acquisition on reefs exposed to nutrient upwelling. Understanding the complex microbial communities of host organisms across broad biotic and abiotic environments as functionally distinct microbiomes can provide insight into those interactions that are ubiquitous niche symbioses and those that provide competitive advantage within the hosts’ environment.

  5. Build your own soil: exploring microfluidics to create microbial habitat structures.

    Science.gov (United States)

    Aleklett, Kristin; Kiers, E Toby; Ohlsson, Pelle; Shimizu, Thomas S; Caldas, Victor Ea; Hammer, Edith C

    2017-11-14

    Soil is likely the most complex ecosystem on earth. Despite the global importance and extraordinary diversity of soils, they have been notoriously challenging to study. We show how pioneering microfluidic techniques provide new ways of studying soil microbial ecology by allowing simulation and manipulation of chemical conditions and physical structures at the microscale in soil model habitats.The ISME Journal advance online publication, 14 November 2017; doi:10.1038/ismej.2017.184.

  6. Coping with temperature at the warm edge--patterns of thermal adaptation in the microbial eukaryote Paramecium caudatum.

    Science.gov (United States)

    Krenek, Sascha; Petzoldt, Thomas; Berendonk, Thomas U

    2012-01-01

    Ectothermic organisms are thought to be severely affected by global warming since their physiological performance is directly dependent on temperature. Latitudinal and temporal variations in mean temperatures force ectotherms to adapt to these complex environmental conditions. Studies investigating current patterns of thermal adaptation among populations of different latitudes allow a prediction of the potential impact of prospective increases in environmental temperatures on their fitness. In this study, temperature reaction norms were ascertained among 18 genetically defined, natural clones of the microbial eukaryote Paramecium caudatum. These different clones have been isolated from 12 freshwater habitats along a latitudinal transect in Europe and from 3 tropical habitats (Indonesia). The sensitivity to increasing temperatures was estimated through the analysis of clone specific thermal tolerances and by relating those to current and predicted temperature data of their natural habitats. All investigated European clones seem to be thermal generalists with a broad thermal tolerance and similar optimum temperatures. The weak or missing co-variation of thermal tolerance with latitude does not imply local adaptation to thermal gradients; it rather suggests adaptive phenotypic plasticity among the whole European subpopulation. The tested Indonesian clones appear to be locally adapted to the less variable, tropical temperature regime and show higher tolerance limits, but lower tolerance breadths. Due to the lack of local temperature adaptation within the European subpopulation, P. caudatum genotypes at the most southern edge of their geographic range seem to suffer from the predicted increase in magnitude and frequency of summer heat waves caused by climate change.

  7. In vitro anticancer activity of microbial isolates from diverse habitats

    Directory of Open Access Journals (Sweden)

    Angel Treasa Thomas

    2011-06-01

    Full Text Available Extracts from natural products, especially microorganisms, have served as a valuable source of diverse molecules in many drug discovery efforts and led to the discovery of several important drugs. Identification of microbial strains having promising biological activities and purifying the bio-molecules responsible for the activities, have led to the discovery of many bioactive molecules. Extracellular, as well as intracellular, extracts of the metabolites of thirty-six bacterial and twenty-four fungal isolates, grown under unusual conditions such as high temperature, high salt and low sugar concentrations, were in vitro tested for their cytotoxic potential on various cancer cell lines. The extracts were screened on HeLa and MCF-7 cell lines to study the cytotoxic potential. Nuclear staining and flow cytometric studies were carried out to assess the potential of the extracts in arresting the cell cycle. The crude ethylacetate extract of isolate F-21 showed promising results by MTT assay with IC50 as low as 20.37±0.36 µg/mL on HeLa, and 44.75±0.81 µg/mL on MCF-7 cells, comparable with Cisplatin. The isolate F-21 was identified as Aspergillus sp. Promising results were also obtained with B-2C and B-4E strains. Morphological studies, biochemical tests and preliminary chemical investigation of the extracts were also carried out.Extratos de produtos naturais, especialmente de microrganismos, constituíram-se em fonte valiosa de diversas moléculas em muitas descobertas de fármacos e levaram à descoberta de fármacos importantes. A identificação de espécies microbianas que apresentam atividade biológica e a purificação de biomoléculas responsáveis pelas atividades levou à descoberta de muitas moléculas bioativas. Extratos extracelulares tanto quanto intracelulares de metabólitos de 36 isolados de bactérias e 24 isolados de fungos, que cresceram sob condições não usuais, como alta temperatura, alta concentração de sal e baixa

  8. Microbial weeds in hypersaline habitats: the enigma of the weed-like Haloferax mediterranei

    Science.gov (United States)

    Oren, Aharon; Hallsworth, John E.

    2014-10-01

    Heterotrophic prokaryotic communities that inhabit saltern crystallizer ponds are typically dominated by two species, the archaeon Haloquadratum walsbyi and the bacterium Salinibacter ruber, regardless of location. These organisms behave as 'microbial weeds' as defined by Cray et al. (Microb Biotechnol6: 453–492, 2013) that possess the biological traits required to dominate the microbiology of these open habitats. Here, we discuss the enigma of the less abundant Haloferax mediterranei, an archaeon that grows faster than any other, comparable extreme halophile. It has a wide window for salt tolerance, can grow on simple as well as on complex substrates and degrade polymeric substances, has different modes of anaerobic growth, can accumulate storage polymers, produces gas vesicles, and excretes halocins capable of killing other Archaea. Therefore, Hfx. mediterranei is apparently more qualified as a 'microbial weed' than Haloquadratum and Salinibacter. However, the former differs because it produces carotenoid pigments only in the lower salinity range and lacks energy-generating retinal-based, light-driven ion pumps such as bacteriorhodopsin and halorhodopsin. We discuss these observations in relation to microbial weed biology in, and the open-habitat ecology of, hypersaline systems.

  9. Habitat Fragmentation can Modulate Drought Effects on the Plant-soil-microbial System in Mediterranean Holm Oak (Quercus ilex) Forests.

    Science.gov (United States)

    Flores-Rentería, Dulce; Curiel Yuste, Jorge; Rincón, Ana; Brearley, Francis Q; García-Gil, Juan Carlos; Valladares, Fernando

    2015-05-01

    Ecological transformations derived from habitat fragmentation have led to increased threats to above-ground biodiversity. However, the impacts of forest fragmentation on soils and their microbial communities are not well understood. We examined the effects of contrasting fragment sizes on the structure and functioning of soil microbial communities from holm oak forest patches in two bioclimatically different regions of Spain. We used a microcosm approach to simulate the annual summer drought cycle and first autumn rainfall (rewetting), evaluating the functional response of a plant-soil-microbial system. Forest fragment size had a significant effect on physicochemical characteristics and microbial functioning of soils, although the diversity and structure of microbial communities were not affected. The response of our plant-soil-microbial systems to drought was strongly modulated by the bioclimatic conditions and the fragment size from where the soils were obtained. Decreasing fragment size modulated the effects of drought by improving local environmental conditions with higher water and nutrient availability. However, this modulation was stronger for plant-soil-microbial systems built with soils from the northern region (colder and wetter) than for those built with soils from the southern region (warmer and drier) suggesting that the responsiveness of the soil-plant-microbial system to habitat fragmentation was strongly dependent on both the physicochemical characteristics of soils and the historical adaptation of soil microbial communities to specific bioclimatic conditions. This interaction challenges our understanding of future global change scenarios in Mediterranean ecosystems involving drier conditions and increased frequency of forest fragmentation.

  10. Thermoregulatory strategies in an aquatic ectotherm from thermally-constrained habitats: An evaluation of current approaches.

    Science.gov (United States)

    Piasečná, Karin; Pončová, Alena; Tejedo, Miguel; Gvoždík, Lumír

    2015-08-01

    Many ectotherms employ diverse behavioral adjustments to effectively buffer the spatio-temporal variation in environmental temperatures, whereas others remain passive to thermal heterogeneity. Thermoregulatory studies are frequently performed on species living in thermally benign habitats, which complicate understanding of the thermoregulation-thermoconformity continuum. The need for new empirical data from ectotherms exposed to thermally challenging conditions requires the evaluation of available methods for quantifying thermoregulatory strategies. We evaluated the applicability of various thermoregulatory indices using fire salamander larvae, Salamandra salamandra, in two aquatic habitats, a forest pool and well, as examples of disparate thermally-constrained environments. Water temperatures in the well were lower and less variable than in the pool. Thermal conditions prevented larvae from reaching their preferred body temperature range in both water bodies. In contrast to their thermoregulatory abilities examined in a laboratory thermal gradient, field body temperatures only matched the mean and range of operative temperatures, showing thermal passivity of larvae in both habitats. Despite apparent thermoconformity, thermoregulatory indices indicated various strategies from active thermoregulation, to thermoconformity, and even thermal evasion, which revealed their limited applicability under thermally-constrained conditions. Salamander larvae abandoned behavioral thermoregulation despite varying opportunities to increase their body temperature above average water temperatures. Thermoconformity represents a favored strategy in these ectotherms living in more thermally-constrained environments than those examined in previous thermoregulatory studies. To understand thermal ecology and its impact on population dynamics, the quantification of thermoregulatory strategies of ectotherms in thermally-constrained habitats requires the careful choice of an appropriate

  11. Protistan microbial observatory in the Cariaco Basin, Caribbean. II. Habitat specialization.

    Science.gov (United States)

    Orsi, William; Edgcomb, Virginia; Jeon, Sunok; Leslin, Chesley; Bunge, John; Taylor, Gordon T; Varela, Ramon; Epstein, Slava

    2011-08-01

    This is the second paper in a series of three that investigates eukaryotic microbial diversity and taxon distribution in the Cariaco Basin, Venezuela, the ocean's largest anoxic marine basin. Here, we use phylogenetic information, multivariate community analyses and statistical richness predictions to test whether protists exhibit habitat specialization within defined geochemical layers of the water column. We also analyze spatio-temporal distributions of protists across two seasons and two geographic sites within the basin. Non-metric multidimensional scaling indicates that these two basin sites are inhabited by distinct protistan assemblages, an observation that is supported by the minimal overlap in observed and predicted richness of sampled sites. A comparison of parametric richness estimations indicates that protistan communities in closely spaced-but geochemically different-habitats are very dissimilar, and may share as few as 5% of total operational taxonomic units (OTUs). This is supported by a canonical correspondence analysis, indicating that the empirically observed OTUs are organized along opposing gradients in oxidants and reductants. Our phylogenetic analyses identify many new clades at species to class levels, some of which appear restricted to specific layers of the water column and have a significantly nonrandom distribution. These findings suggest many pelagic protists are restricted to specific habitats, and likely diversify, at least in part due to separation by geochemical barriers.

  12. Coping with temperature at the warm edge--patterns of thermal adaptation in the microbial eukaryote Paramecium caudatum.

    Directory of Open Access Journals (Sweden)

    Sascha Krenek

    Full Text Available BACKGROUND: Ectothermic organisms are thought to be severely affected by global warming since their physiological performance is directly dependent on temperature. Latitudinal and temporal variations in mean temperatures force ectotherms to adapt to these complex environmental conditions. Studies investigating current patterns of thermal adaptation among populations of different latitudes allow a prediction of the potential impact of prospective increases in environmental temperatures on their fitness. METHODOLOGY/PRINCIPAL FINDINGS: In this study, temperature reaction norms were ascertained among 18 genetically defined, natural clones of the microbial eukaryote Paramecium caudatum. These different clones have been isolated from 12 freshwater habitats along a latitudinal transect in Europe and from 3 tropical habitats (Indonesia. The sensitivity to increasing temperatures was estimated through the analysis of clone specific thermal tolerances and by relating those to current and predicted temperature data of their natural habitats. All investigated European clones seem to be thermal generalists with a broad thermal tolerance and similar optimum temperatures. The weak or missing co-variation of thermal tolerance with latitude does not imply local adaptation to thermal gradients; it rather suggests adaptive phenotypic plasticity among the whole European subpopulation. The tested Indonesian clones appear to be locally adapted to the less variable, tropical temperature regime and show higher tolerance limits, but lower tolerance breadths. CONCLUSIONS/SIGNIFICANCE: Due to the lack of local temperature adaptation within the European subpopulation, P. caudatum genotypes at the most southern edge of their geographic range seem to suffer from the predicted increase in magnitude and frequency of summer heat waves caused by climate change.

  13. Coping with Temperature at the Warm Edge – Patterns of Thermal Adaptation in the Microbial Eukaryote Paramecium caudatum

    Science.gov (United States)

    Krenek, Sascha; Petzoldt, Thomas; Berendonk, Thomas U.

    2012-01-01

    Background Ectothermic organisms are thought to be severely affected by global warming since their physiological performance is directly dependent on temperature. Latitudinal and temporal variations in mean temperatures force ectotherms to adapt to these complex environmental conditions. Studies investigating current patterns of thermal adaptation among populations of different latitudes allow a prediction of the potential impact of prospective increases in environmental temperatures on their fitness. Methodology/Principal Findings In this study, temperature reaction norms were ascertained among 18 genetically defined, natural clones of the microbial eukaryote Paramecium caudatum. These different clones have been isolated from 12 freshwater habitats along a latitudinal transect in Europe and from 3 tropical habitats (Indonesia). The sensitivity to increasing temperatures was estimated through the analysis of clone specific thermal tolerances and by relating those to current and predicted temperature data of their natural habitats. All investigated European clones seem to be thermal generalists with a broad thermal tolerance and similar optimum temperatures. The weak or missing co-variation of thermal tolerance with latitude does not imply local adaptation to thermal gradients; it rather suggests adaptive phenotypic plasticity among the whole European subpopulation. The tested Indonesian clones appear to be locally adapted to the less variable, tropical temperature regime and show higher tolerance limits, but lower tolerance breadths. Conclusions/Significance Due to the lack of local temperature adaptation within the European subpopulation, P. caudatum genotypes at the most southern edge of their geographic range seem to suffer from the predicted increase in magnitude and frequency of summer heat waves caused by climate change. PMID:22427799

  14. Climate change expands the spatial extent and duration of preferred thermal habitat for lake Superior fishes.

    Directory of Open Access Journals (Sweden)

    Timothy J Cline

    Full Text Available Climate change is expected to alter species distributions and habitat suitability across the globe. Understanding these shifting distributions is critical for adaptive resource management. The role of temperature in fish habitat and energetics is well established and can be used to evaluate climate change effects on habitat distributions and food web interactions. Lake Superior water temperatures are rising rapidly in response to climate change and this is likely influencing species distributions and interactions. We use a three-dimensional hydrodynamic model that captures temperature changes in Lake Superior over the last 3 decades to investigate shifts in habitat size and duration of preferred temperatures for four different fishes. We evaluated habitat changes in two native lake trout (Salvelinus namaycush ecotypes, siscowet and lean lake trout, Chinook salmon (Oncorhynchus tshawytscha, and walleye (Sander vitreus. Between 1979 and 2006, days with available preferred thermal habitat increased at a mean rate of 6, 7, and 5 days per decade for lean lake trout, Chinook salmon, and walleye, respectively. Siscowet lake trout lost 3 days per decade. Consequently, preferred habitat spatial extents increased at a rate of 579, 495 and 419 km(2 per year for the lean lake trout, Chinook salmon, and walleye while siscowet lost 161 km(2 per year during the modeled period. Habitat increases could lead to increased growth and production for three of the four fishes. Consequently, greater habitat overlap may intensify interguild competition and food web interactions. Loss of cold-water habitat for siscowet, having the coldest thermal preference, could forecast potential changes from continued warming. Additionally, continued warming may render more suitable conditions for some invasive species.

  15. Climate change expands the spatial extent and duration of preferred thermal habitat for lake Superior fishes.

    Science.gov (United States)

    Cline, Timothy J; Bennington, Val; Kitchell, James F

    2013-01-01

    Climate change is expected to alter species distributions and habitat suitability across the globe. Understanding these shifting distributions is critical for adaptive resource management. The role of temperature in fish habitat and energetics is well established and can be used to evaluate climate change effects on habitat distributions and food web interactions. Lake Superior water temperatures are rising rapidly in response to climate change and this is likely influencing species distributions and interactions. We use a three-dimensional hydrodynamic model that captures temperature changes in Lake Superior over the last 3 decades to investigate shifts in habitat size and duration of preferred temperatures for four different fishes. We evaluated habitat changes in two native lake trout (Salvelinus namaycush) ecotypes, siscowet and lean lake trout, Chinook salmon (Oncorhynchus tshawytscha), and walleye (Sander vitreus). Between 1979 and 2006, days with available preferred thermal habitat increased at a mean rate of 6, 7, and 5 days per decade for lean lake trout, Chinook salmon, and walleye, respectively. Siscowet lake trout lost 3 days per decade. Consequently, preferred habitat spatial extents increased at a rate of 579, 495 and 419 km(2) per year for the lean lake trout, Chinook salmon, and walleye while siscowet lost 161 km(2) per year during the modeled period. Habitat increases could lead to increased growth and production for three of the four fishes. Consequently, greater habitat overlap may intensify interguild competition and food web interactions. Loss of cold-water habitat for siscowet, having the coldest thermal preference, could forecast potential changes from continued warming. Additionally, continued warming may render more suitable conditions for some invasive species.

  16. Metaproteomic survey of six aquatic habitats: discovering the identities of microbial populations active in biogeochemical cycling.

    Science.gov (United States)

    Hanson, Buck T; Hewson, Ian; Madsen, Eugene L

    2014-04-01

    Our goal is to strengthen the foundations of metaproteomics as a microbial community analysis tool that links the functional identity of actively expressed gene products with host phylogeny. We used shotgun metaproteomics to survey waters in six disparate aquatic habitats (Cayuga Lake, NY; Oneida Lake, NY; Gulf of Maine; Chesapeake Bay, MD; Gulf of Mexico; and the South Pacific). Peptide pools prepared from filter-gathered microbial biomass, analyzed by nano-liquid chromatography-mass spectrometry (MS/MS) generating 9,693 ± 1,073 mass spectra identified 326 ± 107 bacterial proteins per sample. Distribution of proteobacterial (Alpha and Beta) and cyanobacterial (Prochlorococcus and Synechococcus spp.) protein hosts across all six samples was consistent with the previously published biogeography for these microorganisms. Marine samples were enriched in transport proteins (TRAP-type for dicarboxylates and ATP binding cassette (ABC)-type for amino acids and carbohydrates) compared with the freshwater samples. We were able to match in situ expression of many key proteins catalyzing C-, N-, and S-cycle processes with their bacterial hosts across all six habitats. Pelagibacter was identified as the host of ABC-type sugar-, organic polyanion-, and glycine betaine-transport proteins; this extends previously published studies of Pelagibacter's in situ biogeochemical role in marine C- and N-metabolism. Proteins matched to Ruegeria confirmed these organism's role in marine waters oxidizing both carbon monoxide and sulfide. By documenting both processes expressed in situ and the identity of host cells, metaproteomics tested several existing hypotheses about ecophysiological processes and provided fodder for new ones.

  17. Living at the Limits: Evidence for Microbial Eukaryotes Thriving under Pressure in Deep Anoxic, Hypersaline Habitats

    Directory of Open Access Journals (Sweden)

    Thorsten Stoeck

    2014-01-01

    Full Text Available The advent of molecular tools in microbial ecology paved the way to exploit the diversity of microbes in extreme environments. Here, we review these tools as applied in one of the most polyextreme habitats known on our planet, namely, deep hypersaline anoxic basins (DHABs, located at ca. 3000–3500 m depth in the Eastern Mediterranean Sea. Molecular gene signatures amplified from environmental DHAB samples identified a high degree of genetic novelty, as well as distinct communities in the DHABs. Canonical correspondence analyses provided strong evidence that salinity, ion composition, and anoxia were the strongest selection factors shaping protistan community structures, largely preventing cross-colonization among the individual basins. Thus, each investigated basin represents a unique habitat (“isolated islands of evolution”, making DHABs ideal model sites to test evolutionary hypotheses. Fluorescence in situ hybridization assays using specifically designed probes revealed that the obtained genetic signatures indeed originated from indigenous polyextremophiles. Electron microscopy imaging revealed unknown ciliates densely covered with prokaryote ectosymbionts, which may enable adaptations of eukaryotes to DHAB conditions. The research reviewed here significantly advanced our knowledge on polyextremophile eukaryotes, which are excellent models for a number of biological research areas, including ecology, diversity, biotechnology, evolutionary research, physiology, and astrobiology.

  18. A subzero microbial habitat in the basal ice of an Antarctic glacier (Invited)

    Science.gov (United States)

    Christner, B. C.; Doyle, S. M.; Montross, S. N.; Skidmore, M. L.; Samyn, D.; Lorrain, R.; Tison, J.; Fitzsimons, S.

    2010-12-01

    their ability to remain metabolically active under laboratory conditions to temperatures of -15oC. Together, the geochemical and biological data are in support of microbial respiration occurring in situ within the basal ice matrix at ambient temperatures of ~ -15oC, the current basal ice temperature. Due to the melting and refreezing of water, the basal zone of glaciers and ice sheets represents an important transient phase in the subglacial environment and is likely to have an important role in transporting viable microbial inocula and nutrients at the glacier bed. Furthermore, our results support the working hypothesis that the sediment-laden basal ice of cold-based ice sheets represents a distinct subzero microbial habitat in the subglacial environment.

  19. Implications of Extracellular Polymeric Substance Matrices of Microbial Habitats Associated with Coastal Aquaculture Systems

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    Juan Carlos Camacho-Chab

    2016-08-01

    Full Text Available Coastal zones support fisheries that provide food for humans and feed for animals. The decline of fisheries worldwide has fostered the development of aquaculture. Recent research has shown that extracellular polymeric substances (EPS synthesized by microorganisms contribute to sustainable aquaculture production, providing feed to the cultured species, removing waste and contributing to the hygiene of closed systems. As ubiquitous components of coastal microbial habitats at the air–seawater and seawater–sediment interfaces as well as of biofilms and microbial aggregates, EPS mediate deleterious processes that affect the performance and productivity of aquaculture facilities, including biofouling of marine cages, bioaccumulation and transport of pollutants. These biomolecules may also contribute to the persistence of harmful algal blooms (HABs and their impact on cultured species. EPS may also exert a positive influence on aquaculture activity by enhancing the settling of aquaculturally valuable larvae and treating wastes in bioflocculation processes. EPS display properties that may have biotechnological applications in the aquaculture industry as antiviral agents and immunostimulants and as a novel source of antifouling bioproducts.

  20. Multiscale thermal refugia and stream habitat associations of chinook salmon in northwestern Oregon

    Science.gov (United States)

    Torgersen, Christian E.; Price, David M.; Li, Hiram W.; McIntosh, B.A.

    1999-01-01

    We quantified distribution and behavior of adult spring chinook salmon (Oncorhynchus tshawytscha) related to patterns of stream temperature and physical habitat at channel-unit, reach-, and section-level spatial scales in a wilderness stream and a disturbed stream in the John Day River basin in northeastern Oregon. We investigated the effectiveness of thermal remote sensing for analyzing spatial patterns of stream temperature and assessed habitat selection by spring chinook salmon, evaluating whether thermal refugia might be responsible for the persistence of these stocks in rivers where water temperatures frequently exceed their upper tolerance levels (25A?C) during spawning migration. By presenting stream temperature and the ecology of chinook salmon in a historical context, we could evaluate how changes in riverine habitat and thermal spatial structure, which can be caused by land-use practices, may influence distributional patterns of chinook salmon. Thermal remote sensing provided spatially continuous maps of stream temperature for reaches used by chinook salmon in the upper subbasins of the Middle Fork and North Fork John Day River. Electivity analysis and logistic regression were used to test for associations between the longitudinal distribution of salmon and cool-water areas and stream habitat characteristics. Chinook salmon were distributed nonuniformly in reaches throughout each stream. Salmon distribution and cool water temperature patterns were most strongly related at reach-level spatial scales in the warm stream, the Middle Fork (maximum likelihood ratio: P 0.30). Pools were preferred by adult chinook salmon in both subbasins (Bonferroni confidence interval: P a?? 0.05); however, riffles were used proportionately more frequently in the North Fork than in the Middle Fork. Our observations of thermal refugia and their use by chinook salmon at multiple spatial scales reveal that, although heterogeneity in the longitudinal stream temperature profile may

  1. Global streamflow and thermal habitats of freshwater fishes under climate change

    NARCIS (Netherlands)

    Vliet, van M.T.H.; Ludwig, F.; Kabat, P.

    2013-01-01

    Climate change will affect future flow and thermal regimes of rivers. This will directly affect freshwater habitats and ecosystem health. In particular fish species, which are strongly adapted to a certain level of flow variability will be sensitive to future changes in flow regime. In addition, all

  2. Microbial habitat connectivity across spatial scales and hydrothermal temperature gradients at Guaymas Basin.

    Science.gov (United States)

    Meyer, Stefanie; Wegener, Gunter; Lloyd, Karen G; Teske, Andreas; Boetius, Antje; Ramette, Alban

    2013-01-01

    The Guaymas Basin (Gulf of California) hydrothermal vent area is known as a dynamic and hydrothermally vented sedimentary system, where the advection and production of a variety of different metabolic substrates support a high microbial diversity and activity in the seafloor. The main objective of our study was to explore the role of temperature and other environmental factors on community diversity, such as the presence of microbial mats and seafloor bathymetry within one hydrothermally vented field of 200 × 250 m dimension. In this field, temperature increased strongly with sediment depth reaching the known limit of life within a few decimeters. Potential sulfate reduction rate as a key community activity parameter was strongly affected by in situ temperature and sediment depth, declining from high rates of 1-5 μmol ml(-1) d(-1) at the surface to the detection limit below 5 cm sediment depth, despite the presence of sulfate and hydrocarbons. Automated Ribosomal Intergenic Spacer Analysis yielded a high-resolution fingerprint of the dominant members of the bacterial community. Our analyses showed strong temperature and sediment depth effects on bacterial cell abundance and Operational Taxonomic Units (OTUs) number, both declining by more than one order of magnitude below the top 5 cm of the sediment surface. Another fraction of the variation in diversity and community structure was explained by differences in the local bathymetry and spatial position within the vent field. Nevertheless, more than 80% of all detected OTUs were shared among the different temperature realms and sediment depths, after being classified as cold (T bacterial habitats in this dynamic and heterogeneous marine ecosystem influenced by strong hydrothermalism.

  3. Microbial habitat connectivity across spatial scales and hydrothermal temperature gradients at Guaymas Basin

    Directory of Open Access Journals (Sweden)

    Stefanie eMeyer

    2013-07-01

    Full Text Available The Guaymas Basin (Gulf of California hydrothermal vent area is known as a dynamic and hydrothermally vented sedimentary system, where the advection and production of a variety of different metabolic substrates support a high microbial diversity and activity in the seafloor. The main objective of our study was to explore the role of temperature and other environmental factors on community diversity, such as the presence of microbial mats and seafloor bathymetry within one hydrothermally vented field of 200 × 250 m dimension. In this field, temperature increased strongly with sediment depth reaching the known limit to life within a few decimeters. Potential sulfate reduction rate as a key community activity parameter was strongly affected by in situ temperature and sediment depth, declining from high rates of 1-5 μmol ml-1 d-1 at the surface to the detection limit below 5 cm sediment depth, despite the presence of sulfate and hydrocarbons. Automated Ribosomal Intergenic Spacer Analysis yielded a high-resolution fingerprint of the dominant members of the bacterial community. Our analyses showed strong temperature and sediment depth effects on bacterial cell abundance and Operational Taxonomic Units (OTUs number, both declining by more than one order of magnitude below the top 5 cm of the sediment surface. Another fraction of the variation in diversity and community structure was explained by differences in the local bathymetry and spatial position within the vent field. Nevertheless, more than 80% of all detected OTUs were shared among the different temperature realms and sediment depths, after being classified as cold (T<10°C, medium (10°C≤T<40°C or hot (T≥40°C temperature conditions, with significant OTU overlap with the richer surface communities. Overall, this indicates a high connectivity of benthic bacterial habitats in this dynamic and heterogeneous marine ecosystem influenced by strong hydrothermalism.

  4. Microbial Biofilm Community Variation in Flowing Habitats: Potential Utility as Bioindicators of Postmortem Submersion Intervals

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    Jennifer M. Lang

    2016-01-01

    Full Text Available Biofilms are a ubiquitous formation of microbial communities found on surfaces in aqueous environments. These structures have been investigated as biomonitoring indicators for stream heath, and here were used for the potential use in forensic sciences. Biofilm successional development has been proposed as a method to determine the postmortem submersion interval (PMSI of remains because there are no standard methods for estimating the PMSI and biofilms are ubiquitous in aquatic habitats. We sought to compare the development of epinecrotic (biofilms on Sus scrofa domesticus carcasses and epilithic (biofilms on unglazed ceramic tiles communities in two small streams using bacterial automated ribosomal intergenic spacer analysis. Epinecrotic communities were significantly different from epilithic communities even though environmental factors associated with each stream location also had a significant influence on biofilm structure. All communities at both locations exhibited significant succession suggesting that changing communities throughout time is a general characteristic of stream biofilm communities. The implications resulting from this work are that epinecrotic communities have distinctive shifts at the first and second weeks, and therefore the potential to be used in forensic applications by associating successional changes with submersion time to estimate a PMSI. The influence of environmental factors, however, indicates the lack of a successional pattern with the same organisms and a focus on functional diversity may be more applicable in a forensic context.

  5. Interplay between habitat fragmentation and climate change : inbreeding affects the response to thermal stress in Drosophila melanogaster

    NARCIS (Netherlands)

    Joubert, D.; Bijlsma, R.

    2010-01-01

    Climate change, exerting thermal stress, and habitat destruction and fragmentation, resulting in genetic drift and inbreeding, are amongst the most disturbing human activities that endanger global biodiversity. We studied the interplay between these 2 processes using Drosophila melanogaster as a

  6. Microbial structures in an Alpine Thermal Spring - Microscopic techniques for the examination of Biofilms in a Subsurface Environment

    Science.gov (United States)

    Dornmayr-Pfaffenhuemer, Marion; Pierson, Elisabeth; Janssen, Geert-Jan; Stan-Lotter, Helga

    2010-05-01

    suggest that the thermal springs in the Central Alps near Bad Gastein represent a novel and unique habitat for microbial life. Results obtained during these studies revealed reproducibility of Dr. Heinen's micrographs. Hollow reticulated filaments and flat ribbons with parallel hexagonal chambers (web-structures) were found repeatedly. Given the chance that subsurface environments represent a potent opportunity to detect life on planetary bodies it is of big interest to search for representative biosignatures found on earth today. References: 1. Lauwers A. M. & Heinen W. (1985) Mikroskopie (Wien) 42, 94-101. 2. Heinen W. & Lauwers A. M. (1985) Mikroskopie (Wien) 42, 124-134. 3. Weidler G. W., Dornmayr-Pfaffenhuemer M., Gerbl F. W., Heinen W., Stan-Lotter H. (2007) AEM 73, 259-270.

  7. Microbial community diversity, function, and succession in California’s Mediterranean habitats

    OpenAIRE

    Curd, Emily Elizabeth

    2016-01-01

    We live on a predominantly microbial planet. I it is estimated that more than a billion microorganisms can live in a gram of soil. Microorganisms comprise the largest pool of genetic diversity on the planet and drive global biogeochemical cycles. Since microbial ecology is intimately associated with environment, changes in environmental conditions can have profound effects on the microbial diversity and function of microbial communities. In this dissertation I study; 1) the relationship betw...

  8. Winter activity of terrestrial isopods from thermal habitats in western Romania

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    Ferenţi Sára

    2013-01-01

    Full Text Available Terrestrial isopods from warm shores neighboring the thermal waters from western Romania remain active in the winter. This phenomenon is registered in 35 habitats, affecting 12 species (Hyloniscus transsilvanicus, H. riparius, Haplophthalmus danicus, Trichoniscus sp., Androniscus roseus, Cylisticus convexus, Protracheoniscus politus, Trachelipus nodulosus, T. rathkii, Porcellio dilatatus, Armadillidium vulgare, A. versicolor, the most common being T. nodulosus. Females with a marsupium were observed in the cold season in the case of some small-sized species that are present in the immediate vicinity of the shores of thermal waters (A. roseus, H. riparius and H. transsilvanicus. The high temperatures of the thermal waters warm the surrounding terrestrial environment, affecting the life cycle of the terrestrial isopods.

  9. Differential thermal performance curves in response to different habitats in the parasitoid Venturia canescens

    Science.gov (United States)

    Foray, Vincent; Gibert, Patricia; Desouhant, Emmanuel

    2011-08-01

    Environmental variability is expected to be important in shaping performance curves, reaction norms of phenotypic traits related to fitness. Models predict that the breadth of performance curves should increase with environmental variability at the expense of maximal performance. In this study, we compared the thermal performance curves of two sympatric populations of the parasitoid Venturia canescens that were observed under contrasting thermal regimes in their respective preferred habitats and differing in their modes of reproduction. Our results confirm the large effect of developmental temperature on phenotypic traits of insects and demonstrate that thelytokous and arrhenotokous wasps respond differently to temperature during development, in agreement with model predictions. For traits related to fecundity, thelytokous parasitoids, which usually occur in stable thermal conditions, exhibit specialist performance curves, maximising their reproductive success under a restricted range of temperature. In contrast, arrhenotokous parasitoids, which occur in variable climates, exhibit generalist performance curves, in keeping with the hypothesis "jack of all temperatures, master of none".

  10. Colonization Habitat Controls Biomass, Composition, and Metabolic Activity of Attached Microbial Communities in the Columbia River Hyporheic Corridor

    Energy Technology Data Exchange (ETDEWEB)

    Stern, Noah; Ginder-Vogel, Matthew; Stegen, James C.; Arntzen, Evan; Kennedy, David W.; Larget, Bret R.; Roden, Eric E.; Kostka, Joel E.

    2017-06-09

    Hydrologic exchange plays a critical role in biogeochemical cycling within the hyporheic zone (the interface between river water and groundwater) of riverine ecosystems. Such exchange may set limits on the rates of microbial metabolism and impose deterministic selection on microbial communities that adapt to dynamically changing dissolved organic carbon (DOC) sources. This study examined the response of attached microbial communities (in situcolonized sand packs) from groundwater, hyporheic, and riverbed habitats within the Columbia River hyporheic corridor to “cross-feeding” with either groundwater, river water, or DOC-free artificial fluids. Our working hypothesis was that deterministic selection duringin situcolonization would dictate the response to cross-feeding, with communities displaying maximal biomass and respiration when supplied with their native fluid source. In contrast to expectations, the major observation was that the riverbed colonized sand had much higher biomass and respiratory activity, as well as a distinct community structure, compared with those of the hyporheic and groundwater colonized sands. 16S rRNA gene amplicon sequencing revealed a much higher proportion of certain heterotrophic taxa as well as significant numbers of eukaryotic algal chloroplasts in the riverbed colonized sand. Significant quantities of DOC were released from riverbed sediment and colonized sand, and separate experiments showed that the released DOC stimulated respiration in the groundwater and piezometer colonized sand. These results suggest that the accumulation and degradation of labile particulate organic carbon (POC) within the riverbed are likely to release DOC, which may enter the hyporheic corridor during hydrologic exchange, thereby stimulating microbial activity and imposing deterministic selective pressure on the microbial community composition.

    IMPORTANCEThe influence of river water

  11. Brook trout use of thermal refugia and foraging habitat influenced by brown trout

    Science.gov (United States)

    Hitt, Nathaniel P.; Snook, Erin; Massie, Danielle L.

    2017-01-01

    The distribution of native brook trout (Salvelinus fontinalis) in eastern North America is often limited by temperature and introduced brown trout (Salmo trutta), the relative importance of which is poorly understood but critical for conservation and restoration planning. We evaluated effects of brown trout on brook trout behavior and habitat use in experimental streams across increasing temperatures (14–23 °C) with simulated groundwater upwelling zones providing thermal refugia (6–9 °C below ambient temperatures). Allopatric and sympatric trout populations increased their use of upwelling zones as ambient temperatures increased, demonstrating the importance of groundwater as thermal refugia in warming streams. Allopatric brook trout showed greater movement rates and more even spatial distributions within streams than sympatric brook trout, suggesting interference competition by brown trout for access to forage habitats located outside thermal refugia. Our results indicate that removal of introduced brown trout may facilitate native brook trout expansion and population viability in downstream reaches depending in part on the spatial configuration of groundwater upwelling zones.

  12. Microhabitat selection by marine mesoconsumers in a thermally heterogeneous habitat: behavioral thermoregulation or avoiding predation risk?

    Directory of Open Access Journals (Sweden)

    Jeremy J Vaudo

    Full Text Available Habitat selection decisions by consumers has the potential to shape ecosystems. Understanding the factors that influence habitat selection is therefore critical to understanding ecosystem function. This is especially true of mesoconsumers because they provide the link between upper and lower tropic levels. We examined the factors influencing microhabitat selection of marine mesoconsumers - juvenile giant shovelnose rays (Glaucostegus typus, reticulate whiprays (Himantura uarnak, and pink whiprays (H. fai - in a coastal ecosystem with intact predator and prey populations and marked spatial and temporal thermal heterogeneity. Using a combination of belt transects and data on water temperature, tidal height, prey abundance, predator abundance and ray behavior, we found that giant shovelnose rays and reticulate whiprays were most often found resting in nearshore microhabitats, especially at low tidal heights during the warm season. Microhabitat selection did not match predictions derived from distributions of prey. Although at a course scale, ray distributions appeared to match predictions of behavioral thermoregulation theory, fine-scale examination revealed a mismatch. The selection of the shallow nearshore microhabitat at low tidal heights during periods of high predator abundance (warm season suggests that this microhabitat may serve as a refuge, although it may come with metabolic costs due to higher temperatures. The results of this study highlight the importance of predators in the habitat selection decisions of mesoconsumers and that within thermal gradients, factors, such as predation risk, must be considered in addition to behavioral thermoregulation to explain habitat selection decisions. Furthermore, increasing water temperatures predicted by climate change may result in complex trade-offs that might have important implications for ecosystem dynamics.

  13. Microbial community diversity and composition varies with habitat characteristics and biofilm function in macrophyte-rich streams

    DEFF Research Database (Denmark)

    Levi, Peter S.; Starnawski, Piotr; Poulsen, Britta

    2017-01-01

    in these biofilms by creating microhabitats. Here we describe the prokaryotic and eukaryotic microbial diversity of biofilms in sand and macrophyte habitats (i.e. epipsammon and epiphyton, respectively) in five macrophyte-rich streams in Jutland, Denmark. The macrophyte species varied in growth morphology, C...... as determined by measuring the similarity among communities (i.e. Sørensen similarity index). Furthermore, we found significant correlations between microbial diversity (i.e. Chao1 rarefied richness and Pielou’s evenness) and biofilm structure and function (i.e. C:N ratio and ammonium uptake efficiency...... dominated by Stramenopiles (i.e. diatoms). For both the prokaryotes and eukaryotes, the epipsammon were consistently the most diverse communities and the epiphytic communities were generally similar among the four macrophyte species. However, the communities on the least complex macrophyte, Sparganium...

  14. Lethal thermal maxima for age-0 pallid and shovelnose sturgeon: Implications for shallow water habitat restoration

    Science.gov (United States)

    Deslauriers, David; Heironimus, Laura B.; Chipps, Steven R.

    2016-01-01

    We evaluated temperature tolerance in age-0 pallid and shovelnose sturgeon (Scaphirhynchus albus and Scaphirhynchus platorynchus), two species that occur sympatrically in the Missouri and Mississippi Rivers. Fish (0.04–18 g) were acclimated to water temperatures of 13, 18 or 24 °C to quantify temperatures associated with lethal thermal maxima (LTM). The results show that no difference in thermal tolerance existed between the two sturgeon species, but that LTM was significantly related to body mass and acclimation temperature. Multiple linear regression analysis was used to estimate LTM, and outputs from the model were compared with water temperatures measured in the shallow water habitat (SWH) of the Missouri River. Observed SWH temperatures were not found to yield LTM conditions. The model developed here is to serve as a general guideline in the development of future SWH.

  15. Estimating thermal regimes of bull trout and assessing the potential effects of climate warming on critical habitats

    Science.gov (United States)

    Jones, Leslie A.; Muhlfeld, Clint C.; Marshall, Lucy A.; McGlynn, Brian L.; Kershner, Jeffrey L.

    2013-01-01

    Understanding the vulnerability of aquatic species and habitats under climate change is critical for conservation and management of freshwater systems. Climate warming is predicted to increase water temperatures in freshwater ecosystems worldwide, yet few studies have developed spatially explicit modelling tools for understanding the potential impacts. We parameterized a nonspatial model, a spatial flow-routed model, and a spatial hierarchical model to predict August stream temperatures (22-m resolution) throughout the Flathead River Basin, USA and Canada. Model comparisons showed that the spatial models performed significantly better than the nonspatial model, explaining the spatial autocorrelation found between sites. The spatial hierarchical model explained 82% of the variation in summer mean (August) stream temperatures and was used to estimate thermal regimes for threatened bull trout (Salvelinus confluentus) habitats, one of the most thermally sensitive coldwater species in western North America. The model estimated summer thermal regimes of spawning and rearing habitats at <13 C° and foraging, migrating, and overwintering habitats at <14 C°. To illustrate the useful application of such a model, we simulated climate warming scenarios to quantify potential loss of critical habitats under forecasted climatic conditions. As air and water temperatures continue to increase, our model simulations show that lower portions of the Flathead River Basin drainage (foraging, migrating, and overwintering habitat) may become thermally unsuitable and headwater streams (spawning and rearing) may become isolated because of increasing thermal fragmentation during summer. Model results can be used to focus conservation and management efforts on populations of concern, by identifying critical habitats and assessing thermal changes at a local scale.

  16. Molecular analysis of the benthos microbial community in Zavarzin thermal spring (Uzon Caldera, Kamchatka, Russia).

    Science.gov (United States)

    Rozanov, Alexey S; Bryanskaya, Alla V; Malup, Tatiana K; Meshcheryakova, Irina A; Lazareva, Elena V; Taran, Oksana P; Ivanisenko, Timofey V; Ivanisenko, Vladimir A; Zhmodik, Sergey M; Kolchanov, Nikolay A; Peltek, Sergey E

    2014-01-01

    Geothermal areas are of great interest for the study of microbial communities. The results of such investigations can be used in a variety of fields (ecology, microbiology, medicine) to answer fundamental questions, as well as those with practical benefits. Uzon caldera is located in the Uzon-Geyser depression that is situated in the centre of the Karym-Semyachin region of the East Kamchatka graben-synclinorium. The microbial communities of Zavarzin spring are well studied; however, its benthic microbial mat has not been previously described. Pyrosequencing of the V3 region of the 16S rRNA gene was used to study the benthic microbial community of the Zavarzin thermal spring (Uzon Caldera, Kamchatka). The community is dominated by bacteria (>95% of all sequences), including thermophilic, chemoorganotrophic Caldiserica (33.0%) and Dictyoglomi (24.8%). The benthic community and the previously examined planktonic community of Zavarzin spring have qualitatively similar, but quantitatively different, compositions. In this study, we performed a metagenomic analysis of the benthic microbial mat of Zavarzin spring. We compared this benthic community to microbial communities found in the water and of an integral probe consisting of water and bottom sediments. Various phylogenetic groups of microorganisms, including potentially new ones, represent the full-fledged trophic system of Zavarzin. A thorough geochemical study of the spring was performed.

  17. Lava Flow Alteration at Craters of the Moon, Idaho, as an Analog for Microbial Habitat on Mars

    Science.gov (United States)

    Kobs-Nawotniak, S. E.; Hughes, S. S.; Elphic, R. C.; Sehlke, A.; Haberle, C. W.; Brady, A. L.; Payler, S.; Cockell, C. S.; Lim, D. S. S.

    2016-12-01

    Craters of the Moon National Monument and Preserve (COTM), Idaho is host to lava flows with comparable composition and texture to those observed on Mars. As part of the Biologic Analog Science Associated with Lava Terrains (BASALT) project, we investigated the relationship between alteration style and gradient scales in three young ( 2000 y.b.p.) lava flows at COTM. Alteration of volcanic substrate is known to improve microbial habitability. As such, our investigation seeks to identify and characterize microbial habitat analogs potentially representative of Noachian and Amazonian Mars. Alteration in these flows is dominantly the result of two processes; (1) syn-emplacement degassing and (2) sub-aerial interaction with eolian material and meteoric water. Syn-emplacement alteration products are dominated by hematite and goethite along with various clays and zeolites. These products are concentrated where heat persists during and following emplacement (e.g. proximal to eruptive and non-eruptive vents and in areas exhibiting significant textural transitions, possibly related to degassing concentrated along disrupted surfaces). The syn-eruptive alteration zones display mineralogical variation across cm-scales, and occur as patchy zones spanning multiple meters. Post-emplacement, ambient meteoric alteration is characterized by carbonates, zeolites and clays concentrated along fractures and within vesicles. Owing to their deposition along fractures, these alteration zones may be less than a millimeter thick, but span multiple meters. Our multidisciplinary team of geologists, microbiologists and organic geochemists seek to identify associations of alteration styles and microbial habitability.

  18. Thermal, mechanical and chemical control of ragweed (Ambrosia artemisiifolia in different habitats

    Directory of Open Access Journals (Sweden)

    Sölter, Ulrike

    2014-02-01

    Full Text Available A small plot field experiment with transplanted ragweed (Ambrosia artemisiifolia into gravel and grassland and a large scale field experiment on a roadside banquette in Brandenburg with a natural ragweed infestation were carried out. Thermal control treatments were hot air (gravel and grassland and hot water (roadside and flaming, the mechanical treatment was mowing and the chemical treatment was the application of the herbicide combination MCPA and Dicamba. The gravel and grassland experiment was conducted at two growth stages of ragweed (BBCH 16-18 and 22-29, at the roadside ragweed was at BBCH 50-65. Dry matter yield of ragweed was assessed 9 weeks after the treatments were conducted in gravel and grassland and 4 weeks after the treatment at the roadside. In gravel and grassland the best eradication at both growth stages by thermal control was achieved by hot air in comparison to the untreated plots (significant at P <0.05. And at the roadside significant lower dry matter was determined by hot water and flaming in comparison to the untreated plots (significant at P <0.05. The results of these experiments demonstrated the efficiency of thermal control methods based on hot air and hot water as an alternative to herbicide control and mowing in habitats where herbicide application is not allowed or mowing gives no sufficient eradication results, like on roadside banquettes.

  19. Thermal habitat constraints on zooplankton species associated with Atlantic cod (Gadus morhua) on the US Northeast Continental Shelf

    Science.gov (United States)

    Friedland, Kevin D.; Kane, Joe; Hare, Jonathan A.; Lough, R. Gregory; Fratantoni, Paula S.; Fogarty, Michael J.; Nye, Janet A.

    2013-09-01

    The US Northeast Continental Shelf is experiencing a period of increasing temperature levels and range, which impacts the quantity of thermal habitats within the ecosystem. With increasing temperatures, the amount of warmer, surface water thermal habitats (16-27 °C) has increased while there has been a reciprocal decline in cooler water habitats (5-15 °C). These cooler water habitats are the most abundant and comprise the core habitats of the ecosystem. The coldest thermal habitats (1-4 °C), however, have increased slightly in amount or have remained constant, reflecting a discontinuity in the progression of warming along a latitudinal gradient. This discontinuity may be the result of recent changes in the circulation of water masses in the northern Gulf of Maine, potentially associated with the Labrador Current. The contraction of core thermal habitats appears to have had biological consequences on multiple trophic levels. In particular, two zooplankton species associated with the larval feeding of Atlantic cod, Gadus morhua, have declined in abundance in the same areas where cod populations have exhibited continually poor recruitment. The zooplankton species group Pseudocalanus spp., which is associated with winter-spawning cod, has declined on Georges Bank and in the Eastern Gulf of Maine. The zooplankton Centropages typicus has declined in the Gulf of Maine during late summer into fall, potentially affecting spring-spawning cod in that area. These observations are consistent with the hypothesis that portions of the population complex of cod have lower reproductive output due to changes in zooplankton abundance, which we associate with the distribution of temperatures within the ecosystem.

  20. Microbial ecology of extreme environments: Antarctic dry valley yeasts and growth in substrate limited habitats

    Science.gov (United States)

    Vishniac, H. S.

    1981-01-01

    The multiple stresses temperature, moisture, and for chemoheterotrophs, sources of carbon and energy of the Dry Valley Antarctica soils allow at best depauperate communities, low in species diversity and population density. The nature of community structure, the operation of biogeochemical cycles, the evolution and mechanisms of adaptation to this habitat are of interest in informing speculations upon life on other planets as well as in modeling the limits of gene life. Yeasts of the Cryptococcus vishniacil complex (Basidiobiastomycetes) are investigated, as the only known indigenes of the most hostile, lichen free, parts of the Dry Valleys. Methods were developed for isolating these yeasts (methods which do not exclude the recovery of other microbiota). The definition of the complex was refined and the importance of nitrogen sources was established as well as substrate competition in fitness to the Dry Valley habitats.

  1. Response of core microbial consortia to hydrocarbon contaminations in coastal sediment habitats

    Directory of Open Access Journals (Sweden)

    Mathilde Jeanbille

    2016-10-01

    Full Text Available Traditionally, microbial surveys investigating the effect of chronic anthropogenic pressure such as polyaromatic hydrocarbons (PAHs contaminations consider just the alpha and beta diversity and ignore the interactions among the different taxa forming the microbial community. Here, we investigated the ecological relationships between the three domains of life (i.e. Bacteria, Archaea and Eukarya using 454 pyrosequencing data of the 16S rRNA and 18S rRNA genes from chronically impacted and pristine sediments, along the coasts of the Mediterranean Sea (Gulf of Lion, Vermillion coast, Corsica, Bizerte lagoon and Lebanon and the French Atlantic Ocean (Bay of Biscay and English Channel. Our approach provided a robust ecological framework for the partition of the taxa abundance distribution into 859 core OTUs and 6629 satellite OTUs. OTUs forming the core microbial community showed the highest sensitivity to changes in environmental and contaminant variations, with salinity, latitude, temperature, particle size distribution, total organic carbon (TOC and PAH concentrations as main drivers of community assembly. The core communities were dominated by Gammaproteobacteria and Deltaproteobacteria for Bacteria, by Thaumarchaeota, Bathyarchaeota and Thermoplasmata for Archaea and Metazoa and Dinoflagellata for Eukarya. In order to find associations among microorganisms, we generated a co-occurrence network in which PAHs were found to impact significantly the potential predator – prey relationship in one microbial consortium composed of ciliates and Actinobacteria. Comparison of network topological properties between contaminated and non-contaminated samples showed substantial differences in the structure of the network and indicated a higher vulnerability to environmental perturbations in the contaminated sediments.

  2. Aquatic microbial habitats within a neotropical rainforest: bromeliads and pH-associated trends in bacterial diversity and composition.

    Science.gov (United States)

    Goffredi, Shana K; Kantor, Adam H; Woodside, Walter T

    2011-04-01

    Tank-forming bromeliads, suspended in the rainforest canopy, possess foliage arranged in compact rosettes capable of long-term retention of rainwater. This large and unique aquatic habitat is inhabited by microorganisms involved in the important decomposition of impounded material. Moreover, these communities are likely influenced by environmental factors such as pH, oxygen, and light. Bacterial community composition and diversity was determined for the tanks of several bromeliad species (Aechmea and Werauhia) from northern Costa Rica, which span a range of parameters, including tank morphology and pH. These were compared with a nearby forest soil sample, an artificial tank (amber bottle), and a commercially available species (Aechmea). Bacterial community diversity, as measured by 16S rRNA analysis and tRFLP, showed a significant positive correlation with tank pH. A majority of 16S rRNA bacterial phylotypes found in association with acidic bromeliad tanks of pH  5.3, including the commercial bromeliad with the highest pH (6.7), were dominated by Betaproteobacteria, Firmicutes, and Bacteroidetes. To empirically determine the effect of pH on bacterial community, the tank pH of a specimen of Aechmea was depressed, in the field, from 6.5 to 4.5, for 62 days. The resulting community changed predictably with decreased abundance of Betaproteobacteria and Firmicutes and a concomitant increase in Alphaproteobacteria and Acidobacteria. Collectively, these results suggest that bromeliad tanks provide important habitats for a diverse microbial community, distinct from the surrounding environment, which are influenced greatly by acid-base conditions. Additionally, total organic carbon (∼46%) and nitrogen (∼2%) of bromeliad-impounded sediment was elevated relative to soil and gene surveys confirmed the presence of both chitinases and nitrogenases, suggesting that bromeliad tanks may provide important habitats for microbes involved in the biological cycling of carbon and

  3. Effect of Microwave Treatment on Microbial Contamination of Honeys and on Their Physicochemical and Thermal Properties

    Directory of Open Access Journals (Sweden)

    Paz Moliné María de la

    2015-06-01

    Full Text Available In recent years, microwave heating has become a common method for pasteurization and sterilization of food. Honey is a sweet substance produced by worker honeybees from nectar of flowers. The major microbial contaminants include moulds and yeasts, as well as the spore-forming bacteria, being their counts indicative of honeys’ commercial quality and safety. Paenibacillus larvae is also of interest since it causes American foulbrood (AFB in honeybee larvae. The main quality factors that are used in the honey international trade are moisture, hydroxymethylfurfural content (HMF, and enzymatic indices. Moreover, honey exhibits several thermal events, the most important being the glass transition temperature (Tg. The aim of this work was to evaluate microwave effect (800 watts during 45 and 90 seconds on microbial content in particular over P. larvae spores retained in honey, and on physicochemical and thermal properties. Microwave promoted a decrease of microbial count with time of exposure, including P. larvae. Moisture content diminished after treatment, while Tg increased linearly, and acidity decremented in the majority of cases. Honeys darkened and HMF exceeded the permissible value. Diastase and glucose-oxidase enzymes were totally inactivated by microwave treatment.

  4. Microbial community analysis of pH 4 thermal springs in Yellowstone National Park.

    Science.gov (United States)

    Jiang, Xiaoben; Takacs-Vesbach, Cristina D

    2017-01-01

    The pH of the majority of thermal springs in Yellowstone National Park (YNP) is from 1 to 3 and 6 to 10; relatively few springs (~5%) have a pH range of 4-5. We used 16S rRNA gene pyrosequencing to investigate microbial communities sampled from four pH 4 thermal springs collected from four regions of YNP that differed in their fluid temperature and geochemistry. Our results revealed that the composition of bacterial communities varied among the sites, despite sharing similar pH values. The taxonomic composition and metabolic functional potential of the site with the lowest temperature (55 °C), a thermal spring from the Seven Mile Hole (SMH) area, were further investigated using shotgun metagenome sequencing. The taxonomic classification, based on 372 Mbp of unassembled metagenomic reads, indicated that this community included a high proportion of Chloroflexi, Bacteroidetes, Proteobacteria, and Firmicutes. Functional comparison with other YNP thermal spring metagenomes indicated that the SMH metagenome was enriched in genes related to energy production and conversion, transcription, and carbohydrate transport. Analysis of genes involved in nitrogen metabolism revealed assimilatory and dissimilatory nitrate reduction pathways, whereas the majority of genes involved in sulfur metabolism were related to the reduction of sulfate to adenylylsulfate, sulfite, and H2S. Given that pH 4 thermal springs are relatively less common in YNP and thermal areas worldwide, they may harbor novel microbiota and the communities that inhabit them deserve further investigation.

  5. Microbial community composition and endolith colonization at an Arctic thermal spring are driven by calcite precipitation

    Science.gov (United States)

    Starke, Verena; Kirshtein, Julie; Fogel, Marilyn L.; Steele, Andrew

    2013-01-01

    Environmental conditions shape community composition. Arctic thermal springs provide an opportunity to study how environmental gradients can impose strong selective pressures on microbial communities and provide a continuum of niche opportunities. We use microscopic and molecular methods to conduct a survey of microbial community composition at Troll Springs on Svalbard, Norway, in the high Arctic. Microorganisms there exist under a wide range of environmental conditions: in warm water as periphyton, in moist granular materials, and in cold, dry rock as endoliths. Troll Springs has two distinct ecosystems, aquatic and terrestrial, together in close proximity, with different underlying environmental factors shaping each microbial community. Periphyton are entrapped during precipitation of calcium carbonate from the spring's waters, providing microbial populations that serve as precursors for the development of endolithic communities. This process differs from most endolith colonization, in which the rock predates the communities that colonize it. Community composition is modulated as environmental conditions change within the springs. At Troll, the aquatic environments show a small number of dominant operational taxonomic units (OTUs) that are specific to each sample. The terrestrial environments show a more even distribution of OTUs common to multiple samples.

  6. Spatial variability of microbial assemblages associated with a dominant habitat-forming seaweed

    Directory of Open Access Journals (Sweden)

    Alexandra Helene Campbell

    2015-03-01

    Full Text Available Macroalgal surfaces support abundant and diverse microorganisms within biofilms, which are often involved in fundamental functions relating to the health and defence of their seaweed hosts, including algal development, facilitation of spore release and chemical antifouling. Given these intimate and important interactions, environmental changes have the potential to negatively impact macroalgae by disrupting seaweed-microbe interactions. We used the disappearance of the dominant canopy-forming fucoid Phyllospora comosa from the metropolitan coast of Sydney, Australia as a model system to study these interactions. We transplanted Phyllospora individuals from nearby, extant populations back onto reefs in Sydney to test whether bacterial assemblages associated with seaweed surfaces would be influenced by (i the host itself, independently of where it occurs, (ii the type of habitat where the host occurs or (iii site-specific differences. Analyses of bacterial DNA fingerprints (TRFLPs indicated that assemblages of bacteria on Phyllospora were not habitat-specific. Rather, they were primarily influenced by local, site-specific conditions with some evidence for host-specificity in some cases. This could suggest a lottery model of host-surface colonisation, by which hosts are colonised by ‘suitable’ bacteria available in the local species pool, resulting in high variability in assemblage structure across sites, but where some species in the community are specific to the host and possibly influenced by differences in host traits.

  7. Geomicrobiology of sublacustrine thermal vents in Yellowstone Lake: Geochemical controls on microbial community structure and function

    Directory of Open Access Journals (Sweden)

    William P. Inskeep

    2015-10-01

    Full Text Available Yellowstone Lake (Yellowstone National Park, WY, USA is a large high-altitude (2200 m, fresh-water lake, which straddles an extensive caldera and is the center of significant geothermal activity. The primary goal of this interdisciplinary study was to evaluate the microbial populations inhabiting thermal vent communities in Yellowstone Lake (Yellowstone Lake using 16S rRNA gene and random metagenome sequencing, and to determine how geochemical attributes of vent waters influence the distribution of specific microorganisms and their metabolic potential. Thermal vent waters and associated microbial biomass were sampled during two field seasons (2007 - 2008 using a remotely operated vehicle (ROV. Sublacustrine thermal vent waters (circa 50 - 90 oC contained elevated concentrations of numerous constituents associated with geothermal activity including dissolved hydrogen, sulfide, methane and carbon dioxide. Microorganisms associated with sulfur-rich filamentous ‘streamer’ communities of Inflated Plain and West Thumb (pH range 5 - 6 were dominated by bacteria from the Aquificales, but also contained thermophilic archaea from the Crenarchaeota and Euryarchaeota. Novel groups of methanogens and members of the Korarchaeota were observed in vents from West Thumb and Elliot’s Crater (pH 5 - 6. Conversely, metagenome sequence from Mary Bay vent sediments did not yield large assemblies, and contained diverse thermophilic and nonthermophilic bacterial relatives. Analysis of functional genes associated with the major vent populations indicated a direct linkage to high concentrations of carbon dioxide, reduced sulfur (sulfide and/or elemental S, hydrogen and methane in the deep thermal ecosystems. Our observations show that sublacustrine thermal vents in Yellowstone Lake support novel thermophilic communities, which contain microorganisms with functional attributes not found to date in terrestrial geothermal systems of YNP.

  8. Microbial ecology of extreme environments: Antarctic dry valley yeasts and growth in substrate-limited habitats

    Science.gov (United States)

    Vishniac, H. S.

    1982-01-01

    The success of the Antarctic Dry Valley yeasts presumeably results from adaptations to multiple stresses, to low temperatures and substrate-limitation as well as prolonged resting periods enforced by low water availability. Previous investigations have suggested that the crucial stress is substrate limitation. Specific adaptations may be pinpointed by comparing the physiology of the Cryptococcus vishniacii complex, the yeasts of the Tyrol Valley, with their congeners from other habitats. Progress was made in methods of isolation and definition of ecological niches, in the design of experiments in competition for limited substrate, and in establishing the relationships of the Cryptococcus vishniacii complex with other yeasts. In the course of investigating relationships, a new method for 25SrRNA homology was developed. For the first time it appears that 25SrRNA homology may reflect parallel or convergent evolution.

  9. A Mediterranean free-floating peat mire hosts microbial communities shared by cold latitude habitats

    Science.gov (United States)

    Concheri, Giuseppe; Stevanato, Piergiorgio; Zaccone, Claudio; Shotyk, William; D'Orazio, Valeria; Miano, Teodoro; Lobianco, Daniela; Piffanelli, Pietro; Rizzi, Valeria; Ferrandi, Chiara; Squartini, Andrea

    2017-04-01

    two main models. A remarkable feature is the coincidence of most taxa observed with database subjects isolated from mires and lakes in boreal/polar environments in spite of the fact that Posta Fibreno is located in sub-Mediterranean climate conditions. This instance suggests a common ecological feature linking peat-forming mires and habitats alike, in which the process factor would rule in determining the biotic composition in spite of the macroclimatic and geographical variables. The principle offers interpretive clues for a deeper understanding of a number of other biotic-environmental interplay contexts.

  10. Impacts of Discharge Reductions on Physical and Thermal Habitat Characteristics in a Desert Spring, Death Valley National Park, California, USA

    Science.gov (United States)

    Morrison, R. R.; Stone, M. C.; Sada, D. W.

    2013-12-01

    Desert springs are biodiversity hotspots that are sensitive to anthropogenic activities. Despite their importance, the effects of human disturbance on desert springs are not well known, and scarce information exists describing the biotic or environmental effects of incrementally increasing disturbance. The objective of this research was to quantify the influence of incremental reductions in discharge on the physical and thermal characteristics of a desert springbrook. This objective was accomplished through a combination of field experiments at Travertine Spring in Death Valley National Park, USA, and hydraulic/temperature modeling in order to: (1) quantify changes in physical characteristics of the springbrook channel and aquatic environment; (2) investigate the effects of reduced spring discharge on seasonal spatial temperature patterns; (3) delineate tipping points that exhibit a non-linear response to decreased flow. The study results supported our predictions that decreased discharge would modify physical habitat characteristics of the springbrook, reduce aquatic habitat volume, increase variability in water temperatures along the springbrook, and reduce springbrook suitability for invertebrates that require stable environments. Field observations revealed a significant relationship between water depth and flow velocity with reduced spring discharge. The rate of change of mean water depths, velocities, and habitat volumes were greatest with only a 10% reduction in spring flow. In addition, a non-linear temperature response to flow reductions was present under all modeled conditions. Generally, water temperature gradients increased as flows were decreased, and the sensitivity of reduced discharge increased with distance from the spring source. The degree of sensitivity was a function of season, which reflects the influence of ambient air temperature and wind in the cooling of the springbrook. These results suggest that habitat for species using stable thermal

  11. Microbial diversity in acidic thermal pools in the Uzon Caldera, Kamchatka.

    Science.gov (United States)

    Mardanov, Andrey V; Gumerov, Vadim M; Beletsky, Alexey V; Ravin, Nikolai V

    2017-08-16

    Microbial communities of four acidic thermal pools in the Uzon Caldera, Kamchatka, Russia, were studied using amplification and pyrosequencing of 16S rRNA gene fragments. The sites differed in temperature and pH: 1805 (60 °C, pH 3.7), 1810 (90 °C, pH 4.1), 1818 (80 °C, pH 3.5), and 1807 (86 °C, pH 5.6). Archaea of the order Sulfolobales were present among the dominant groups in all four pools. Acidilobales dominated in pool 1818 but were a minor fraction at the higher temperature in pool 1810. Uncultivated Archaea of the Hot Thaumarchaeota-related clade were present in significant quantities in pools 1805 and 1807, but they were not abundant in pools 1810 and 1818, where high temperatures were combined with low pH. Nanoarchaeota were present in all pools, but were more abundant in pools 1810 and 1818. A similar abundance pattern was observed for Halobacteriales. Thermophilic Bacteria were less diverse and were mostly represented by aerobic hydrogen- and sulfur-oxidizers of the phylum Aquificae and sulfur-oxidising Proteobacteria of the genus Acidithiobacillus. Thus we showed that extremely acidic hot pools contain diverse microbial communities comprising different metabolic groups of prokaryotes, including putative lithoautotrophs using energy sources of volcanic origin, and various facultative and obligate heterotrophs.

  12. Thermal pretreatment of the solid fraction of manure: Impact on the biogas reactor performance and microbial community

    DEFF Research Database (Denmark)

    Mladenovska, Z; Hartmann, H.; Kvist, T.

    2006-01-01

    and an improved removal of the volatile solids (VS). The properties of microbial communities of both reactors were analysed. The specific methanogenic activity (SMA) test showed that both biomasses had significant activity towards hydrogen and formate, while the activity with the VFA - acetate, propionate...... and butyrate - was low. The kinetic parameters of the VFA conversion revealed a reduced affinity of the microbial community from the CSTR fed with thermally pre-treated manure for acetate, propionate and butyrate. The bacterial and archaeal populations identified by t-RLFP analysis of 16S rRNA genes were found...

  13. Marine ecological habitat: A case study on projected thermal power plant around Dharamtar creek, India

    Digital Repository Service at National Institute of Oceanography (India)

    Kulkarni, V.A.; Naidu, V.S.; Jagtap, T.G.

    of intake and discharge of water for cooling. Discharges from such developments remain constant threat of increasing thermal pollution and affecting the quality of environment. The baseline information on prevailing quality of aquatic environment comes handy...

  14. Preliminary Analysis of Effects of Reduced Discharge onThermal Habitat of Pedersen Warm Springs Channel

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — A preliminary report to study the potential impacts of possible flow reductions in thermal spring systems located in the Warm Springs area of Moapa Valley NWR on the...

  15. Temperature Compensation of [U-14C]Glucose Incorporation by Microbial Communities in a River with a Fluctuating Thermal Regime

    OpenAIRE

    Witzel, Karl-Paul

    1980-01-01

    In summer, the river Saar in the southwest of Germany exhibits distinct temperature fluctuations from 8°C at the source to nearly 30°C in the middle region. Temperature optima for bacterial plate counts and the uptake velocity of [U-14C]glucose by the natural microbial communities of different regions ranged from 20 to 30°C, which is significantly above the mean annual water temperature. A correlation between temperature optima and different seasons or habitats was not observed. Despite the r...

  16. Modification of the submerged coil to prevent microbial carryover error in thermal death studies.

    Science.gov (United States)

    Keller, Susanne E; Shazer, Arlette G; Fleischman, Gregory J; Chirtel, Stuart; Anderson, Nathan; Larkin, John

    2008-04-01

    A submerged coil unit generates death rate data for foodborne pathogens through precise computer-controlled sequential sampling rather than the usual manually timed, labor-intensive single sampling associated with other approaches. Our work with Yersinia pseudotuberculosis and Listeria monocytogenes Scott A using the submerged coil unit indicated non-log-linear death rates with large degrees of tailing. Varying degrees of cell adhesion to the surface of the exit port resulted in carryover that was likely the primary cause of these non-log-linear kinetics. This carryover also resulted in erroneously high measured levels of thermal resistance for both organisms. To address the carryover problem, modifications were made to the exit port of the submerged coil unit to ensure continuous and uniform heat treatment. These modifications resulted in a 2-fold decrease in measured D-values for L. monocytogenes Scott A and a 10-fold decrease in measured D-values for Y. pseudotuberculosis. D-values measured with the modified machine for L. monocytogenes Scott A were similar to those found in the literature. Slight tailing in survival curves persisted with the modified method, particularly for Y. pseudotuberculosis. These results indicate that kinetic data for microbial death rates obtained using an unmodified submerged coil unit must be viewed with suspicion in light of the significant potential for carryover.

  17. Quality and microbial safety evaluation of new isotonic beverages upon thermal treatments.

    Science.gov (United States)

    Gironés-Vilaplana, Amadeo; Huertas, Juan-Pablo; Moreno, Diego A; Periago, Paula M; García-Viguera, Cristina

    2016-03-01

    In the present study, it was evaluated how two different thermal treatments (Mild and Severe) may affect the anthocyanin content, antioxidant capacity (ABTS(+), DPPH, and FRAP), quality (CIELAB colour parameters), and microbiological safety of a new isotonic drink made of lemon and maqui berry over a commercial storage simulation using a shelf life of 56days at two preservation temperature (7°C and 37°C). Both heat treatments did not affect drastically the anthocyanins content and their percentage of retention. The antioxidant capacity, probably because of the short time, was also not affected. The CIELAB colour parameters were affected by the heat, although the isotonic drinks remained with attractive red colour during shelf life. From a microbiological point of view, the Mild heat treatment with storage at 7°C is the ideal for the preservation of microbial growth, being useful for keeping the quality and safety of beverages in commercial life. Copyright © 2015. Published by Elsevier Ltd.

  18. Microbial Diversity and Biochemical Potential Encoded by Thermal Spring Metagenomes Derived from the Kamchatka Peninsula

    Directory of Open Access Journals (Sweden)

    Bernd Wemheuer

    2013-01-01

    Full Text Available Volcanic regions contain a variety of environments suitable for extremophiles. This study was focused on assessing and exploiting the prokaryotic diversity of two microbial communities derived from different Kamchatkian thermal springs by metagenomic approaches. Samples were taken from a thermoacidophilic spring near the Mutnovsky Volcano and from a thermophilic spring in the Uzon Caldera. Environmental DNA for metagenomic analysis was isolated from collected sediment samples by direct cell lysis. The prokaryotic community composition was examined by analysis of archaeal and bacterial 16S rRNA genes. A total number of 1235 16S rRNA gene sequences were obtained and used for taxonomic classification. Most abundant in the samples were members of Thaumarchaeota, Thermotogae, and Proteobacteria. The Mutnovsky hot spring was dominated by the Terrestrial Hot Spring Group, Kosmotoga, and Acidithiobacillus. The Uzon Caldera was dominated by uncultured members of the Miscellaneous Crenarchaeotic Group and Enterobacteriaceae. The remaining 16S rRNA gene sequences belonged to the Aquificae, Dictyoglomi, Euryarchaeota, Korarchaeota, Thermodesulfobacteria, Firmicutes, and some potential new phyla. In addition, the recovered DNA was used for generation of metagenomic libraries, which were subsequently mined for genes encoding lipolytic and proteolytic enzymes. Three novel genes conferring lipolytic and one gene conferring proteolytic activity were identified.

  19. Assessing Thermally Stressful Events in a Rhode Island Coldwater Fish Habitat Using the SWAT Model

    Directory of Open Access Journals (Sweden)

    Britta Chambers

    2017-09-01

    Full Text Available It has become increasingly important to recognize historical water quality trends so that the future impacts of climate change may be better understood. Climate studies have suggested that inland stream temperatures and average streamflow will increase over the next century in New England, thereby putting aquatic species sustained by coldwater habitats at risk. In this study we evaluated two different approaches for modeling historical streamflow and stream temperature in a Rhode Island, USA, watershed with the Soil and Water Assessment Tool (SWAT, using (i original SWAT and (ii SWAT plus a hydroclimatological model component that considers both hydrological inputs and air temperature. Based on daily calibration results with six years of measured streamflow and four years of stream temperature data, we examined occurrences of stressful conditions for brook trout (Salvelinus fontinalis using the hydroclimatological model. SWAT with the hydroclimatological component improved modestly during calibration (NSE of 0.93, R2 of 0.95 compared to the original SWAT (NSE of 0.83, R2 of 0.93. Between 1980–2009, the number of stressful events, a moment in time where high or low flows occur simultaneously with stream temperatures exceeding 21 °C, increased by 55% and average streamflow increased by 60%. This study supports using the hydroclimatological SWAT component and provides an example method for assessing stressful conditions in southern New England’s coldwater habitats.

  20. An unusual cyanobacterium from saline thermal waters with relatives from unexpected habitats.

    Science.gov (United States)

    Banerjee, Meenakshi; Everroad, R Craig; Castenholz, Richard W

    2009-07-01

    Cyanobacteria that grow above seawater salinity at temperatures above 45 degrees C have rarely been studied. Cyanobacteria of this type of thermo-halophilic extremophile were isolated from siliceous crusts at 40-45 degrees C in a geothermal seawater lagoon in southwest Iceland. Iceland Clone 2e, a Leptolyngbya morphotype, was selected for further study. This culture grew only at 45-50 degrees C, in medium ranging from 28 to 94 g L(-1) TDS, It showed 3 doublings 24 h(-1) under continuous illumination. This rate at 54 degrees C was somewhat reduced, and death occurred at 58 degrees C. A comparison of the 16S rDNA sequence with all others in the NCBI database revealed 2 related Leptolyngbya isolates from a Greenland hot spring (13-16 g L(-1) TDS). Three other similar sequences were from Leptolyngbya isolates from dry, endolithic habitats in Yellowstone National Park. All 6 formed a phylogenetic clade, suggesting common ancestry. These strains shared many similarities to Iceland Clone 2e with respect to temperature and salinity ranges and optima. Two endolithic Leptolyngbya isolates, grown previously at 23 degrees C in freshwater medium, grew well at 50 degrees C but only in saline medium. This study shows that limited genotypic similarity may reveal some salient phenotypic similarities, even when the related cyanobacteria are from vastly different and remote habitats.

  1. Habitat management affects soil chemistry and allochthonous organic inputs mediating microbial structure and exo-enzyme activity in Wadden Sea salt-marsh soils

    Science.gov (United States)

    Mueller, Peter; Granse, Dirk; Thi Do, Hai; Weingartner, Magdalena; Nolte, Stefanie; Hoth, Stefan; Jensen, Kai

    2016-04-01

    The Wadden Sea (WS) region is Europe's largest wetland and home to approximately 20% of its salt marsh area. Mainland salt marshes of the WS are anthropogenically influenced systems and have traditionally been used for livestock grazing in wide parts. After foundation of WS National Parks in the late 1980s and early 1990s, artificial drainage has been abandoned; however, livestock grazing is still common in many areas of the National Parks and is under ongoing discussion as a habitat-management practice. While studies so far focused on effects of livestock grazing on biodiversity, little is known about how biogeochemical processes, element cycling, and particularly carbon sequestration are affected. Here, we present data from a recent field study focusing on grazing effects on soil properties, microbial exo-enzyme activity, microbial abundance and structure. Exo-enzyme activity was studied conducting digestive enzyme assays for various enzymes involved in C- and N cycling. Microbial abundance and structure was assessed measuring specific gene abundance of fungi and bacteria using quantitative PCR. Soil compaction induced by grazing led to higher bulk density and decreases in soil redox (Δ >100 mV). Soil pH was significantly lower in grazed parts. Further, the proportion of allochthonous organic matter (marine input) was significantly smaller in grazed vs. ungrazed sites, likely caused by a higher sediment trapping capacity of the taller vegetation in the ungrazed sites. Grazing induced changes in bulk density, pH and redox resulted in reduced activity of enzymes involved in microbial C acquisition; however, there was no grazing effect on enzymes involved in N acquisition. While changes in pH, bulk density or redox did not affect microbial abundance and structure, the relative amount of marine organic matter significantly reduced the relative abundance of fungi (F:B ratio). We conclude that livestock grazing directly affects microbial exo-enzyme activity, thus

  2. In situ dynamics of O2, pH, light and photosynthesis in ikaite tufa columns (Ikka Fjord, Greenland – a unique microbial habitat.

    Directory of Open Access Journals (Sweden)

    Erik Christian Løvbjerg Trampe

    2016-05-01

    Full Text Available The Ikka Fjord (SW Greenland harbors a unique microbial habitat in the form of several hundred submarine tufa columns composed of ikaite, a special hexahydrate form of calcium carbonate that precipitates when alkaline phosphate- and carbonate-enriched spring water seeping out of the sea floor meets cold seawater. While several unique heterotrophic microbes have been isolated from the tufa columns, the microbial activity and the boundary conditions for microbial growth in ikaite have remained unexplored. We present the first detailed in situ characterization of the physico-chemical microenvironment and activity of oxygenic phototrophs thriving within the ikaite columns. In situ underwater microsensor measurements of pH, temperature, and irradiance in the porous ikaite crystal matrix, revealed an extreme microenvironment characterized by low temperatures, strong light attenuation, and gradients of pH changing from pH 9 at the outer column surface to above pH 10 over the first 1-2 cm of the ikaite. This outer layer of the freshly deposited ikaite matrix contained densely pigmented yellow and green zones harboring a diverse phototrophic community dominated by diatoms and cyanobacteria, respectively, as shown by amplicon sequencing. In situ O2 measurements, as well as underwater variable chlorophyll fluorescence measurements of photosynthetic activity, demonstrated high levels of oxygenic photosynthesis in this extreme gradient environment with strong irradiance-driven O2 dynamics ranging from anoxia to hyperoxic conditions in the ikaite matrix, albeit the local formation of gas bubbles buffered the day-night dynamics of O2 in the tufa columns. The microbial phototrophs in the ikaite matrix are embedded in exopolymers forming endolithic biofilms that may interact with mineral formation and cementing of ikaite crystals.

  3. Impact-shocked rocks--insights into Archean and extraterrestrial microbial habitats (and sites for prebiotic chemistry?)

    Science.gov (United States)

    Cockell, C. S.

    2004-01-01

    Impact-shocked gneiss shocked to greater than 10 GPa in the Haughton impact structure in the Canadian High Arctic has an approximately 25-times greater pore surface area than unshocked rocks. These pore spaces provide microhabitats for a diversity of heterotrophic microorganisms and in the near-surface environment of the rocks, where light levels are sufficient, cyanobacteria. Shocked rocks provide a moisture retaining, UV protected microenvironment. During the Archean, when impact fluxes were more than two orders of magnitude higher than today, the shocked-rock habitat was one of the most common terrestrial habitats and might have provided a UV-shielded refugium for primitive life. These potential habitats are in high abundance on Mars where impact crater habitats could have existed over geologic time periods of billions of years, suggesting that impact-shocked rocks are important sites to search for biomolecules in extraterrestrial life detection strategies. In addition to being favourable sites for life, during the prebiotic period of planetary history impact-shocked rocks might have acted as a site for the concentration of reactants for prebiotic syntheses. c2004 COSPAR. Published by Elsevier Ltd. All rights reserved.

  4. Temperature compensation of [u-C]glucose incorporation by microbial communities in a river with a fluctuating thermal regime.

    Science.gov (United States)

    Witzel, K P

    1980-04-01

    In summer, the river Saar in the southwest of Germany exhibits distinct temperature fluctuations from 8 degrees C at the source to nearly 30 degrees C in the middle region. Temperature optima for bacterial plate counts and the uptake velocity of [U-C]glucose by the natural microbial communities of different regions ranged from 20 to 30 degrees C, which is significantly above the mean annual water temperature. A correlation between temperature optima and different seasons or habitats was not observed. Despite the relatively high temperature optima, the turnover time for glucose was shortest at temperatures around the mean annual water temperature, due to changes in the substrate affinity. At limiting substrate concentrations, the higher substrate affinity at lower temperatures may lead to a higher real activity at in situ temperatures, and a compensatory stabilization of uptake rates at fluctuating temperatures is possible.

  5. Predicting future thermal habitat suitability of competing native and invasive fish species: from metabolic scope to oceanographic modelling.

    Science.gov (United States)

    Marras, Stefano; Cucco, Andrea; Antognarelli, Fabio; Azzurro, Ernesto; Milazzo, Marco; Bariche, Michel; Butenschön, Momme; Kay, Susan; Di Bitetto, Massimiliano; Quattrocchi, Giovanni; Sinerchia, Matteo; Domenici, Paolo

    2015-01-01

    Global increase in sea temperatures has been suggested to facilitate the incoming and spread of tropical invaders. The increasing success of these species may be related to their higher physiological performance compared with indigenous ones. Here, we determined the effect of temperature on the aerobic metabolic scope (MS) of two herbivorous fish species that occupy a similar ecological niche in the Mediterranean Sea: the native salema (Sarpa salpa) and the invasive marbled spinefoot (Siganus rivulatus). Our results demonstrate a large difference in the optimal temperature for aerobic scope between the salema (21.8°C) and the marbled spinefoot (29.1°C), highlighting the importance of temperature in determining the energy availability and, potentially, the distribution patterns of the two species. A modelling approach based on a present-day projection and a future scenario for oceanographic conditions was used to make predictions about the thermal habitat suitability (THS, an index based on the relationship between MS and temperature) of the two species, both at the basin level (the whole Mediterranean Sea) and at the regional level (the Sicilian Channel, a key area for the inflow of invasive species from the Eastern to the Western Mediterranean Sea). For the present-day projection, our basin-scale model shows higher THS of the marbled spinefoot than the salema in the Eastern compared with the Western Mediterranean Sea. However, by 2050, the THS of the marbled spinefoot is predicted to increase throughout the whole Mediterranean Sea, causing its westward expansion. Nevertheless, the regional-scale model suggests that the future thermal conditions of Western Sicily will remain relatively unsuitable for the invasive species and could act as a barrier for its spread westward. We suggest that metabolic scope can be used as a tool to evaluate the potential invasiveness of alien species and the resilience to global warming of native species.

  6. Following the kinetics: iron-oxidizing microbial mats in cold icelandic volcanic habitats and their rock-associated carbonaceous signature.

    Science.gov (United States)

    Cockell, Charles S; Kelly, Laura C; Summers, Stephen; Marteinsson, Viggo

    2011-09-01

    Icelandic streams with mean annual temperatures of less than 5 °C, which receive the cationic products of basaltic rock weathering, were found to host mats of iron-cycling microorganisms. We investigated two representative sites. Iron-oxidizing Gallionella and iron-reducing Geobacter species were present. The mats host a high bacterial diversity as determined by culture-independent methods. β-Proteobacteria, Actinobacteria, α-Proteobacteria, and Bacteroidetes were abundant microbial taxa. The mat contained a high number of phototroph sequences. The carbon compounds in the mat displayed broad G and D bands with Raman spectroscopy. This signature becomes incorporated into the weathered oxidized surface layer of the basaltic rocks and was observed on rocks that no longer host mats. The presence of iron-oxidizing taxa in the stream microbial mats, and the lack of them in previously studied volcanic rocks in Iceland that have intermittently been exposed to surface water flows, can be explained by the kinetic limitations to the extraction of reduced iron from rocks. This type of ecosystem illustrates key factors that control the distribution of chemolithotrophs in cold volcanic environments. The data show that one promising sample type for which the hypothesis of the existence of past life on Mars can be tested is the surface of volcanic rocks that, previously, were situated within channels carved by flowing water. Our results also show that the carbonaceous signatures of life, if life had occurred, could be found in or on these rocks.

  7. High-resolution in-situ thermal imaging of microbial mats at El Tatio Geyser, Chile shows coupling between community color and temperature

    Science.gov (United States)

    Dunckel, Anne E.; Cardenas, M. Bayani; Sawyer, Audrey H.; Bennett, Philip C.

    2009-12-01

    Microbial mats have spatially heterogeneous structured communities that manifest visually through vibrant color zonation often associated with environmental gradients. We report the first use of high-resolution thermal infrared imaging to map temperature at four hot springs within the El Tatio Geyser Field, Chile. Thermal images with millimeter resolution show drastic variability and pronounced patterning in temperature, with changes on the order of 30°C within a square decimeter. Paired temperature and visual images show that zones with specific coloration occur within distinct temperature ranges. Unlike previous studies where maximum, minimum, and optimal temperatures for microorganisms are based on isothermally-controlled laboratory cultures, thermal imaging allows for mapping thousands of temperature values in a natural setting. This allows for efficiently constraining natural temperature bounds for visually distinct mat zones. This approach expands current understanding of thermophilic microbial communities and opens doors for detailed analysis of biophysical controls on microbial ecology.

  8. Interplay of robustness and plasticity of life-history traits drives ecotypic differentiation in thermally distinct habitats.

    Science.gov (United States)

    Liefting, M; van Grunsven, R H A; Morrissey, M B; Timmermans, M J T N; Ellers, J

    2015-05-01

    Phenotypic plasticity describes the ability of an individual to alter its phenotype in response to the environment and is potentially adaptive when dealing with environmental variation. However, robustness in the face of a changing environment may often be beneficial for traits that are tightly linked to fitness. We hypothesized that robustness of some traits may depend on specific patterns of plasticity within and among other traits. We used a reaction norm approach to study robustness and phenotypic plasticity of three life-history traits of the collembolan Orchesella cincta in environments with different thermal regimes. We measured adult mass, age at maturity and growth rate of males and females from heath and forest habitats at two temperatures (12 and 22 °C). We found evidence for ecotype-specific robustness of female adult mass to temperature, with a higher level of robustness in the heath ecotype. This robustness is facilitated by plastic adjustments of growth rate and age at maturity. Furthermore, female fecundity is strongly influenced by female adult mass, explaining the importance of realizing a high mass across temperatures for females. These findings indicate that different predicted outcomes of life-history theory can be combined within one species' ontogeny and that models describing life-history strategies should not assume that traits like growth rate are maximized under all conditions. On a methodological note, we report a systematic inflation of variation when standard deviations and correlation coefficients are calculated from family means as opposed to individual data within a family structure. © 2015 European Society For Evolutionary Biology. Journal of Evolutionary Biology © 2015 European Society For Evolutionary Biology.

  9. Effects of climate change and wildfire on stream temperatures and salmonid thermal habitat in a mountain river network

    Science.gov (United States)

    Daniel J. Isaak; Charles H. Luce; Bruce E. Rieman; David E. Nagel; Erin E. Peterson; Dona L. Horan; Sharon Parkes; Gwynne L. Chandler

    2010-01-01

    Mountain streams provide important habitats for many species, but their faunas are especially vulnerable to climate change because of ectothermic physiologies and movements that are constrained to linear networks that are easily fragmented. Effectively conserving biodiversity in these systems requires accurate downscaling of climatic trends to local habitat conditions...

  10. Microbial life in Bourlyashchy, the hottest thermal pool of Uzon Caldera, Kamchatka.

    Science.gov (United States)

    Chernyh, Nikolay A; Mardanov, Andrey V; Gumerov, Vadim M; Miroshnichenko, Margarita L; Lebedinsky, Alexander V; Merkel, Alexander Y; Crowe, Douglas; Pimenov, Nikolay V; Rusanov, Igor I; Ravin, Nikolay V; Moran, Mary Ann; Bonch-Osmolovskaya, Elizaveta A

    2015-11-01

    Bourlyashchy is the largest and hottest pool in the Uzon Caldera, located in the territory of Kronotsky Nature Reserve, Kamchatka, Russia, with sediment surface temperatures at the margins ranging from 86 to 97 °C, and pH from 6.0 to 7.0. The microbial communities of the pool water and sediments were studied comprehensively from 2005 to 2014. Radioisotopic tracer studies revealed the processes of inorganic carbon assimilation, sulfate reduction, lithotrophic methanogenesis and potentially very active process of acetate oxidation to CO2. The total number of microbial cells in water was different in different years ranging from 5.2 to 7.0 × 10(6); in sediments, it changed from year to year between 6.3 × 10(6) and 1.75 × 10(8), increasing with a decrease in temperature. FISH with Archaea- and Bacteria-specific probes showed that the share of Bacteria differed with year, changing from 34 to 71%. According to 16S rRNA gene pyrosequencing data, lithoautotrophs (Aquificales and Thermoproteales) predominated in water samples, while in sediments they shared the niche with organotrophic Crenarchaeota, Korarchaeota, and bacteria of the genus Caldimicrobium (phylum Thermodesulfobacteria). The majority of organisms in water belonged to cultivated orders of prokaryotes; the only large uncultured group was that representing a novel order in class Thermoprotei. In sediments, unclassified Aquificeae comprised a significant part of the bacterial population. Thus, we showed that the hottest of the terrestrial hot pools studied contains numerous and active microbial populations where Bacteria represent a significant part of the microbial community, and planktonic and sediment populations differ in both composition and function.

  11. 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.

  12. The microbial temperature sensitivity to warming is controlled by thermal adaptation and is independent of C-quality across a pan-continental survey

    Science.gov (United States)

    Berglund, Eva; Rousk, Johannes

    2017-04-01

    Climate models predict that warming will result in an increased loss of soil organic matter (SOM). However, field experiments suggest that although warming results in an immediate increase in SOM turnover, the effect diminishes over time. Although the use and subsequent turnover of SOM is dominated by the soil microbial community, the underlying physiology underpinning warming responses are not considered in current climate models. It has been suggested that a reduction in the perceived quality of SOM to the microbial community, and changes in the microbial thermal adaptation, could be important feed-backs to soil warming. Thus, studies distinguishing between temperature relationships and how substrate quality influences microbial decomposition are a priority. We examined microbial communities and temperature sensitivities along a natural climate gradient including 56 independent samples from across Europe. The gradient included mean annual temperatures (MAT) from ca -4 to 18 ˚ C, along with wide spans of environmental factors known to influence microbial communities, such as pH (4.0 to 8.8), nutrients (C/N from 7 to 50), SOM (from 4 to 94%), and plant communities, etc. The extensive ranges of environmental conditions resulted in wide ranges of substrate quality, indexed as microbial respiration per unit SOM, from 5-150 μg CO2g-1 SOM g-1 h-1. We hypothesised microbial communities to (1) be adapted to the temperature of their climate, leading to warm adapted bacterial communities that were more temperature sensitive (higher Q10s) at higher MAT; (2) have temperature sensitivities affected by the quality of SOM, with higher Q10s for lower quality SOM. To determine the microbial use of SOM and its dependence on temperature, we characterized microbial temperature dependences of bacterial growth (leu inc), fungal growth (ac-in-erg) and soil respiration in all 56 sites. Temperature dependences were determined using brief (ca. 1-2 h at 25˚ C) laboratory incubation

  13. Microbial dinitrogen fixation in coral holobionts exposed to thermal stress and bleaching.

    Science.gov (United States)

    Cardini, Ulisse; van Hoytema, Nanne; Bednarz, Vanessa N; Rix, Laura; Foster, Rachel A; Al-Rshaidat, Mamoon M D; Wild, Christian

    2016-09-01

    Coral holobionts (i.e., coral-algal-prokaryote symbioses) exhibit dissimilar thermal sensitivities that may determine which coral species will adapt to global warming. Nonetheless, studies simultaneously investigating the effects of warming on all holobiont members are lacking. Here we show that exposure to increased temperature affects key physiological traits of all members (herein: animal host, zooxanthellae and diazotrophs) of both Stylophora pistillata and Acropora hemprichii during and after thermal stress. S. pistillata experienced severe loss of zooxanthellae (i.e., bleaching) with no net photosynthesis at the end of the experiment. Conversely, A. hemprichii was more resilient to thermal stress. Exposure to increased temperature (+ 6°C) resulted in a drastic increase in daylight dinitrogen (N2 ) fixation, particularly in A. hemprichii (threefold compared with controls). After the temperature was reduced again to in situ levels, diazotrophs exhibited a reversed diel pattern of activity, with increased N2 fixation rates recorded only in the dark, particularly in bleached S. pistillata (twofold compared to controls). Concurrently, both animal hosts, but particularly bleached S. pistillata, reduced both organic matter release and heterotrophic feeding on picoplankton. Our findings indicate that physiological plasticity by coral-associated diazotrophs may play an important role in determining the response of coral holobionts to ocean warming. © 2016 Society for Applied Microbiology and John Wiley & Sons Ltd.

  14. Influence of structural habitat use on the thermal ecology of Gonatodes humeralis (Squamata: Gekkonidae from a transitional forest in Maranhão, Brazil

    Directory of Open Access Journals (Sweden)

    Jivanildo P. Miranda

    2010-02-01

    Full Text Available We studied the structural habitat use and the thermal ecology of Gonatodes humeralis (Guichenot, 1855 in São Luís, Maranhão, Brazil, to examine intersexual differences in the use of perch features and to simultaneously analyze reciprocal differences on thermal ecology between the sexes. Gonatodes humeralis body temperature was strongly correlated with environmental temperatures (air and substrate, but air temperature had an additional effect on the males' body temperatures after removing the effect of the substrate temperature. Males and females differed significantly in perch height use above ground (males perched higher but the sexes did not differ in the trunk perimeter used. Gonatodes humeralis tended to use the larger tree trunks available in its environment and selected trunks with deeper leaf litter at the base. It is hypothesized that choosing tree trunks with deeper leaf litter is a defensive behavior against predation.

  15. Modeling of the thermal influence of fires on the physicochemical properties and microbial activity of litter in cryogenic soils

    Science.gov (United States)

    Masyagina, O. V.; Tokareva, I. V.; Prokushkin, A. S.

    2014-08-01

    Periodic surface fires in the cryolithozone (the northern taiga subzone) are the main factor determining the qualitative and quantitative characteristics of the soil organic matter. The specific features of the changes in the physicochemical parameters and microbial activity of the organic horizons in the cryogenic soils under larch forests of the northern taiga after the impact of high temperatures were revealed. The temperatures of fires of different intensity were simulated in laboratory conditions. The thermal impact on the litter organic matter during the surface fires may increase the CO2 emission from the surface of the soil in the postfire communities due to the destruction of organic compounds only for a short time. After fires of high intensity with strong mineralization of the litters, during a period of more than 1 month, the pyrogenic effect on the organic horizons of the soils under the larch forests of the cryolithozone determined the reduction of the CO2 emissions in the freshly burned areas as compared to the intact stands.

  16. Direct profiling of environmental microbial populations by thermal dissociation analysis of native rRNAs hybridized to oligonucleotide microarrays

    NARCIS (Netherlands)

    Fantroussi, El S.; Urakawa, H.; Bernhard, A.E.; Kelly, J.J.; Noble, P.A.; Smidt, H.; Yershov, G.M.; Stahl, D.A.

    2003-01-01

    Oligonucleotide microarrays were used to profile directly extracted rRNA from environmental microbial populations without PCR amplification. In our initial inspection of two distinct estuarine study sites, the hybridization patterns were reproducible and varied between estuarine sediments of

  17. Fine-scale variability of forest soil fungal communities in two contrasting habitat series in northern Idaho, USA identified with microbial metagenomics

    Science.gov (United States)

    Amy Ross-Davis; Jane E. Stewart; Matt Settles; John W. Hanna; John D. Shaw; Andrew T. Hudak; Deborah S. Page-Dumroese; Ned B. Klopfenstein

    2016-01-01

    Forests are home to some of the most complex microbial communities (Fierer et al. 2012) which drive biogeochemical cycles (Clemmensen et al. 2013; van der Heijden et al. 2008) and account for substantial terrestrial biomass (Nielsen et al. 2011). Fungi, through their ecological roles as decomposers, mutualists, or pathogens, are particularly important in...

  18. Enrichment and genome sequence of the group I.1a ammonia-oxidizing Archaeon "Ca. Nitrosotenuis uzonensis" representing a clade globally distributed in thermal habitats.

    Directory of Open Access Journals (Sweden)

    Elena V Lebedeva

    Full Text Available The discovery of ammonia-oxidizing archaea (AOA of the phylum Thaumarchaeota and the high abundance of archaeal ammonia monooxygenase subunit A encoding gene sequences in many environments have extended our perception of nitrifying microbial communities. Moreover, AOA are the only aerobic ammonia oxidizers known to be active in geothermal environments. Molecular data indicate that in many globally distributed terrestrial high-temperature habits a thaumarchaeotal lineage within the Nitrosopumilus cluster (also called "marine" group I.1a thrives, but these microbes have neither been isolated from these systems nor functionally characterized in situ yet. In this study, we report on the enrichment and genomic characterization of a representative of this lineage from a thermal spring in Kamchatka. This thaumarchaeote, provisionally classified as "Candidatus Nitrosotenuis uzonensis", is a moderately thermophilic, non-halophilic, chemolithoautotrophic ammonia oxidizer. The nearly complete genome sequence (assembled into a single scaffold of this AOA confirmed the presence of the typical thaumarchaeotal pathways for ammonia oxidation and carbon fixation, and indicated its ability to produce coenzyme F420 and to chemotactically react to its environment. Interestingly, like members of the genus Nitrosoarchaeum, "Candidatus N. uzonensis" also possesses a putative artubulin-encoding gene. Genome comparisons to related AOA with available genome sequences confirmed that the newly cultured AOA has an average nucleotide identity far below the species threshold and revealed a substantial degree of genomic plasticity with unique genomic regions in "Ca. N. uzonensis", which potentially include genetic determinants of ecological niche differentiation.

  19. The deep subsurface biosphere in igneous ocean crust: frontier habitats for microbiological exploration

    Directory of Open Access Journals (Sweden)

    Katrina eEdwards

    2012-02-01

    Full Text Available We discuss ridge flank environments in the ocean crust as habitats for subseafloor microbial life. Oceanic ridge flanks, areas far from the magmatic and tectonic influence of seafloor spreading, comprise one of the largest and least explored microbial habitats on the planet. We describe the nature of the ridge flank crustal environments, and present a framework for delineating a continuum of conditions and processes that are likely to be important for defining subseafloor microbial "provinces." The basis for this framework is three governing sets of conditions that help to determine the nature of subseafloor biomes: crustal age, extent of fluid flow, and thermal state. We present a brief overview of subseafloor conditions, within the context of these three characteristics, for five field sites where microbial studies have been done, are underway, or have been proposed. Technical challenges remain and likely will limit progress in studies of microbial ridge-flank ecosystems, which is why it is vital to select and design future studies so as to leverage as much general understanding as possible. A characterization framework such as presented in this paper, perhaps including alternative or additional physical or chemical characteristics, is essential for achieving the greatest benefit from multidisciplinary microbial investigations of the oceanic ridge flanks.

  20. Habitat pollution and thermal regime modify molecular stress responses to elevated temperature in freshwater mussels (Anodonta anatina: Unionidae)

    Energy Technology Data Exchange (ETDEWEB)

    Falfushynska, H.; Gnatyshyna, L.; Yurchak, I. [Research Laboratory of Comparative Biochemistry and Molecular Biology, Ternopil National Pedagogical University, Kryvonosa Str 2, 46027 Ternopil (Ukraine); Ivanina, A. [Department of Biological Sciences, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223 (United States); Stoliar, O. [Research Laboratory of Comparative Biochemistry and Molecular Biology, Ternopil National Pedagogical University, Kryvonosa Str 2, 46027 Ternopil (Ukraine); Sokolova, I., E-mail: isokolov@uncc.edu [Department of Biological Sciences, University of North Carolina at Charlotte, 9201 University City Blvd., Charlotte, NC 28223 (United States)

    2014-12-01

    Elevated temperature and pollution are common stressors in freshwater ecosystems. We study cellular stress response to acute warming in Anodonta anatina (Unionidae) from sites with different thermal regimes and pollution levels: a pristine area and an agriculturally polluted site with normal temperature regimes (F and A, respectively) and a polluted site with elevated temperature (N) from the cooling pond of an electrical power plant. Animals were exposed to different temperatures for 14 days and stress response markers were measured in gills, digestive gland and hemocytes. Mussels from site N and A had elevated background levels of lactate dehydrogenase activity indicating higher reliance on anaerobic metabolism for ATP production and/or redox maintenance. Exposure to 25 °C and 30 °C induced oxidative stress (indicated by elevated levels of lipid peroxidation products) in digestive gland and gills of mussels from A and F sites, while in mussels from N sites elevated oxidative stress was only apparent at 30 °C. Temperature-induced changes in levels of antioxidants (superoxide dismutase, metallothioneins and glutathione) were tissue- and population-specific. Acute warming led to destabilization of lysosomal membranes and increased frequencies of nuclear lesions in mussels from F and A sites but not in their counterparts from N site. Elevated temperature led to an increase in the frequency of micronuclei in hemocytes in mussels from F and A sites at 25 °C and 30 °C and in mussels from N site at 30 °C. The mussels from N site also demonstrated better survival at elevated temperature (30 °C) than their counterparts from the F and A sites. Taken together, these data indicate that long-term acclimation and/or adaptation of A. anatina to elevated temperatures result in increased thermotolerance and alleviate stress response to moderate temperature rise. In contrast, extreme warming (30 °C) is harmful to mussels from all populations indicating limit to this induced

  1. Marine microbial symbiosis heats up: the phylogenetic and functional response of a sponge holobiont to thermal stress

    OpenAIRE

    Fan, Lu; Liu, Michael; Simister, Rachel; Webster, Nicole S; Thomas, Torsten

    2013-01-01

    Large-scale mortality of marine invertebrates is a major global concern for ocean ecosystems and many sessile, reef-building animals, such as sponges and corals, are experiencing significant declines through temperature-induced disease and bleaching. The health and survival of marine invertebrates is often dependent on intimate symbiotic associations with complex microbial communities, yet we have a very limited understanding of the detailed biology and ecology of both the host and the symbio...

  2. Effects of thermal and enzymatic treatments and harvesting time on the microbial quality and chemical composition of fibre hemp (Cannabis sativa L.)

    DEFF Research Database (Denmark)

    Nykter, M.; Kymalainen, H.R.; Thomsen, Anne Belinda

    2008-01-01

    The aim of the present study was to examine the effects of pectinase enzyme treatment followed by thermal treatments (steam explosion and dry heating) on the microbial quality and chemical composition of hemp fibres. Before these treatments, the fibres were separated manually from the stems...... materials. Dry heating had no effect on mould and bacterial counts at temperatures below 120 degrees C and durations less than 60 min. The chemical composition was affected by the enzymatic treatment due to extraction and degradation of water-soluble components, pectin and ash. Thus the cellulose content...... harvested after stand retting in the field before frost, after early frost or in the following spring. The enzymatic treatment of hemp promoted growth of moulds on the fibres (500-fold increase in colony-forming units (cfu)), whereas steam explosion reduced the amount of moulds to a relatively constant...

  3. A high-pressure thermal gradient block for investigating microbial activity in multiple deep-sea samples

    DEFF Research Database (Denmark)

    Kallmeyer, J.; Ferdelman, TG; Jansen, KH

    2003-01-01

    Details about the construction and use of a high-pressure thermal gradient block for the simultaneous incubation of multiple samples are presented. Most parts used are moderately priced off-the-shelf components that easily obtainable. In order to keep the pressure independent of thermal expansion...... of the sample vessels, a back-pressure system with a constant leak rate was installed. Pressure is applied through high-pressure liquid chromatography (HPLC) pumps that run in constant pressure mode with variable flow rate, thereby regulating any pressure fluctuations. The device allows incubations along a wide...

  4. PCB concentrations in lake trout (Salvelinus namaycush) are correlated to habitat use and lake characteristics.

    Science.gov (United States)

    Guildford, S J; Muir, D C G; Houde, M; Evans, M S; Kidd, K A; Whittle, D M; Drouillard, K; Wang, X; Anderson, M R; Bronte, C R; Devault, D S; Haffner, D; Payne, J; Kling, H J

    2008-11-15

    This study considers the importance of lake trout habitat as a factor determining persistent organochlorine (OC) concentration. Lake trout is a stenothermal, cold water species and sensitive to hypoxia. Thus, factors such as lake depth, thermal stratification, and phosphorus enrichment may determine not only which lakes can support lake trout but may also influence among-lake variability in lake trout population characteristics including bioaccumulation of OCs. A survey of 23 lakes spanning much of the natural latitudinal distribution of lake trout provided a range of lake trout habitat to test the hypothesis that lake trout with greater access to littoral habitat for feeding will have lower concentrations of OCs than lake trout that are more restricted to pelagic habitat. Using the delta13C stable isotope signature in lake trout as an indicator of influence of benthic littoral feeding, we found a negative correlation between lipid-corrected delta13C and sigmaPCB concentrations supporting the hypothesis that increasing accessto littoral habitat results in lower OCs in lake trout. The prominence of mixotrophic phytoplankton in lakes with more contaminated lake trout indicated the pelagic microbial food web may exacerbate the biomagnification of OCs when lake trout are restricted to pelagic feeding. A model that predicted sigmaPCB in lake trout based on lake area and latitude (used as proximate variables for proportion of littoral versus pelagic habitat and accessibility to littoral habitat respectively) explained 73% of the variability in sigmaPCBs in lake trout in the 23 lakes surveyed.

  5. Combined high-pressure and thermal treatments for processing of tomato puree : evaluation of microbial inactivation and quality parameters

    NARCIS (Netherlands)

    Krebbers, B.; Matser, A.M.; Hoogerwerf, S.W.; Moezelaar, R.; Tomassen, M.M.M.; Berg, van den R.W.

    2003-01-01

    The effects of combined high-pressure thermal treatments on consistency, viscosity, colour, lycopene content, enzyme activity and micro-organisms were determined, and compared to conventional pasteurisation and sterilisation processes of tomato puree. High-pressure processing at ambient temperature

  6. Pore-water chemistry from the ICDP-USGS coer hole in the Chesapeake Bay impact structure--Implications for paleohydrology, microbial habitat, and water resources

    Science.gov (United States)

    Sanford, Ward E.; Voytek, Mary A.; Powars, David S.; Jones, Blair F.; Cozzarelli, Isabelle M.; Eganhouse, Robert P.; Cockell, Charles S.

    2009-01-01

    We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between fresh and saline water from 100 to 500 m depth in the post-impact sediment section, and an underlying syn-impact section that is almost entirely filled with brine. The presence of brine in the lowermost post-impact section and the trend in the dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting its occurrence may be common in the inner crater. However, groundwater flow conditions in the structure may reduce the salt-water-intrusion hazard associated with the brine.

  7. Pore-water chemistry from the ICDP-USGS core hole in the Chesapeake Bay impact structure-Implications for paleohydrology, microbial habitat, and water resources

    Science.gov (United States)

    Sanford, W.E.; Voytek, M.A.; Powars, D.S.; Jones, B.F.; Cozzarelli, I.M.; Cockell, C.S.; Eganhouse, R.P.

    2009-01-01

    We investigated the groundwater system of the Chesapeake Bay impact structure by analyzing the pore-water chemistry in cores taken from a 1766-m-deep drill hole 10 km north of Cape Charles, Virginia. Pore water was extracted using high-speed centrifuges from over 100 cores sampled from a 1300 m section of the drill hole. The pore-water samples were analyzed for major cations and anions, stable isotopes of water and sulfate, dissolved and total carbon, and bioavailable iron. The results reveal a broad transition between freshwater and saline water from 100 to 500 m depth in the postimpact sediment section, and an underlying synimpact section that is almost entirely filled with brine. The presence of brine in the lowermost postimpact section and the trend in dissolved chloride with depth suggest a transport process dominated by molecular diffusion and slow, compaction-driven, upward flow. Major ion results indicate residual effects of diagenesis from heating, and a pre-impact origin for the brine. High levels of dissolved organic carbon (6-95 mg/L) and the distribution of electron acceptors indicate an environment that may be favorable for microbial activity throughout the drilled section. The concentration and extent of the brine is much greater than had previously been observed, suggesting that its occurrence may be common in the inner crater. However, groundwater-flow conditions in the structure may reduce the saltwater-intrusion hazard associated with the brine. ?? 2009 The Geological Society of America.

  8. Vacant habitats in the Universe.

    Science.gov (United States)

    Cockell, Charles S

    2011-02-01

    The search for life on other planets usually makes the assumption that where there is a habitat, it will contain life. On the present-day Earth, uninhabited habitats (or vacant habitats) are rare, but might occur, for example, in subsurface oils or impact craters that have been thermally sterilized in the past. Beyond Earth, vacant habitats might similarly exist on inhabited planets or on uninhabited planets, for example on a habitable planet where life never originated. The hypothesis that vacant habitats are abundant in the Universe is testable by studying other planets. In this review, I discuss how the study of vacant habitats might ultimately inform an understanding of how life has influenced geochemical conditions on Earth. Copyright © 2010 Elsevier Ltd. All rights reserved.

  9. Thermal intensification of microbial Fe(II)/Fe(III) redox cycling in a pristine shallow sand aquifer on the Canadian Shield.

    Science.gov (United States)

    Shirokova, V L; Enright, A M L; Kennedy, C B; Ferris, F G

    2016-12-01

    This investigation evaluates spatial relationships between summer (July) groundwater temperatures and Fe(II)/Fe(III) biogeochemical cycling over a five year period in a shallow pristine sand aquifer at Meilleurs Bay near Deep River, Ontario, Canada. A warm subsurface thermal island of 12.5-16.1 °C, compared to background conditions of 10-11 °C, was manifest in contour maps of average groundwater temperature over the study period. The warm zone coincided with an area of convergent groundwater flow, implicating horizontal heat transfer by advective convection as the reason for elevated temperatures. Additionally, high concentrations of dissolved Fe(II) and Fe(III) overlapped the warm thermal island, indicative of increased rates of bacterial Fe(II)-oxidation and Fe(III)-reduction. A depletion in the modal abundance of Fe(II)-bearing minerals, notably amphibole and biotite, inside the area of the warm thermal island was also observed, suggesting enhanced mineral dissolution owing to chemoautotrophic Fe(II)-oxidation coupled to the reduction and fixation of dissolved inorganic carbon as biomass. Throughout the aquifer, redox conditions were poised in terms of Eh and pH close to equilibrium with respect to the Fe(II)/Fe(OH)3 couple, feasibly enabling simultaneous bacterial Fe(II)-oxidation and Fe(III)-reduction with an adequate supply of electron acceptors and donors, respectively. The significance of higher groundwater temperature as a determinant of elevated dissolved Fe(II) and Fe(III) concentrations induced by thermal intensification of microbial biogeochemical activities yielded Pearson product-moment correlations in which temperature alone, as a single independent variable, explains almost 30 to nearly 60 percent of the variation in the measured dissolved Fe(II) and Fe(III) concentrations in the groundwater. These results emphasize the important influence of thermal conditions on biogeochemical processes in aquifers coupled to the development of steep

  10. Microbial modeling of thermal resistance of Alicyclobacillus acidoterrestris CRA7152 spores in concentrated orange juice with nisin addition

    Science.gov (United States)

    Peña, Wilmer Edgard Luera; de Massaguer, Pilar Rodriguez; Teixeira, Luciano Quintão

    2009-01-01

    The nisin effect on thermal death of Alicyclobacillus acidoterrestris CRA 7152 spores in concentrated orange juice (64°Brix) was studied. Concentrations of 0, 50, 75 and 100 IU of nisin/ml juice, at temperatures of 92, 95, 98 and 102°C were evaluated. The quadratic polynomial model was used to analyze the effects of the factors and their interaction. Verification of surviving spores was carried out through plating in K medium (pH 3.7). The results showed that the D values without nisin addition were 25.5, 12.9, 6.1 and 2.3 min for 92, 95, 98 and 102°C respectively. With addition of nisin into the juice there was a drop of heat resistance as the concentration was increased at a same temperature. With 30, 50, 75, 100 and 150 IU/ml at 95°C, the D values were 12.34, 11.38, 10.49, 9.49 and 9.42 min respectively, showing that a decrease in the D value up to 27% can be obtained. The second order polynomial model established with r2 = 0.995 showed that the microorganism resistance was affected by the action of temperature followed by the nisin concentration. Nisin therefore is an alternative for reducing the rigor of the A. acidoterrestris CRA 7152 thermal treatment. PMID:24031405

  11. Biological functioning of PAH-polluted and thermal desorption-treated soils assessed by fauna and microbial bioindicators.

    Science.gov (United States)

    Cébron, Aurélie; Cortet, Jérôme; Criquet, Stéven; Biaz, Asmaa; Calvert, Virgile; Caupert, Cécile; Pernin, Céline; Leyval, Corinne

    2011-11-01

    A large number of soil bioindicators were used to assess biological diversity and activity in soil polluted with polycyclic aromatic hydrocarbons (PAHs) and the same soil after thermal desorption (TD) treatment. Abundance and biodiversity of bacteria, fungi, protozoa, nematodes and microarthropods, as well as functional parameters such as enzymatic activities and soil respiration, were assessed during a two year period of in situ monitoring. We investigated the influence of vegetation (spontaneous vegetation and Medicago sativa) and TD treatment on biological functioning. Multivariate analysis was performed to analyze the whole data set. A principal response curve (PRC) technique was used to evaluate the different treatments (various vegetation and contaminated vs. TD soil) contrasted with control (bare) soil over time. Our results indicated the value of using a number of complementary bioindicators, describing both diversity and functions, to assess the influence of vegetation on soil and discriminate polluted from thermal desorption (TD)-treated soil. Plants had an influence on the abundance and activity of all organisms examined in our study, favoring the whole trophic chain development. However, although TD-treated soil had a high abundance and diversity of microorganisms and fauna, enzymatic activities were weak because of the strong physical and chemical modifications of this soil. Copyright © 2011 Institut Pasteur. Published by Elsevier Masson SAS. All rights reserved.

  12. Microbial co-occurrence relationships in the human microbiome

    National Research Council Canada - National Science Library

    Faust, Karoline; Sathirapongsasuti, J Fah; Izard, Jacques; Segata, Nicola; Gevers, Dirk; Raes, Jeroen; Huttenhower, Curtis

    2012-01-01

    .... The initial Human Microbiome Project (HMP) cohort, comprising 239 individuals and 18 different microbial habitats, provides an unprecedented resource to detect, catalog, and analyze such relationships...

  13. Effects of thermal and enzymatic treatments and harvesting time on the microbial quality and chemical composition of fibre hemp (Cannabis sativa L.)

    Energy Technology Data Exchange (ETDEWEB)

    Nykter, Minna; Kymaelaeinen, Hanna-Riitta; Sjoeberg, Anna-Maija [Department of Agrotechnology, University of Helsinki, P.O. Box 28, FI-00014 University of Helsinki (Finland); Thomsen, Anne Belinda; Thygesen, Anders [Biosystems Department, Risoe National Laboratory, P.O. Box 49, DK-4000 Roskilde (Denmark); Lilholt, Hans [Materials Research Department, Risoe National Laboratory, P.O. Box 49, DK-4000 Roskilde (Denmark); Koponen, Hilkka [Department of Applied Biology, Section of Plant Pathology, University of Helsinki, P.O. Box 27, FI-00014 University of Helsinki (Finland)

    2008-05-15

    The aim of the present study was to examine the effects of pectinase enzyme treatment followed by thermal treatments (steam explosion and dry heating) on the microbial quality and chemical composition of hemp fibres. Before these treatments, the fibres were separated manually from the stems harvested after stand retting in the field before frost, after early frost or in the following spring. The enzymatic treatment of hemp promoted growth of moulds on the fibres (500-fold increase in colony-forming units (cfu)), whereas steam explosion reduced the amount of moulds to a relatively constant level of 10{sup 2} cfu/g dw. The amount of bacteria was not markedly affected by enzymatic treatment but was reduced tenfold after steam explosion. Steam explosion is thereby a potentially good process for the production of hemp fibres with low fungal contamination, which can be of importance in insulation materials. Dry heating had no effect on mould and bacterial counts at temperatures below 120 C and durations less than 60 min. The chemical composition was affected by the enzymatic treatment due to extraction and degradation of water-soluble components, pectin and ash. Thus the cellulose content increased by 6% w/w to 67-70% w/w. Steam explosion of the untreated hemp fibres increased the cellulose content to 74% w/w, whereas steam explosion of enzymatically treated hemp increased the cellulose content to 78% w/w. (author)

  14. Habitat Observations

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — These data provide information on the relationship between California red-legged frogs and their habitat in a unique ecosystem to better conserve this threatened...

  15. The Microbial Olympics

    Science.gov (United States)

    Youle, Merry; Rohwer, Forest; Stacy, Apollo; Whiteley, Marvin; Steel, Bradley C.; Delalez, Nicolas J.; Nord, Ashley L.; Berry, Richard M.; Armitage, Judith P.; Kamoun, Sophien; Hogenhout, Saskia; Diggle, Stephen P.; Gurney, James; Pollitt, Eric J. G.; Boetius, Antje; Cary, S. Craig

    2014-01-01

    Every four years, the Olympic Games plays host to competitors who have built on their natural talent by training for many years to become the best in their chosen discipline. Similar spirit and endeavour can be found throughout the microbial world, in which every day is a competition to survive and thrive. Microorganisms are trained through evolution to become the fittest and the best adapted to a particular environmental niche or lifestyle, and to innovate when the ‘rules of the game’ are changed by alterations to their natural habitats. In this Essay, we honour the best competitors in the microbial world by inviting them to take part in the inaugural Microbial Olympics. PMID:22796885

  16. Phylogenetic and functional analysis of metagenome sequence from high-temperature archaeal habitats demonstrate linkages between metabolic potential and geochemistry

    Directory of Open Access Journals (Sweden)

    William P. Inskeep

    2013-05-01

    Full Text Available Geothermal habitats in Yellowstone National Park (YNP provide an unparalled opportunity to understand the environmental factors that control the distribution of archaea in thermal habitats. Here we describe, analyze and synthesize metagenomic and geochemical data collected from seven high-temperature sites that contain microbial communities dominated by archaea relative to bacteria. The specific objectives of the study were to use metagenome sequencing to determine the structure and functional capacity of thermophilic archaeal-dominated microbial communities across a pH range from 2.5 to 6.4 and to discuss specific examples where the metabolic potential correlated with measured environmental parameters and geochemical processes occurring in situ. Random shotgun metagenome sequence (~40-45 Mbase Sanger sequencing per site was obtained from environmental DNA extracted from high-temperature sediments and/or microbial mats and subjected to numerous phylogenetic and functional analyses. Analysis of individual sequences (e.g., MEGAN and G+C content and assemblies from each habitat type revealed the presence of dominant archaeal populations in all environments, 10 of whose genomes were largely reconstructed from the sequence data. Analysis of protein family occurrence, particularly of those involved in energy conservation, electron transport and autotrophic metabolism, revealed significant differences in metabolic strategies across sites consistent with differences in major geochemical attributes (e.g., sulfide, oxygen, pH. These observations provide an ecological basis for understanding the distribution of indigenous archaeal lineages across high temperature systems of YNP.

  17. Dehydration, with and without heat, in kangaroos from mesic and arid habitats: different thermal responses including varying patterns in heterothermy in the field and laboratory.

    Science.gov (United States)

    Dawson, Terence J; Blaney, Cyntina E; McCarron, Hugh C K; Maloney, Shane K

    2007-10-01

    Field data showing the daily patterns in body temperature (T(b)) of kangaroos in hot, arid conditions, with and without water, indicate the use of adaptive heterothermy, i.e. large variation in T(b). However, daily T(b) variation was greater in the Eastern Grey Kangaroo (Macropus giganteus), a species of mesic origin, than in the desert-adapted Red Kangaroo (Macropus rufus). The nature of such responses was studied by an examination of their thermal adjustments to dehydration in thermoneutral temperatures (25 degrees C) and at high temperature (45 degrees C) via the use of tame, habituated animals in a climate chamber. At the same level of dehydration M. rufus was less impacted, in that its T(b) changed less than that for M. giganteus while it evaporated significantly less water. At a T(a) of 45 degrees C with water restriction T(b) reached 38.9 +/- 0.3 degrees C in M. rufus compared with 40.2 +/- 0.4 degrees C for M. giganteus. The ability of M. rufus to reduce dry conductance in the heat while dehydrated was central to its superior thermal control. While M. giganteus showed more heterothermy, i.e. its T(b) varied more, this seemed due to a lower tolerance of dehydration in concert with a strong thermal challenge. The benefits of heterothermy to M. giganteus were also limited because of thermal (Q(10)) effects on metabolic heat production and evaporative heat loss. The impacts of T(b) on heat production were such that low morning T(b)'s seen in the field may be associated with energy saving, as well as water saving. Kangaroos respond to dehydration and heat similarly to many ungulates, and it is apparent that the accepted notions about adaptive heterothermy in large desert mammals may need revisiting.

  18. Continuation of studies on thermoregulation of fish and turtles in thermally stressed habitats. Annual progress report, 1 October 1979-30 September 1980

    Energy Technology Data Exchange (ETDEWEB)

    Spotila, J.R.

    1980-05-01

    Fundamental and realized climate spaces were calculated for the turtle Chrysemys scripta. These allow predictions about the effect of microclimate and thermal effluents on the behavior of these animals to be made. A conceptual model to define the biophysical-behavioral thermoregulatory mechanisms employed by this turtle is being finalized. Operative environmental temperature (T/sub e/) is a good predictor of the basking behavior of turtles. T/sub e/ is positively related to visible and thermal radiation and air temperature. Turtles generally do not bask until T/sub e/ exceeds 28/sup 0/C, thus implicating thermoregulation as a major factor in determining the basking behavior of C. scripta. Water temperature was very important in determining the distribution of largemouth bass, Micropterus salmoides, in a South Carolina reservoir receiving thermal effluent from a nuclear reactor. Bass were restricted in movement by lethal water temperatures, selecting temperatures close to 30/sup 0/C and avoiding temperatures above 31/sup 0/C. Under normal, unheated conditions, bass dispersed throughout the reservoir. During reactor operation, hot water at temperatures lethal to fish (approx. 55/sup 0/C), forced bass to retreat to refuges in two coves and a deep spring. Distribution of bass varied seasonally. Multichannel radio transmitters were surgically implanted in free ranging fish, permitting the telemetry of temperatures from five parts of the body and from surrounding water. In general, body temperatures followed water temperatures closely, but rapidly changing temperatures produced lags between body temperatures and water of as much as 3.5/sup 0/C. (ERB)

  19. Continuation of studies on thermoregulation of fish and turtles in thermally stressed habitats. Summary progress report, 1 October 1977-30 September 1980

    Energy Technology Data Exchange (ETDEWEB)

    Spotila, J.R.

    1980-05-01

    Biophysical-behavioral-ecological models have been completed to explain the behavioral thermoregulation of largemouth bass (Micropterus salmoides) and turtles (Chrysemys scripta). Steady state and time dependent mathematical models accurately predict the body temperatures of largemouth bass. Field experiments using multichannel radio transmitters have provided temperatures of several body compartments of free ranging bass in their natural habitat. Initial studies have been completed to describe the behavioral thermoregulation of bass in a reactor cooling reservoir. Energy budgets, fundamental climate spaces, and realized climate spaces have been completed for the turtle, C. scripta. We have described the behavioral thermoregulation of C. scripta in Par Pond, S.C. and have measured its movements, home ranges and population levels in heated and unheated arms of the reservoir. Operative environmental temperature is a good predictor of the basking behavior of this turtle. A new synthesis explained the evolution of thermoregulatory strategies among animals. Laboratory experiments clarified the effects of movement, diving and temperature on the blood flow of alligators. Other experiments defined the role of boundary layers in controlling the evaporation of water from the surfaces of turtles and alligators in still and moving air. Nutritional status may be an important factor affecting the thermoregulatory behavior of turtles.

  20. Continuation of studies on thermoregulation of fish and turtles in thermally stressed habitats. Annual progress report, 1 October 1978-30 September 1979

    Energy Technology Data Exchange (ETDEWEB)

    Spotila, J.R.

    1979-06-01

    A time dependent mathematical model accurately predicts heart, brain, and gut temperatures of largemouth bass. Body diameter, insulation thickness, and tissue thermal conductivity are controlling variables in the transfer of heat between a fish and water. Fish metabolic rate and water velocity across fish surfaces do not appreciably affect heat transfer rates. Multichannel temperature transmitters telemeter body temperatures of free swimming bass in Pond C on the Savannah River Plant while the behavior of those fish and other bass is recorded by an observer. Field studies of the home ranges and movements of turtles in Par Pond on the Savannah River Plant are completed. We have recorded the movements of 30 individuals fitted with radio transmitters. Distinct differences are apparent in the behavior of turtles in areas affected by heated effluents as compared to those in control areas. Calculations and theoretical analysis of the transient energy exchange of turtles are continuing. Laboratory experiments using /sup 133/Xe indicate that blood flow in the muscles and skin of alligators increases 2 to 6 fold during movement. Relative variation is similar in magnitude to that seen in human muscle. Evaporative water loss from alligators decreases as body size increases. The ratios of respiratory to cutaneous water loss are 1.80 at 5/sup 0/C, 1.18 at 25/sup 0/C and 0.85 at 35/sup 0/C. Boundary layer resistances to evaporative water loss are 6 fold less than predicted by calculations of aerodynamic boundary layers. Body size is a primary factor in determining the thermoregulatory strategy that is to be used by a given animal.Operative environmental temperatures (T/sub e/) are as high as 60/sup 0/C for a turtle basking on a log in the sun. In a rainstorm T/sub e/ drops to 18/sup 0/C. Experiments to measure T/sub e/ for turtles in normal and thermally affected areas are now continuing on the Savannah River Plant. (ERB)

  1. Microbial Monitoring of the International Space Station

    Science.gov (United States)

    Pierson, Duane L.; Botkin, Douglas J.; Bruce, Rebekah J.; Castro, Victoria A.; Smith, Melanie J.; Oubre, Cherie M.; Ott, C. Mark

    2013-01-01

    microbial growth. Air filtration can dramatically reduce the number of airborne bacteria, fungi, and particulates in spacecraft breathing air. Waterborne bacteria can be reduced to acceptable levels by thermal inactivation of bacteria during water processing, along with a residual biocide, and filtration at the point of use can ensure safety. System design must include onboard capability to achieve recovery of the system from contamination. Robust housekeeping procedures that include periodic cleaning and disinfection will prevent high levels of microbial growth on surfaces. Food for consumption in space must be thoroughly tested for excessive microbial content and pathogens before launch. Thorough preflight examination of flight crews, consumables, payloads, and the environment can greatly reduce pathogens in spacecraft. Many of the lessons learned from the Space Shuttle and previous programs were applied in the early design phase of the International Space Station, resulting in the safest space habitat to date. This presentation describes the monitoring program for the International Space Station and will summarize results from preflight and on-orbit monitoring.

  2. Microbial ecology of terrestrial Antarctica: Are microbial systems at risk from human activities?

    Energy Technology Data Exchange (ETDEWEB)

    White, G.J.

    1996-08-01

    Many of the ecological systems found in continental Antarctica are comprised entirely of microbial species. Concerns have arisen that these microbial systems might be at risk either directly through the actions of humans or indirectly through increased competition from introduced species. Although protection of native biota is covered by the Protocol on Environmental Protection to the Antarctic Treaty, strict measures for preventing the introduction on non-native species or for protecting microbial habitats may be impractical. This report summarizes the research conducted to date on microbial ecosystems in continental Antarctica and discusses the need for protecting these ecosystems. The focus is on communities inhabiting soil and rock surfaces in non-coastal areas of continental Antarctica. Although current polices regarding waste management and other operations in Antarctic research stations serve to reduce the introduction on non- native microbial species, importation cannot be eliminated entirely. Increased awareness of microbial habitats by field personnel and protection of certain unique habitats from physical destruction by humans may be necessary. At present, small-scale impacts from human activities are occurring in certain areas both in terms of introduced species and destruction of habitat. On a large scale, however, it is questionable whether the introduction of non-native microbial species to terrestrial Antarctica merits concern.

  3. Thermal effects on microbial composition and microbiologically induced corrosion and mineral precipitation affecting operation of a geothermal plant in a deep saline aquifer.

    Science.gov (United States)

    Lerm, Stephanie; Westphal, Anke; Miethling-Graff, Rona; Alawi, Mashal; Seibt, Andrea; Wolfgramm, Markus; Würdemann, Hilke

    2013-03-01

    The microbial diversity of a deep saline aquifer used for geothermal heat storage in the North German Basin was investigated. Genetic fingerprinting analyses revealed distinct microbial communities in fluids produced from the cold and warm side of the aquifer. Direct cell counting and quantification of 16S rRNA genes and dissimilatory sulfite reductase (dsrA) genes by real-time PCR proved different population sizes in fluids, showing higher abundance of bacteria and sulfate reducing bacteria (SRB) in cold fluids compared with warm fluids. The operation-dependent temperature increase at the warm well probably enhanced organic matter availability, favoring the growth of fermentative bacteria and SRB in the topside facility after the reduction of fluid temperature. In the cold well, SRB predominated and probably accounted for corrosion damage to the submersible well pump and iron sulfide precipitates in the near wellbore area and topside facility filters. This corresponded to lower sulfate content in fluids produced from the cold well as well as higher content of hydrogen gas that was probably released from corrosion, and maybe favored growth of hydrogenotrophic SRB. This study reflects the high influence of microbial populations for geothermal plant operation, because microbiologically induced precipitative and corrosive processes adversely affect plant reliability.

  4. The biology of habitat dominance; can microbes behave as weeds?

    Science.gov (United States)

    Cray, Jonathan A; Bell, Andrew N W; Bhaganna, Prashanth; Mswaka, Allen Y; Timson, David J; Hallsworth, John E

    2013-01-01

    Summary Competition between microbial species is a product of, yet can lead to a reduction in, the microbial diversity of specific habitats. Microbial habitats can resemble ecological battlefields where microbial cells struggle to dominate and/or annihilate each other and we explore the hypothesis that (like plant weeds) some microbes are genetically hard-wired to behave in a vigorous and ecologically aggressive manner. These ‘microbial weeds’ are able to dominate the communities that develop in fertile but uncolonized – or at least partially vacant – habitats via traits enabling them to out-grow competitors; robust tolerances to habitat-relevant stress parameters and highly efficient energy-generation systems; avoidance of or resistance to viral infection, predation and grazers; potent antimicrobial systems; and exceptional abilities to sequester and store resources. In addition, those associated with nutritionally complex habitats are extraordinarily versatile in their utilization of diverse substrates. Weed species typically deploy multiple types of antimicrobial including toxins; volatile organic compounds that act as either hydrophobic or highly chaotropic stressors; biosurfactants; organic acids; and moderately chaotropic solutes that are produced in bulk quantities (e.g. acetone, ethanol). Whereas ability to dominate communities is habitat-specific we suggest that some microbial species are archetypal weeds including generalists such as: Pichia anomala, Acinetobacter spp. and Pseudomonas putida; specialists such as Dunaliella salina, Saccharomyces cerevisiae, Lactobacillus spp. and other lactic acid bacteria; freshwater autotrophs Gonyostomum semen and Microcystis aeruginosa; obligate anaerobes such as Clostridium acetobutylicum; facultative pathogens such as Rhodotorula mucilaginosa, Pantoea ananatis and Pseudomonas aeruginosa; and other extremotolerant and extremophilic microbes such as Aspergillus spp., Salinibacter ruber and Haloquadratum walsbyi

  5. Environmental microarray analyses of Antarctic soil microbial communities

    NARCIS (Netherlands)

    Yergeau, E.; Schoondermark-Stolk, S.A.; Brodie, E.L.; Déjean, S.; DeSantis, T.Z.; Gonçalves, O.; Piceno, Y.M.; Andersen, G.L.; Kowalchuk, G.A.

    2009-01-01

    Antarctic ecosystems are fascinating in their limited trophic complexity, with decomposition and nutrient cycling functions being dominated by microbial activities. Not only are Antarctic habitats exposed to extreme environmental conditions, the Antarctic Peninsula is also experiencing unequalled

  6. Microbial pesticides

    Science.gov (United States)

    Michael L. McManus

    1991-01-01

    Interest in the use of microbial pesticides has intensified because of public concern about the safety of chemical pesticides and their impact in the environment. Characteristics of the five groups of entomopathogens that have potential as microbial pesticides are briefly discussed and an update is provided on research and development activities underway to enhance the...

  7. An Alternative Approach to Non-Log-Linear Thermal Microbial Inactivation: Modelling the Number of Log Cycles Reduction with Respect to Temperature

    Directory of Open Access Journals (Sweden)

    Vasilis Panagiotis Valdramidis

    2005-01-01

    Full Text Available A mathematical approach incorporating the shoulder effect during the quantification of microbial heat inactivation is being developed based on »the number of log cycles of reduction « concept. Hereto, the heat resistance of Escherichia coli K12 in BHI broth has been quantitatively determined in a generic and accurate way by defining the time t for x log reductions in the microbial population, i.e. txD, as a function of the treatment temperature T. Survival data of the examined microorganism are collected in a range of temperatures between 52–60.6 °C. Shoulder length Sl and specific inactivation rate kmax are derived from a mathematical expression that describes a non-log-linear behaviour. The temperature dependencies of Sl and kmax are used for structuring the txD(T function. Estimation of the txD(T parameters through a global identification procedure permits reliable predictions of the time to achieve a pre-decided microbial reduction. One of the parameters of the txD(T function is proposed as »the reference minimum temperature for inactivation«. For the case study considered, a value of 51.80 °C (with a standard error, SE, of 3.47 was identified. Finally, the time to achieve commercial sterilization and pasteurization for the product at hand, i.e. BHI broth, was found to be 11.70 s (SE=5.22, and 5.10 min (SE=1.22, respectively. Accounting for the uncertainty (based on the 90 % confidence intervals, CI a fail-safe treatment of these two processes takes 20.36 s and 7.12 min, respectively.

  8. Microbial Safari.

    Science.gov (United States)

    Wagner, Stephen C.; Stewart, Robert S., Jr.

    2000-01-01

    Introduces an investigative microbiology laboratory activity emphasizing critical thinking and experimental design in which students isolate and characterize a bacterium from a specific habitat. Explains the procedures of the laboratory including safety, sample collection, and isolation. (YDS)

  9. Microbial Paleontology, Mineralogy and Geochemistry of Modern and Ancient Thermal Spring Deposits and Their Recognition on the Early Earth and Mars"

    Science.gov (United States)

    Farmer, Jack D.

    2004-01-01

    The vision of this project was to improve our understanding of the processes by which microbiological information is captured and preserved in rapidly mineralizing sedimentary environments. Specifically, the research focused on the ways in which microbial mats and biofilms influence the sedimentology, geochemistry and paleontology of modem hydrothermal spring deposits in Yellowstone national Park and their ancient analogs. Toward that goal, we sought to understand how the preservation of fossil biosignatures is affected by 1) taphonomy- the natural degradation processes that affect an organism from the time of its death, until its discovery as a fossil and 2) diagenesis- longer-term, post-depositional processes, including cementation and matrix recrystallization, which collectively affect the mineral matrix that contains fossil biosignature information. Early objectives of this project included the development of observational frameworks (facies models) and methods (highly-integrated, interdisciplinary approaches) that could be used to explore for hydrothermal deposits in ancient terranes on Earth, and eventually on Mars.

  10. Patterns and governing forces in aquatic microbial communities

    NARCIS (Netherlands)

    Nold, s.c.; Zwart, G.

    1998-01-01

    In this review we survey recent publications employing molecular techniques to investigate the distribution of microbial species in aquatic environments. We analyzed the occurrence of microbial phyla in freshwater and marine habitats and observed patterns of distribution that could be explained by

  11. EVALUATION OF MICROBIAL SURVIVAL IN EXTRATERRESTRIAL ENVIRONMENTS

    Directory of Open Access Journals (Sweden)

    Betül BULUÇ

    2012-08-01

    Full Text Available In this paper, the space environments where microbial terrestrial life could form and evolve in, were evaluted with the base of the physical and chemical properties. In addition, Earthial microbial life formation conditions in the interstellar medium and the other planets are investigated and the survival of microorganisms in the space environments are questioned. As a result, considering the aspects of terrestrial microbial life, we suggest that the space environment and other planets could not be a habitat for Earthial microorganisms.

  12. Coastal Critical Habitat Designations

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Endangered Species Act (ESA) requires the Federal government to designate critical habitat, areas of habitat essential to the species' conservation, for ESA...

  13. California Condor Critical Habitat

    Data.gov (United States)

    California Department of Resources — These Data identify (in general) the areas where critical habitat for the California Condor occur. Critical habitat for the species consists of the following 10...

  14. EPR study of thermally treated Archean microbial mats analogues and comparison with Archean cherts: towards a possible marker of oxygenic photosynthesis?

    Science.gov (United States)

    Bourbin, M.; Derenne, S.; Westall, F.; Gourier, D.; Gautret, P.; Rouzaud, J.-N.; Robert, F.

    2012-04-01

    The datation of photosynthesis apparition remains an open question nowadays: did oxygenic photosynthesis appear just before the Great Oxidation Event (GOE) of the atmosphere, 2.3 to 2.4 Gyr ago, or does it originate much earlier? It is therefore of uttermost interest to find markers of oxygenic photosynthesis, applicable to samples of archean age. In order to handle this problem, Microcoleus Chtonoplastes cyanobacteria and Chloroflexus-like non-oxygenic photosynthetic bacteria, were studied using Electron Paramagnetic Resonance (EPR) spectroscopy, a high sensitivity technique for the study of organic radicals in mature geological samples (coals, cherts, meteorites...). M. chtonoplastes and Chloroflexus-like bacteria were sampled in mats from the hypersaline lake "La Salada de Chiprana" (Spain), an analogue to an Archean environment, and were submitted to accelerated ageing through cumulative thermal treatments. For thermal treatment temperatures higher than 620° C, a drastic increase in the EPR linewidth of the oxygenic photosynthetic bacteria (M. chtonoplastes) occurred, as compared with the anoxygenic photosynthetic one (Chloroflexus-like). The EPR study of a thermally treated mixture of the two bacteria evidences that this linewidth increase is driven by catalytic reaction at high temperatures on an element selectively fixed by M. chtonoplastes. Based on comparative EDS analyses, Mg is a potential candidate for this catalytic activity but its precise role and the nature of the reaction are still to be determined. The EPR study of organic radicals in chert rocks of ages ranging from 0.42 to 3.5 Gyr, from various localities and that underwent various metamorphisms, revealed a dispersion of the signal width for the most mature samples. This comparative approach between modern bacterial samples and Precambrian cherts leads to propose the EPR linewidth of mature organic matter in cherts as a potential marker of oxygenic photosynthesis. If confirmed, this marker

  15. The Guaymas Basin hiking guide to hydrothermal mounds, chimneys and microbial mats: complex seafloor expressions of subsurface hydrothermal circulation

    Directory of Open Access Journals (Sweden)

    Andreas eTeske

    2016-02-01

    Full Text Available The hydrothermal mats, mounds and chimneys of the southern Guaymas Basin are the surface expression of complex subsurface hydrothermal circulation patterns. In this overview we document the most frequently visited features of this hydrothermal area with photographs, temperature measurements, and selected geochemical data; many of these distinct habitats await characterization of their microbial communities and activities. Microprofiler deployments on microbial mats and hydrothermal sediments show their steep geochemical and thermal gradients at millimeter-scale vertical resolution. Mapping these hydrothermal features and sampling locations within the southern Guaymas Basin suggest linkages to underlying shallow sills and heatflow gradients. Recognizing the inherent spatial limitations of much current Guaymas Basin sampling calls for a wider survey of the entire spreading region.

  16. The airspace is habitat

    Science.gov (United States)

    Diehl, Robert H.

    2013-01-01

    A preconception concerning habitat persists and has gone unrecognized since use of the term first entered the lexicon of ecological and evolutionary biology many decades ago. Specifically, land and water are considered habitats, while the airspace is not. This might at first seem a reasonable, if unintended, demarcation, since years of education and personal experience as well as limits to perception predispose a traditional view of habitat. Nevertheless, the airspace satisfies the definition and functional role of a habitat, and its recognition as habitat may have implications for policy where expanding anthropogenic development of airspace could impact the conservation of species and subject parts of the airspace to formalized legal protection.

  17. Integrated characterization of natural attenuation of a PCE plume after thermal remediation of the source zone - incl. dual isotope and microbial techniques

    DEFF Research Database (Denmark)

    Broholm, Mette Martina

    PCE DNAPL contamination at the former central dry cleaning facility in Rødekro, Denmark, was subject to thermal (steam) source zone remediation in late 2006. A > 2 km long plume of chlorinated ethenes (PCE and chlorinated degradation products) which has migrated downgradient from the source zone...... has not undergone active remediation. A study of the natural degradation within the plume prior to source treatment including stable isotope monitoring was conducted in 2006(-2007) by Hunkeler et al. (2011). This investigation documented complete degradation of PCE via TCE to DCE by reductive...... dechlorination 1-1.5 km downstream the source area, where the plume descends into more reduced groundwater. The objective of the new (2014) study is to evaluate how the source remediation has impacted the plume and in particular the natural attenuation within the plume. A large monitoring campaign including...

  18. Microbial enzymatic activity and thermal effect in a tropical soil treated with organic materials Atividade enzimática da microbiota e efeito térmico em solo tropical tratado com compostos orgânicos

    Directory of Open Access Journals (Sweden)

    Karina Cenciani

    2008-12-01

    Full Text Available Bacteria and fungi are the most active decomposers of organic materials in soil. They directly affect plant nutrient availability, and chemical and physical properties of soils. This investigation aimed at quantifying the effect of several organic materials on microbial activity of a Rhodic Eutrudox. Soil samples were incubated over a period of 91 days with the following organic materials: cattle manure (CM, earthworm humus (HM, and city sewage sludge from Barueri (BA and Franca (FR. The activities of cellulase, protease and urease enzymes, the soil microbial carbon content (by fumigation-extraction method and the exothermal effect were evaluated. Experimental design was randomized and arranged as factorial scheme five treatments x seven samplings with five replications. Organic materials promoted oscillations in microbial carbon (mg C g-1 soil, and enzyme activities - cellulase (µg glucose g-1 soil 24 h-1, protease (mg Tyr g-1 soil 2 h-1, urease (mg NH4+-N g-1 soil 2 h-1 - and the total thermal effect (J g-1 soil, in the following decreasing order: (1 CM - 21.47; 655.90; 49.68; 24.55; 477.90; (2 BA - 12.98; 367.70; 32.76; 10.66; 426.29; (3 FR - 11.60; 273.40; 18.77; 19.35; 368.00; (4 HM - 11.77; 261.00; 17.05; 9.02; 202.79; (5 control. Correlations were obtained between microbial carbon and cellulase and protease activities (r = 0.54; p Bactérias e fungos são os organismos mais ativos na decomposição de compostos orgânicos no solo, afetando diretamente a disponibilidade de nutrientes para as plantas e as propriedades químicas e físicas dos solos. Este estudo quantificou o efeito de diversos compostos orgânicos na atividade microbiana de um Latossolo Vermelho Eutroférrico típico. As amostras de solo foram incubadas durante 91 dias sob os tratamentos: esterco bovino (CM, húmus de minhoca (HM, e os lodos de esgoto de Barueri (BA e Franca (FR. Foram avaliadas as atividades das enzimas celulase, protease e urease, o carbono microbiano do

  19. Microbial co-habitation and lateral gene transfer: what transposases can tell us

    Energy Technology Data Exchange (ETDEWEB)

    Hooper, Sean D.; Mavromatis, Konstantinos; Kyrpides, Nikos C.

    2009-03-01

    Determining the habitat range for various microbes is not a simple, straightforward matter, as habitats interlace, microbes move between habitats, and microbial communities change over time. In this study, we explore an approach using the history of lateral gene transfer recorded in microbial genomes to begin to answer two key questions: where have you been and who have you been with? All currently sequenced microbial genomes were surveyed to identify pairs of taxa that share a transposase that is likely to have been acquired through lateral gene transfer. A microbial interaction network including almost 800 organisms was then derived from these connections. Although the majority of the connections are between closely related organisms with the same or overlapping habitat assignments, numerous examples were found of cross-habitat and cross-phylum connections. We present a large-scale study of the distributions of transposases across phylogeny and habitat, and find a significant correlation between habitat and transposase connections. We observed cases where phylogenetic boundaries are traversed, especially when organisms share habitats; this suggests that the potential exists for genetic material to move laterally between diverse groups via bridging connections. The results presented here also suggest that the complex dynamics of microbial ecology may be traceable in the microbial genomes.

  20. Trends on Habitat Management

    OpenAIRE

    Raluca Giuşcă

    2008-01-01

    According to traditional image, human habitat constitution is the result of natural inter-relations, the fundamental premise of the existence of natural resources, the climate, and the access to more developed proximities for commercial trading. Human habitat represents a complex system, with environmental values, having live and natural components that are inter-related. The dwelling is the fundamental component of the habitat and by relationship with the other components determines the leve...

  1. Trends on Habitat Management

    Directory of Open Access Journals (Sweden)

    Raluca Giuşcă

    2008-01-01

    Full Text Available According to traditional image, human habitat constitution is the result of natural inter-relations, the fundamental premise of the existence of natural resources, the climate, and the access to more developed proximities for commercial trading. Human habitat represents a complex system, with environmental values, having live and natural components that are inter-related. The dwelling is the fundamental component of the habitat and by relationship with the other components determines the level of habitation.

  2. Fundamentals of microbial community resistance and resilience

    Directory of Open Access Journals (Sweden)

    Ashley eShade

    2012-12-01

    Full Text Available Microbial communities are at the heart of all ecosystems, and yet microbial community behavior in disturbed environments remains difficult to measure and predict. Understanding the drivers of microbial community stability, including resistance (insensitivity to disturbance and resilience (the rate of recovery after disturbance is important for predicting community response to disturbance. Here, we provide an overview of the concepts of stability that are relevant for microbial communities. First, we highlight insights from ecology that are useful for defining and measuring stability. To determine whether general disturbance responses exist for microbial communities, we next examine representative studies from the literature that investigated community responses to press (long-term and pulse (short-term disturbances in a variety of habitats. Then we discuss the biological features of individual microorganisms, of microbial populations, and of microbial communities that may govern overall community stability. We conclude with thoughts about the unique insights that systems perspectives - informed by meta-omics data- may provide about microbial community stability.

  3. Fundamentals of Microbial Community Resistance and Resilience

    Science.gov (United States)

    Shade, Ashley; Peter, Hannes; Allison, Steven D.; Baho, Didier L.; Berga, Mercè; Bürgmann, Helmut; Huber, David H.; Langenheder, Silke; Lennon, Jay T.; Martiny, Jennifer B. H.; Matulich, Kristin L.; Schmidt, Thomas M.; Handelsman, Jo

    2012-01-01

    Microbial communities are at the heart of all ecosystems, and yet microbial community behavior in disturbed environments remains difficult to measure and predict. Understanding the drivers of microbial community stability, including resistance (insensitivity to disturbance) and resilience (the rate of recovery after disturbance) is important for predicting community response to disturbance. Here, we provide an overview of the concepts of stability that are relevant for microbial communities. First, we highlight insights from ecology that are useful for defining and measuring stability. To determine whether general disturbance responses exist for microbial communities, we next examine representative studies from the literature that investigated community responses to press (long-term) and pulse (short-term) disturbances in a variety of habitats. Then we discuss the biological features of individual microorganisms, of microbial populations, and of microbial communities that may govern overall community stability. We conclude with thoughts about the unique insights that systems perspectives – informed by meta-omics data – may provide about microbial community stability. PMID:23267351

  4. Microbial Characterization of Internal Active Thermal Control System (IATCS) Hardware Surfaces after Five Years of Operation in the International Space Station

    Science.gov (United States)

    Roman, Monsi C.; Weir, Natalee E.; Wilson, Mark E.; Pyle, Barry H.

    2006-01-01

    A flex hose assembly containing aqueous coolant from the International Space Station (ISS) Internal Active Thermal Control System (IATCS) consisting of a 2 foot section of Teflon hose and quick disconnects (QDs) and a Special Performance Checkout Unit (SPCU) heat exchanger containing separate channels of IATCS coolant and iodinated water used to cool spacesuits and Extravehicular Mobility Units (EMUS) were returned for destructive analyses on Shuttle return to flight mission STS-114. The original aqueous IATCS coolant used in Node 1, the Laboratory Module, and the Airlock consisted of water, borate (pH buffer), phosphate (corrosion control), and silver sulfate (microbiological control) at a pH of 9.5 +/- 0.5. Chemical changes occurred after on-orbit implementation including a decrease to pH 8.4 due to the diffusion of carbon dioxide through the Teflon hoses, an increase in nickel ions due to general corrosion of heat exchanger braze coatings, a decrease in phosphate concentration due to precipitation of nickel phosphate, and the rapid disappearance of silver ions due to deposition on hardware surfaces. Also associated with the coolant chemistry changes was an increase in planktonic microorganisms from less than 100 colony forming units (CFU) per 100 ml to approximately 1 million CFU per 100 ml. Attachment and growth of microorganisms to the system surfaces (biofilm) was suspected due to the levels of planktonic microorganisms in the coolant. Biofilms can reduce coolant flow, reduce heat transfer, amplify degradation of system materials initiated by chemical corrosion, and enhance mineral scale formation.

  5. Effects of Experimental Lead Pollution on the Microbial Communities Associated with Sphagnum fallax (Bryophyta)

    OpenAIRE

    Nguyen Viet, Hung; Gilbert, Daniel; Mitchell, Edward A.D.; Badot, Pierre-Marie; Bernard, Nadine

    2010-01-01

    Ecotoxicological studies usually focus on single microbial species under controlled conditions. As a result, little is known about the responses of different microbial functional groups or individual species to stresses. In an aim to assess the response of complex microbial communities to pollution in their natural habitat, we studied the effect of a simulated lead pollution on the microbial community (bacteria, cyanobacteria, protists, fungi, and micrometazoa) living on Sphagnum fallax. Moss...

  6. Stratification of habitats for identifying habitat selection by Merriam's turkeys

    Science.gov (United States)

    Mark A. Rumble; Stanley H. Anderson

    1992-01-01

    Habitat selection patterns of Merriam’s Turkeys were compared in hierarchical analyses of three levels of habitat stratification. Habitat descriptions in first-level analyses were based on dominant species of vegetation. Habitat descriptions in second-level analyses were based on dominant species of vegetation and overstory canopy cover. Habitat descriptions in third-...

  7. Habitats, activities, and signs

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh; Brynskov, Martin

    2004-01-01

    Digital habitats is a framework for designing and modeling environments for activities that involve mobile and embedded computing systems. This paper 1) introduces the basic concepts of the framework, i.e. activity, thematic role, and the three ‘dimensions’ of a habitat: physical, informational, ...

  8. Advanced Plant Habitat (APH)

    Science.gov (United States)

    Richards, Stephanie E. (Compiler); Levine, Howard G.; Reed, David W.

    2016-01-01

    The Advanced Plant Habitat (APH) hardware will be a large growth volume plant habitat, capable of hosting multigenerational studies, in which environmental variables (e.g., temperature, relative humidity, carbon dioxide level light intensity and spectral quality) can be tracked and controlled in support of whole plant physiological testing and Bio-regenerative Life Support System investigations.

  9. Wildlife habitat considerations

    Science.gov (United States)

    Helen Y. Smith

    2000-01-01

    Fire, insects, disease, harvesting, and precommercial thinning all create mosaics on Northern Rocky Mountain landscapes. These mosaics are important for faunal habitat. Consequently, changes such as created openings or an increase in heavily stocked areas affect the water, cover, and food of forest habitats. The “no action” alternative in ecosystem management of low...

  10. Methylmercury enters an aquatic food web through acidophilic microbial mats in Yellowstone National Park, Wyoming.

    Science.gov (United States)

    Boyd, Eric S; King, Susan; Tomberlin, Jeffery K; Nordstrom, D Kirk; Krabbenhoft, David P; Barkay, Tamar; Geesey, Gill G

    2009-04-01

    Microbial mats are a visible and abundant life form inhabiting the extreme environments in Yellowstone National Park (YNP), WY, USA. Little is known of their role in food webs that exist in the Park's geothermal habitats. Eukaryotic green algae associated with a phototrophic green/purple Zygogonium microbial mat community that inhabits low-temperature regions of acidic (pH approximately 3.0) thermal springs were found to serve as a food source for stratiomyid (Diptera: Stratiomyidae) larvae. Mercury in spring source water was taken up and concentrated by the mat biomass. Monomethylmercury compounds (MeHg(+)), while undetectable or near the detection limit (0.025 ng l(-1)) in the source water of the springs, was present at concentrations of 4-7 ng g(-1) dry weight of mat biomass. Detection of MeHg(+) in tracheal tissue of larvae grazing the mat suggests that MeHg(+) enters this geothermal food web through the phototrophic microbial mat community. The concentration of MeHg(+) was two to five times higher in larval tissue than mat biomass indicating MeHg(+) biomagnification occurred between primary producer and primary consumer trophic levels. The Zygogonium mat community and stratiomyid larvae may also play a role in the transfer of MeHg(+) to species in the food web whose range extends beyond a particular geothermal feature of YNP.

  11. Towards a microbial thermoelectric cell.

    Directory of Open Access Journals (Sweden)

    Raúl Rodríguez-Barreiro

    Full Text Available Microbial growth is an exothermic process. Biotechnological industries produce large amounts of heat, usually considered an undesirable by-product. In this work, we report the construction and characterization of the first microbial thermoelectric cell (MTC, in which the metabolic heat produced by a thermally insulated microbial culture is partially converted into electricity through a thermoelectric device optimized for low ΔT values. A temperature of 41°C and net electric voltage of around 250-600 mV was achieved with 1.7 L baker's yeast culture. This is the first time microbial metabolic energy has been converted into electricity with an ad hoc thermoelectric device. These results might contribute towards developing a novel strategy to harvest excess heat in the biotechnology industry, in processes such as ethanol fermentation, auto thermal aerobic digestion (ATAD or bioremediation, which could be coupled with MTCs in a single unit to produce electricity as a valuable by-product of the primary biotechnological product. Additionally, we propose that small portable MTCs could be conceived and inoculated with suitable thermophilic of hyperthermophilic starter cultures and used for powering small electric devices.

  12. Habitat Blocks and Wildlife Corridors

    Data.gov (United States)

    Vermont Center for Geographic Information — Habitat blocks are areas of contiguous forest and other natural habitats that are unfragmented by roads, development, or agriculture. Vermonts habitat blocks are...

  13. Microbial life in ridge flank crustal fluids.

    Science.gov (United States)

    Huber, Julie A; Johnson, H Paul; Butterfield, David A; Baross, John A

    2006-01-01

    To determine the microbial community diversity within old oceanic crust, a novel sampling strategy was used to collect crustal fluids at Baby Bare Seamount, a 3.5 Ma old outcrop located in the north-east Pacific Ocean on the eastern flank of the Juan de Fuca Ridge. Stainless steel probes were driven directly into the igneous ocean crust to obtain samples of ridge flank crustal fluids. Genetic signatures and enrichment cultures of microorganisms demonstrate that these crustal fluids host a microbial community composed of species indigenous to the subseafloor, including anaerobic thermophiles, and species from other deep-sea habitats, such as seawater and sediments. Evidence using molecular techniques indicates the presence of a relatively small but active microbial population, dominated by bacteria. The microbial community diversity found in the crustal fluids may indicate habitat variability in old oceanic crust, with inputs of nutrients from seawater, sediment pore-water fluids and possibly hydrothermal sources. This report further supports the presence of an indigenous microbial community in ridge flank crustal fluids and advances our understanding of the potential physiological and phylogenetic diversity of this community.

  14. Microbial biodiversity in glacier-fed streams.

    Science.gov (United States)

    Wilhelm, Linda; Singer, Gabriel A; Fasching, Christina; Battin, Tom J; Besemer, Katharina

    2013-08-01

    While glaciers become increasingly recognised as a habitat for diverse and active microbial communities, effects of their climate change-induced retreat on the microbial ecology of glacier-fed streams remain elusive. Understanding the effect of climate change on microorganisms in these ecosystems is crucial given that microbial biofilms control numerous stream ecosystem processes with potential implications for downstream biodiversity and biogeochemistry. Here, using a space-for-time substitution approach across 26 Alpine glaciers, we show how microbial community composition and diversity, based on 454-pyrosequencing of the 16S rRNA gene, in biofilms of glacier-fed streams may change as glaciers recede. Variations in streamwater geochemistry correlated with biofilm community composition, even at the phylum level. The most dominant phyla detected in glacial habitats were Proteobacteria, Bacteroidetes, Actinobacteria and Cyanobacteria/chloroplasts. Microorganisms from ice had the lowest α diversity and contributed marginally to biofilm and streamwater community composition. Rather, streamwater apparently collected microorganisms from various glacial and non-glacial sources forming the upstream metacommunity, thereby achieving the highest α diversity. Biofilms in the glacier-fed streams had intermediate α diversity and species sorting by local environmental conditions likely shaped their community composition. α diversity of streamwater and biofilm communities decreased with elevation, possibly reflecting less diverse sources of microorganisms upstream in the catchment. In contrast, β diversity of biofilms decreased with increasing streamwater temperature, suggesting that glacier retreat may contribute to the homogenisation of microbial communities among glacier-fed streams.

  15. Microbial lipid remnants within sulfide chimneys reveal organic matter transport in seafloor hydrothermal systems

    Science.gov (United States)

    Reeves, E.; Goldenstein, N. I.; Yoshinaga, M. Y.; Pjevac, P.; Bach, W.; Hinrichs, K.

    2013-12-01

    Several investigations have detected enigmatic evidence for microbial life in high-temperature (>150°C) interiors of hydrothermal vent ';chimney' structures - habitats much hotter than the known temperature limit of life. It is unclear whether these findings reflect fluid ingress after collection, cross-contamination with exterior microbial biomass, or genuine natural phenomena. While the abundant microbial biomass on the exteriors of vent edifices has been more commonly characterized, the origin of biomolecules inside these structures is poorly understood. In this study, we used a novel ';clean' sampling approach to investigate these interior regions in both a moderate temperature ';diffuser' and an inactive ';smoker' chimney structure from the Manus Basin, and use microbial DNA- and detailed lipid-based characterization to elucidate provenances. Mineralogical analysis using scanning-electron- and reflected-light-microscopy suggests vent fluid temperatures of up to ~200°C for the diffuser and >200°C during previous venting of the inactive chimney. No DNA could be amplified from any interior samples and cell membrane intact polar lipids were only recovered from the outer surfaces of the structures, precluding the possibility of active microbial communities in interior regions of either. Free fatty acids from bacteria, however, were abundant in the inactive chimney, including the previously high temperature interior, suggesting possible microbial colonization of the interior or inward transport of biomass during waning of fluid flow. Free fatty acids were not detected in the interior of the active diffuser chimney, consistent with uninhabitable temperatures for microbes and outward fluid flow. In contrast to fatty acids, archaeal core diether and tetraether lipid remnants with distinctive provenances were present in interior and exterior samples from both structures. Principal component analysis (PCA) of these mixtures reveals gradients in their distribution

  16. Thermoregulation and temperature relations of alligators and other large ectotherms inhabiting thermally stressed habitats. Annual progress report, 1 July 1976--30 September 1977. [Ecology of Par Pond, Savannah River Reservation

    Energy Technology Data Exchange (ETDEWEB)

    Spotila, J.R.

    1977-06-01

    Progress is reported on studies of the biophysical and thermal relationships between large ectotherms and their aquatic environment. Data are reported from laboratory and field studies on alligators, turtles, and fish. Mathematical models of the effect of body size and physical characteristics on temperature regulation of ectotherms and of thermal stress in aquatic organisms were developed. Results are included of field studies on the physiological and behavioral adjustments of turtles in response to changes in water temperature produced by thermal effluents in PAR Pond at the Savannah River Ecology Laboratory (SREL).

  17. Microbial Ecosystems, Protection of

    NARCIS (Netherlands)

    Bodelier, P.L.E.; Nelson, K.E.

    2014-01-01

    Synonyms Conservation of microbial diversity and ecosystem functions provided by microbes; Preservation of microbial diversity and ecosystem functions provided by microbes Definition The use, management, and conservation of ecosystems in order to preserve microbial diversity and functioning.

  18. Local environmental conditions shape generalist but not specialist components of microbial metacommunities in the Baltic Sea

    DEFF Research Database (Denmark)

    Lindh, Markus V.; Sjöstedt, Johanna; Casini, Michele

    2016-01-01

    Bacteroidetes and Verrucomicrobia were assembled by SS and mass effect. Concomitantly, Gammaproteobacteria were assembled by the neutral model and patch dynamics. Temporal variation in habitat filtering and dispersal highlights the impact of seasonally driven reorganization of microbial communities. Typically...

  19. Size and structure of microbial, fungal and nematode communities along an Antarctic environmental gradient.

    NARCIS (Netherlands)

    Yergeau, E.; Bokhorst, S.F.; Huiskes, A.H.L.; Boschker, H.T.S.; Aerts, R.; Kowalchuk, G.A.

    2007-01-01

    The unusually harsh environmental conditions of terrestrial Antarctic habitats result in ecosystems with simplified trophic structures, where microbial processes are especially dominant as drivers of soil-borne nutrient cycling. We examined soil-borne Antarctic communities (bacteria, fungi and

  20. Microbial metropolis.

    Science.gov (United States)

    Wimpenny, Julian

    2009-01-01

    Microorganisms can form tightly knit communities such as biofilms. Many others include marine snow, anaerobic digester granules, the ginger beer plant and bacterial colonies. This chapter is devoted to a survey of the main properties of these communities, with an emphasis on biofilms. We start with attachment to surfaces and the nature of adhesion. The growing community then forms within a matrix, generally of organic macromolecules. Inevitably the environment within such a matrix is different from that outside. Organisms respond by forming crowd-detection and response units; these quorum sensing systems act as switches between planktonic life and the dramatically altered conditions found inside microbial aggregates. The community then matures and changes and may even fail and disappear. Antimicrobial resistance is discussed as an example of multicellular behavior. The multicellular lifestyle has been modeled mathematically and responded to powerful molecular biological techniques. Latterly, microbial systems have been used as models for fundamental evolutionary processes, mostly because of their high rates of reproduction and the ease of genetic manipulation. The life of most microbes is a duality between the yin of the community and the yang of planktonic existence. Sadly far less research has been devoted to adaptation to free-living forms than in the opposite direction. Copyright © 2009 Elsevier Ltd. All rights reserved.

  1. Critical Habitat Designations

    Data.gov (United States)

    Department of Homeland Security — The Endangered Species Act (ESA) requires the Federal government to designate 'critical habitat' for any species it lists under the ESA. This dataset combines both...

  2. Green Turtle Critical Habitat

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  3. Majuro_Benthic_Habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Benthic habitat maps of the nearshore marine environment of Majuro, Republic of the Marshall Islands were created by visual interpretation of remotely sensed...

  4. VT Wildlife Linkage Habitat

    Data.gov (United States)

    Vermont Center for Geographic Information — (Link to Metadata) The Wildlife Linkage Habitat Analysis uses landscape scale data to identify or predict the location of potentially significant wildlife linkage...

  5. Habitat Mapping Camera (HABCAM)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This dataset entails imagery collected using the HabCam towed underwater vehicle and annotated data on objects or habitats in the images and notes on image...

  6. Johnsons Seagrass Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Johnson's Seagrass as designated by Federal Register Vol. 65, No. 66, Wednesday, April 5, 2000, Rules and Regulations.

  7. Designated Critical Habitat

    Data.gov (United States)

    Kansas Data Access and Support Center — Critical habitats include those areas documented as currently supporting self-sustaining populations of any threatened or endangered species of wildlife as well as...

  8. Right Whale Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for Right Whale as designated by Federal Register Vol. 59, No. 28805, May 19, 1993, Rules and Regulations.

  9. Smalltooth Sawfish Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for smalltooth sawfish (Pristis pectinatat) as designated by 74 FR 45353, September 2, 2009, Rules and Regulations.

  10. Green Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for green turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations.

  11. Soil thermal conductivity, organic matter, activity and microbial biomass in crops systems of passion fruit in Toro, Valle del Cauca, Colombia Conductividad térmica del suelo, materia orgánica, actividad y biomasa microbianas en sistemas de cultivo de maracuyá en Toro, Valle del Cauca

    Directory of Open Access Journals (Sweden)

    Pérez Jesús

    2007-03-01

    Full Text Available The study evaluated the relationship among soil thermal conductivity (λ organic matter, activity and microbial biomass. In three systems of passion fruit crop (ecological, transitional and conventional in the municipality of Toro, Valle del Cauca, Colombia. In samples taken at random in two depths (0-15 and 15-30 cm, biological properties microbial activity (C-CO2; microbial biomass (microbial C - fumigation, extraction - and physical and chemical properties (organic matter, pH, humidity, texture, apparent density, porosity (traditional methods and thermal conductivity of the soil (electrothermal method were measured. The results were analyzed program SAS through models of lineal regression, LSD and Duncan. There were highly significant differences in organic matter, activity and microbial biomass and thermal conductivity of the soil at both depths.The most notorious among ecological and conventional crops. High correlations of direct proportionality were calculated among thermal conductivity of the soil (λ and soil organic matter, for the three crop systems. The ecological crop increased these properties and activity and microbial biomass. Key words: Passiflora edulis Sims var flavicarpa, crop systems, soil thermal conductivity, organic matter, activity and microbial biomass.El estudio evaluó la relación entre la conductividad térmica del suelo (λ, la materia orgánica, la actividad y la biomasa microbianas. En tres sistemas de cultivo de maracuyá (agroecológico, transición y convencional en el municipio de Toro (Valle del Cauca, en nueve puntos por manejo se tomaron muestras al azar a dos profundidades (0-15 y 15-30 cm y se midieron propiedades biológicas: (actividad microbiana (C-CO2; biomasa microbiana (C microbiano –fumigación, extracción– y propiedades físicas y químicas (materia orgánica, pH, humedad, textura, densidad aparente, porosidad (métodos tradicionales y conductividad térmica del suelo (m

  12. Landscape habitat suitability index software

    Science.gov (United States)

    William D. Dijak; Chadwick D. Rittenhouse; Michael A. Larson; Frank R. III Thompson; Joshua J. Millspaugh

    2007-01-01

    Habitat suitability index (HSI) models are traditionally used to evaluate habitat quality for wildlife at a local scale. Rarely have such models incorporated spatial relationships of habitat components. We introduce Landscape HSImodels, a new Microsoft Windowst (Microsoft, Redmond, WA)-based program that incorporates local habitat as well as landscape-scale attributes...

  13. Effect of leaf type and pesticide exposure on abundance of bacterial taxa in mosquito larval habitats.

    Directory of Open Access Journals (Sweden)

    Ephantus J Muturi

    Full Text Available Lentic freshwater systems including those inhabited by aquatic stages of mosquitoes derive most of their carbon inputs from terrestrial organic matter mainly leaf litter. The leaf litter is colonized by microbial communities that provide the resource base for mosquito larvae. While the microbial biomass associated with different leaf species in container aquatic habitats is well documented, the taxonomic composition of these microbes and their response to common environmental stressors is poorly understood. We used indoor aquatic microcosms to determine the abundances of major taxonomic groups of bacteria in leaf litters from seven plant species and their responses to low concentrations of four pesticides with different modes of action on the target organisms; permethrin, malathion, atrazine and glyphosate. We tested the hypotheses that leaf species support different quantities of major taxonomic groups of bacteria and that exposure to pesticides at environmentally relevant concentrations alters bacterial abundance and community structure in mosquito larval habitats. We found support for both hypotheses suggesting that leaf litter identity and chemical contamination may alter the quality and quantity of mosquito food base (microbial communities in larval habitats. The effect of pesticides on microbial communities varied significantly among leaf types, suggesting that the impact of pesticides on natural microbial communities may be highly complex and difficult to predict. Collectively, these findings demonstrate the potential for detritus composition within mosquito larval habitats and exposure to pesticides to influence the quality of mosquito larval habitats.

  14. Effect of leaf type and pesticide exposure on abundance of bacterial taxa in mosquito larval habitats.

    Science.gov (United States)

    Muturi, Ephantus J; Orindi, Benedict O; Kim, Chang-Hyun

    2013-01-01

    Lentic freshwater systems including those inhabited by aquatic stages of mosquitoes derive most of their carbon inputs from terrestrial organic matter mainly leaf litter. The leaf litter is colonized by microbial communities that provide the resource base for mosquito larvae. While the microbial biomass associated with different leaf species in container aquatic habitats is well documented, the taxonomic composition of these microbes and their response to common environmental stressors is poorly understood. We used indoor aquatic microcosms to determine the abundances of major taxonomic groups of bacteria in leaf litters from seven plant species and their responses to low concentrations of four pesticides with different modes of action on the target organisms; permethrin, malathion, atrazine and glyphosate. We tested the hypotheses that leaf species support different quantities of major taxonomic groups of bacteria and that exposure to pesticides at environmentally relevant concentrations alters bacterial abundance and community structure in mosquito larval habitats. We found support for both hypotheses suggesting that leaf litter identity and chemical contamination may alter the quality and quantity of mosquito food base (microbial communities) in larval habitats. The effect of pesticides on microbial communities varied significantly among leaf types, suggesting that the impact of pesticides on natural microbial communities may be highly complex and difficult to predict. Collectively, these findings demonstrate the potential for detritus composition within mosquito larval habitats and exposure to pesticides to influence the quality of mosquito larval habitats.

  15. Microbial lifestyles that enable survival in lithifying habitats

    DEFF Research Database (Denmark)

    Tamez-Hidalgo, Paulina

    2010-01-01

    The precipitation of carbonates in the travertine forming Narrow Gauge hot spring in Yellowstone National Park occurs at a rapid rate, whereby microorganisms that colonize the ponds and apron facies are required to overcome lithification. CO2-fixation by autotrophic microorganisms in this cation-...

  16. Influences of space, soil, nematodes and plants on microbial community composition of chalk grassland soils

    NARCIS (Netherlands)

    Yergeau, E.; Bezemer, T.M.; Hedlund, K.; Mortimer, S.R.; Kowalchuk, G.A.; Van der Putten, W.H.

    2010-01-01

    Microbial communities respond to a variety of environmental factors related to resources (e.g. plant and soil organic matter), habitat (e.g. soil characteristics) and predation (e.g. nematodes, protozoa and viruses). However, the relative contribution of these factors on microbial community

  17. Microbial fuel cells: Running on gas

    Science.gov (United States)

    Ren, Zhiyong Jason

    2017-06-01

    Methane is an abundant energy source that is used for power generation in thermal power plants via combustion, but direct conversion to electricity in fuel cells remains challenging. Now, a microbial fuel cell is demonstrated to efficiently convert methane directly to current by careful selection of a consortium of microorganisms.

  18. Microbial mat ecosystems: Structure types, functional diversity, and biotechnological application

    Directory of Open Access Journals (Sweden)

    Cristina M. Prieto-Barajas

    2018-01-01

    Full Text Available Microbial mats are horizontally stratified microbial communities, exhibiting a structure defined by physiochemical gradients, which models microbial diversity, physiological activities, and their dynamics as a whole system. These ecosystems are commonly associated with aquatic habitats, including hot springs, hypersaline ponds, and intertidal coastal zones and oligotrophic environments, all of them harbour phototrophic mats and other environments such as acidic hot springs or acid mine drainage harbour non-photosynthetic mats. This review analyses the complex structure, diversity, and interactions between the microorganisms that form the framework of different types of microbial mats located around the globe. Furthermore, the many tools that allow studying microbial mats in depth and their potential biotechnological applications are discussed.

  19. Saproxylic Hemiptera Habitat Associations

    Science.gov (United States)

    Michael D. Ulyshen; James L. Hanula; Robert L. Blinn; Gene. Kritsky

    2012-01-01

    Understanding the habitat requirements of organisms associated with dead wood is important in order to conserve them in managed forests. Unfortunately, many of the less diverse saproxylic taxa, including Hemiptera, remain largely unstudied. An effort to rear insects from dead wood taken from two forest types (an upland pine-dominated and a bottomland mixed hardwood),...

  20. Wildlife habitat fragmentation.

    Science.gov (United States)

    John. Lehmkuhl

    2005-01-01

    A primary issue in forest wildlife management is habitat fragmentation and its effects on viability, which is the "bottom line" for plant and animal species of conservation concern. Population viability is the likelihood that a population will be able to maintain itself (remain viable) over a long period of time-usually 100 years or more. Though it is true...

  1. Earth is a Marine Habitat. Habitat Conservation Program.

    Science.gov (United States)

    National Oceanic and Atmospheric Administration (DOC), Rockville, MD.

    This brochure is intended to educate the public about the need to conserve and preserve the earth's environment (man's habitat). It contains an introduction to the ocean world and threats to coastal habitat. Photos and narrative revolve around the theme "Earth is a Marine Habitat." Sections include: "The Web of…

  2. Microbial diversity in soil: selection of the microbial populations by plant and soil type and implementations for disease suppressivenss.

    NARCIS (Netherlands)

    Garbeva, P.; Veen, van J.A.; Elsas, van J.D.

    2004-01-01

    An increasing interest has emerged with respect to the importance of microbial diversity in soil habitats. The extent of the diversity of microorganisms in soil is seen to be critical to the maintenance of soil health and quality, as a wide range of microorganisms is involved in important soil

  3. Microbial diversity in soil : Selection of microbial populations by plant and soil type and implications for disease suppressiveness

    NARCIS (Netherlands)

    Garbeva, P; van Veen, JA; van Elsas, JD

    2004-01-01

    An increasing interest has emerged with respect to the importance of microbial diversity in soil habitats. The extent of the diversity of microorganisms in soil is seen to be critical to the maintenance of soil health and quality, as a wide range of microorganisms is involved in important soil

  4. Microbial Siderophores

    Science.gov (United States)

    Budzikiewicz, Herbert

    Iron is of great importance for many metabolic processes since the redox potential between its two valence states Fe2+ and Fe3+ lies within the range of physiological processes. Actually, iron is not a rare element, it is fourth in abundance in the earth crust, but it is not readily available for microorganisms. In the soil ferric oxide hydrates are formed at pH values around seven and the concentration of free Fe3+ is at best 10-17 mol/dm3 while about 10-6 mol/dm3 would be needed. In living organisms iron is usually strongly bound to peptidic substances such as transferrins. To increase the supply of soluble iron microorganisms other than those living in an acidic habitat may circumvent the problem by reduction of Fe3+ to Fe2+ (182), which seems to be of major importance for marine phytoplankton (151); see also amphiphilic marine bacteria (Sect.2.8) and Fe2+ binding ligands (Sect. 7) below. An important alternative is the production of Fe3+ chelating compounds, so-called siderophores. Siderophores are secondary metabolites with masses below 2,000 Da and a high affinity to Fe3+. Small iron-siderophore complexes can enter the cell via unspecific porins, larger ones need a transport system that recognizes the ferri-siderophore at the cell surface. In the cell, iron is released mostly by reduction to the less strongly bound Fe2+ state (137), and the free siderophore is re-exported ("shuttle mechanism"); for a modified shuttle system see pyoverdins (Sect. 2.1) and amonabactins (Sect. 2.7). Rarely the siderophore is degraded in the periplasmatic space as, e.g. enterobactin (Sect. 2.7). Alternatively Fe3+ is transferred at the cell surface from the ferri-siderophore to a trans-membrane transport system ("taxi mechanism"). A probably archaic and unspecific variety of the taxi mechanism comprises the reduction of Fe3+ at the cell surface (see ferrichrome A, Sect. 2.6 (99, 105)). The terms "shuttle" and "taxi mechanism" were coined by Raymond and Carrano (296).

  5. NEPR Benthic Habitat Map 2015

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This benthic habitat map was created from a semi-automated habitat mapping process, using a combination of bathymetry, satellite imagery, aerial imagery and...

  6. NORTHWOODS Wildlife Habitat Data Base

    Science.gov (United States)

    Mark D. Nelson; Janine M. Benyus; Richard R. Buech

    1992-01-01

    Wildlife habitat data from seven Great Lakes National Forests were combined into a wildlife-habitat matrix named NORTHWOODS. Several electronic file formats of NORTHWOODS data base and documentation are available on floppy disks for microcomputers.

  7. Carpinteria Salt Marsh Habitat Polygons

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — We identified five common habitat types in Carpinteria Salt Marsh: channels, pans (flats), marsh, salt flat and upland. We then drew polygons around each habitat...

  8. Microbial community response to hydration-desiccation cycles in desert soil.

    Science.gov (United States)

    Šťovíček, Adam; Kim, Minsu; Or, Dani; Gillor, Osnat

    2017-04-06

    Life in desert soil is marked by episodic pulses of water and nutrients followed by long periods of drought. While the desert flora and fauna flourish after rainfall the response of soil microorganisms remains unclear and understudied. We provide the first systematic study of the role of soil aqueous habitat dynamics in shaping microbial community composition and diversity. Detailed monitoring of natural microbial communities after a rainfall event revealed a remarkable decrease in diversity and a significant transition in community composition that were gradually restored to pre-rainfall values during soil desiccation. Modelling results suggest a critical role for the fragmented aqueous habitat in maintaining microbial diversity under dry soil conditions and diversity loss with wetting events that increase connectivity among habitats. This interdisciplinary study provides new insights into wetting and drying processes that promote and restore the unparalleled microbial diversity found in soil.

  9. Environmental Monitoring as Part of Life Support for the Crew Habitat for Lunar and Mars Missions

    Science.gov (United States)

    Jan, Darrell L.

    2010-01-01

    Like other crewed space missions, future missions to the moon and Mars will have requirements for monitoring the chemical and microbial status of the crew habitat. Monitoring the crew habitat becomes more critical in such long term missions. This paper will describe the state of technology development for environmental monitoring of lunar lander and lunar outpost missions, and the state of plans for future missions.

  10. Microbial community changes along the active seepage site of one cold seep in the Red Sea

    Directory of Open Access Journals (Sweden)

    Huiluo eCao

    2015-07-01

    Full Text Available The active seepage of the marine cold seeps could be a critical process for the exchange of energy between the submerged geosphere and the sea floor environment through organic-rich fluids, potentially even affecting surrounding microbial habitats. However, few studies have investigated the associated microbial community changes. In the present study, 16S rRNA genes were pyrosequenced to decipher changes in the microbial communities from the Thuwal seepage point in the Red Sea to nearby marine sediments in the brine pool, normal marine sediments and water, and benthic microbial mats. An unexpected number of reads from unclassified groups were detected in these habitats; however, the ecological functions of these groups remain unresolved. Furthermore, ammonia-oxidizing archaeal community structures were investigated using the ammonia monooxygenase subunit A (amoA gene. Analysis of amoA showed that planktonic marine habitats, including seeps and marine water, hosted archaeal ammonia oxidizers that differed from those in microbial mats and marine sediments, suggesting modifications of the ammonia oxidizing archaeal communities along the environmental gradient from active seepage sites to peripheral areas. Changes in the microbial community structure of ammonia oxidizing archaea in different habitats (water versus sediment potentially correlated with changes in salinity and oxygen concentrations. Overall, the present results revealed for the first time unanticipated novel microbial groups and changes in the ammonia-oxidizing archaea in response to environmental gradients near the active seepages of a cold seep.

  11. Microbial community changes along the active seepage site of one cold seep in the Red Sea.

    KAUST Repository

    Cao, Huiluo

    2015-07-21

    The active seepage of the marine cold seeps could be a critical process for the exchange of energy between the submerged geosphere and the sea floor environment through organic-rich fluids, potentially even affecting surrounding microbial habitats. However, few studies have investigated the associated microbial community changes. In the present study, 16S rRNA genes were pyrosequenced to decipher changes in the microbial communities from the Thuwal seepage point in the Red Sea to nearby marine sediments in the brine pool, normal marine sediments and water, and benthic microbial mats. An unexpected number of reads from unclassified groups were detected in these habitats; however, the ecological functions of these groups remain unresolved. Furthermore, ammonia-oxidizing archaeal community structures were investigated using the ammonia monooxygenase subunit A (amoA) gene. Analysis of amoA showed that planktonic marine habitats, including seeps and marine water, hosted archaeal ammonia oxidizers that differed from those in microbial mats and marine sediments, suggesting modifications of the ammonia oxidizing archaeal (AOA) communities along the environmental gradient from active seepage sites to peripheral areas. Changes in the microbial community structure of AOA in different habitats (water vs. sediment) potentially correlated with changes in salinity and oxygen concentrations. Overall, the present results revealed for the first time unanticipated novel microbial groups and changes in the ammonia-oxidizing archaea in response to environmental gradients near the active seepages of a cold seep.

  12. Sound solutions for habitat monitoring

    Science.gov (United States)

    Mary M. Rowland; Lowell H. Suring; Christina D. Vojta

    2015-01-01

    For agencies and organizations to effectively manage wildlife, knowledge about the status and trend of wildlife habitat is critical. Traditional wildlife monitoring, however, has focused on populations rather than habitat, because ultimately population status drives long-term species viability. Still, habitat loss has contributed to the decline of nearly all at-risk...

  13. Habitat Use Database - Groundfish Essential Fish Habitat (EFH) Habitat Use Database (HUD)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Habitat Use Database (HUD) was specifically designed to address the need for habitat-use analyses in support of groundfish EFH, HAPCs, and fishing and nonfishing...

  14. Microbial conversions of terpenoids

    OpenAIRE

    Parshikov, Igor A

    2015-01-01

    The monograph describes examples of the application of microbial technology for obtaining of derivatives of terpenoids. Obtaining new derivatives of terpenoids, including artemisinin derivatives with increased antimalarial activity, is an important goal of research in microbial biotechnology and medicinal chemistry.

  15. Habitats of Life

    Science.gov (United States)

    Dirk, Schulze-Makuch; Irwin, Louis N.

    There are four principal habitats in which life may exist - the surface of a planetary body, its subsurface, its atmosphere and space. From our own experience we know that life does exist on the surface of a planet, in its subsurface, and transiently at least in the atmosphere. Where it is present, it exists in a surprising diversity and in a variety of microhabitats, from deep caverns (Hose et al. 2000, Melim et al. 2001) to hydrothermal fluids and hot springs of various chemistries (Jannasch 1995, Rzonca and Schulze-Makuch 2002), to the frozen deserts of Antarctica (Friedmann 1982, Sun and Friedmann 1999). In this chapter we will elaborate on the principal habitats, the constraints they impose on life, and the possibilities they provide.

  16. Habitat monitoring needs for Arapaho NWR

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This document is the refuge's ideas on what level of monitoring is needed for each habitat objective. Habitat objectives include riparian habitat, wetland habitat,...

  17. Measuring acoustic habitats.

    Science.gov (United States)

    Merchant, Nathan D; Fristrup, Kurt M; Johnson, Mark P; Tyack, Peter L; Witt, Matthew J; Blondel, Philippe; Parks, Susan E

    2015-03-01

    1. Many organisms depend on sound for communication, predator/prey detection and navigation. The acoustic environment can therefore play an important role in ecosystem dynamics and evolution. A growing number of studies are documenting acoustic habitats and their influences on animal development, behaviour, physiology and spatial ecology, which has led to increasing demand for passive acoustic monitoring (PAM) expertise in the life sciences. However, as yet, there has been no synthesis of data processing methods for acoustic habitat monitoring, which presents an unnecessary obstacle to would-be PAM analysts. 2. Here, we review the signal processing techniques needed to produce calibrated measurements of terrestrial and aquatic acoustic habitats. We include a supplemental tutorial and template computer codes in matlab and r, which give detailed guidance on how to produce calibrated spectrograms and statistical analyses of sound levels. Key metrics and terminology for the characterisation of biotic, abiotic and anthropogenic sound are covered, and their application to relevant monitoring scenarios is illustrated through example data sets. To inform study design and hardware selection, we also include an up-to-date overview of terrestrial and aquatic PAM instruments. 3. Monitoring of acoustic habitats at large spatiotemporal scales is becoming possible through recent advances in PAM technology. This will enhance our understanding of the role of sound in the spatial ecology of acoustically sensitive species and inform spatial planning to mitigate the rising influence of anthropogenic noise in these ecosystems. As we demonstrate in this work, progress in these areas will depend upon the application of consistent and appropriate PAM methodologies.

  18. A Multi-Environment Thermal Control System With Freeze-Tolerant Radiator Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Future space exploration missions require advanced thermal control systems (TCS) to dissipate heat from spacecraft, rovers, or habitats to external environments. We...

  19. Molecular microbial ecology manual

    NARCIS (Netherlands)

    Kowalchuk, G.A.; Bruijn, de F.J.; Head, I.M.; Akkermans, A.D.L.

    2004-01-01

    The field of microbial ecology has been revolutionized in the past two decades by the introduction of molecular methods into the toolbox of the microbial ecologist. This molecular arsenal has helped to unveil the enormity of microbial diversity across the breadth of the earth's ecosystems, and has

  20. Manipulatiaon of Biofilm Microbial Ecology

    Energy Technology Data Exchange (ETDEWEB)

    Burkhalter, R.; Macnaughton, S.J.; Palmer, R.J.; Smith, C.A.; Whitaker, K.W.; White, D.C.; Zinn, M.; kirkegaard, R.

    1998-08-09

    The Biofilm mode of growth provides such significant advantages to the members of the consortium that most organisms in important habitats are found in biofilms. The study of factors that allow manipulation of biofilm microbes in the biofilm growth state requires that reproducible biofilms by generated. The most effective monitoring of biofilm formation, succession and desquamation is with on-line monitoring of microbial biofilms with flowcell for direct observation. The biofilm growth state incorporates a second important factor, the heterogeneity in the distribution in time and space of the component members of the biofilm consortium. This heterogeneity is reflected not only in the cellular distribution but in the metabolic activity within a population of cells. Activity and cellular distribution can be mapped in four dimensions with confocal microscopy, and function can be ascertained by genetically manipulated reporter functions for specific genes or by vital stains. The methodology for understanding the microbial ecology of biofilms is now much more readily available and the capacity to manipulate biofilms is becoming an important feature of biotechnology.

  1. Manipulation of Biofilm Microbial Ecology

    Energy Technology Data Exchange (ETDEWEB)

    White, D.C.; Palmer, R.J., Jr.; Zinn, M.; Smith, C.A.; Burkhalter, R.; Macnaughton, S.J.; Whitaker, K.W.; Kirkegaard, R.D.

    1998-08-15

    The biofilm mode of growth provides such significant advantages to the members of the consortium that most organisms in important habitats are found in biofilms. The study of factors that allow manipulation of biofilm microbes in the biofilm growth state requires that reproducible biofilms be generated. The most effective monitoring of biofilm formation, succession and desaturation is with on-line monitoring of microbial biofilms with flowcell for direct observation. The biofilm growth state incorporates a second important factor, the heterogeneity in distribution in time and space of the component members of the biofilm consortium. This heterogeneity is reflected not only in the cellular distribution but in the metabolic activity within a population of cells. Activity and cellular distribution can be mapped in four dimensions with confocal microscopy, and function can be ascertained by genetically manipulated reporter functions for specific genes or by vital stains. The methodology for understanding the microbial ecology of biofilms is now much more readily available and the capacity to manipulate biofilms is becoming an important feature of biotechnology.

  2. Plant Habitat (PH)

    Science.gov (United States)

    Onate, Bryan

    2016-01-01

    The International Space Station (ISS) will soon have a platform for conducting fundamental research of Large Plants. Plant Habitat (PH) is designed to be a fully controllable environment for high-quality plant physiological research. PH will control light quality, level, and timing, temperature, CO2, relative humidity, and irrigation, while scrubbing ethylene. Additional capabilities include leaf temperature and root zone moisture and oxygen sensing. The light cap will have red (630 nm), blue (450 nm), green (525 nm), far red (730 nm) and broad spectrum white LEDs. There will be several internal cameras (visible and IR) to monitor and record plant growth and operations.

  3. Potential sources of microbial colonizers in an initial soil ecosystem after retreat of an alpine glacier.

    Science.gov (United States)

    Rime, Thomas; Hartmann, Martin; Frey, Beat

    2016-07-01

    Rapid disintegration of alpine glaciers has led to the formation of new terrain consisting of mineral debris colonized by microorganisms. Despite the importance of microbial pioneers in triggering the formation of terrestrial ecosystems, their sources (endogenous versus exogenous) and identities remain elusive. We used 454-pyrosequencing to characterize the bacterial and fungal communities in endogenous glacier habitats (ice, sub-, supraglacial sediments and glacier stream leaving the glacier forefront) and in atmospheric deposition (snow, rain and aeolian dust). We compared these microbial communities with those occurring in recently deglaciated barren soils before and after snow melt (snow-covered soil and barren soil). Atmospheric bacteria and fungi were dominated by plant-epiphytic organisms and differed from endogenous glacier habitats and soils indicating that atmospheric input of microorganisms is not a major source of microbial pioneers in newly formed soils. We found, however, that bacterial communities in newly exposed soils resembled those of endogenous habitats, which suggests that bacterial pioneers originating from sub- and supraglacial sediments contributed to the colonization of newly exposed soils. Conversely, fungal communities differed between habitats suggesting a lower dispersal capability than bacteria. Yeasts putatively adapted to cold habitats characteristic of snow and supraglacial sediments were similar, despite the fact that these habitats were not spatially connected. These findings suggest that environmental filtering selects particular fungi in cold habitats. Atmospheric deposition provided important sources of dissolved organic C, nitrate and ammonium. Overall, microbial colonizers triggering soil development in alpine environments mainly originate from endogenous glacier habitats, whereas atmospheric deposition contributes to the establishment of microbial communities by providing sources of C and N.

  4. 78 FR 63100 - Endangered and Threatened Wildlife and Plants; Revised Critical Habitat for the Comal Springs...

    Science.gov (United States)

    2013-10-23

    ... ] detrivore where plant roots are exposed, providing a medium for microbial growth as well as a food source to... uncertain. Climate change will be a particular challenge for biodiversity in general because the interaction... habitat fragmentation are the most threatening facets of climate change for biodiversity (Hannah and...

  5. Patterns of bacterial diversity across a range of Antarctic terrestrial habitats.

    NARCIS (Netherlands)

    Yergeau, E.; Newsham, K.K.; Pearce, D.A.; Kowalchuk, G.A.

    2007-01-01

    Although soil-borne bacteria represent the world's greatest source of biological diversity, it is not well understood whether extreme environmental conditions, such as those found in Antarctic habitats, result in reduced soil-borne microbial diversity. To address this issue, patterns of bacterial

  6. Patterns of bacterial diversity across a range of Antarctic terrestrial habitats

    NARCIS (Netherlands)

    Yergeau, E.; Newsham, K.K.; Pearce, D.A.; Kowalchuk, G.A.

    2007-01-01

    Although soil-borne bacteria represent the world's greatest source of biological diversity, it is not well understood whether extreme environmental conditions, such as those found in Antarctic habitats, result in reduced soil-borne microbial diversity. To address this issue, patterns of bacterial

  7. Partial gravity habitat study

    Science.gov (United States)

    Capps, Stephen; Lorandos, Jason; Akhidime, Eval; Bunch, Michael; Lund, Denise; Moore, Nathan; Murakawa, Kiosuke

    1989-01-01

    The purpose of this study is to investigate comprehensive design requirements associated with designing habitats for humans in a partial gravity environment, then to apply them to a lunar base design. Other potential sites for application include planetary surfaces such as Mars, variable-gravity research facilities, and a rotating spacecraft. Design requirements for partial gravity environments include locomotion changes in less than normal earth gravity; facility design issues, such as interior configuration, module diameter, and geometry; and volumetric requirements based on the previous as well as psychological issues involved in prolonged isolation. For application to a lunar base, it is necessary to study the exterior architecture and configuration to insure optimum circulation patterns while providing dual egress; radiation protection issues are addressed to provide a safe and healthy environment for the crew; and finally, the overall site is studied to locate all associated facilities in context with the habitat. Mission planning is not the purpose of this study; therefore, a Lockheed scenario is used as an outline for the lunar base application, which is then modified to meet the project needs. The goal of this report is to formulate facts on human reactions to partial gravity environments, derive design requirements based on these facts, and apply the requirements to a partial gravity situation which, for this study, was a lunar base.

  8. Habitat specialization through germination cueing

    DEFF Research Database (Denmark)

    Ten Brink, Dirk-Jan; Hendriksma, Harmen; Bruun, Hans Henrik

    2013-01-01

    This study examined the adaptive association between seed germination ecology and specialization to either forest or open habitats across a range of evolutionary lineages of seed plants, in order to test the hypotheses that (1) species' specialization to open vs. shaded habitats is consistently a...... accompanied by specialization in their regeneration niche; and (2) species are thereby adapted to utilize different windows of opportunity in time (season) and space (habitat)....

  9. Microbial volatile emissions as insect semiochemicals.

    Science.gov (United States)

    Davis, Thomas Seth; Crippen, Tawni L; Hofstetter, Richard W; Tomberlin, Jeffery K

    2013-07-01

    We provide a synthesis of the literature describing biochemical interactions between microorganisms and insects by way of microbial volatile organic compound (MVOC) production. We evaluated the functionality and ecological context of MVOC signals, and explored important metabolic pathways involved in MVOC production. The cosmopolitan distribution of microorganisms creates a context for frequent, and frequently overlooked, insect responses to microbial emissions. There are numerous instances of MVOCs being closely associated with insect feeding behaviors, but some MVOCs are also powerful repellants. Emissions from microorganisms in situ may signal aspects of habitat suitability or potential exposure to entomopathogens. In some ecosystems, bacterial or fungal volatiles can also incite insect aggregations, or MVOCs can resemble sexual pheromones that elicit mating and oviposition behaviors from responding insects. A single microorganism or MVOC can have different effects on insect behaviors, especially across species, ontogenies, and habitats. There appears to be a multipartite basis for insect responses to MVOCs, and complex tritrophic interactions can result from the production of MVOCs. Many biochemical pathways for behaviorally active volatile production by microbial species are conserved across large taxonomic groupings of microorganisms. In addition, there is substantial functional redundancy in MVOCs: fungal tissues commonly produce polyketides and short-chain alcohols, whereas bacterial tissues tend to be more commonly associated with amines and pyrazines. We hypothesize that insect olfactory responses to emissions from microorganisms inhabiting their sensory environment are much more common than currently recognized, and that these signals represent evolutionarily reliable infochemicals. Insect chemoreception of microbial volatiles may contribute to the formation of neutral, beneficial, or even harmful symbioses and provide considerable insight into the

  10. Short-term mesofauna responses to soil additions of corn stover biochar and the role of microbial biomass

    OpenAIRE

    Domene, X. (Xavier)

    2015-01-01

    Biochar additions have been suggested to influence soil microbial communities that, through a cascade effect, may also impact soil fauna. In turn, any direct biochar effects on fauna can influence microbial communities through grazing, physical fragmentation of organic debris (and biochar) and modifying soil structure. If biochar creates a favorable environment for soil microorganisms, it is also plausible for fauna to be attracted to such microbially enriched habitats. However, how soil faun...

  11. ASSESSING LONGITUDINAL THERMAL CONNECTIVITY ...

    Science.gov (United States)

    Water temperature is a key driver of ecological processes in aquatic environments and can influence biological connectivity among riverine habitats. Riverine fish and other mobile aquatic species often must navigate a variety of physical barriers such as dams and culverts. For Pacific salmon, warm water can also pose barriers to migration, but the presence of patches of cooler water within rivers can serve as important refuges and potentially as stepping stones at times of day when temperatures are elsewhere unsuitable along the migratory corridor. Rising water temperature associated with climate change has become a major conservation concern for freshwater species and poses challenges for natural resource managers who must consider multiple factors in addition to uncertainty in climate predictions. Thermal refuges can contribute to watershed-scale thermal resilience and are increasingly considered in water quality regulations; however, monitoring such refuges and effectively operationalizing the concept for management has proved difficult. We review what is known about use of thermal refuges by coldwater fishes in natural systems, and then we present two case study applications in which we characterize thermal patterns in rivers (e.g., the frequency, size, spacing, and location of thermal patches) and consider effects on salmon in a management context. In our first example, we illustrate methods for quantifying spatial heterogeneity in stream temperatures at bi

  12. Microbial electrosynthetic cells

    Energy Technology Data Exchange (ETDEWEB)

    May, Harold D.; Marshall, Christopher W.; Labelle, Edward V.

    2018-01-30

    Methods are provided for microbial electrosynthesis of H.sub.2 and organic compounds such as methane and acetate. Method of producing mature electrosynthetic microbial populations by continuous culture is also provided. Microbial populations produced in accordance with the embodiments as shown to efficiently synthesize H.sub.2, methane and acetate in the presence of CO.sub.2 and a voltage potential. The production of biodegradable and renewable plastics from electricity and carbon dioxide is also disclosed.

  13. Microbial diversity of hypersaline environments: a metagenomic approach.

    Science.gov (United States)

    Ventosa, Antonio; de la Haba, Rafael R; Sánchez-Porro, Cristina; Papke, R Thane

    2015-06-01

    Recent studies based on metagenomics and other molecular techniques have permitted a detailed knowledge of the microbial diversity and metabolic activities of microorganisms in hypersaline environments. The current accepted model of community structure in hypersaline environments is that the square archaeon Haloquadratum waslbyi, the bacteroidete Salinibacter ruber and nanohaloarchaea are predominant members at higher salt concentrations, while more diverse archaeal and bacterial taxa are observed in habitats with intermediate salinities. Additionally, metagenomic studies may provide insight into the isolation and characterization of the principal microbes in these habitats, such as the recently described gammaproteobacterium Spiribacter salinus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  14. Quantitative phylogenetic assessment of microbial communities indiverse environments

    Energy Technology Data Exchange (ETDEWEB)

    von Mering, C.; Hugenholtz, P.; Raes, J.; Tringe, S.G.; Doerks,T.; Jensen, L.J.; Ward, N.; Bork, P.

    2007-01-01

    The taxonomic composition of environmental communities is an important indicator of their ecology and function. Here, we use a set of protein-coding marker genes, extracted from large-scale environmental shotgun sequencing data, to provide a more direct, quantitative and accurate picture of community composition than traditional rRNA-based approaches using polymerase chain reaction (PCR). By mapping marker genes from four diverse environmental data sets onto a reference species phylogeny, we show that certain communities evolve faster than others, determine preferred habitats for entire microbial clades, and provide evidence that such habitat preferences are often remarkably stable over time.

  15. Our cosmic habitat

    CERN Document Server

    Rees, Martin

    2001-01-01

    Our universe seems strangely 'biophilic,' or hospitable to life. Is this providence or coincidence? According to Martin Rees, the answer depends on the answer to another question, the one posed by Einstein's famous remark: 'What interests me most is whether God could have made the world differently.' This highly engaging book centres on the fascinating consequences of the answer being 'yes'. Rees explores the notion that our universe is just part of a vast 'multiverse,' or ensemble of universes, in which most of the other universes are lifeless. What we call the laws of nature would then be local by laws, imposed in the aftermath of our own Big Bang. In this scenario, our cosmic habitat would be a special, possibly unique universe where the prevailing laws of physics allowed life to emerge.

  16. Occupancy in continuous habitat

    Science.gov (United States)

    Efford, Murray G.; Dawson, Deanna K.

    2012-01-01

    The probability that a site has at least one individual of a species ('occupancy') has come to be widely used as a state variable for animal population monitoring. The available statistical theory for estimation when detection is imperfect applies particularly to habitat patches or islands, although it is also used for arbitrary plots in continuous habitat. The probability that such a plot is occupied depends on plot size and home-range characteristics (size, shape and dispersion) as well as population density. Plot size is critical to the definition of occupancy as a state variable, but clear advice on plot size is missing from the literature on the design of occupancy studies. We describe models for the effects of varying plot size and home-range size on expected occupancy. Temporal, spatial, and species variation in average home-range size is to be expected, but information on home ranges is difficult to retrieve from species presence/absence data collected in occupancy studies. The effect of variable home-range size is negligible when plots are very large (>100 x area of home range), but large plots pose practical problems. At the other extreme, sampling of 'point' plots with cameras or other passive detectors allows the true 'proportion of area occupied' to be estimated. However, this measure equally reflects home-range size and density, and is of doubtful value for population monitoring or cross-species comparisons. Plot size is ill-defined and variable in occupancy studies that detect animals at unknown distances, the commonest example being unlimited-radius point counts of song birds. We also find that plot size is ill-defined in recent treatments of "multi-scale" occupancy; the respective scales are better interpreted as temporal (instantaneous and asymptotic) rather than spatial. Occupancy is an inadequate metric for population monitoring when it is confounded with home-range size or detection distance.

  17. Research and Application of Marine Microbial Enzymes: Status and Prospects

    Directory of Open Access Journals (Sweden)

    Chen Zhang

    2010-06-01

    Full Text Available Over billions of years, the ocean has been regarded as the origin of life on Earth. The ocean includes the largest range of habitats, hosting the most life-forms. Competition amongst microorganisms for space and nutrients in the marine environment is a powerful selective force, which has led to evolution. The evolution prompted the marine microorganisms to generate multifarious enzyme systems to adapt to the complicated marine environments. Therefore, marine microbial enzymes can offer novel biocatalysts with extraordinary properties. This review deals with the research and development work investigating the occurrence and bioprocessing of marine microbial enzymes.

  18. Research and Application of Marine Microbial Enzymes: Status and Prospects

    Science.gov (United States)

    Zhang, Chen; Kim, Se-Kwon

    2010-01-01

    Over billions of years, the ocean has been regarded as the origin of life on Earth. The ocean includes the largest range of habitats, hosting the most life-forms. Competition amongst microorganisms for space and nutrients in the marine environment is a powerful selective force, which has led to evolution. The evolution prompted the marine microorganisms to generate multifarious enzyme systems to adapt to the complicated marine environments. Therefore, marine microbial enzymes can offer novel biocatalysts with extraordinary properties. This review deals with the research and development work investigating the occurrence and bioprocessing of marine microbial enzymes. PMID:20631875

  19. Clay Animals and Their Habitats

    Science.gov (United States)

    Adamson, Kay

    2010-01-01

    Creating clay animals and their habitats with second-grade students has long been one of the author's favorite classroom activities. Students love working with clay and they also enjoy drawing animal homes. In this article, the author describes how the students created a diorama instead of drawing their clay animal's habitat. This gave students…

  20. Food technology in space habitats

    Science.gov (United States)

    Karel, M.

    1979-01-01

    The research required to develop a system that will provide for acceptable, nutritious, and safe diets for man during extended space missions is discussed. The development of a food technology system for space habitats capable of converting raw materials produced in the space habitats into acceptable food is examined.

  1. Building habitats on the Moon engineering approaches to lunar settlements

    CERN Document Server

    Benaroya, Haym

    2018-01-01

    Designing a habitat for the lunar surface? You will need to know more than structural engineering. There are the effects of meteoroids, radiation, and low gravity. Then there are the psychological and psychosocial aspects of living in close quarters, in a dangerous environment, far away from home. All these must be considered when the habitat is sized, materials specified, and structure designed. This book provides an overview of various concepts for lunar habitats and structural designs and characterizes the lunar environment - the technical and the nontechnical. The designs take into consideration psychological comfort, structural strength against seismic and thermal activity, as well as internal pressurization and 1/6 g. Also discussed are micrometeoroid modeling, risk and redundancy as well as probability and reliability, with an introduction to analytical tools that can be useful in modeling uncertainties.

  2. Analyses of the microbial diversity across the human microbiome.

    Directory of Open Access Journals (Sweden)

    Kelvin Li

    Full Text Available Analysis of human body microbial diversity is fundamental to understanding community structure, biology and ecology. The National Institutes of Health Human Microbiome Project (HMP has provided an unprecedented opportunity to examine microbial diversity within and across body habitats and individuals through pyrosequencing-based profiling of 16 S rRNA gene sequences (16 S from habits of the oral, skin, distal gut, and vaginal body regions from over 200 healthy individuals enabling the application of statistical techniques. In this study, two approaches were applied to elucidate the nature and extent of human microbiome diversity. First, bootstrap and parametric curve fitting techniques were evaluated to estimate the maximum number of unique taxa, S(max, and taxa discovery rate for habitats across individuals. Next, our results demonstrated that the variation of diversity within low abundant taxa across habitats and individuals was not sufficiently quantified with standard ecological diversity indices. This impact from low abundant taxa motivated us to introduce a novel rank-based diversity measure, the Tail statistic, ("τ", based on the standard deviation of the rank abundance curve if made symmetric by reflection around the most abundant taxon. Due to τ's greater sensitivity to low abundant taxa, its application to diversity estimation of taxonomic units using taxonomic dependent and independent methods revealed a greater range of values recovered between individuals versus body habitats, and different patterns of diversity within habitats. The greatest range of τ values within and across individuals was found in stool, which also exhibited the most undiscovered taxa. Oral and skin habitats revealed variable diversity patterns, while vaginal habitats were consistently the least diverse. Collectively, these results demonstrate the importance, and motivate the introduction, of several visualization and analysis methods tuned specifically for

  3. Providing a sound habitat for man in space

    Science.gov (United States)

    Stranger-Johannessen, Maria

    Microbiological growth on materials in an indoor environment contributes to the well known "sick building syndrome". The inhabitants' health and well-being is affected by injurious vapours and odours given off to the air. This is particularly pronounced in new and better tightened houses with unconventional building materials and wider employment of air conditioning. The European Space Agency has recognized the problems to be expected in a totally closed and self-supported long-term habitat and has induced work on the selection of materials, resistant to microbiological growth, and on other microbial contamination control measures. Requirements and procedures are being established as a basis for the microbiological cleanliness of the manned space environment and for the avoidance of microbiological growth on materials and equipment. Methods are being developed, suitable for testing and predicting the resistivity to microbiological growth of materials to be used in long-term space habitats.

  4. MICROBIAL FUEL CELL

    DEFF Research Database (Denmark)

    2008-01-01

    A novel microbial fuel cell construction for the generation of electrical energy. The microbial fuel cell comprises: (i) an anode electrode, (ii) a cathode chamber, said cathode chamber comprising an in let through which an influent enters the cathode chamber, an outlet through which an effluent...

  5. Coupling Spatiotemporal Community Assembly Processes to Changes in Microbial Metabolism

    Energy Technology Data Exchange (ETDEWEB)

    Graham, Emily B.; Crump, Alex R.; Resch, Charles T.; Fansler, Sarah; Arntzen, Evan; Kennedy, David W.; Fredrickson, Jim K.; Stegen, James C.

    2016-12-16

    Community assembly processes govern shifts in species abundances in response to environmental change, yet our understanding of assembly remains largely decoupled from ecosystem function. Here, we test hypotheses regarding assembly and function across space and time using hyporheic microbial communities as a model system. We pair sampling of two habitat types through hydrologic fluctuation with null modeling and multivariate statistics. We demonstrate that dual selective pressures assimilate to generate compositional changes at distinct timescales among habitat types, resulting in contrasting associations of Betaproteobacteria and Thaumarchaeota with selection and with seasonal changes in aerobic metabolism. Our results culminate in a conceptual model in which selection from contrasting environments regulates taxon abundance and ecosystem function through time, with increases in function when oscillating selection opposes stable selective pressures. Our model is applicable within both macrobial and microbial ecology and presents an avenue for assimilating community assembly processes into predictions of ecosystem function.

  6. Are thermal barriers "higher" in deep sea turtle nests?

    OpenAIRE

    Santidri?n Tomillo, Pilar; Fonseca, Luis; Paladino, Frank V.; Spotila, James R.; Oro, Daniel

    2017-01-01

    Thermal tolerances are affected by the range of temperatures that species encounter in their habitat. Daniel Janzen hypothesized in his "Why mountain passes are higher in the tropics" that temperature gradients were effective barriers to animal movements where climatic uniformity was high. Sea turtles bury their eggs providing some thermal stability that varies with depth. We assessed the relationship between thermal uniformity and thermal tolerance in nests of three species of sea turtles. W...

  7. Operative control of human microflora in confined habitat

    Science.gov (United States)

    Viacheslav, Ilyin; Solovieva, Zoya; Panina, Jana

    The problem of operative control and transmission of information on microbial state of humans in artificial environment is much actual especially in conditions of long-term space missions and in perspective mission to Mars. There was revealed that in long-term missions there is a periodical accumulation of pathogenicity potential in the system "human-microbes" which lead to possible development of opportunistic infections of crew members in spaceflight. To investigate covering tissues microflora of volunteers participated in 14 and 105 days isolation in confined habitat the new non-culture method was elaborated, based on computer treatment of native swab, equally distributed on total surface of microscopy glass and Gram stained. It allows to obtain information on 3 basic indices -morphology, tinctorial and quantitative, thus it could detect increasing of total microbial amount, growth of staphylococci which is important for early diagnostics of microbial disbalance on covering tissues of volunteers. The analysis is performed with the aid of authomatized system of digital microscopy dedicated to recognition of microbial images on the preparate and for further transmission of these digital images via telecommunication network, thus making possibility of remote consultancies. The data of 14-day experiment reveals increasing of potential pathogens on 7th day of isolation with further decrease on 14th day, changes of microflora in 105-day isolation has the tendency of periodical accumulation. In general, the results were compatible with ones obtained by classical bacteriological studies. The results are significant under the microbial quantity of 104 CFU/swab and higher, which is important for analyzing of microbial groups if they grow in quantities, increasing normal values.

  8. The microbiology of deep-sea hydrothermal vent plumes: ecological and biogeographic linkages to seafloor and water column habitats

    Directory of Open Access Journals (Sweden)

    Gregory J Dick

    2013-05-01

    Full Text Available Hydrothermal plumes are an important yet understudied component of deep-sea vent microbial ecosystems. The significance of plume microbial processes can be appreciated from three perspectives: (1 mediation of plume biogeochemistry, (2 dispersal of seafloor hydrothermal vent microbes between vents sites, (3 as natural laboratories for understanding the ecology, physiology, and function of microbial groups that are distributed throughout the pelagic deep sea. Plume microbiology has been largely neglected in recent years, especially relative to the extensive research conducted on seafloor and subseafloor systems. Rapidly advancing technologies for investigating microbial communities provide new motivation and opportunities to characterize this important microbial habitat. Here we briefly highlight microbial contributions to plume and broader ocean (biogeochemistry and review recent work to illustrate the ecological and biogeographic linkages between plumes, seafloor vent habitats, and other marine habitats such as oxygen minimum zones, cold seeps, and oil spills. 16S rRNA gene surveys and metagenomic/-transcriptomic data from plumes point to dominant microbial populations, genes, and functions that are also operative in oxygen minimum zones (SUP05, ammonia-oxidizing Archaea, and SAR324 Deltaproteobacteria and hydrocarbon-rich environments (methanotrophs. Plume microbial communities are distinct from those on the seafloor or in the subsurface but contain some signatures of these habitats, consistent with the notion that plumes are potential vectors for dispersal of microorganisms between seafloor vent sites. Finally, we put forward three pressing questions for the future of deep-sea hydrothermal plume research and consider interactions between vents and oceans on global scales.

  9. Spatial Distribution of Viruses Associated with Planktonic and Attached Microbial Communities in Hydrothermal Environments

    Science.gov (United States)

    Nunoura, Takuro; Kazama, Hiromi; Noguchi, Takuroh; Inoue, Kazuhiro; Akashi, Hironori; Yamanaka, Toshiro; Toki, Tomohiro; Yamamoto, Masahiro; Furushima, Yasuo; Ueno, Yuichiro; Yamamoto, Hiroyuki; Takai, Ken

    2012-01-01

    Viruses play important roles in marine surface ecosystems, but little is known about viral ecology and virus-mediated processes in deep-sea hydrothermal microbial communities. In this study, we examined virus-like particle (VLP) abundances in planktonic and attached microbial communities, which occur in physical and chemical gradients in both deep and shallow submarine hydrothermal environments (mixing waters between hydrothermal fluids and ambient seawater and dense microbial communities attached to chimney surface areas or macrofaunal bodies and colonies). We found that viruses were widely distributed in a variety of hydrothermal microbial habitats, with the exception of the interior parts of hydrothermal chimney structures. The VLP abundance and VLP-to-prokaryote ratio (VPR) in the planktonic habitats increased as the ratio of hydrothermal fluid to mixing water increased. On the other hand, the VLP abundance in attached microbial communities was significantly and positively correlated with the whole prokaryotic abundance; however, the VPRs were always much lower than those for the surrounding hydrothermal waters. This is the first report to show VLP abundance in the attached microbial communities of submarine hydrothermal environments, which presented VPR values significantly lower than those in planktonic microbial communities reported before. These results suggested that viral lifestyles (e.g., lysogenic prevalence) and virus interactions with prokaryotes are significantly different among the planktonic and attached microbial communities that are developing in the submarine hydrothermal environments. PMID:22210205

  10. Architecture and life support systems for a rotating space habitat

    Science.gov (United States)

    Misra, Gaurav

    habitat. In order to ensure Thermal control of the habitat, multiple radiators on the exterior and a thermal shield on the inner circumference of the habitat are proposed. Food production on-board the habitat is proposed to be facilitated through vertical farming systems. These multi-storey farming systems are known to be more efficient in terms of area and sustainable than conventional farms. Agriculture on-board these farms are proposed to be facilitated through hydroponics and enriched regolith. Apart from food production, these farms can cater to fish farming as means of food, animal and insect breeding. In order to ensure waste treatment of organic matter, a biogas plant is proposed in the habitat which can be used to generate electrical or mechanical power .An optimum atmospheric pressure of 51.1Kpa is proposed for the habitat comprising of Oxygen and Helium. Recreational facilities although not directly related to life support systems, play a very important role in optimum liveability of inhabitants. Open spaces, sports facilities, micro gravity swimming pools, orbital hotels are proposed as modes of recreation to ensure long term sustainability for the inhabitants.

  11. Contamination of the Arctic reflected in microbial metagenomes from the Greenland ice sheet

    DEFF Research Database (Denmark)

    Hauptmann, Aviaja Zenia Edna Lyberth; Sicheritz-Pontén, Thomas; Cameron, Karen A.

    2017-01-01

    interact with contamination in the Arctic is limited. Through shotgun metagenomic data and binned genomes from metagenomes we show that microbial communities, sampled from multiple surface ice locations on the Greenland ice sheet, have the potential for resistance to and degradation of contaminants....... The microbial potential to degrade anthropogenic contaminants, such as toxic and persistent polychlorinated biphenyls, was found to be spatially variable and not limited to regions close to human activities. Binned genomes showed close resemblance to microorganisms isolated from contaminated habitats...

  12. Vaccines and Photodynamic Therapies for Oral Microbial-Related Diseases

    OpenAIRE

    Liu, Pei-Feng; Zhu, Wen-Hong; Huang, Chun-Ming

    2009-01-01

    The mouth is a favorable habitat for a great variety of bacteria. Microbial composition of dental plaque is the usual cause of various oral diseases in humans, including dental caries, periodontal disease and halitosis. In general, oral antibacterial agents such as antibiotics are commonly used to treat oral bacterial infection. Traditional periodontal surgery is painful and time-consuming. In addition, bacterial resistance and toxicity of antibiotics have become a global pandemic and unavoid...

  13. Steelhead Critical Habitat, Coast - NOAA [ds122

    Data.gov (United States)

    California Department of Resources — This layer depicts areas designated for Steelhead Critical Habitat as well as habitat type and quality in the Coastal California Steelhead ESUs (evolutionarily...

  14. Riparian Habitat - Product of 2 riparian habitat workshops

    Data.gov (United States)

    California Department of Resources — In two riparian habitat workshops held between 2001 and 2002, scientists and managers identified the need for determining the scope of a consistent and acceptable...

  15. Guam and the Northern Mariana Islands ESI: HABITATS (Habitat Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for benthic marine habitats and plants in Guam and the Northern Mariana Islands. Vector polygons in this...

  16. Southeast Alaska ESI: HABITATS (Habitat and Plant Polygons)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains biological resource data for seagrass habitats in Southeast Alaska. Vector polygons in this data set represent locations of seagrass...

  17. Thermal comfort

    CSIR Research Space (South Africa)

    Osburn, L

    2010-01-01

    Full Text Available wider range of temperature limits, saving energy while still satisfying the majority of building occupants. It is also noted that thermal comfort varies significantly between individuals and it is generally not possible to provide a thermal environment...

  18. Microbial Life in Soil - Linking Biophysical Models with Observations

    Science.gov (United States)

    Or, Dani; Tecon, Robin; Ebrahimi, Ali; Kleyer, Hannah; Ilie, Olga; Wang, Gang

    2015-04-01

    Microbial life in soil occurs within fragmented aquatic habitats formed in complex pore spaces where motility is restricted to short hydration windows (e.g., following rainfall). The limited range of self-dispersion and physical confinement promote spatial association among trophically interdepended microbial species. Competition and preferences for different nutrient resources and byproducts and their diffusion require high level of spatial organization to sustain the functioning of multispecies communities. We report mechanistic modeling studies of competing multispecies microbial communities grown on hydrated surfaces and within artificial soil aggregates (represented by 3-D pore network). Results show how trophic dependencies and cell-level interactions within patchy diffusion fields promote spatial self-organization of motile microbial cells. The spontaneously forming patterns of segregated, yet coexisting species were robust to spatial heterogeneities and to temporal perturbations (hydration dynamics), and respond primarily to the type of trophic dependencies. Such spatially self-organized consortia may reflect ecological templates that optimize substrate utilization and could form the basic architecture for more permanent surface-attached microbial colonies. Hydration dynamics affect structure and spatial arrangement of aerobic and anaerobic microbial communities and their biogeochemical functions. Experiments with well-characterized artificial soil microbial assemblies grown on porous surfaces provide access to community dynamics during wetting and drying cycles detected through genetic fingerprinting. Experiments for visual observations of spatial associations of tagged bacterial species with known trophic dependencies on model porous surfaces are underway. Biophysical modeling provide a means for predicting hydration-mediated critical separation distances for activation of spatial self-organization. The study provides new modeling and observational tools

  19. Habitats and Species Covered by the EEC Habitats Directive

    DEFF Research Database (Denmark)

    Pihl, S.; Søgaard, B.; Ejrnæs, R.

    Under the Habitats Directive (The Council of the European Communities: Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora), Denmark has designated a total of 194 habitats to be included in a European network of Special Areas of Conservat......Under the Habitats Directive (The Council of the European Communities: Council Directive 92/43/EEC of 21 May 1992 on the conservation of natural habitats and of wild fauna and flora), Denmark has designated a total of 194 habitats to be included in a European network of Special Areas...... priority species houting (fish) and hermit (beetle), 4 mammals, 1 reptile, 5 amphibians, 2 dragonflies, and 8 vascular plants. Unfavourable conservation status: 17 species including 2 amphibians, 2 fish, 2 butterflies, 1 dragonfly, 2 beetles, 1 bivalve, 5 vascular plants, and 2 moss-es. Unknown...... conservation status: 13 species including 4 mammals, 1 reptile, 4 fish, 3 snails, and 1 mussel. Disappeared: 13 species including 1 reptile, 2 fish, 3 butterflies, 2 dragonflies, 2 beetles, and 3 mosses. The assessment is based on the preliminary classification of conservation status into these five categories...

  20. Habitat-specific foraging of prothonotary warblers: Deducing habitat quality

    Science.gov (United States)

    Lyons, J.E.

    2005-01-01

    Foraging behavior often reflects food availability in predictable ways. For example, in habitats where food availability is high, predators should attack prey more often and move more slowly than in habitats where food availability is low. To assess relative food availability and habitat quality, I studied the foraging behavior of breeding Prothonotary Warblers (Protonotaria citrea) in two forest habitat types, cypress-gum swamp forest and coastal-plain levee forest. I quantified foraging behavior with focal animal sampling and continuous recording during foraging bouts. I measured two aspects of foraging behavior: 1) prey attack rate (attacks per minute), using four attack maneuvers (glean, sally, hover, strike), and 2) foraging speed (movements per minute), using three types of movement (hop, short flight [???1 m], long flight [>1 m]). Warblers attacked prey more often in cypress-gum swamp forest than in coastal-plain levee forest. Foraging speed, however, was not different between habitats. I also measured foraging effort (% time spent foraging) and relative frequency of attack maneuvers employed in each habitat; neither of these variables was influenced by forest type. I conclude that Prothonotary Warblers encounter more prey when foraging in cypress-gum swamps than in coastal-plain levee forest, and that greater food availability results in higher density and greater reproductive success for birds breeding in cypress-gum swamp.

  1. Protection of Antarctic microbial communities – ‘out of sight, out of mind’

    Directory of Open Access Journals (Sweden)

    Kevin Andrew Hughes

    2015-02-01

    Full Text Available Recent advances in molecular biology techniques have shown the presence of diverse microbial communities and endemic species in Antarctica. Endemic microbes may be a potential source of novel biotechnologically important compounds, including, for example, new antibiotics. Thus, the scientific and biotechnological value of Antarctic terrestrial microbial habitats can be compromised by human visitation to a greater extent than previously realized. The ever-increasing human footprint in Antarctica makes consideration of this topic more pressing, as the number of locations known to be pristine habitats, where increasingly sophisticated cutting-edge research techniques may be used to their full potential, declines. Examination of the Protected Areas system of the Antarctic Treaty shows that microbial habitats are generally poorly protected. No other continent on Earth is dominated to the same degree by microbial species, and real opportunities exist to develop new ways of conceptualising and implementing conservation of microbial biogeography on a continental scale. Here we highlight potential threats both to the conservation of terrestrial microbial ecosystems, and to future scientific research requiring their study.

  2. Gammarus-Microbial Interactions: A Review

    Directory of Open Access Journals (Sweden)

    Daniel Nelson

    2011-01-01

    Full Text Available Gammarus spp. are typically classified as shredders under the functional feeding group classification. In the wild and in the laboratory, Gammarus spp. will often shred leaves, breaking them down into finer organic matter fractions. However, leaf litter is a poor quality food source (i.e., high C : N and C : P ratios and very little leaf material is assimilated by shredders. In freshwater habitats leaf litter is colonized rapidly (within ∼1-2 weeks by aquatic fungi and bacteria, making the leaves more palatable and nutritious to consumers. Several studies have shown that Gammarus spp. show preference for conditioned leaves over nonconditioned leaves and certain fungal species to others. Furthermore, Gammarus spp. show increased survival and growth rates when fed conditioned leaves compared to non-conditioned leaves. Thus, Gammarus spp. appear to rely on the microbial biofilm associated with leaf detritus as a source of carbon and/or essential nutrients. Also, Gammarus spp. can have both positive and negative effects on the microbial communities on which they fed, making them an important component of the microbial loop in aquatic ecosystems.

  3. Deep Space Habitat Concept Demonstrator

    Science.gov (United States)

    Bookout, Paul S.; Smitherman, David

    2015-01-01

    This project will develop, integrate, test, and evaluate Habitation Systems that will be utilized as technology testbeds and will advance NASA's understanding of alternative deep space mission architectures, requirements, and operations concepts. Rapid prototyping and existing hardware will be utilized to develop full-scale habitat demonstrators. FY 2014 focused on the development of a large volume Space Launch System (SLS) class habitat (Skylab Gen 2) based on the SLS hydrogen tank components. Similar to the original Skylab, a tank section of the SLS rocket can be outfitted with a deep space habitat configuration and launched as a payload on an SLS rocket. This concept can be used to support extended stay at the Lunar Distant Retrograde Orbit to support the Asteroid Retrieval Mission and provide a habitat suitable for human missions to Mars.

  4. Tidal Creek Sentinel Habitat Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Ecological Research, Assessment and Prediction's Tidal Creeks: Sentinel Habitat Database was developed to support the National Oceanic and Atmospheric...

  5. Riparian Habitat - San Joaquin River

    Data.gov (United States)

    California Department of Resources — The immediate focus of this study is to identify, describe and map the extent and diversity of riparian habitats found along the main stem of the San Joaquin River,...

  6. Shrub-Scrub Habitat Evaluation

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Conversion of the current shrub-scrub habitats west of Sandpiper Road and north of the Back BayNational Wildlife Refuge, into recreational facilities for a new hotel...

  7. Autonomous Systems: Habitat Automation Element

    Data.gov (United States)

    National Aeronautics and Space Administration — We define a habitat fairly broadly to include any enclosed space that is intended to house people for an extended period of time away from the Earth....

  8. Endangered Species Act Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Critical habitat (CH) is designated for the survival and recovery of species listed as threatened or endangered under the Endangered Species Act (ESA). Critical...

  9. Leatherback Sea Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for leatherback turtle as designated by Federal Register Vol. 44, No. 17711, March 23, 1979, Rules and Regulations....

  10. Hawksbill Sea Turtle Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for hawksbill turtle as designated by Federal Register Vol. 63, No. 46701, September 2, 1998, Rules and Regulations....

  11. Habitat--Offshore Monterey, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Monterey map area, California. The vector data file is included in...

  12. Allelopathy-mediated competition in microbial mats from Antarctic lakes.

    Science.gov (United States)

    Slattery, Marc; Lesser, Michael P

    2017-05-01

    Microbial mats are vertically stratified communities that host a complex consortium of microorganisms, dominated by cyanobacteria, which compete for available nutrients and environmental niches, within these extreme habitats. The Antarctic Dry Valleys near McMurdo Sound include a series of lakes within the drainage basin that are bisected by glacial traverses. These lakes are traditionally independent, but recent increases in glacial melting have allowed two lakes (Chad and Hoare) to become connected by a meltwater stream. Microbial mats were collected from these lakes, and cultured under identical conditions at the McMurdo Station laboratory. Replicate pairings of the microbial mats exhibited consistent patterns of growth inhibition indicative of competitive dominance. Natural products were extracted from the microbial mats, and a disk diffusion assay was utilized to show that allelochemical compounds mediate competitive interactions. Both microscopy and 16S rRNA sequencing show that these mats contain significant populations of cyanobacteria known to produce allelochemicals. Two compounds were isolated from these microbial mats that might be important in the chemical ecology of these psychrophiles. In other disk:mat pairings, including extract versus mat of origin, the allelochemicals exhibited no effect. Taken together, these results indicate that Antarctic lake microbial mats can compete via allelopathy. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  13. Requirements for modeling airborne microbial contamination in space stations

    Science.gov (United States)

    Van Houdt, Rob; Kokkonen, Eero; Lehtimäki, Matti; Pasanen, Pertti; Leys, Natalie; Kulmala, Ilpo

    2018-03-01

    Exposure to bioaerosols is one of the facets that affect indoor air quality, especially for people living in densely populated or confined habitats, and is associated to a wide range of health effects. Good indoor air quality is thus vital and a prerequisite for fully confined environments such as space habitats. Bioaerosols and microbial contamination in these confined space stations can have significant health impacts, considering the unique prevailing conditions and constraints of such habitats. Therefore, biocontamination in space stations is strictly monitored and controlled to ensure crew and mission safety. However, efficient bioaerosol control measures rely on solid understanding and knowledge on how these bioaerosols are created and dispersed, and which factors affect the survivability of the associated microorganisms. Here we review the current knowledge gained from relevant studies in this wide and multidisciplinary area of bioaerosol dispersion modeling and biological indoor air quality control, specifically taking into account the specific space conditions.

  14. Are mountain habitats becoming more suitable for generalist than cold-adapted lizards thermoregulation?

    Directory of Open Access Journals (Sweden)

    Zaida Ortega

    2016-05-01

    Full Text Available Mountain lizards are highly vulnerable to climate change, and the continuous warming of their habitats could be seriously threatening their survival. We aim to compare the thermal ecology and microhabitat selection of a mountain lizard, Iberolacerta galani, and a widely distributed lizard, Podarcis bocagei, in a montane area. Both species are currently in close syntopy in the study area, at 1,400 m above the sea level. We determined the precision, accuracy and effectiveness of thermoregulation, and the thermal quality of habitat for both species. We also compared the selection of thermal microhabitats between both species. Results show that I. galani is a cold-adapted thermal specialist with a preferred temperature range of 27.9–29.7 °C, while P. bocagei would be a thermal generalist, with a broader and higher preferred temperature range (30.1–34.5 °C. In addition, I. galani selects rocky substrates while P. bocagei selects warmer soil and leaf litter substrates. The thermal quality of the habitat is higher for P. bocagei than for I. galani. Finally, P. bocagei achieves a significantly higher effectiveness of thermoregulation (0.87 than I. galani (0.80. Therefore, these mountain habitat conditions seem currently more suitable for performance of thermophilic generalist lizards than for cold-specialist lizards.

  15. Biodiversity in urban habitat patches.

    Science.gov (United States)

    Angold, P G; Sadler, J P; Hill, M O; Pullin, A; Rushton, S; Austin, K; Small, E; Wood, B; Wadsworth, R; Sanderson, R; Thompson, K

    2006-05-01

    We examined the biodiversity of urban habitats in Birmingham (England) using a combination of field surveys of plants and carabid beetles, genetic studies of four species of butterflies, modelling the anthropochorous nature of the floral communities and spatially explicit modelling of selected mammal species. The aim of the project was to: (i) understand the ecological characteristics of the biota of cities model, (ii) examine the effects of habitat fragment size and connectivity upon the ecological diversity and individual species distributions, (iii) predict biodiversity in cities, and (iv) analyse the extent to which the flora and fauna utilise the 'urban greenways' both as wildlife corridors and as habitats in their own right. The results suggest that cities provide habitats for rich and diverse range of plants and animals, which occur sometimes in unlikely recombinant communities. The studies on carabids and butterflies illustrated the relative importance of habitat quality on individual sites as opposed to site location within the conurbation. This suggests that dispersal for most of our urban species is not a limiting factor in population persistence, although elements of the woodland carabid fauna did appear to have some geographical structuring. Theoretical models suggested that dormice and water voles may depend on linear habitats for dispersal. The models also indicated that other groups, such as small and medium sized mammals, may use corridors, although field-based research did not provide any evidence to suggest that plants or invertebrates use urban greenways for dispersal. This finding indicates the importance of identifying a target species or group of species for urban greenways intended as dispersal routeways rather than as habitat in their own right. Their importance for most groups is rather that greenways provide a chain of different habitats permeating the urban environment. We suggest that planners can have a positive impact on urban

  16. Uncultured archaea dominate in the thermal groundwater of Uzon Caldera, Kamchatka.

    Science.gov (United States)

    Mardanov, Andrey V; Gumerov, Vadim M; Beletsky, Alexey V; Perevalova, Anna A; Karpov, Gennady A; Bonch-Osmolovskaya, Elizaveta A; Ravin, Nikolai V

    2011-05-01

    The thermoacidophilic microbial community inhabiting the groundwater with pH 4.0 and temperature 50°C at the East Thermal Field of Uzon Caldera, Kamchatka, was examined using pyrosequencing of the V3 region of the 16S rRNA gene. Bacteria comprise about 30% of microorganisms and are represented primarily by aerobic lithoautotrophs using the energy sources of volcanic origin--thermoacidophilic methanotrophs of the phylum Verrucomicrobia and Acidithiobacillus spp. oxidising metals and reduced sulfur compounds. More than 70% of microbial population in this habitat were represented by archaea, in majority affiliated with "uncultured" lineages. The most numerous group (39% of all archaea) represented a novel division in the phylum Euryarchaeota related to the order Thermoplasmatales. Another abundant group (33% of all archaea) was related to MCG1 lineage of the phylum Crenarchaeota, originally detected in the Yellowstone hot spring as the environmental clone pJP89. The organisms belonging to these two groups are widely spread in hydrothermal environments worldwide. These data indicate an important environmental role of these two archaeal groups and should stimulate the investigation of their metabolism by cultivation or metagenomic approaches.

  17. Geopressured habitat: A literature review

    Energy Technology Data Exchange (ETDEWEB)

    Negus-de Wys, Jane

    1992-09-01

    A literature review of the geopressured-geothermal habitat is summarized. Findings are presented and discussed with respect to the principal topics: Casual agents are both geological and geochemical; they include disequilibrium compaction of sediments, clay diagenesis, aquathermal pressuring, hydrocarbon generation, and lateral tectonic compression. The overall physical and chemical characteristics of the habitats are dictated by varying combinations of sedimentation rates, alteration mineralogy, permeability, porosity and pressure, temperature, fluid content and chemistry, and hydrodynamic flow. Habitat pressure seals are considered in terms of their formation processes, geologic characteristics, and physical behavior, including pressure release and reservoir pressure recharge on a geologic time scale. World-wide occurrence of geopressured-geothermal habitats is noted. The main thrust of this topic concerns the U.S.A. and Canada; in addition, reference is made to occurrences in China and indications from deep-sea vents, as well as the contribution of paleo-overpressure to habitat initiation and maintenance. Identification and assessment of the habitat is addressed in relation to use of hydrogeologic, geophysical, geochemical, and geothermic techniques, as well as well-logging and drill-stem-test data. Conclusions concerning the adequacy of the current state of knowledge and its applicability to resource exploration and development are set forth, together with recommendations for the thrust of future work.

  18. Microbial activity in the marine deep biosphere: progress and prospects.

    Science.gov (United States)

    Orcutt, Beth N; Larowe, Douglas E; Biddle, Jennifer F; Colwell, Frederick S; Glazer, Brian T; Reese, Brandi Kiel; Kirkpatrick, John B; Lapham, Laura L; Mills, Heath J; Sylvan, Jason B; Wankel, Scott D; Wheat, C Geoff

    2013-01-01

    The vast marine deep biosphere consists of microbial habitats within sediment, pore waters, upper basaltic crust and the fluids that circulate throughout it. A wide range of temperature, pressure, pH, and electron donor and acceptor conditions exists-all of which can combine to affect carbon and nutrient cycling and result in gradients on spatial scales ranging from millimeters to kilometers. Diverse and mostly uncharacterized microorganisms live in these habitats, and potentially play a role in mediating global scale biogeochemical processes. Quantifying the rates at which microbial activity in the subsurface occurs is a challenging endeavor, yet developing an understanding of these rates is essential to determine the impact of subsurface life on Earth's global biogeochemical cycles, and for understanding how microorganisms in these "extreme" environments survive (or even thrive). Here, we synthesize recent advances and discoveries pertaining to microbial activity in the marine deep subsurface, and we highlight topics about which there is still little understanding and suggest potential paths forward to address them. This publication is the result of a workshop held in August 2012 by the NSF-funded Center for Dark Energy Biosphere Investigations (C-DEBI) "theme team" on microbial activity (www.darkenergybiosphere.org).

  19. Microbial activity in the marine deep biosphere: Progress and prospects

    Directory of Open Access Journals (Sweden)

    Beth N Orcutt

    2013-07-01

    Full Text Available The vast marine deep biosphere consists of microbial habitats within sediment, pore waters, upper basaltic crust and the fluids that circulate throughout it. A wide range of temperature, pressure, pH, and electron donor and acceptor conditions exists – all of which can combine to affect carbon and nutrient cycling and result in gradients on spatial scales ranging from millimeters to kilometers. Diverse and mostly uncharacterized microorganisms live in these habitats, and potentially play a role in mediating global scale biogeochemical processes. Quantifying the rates at which microbial activity in the subsurface occurs is a challenging endeavor, yet developing an understanding of these rates is essential to determine the impact of subsurface life on Earth's global biogeochemical cycles, and for understanding how microorganisms in these "extreme" environments survive (or even thrive. Here, we synthesize recent advances and discoveries pertaining to microbial activity in the marine deep subsurface, and we highlight topics about which there is still little understanding and suggest potential paths forward to address them. This publication is the result of a workshop held in August 2012 by the NSF-funded Center for Dark Energy Biosphere Investigations (C-DEBI "theme team" on microbial activity (www.darkenergybiosphere.org.

  20. Microbial activity in the marine deep biosphere: progress and prospects

    Science.gov (United States)

    Orcutt, Beth N.; LaRowe, Douglas E.; Biddle, Jennifer F.; Colwell, Frederick S.; Glazer, Brian T.; Reese, Brandi Kiel; Kirkpatrick, John B.; Lapham, Laura L.; Mills, Heath J.; Sylvan, Jason B.; Wankel, Scott D.; Wheat, C. Geoff

    2013-01-01

    The vast marine deep biosphere consists of microbial habitats within sediment, pore waters, upper basaltic crust and the fluids that circulate throughout it. A wide range of temperature, pressure, pH, and electron donor and acceptor conditions exists—all of which can combine to affect carbon and nutrient cycling and result in gradients on spatial scales ranging from millimeters to kilometers. Diverse and mostly uncharacterized microorganisms live in these habitats, and potentially play a role in mediating global scale biogeochemical processes. Quantifying the rates at which microbial activity in the subsurface occurs is a challenging endeavor, yet developing an understanding of these rates is essential to determine the impact of subsurface life on Earth's global biogeochemical cycles, and for understanding how microorganisms in these “extreme” environments survive (or even thrive). Here, we synthesize recent advances and discoveries pertaining to microbial activity in the marine deep subsurface, and we highlight topics about which there is still little understanding and suggest potential paths forward to address them. This publication is the result of a workshop held in August 2012 by the NSF-funded Center for Dark Energy Biosphere Investigations (C-DEBI) “theme team” on microbial activity (www.darkenergybiosphere.org). PMID:23874326

  1. Microbial community assembly and metabolic function during mammalian corpse decomposition

    Energy Technology Data Exchange (ETDEWEB)

    Metcalf, J. L.; Xu, Z. Z.; Weiss, S.; Lax, S.; Van Treuren, W.; Hyde, E. R.; Song, S. J.; Amir, A.; Larsen, P.; Sangwan, N.; Haarmann, D.; Humphrey, G. C.; Ackermann, G.; Thompson, L. R.; Lauber, C.; Bibat, A.; Nicholas, C.; Gebert, M. J.; Petrosino, J. F.; Reed, S. C.; Gilbert, J. A.; Lynne, A. M.; Bucheli, S. R.; Carter, D. O.; Knight, R.

    2015-12-10

    Vertebrate corpse decomposition provides an important stage in nutrient cycling in most terrestrial habitats, yet microbially mediated processes are poorly understood. Here we combine deep microbial community characterization, community-level metabolic reconstruction, and soil biogeochemical assessment to understand the principles governing microbial community assembly during decomposition of mouse and human corpses on different soil substrates. We find a suite of bacterial and fungal groups that contribute to nitrogen cycling and a reproducible network of decomposers that emerge on predictable time scales. Our results show that this decomposer community is derived primarily from bulk soil, but key decomposers are ubiquitous in low abundance. Soil type was not a dominant factor driving community development, and the process of decomposition is sufficiently reproducible to offer new opportunities for forensic investigations.

  2. Microbial Monitoring Challenges and Needs for Mars Applications

    Science.gov (United States)

    Roman, M. C.; Ott, C. M.; Castro, V. A.; Birmele, M. N.; Roberts, M. S.; Venkateswaran, K. J.; Jan, D. L.

    2012-01-01

    The monitoring of microorganisms will be an important part of a mission to Mars. Microbial monitoring equipment will be needed to look for the presence of microorganisms on the planet, to confirm that planetary protection measures are working, to monitor the health of plants, bioreactors and humans living in a habitat and to monitor the performance of the life support systems that will keep them alive during their stay on Mars. Coordinating the different microbial monitoring needs during the early days of mission planning, can provide NASA with equipment that could meet more than one need while also providing complementary analysis options, which can enhance the research capabilities. The early coordination between the different NASA groups that will need microbial monitoring equipment on the surface of Mars, could also make the mission more affordable, as development of the needed equipment could be potentially cost shared.

  3. Microbial community assembly and metabolic function during mammalian corpse decomposition

    Science.gov (United States)

    Metcalf, Jessica L; Xu, Zhenjiang Zech; Weiss, Sophie; Lax, Simon; Van Treuren, Will; Hyde, Embriette R.; Song, Se Jin; Amir, Amnon; Larsen, Peter; Sangwan, Naseer; Haarmann, Daniel; Humphrey, Greg C; Ackermann, Gail; Thompson, Luke R; Lauber, Christian; Bibat, Alexander; Nicholas, Catherine; Gebert, Matthew J; Petrosino, Joseph F; Reed, Sasha C.; Gilbert, Jack A; Lynne, Aaron M; Bucheli, Sibyl R; Carter, David O; Knight, Rob

    2016-01-01

    Vertebrate corpse decomposition provides an important stage in nutrient cycling in most terrestrial habitats, yet microbially mediated processes are poorly understood. Here we combine deep microbial community characterization, community-level metabolic reconstruction, and soil biogeochemical assessment to understand the principles governing microbial community assembly during decomposition of mouse and human corpses on different soil substrates. We find a suite of bacterial and fungal groups that contribute to nitrogen cycling and a reproducible network of decomposers that emerge on predictable time scales. Our results show that this decomposer community is derived primarily from bulk soil, but key decomposers are ubiquitous in low abundance. Soil type was not a dominant factor driving community development, and the process of decomposition is sufficiently reproducible to offer new opportunities for forensic investigations.

  4. Microbial characteristics of biogas.

    Science.gov (United States)

    Moletta, Marina; Wery, Nathalie; Delgenes, Jean-Philippe; Godon, Jean-Jacques

    2008-01-01

    The microbial diversity of biogas was analyzed in order to examine the aerosolization behavior of microorganisms. Six biogas samples were analyzed: five from mesophilic and thermophilic anaerobic digestors treating different wastes, and one from landfill. Epifluorescent microscopic counts revealed 10(6) prokarya m(-3). To assess the difference occuring in aerosolization, 498 biogas-borne 16S ribosomal DNA were analyzed and compared to published anaerobic digestor microbial diversity. Results show a large microbial diversity and strong discrepancy with digestor microbial diversity. Three different aerosolisation behaviour patterns can be identified: (i) that of non-aerosolized microorganisms, Deltaproteobacteria, Spirochaetes, Thermotogae, Chloroflexi phyla and sulfate-reducing groups, (ii) that of passively aerosolized microorganisms, including Actinobacteria, Firmicutes and Bacteroidetes phyla and (iii) that of preferentially aerosolized microorganisms, including Alphaproteobacteria, Betaproteobacteria, Gammaproteobacteria, as well as strictly aerobic and occasionally pathogenic species, presented high levels of aerosolization.

  5. Functional diversity of marine macrobenthic communities from sublittoral soft-sediment habitats off northern Chile

    Science.gov (United States)

    Pacheco, Aldo S.; González, Maria Teresa; Bremner, Julie; Oliva, Marcelo; Heilmayer, Olaf; Laudien, Jürgen; Riascos, José M.

    2011-09-01

    Benthic communities show changes in composition and structure across different environmental characteristics and habitats. However, incorporating species biological traits into the analysis can provide a better understanding of system functioning within habitats. We compare the functional diversity of macrobenthic communities from a contrasting shallow (15 m) and deep (50 m) sublittoral soft-sediment habitats in northern Chile, using biological traits analysis. Our aim was to highlight the biological characteristics responsible for differences between habitats and the implications for ecosystem functioning. Trait analysis showed that the deep habitat was restricted in providing functionally important biogenic structure and bioturbation and supports less diverse feeding-related energy pathways. The shallow habitat is characterized by more diverse energy pathways and a higher potential for matter exchange through bioturbation. We provide support to the predictions of transfer of energy from the benthos to upper trophic levels in the shallow, which is characterized mainly by normoxia and little organic matter content in the sediment. In the deep habitat, characterized by hypoxia and more organic matter, energy appears to be transferred to microbial components. We suggest that trait analysis should be added to the traditional approaches based on species diversity, because it provides indicators of ecosystem stress.

  6. Evolution of Thermal Reaction Norms in Seasonally Varying Environments.

    Science.gov (United States)

    Amarasekare, Priyanga; Johnson, Christopher

    2017-03-01

    Thermal reaction norms of ectotherms exhibit a distinctive latitudinal pattern: the temperature at which performance is maximized coincides with the mean habitat temperature in tropical ectotherms but exceeds the mean temperature in temperate ectotherms. We hypothesize, on the basis of Jensen's inequality, that this pattern is driven by latitudinal variation in seasonal temperature fluctuations. We test this hypothesis with an eco-evolutionary model that integrates the quantitative genetics of reaction norm evolution with stage-structured population dynamics, which we parameterize with data from insects. We find that thermal optima of temperate and Mediterranean species evolve to exceed the mean habitat temperature if seasonal fluctuations are strong, while the thermal optimum of tropical species evolves to coincide with the mean habitat temperature if fluctuations are weak. Importantly, ecological dynamics can impose a constraint on reaction norm evolution. Tropical species cannot tolerate an increase in seasonal fluctuations at the high mean habitat temperature it experiences, while the temperate species cannot tolerate a reduction in seasonal fluctuations if the mean temperature is higher. In both cases, stochastic extinction during periods of low abundances precludes adaptation to a novel thermal environment. Our findings suggest a potential directionality in colonization success. Tropical ectotherms, because of their high thermal optima, can successfully colonize temperate habitats, while temperate ectotherms, because of their low optima, are less successful in colonizing tropical habitats.

  7. A NEW HABITAT CLASSIFICATION AND MANUAL FOR STANDARDIZED HABITAT MAPPING

    Directory of Open Access Journals (Sweden)

    J. BOLONI

    2007-04-01

    Full Text Available Today the documentation of natural heritage with scientific methods but for conservation practice – like mapping of actual vegetation – becomes more and more important. For this purpose mapping guides containing only the names and descriptions of vegetation types are not sufficient. Instead, new, mapping-oriented vegetation classification systems and handbooks are needed. There are different standardised systems fitted to the characteristics of a region already published and used successfully for surveying large territories. However, detailed documentation of the aims and steps of their elaboration is still missing. Here we present a habitat-classification method developed specifically for mapping and the steps of its development. Habitat categories and descriptions reflect site conditions, physiognomy and species composition as well. However, for species composition much lower role was given deliberately than in the phytosociological systems. Recognition and mapping of vegetation types in the field is highly supported by a definition, list of subtypes and list of ‘types not belonging to this habitat category’. Our system is two-dimensional: the first dimension is habitat type, the other is naturalness based habitat quality. The development of the system was conducted in two steps, over 200 mappers already tested it over 7000 field days in different projects.

  8. A NEW HABITAT CLASSIFICATION AND MANUAL FOR STANDARDIZED HABITAT MAPPING

    Directory of Open Access Journals (Sweden)

    A. KUN

    2007-01-01

    Full Text Available Today the documentation of natural heritage with scientific methods but for conservation practice – like mapping of actual vegetation – becomes more and more important. For this purpose mapping guides containing only the names and descriptions of vegetation types are not sufficient. Instead, new, mapping-oriented vegetation classification systems and handbooks are needed. There are different standardised systems fitted to the characteristics of a region already published and used successfully for surveying large territories. However, detailed documentation of the aims and steps of their elaboration is still missing. Here we present a habitat-classification method developed specifically for mapping and the steps of its development. Habitat categories and descriptions reflect site conditions, physiognomy and species composition as well. However, for species composition much lower role was given deliberately than in the phytosociological systems. Recognition and mapping of vegetation types in the field is highly supported by a definition, list of subtypes and list of ‘types not belonging to this habitat category’. Our system is two-dimensional: the first dimension is habitat type, the other is naturalness based habitat quality. The development of the system was conducted in two steps, over 200 mappers already tested it over 7000 field days in different projects.

  9. Microbial bioinformatics 2020.

    Science.gov (United States)

    Pallen, Mark J

    2016-09-01

    Microbial bioinformatics in 2020 will remain a vibrant, creative discipline, adding value to the ever-growing flood of new sequence data, while embracing novel technologies and fresh approaches. Databases and search strategies will struggle to cope and manual curation will not be sustainable during the scale-up to the million-microbial-genome era. Microbial taxonomy will have to adapt to a situation in which most microorganisms are discovered and characterised through the analysis of sequences. Genome sequencing will become a routine approach in clinical and research laboratories, with fresh demands for interpretable user-friendly outputs. The "internet of things" will penetrate healthcare systems, so that even a piece of hospital plumbing might have its own IP address that can be integrated with pathogen genome sequences. Microbiome mania will continue, but the tide will turn from molecular barcoding towards metagenomics. Crowd-sourced analyses will collide with cloud computing, but eternal vigilance will be the price of preventing the misinterpretation and overselling of microbial sequence data. Output from hand-held sequencers will be analysed on mobile devices. Open-source training materials will address the need for the development of a skilled labour force. As we boldly go into the third decade of the twenty-first century, microbial sequence space will remain the final frontier! © 2016 The Author. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  10. Amplicon-Metagenomic Analysis of Fungi from Antarctic Terrestrial Habitats

    Directory of Open Access Journals (Sweden)

    Marcelo Baeza

    2017-11-01

    Full Text Available In cold environments such as polar regions, microorganisms play important ecological roles, and most of our knowledge about them comes from studies of cultivable microorganisms. Metagenomic technologies are powerful tools that can give a more comprehensive assessment of microbial communities, and the amplification of rDNA followed by next-generation sequencing has given good results in studies aimed particularly at environmental microorganisms. Culture-independent studies of microbiota in terrestrial habitats of Antarctica, which is considered the driest, coldest climate on Earth, are increasing and indicate that micro-diversity is much higher than previously thought. In this work, the microbial diversity of terrestrial habitats including eight islands of the South Shetland Archipelago, two islands on the Antarctic Peninsula and Union Glacier, was studied by amplicon-metagenome analysis. Molecular analysis of the studied localities clustered together the islands of the South Shetland Archipelago, except Greenwich Island, and separated them from the Litchfield and Lagotellerie islands and Union Glacier, which is in agreement with the latitudinal difference among them. Among fungi, 87 genera and 123 species were found, of which species belonging to 37 fungal genera not previously cultivated from Antarctica were detected. Phylogenetic analysis, including the closest BLAST-hit sequences, clustered fungi in 11 classes being the most represented Lecanoromycetes and Eurotiomycetes.

  11. Bacterial phylogeny structures soil resistomes across habitats

    Science.gov (United States)

    Forsberg, Kevin J.; Patel, Sanket; Gibson, Molly K.; Lauber, Christian L.; Knight, Rob; Fierer, Noah; Dantas, Gautam

    2014-05-01

    Ancient and diverse antibiotic resistance genes (ARGs) have previously been identified from soil, including genes identical to those in human pathogens. Despite the apparent overlap between soil and clinical resistomes, factors influencing ARG composition in soil and their movement between genomes and habitats remain largely unknown. General metagenome functions often correlate with the underlying structure of bacterial communities. However, ARGs are proposed to be highly mobile, prompting speculation that resistomes may not correlate with phylogenetic signatures or ecological divisions. To investigate these relationships, we performed functional metagenomic selections for resistance to 18 antibiotics from 18 agricultural and grassland soils. The 2,895 ARGs we discovered were mostly new, and represent all major resistance mechanisms. We demonstrate that distinct soil types harbour distinct resistomes, and that the addition of nitrogen fertilizer strongly influenced soil ARG content. Resistome composition also correlated with microbial phylogenetic and taxonomic structure, both across and within soil types. Consistent with this strong correlation, mobility elements (genes responsible for horizontal gene transfer between bacteria such as transposases and integrases) syntenic with ARGs were rare in soil by comparison with sequenced pathogens, suggesting that ARGs may not transfer between soil bacteria as readily as is observed between human pathogens. Together, our results indicate that bacterial community composition is the primary determinant of soil ARG content, challenging previous hypotheses that horizontal gene transfer effectively decouples resistomes from phylogeny.

  12. Microbial communities associated with benthic faunal assemblages at cold seep sediments of the Sonora Margin, Guaymas Basin

    Directory of Open Access Journals (Sweden)

    Perrine eCruaud

    2015-08-01

    Full Text Available The Sonora Margin cold seeps present a seafloor mosaic pattern consisting of different faunal assemblages and microbial mats. To better understand if sedimentary microbial communities reflect this patchy distribution, all major habitats were investigated using four complementary approaches: 16S rRNA 454 pyrosequencing, quantitative polymerase chain reaction, fluorescence in situ hybridization and geochemistry analyses. This study reveals that sediments populated by different surface assemblages show distinct porewater geochemistry features and are associated with distinct microbial communities. In the sediments underlying the microbial mat and the surrounding macrofauna, microbial communities were dominated by anaerobic methane oxidizers (archaeal anaerobic methanotroph ANME and sulfate-reducing Deltaproteobacteria. In contrast, sediment-associated microbial communities underlying the megafauna habitats (vesicomyids and siboglinids were characterized by a lower biomass and important proportions of the Marine Benthic Group D (MBG-D, Chloroflexi as well as filamentous Gammaproteobacteria and Deltaproteobacteria. Together, geochemical and microbial surveys indicate that porewater methane concentrations play an important role in the microbial community structure and subsequently in the establishment of the surface colonizers. Furthermore, presence and activity of the surface colonizers influence the underlying microbial communities probably because of modification of energy source availabilities.

  13. Determining habitat quality for species that demonstrate dynamic habitat selection

    Science.gov (United States)

    Beerens, James M.; Frederick, Peter C; Noonburg, Erik G; Gawlik, Dale E.

    2015-01-01

    Determining habitat quality for wildlife populations requires relating a species' habitat to its survival and reproduction. Within a season, species occurrence and density can be disconnected from measures of habitat quality when resources are highly seasonal, unpredictable over time, and patchy. Here we establish an explicit link among dynamic selection of changing resources, spatio-temporal species distributions, and fitness for predictive abundance and occurrence models that are used for short-term water management and long-term restoration planning. We used the wading bird distribution and evaluation models (WADEM) that estimate (1) daily changes in selection across resource gradients, (2) landscape abundance of flocks and individuals, (3) conspecific foraging aggregation, and (4) resource unit occurrence (at fixed 400 m cells) to quantify habitat quality and its consequences on reproduction for wetland indicator species. We linked maximum annual numbers of nests detected across the study area and nesting success of Great Egrets (Ardea alba), White Ibises (Eudocimus albus), and Wood Storks (Mycteria americana) over a 20-year period to estimated daily dynamics of food resources produced by WADEM over a 7490 km2 area. For all species, increases in predicted species abundance in March and high abundance in April were strongly linked to breeding responses. Great Egret nesting effort and success were higher when birds also showed greater conspecific foraging aggregation. Synthesis and applications: This study provides the first empirical evidence that dynamic habitat selection processes and distributions of wading birds over environmental gradients are linked with reproductive measures over periods of decades. Further, predictor variables at a variety of temporal (daily-multiannual) resolutions and spatial (400 m to regional) scales effectively explained variation in ecological processes that change habitat quality. The process used here allows managers to develop

  14. Spatial variability of Chinook salmon spawning distribution and habitat preferences

    Science.gov (United States)

    Cram, Jeremy M.; Torgersen, Christian; Klett, Ryan S.; Pess, George R.; May, Darran; Pearsons, Todd N.; Dittman, Andrew H.

    2017-01-01

    We investigated physical habitat conditions associated with the spawning sites of Chinook Salmon Oncorhynchus tshawytscha and the interannual consistency of spawning distribution across multiple spatial scales using a combination of spatially continuous and discrete sampling methods. We conducted a census of aquatic habitat in 76 km of the upper main-stem Yakima River in Washington and evaluated spawning site distribution using redd survey data from 2004 to 2008. Interannual reoccupation of spawning areas was high, ranging from an average Pearson’s correlation of 0.62 to 0.98 in channel subunits and 10-km reaches, respectively. Annual variance in the interannual correlation of spawning distribution was highest in channel units and subunits, but it was low at reach scales. In 13 of 15 models developed for individual years (2004–2008) and reach lengths (800 m, 3 km, 6 km), stream power and depth were the primary predictors of redd abundance. Multiple channels and overhead cover were patchy but were important secondary and tertiary predictors of reach-scale spawning site selection. Within channel units and subunits, pool tails and thermal variability, which may be associated with hyporheic exchange, were important predictors of spawning. We identified spawning habitat preferences within reaches and channel units that are relevant for salmonid habitat restoration planning. We also identified a threshold (i.e., 2-km reaches) beyond which interannual spawning distribution was markedly consistent, which may be informative for prioritizing habitat restoration or conservation. Management actions may be improved through enhanced understanding of spawning habitat preferences and the consistency with which Chinook Salmon reoccupy spawning areas at different spatial scales.

  15. Microbial mediators of carbon fate in thawing permafrost: connecting microbial activity to geochemistry across an in situ thaw gradient

    Science.gov (United States)

    Kim, E.; Mondav, R.; Woodcroft, B. J.; Hodgkins, S. B.; McCalley, C. K.; Wehr, R.; Logan, T.; VerBerkmoes, N. C.; Crill, P. M.; Chanton, J.; Saleska, S. R.; Rich, V. I.; Tyson, G. W.

    2012-12-01

    Permafrost holds approximately one third of global soil carbon in a relatively unavailable form. Climate change is predicted to virtually eliminate permafrost by the end of the century. The fate of the stored carbon will be driven by local geohydrology and mediated by microbial carbon transformations. Predicting thaw-induced feedbacks to climate change requires improving our understanding of concomitant changes in microbial activity, particularly in CO2 fixation, organic matter degradation, and CH4 cycling. Our team is using diverse geochemical and molecular measurements to track changes in carbon cycling and microbial communities across a natural permafrost thaw gradient. The gradient habitats are highly instrumented for ecological, hydrologic, and biogeochemical monitoring, and the thaw progression has been documented over decades. Permafrost thaw has caused slumping ground level and progressive changes in hydrology and plant composition, culminating in sedge-dominated fen wetland. Although this endpoint habitat supports higher plant productivity, there is a net increase in radiative forcing due to high methane emissions. This natural laboratory permits the examination of in situ changes in microbial composition and activity across thaw-induced habitat change. Specifically, taxonomic and metabolic profiling (16S rRNA gene amplicon, metagenomic and metaproteomic sequencing) is linking microbial metabolisms to synoptic geochemistry. Community data have revealed the presence of a novel highly active methanogen from the euryarchaeal lineage Rice Cluster-II. The abundance and distribution of RC-II across the thaw gradient habitats correlate to methane emission. The 2.1Mb RC-II genome (in 117 contigs, median 47kb, longest 135kb) was assembled from metagenomic data. The genome suggests the ability to perform hydrogenotrophic methanogenesis. To link resident microbes to active carbon cycling, we determined in situ community global protein expression profiles (i

  16. The effects of chemical interactions and culture history on the colonization of structured habitats by competing bacterial populations

    NARCIS (Netherlands)

    Van Vliet, S.; Hol, F.J.H.; Weenink, T.; Galajda, P.; Keymer, J.E.

    2014-01-01

    Background Bacterial habitats, such as soil and the gut, are structured at the micrometer scale. Important aspects of microbial life in such spatial ecosystems are migration and colonization. Here we explore the colonization of a structured ecosystem by two neutrally labeled strains of Escherichia

  17. Living in sympatry: The effect of habitat partitioning on the thermoregulation of three Mediterranean lizards.

    Science.gov (United States)

    Sagonas, Kostas; Kapsalas, Grigoris; Valakos, Efstratios; Pafilis, Panayiotis

    2017-04-01

    The ability for effective, accurate and precise thermoregulation is of paramount importance for ectotherms. Sympatric lizards often partition their niche and select different microhabitats. These microhabitats, however, usually differ in their thermal conditions and lizards have to adapt their thermoregulation behavior accordingly. Here, we evaluated the impact of habitat partitioning on the thermal biology of three syntopic, congeneric lacertids (Podarcis peloponnesiacus, P. tauricus and P. muralis) from central Peloponnese, Greece. We assessed thermoregulation effectiveness (E) using the three standard thermal parameters: body (T b ), operative (T e ) and preferred (T pref ) temperatures. We hypothesized that the microhabitats used by each species would differ in thermal quality. We also predicted that all species would effectively thermoregulate, as they inhabit a thermally challenging mountain habitat. As expected, the partition of the habitat had an effect on the thermoregulation of lizards since microhabitats had different thermal qualities. All three species were effective and accurate thermoregulators but one of them achieved smaller E values as a result of the lower T b in the field. This discrepancy could be attributed to the cooler (but more benign) thermal microhabitats that this species occupies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  18. Growth and functioning of the microbial plankton community: effects of temperature, nutrients and light

    NARCIS (Netherlands)

    Brauer, V.S.

    2015-01-01

    Microbial plankton form the basis of the food web in aquatic habitats. Due to their vast abundances they influence the cycling of elements and the Earth’s climate at a global scale. This thesis aims at a better understanding of how environmental factors such as temperature and the availability of

  19. Soil microbial invasions : Patterns, mechanisms, and impacts garnered from Escherichia coli invasions into soil

    NARCIS (Netherlands)

    Mallon, Cyrus Alexander

    2015-01-01

    Microbiële invasies zijn er in vele vormen. Ze kunnen de vorm hebben van een infectie die we oplopen, de probiotica die we eten of de natuurlijke groei van microben buiten hun habitat. De processen, patronen, en mechanismen die een invasie controleren waren tot voor kort onbekend. In dit

  20. Habitats: staging life and art

    DEFF Research Database (Denmark)

    Andersen, Peter Bøgh

    2004-01-01

    The paper presents the concept of habitat. It is a bounded chunk of space/time that isdesigned to accommodate a delimited set of activities. It accommodates the activities by in-cludingphysical artefacts that can be used in the activities and signs that offer activity-relevantinformation. The hab......The paper presents the concept of habitat. It is a bounded chunk of space/time that isdesigned to accommodate a delimited set of activities. It accommodates the activities by in-cludingphysical artefacts that can be used in the activities and signs that offer activity......-relevantinformation. The habitat concept was originally proposed as a help to understandmobile context-sensitive technology, but turns out to have much broader applications. Thepresent version of the approach uses activity theory and semiotics as the basic theoretical un-derpinnings.The paper offers a notation for specifying...

  1. Trapping Triatominae in Silvatic Habitats

    Directory of Open Access Journals (Sweden)

    Noireau François

    2002-01-01

    Full Text Available Large-scale trials of a trapping system designed to collect silvatic Triatominae are reported. Live-baited adhesive traps were tested in various ecosystems and different triatomine habitats (arboreal and terrestrial. The trials were always successful, with a rate of positive habitats generally over 20% and reaching 48.4% for palm trees of the Amazon basin. Eleven species of Triatominae belonging to the three genera of public health importance (Triatoma, Rhodnius and Panstrongylus were captured. This trapping system provides an effective way to detect the presence of triatomines in terrestrial and arboreal silvatic habitats and represents a promising tool for ecological studies. Various lines of research are contemplated to improve the performance of this trapping system.

  2. Habitat Suitability Index Models: Mink

    Science.gov (United States)

    Allen, Arthur W.

    1983-01-01

    The mink (Mustela vison) is a predatory, semiaquatic mammal that is generally associated with stream and river banks, lake shores, fresh and saltwater marshes, and marine shore habitats (Gerell 1970).  Mink are chiefly nocturnal and remain active throughout the year (Marshall 1936); Gerell 1969; Burgess 1978).  The species is adaptable in its use of habitat, modifying daily habits according to environmental conditions, particularly prey availability (Wise et al. 1981; Linn and Birds 1981; Birks and Linn 1982).  The species is tolerant of human activity and will inhabit suboptimum habitats as long as an adequate food source is available; however, mink will be more mobile and change home ranges more frequently under such conditions (Linn pers. comm.).

  3. Loss and modification of habitat

    Science.gov (United States)

    Lemckert, Francis; Hecnar, Stephen; Pilliod, David S.; Wilkinson, John W.; Heatwole, Harold

    2012-01-01

    Amphibians live in a wide variety of habitats around the world, many of which have been modified or destroyed by human activities. Most species have unique life history characteristics adapted to specific climates, habitats (e.g., lentic, lotic, terrestrial, arboreal, fossorial, amphibious), and local conditions that provide suitable areas for reproduction, development and growth, shelter from environmental extremes, and predation, as well as connectivity to other populations or habitats. Although some species are entirely aquatic or terrestrial, most amphibians, as their name implies, lead a dual life and require a mosaic of habitats in both aquatic and terrestrial ecosystems. With over 6 billion people on Earth, most species are now persisting in habitats that have been directly or indirectly influenced by human activities. Some species have disappeared where their habitats have been completely destroyed, reduced, or rendered unsuitable. Habitat loss and degradation are widely considered by most researchers as the most important causes of amphibian population decline globally (Barinaga 1990; Wake and Morowitz 1991; Alford and Richards 1999). In this chapter, a background on the diverse habitat requirements of amphibians is provided, followed by a discussion of the effects of urbanization, agriculture, livestock grazing, timber production and harvesting, fire and hazardous fuel management, and roads on amphibians and their habitats. Also briefly discussed is the influence on amphibian habitats of natural disturbances, such as extreme weather events and climate change, given the potential for human activities to impact climate in the longer term. For amphibians in general, microhabitats are of greater importance than for other vertebrates. As ectotherms with a skin that is permeable to water and with naked gelatinous eggs, amphibians are physiologically constrained to be active during environmental conditions that provide appropriate body temperatures and adequate

  4. Geomorphology and Sustainable Subsistence Habitats

    Science.gov (United States)

    Johnson, A. C.; Kruger, L. E.

    2016-02-01

    Climatic, tectonic, and human-related impacts are changing the distribution of shoreline habitats and associated species used as food resources. There is a need to summarize current and future shoreline geomorphic - biotic relationships and better understand potential impacts to native customary and traditional gathering patterns. By strategically integrating Native knowledge and observations, we create an inclusive vulnerability assessment strategy resulting in a win-win opportunity for resource users and research scientists alike. We merged the NOAA ShoreZone database with results from over sixty student intern discussions in six southeast Alaska Native communities. Changes in shore width and unit length were derived using near shore bathymetry depths and available isostatic rebound, tectonic movement, and rates of sea level rise. Physical attributes including slope, substrate, and exposure were associated with presence and abundance of specific species. Student interns, selected by Tribes and Tribal associations, conducted resource-based discussions with community members to summarize species use, characteristics of species habitat, transportation used to access collection areas, and potential threats to habitats. Geomorphic trends and community observations were summarized to assess potential threats within a spatial context. Given current measured rates of uplift and sea level rise, 2.4 to 0 m of uplift along with 0.20 m of sea level rise is expected in the next 100 years. Coastlines of southeast Alaska will be subject to both drowning (primarily to the south) and emergence (primarily to the north). We predict decreases in estuary and sediment-dominated shoreline length and an increase in rocky habitats. These geomorphic changes, combined with resident's concerns, highlight six major interrelated coastal vulnerabilities including: (1) reduction of clam and clam habitat quantity and quality, (2) reduction in chiton quality and quantity, (3) harmful expansion of

  5. Restoring and rehabilitating sagebrush habitats

    Science.gov (United States)

    Pyke, David A.; Knick, S.T.; Connelly, J.W.

    2011-01-01

    Less than half of the original habitat of the Greater Sage-Grouse (Centrocercus uropha-sianus) currently exists. Some has been perma-nently lost to farms and urban areas, but the remaining varies in condition from high quality to no longer adequate. Restoration of sagebrush (Artemisia spp.) grassland ecosystems may be pos-sible for resilient lands. However, Greater Sage-Grouse require a wide variety of habitats over large areas to complete their life cycle. Effective restoration will require a regional approach for prioritizing and identifying appropriate options across the landscape. A landscape triage method is recommended for prioritizing lands for restora-tion. Spatial models can indicate where to protect and connect intact quality habitat with other simi-lar habitat via restoration. The ecological site con-cept of land classification is recommended for characterizing potential habitat across the region along with their accompanying state and transi-tion models of plant community dynamics. These models assist in identifying if passive, manage-ment-based or active, vegetation manipulation?based restoration might accomplish the goals of improved Greater Sage-Grouse habitat. A series of guidelines help formulate questions that manag-ers might consider when developing restoration plans: (1) site prioritization through a landscape triage; (2) soil verification and the implications of soil features on plant establishment success; (3) a comparison of the existing plant community to the potential for the site using ecological site descriptions; (4) a determination of the current successional status of the site using state and transition models to aid in predicting if passive or active restoration is necessary; and (5) implemen-tation of post-treatment monitoring to evaluate restoration effectiveness and post-treatment man-agement implications to restoration success.

  6. Microbial Ecology of the Dark Ocean above, at, and below the Seafloor†

    Science.gov (United States)

    Orcutt, Beth N.; Sylvan, Jason B.; Knab, Nina J.; Edwards, Katrina J.

    2011-01-01

    Summary: The majority of life on Earth—notably, microbial life—occurs in places that do not receive sunlight, with the habitats of the oceans being the largest of these reservoirs. Sunlight penetrates only a few tens to hundreds of meters into the ocean, resulting in large-scale microbial ecosystems that function in the dark. Our knowledge of microbial processes in the dark ocean—the aphotic pelagic ocean, sediments, oceanic crust, hydrothermal vents, etc.—has increased substantially in recent decades. Studies that try to decipher the activity of microorganisms in the dark ocean, where we cannot easily observe them, are yielding paradigm-shifting discoveries that are fundamentally changing our understanding of the role of the dark ocean in the global Earth system and its biogeochemical cycles. New generations of researchers and experimental tools have emerged, in the last decade in particular, owing to dedicated research programs to explore the dark ocean biosphere. This review focuses on our current understanding of microbiology in the dark ocean, outlining salient features of various habitats and discussing known and still unexplored types of microbial metabolism and their consequences in global biogeochemical cycling. We also focus on patterns of microbial diversity in the dark ocean and on processes and communities that are characteristic of the different habitats. PMID:21646433

  7. Thermal infrared remote sensing sensors, methods, applications

    CERN Document Server

    Kuenzer, Claudia

    2013-01-01

    This book provides a comprehensive overview of the state of the art in the field of thermal infrared remote sensing. Temperature is one of the most important physical environmental variables monitored by earth observing remote sensing systems. Temperature ranges define the boundaries of habitats on our planet. Thermal hazards endanger our resources and well-being. In this book renowned international experts have contributed chapters on currently available thermal sensors as well as innovative plans for future missions. Further chapters discuss the underlying physics and image processing techni

  8. Habitat classification modelling with incomplete data: Pushing the habitat envelope

    Science.gov (United States)

    Phoebe L. Zarnetske; Thomas C. Edwards; Gretchen G. Moisen

    2007-01-01

    Habitat classification models (HCMs) are invaluable tools for species conservation, land-use planning, reserve design, and metapopulation assessments, particularly at broad spatial scales. However, species occurrence data are often lacking and typically limited to presence points at broad scales. This lack of absence data precludes the use of many statistical...

  9. HabitatSpace: Multidimensional Characterization of Pelagic Essential Fish Habitat

    Science.gov (United States)

    2010-06-01

    Date: 1796 1 a: the place or environment where a plant or animal naturally or normally lives and grows b: the typical place of residence of a person or...3 Marxan - http://www.uq.edu.au/marxan/, HabitatDigitizer - http://ccma.nos.noaa.gov/products/ biogeography /digitizer/, EcoPath

  10. Microbial Fossils Detected in Desert Varnish

    Science.gov (United States)

    Flood, B. E.; Allen, C.; Longazo, T.

    2003-01-01

    Mars Global Surveyor Thermal Emission Spectrometer data indicate regions with significant levels of hematite (_Fe2O3). Fe-oxides, like hematite, can form as aqueous mineral precipitates and as such may preserve microscopic fossils or other biosignatures. Several potential terrestrial analogues to martian hematite like hydrothermal vents have preserved microfossils. Microbial fossilization in Fe-oxides is often a function of biomineralization. For example, goethite (FeO2H) encrustation of fungal mycelia from the mid-Tertiary preserved fungal morphologies such that their genera could be determined.

  11. Microbial ecology and biogeochemistry of continental Antarctic soils

    Directory of Open Access Journals (Sweden)

    Don A Cowan

    2014-04-01

    Full Text Available The Antarctica Dry Valleys are regarded as the coldest hyperarid desert system on Earth. While a wide variety of environmental stressors including very low minimum temperatures, frequent freeze-thaw cycles and low water availability impose severe limitations to life, suitable niches for abundant microbial colonization exist. Antarctic desert soils contain much higher levels of microbial diversity than previously thought. Edaphic niches, including cryptic and refuge habitats, microbial mats and permafrost soils all harbour microbial communities which drive key biogeochemical cycling processes. For example, lithobionts (hypoliths and endoliths possess a genetic capacity for nitrogen and carbon cycling, polymer degradation and other system processes. Nitrogen fixation rates of hypoliths, as assessed through acetylene reduction assays, suggest that these communities are a significant input source for nitrogen into these oligotrophic soils. Here we review aspects of microbial diversity in Antarctic soils with an emphasis on functionality and capacity. We assess current knowledge regarding adaptations to Antarctic soil environments and highlight the current threats to Antarctic desert soil communities.

  12. Wide boundaries of microbial life as due to anabiosis

    Science.gov (United States)

    Abyzov, S. A.; Mulyukin, A. L.; Mitskevich, I. N.; Ivanov, M. V.

    Gaining more insights to the boundaries in which microbial life can exist came from comprehensive studies of various especially extreme terrestrial environments They differ in their origin age temperature salinity energy flux and many other factors that are of paramount importance for life sustenance Microbiological studies of ancient Antarctic glaciers gave experimentally substantiated information on time and the lowest boundary of temperature in which viable pro- and eukaryotic microbial cells survived Noticeably the total number of viable microorganisms that are present in Antarctic ice horizons with temperature varying from -50 oC to -2 4 oC and the age range from 0 2 to 500 thousands of years The existence of microbial cells in so widely ranging temperature and age is regarded as due to super-long anabiosis Theoretically there is no difference between microorganisms that existed in the anabiotic state for tens of hundreds to millennia of years if they faced to low temperatures Hence wide boundaries of microbial life are associated to the state of anabiosis and this is true not only for deep cold environments such as Antarctic glaciers Indeed sensational findings of viable microorganisms in a variety of terrestrial ancient objects extend our knowledge of life boundaries Revelations of ancient microbial cells especially in those habitats where the number of microorganisms is very low unavoidably concerns the problem of authentication Therefore it is great importance to develop and use the methods that exclude contamination of studied samples by

  13. Differences in intertidal microbial assemblages on urban structures and natural rocky reef

    Directory of Open Access Journals (Sweden)

    Elisa Lee Yan Tan

    2015-11-01

    Full Text Available Global seascapes are increasingly modified to support high levels of human activity in the coastal zone. Modifications include the addition of defense structures and boating infrastructure, such as seawalls and marinas that replace natural habitats. Artificial structures support different macrofaunal communities to those found on natural rocky shores; however, little is known about differences in microbial community structure or function in urban seascapes. Understanding how artificial constructions in marine environments influence microbial communities is important as these assemblages contribute to many basic ecological processes. In this study, the bacterial communities of intertidal biofilms were compared between artificial structures (seawalls and natural habitats (rocky shores within Sydney Harbour. Plots were cleared on each type of habitat at 8 locations. After 3 weeks the newly formed biofilm was sampled and the 16S rRNA gene sequenced using the Illumina Miseq platform. To account for differences in orientation and substrate material between seawalls and rocky shores that might have influenced our survey, we also deployed recruitment blocks next to the habitats at all locations for 3 weeks and then sampled and sequenced their microbial communities. Intertidal bacterial community structure sampled from plots differed between seawalls and rocky shores, but when substrate material, age and orientation were kept constant (with recruitment blocks then bacterial communities were similar in composition and structure among habitats. This suggests that changes in bacterial communities on seawalls are not related to environmental differences between locations, but may be related to other intrinsic factors that differ between the habitats such as orientation, complexity or predation. This is one of the first comparisons of intertidal microbial communities on natural and artificial surfaces and illustrates substantial ecological differences with

  14. In four shallow and mesophotic tropical reef sponges from Guam the microbial community largely depends on host identity

    OpenAIRE

    Georg Steinert; Taylor, Michael W.; Peter Deines; Simister, Rachel L.; Nicole J. de Voogd; Michael Hoggard; Schupp, Peter J.

    2016-01-01

    Sponges (phylum Porifera) are important members of almost all aquatic ecosystems, and are renowned for hosting often dense and diverse microbial communities. While the specificity of the sponge microbiota seems to be closely related to host phylogeny, the environmental factors that could shape differences within local sponge-specific communities remain less understood. On tropical coral reefs, sponge habitats can span from shallow areas to deeper, mesophotic sites. These habitats differ in te...

  15. Community Structure of Lithotrophically-Driven Hydrothermal Microbial Mats from the Mariana Arc and Back-Arc.

    Science.gov (United States)

    Hager, Kevin W; Fullerton, Heather; Butterfield, David A; Moyer, Craig L

    2017-01-01

    The Mariana region exhibits a rich array of hydrothermal venting conditions in a complex geological setting, which provides a natural laboratory to study the influence of local environmental conditions on microbial community structure as well as large-scale patterns in microbial biogeography. We used high-throughput amplicon sequencing of the bacterial small subunit (SSU) rRNA gene from 22 microbial mats collected from four hydrothermally active locations along the Mariana Arc and back-arc to explore the structure of lithotrophically-based microbial mat communities. The vent effluent was classified as iron- or sulfur-rich corresponding with two distinct community types, dominated by either Zetaproteobacteria or Epsilonproteobacteria, respectively. The Zetaproteobacterial-based communities had the highest richness and diversity, which supports the hypothesis that Zetaproteobacteria function as ecosystem engineers creating a physical habitat within a chemical environment promoting enhanced microbial diversity. Gammaproteobacteria were also high in abundance within the iron-dominated mats and some likely contribute to primary production. In addition, we also compare sampling scale, showing that bulk sampling of microbial mats yields higher diversity than micro-scale sampling. We present a comprehensive analysis and offer new insights into the community structure and diversity of lithotrophically-driven microbial mats from a hydrothermal region associated with high microbial biodiversity. Our study indicates an important functional role of for the Zetaproteobacteria altering the mat habitat and enhancing community interactions and complexity.

  16. Microbial Biodiversity: Approaches to Experimental Design and Hypothesis Testing in Primary Scientific Literature from 1975 to 1999

    OpenAIRE

    Morris, Cindy E.; Bardin, Marc; Berge, Odile; Frey-Klett, Pascale; Fromin, Nathalie; Girardin, Hélène; Guinebretière, Marie-Hélène; Lebaron, Philippe; Thiéry, Jean M.; Troussellier, Marc

    2002-01-01

    Research interest in microbial biodiversity over the past 25 years has increased markedly as microbiologists have become interested in the significance of biodiversity for ecological processes and as the industrial, medical, and agricultural applications of this diversity have evolved. One major challenge for studies of microbial habitats is how to account for the diversity of extremely large and heterogeneous populations with samples that represent only a very small fraction of these populat...

  17. Lower Hatchie Forest Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Lower Hatchie National Wildlife Refuge Forest Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources of...

  18. Stream Habitat Reach Summary - NCWAP [ds158

    Data.gov (United States)

    California Department of Resources — The Stream Habitat - NCWAP - Reach Summary [ds158] shapefile contains in-stream habitat survey data summarized to the stream reach level. It is a derivative of the...

  19. Fish Springs National Wildlife Refuge habitat map

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Habitat map for Fish Springs National Wildlife Refuge. This habitat map was created along with the National Vegetation Classification (NVC) map of the refuge. Refuge...

  20. Lacassine National Wildlife Refuge Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Lacassine National Wildlife Refuge Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources of concern at...

  1. Benthic Habitats of the Florida Keys

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The benthic habitats of the Florida Keys were mapped from a series of 450 aerial photographs. Ecologists outlined the boundaries of specific habitat types by...

  2. Pacific Northwest Salmon Habitat Project Database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — In the Pacific Northwest Salmon Habitat Project Database Across the Pacific Northwest, both public and private agents are working to improve riverine habitat for a...

  3. Chinook Critical Habitat, Coast - NOAA [ds124

    Data.gov (United States)

    California Department of Resources — This layer depicts areas designated for Chinook Critical Habitat as well as habitat type and quality in the California Coastal Evolutionary Significant Unit (ESU -...

  4. Mandalay National Wildlife Refuges Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Mandalay NWR Habitat Management Plan provides a long-term vision and specific guidance on managing habitats for the resources of concern at the Refuge, to...

  5. Habitat Appraisal by Vermont Electric Power Company

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Declines in habitat availability have been associated with population declines in bird species breeding in early successional forest and shrubland habitats....

  6. White Lake AOC Habitat Restoration Project

    Science.gov (United States)

    The Muskegon Conservation District and the White Lake Public Advisory Council in 2012 completed the White Lake AOC Shoreline Habitat Restoration Project to address the loss of shoreline and nearshore habitat.

  7. Beaked Whale Habitat Characterization and Prediction

    National Research Council Canada - National Science Library

    Ward, Jessica A; Mitchell, Glenn H; Farak, Amy M; Keane, Ellen P

    2005-01-01

    The objective of this study was to characterize known beaked whale habitat and create a predictive beaked whale habitat model of the Gulf of Mexico and east coast of the United States using available...

  8. The vesicomyid bivalve habitat at cold seeps supports heterogeneous and dynamic macrofaunal assemblages

    Science.gov (United States)

    Guillon, Erwan; Menot, Lénaïck; Decker, Carole; Krylova, Elena; Olu, Karine

    2017-02-01

    The high biodiversity found at cold seeps, despite elevated concentrations of methane and hydrogen sulfide, is attributed to multiple sources of habitat heterogeneity. In addition to geological and geochemical processes, biogenic habitats formed by large symbiont-bearing taxa, such as bivalves and siboglinid tubeworms, or by microbial mats drive the biodiversity of small-sized fauna. However, because these habitat-forming species also depend on geochemical gradients, the respective influence of abiotic and biotic factors in structuring associated macrofaunal communities is often unresolved. The giant pockmark Regab located at 3200 m depth on the Congo margin is characterized by different fluid-flow regimes, providing a mosaic of the most common biogenic habitats encountered at seeps: microbial mats, mussel beds, and vesicomyid clam beds; the latter being distributed along a gradient of environmental conditions from the center to the periphery of the pockmark. Here, we examined the structure of macrofaunal communities in biogenic habitats formed in soft sediment to (1) determine the influence of the habitats on the associated macrofaunal communities (inter-habitat comparison), (2) describe how macrofaunal communities vary among vesicomyid clam beds (intra-habitat comparison) and (3) assess the inter-annual variation in vesicomyid beds based on repeated sampling at a three-year interval. The highest densities were found in the microbial mat communities in intermediate fluid-flow areas, but they had low diversity - also observed in the sediment close to mussel beds. In contrast, vesicomyid beds harbored the highest diversity. The vesicomyid beds did not show a homogeneous macrofaunal community across sampled areas; instead, density and composition of macrofauna varied according to the location of the beds inside the pockmark. The clam bed sampled in the most active, central part of the pockmark resembled bacterial mat communities by the presence of highly sulfide

  9. Microbial ecology of Thailand tsunami and non-tsunami affected terrestrials.

    Science.gov (United States)

    Somboonna, Naraporn; Wilantho, Alisa; Jankaew, Kruawun; Assawamakin, Anunchai; Sangsrakru, Duangjai; Tangphatsornruang, Sithichoke; Tongsima, Sissades

    2014-01-01

    The effects of tsunamis on microbial ecologies have been ill-defined, especially in Phang Nga province, Thailand. This ecosystem was catastrophically impacted by the 2004 Indian Ocean tsunami as well as the 600 year-old tsunami in Phra Thong island, Phang Nga province. No study has been conducted to elucidate their effects on microbial ecology. This study represents the first to elucidate their effects on microbial ecology. We utilized metagenomics with 16S and 18S rDNA-barcoded pyrosequencing to obtain prokaryotic and eukaryotic profiles for this terrestrial site, tsunami affected (S1), as well as a parallel unaffected terrestrial site, non-tsunami affected (S2). S1 demonstrated unique microbial community patterns than S2. The dendrogram constructed using the prokaryotic profiles supported the unique S1 microbial communities. S1 contained more proportions of archaea and bacteria domains, specifically species belonging to Bacteroidetes became more frequent, in replacing of the other typical floras like Proteobacteria, Acidobacteria and Basidiomycota. Pathogenic microbes, including Acinetobacter haemolyticus, Flavobacterium spp. and Photobacterium spp., were also found frequently in S1. Furthermore, different metabolic potentials highlighted this microbial community change could impact the functional ecology of the site. Moreover, the habitat prediction based on percent of species indicators for marine, brackish, freshwater and terrestrial niches pointed the S1 to largely comprise marine habitat indicating-species.

  10. Microbial ecology of Thailand tsunami and non-tsunami affected terrestrials.

    Directory of Open Access Journals (Sweden)

    Naraporn Somboonna

    Full Text Available The effects of tsunamis on microbial ecologies have been ill-defined, especially in Phang Nga province, Thailand. This ecosystem was catastrophically impacted by the 2004 Indian Ocean tsunami as well as the 600 year-old tsunami in Phra Thong island, Phang Nga province. No study has been conducted to elucidate their effects on microbial ecology. This study represents the first to elucidate their effects on microbial ecology. We utilized metagenomics with 16S and 18S rDNA-barcoded pyrosequencing to obtain prokaryotic and eukaryotic profiles for this terrestrial site, tsunami affected (S1, as well as a parallel unaffected terrestrial site, non-tsunami affected (S2. S1 demonstrated unique microbial community patterns than S2. The dendrogram constructed using the prokaryotic profiles supported the unique S1 microbial communities. S1 contained more proportions of archaea and bacteria domains, specifically species belonging to Bacteroidetes became more frequent, in replacing of the other typical floras like Proteobacteria, Acidobacteria and Basidiomycota. Pathogenic microbes, including Acinetobacter haemolyticus, Flavobacterium spp. and Photobacterium spp., were also found frequently in S1. Furthermore, different metabolic potentials highlighted this microbial community change could impact the functional ecology of the site. Moreover, the habitat prediction based on percent of species indicators for marine, brackish, freshwater and terrestrial niches pointed the S1 to largely comprise marine habitat indicating-species.

  11. 11 Soil Microbial Biomass

    African Journals Online (AJOL)

    A field experiment to monitor the dynamics of microbial biomass carbon, nitrogen and phosphorus under amendments and cropping ... Biomass carbon showed positive correlations with soil organic carbon with r values of 0.71, 0.40 and 0.64 in 2006 (major) .... (Jenkinson, 1988; Ross & Tate, 1993) were used, respectively.

  12. Microbial Energy Conversion

    Energy Technology Data Exchange (ETDEWEB)

    Buckley, Merry [American Society for Microbiology (ASM), Washington, DC (United States); Wall, Judy D. [Univ. of Missouri, Columbia, MO (United States)

    2006-10-01

    The American Academy of Microbiology convened a colloquium March 10-12, 2006, in San Francisco, California, to discuss the production of energy fuels by microbial conversions. The status of research into various microbial energy technologies, the advantages and disadvantages of each of these approaches, research needs in the field, and education and training issues were examined, with the goal of identifying routes for producing biofuels that would both decrease the need for fossil fuels and reduce greenhouse gas emissions. Currently, the choices for providing energy are limited. Policy makers and the research community must begin to pursue a broader array of potential energy technologies. A diverse energy portfolio that includes an assortment of microbial energy choices will allow communities and consumers to select the best energy solution for their own particular needs. Funding agencies and governments alike need to prepare for future energy needs by investing both in the microbial energy technologies that work today and in the untested technologies that will serve the world’s needs tomorrow. More mature bioprocesses, such as ethanol production from starchy materials and methane from waste digestors, will find applications in the short term. However, innovative techniques for liquid fuel or biohydrogen production are among the longer term possibilities that should also be vigorously explored, starting now. Microorganisms can help meet human energy needs in any of a number of ways. In their most obvious role in energy conversion, microorganisms can generate fuels, including ethanol, hydrogen, methane, lipids, and butanol, which can be burned to produce energy. Alternatively, bacteria can be put to use in microbial fuel cells, where they carry out the direct conversion of biomass into electricity. Microorganisms may also be used some day to make oil and natural gas technologies more efficient by sequestering carbon or by assisting in the recovery of oil and

  13. Microbial transport systems

    National Research Council Canada - National Science Library

    Winkelmann, Günther

    2001-01-01

    ... transport is the plasma membrane, which may be accompanied by an outer membrane in the case of gram-negative bacteria. Due to their long evolutionary development, microbial cells are the most diverse with respect to transport. The various mechanisms of solute transport across these membranes are so diverse that it is surprising that cells can manage...

  14. Microbial solubilization of coal

    Science.gov (United States)

    Strandberg, G.W.; Lewis, S.N.

    1988-01-21

    The present invention relates to a cell-free preparation and process for the microbial solubilization of coal into solubilized coal products. More specifically, the present invention relates to bacterial solubilization of coal into solubilized coal products and a cell-free bacterial byproduct useful for solubilizing coal. 5 tabs.

  15. SEAGRASS RHIZOSPHERE MICROBIAL COMMUNITIES

    Science.gov (United States)

    Devereux, Richard. 2005. Seagrass Rhizosphere Microbial Communities. In: Interactions Between Macro- and Microorganisms in Marine Sediments. E. Kristense, J.E. Kostka and R.H. Haese, Editors. American Geophysical Union, Washington, DC. p199-216. (ERL,GB 1213). Seagrasses ...

  16. The Occurrence of Bioactive Micromonosporae in Aquatic Habitats of the Sunshine Coast in Australia

    Directory of Open Access Journals (Sweden)

    D. Ipek Kurtböke

    2008-06-01

    Full Text Available Screening strategies based on the ecological knowledge of antibiotic producing microorganisms and their roles in the natural environment are being increasingly employed in the search for novel antibiotic agents. Micromonosporae are common inhabitants of aquatic habitats and have proved to be a continuing source of novel bioactive compounds including antibacterial and antitumor agents. The ecological distribution and frequency of bioactive micromonosporae in Sunshine Coast region aquatic habitats were studied through a range of selective isolation procedures designed to negatively select against the isolation of unwanted microbial taxa commonly associated with marine environments. It was revealed that bioactive compound producing species of micromonosporae were present in the aquatic habitats of the Sunshine Coast region in Australia.

  17. Measuring microbial metabolism in atypical environments: Bentonite in used nuclear fuel storage.

    Science.gov (United States)

    Stone, Wendy; Kroukamp, Otini; Moes, Ana; McKelvie, Jennifer; Korber, Darren R; Wolfaardt, Gideon M

    2016-01-01

    Genomics enjoys overwhelming popularity in the study of microbial ecology. However, extreme or atypical environments often limit the use of such well-established tools and consequently demand a novel approach. The bentonite clay matrix proposed for use in Deep Geological Repositories for the long-term storage of used nuclear fuel is one such challenging microbial habitat. Simple, accessible tools were developed for the study of microbial ecology and metabolic processes that occur within this habitat, since the understanding of the microbiota-niche interaction is fundamental to describing microbial impacts on engineered systems such as compacted bentonite barriers. Even when genomic tools are useful for the study of community composition, techniques to describe such microbial impacts and niche interactions should complement these. Tools optimised for assessing localised microbial activity within bentonite included: (a) the qualitative use of the resazurin-resorufin indicator system for redox localisation, (b) the use of a CaCl2 buffer for the localisation of pH, and (c) fluorometry for the localisation of precipitated sulphide. The use of the Carbon Dioxide Evolution Monitoring System was also validated for measuring microbial activity in desiccated and saturated bentonite. Finally, the buffering of highly-basic bentonite at neutral pH improved the success of isolation of microbial populations, but not DNA, from the bentonite matrix. Thus, accessible techniques were optimised for exploring microbial metabolism in the atypical environments of clay matrices and desiccated conditions. These tools have application to the applied field of used nuclear fuel management, as well as for examining the fundamental biogeochemical cycles active in sedimentary and deep geological environments. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Stream microbial diversity responds to environmental changes: Review and synthesis of existing research

    Directory of Open Access Journals (Sweden)

    Lydia eZeglin

    2015-05-01

    Full Text Available The importance of microbial activity to ecosystem function in aquatic ecosystems is well established, but microbial diversity has been less frequently addressed. This review and synthesis of the hundreds of published studies on stream microbial diversity shows that factors known to drive ecosystem processes, such as nutrient availability, hydrology, metal contamination, contrasting land-use and temperature, also cause heterogeneity in bacterial diversity. Temporal heterogeneity in stream bacterial diversity was frequently observed, reflecting the dynamic nature of both stream ecosystems and microbial community composition. However, within-stream spatial differences in stream bacterial diversity were more commonly observed, driven specifically by different organic matter compartments. Bacterial phyla showed similar patterns in relative abundance with regard to compartment type across different streams. For example, surface water contained the highest relative abundance of Actinobacteria, while epilithon contained the highest relative abundance of Cyanobacteria and Bacteroidetes. This suggests that contrasting physical and/or nutritional habitats characterized by different stream organic matter compartment types may select for certain bacterial lineages. When comparing the prevalence of physicochemical effects on stream bacterial diversity, effects of changing metal concentrations were most, while effects of differences in nutrient concentrations were least frequently observed. This may indicate that although changing nutrient concentrations do tend to affect microbial diversity, other environmental factors are more likely to alter stream microbial diversity and function. The common observation of connections between ecosystem process drivers and microbial diversity suggests that microbial taxonomic turnover could mediate ecosystem-scale responses to changing environmental conditions, including both microbial habitat distribution and

  19. Chapter 6. Landscape Analysis for Habitat Monitoring

    Science.gov (United States)

    Samuel A. Cushman; Kevin McGarigal; Kevin S. McKelvey; Christina D. Vojta; Claudia M. Regan

    2013-01-01

    The primary objective of this chapter is to describe standardized methods for measur¬ing and monitoring attributes of landscape pattern in support of habitat monitoring. This chapter describes the process of monitoring categorical landscape maps in which either selected habitat attributes or different classes of habitat quality are represented as different patch types...

  20. A technical guide for monitoring wildlife habitat

    Science.gov (United States)

    M.M. Rowland; C.D. Vojta

    2013-01-01

    Information about status and trend of wildlife habitat is important for the U.S. Department of Agriculture, Forest Service to accomplish its mission and meet its legal requirements. As the steward of 193 million acres (ac) of Federal land, the Forest Service needs to evaluate the status of wildlife habitat and how it compares with desired conditions. Habitat monitoring...

  1. Preparing for the crewed Mars journey: microbiota dynamics in the confined Mars500 habitat during simulated Mars flight and landing.

    Science.gov (United States)

    Schwendner, Petra; Mahnert, Alexander; Koskinen, Kaisa; Moissl-Eichinger, Christine; Barczyk, Simon; Wirth, Reinhard; Berg, Gabriele; Rettberg, Petra

    2017-10-04

    The Mars500 project was conceived as the first full duration simulation of a crewed return flight to Mars. For 520 days, six crew members lived confined in a specifically designed spacecraft mock-up. The herein described "MIcrobial ecology of Confined Habitats and humAn health" (MICHA) experiment was implemented to acquire comprehensive microbiota data from this unique, confined manned habitat, to retrieve important information on the occurring microbiota dynamics, the microbial load and diversity in the air and on various surfaces. In total, 360 samples from 20 (9 air, 11 surface) locations were taken at 18 time-points and processed by extensive cultivation, PhyloChip and next generation sequencing (NGS) of 16S rRNA gene amplicons. Cultivation assays revealed a Staphylococcus and Bacillus-dominated microbial community on various surfaces, with an average microbial load that did not exceed the allowed limits for ISS in-flight requirements indicating adequate maintenance of the facility. Areas with high human activity were identified as hotspots for microbial accumulation. Despite substantial fluctuation with respect to microbial diversity and abundance throughout the experiment, the location within the facility and the confinement duration were identified as factors significantly shaping the microbial diversity and composition, with the crew representing the main source for microbial dispersal. Opportunistic pathogens, stress-tolerant or potentially mobile element-bearing microorganisms were predicted to be prevalent throughout the confinement, while the overall microbial diversity dropped significantly over time. Our findings clearly indicate that under confined conditions, the community structure remains a highly dynamic system which adapts to the prevailing habitat and micro-conditions. Since a sterile environment is not achievable, these dynamics need to be monitored to avoid spreading of highly resistant or potentially pathogenic microorganisms and a

  2. Seasonal and interannual effects of hypoxia on fish habitat quality in central Lake Erie

    Science.gov (United States)

    Arend, Kristin K.; Beletsky, Dmitry; DePinto, Joseph; Ludsin, Stuart A.; Roberts, James J.; Rucinski, Daniel K.; Scavia, Donald; Schwab, David J.; Höök, Tomas O.

    2011-01-01

    1. Hypoxia occurs seasonally in many stratified coastal marine and freshwater ecosystems when bottom dissolved oxygen (DO) concentrations are depleted below 2–3 mg O2 L-1. 2. We evaluated the effects of hypoxia on fish habitat quality in the central basin of Lake Erie from 1987 to 2005, using bioenergetic growth rate potential (GRP) as a proxy for habitat quality. We compared the effect of hypoxia on habitat quality of (i) rainbow smelt, Osmerus mordax mordax Mitchill (young-of-year, YOY, and adult), a cold-water planktivore, (ii) emerald shiner, Notropis atherinoides Rafinesque (adult), a warm-water planktivore, (iii) yellow perch, Perca flavescens Mitchill (YOY and adult), a cool-water benthopelagic omnivore and (iv) round goby Neogobius melanostomus Pallas (adult) a eurythermal benthivore. Annual thermal and DO profiles were generated from 1D thermal and DO hydrodynamics models developed for Lake Erie’s central basin. 3. Hypoxia occurred annually, typically from mid-July to mid-October, which spatially and temporally overlaps with otherwise high benthic habitat quality. Hypoxia reduced the habitat quality across fish species and life stages, but the magnitude of the reduction varied both among and within species because of the differences in tolerance to low DO levels and warm-water temperatures. 4. Across years, trends in habitat quality mirrored trends in phosphorus concentration and water column oxygen demand in central Lake Erie. The per cent reduction in habitat quality owing to hypoxia was greatest for adult rainbow smelt and round goby (mean: -35%), followed by adult emerald shiner (mean: -12%), YOY rainbow smelt (mean: -10%) and YOY and adult yellow perch (mean: -8.5%). 5. Our results highlight the importance of differential spatiotemporally interactive effects of DO and temperature on relative fish habitat quality and quantity. These effects have the potential to influence the performance of individual fish species as well as population dynamics

  3. Universal human habitat. Basic principles

    OpenAIRE

    Stepanov Vyacheslav Konstantinovich; Starikov Aleksandr Sergeevich

    2012-01-01

    Standard Rules on the Equalization of Opportunities for Persons with Disabilities were adopted in 1993 by the United Nations. They have been valid since then. The number of disabled and elderly people is ever growing due to injuries, accidents, environmental problems, deterioration of health, population aging and demographic disorders. The term "universal habitat" reads as "universal design" worldwide. The concept of "universal design" was developed by Ronald Mace, American arc...

  4. Carpinteria salt marsh habitat polygons

    Science.gov (United States)

    Lafferty, Kevin D.; Dunham, Eleca J.; Mancini, Frank T.; Stewart, Tara E.; Hechinger, Ryan F.

    2017-01-01

    We identified five common habitat types in Carpinteria Salt Marsh: channels, pans (flats), marsh, salt flat and upland.  We then drew polygons around each habitat type identified from a registered and orthorectified aerial photograph and created a GIS shapefile. Polygons were ground-truthed in the field. From these habitat polygons, one can use GIS applications to estimate the area of each habitat type in this estuary. These data support the following publications: Kuris, Armand M., et al. "Ecosystem energetic implications of parasite and free-living biomass in three estuaries." Nature 454.7203 (2008): 515-518.Hechinger, Ryan F., Kevin D. Lafferty, Andy P. Dobson, James H. Brown, and Armand M. Kuris. "A common scaling rule for abundance, energetics, and production of parasitic and free-living species." Science 333, no. 6041 (2011): 445-448.Hechinger, Ryan F., Kevin D. Lafferty, John P. McLaughlin, Brian L. Fredensborg, Todd C. Huspeni, Julio Lorda, Parwant K. Sandhu et al. "Food webs including parasites, biomass, body sizes, and life stages for three California/Baja California estuaries." Ecology 92, no. 3 (2011): 791-791.Buck, J.C., Hechinger, R.F., Wood, A.C., Stewart, T.E., Kuris, A.M., and Lafferty, K.D., "Host density increases parasite recruitment but decreases host risk in a snail-trematode system." Manuscript submitted for publication. Lafferty, K.D., Stewart, T.E., and Hechinger, R.F. (in press). Bird distribution surveys at Carpinteria Salt Marsh, California USA, January 2012 to March 2013: U.S. Geological Survey data release, http://dx.doi.org/10.5066/F7F47M95. 

  5. Multifunction Habitat Workstation/OLED Development

    Science.gov (United States)

    Schumacher, Shawn; Salazar, George; Schmidt, Oron

    2013-01-01

    This paper gives a general outline of both a multifunction habitat workstation and the research put into an Organic Light Emitting Diode (OLED) device. It first covers the tests that the OLED device will go through to become flight ready along with reasoning. Guidelines for building an apparatus to house the display and its components are given next, with the build of such following. The three tests the OLED goes through are presented (EMI, Thermal/Vac, Radiation) along with the data recovered. The second project of a multifunction workstation is then discussed in the same pattern. Reasoning for building such a workstation with telepresence in mind is offered. Build guidelines are presented first, with the build timeline following. Building the workstation will then be shown in great detail along with accompanying photos. Once the workstation has been discussed, the versatility of its functions are given. The paper concludes with future views and concepts that can added when the time or technology presents itself.

  6. Spatiotemporal patterns and habitat associations of smallmouth bass (Micropterus dolomieu) invading salmon-rearing habitat

    Science.gov (United States)

    Lawrence, David J.; Olden, Julian D.; Torgersen, Christian E.

    2012-01-01

    km (2009 and 2010, respectively) as stream temperatures seasonally warmed, but subyearling Chinook salmon were also found farther upstream during this time.4. Our multiscale analysis suggests that bass were selecting habitat based on antecedent thermal history at a broad scale, and if satisfactory temperature conditions were met, mesoscale habitat features (i.e. channel-unit type and depth) played an additional role in determining bass abundance. The upstream extent of bass in the late summer corresponded to a high-gradient geomorphic discontinuity in the NFJDR, which probably hindered further upstream movements of bass. The habitat determinants and upstream extent of bass were largely consistent across years, despite marked differences in the magnitude and timing of spring peak flows prior to bass spawning.5. The overriding influence of water temperature on smallmouth bass distribution suggests that managers may be able limit future upstream range expansions of bass into salmon-rearing habitat by concentrating on restoration activities that mitigate climate- or land-use-related stream warming. These management activities could be prioritised to capitalise on survival bottlenecks in the life history of bass and spatially focused on landscape knick points such as high-gradient discontinuities to discourage further upstream movements of bass.

  7. Instream Physical Habitat Modelling Types

    DEFF Research Database (Denmark)

    Conallin, John; Boegh, Eva; Krogsgaard, Jørgen

    2010-01-01

    The introduction of the EU Water Framework Directive (WFD) is providing member state water resource managers with significant challenges in relation to meeting the deadline for 'Good Ecological Status' by 2015. Overall, instream physical habitat modelling approaches have advantages and disadvanta......The introduction of the EU Water Framework Directive (WFD) is providing member state water resource managers with significant challenges in relation to meeting the deadline for 'Good Ecological Status' by 2015. Overall, instream physical habitat modelling approaches have advantages...... physical habitat models. In parametric and non-parametric regression models, model assumptions are often not satisfied and the models are difficult to transfer to other regions. Research-based methods such as the artificial neural networks and individual-based modelling have promising potential as water......-friendly and have flexible data needs. They can easily be implemented in new regions using expert information or different types of local data. Furthermore, they are easily presentable to stakeholders and have the potential to be applied over large spatial scales. Integral care must be taken in the use...

  8. Alligator, Alligator mississippiensis, habitat suitability index model

    Science.gov (United States)

    Waddle, J. Hardin

    2017-01-01

    The 2012 Coastal Master Plan utilized Habitat Suitability Indices (HSIs) to evaluate potential project effects on wildlife species. Even though HSIs quantify habitat condition, which may not directly correlate to species abundance, they remain a practical and tractable way to assess changes in habitat quality from various restoration actions. As part of the legislatively mandated five year update to the 2012 plan, the wildlife habitat suitability indices were updated and revised using literature and existing field data where available. The outcome of these efforts resulted in improved, or in some cases entirely new suitability indices. This report describes the development of the habitat suitability indices for the American alligator, Alligator mississippiensis.

  9. Natural selection on thermal preference, critical thermal maxima and locomotor performance.

    Science.gov (United States)

    Gilbert, Anthony L; Miles, Donald B

    2017-08-16

    Climate change is resulting in a radical transformation of the thermal quality of habitats across the globe. Whereas species have altered their distributions to cope with changing environments, the evidence for adaptation in response to rising temperatures is limited. However, to determine the potential of adaptation in response to thermal variation, we need estimates of the magnitude and direction of natural selection on traits that are assumed to increase persistence in warmer environments. Most inferences regarding physiological adaptation are based on interspecific analyses, and those of selection on thermal traits are scarce. Here, we estimate natural selection on major thermal traits used to assess the vulnerability of ectothermic organisms to altered thermal niches. We detected significant directional selection favouring lizards with higher thermal preferences and faster sprint performance at their optimal temperature. Our analyses also revealed correlational selection between thermal preference and critical thermal maxima, where individuals that preferred warmer body temperatures with cooler critical thermal maxima were favoured by selection. Recent published estimates of heritability for thermal traits suggest that, in concert with the strong selective pressures we demonstrate here, evolutionary adaptation may promote long-term persistence of ectotherms in altered thermal environments. © 2017 The Author(s).

  10. REVIEW: Can habitat selection predict abundance?

    Science.gov (United States)

    Boyce, Mark S; Johnson, Chris J; Merrill, Evelyn H; Nielsen, Scott E; Solberg, Erling J; van Moorter, Bram

    2016-01-01

    Habitats have substantial influence on the distribution and abundance of animals. Animals' selective movement yields their habitat use. Animals generally are more abundant in habitats that are selected most strongly. Models of habitat selection can be used to distribute animals on the landscape or their distribution can be modelled based on data of habitat use, occupancy, intensity of use or counts of animals. When the population is at carrying capacity or in an ideal-free distribution, habitat selection and related metrics of habitat use can be used to estimate abundance. If the population is not at equilibrium, models have the flexibility to incorporate density into models of habitat selection; but abundance might be influenced by factors influencing fitness that are not directly related to habitat thereby compromising the use of habitat-based models for predicting population size. Scale and domain of the sampling frame, both in time and space, are crucial considerations limiting application of these models. Ultimately, identifying reliable models for predicting abundance from habitat data requires an understanding of the mechanisms underlying population regulation and limitation. © 2015 The Authors. Journal of Animal Ecology published by John Wiley & Sons Ltd on behalf of British Ecological Society.

  11. Global Microbial Identifier

    DEFF Research Database (Denmark)

    Wielinga, Peter; Hendriksen, Rene S.; Aarestrup, Frank Møller

    2017-01-01

    Human and animal populations are increasingly confronted with emerging and re-emerging infections and often such infections are exchanged between these populations, e.g. through food. A more effective and uniform approach to the prevention of these microbial threats is essential. The technological......-source systems. There is therefore an obvious need to develop a global system of whole microbial genome databases to aggregate, share, mine and use microbiological genomic data, to address global public health and clinical challenges, and most importantly to identify and diagnose infectious diseases. The global...... of microorganisms, for the identification of relevant genes and for the comparison of genomes to detect outbreaks and emerging pathogens. To harness the full potential of WGS, a shared global database of genomes linked to relevant metadata and the necessary software tools needs to be generated, hence the global...

  12. Microbial Risk Assessment

    Science.gov (United States)

    Ott, C. M.; Mena, K. D.; Nickerson, C.A.; Pierson, D. L.

    2009-01-01

    Historically, microbiological spaceflight requirements have been established in a subjective manner based upon expert opinion of both environmental and clinical monitoring results and the incidence of disease. The limited amount of data, especially from long-duration missions, has created very conservative requirements based primarily on the concentration of microorganisms. Periodic reevaluations of new data from later missions have allowed some relaxation of these stringent requirements. However, the requirements remain very conservative and subjective in nature, and the risk of crew illness due to infectious microorganisms is not well defined. The use of modeling techniques for microbial risk has been applied in the food and potable water industries and has exceptional potential for spaceflight applications. From a productivity standpoint, this type of modeling can (1) decrease unnecessary costs and resource usage and (2) prevent inadequate or inappropriate data for health assessment. In addition, a quantitative model has several advantages for risk management and communication. By identifying the variable components of the model and the knowledge associated with each component, this type of modeling can: (1) Systematically identify and close knowledge gaps, (2) Systematically identify acceptable and unacceptable risks, (3) Improve communication with stakeholders as to the reasons for resource use, and (4) Facilitate external scientific approval of the NASA requirements. The modeling of microbial risk involves the evaluation of several key factors including hazard identification, crew exposure assessment, dose-response assessment, and risk characterization. Many of these factors are similar to conditions found on Earth; however, the spaceflight environment is very specialized as the inhabitants live in a small, semi-closed environment that is often dependent on regenerative life support systems. To further complicate modeling efforts, microbial dose

  13. Pressure as an environmental parameter for microbial life--a review.

    Science.gov (United States)

    Picard, Aude; Daniel, Isabelle

    2013-12-15

    Microbial life has been prevailing in the biosphere for the last 3.8 Ga at least. Throughout most of the Earth's history it has experienced a range of pressures; both dynamic pressure when the young Earth was heavily bombarded, and static pressure in subsurface environments that could have served as a refuge and where microbial life nowadays flourishes. In this review, we discuss the extent of high-pressure habitats in early and modern times and provide a short overview of microbial survival under dynamic pressures. We summarize the current knowledge about the impact of microbial activity on biogeochemical cycles under pressures characteristic of the deep subsurface. We evaluate the possibility that pressure can be a limiting parameter for life at depth. Finally, we discuss the open questions and knowledge gaps that exist in the field of high-pressure geomicrobiology. © 2013 Elsevier B.V. All rights reserved.

  14. Vaccines and photodynamic therapies for oral microbial-related diseases.

    Science.gov (United States)

    Liu, Pei-Feng; Zhu, Wen-Hong; Huang, Chun-Ming

    2009-01-01

    The mouth is a favorable habitat for a great variety of bacteria. Microbial composition of dental plaque is the usual cause of various oral diseases in humans, including dental caries, periodontal disease and halitosis. In general, oral antibacterial agents such as antibiotics are commonly used to treat oral bacterial infection. Traditional periodontal surgery is painful and time-consuming. In addition, bacterial resistance and toxicity of antibiotics have become a global pandemic and unavoidable. Recently, vaccines for dental caries and periodontal disease have been developed and applied. Moreover, the use of photodynamic therapy has become an alternative to antibiotic drugs. The purpose of this article is to highlight the advantages of vaccine therapy and photodynamic therapy for oral microbial-related diseases compared to treatments with antimicrobial agents and traditional periodontal surgery.

  15. Vaccines and Photodynamic Therapies for Oral Microbial-Related Diseases

    Science.gov (United States)

    Liu, Pei-Feng; Zhu, Wen-Hong; Huang, Chun-Ming

    2009-01-01

    The mouth is a favorable habitat for a great variety of bacteria. Microbial composition of dental plaque is the usual cause of various oral diseases in humans, including dental caries, periodontal disease and halitosis. In general, oral antibacterial agents such as antibiotics are commonly used to treat oral bacterial infection. Traditional periodontal surgery is painful and time-consuming. In addition, bacterial resistance and toxicity of antibiotics have become a global pandemic and unavoidable. Recently, vaccines for dental caries and periodontal disease have been developed and applied. Moreover, the use of photodynamic therapy has become an alternative to antibiotic drugs. The purpose of this article is to highlight the advantages of vaccine therapy and photodynamic therapy for oral microbial-related diseases compared to treatments with antimicrobial agents and traditional periodontal surgery. PMID:19149517

  16. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year's report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  17. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Chisholm, J.L.

    1992-03-01

    The objective of this project is to perform a microbial enhanced oil recovery field pilot in the Southeast Vassar Vertz Sand Unit (SEVVSU) in Payne County, Oklahoma. Indigenous, anaerobic, nitrate reducing bacteria will be stimulated to selectively plug flow paths which have been referentially swept by a prior waterflood. This will force future flood water to invade bypassed regions of the reservoir and increase sweep efficiency. This report covers progress made during the second year, January 1, 1990 to December 31, 1990, of the Microbial Field Pilot Study project. Information on reservoir ecology, surface facilities design, operation of the unit, core experiments, modeling of microbial processes, and reservoir characterization and simulation are presented in the report. To better understand the ecology of the target reservoir, additional analyses of the fluids which support bacteriological growth and the microbiology of the reservoir were performed. The results of the produced and injected water analysis show increasing sulfide concentrations with respect to time. In March of 1990 Mesa Limited Partnership sold their interest in the SEVVSU to Sullivan and Company. In April, Sullivan and Company assumed operation of the field. The facilities for the field operation of the pilot were refined and implementation was begun. Core flood experiments conducted during the last year were used to help define possible mechanisms involved in microbial enhanced oil recovery. The experiments were performed at SEVVSU temperature using fluids and inoculum from the unit. The model described in last year`s report was further validated using results from a core flood experiment. The model was able to simulate the results of one of the core flood experiments with good quality.

  18. Thermal comfort

    DEFF Research Database (Denmark)

    d’Ambrosio Alfano, Francesca Romana; Olesen, Bjarne W.; Palella, Boris Igor

    2014-01-01

    Thermal comfort is one of the most important aspects of the indoor environmental quality due to its effects on well-being, people's performance and building energy requirements. Its attainment is not an easy task requiring advanced design and operation of building and HVAC systems, taking...... under specific conditions. At operation level, only few variables are taken into account with unpredictable effects on the assessment of comfort indices. In this paper, the main criteria for the design and assessment of thermal comfort are discussed in order to help building and HVAC systems designers...... into account all parameters involved. Even though thermal comfort fundamentals are consolidated topics for more than forty years, often designers seem to ignore or apply them in a wrong way. Design input values from standards are often considered as universal values rather than recommended values to be used...

  19. Pathogenesis of microbial keratitis.

    Science.gov (United States)

    Lakhundi, Sahreena; Siddiqui, Ruqaiyyah; Khan, Naveed Ahmed

    2017-03-01

    Microbial keratitis is a sight-threatening ocular infection caused by bacteria, fungi, and protist pathogens. Epithelial defects and injuries are key predisposing factors making the eye susceptible to corneal pathogens. Among bacterial pathogens, the most common agents responsible for keratitis include Staphylococcus aureus, Pseudomonas aeruginosa, Streptococcus pneumonia and Serratia species. Fungal agents of corneal infections include both filamentous as well as yeast, including Fusarium, Aspergillus, Phaeohyphomycetes, Curvularia, Paecilomyces, Scedosporium and Candida species, while in protists, Acanthamoeba spp. are responsible for causing ocular disease. Clinical features include redness, pain, tearing, blur vision and inflammation but symptoms vary depending on the causative agent. The underlying molecular mechanisms associated with microbial pathogenesis include virulence factors as well as the host factors that aid in the progression of keratitis, resulting in damage to the ocular tissue. The treatment therefore should focus not only on the elimination of the culprit but also on the neutralization of virulence factors to minimize the damage, in addition to repairing the damaged tissue. A complete understanding of the pathogenesis of microbial keratitis will lead to the rational development of therapeutic interventions. This is a timely review of our current understanding of the advances made in this field in a comprehensible manner. Coupled with the recently available genome sequence information and high throughput genomics technology, and the availability of innovative approaches, this will stimulate interest in this field. Copyright © 2017 Elsevier Ltd. All rights reserved.

  20. Microbial reduction of iodate

    Science.gov (United States)

    Councell, T.B.; Landa, E.R.; Lovley, D.R.

    1997-01-01

    The different oxidation species of iodine have markedly different sorption properties. Hence, changes in iodine redox states can greatly affect the mobility of iodine in the environment. Although a major microbial role has been suggested in the past to account for these redox changes, little has been done to elucidate the responsible microorganisms or the mechanisms involved. In the work presented here, direct microbial reduction of iodate was demonstrated with anaerobic cell suspensions of the sulfate reducing bacterium Desulfovibrio desulfuricans which reduced 96% of an initial 100 ??M iodate to iodide at pH 7 in 30 mM NaHCO3 buffer, whereas anaerobic cell suspensions of the dissimilatory Fe(III)-reducing bacterium Shewanella putrefaciens were unable to reduce iodate in 30 mM NaHCO3 buffer (pH 7). Both D. desulfuricans and S. putrefaciens were able to reduce iodate at pH 7 in 10 mM HEPES buffer. Both soluble ferrous iron and sulfide, as well as iron monosulfide (FeS) were shown to abiologically reduce iodate to iodide. These results indicate that ferric iron and/or sulfate reducing bacteria are capable of mediating both direct, enzymatic, as well as abiotic reduction of iodate in natural anaerobic environments. These microbially mediated reactions may be important factors in the fate and transport of 129I in natural systems.

  1. Composition and Functional Specialists of the Gut Microbiota of Frogs Reflect Habitat Differences and Agricultural Activity.

    Science.gov (United States)

    Huang, Bing-Hong; Chang, Chun-Wen; Huang, Chih-Wei; Gao, Jian; Liao, Pei-Chun

    2017-01-01

    The physiological impact of agricultural pollution, habitat disturbance, and food source variability on amphibian remains poorly understood. By comparing the composition and predicted functions of gut microbiota of two frog species from forest and farmland, we quantified the effects of the exogenous environment and endogenous filters on gut microbiota and the corresponding functions. However, compositional differences of the gut microbiota between the frog species were not detected, even when removing roughly 80-88% of the confounding effect produced by common and shared bacteria (i.e., generalists) and those taxa deemed too rare. The habitat effect accounted for 14.1% of the compositional difference of gut microbial specialists, but host and host × habitat effects were not significant. Similar trends of a significant habitat effect, at an even higher level (26.0%), for the physiological and metabolic functions of gut microbiota was predicted. A very obvious skewing of the relative abundance of functional groups toward farmland habitats reflects the highly diverse bacterial functions of farmland frogs, in particular related to pathogenic disease and pesticide degradation, which may be indication of poor adaptation or strong selective pressure against disease. These patterns reflect the impacts of agricultural activities on frogs and how such stresses may be applied in an unequal manner for different frog species.

  2. Composition and Functional Specialists of the Gut Microbiota of Frogs Reflect Habitat Differences and Agricultural Activity

    Directory of Open Access Journals (Sweden)

    Bing-Hong Huang

    2018-01-01

    Full Text Available The physiological impact of agricultural pollution, habitat disturbance, and food source variability on amphibian remains poorly understood. By comparing the composition and predicted functions of gut microbiota of two frog species from forest and farmland, we quantified the effects of the exogenous environment and endogenous filters on gut microbiota and the corresponding functions. However, compositional differences of the gut microbiota between the frog species were not detected, even when removing roughly 80–88% of the confounding effect produced by common and shared bacteria (i.e., generalists and those taxa deemed too rare. The habitat effect accounted for 14.1% of the compositional difference of gut microbial specialists, but host and host × habitat effects were not significant. Similar trends of a significant habitat effect, at an even higher level (26.0%, for the physiological and metabolic functions of gut microbiota was predicted. A very obvious skewing of the relative abundance of functional groups toward farmland habitats reflects the highly diverse bacterial functions of farmland frogs, in particular related to pathogenic disease and pesticide degradation, which may be indication of poor adaptation or strong selective pressure against disease. These patterns reflect the impacts of agricultural activities on frogs and how such stresses may be applied in an unequal manner for different frog species.

  3. Thermal defoliation

    Science.gov (United States)

    The negative perception some consumers hold regarding agricultural chemicals has resulted in an increased demand for organic foods and fibers, and in increasing political pressure for the regulation of agricultural production practices. This has revived interest in thermal defoliation of cotton and ...

  4. Holographic thermalization

    NARCIS (Netherlands)

    Balasubramanian, V.; Bernamonti, A.; de Boer, J.; Copland, N.; Craps, B.; Keski-Vakkuri, E.; Müller, B.; Schäfer, A.; Shigemori, M.; Staessens, W.

    2011-01-01

    Using the AdS/CFT correspondence, we probe the scale-dependence of thermalization in strongly coupled field theories following a quench, via calculations of two-point functions, Wilson loops and entanglement entropy in d=2,3,4. In the saddlepoint approximation these probes are computed in AdS space

  5. Competition and niche separation of pelagic bacteria in freshwater habitats.

    Science.gov (United States)

    Pernthaler, Jakob

    2017-06-01

    Freshwater bacterioplankton assemblages are composed of sympatric populations that can be delineated, for example, by ribosomal RNA gene relatedness and that differ in key ecophysiological properties. They may be free-living or attached, specialized for particular concentrations or subsets of substrates, or invest a variable amount of their resources in defence traits against protistan predators and viruses. Some may be motile and tactic whereas others are not, with far-reaching implications for their respective life styles and niche partitioning. The co-occurrence of competitors with overlapping growth requirements has profound consequences for the stability of community functions; it can to some extent be explained by habitat factors such as the microscale complexity and spatiotemporal variability of the lacustrine environments. On the other hand, the composition and diversity of freshwater microbial assemblages also reflects non-equilibrium states, dispersal and the stochasticity of community assembly processes. This review synoptically discusses the competition and niche separation of heterotrophic bacterial populations (defined at various levels of phylogenetic resolution) in the pelagic zone of inland surface waters from a variety of angles, focusing on habitat heterogeneity and the resulting biogeographic distribution patterns, the ecophysiological adaptations to the substrate field and the interactions of prokaryotes with predators and viruses. © 2017 Society for Applied Microbiology and John Wiley & Sons Ltd.

  6. Caenorhabditis elegans responses to bacteria from its natural habitats

    Science.gov (United States)

    Rowedder, Holli; Braendle, Christian; Félix, Marie-Anne; Ruvkun, Gary

    2016-01-01

    Most Caenorhabditis elegans studies have used laboratory Escherichia coli as diet and microbial environment. Here we characterize bacteria of C. elegans' natural habitats of rotting fruits and vegetation to provide greater context for its physiological responses. By the use of 16S ribosomal DNA (rDNA)-based sequencing, we identified a large variety of bacteria in C. elegans habitats, with phyla Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria being most abundant. From laboratory assays using isolated natural bacteria, C. elegans is able to forage on most bacteria (robust growth on ∼80% of >550 isolates), although ∼20% also impaired growth and arrested and/or stressed animals. Bacterial community composition can predict wild C. elegans population states in both rotting apples and reconstructed microbiomes: alpha-Proteobacteria-rich communities promote proliferation, whereas Bacteroidetes or pathogens correlate with nonproliferating dauers. Combinatorial mixtures of detrimental and beneficial bacteria indicate that bacterial influence is not simply nutritional. Together, these studies provide a foundation for interrogating how bacteria naturally influence C. elegans physiology. PMID:27317746

  7. Thermal Hardware for the Thermal Analyst

    Science.gov (United States)

    Steinfeld, David

    2015-01-01

    The presentation will be given at the 26th Annual Thermal Fluids Analysis Workshop (TFAWS 2015) hosted by the Goddard Space Flight Center (GSFC) Thermal Engineering Branch (Code 545). NCTS 21070-1. Most Thermal analysts do not have a good background into the hardware which thermally controls the spacecraft they design. SINDA and Thermal Desktop models are nice, but knowing how this applies to the actual thermal hardware (heaters, thermostats, thermistors, MLI blanketing, optical coatings, etc...) is just as important. The course will delve into the thermal hardware and their application techniques on actual spacecraft. Knowledge of how thermal hardware is used and applied will make a thermal analyst a better engineer.

  8. Spatially extensive microbial biogeography of the Indian Ocean provides insights into the unique community structure of a pristine coral atoll

    DEFF Research Database (Denmark)

    Jeffries, Thomas C; Ostrowski, Martin; Williams, Rohan B

    2015-01-01

    Microorganisms act both as drivers and indicators of perturbations in the marine environment. In an effort to establish baselines to predict the response of marine habitats to environmental change, here we report a broad survey of microbial diversity across the Indian Ocean, including the first m...

  9. Microbial Cell Dynamics Lab (MCDL)

    Data.gov (United States)

    Federal Laboratory Consortium — The Microbial Cell Dynamics Laboratory at PNNL enables scientists to study the molecular details of microbes under relevant environmental conditions. The MCDL seeks...

  10. Oligotyping reveals community level habitat selection within the genus Vibrio

    Directory of Open Access Journals (Sweden)

    Victor Thomas Schmidt

    2014-11-01

    Full Text Available The genus Vibrio is a metabolically and genetically diverse group of facultative anaerobic Bacteria, common in aquatic environments and marine hosts. The genus contains several species of importance to human health and aquaculture, including the causative agents of human cholera and fish vibriosis. Vibrios display a wide variety of known life histories, from opportunistic pathogens to long-standing symbioses with individual host species. Studying Vibrio ecology has been challenging as individual species often display a wide range of habitat preferences, and groups of vibrios can act as socially cohesive groups. Although strong associations with salinity, temperature and other environmental variables have been established, the degree of habitat or host specificity at both the individual and community levels is unknown. Here we use oligotyping analyses in combination with a large collection of existing Vibrio 16S ribosomal RNA (rRNA gene sequence data to reveal patterns of Vibrio ecology across a wide range of environmental, host, and abiotic substrate associated habitats. Our data show that individual taxa often display a wide range of habitat preferences yet tend to be highly abundant in either substrate-associated or free-living environments. Our analyses show that Vibrio communities share considerable overlap between two distinct hosts (i.e., sponge and fish yet are distinct from the abiotic plastic substrates. Lastly, evidence for habitat specificity at the community level exists in some habitats, despite considerable stochasticity in others. In addition to providing insights into Vibrio ecology across a broad range of habitats, our study shows the utility of oligotyping as a facile, high-throughput and unbiased method for large scale analyses of publicly available sequence data repositories and suggests its wide application could greatly extend the range of possibilities to explore microbial ecology.

  11. Reactivation of Deep Subsurface Microbial Community in Response to Methane or Methanol Amendment

    Science.gov (United States)

    Rajala, Pauliina; Bomberg, Malin

    2017-01-01

    Microbial communities in deep subsurface environments comprise a large portion of Earth’s biomass, but the microbial activity in these habitats is largely unknown. Here, we studied how microorganisms from two isolated groundwater fractures at 180 and 500 m depths of the Outokumpu Deep Drillhole (Finland) responded to methane or methanol amendment, in the presence or absence of sulfate as an additional electron acceptor. Methane is a plausible intermediate in the deep subsurface carbon cycle, and electron acceptors such as sulfate are critical components for oxidation processes. In fact, the majority of the available carbon in the Outokumpu deep biosphere is present as methane. Methanol is an intermediate of methane oxidation, but may also be produced through degradation of organic matter. The fracture fluid samples were incubated in vitro with methane or methanol in the presence or absence of sulfate as electron acceptor. The metabolic response of microbial communities was measured by staining the microbial cells with fluorescent redox sensitive dye combined with flow cytometry, and DNA or cDNA-derived amplicon sequencing. The microbial community of the fracture zone at the 180 m depth was originally considerably more respiratory active and 10-fold more numerous (105 cells ml-1 at 180 m depth and 104 cells ml-1 at 500 m depth) than the community of the fracture zone at the 500 m. However, the dormant microbial community at the 500 m depth rapidly reactivated their transcription and respiration systems in the presence of methane or methanol, whereas in the shallower fracture zone only a small sub-population was able to utilize the newly available carbon source. In addition, the composition of substrate activated microbial communities differed at both depths from original microbial communities. The results demonstrate that OTUs representing minor groups of the total microbial communities play an important role when microbial communities face changes in

  12. Plasmonic cell nanocoating: a new concept for rapid microbial screening.

    Science.gov (United States)

    Xu, Ke; Bui, Minh-Phuong N; Fang, Aiqin; Abbas, Abdennour

    2017-11-01

    Nanocoating of single microbial cells with gold nanostructures can confer optical, electrical, thermal, and mechanical properties to microorganisms, thus enabling new avenues for their control, study, application, and detection. Cell nanocoating is often performed using layer-by-layer (LbL) deposition. LbL is time-consuming and relies on nonspecific electrostatic interactions, which limit potential applications for microbial diagnostics. Here, we show that, by taking advantage of surface molecules densely present in the microbial outer layers, cell nanocoating with gold nanoparticles can be achieved within seconds using surface molecules, including disulfide- bond-containing (Dsbc) proteins and chitin. A simple activation of these markers and their subsequent interaction with gold nanoparticles allow specific microbial screening and quantification of bacteria and fungi within 5 and 30 min, respectively. The use of plasmonics and fluorescence as transduction methods offers a limit of detection below 35 cfu mL-1 for E. coli bacteria and 1500 cfu mL-1 for M. circinelloides fungi using a hand-held fluorescent reader. Graphical abstract A new concept for rapid microbial screening by targeting disulfide - bond-containing (Dsbc) proteins and chitin with reducing agents and gold nanoparticles.

  13. Detection of microbial Life in the Subsurface

    Science.gov (United States)

    Stan-Lotter, H.; Fendrihan, S.; Dornmayr-Pfaffenhuemer, M.; Legat, A.; Gruber, C.; Weidler, G.; Gerbl, F.

    2007-08-01

    In recent years microbial communities were detected, which dwell in rocks, soil and caves deep below the surface of the Earth. This has led to a new view of the diversity of the terrestrial biosphere and of the physico-chemical boundaries for life. Two types of subterranean environments are Permo-Triassic salt sediments and thermal radioactive springs from igneous rocks in the Alps. Viable extremely halophilic archaea were isolated from ancient salt sediments which are estimated to be about 250 million years old (1). Chemotaxonomic and molecular characterization showed that they represent novel species, e. g. Halococcus salifodinae, Hcc. dombrowskiiand Halobacterium noricense. Simulation experiments with artificial halite suggested that these microorganisms probably survived while embedded in fluid inclusions. In the thermal springs, evidence for numerous novel microorganisms was found by 16S rDNA sequencing and probing for some metabolic genes; in addition, scanning electron microscopy of biofilms on the rock surfaces revealed great diversity of morphotypes (2). These communities appear to be active and growing, although their energy and carbon sources are entirely unknown. The characterization of subsurface inhabitants is of astrobiological relevance since extraterrestrial halite has been detected (3) and since microbial life on Mars, if existent, may have retreated into the subsurface. As a long-term goal, a thorough census of terrestrial microorganisms should be taken and their survival potential be determined in view of future missions for the search for extraterrestrial life, including planning precautions against possible forward contamination by space probes. (1) Fendrihan, S., Legat, A., Gruber, C., Pfaffenhuemer, M., Weidler, G., Gerbl, F., Stan-Lotter, H. (2006) Extremely halophilic archaea and the issue of long term microbial survival. Reviews in Environmental Science and Bio/technology 5, 1569-1605. (2) Weidler, G.W., Dornmayr-Pfaffenhuemer, M., Gerbl

  14. Microbial field pilot study

    Energy Technology Data Exchange (ETDEWEB)

    Knapp, R.M.; McInerney, M.J.; Menzie, D.E.; Coates, J.D.; Chisholm, J.L.

    1993-05-01

    A multi-well microbially enhanced oil recovery field pilot has been performed in the Southeast Vassar Vertz Sand Unit in Payne County, Oklahoma. The primary emphasis of the experiment was preferential plugging of high permeability zones for the purpose of improving waterflood sweep efficiency. Studies were performed to determine reservoir chemistry, ecology, and indigenous bacteria populations. Growth experiments were used to select a nutrient system compatible with the reservoir that encouraged growth of a group of indigenous nitrate-using bacteria and inhibit growth of sulfate-reducing bacteria. A specific field pilot area behind an active line drive waterflood was selected. Surface facilities were designed and installed. Injection protocols of bulk nutrient materials were prepared to facilitate uniform distribution of nutrients within the pilot area. By the end of December, 1991, 82.5 tons (75.0 tonnes) of nutrients had been injected in the field. A tracer test identified significant heterogeneity in the SEVVSU and made it necessary to monitor additional production wells in the field. The tracer tests and changes in production behavior indicate the additional production wells monitored during the field trial were also affected. Eighty two and one half barrels (13.1 m[sup 3]) of tertiary oil have been recovered. Microbial activity has increased CO[sub 2] content as indicated by increased alkalinity. A temporary rise in sulfide concentration was experienced. These indicate an active microbial community was generated in the field by the nutrient injection. Pilot area interwell pressure interference test results showed that significant permeability reduction occurred. The interwell permeabilities in the pilot area between the injector and the three pilot production wells were made more uniform which indicates a successful preferential plugging enhanced oil recovery project.

  15. Effects of temperature, soil substrate, and microbial community on carbon mineralization across three climatically contrasting forest sites.

    Science.gov (United States)

    Tang, Zuoxin; Sun, Xiaolu; Luo, Zhongkui; He, Nianpeng; Sun, Osbert Jianxin

    2018-01-01

    How biotic and abiotic factors influence soil carbon (C) mineralization rate (RS) has recently emerged as one of the focal interests in ecological studies. To determine the relative effects of temperature, soil substrate and microbial community on Rs, we conducted a laboratory experiment involving reciprocal microbial inoculations of three zonal forest soils, and measured RS over a 61-day period at three temperatures (5, 15, and 25°C). Results show that both Rs and the cumulative emission of C (Rcum), normalized to per unit soil organic C (SOC), were significantly affected by incubation temperature, soil substrate, microbial inoculum treatment, and their interactions (p soil substrate, microbial inoculum treatment, and their interaction all significantly affected both Rs (p soil substrate was much stronger than others. There was no consistent pattern of thermal adaptation in microbial decomposition of SOC in the reciprocal inoculations. Moreover, when different sources of microbial inocula were introduced to the same soil substrate, the microbial community structure converged with incubation without altering the overall soil enzyme activities; when different types of soil substrate were inoculated with the same sources of microbial inocula, both the microbial community structure and soil enzyme activities diverged. Overall, temperature plays a predominant role in affecting Rs and Rcum, while soil substrate determines the mineralizable SOC under given conditions. The role of microbial community in driving SOC mineralization is weaker than that of climate and soil substrate, because soil microbial community is both affected, and adapts to, climatic factors and soil matrix.

  16. Design and logistics of integrated spacecraft/lander lunar habitat concepts

    Science.gov (United States)

    Hypes, Warren D.; Wright, Robert L.; Gould, Marston J.; Lovelace, U. M.

    1991-01-01

    Integrated spacecraft/lander combinations have been designed to provide a support structure for thermal and galactic radiation shielding for three initial lunar habitat concepts. Integrating the support structure with the habitat reduces the logistics requirements for the implantation of the initial base. The designs are simple, make use of existing technologies, and minimize the amount of lunar surface preparation and crew activity. The design facilitates continued use of all elements in the development of a permanent lunar base and precludes the need for an entirely different structure of larger volume and increased complexity of implantation. This design philosophy, coupled with the reduced logistics, increases overall cost effectiveness.

  17. Microbial larvicides for malaria control in The Gambia

    Directory of Open Access Journals (Sweden)

    Green Clare

    2007-06-01

    Full Text Available Abstract Background Mosquito larval control may prove to be an effective tool for incorporating into integrated vector management (IVM strategies for reducing malaria transmission. Here the efficacy of microbial larvicides against Anopheles gambiae s.l. was tested in preparation for a large-scale larviciding programme in The Gambia. Methods The impact of water-dispersible (WDG and corn granule (CG formulations of commercial Bacillus sphaericus strain 2362 (Bs; VectoLex® and Bacillus thuringiensis var.israelensis strain AM65-52 (Bti; VectoBac® on larval development were tested under laboratory and field conditions to (1 identify the susceptibility of local vectors, (2 evaluate the residual effect and re-treatment intervals, (3 test the effectiveness of the microbials under operational application conditions and (4 develop a method for large-scale application. Results The major malaria vectors were highly susceptible to both microbials. The lethal concentration (LC to kill 95% of third instar larvae of Anopheles gambiae s.s. after 24 hours was 0.023 mg/l (14.9 BsITU/l for Bs WDG and 0.132 mg/l (396 ITU/l for Bti WDG. In general Bs had little residual effect under field conditions even when the application rate was 200 times greater than the LC95. However, there was a residual effect up to 10 days in standardized field tests implemented during the dry season. Both microbials achieved 100% mortality of larvae 24–48 hours post-application but late instar larvae were detected 4 days after treatment. Pupae development was reduced by 94% (95% Confidence Interval = 90.8–97.5% at weekly re-treatment intervals. Field tests showed that Bs had no residual activity against anopheline larvae. Both microbials provided complete protection when applied weekly. The basic training of personnel in identification of habitats, calibration of application equipment and active larviciding proved to be successful and achieved full coverage and control of mosquito

  18. Versatility of microbial transglutaminase.

    Science.gov (United States)

    Strop, Pavel

    2014-05-21

    Although microbial transglutaminases (mTGs) were initially discovered to offset the cost of producing mammalian transglutaminases for food applications, they have quickly become important tools in research and biotechnology. Today, mTGs are utilized for a large number of applications to conjugate proteins and peptides to small molecules, polymers, surfaces, and DNA, as well as to other proteins. It is important to know how to maximize the advantages of the enzymatic approach and avoid undesired cross-linking. This review focuses on the versatility of transglutaminases in the field of bioconjugation and covers recent developments in utilizing mTG for generating antibody drug conjugates (ADCs) for therapeutic applications.

  19. Influence of prevailing disturbances on soil biology and biochemistry of montane habitats at Nanda Devi Biosphere Reserve, India during wet and dry seasons

    DEFF Research Database (Denmark)

    Singh, S.K.; Singh, Anoop; Rai, J.P.N.

    2011-01-01

    The impact of prevailing disturbances in montane habitats of Nanda Devi Biosphere Reserve (NDBR) was studied on soil microbial population, biomass, soil respiration and enzyme activities during wet and dry seasons. The physico-chemical characteristics of soils exhibited conspicuous variation in t...

  20. Microbial bebop: creating music from complex dynamics in microbial ecology.

    Science.gov (United States)

    Larsen, Peter; Gilbert, Jack

    2013-01-01

    In order for society to make effective policy decisions on complex and far-reaching subjects, such as appropriate responses to global climate change, scientists must effectively communicate complex results to the non-scientifically specialized public. However, there are few ways however to transform highly complicated scientific data into formats that are engaging to the general community. Taking inspiration from patterns observed in nature and from some of the principles of jazz bebop improvisation, we have generated Microbial Bebop, a method by which microbial environmental data are transformed into music. Microbial Bebop uses meter, pitch, duration, and harmony to highlight the relationships between multiple data types in complex biological datasets. We use a comprehensive microbial ecology, time course dataset collected at the L4 marine monitoring station in the Western English Channel as an example of microbial ecological data that can be transformed into music. Four compositions were generated (www.bio.anl.gov/MicrobialBebop.htm.) from L4 Station data using Microbial Bebop. Each composition, though deriving from the same dataset, is created to highlight different relationships between environmental conditions and microbial community structure. The approach presented here can be applied to a wide variety of complex biological datasets.

  1. Differences in lateral gene transfer in hypersaline versus thermal environments

    Directory of Open Access Journals (Sweden)

    House Christopher H

    2011-07-01

    Full Text Available Abstract Background The role of lateral gene transfer (LGT in the evolution of microorganisms is only beginning to be understood. While most LGT events occur between closely related individuals, inter-phylum and inter-domain LGT events are not uncommon. These distant transfer events offer potentially greater fitness advantages and it is for this reason that these "long distance" LGT events may have significantly impacted the evolution of microbes. One mechanism driving distant LGT events is microbial transformation. Theoretically, transformative events can occur between any two species provided that the DNA of one enters the habitat of the other. Two categories of microorganisms that are well-known for LGT are the thermophiles and halophiles. Results We identified potential inter-class LGT events into both a thermophilic class of Archaea (Thermoprotei and a halophilic class of Archaea (Halobacteria. We then categorized these LGT genes as originating in thermophiles and halophiles respectively. While more than 68% of transfer events into Thermoprotei taxa originated in other thermophiles, less than 11% of transfer events into Halobacteria taxa originated in other halophiles. Conclusions Our results suggest that there is a fundamental difference between LGT in thermophiles and halophiles. We theorize that the difference lies in the different natures of the environments. While DNA degrades rapidly in thermal environments due to temperature-driven denaturization, hypersaline environments are adept at preserving DNA. Furthermore, most hypersaline environments, as topographical minima, are natural collectors of cellular debris. Thus halophiles would in theory be exposed to a greater diversity and quantity of extracellular DNA than thermophiles.

  2. Thermal Clothing

    Science.gov (United States)

    1997-01-01

    Gateway Technologies, Inc. is marketing and developing textile insulation technology originally developed by Triangle Research and Development Corporation. The enhanced thermal insulation stems from Small Business Innovation Research contracts from NASA's Johnson Space Center and the U.S. Air Force. The effectiveness of the insulation comes from the microencapsulated phase-change materials originally made to keep astronauts gloved hands warm. The applications for the product range from outer wear, housing insulation, and blankets to protective firefighting gear and scuba diving suits. Gateway has developed and begun marketing thermal regulating products under the trademark, OUTLAST. Products made from OUTLAST are already on the market, including boot and shoe liners, winter headgear, hats and caps for hunting and other outdoor sports, and a variety of men's and women's ski gloves.

  3. Turbulent Thermalization

    CERN Document Server

    Micha, Raphael; Micha, Raphael; Tkachev, Igor I.

    2004-01-01

    We study, analytically and with lattice simulations, the decay of coherent field oscillations and the subsequent thermalization of the resulting stochastic classical wave-field. The problem of reheating of the Universe after inflation constitutes our prime motivation and application of the results. We identify three different stages of these processes. During the initial stage of ``parametric resonance'', only a small fraction of the initial inflaton energy is transferred to fluctuations in the physically relevant case of sufficiently large couplings. A major fraction is transfered in the prompt regime of driven turbulence. The subsequent long stage of thermalization classifies as free turbulence. During the turbulent stages, the evolution of particle distribution functions is self-similar. We show that wave kinetic theory successfully describes the late stages of our lattice calculation. Our analytical results are general and give estimates of reheating time and temperature in terms of coupling constants and...

  4. Fuzzy modelling of Atlantic salmon physical habitat

    Science.gov (United States)

    St-Hilaire, André; Mocq, Julien; Cunjak, Richard

    2015-04-01

    Fish habitat models typically attempt to quantify the amount of available river habitat for a given fish species for various flow and hydraulic conditions. To achieve this, information on the preferred range of values of key physical habitat variables (e.g. water level, velocity, substrate diameter) for the targeted fishs pecies need to be modelled. In this context, we developed several habitat suitability indices sets for three Atlantic salmon life stages (young-of-the-year (YOY), parr, spawning adults) with the help of fuzzy logic modeling. Using the knowledge of twenty-seven experts, from both sides of the Atlantic Ocean, we defined fuzzy sets of four variables (depth, substrate size, velocity and Habitat Suitability Index, or HSI) and associated fuzzy rules. When applied to the Romaine River (Canada), median curves of standardized Weighted Usable Area (WUA) were calculated and a confidence interval was obtained by bootstrap resampling. Despite the large range of WUA covered by the expert WUA curves, confidence intervals were relatively narrow: an average width of 0.095 (on a scale of 0 to 1) for spawning habitat, 0.155 for parr rearing habitat and 0.160 for YOY rearing habitat. When considering an environmental flow value corresponding to 90% of the maximum reached by WUA curve, results seem acceptable for the Romaine River. Generally, this proposed fuzzy logic method seems suitable to model habitat availability for the three life stages, while also providing an estimate of uncertainty in salmon preferences.

  5. Expandable/Foldable Structures for Habitat Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Folded Structures Company (FSC) has developed an innovative design approach for multi-laminate, primary and secondary structures for planetary habitats that...

  6. Habitat Ecology Visual Surveys of Demersal Fishes and Habitats off California

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Since 1992, the Habitat Ecology team has been conducting fishery independent, visual surveys of demersal fishes and associated habitats in deep water (20 to 900...

  7. Two-dimensional physical habitat modeling of effects of habitat structures on urban stream restoration

    Directory of Open Access Journals (Sweden)

    Dongkyun IM

    2011-12-01

    Full Text Available River corridors, even if highly modified or degraded, still provide important habitats for numerous biological species, and carry high aesthetic and economic values. One of the keys to urban stream restoration is recovery and maintenance of ecological flows sufficient to sustain aquatic ecosystems. In this study, the Hongje Stream in the Seoul metropolitan area of Korea was selected for evaluating a physically-based habitat with and without habitat structures. The potential value of the aquatic habitat was evaluated by a weighted usable area (WUA using River2D, a two-dimensional hydraulic model. The habitat suitability for Zacco platypus in the Hongje Stream was simulated with and without habitat structures. The computed WUA values for the boulder, spur dike, and riffle increased by about 2%, 7%, and 131%, respectively, after their construction. Also, the three habitat structures, especially the riffle, can contribute to increasing hydraulic heterogeneity and enhancing habitat diversity.

  8. Effects of Actinomycete Secondary Metabolites on Sediment Microbial Communities.

    Science.gov (United States)

    Patin, Nastassia V; Schorn, Michelle; Aguinaldo, Kristen; Lincecum, Tommie; Moore, Bradley S; Jensen, Paul R

    2017-02-15

    Marine sediments harbor complex microbial communities that remain poorly studied relative to other biomes such as seawater. Moreover, bacteria in these communities produce antibiotics and other bioactive secondary metabolites, yet little is known about how these compounds affect microbial community structure. In this study, we used next-generation amplicon sequencing to assess native microbial community composition in shallow tropical marine sediments. The results revealed complex communities comprised of largely uncultured taxa, with considerable spatial heterogeneity and known antibiotic producers comprising only a small fraction of the total diversity. Organic extracts from cultured strains of the sediment-dwelling actinomycete genus Salinispora were then used in mesocosm studies to address how secondary metabolites shape sediment community composition. We identified predatory bacteria and other taxa that were consistently reduced in the extract-treated mesocosms, suggesting that they may be the targets of allelopathic interactions. We tested related taxa for extract sensitivity and found general agreement with the culture-independent results. Conversely, several taxa were enriched in the extract-treated mesocosms, suggesting that some bacteria benefited from the interactions. The results provide evidence that bacterial secondary metabolites can have complex and significant effects on sediment microbial communities. Ocean sediments represent one of Earth's largest and most poorly studied biomes. These habitats are characterized by complex microbial communities where competition for space and nutrients can be intense. This study addressed the hypothesis that secondary metabolites produced by the sediment-inhabiting actinomycete Salinispora arenicola affect community composition and thus mediate interactions among competing microbes. Next-generation amplicon sequencing of mesocosm experiments revealed complex communities that shifted following exposure to S

  9. [Microbial sources of pigments].

    Science.gov (United States)

    Cañizares-Villanueva, R O; Ríos-Leal, E; Olvera Ramírez, R; Ponce Noyola, T; Márquez Rocha, F

    1998-01-01

    Pigments from natural sources has been obtained since long time ago, and their interest has increased due to the toxicity problems caused by those of synthetic origin. In this way the pigments from microbial sources are a good alternative. Some of more important natural pigments, are the carotenoids, flavonoids (anthocyanins) and some tetrapirroles (chloropyls, phycobilliproteins). Another group less important are the betalains and quinones. The carotenoids are molecules formed by isoprenoids units and the most important used as colorant are the alpha and beta carotene which are precursors of vitamin A, and some xantophylls as astaxanthin. The pigment more used in the industry is the beta-carotene which is obtained from some microalgae and cyanobacteria. The astaxanthin another important carotenoid is a red pigment of great commercial value, and it is used in the pharmaceutical feed and acuaculture industries. This pigments is mainly obtained from Phaffia rhodozyma and Haematococcus pluvialis and other organisms. The phycobilliproteins obtained from cyanobacteria and some group of algae, have recently been increased on the food industries. In the last years it has been used as fluorescent marker in biochemical assays. Our research group have carried out studies about the factors that improve the production of these pigments obtained from different microbial species as well as the methods for their extraction and application.

  10. Compositions of constructed microbial mats

    Science.gov (United States)

    Bender, Judith A.; Phillips, Peter C.

    1999-01-01

    Compositions and methods of use of constructed microbial mats, comprising cyanobacteria and purple autotrophic bacteria and an organic nutrient source, in a laminated structure, are described. The constructed microbial mat is used for bioremediation of different individual contaminants and for mixed or multiple contaminants, and for production of beneficial compositions and molecules.

  11. A microbial world within us

    NARCIS (Netherlands)

    Zoetendal, E.G.; Vaughan, E.E.; Vos, de W.M.

    2006-01-01

    The microbial world within us includes a vast array of gastrointestinal (GI) tract communities that play an important role in health and disease. Significant progress has been made in recent years in describing the intestinal microbial composition based on the application of 16S ribosomal RNA

  12. Microbial biofilms on facial prostheses

    NARCIS (Netherlands)

    Ariani, Nina; Vissink, Arjan; van Oort, Robert P.; Kusdhany, Lindawati; Djais, Ariadna; Rahardjo, Tri Budi W.; van der Mei, Henny C.; Krom, Bastiaan P.

    2012-01-01

    The composition of microbial biofilms on silicone rubber facial prostheses was investigated and compared with the microbial flora on healthy and prosthesis-covered skin. Scanning electron microscopy showed the presence of mixed bacterial and yeast biofilms on and deterioration of the surface of the

  13. Similar microbial communities found on two distant seafloor basalts

    Directory of Open Access Journals (Sweden)

    Esther eSinger

    2015-12-01

    Full Text Available The oceanic crust forms two thirds of the Earth’s surface and hosts a large phylogenetic and functional diversity of microorganisms. While advances have been made in the sedimentary realm, our understanding of the igneous rock portion as a microbial habitat has remained limited. We present the first comparative metagenomic microbial community analysis from ocean floor basalt environments at the Lō’ihi Seamount, Hawai’i, and the East Pacific Rise (EPR (9˚N. Phylogenetic analysis indicates the presence of a total of 43 bacterial and archaeal mono-phyletic groups, dominated by Alpha- and Gammaproteobacteria, as well as Thaumarchaeota. Functional gene analysis suggests that these Thaumarchaeota play an important role in ammonium oxidation on seafloor basalts. In addition to ammonium oxidation, the seafloor basalt habitat reveals a wide spectrum of other metabolic potentials, including CO2 fixation, denitrification, dissimilatory sulfate reduction, and sulfur oxidation. Basalt communities from Lō’ihi and the EPR show considerable metabolic and phylogenetic overlap down to the genus level despite geographic distance and slightly different seafloor basalt mineralogy.

  14. Microbial diversity in nonsulfur, sulfur and iron geothermal steam vents.

    Science.gov (United States)

    Benson, Courtney A; Bizzoco, Richard W; Lipson, David A; Kelley, Scott T

    2011-04-01

    Fumaroles, commonly called steam vents, are ubiquitous features of geothermal habitats. Recent studies have discovered microorganisms in condensed fumarole steam, but fumarole deposits have proven refractory to DNA isolation. In this study, we report the development of novel DNA isolation approaches for fumarole deposit microbial community analysis. Deposit samples were collected from steam vents and caves in Hawaii Volcanoes National Park, Yellowstone National Park and Lassen Volcanic National Park. Samples were analyzed by X-ray microanalysis and classified as nonsulfur, sulfur or iron-dominated steam deposits. We experienced considerable difficulty in obtaining high-yield, high-quality DNA for cloning: only half of all the samples ultimately yielded sequences. Analysis of archaeal 16S rRNA gene sequences showed that sulfur steam deposits were dominated by Sulfolobus and Acidianus, while nonsulfur deposits contained mainly unknown Crenarchaeota. Several of these novel Crenarchaeota lineages were related to chemoautotrophic ammonia oxidizers, indicating that fumaroles represent a putative habitat for ammonia-oxidizing Archaea. We also generated archaeal and bacterial enrichment cultures from the majority of the deposits and isolated members of the Sulfolobales. Our results provide the first evidence of Archaea in geothermal steam deposits and show that fumaroles harbor diverse and novel microbial lineages. © 2011 Federation of European Microbiological Societies. Published by Blackwell Publishing Ltd. All rights reserved.

  15. Microbial life in ice and subglacial environments

    Science.gov (United States)

    Price, P. B.; Bramall, N.; Tatebe, K.

    2003-04-01

    Conditions for microbial life to exist in solid ice require the presence of liquid water and sources of energy and bioelements. In ice in thermal equilibrium, liquid water will exist in a three-dimensional network of micron-sized veins and in nanometer-thick films on mineral grains in ice. Ionic impurities lower the freezing temperature in the veins to as low as -95^oC. Depending on mineral type, the film on a grain surface will remain liquid down to ˜ -40^oC. The impurities provide both energy (via microbially catalyzed redox reactions) and bioelements. The maximum sustainable microbial population depends on metabolic rate, which in turn depends on species, temperature, and type and concentration of impurities in veins and surfaces. Microbes have been imaged by epifluorescence in veins in sea and Arctic lake ice and on grains in Dry Valleys lake ice. Indirect evidence exists for metabolism of microbes in Vostok glacial ice, in Greenland basal ice, and in Sajama (Bolivia) glacial ice. We will discuss several approaches to detection of microbes: epifluorescence microscopy of glacial ice at low temperature; fluorescence spectra taken with BSL (a new borehole logging instrument); fluorescence of microbes on surfaces of silt and volcanic ash in glacial ice; and in-situ cultivation of bacterial colonies at intersections of mineral grains and liquid veins in ice held in contact with a nutrient medium at subfreezing temperature. Based on measurements in the oligotrophic Lake Tahoe, BSL is sensitive to a concentration of ˜10^3 microbes cm-3, which may be adequate to detect life in Greenland ice and in Lake Vostok. A miniaturized version could be used to search for life in Martian permafrost and in diapirs in Europan ice.

  16. Fish habitat selection in a large hydropeaking river: Strong individual and temporal variations revealed by telemetry.

    Science.gov (United States)

    Capra, Hervé; Plichard, Laura; Bergé, Julien; Pella, Hervé; Ovidio, Michaël; McNeil, Eric; Lamouroux, Nicolas

    2017-02-01

    Modeling individual fish habitat selection in highly variable environments such as hydropeaking rivers is required for guiding efficient management decisions. We analyzed fish microhabitat selection in the heterogeneous hydraulic and thermal conditions (modeled in two-dimensions) of a reach of the large hydropeaking Rhône River locally warmed by the cooling system of a nuclear power plant. We used modern fixed acoustic telemetry techniques to survey 18 fish individuals (five barbels, six catfishes, seven chubs) signaling their position every 3s over a three-month period. Fish habitat selection depended on combinations of current microhabitat hydraulics (e.g. velocity, depth), past microhabitat hydraulics (e.g. dewatering risk or maximum velocities during the past 15days) and to a lesser extent substrate and temperature. Mixed-effects habitat selection models indicated that individual effects were often stronger than specific effects. In the Rhône, fish individuals appear to memorize spatial and temporal environmental changes and to adopt a "least constraining" habitat selection. Avoiding fast-flowing midstream habitats, fish generally live along the banks in areas where the dewatering risk is high. When discharge decreases, however, they select higher velocities but avoid both dewatering areas and very fast-flowing midstream habitats. Although consistent with the available knowledge on static fish habitat selection, our quantitative results demonstrate temporal variations in habitat selection, depending on individual behavior and environmental history. Their generality could be further tested using comparative experiments in different environmental configurations. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Hydrodynamics of microbial filter feeding

    DEFF Research Database (Denmark)

    Nielsen, Lasse Tor; Asadzadeh, Seyed Saeed; Dölger, Julia

    2017-01-01

    Microbial filter feeders are an important group of grazers, significant to the microbial loop, aquatic food webs, and biogeochemical cycling. Our understanding of microbial filter feeding is poor, and, importantly, it is unknown what force microbial filter feeders must generate to process adequate...... amounts of water. Also, the trade-off in the filter spacing remains unexplored, despite its simple formulation: A filter too coarse will allow suitably sized prey to pass unintercepted, whereas a filter too fine will cause strong flow resistance. We quantify the feeding flow of the filter......-feeding choanoflagellate Diaphanoeca grandis using particle tracking, and demonstrate that the current understanding of microbial filter feeding is inconsistent with computational fluid dynamics (CFD) and analytical estimates. Both approaches underestimate observed filtration rates by more than an order of magnitude...

  18. Host-specific effects of soil microbial filtrates prevail over those of arbuscular mycorrhizae in a fragmented landscape.

    Science.gov (United States)

    Pizano, Camila; Mangan, Scott A; Graham, James H; Kitajima, Kaoru

    2017-09-01

    Plant-soil interactions have been shown to determine plant community composition in a wide range of environments. However, how plants distinctly interact with beneficial and detrimental organisms across mosaic landscapes containing fragmented habitats is still poorly understood. We experimentally tested feedback responses between plants and soil microbial communities from adjacent habitats across a disturbance gradient within a human-modified tropical montane landscape. In a greenhouse experiment, two components of soil microbial communities were amplified; arbuscular mycorrhizal fungi (AMF) and a filtrate excluding AMF spores from the soils of pastures (high disturbance), coffee plantations (intermediate disturbance), and forest fragments (low disturbance), using potted seedlings of 11 plant species common in these habitats (pasture grass, coffee, and nine native species). We then examined their effects on growth of these same 11 host species with reciprocal habitat inoculation. Most plant species received a similar benefit from AMF, but differed in their response to the filtrates from the three habitats. Soil filtrate from pastures had a net negative effect on plant growth, while filtrates from coffee plantations and forests had a net positive effect on plant growth. Pasture grass, coffee, and five pioneer tree species performed better with the filtrate from "away" (where these species rarely occur) compared to "home" (where these species typically occur) habitat soils, while four shade-tolerant tree species grew similarly with filtrates from different habitats. These results suggest that pastures accumulate species-specific soil enemies, while coffee plantations and forests accumulate beneficial soil microbes that benefit pioneer native plants and coffee, respectively. Thus, compared to AMF, soil filtrates exerted stronger habitat and host-specific effects on plants, being more important mediators of plant-soil feedbacks across contrasting habitats. © 2017 by

  19. Insights into the phylogeny and coding potential of microbial dark matter

    OpenAIRE

    Rinke, Christian; Schwientek, Patrick; Sczyrba, Alexander; Ivanova, Natalia N.; Anderson, Iain J.; Cheng, Jan-Fang; Darling, Aaron; Malfatti, Stephanie; Brandon K Swan; Gies, Esther A; Dodsworth, Jeremy A.; Hedlund, Brian P; Tsiamis, George; Sievert, Stefan M.; Liu, Wen-Tso

    2013-01-01

    Genome sequencing enhances our understanding of the biological world by providing blueprints for the evolutionary and functional diversity that shapes the biosphere. However, microbial genomes that are currently available are of limited phylogenetic breadth, owing to our historical inability to cultivate most microorganisms in the laboratory. We apply single-cell genomics to target and sequence 201 uncultivated archaeal and bacterial cells fromnine diverse habitats belonging to 29 major mostl...

  20. Island Species Richness Increases with Habitat Diversity

    NARCIS (Netherlands)

    Hortal, J.; Triantis, K.A.; Meiri, S.; Thebault, E.M.C.; Sfenthourakis, S.

    2009-01-01

    Species richness is commonly thought to increase with habitat diversity. However, a recent theoretical model aiming to unify niche and island biogeography theories predicted a hump-shaped relationship between richness and habitat diversity. Given the contradiction between model results and previous

  1. Habitat Use and Selection by Giant Pandas.

    Directory of Open Access Journals (Sweden)

    Vanessa Hull

    Full Text Available Animals make choices about where to spend their time in complex and dynamic landscapes, choices that reveal information about their biology that in turn can be used to guide their conservation. Using GPS collars, we conducted a novel individual-based analysis of habitat use and selection by the elusive and endangered giant pandas (Ailuropoda melanoleuca. We constructed spatial autoregressive resource utilization functions (RUF to model the relationship between the pandas' utilization distributions and various habitat characteristics over a continuous space across seasons. Results reveal several new insights, including use of a broader range of habitat characteristics than previously understood for the species, particularly steep slopes and non-forest areas. We also used compositional analysis to analyze habitat selection (use with respect to availability of habitat types at two selection levels. Pandas selected against low terrain position and against the highest clumped forest at the at-home range level, but no significant factors were identified at the within-home range level. Our results have implications for modeling and managing the habitat of this endangered species by illustrating how individual pandas relate to habitat and make choices that differ from assumptions made in broad scale models. Our study also highlights the value of using a spatial autoregressive RUF approach on animal species for which a complete picture of individual-level habitat use and selection across space is otherwise lacking.

  2. Forest wildlife habitat statistics for Maine - 1982

    Science.gov (United States)

    Robert T. Brooks; Thomas S. Frieswyk; Arthur Ritter

    1986-01-01

    A statistical report on the first forest wildlife habitat survey of Maine (1982). Eighty-five tables show estimates of forest area and several attributes of forest land wildlife habitat. Data are presented at two levels: state and geographic sampling unit.

  3. Habitat preference of Roan Antelope (Hippotragus equinus ...

    African Journals Online (AJOL)

    (Musila et al., 2001). A major problem facing wildlife conservation is increasing rate of habitat loss due to human activities through the destruction of their natural ..... water and feeding in Riparian habitat during dry season. It was also observed that Roan frequently visited salt licks close to Roan gate and Oli river complex.

  4. Habitat fragmentation causes rapid genetic differentiation and ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-08-04

    Aug 4, 2009 ... 1Laboratory of Plant Molecular Epigenetics, Institute of Genetics and Cytology, Northeast Normal University, Changchun. 130024 ... epigenetic variation studies can be included in habitat fragmentation analysis and its implications in inducing ... together with the environment habitat selection pressure.

  5. Estuaries and Tidal Marshes. Habitat Pac.

    Science.gov (United States)

    Fish and Wildlife Service (Dept. of Interior), Washington, DC.

    This educational packet consists of an overview, three lesson plans, student data sheets, and a poster. The overview examines estuaries and tidal or salt marshes by discussing the plants and animals in these habitats, marsh productivity, benefits and management of the habitats, historical aspects, and development and pollution. A glossary and list…

  6. Pollen and gene flow in fragmented habitats

    NARCIS (Netherlands)

    Kwak, Manja M.; Velterop, Odilia; van Andel, Jelte

    . Habitat fragmentation affects both plants and pollinators. Habitat fragmentation leads to changes in species richness, population number and size, density, and shape, thus to changes in the spatial arrangement of flowers. These changes influence the amount of food for flower-visiting insects and

  7. Thermal insulator

    Energy Technology Data Exchange (ETDEWEB)

    Yamamoto, R.; Asada, Y.; Matsuo, Y.; Mikoda, M.

    1985-07-16

    A thermal insulator comprises an expanded resin body having embedded therein an evacuated powder insulation portion which consists of fine powder and a container of film-like plastics or a film-like composite of plastics and metal for enclosing the powder. The resin body has been expanded by a Freon gas as a blowing agent. Since a Freon gas has a larger molecular diameter than the constituent gases of air, it is less likely to permeate through the container than air. Thus present invention provides a novel composite insulator which fully utilizes the benefits of vacuum insulation without necessitating a strong and costly material for a vacuum container.

  8. Monitoring Microbially Influenced Corrosion

    DEFF Research Database (Denmark)

    Hilbert, Lisbeth Rischel

    Abstract Microbially influenced corrosion (MIC) of carbon steel may occur in media with microbiological activity of especially sulphate-reducing bacteria (SRB). The applicability and reliability of a number of corrosion monitoring techniques for monitoring MIC has been evaluated in experiments...... and diffusional effects and unreliable corrosion rates, when biofilm and ferrous sulphide corrosion products cover the steel surface. Corrosion rates can be overestimated by a factor of 10 to 100 by electrochemical techniques. Weight loss coupons and ER are recommended as necessary basic monitoring techniques....... EIS might be used for detection of MIC as the appearance of very large capacitances can be attributed to the combined ferrous sulphide and biofilm formation. Capacitance correlates directly with sulphide concentration in sterile sulphide media. Keywords: Corrosion monitoring, carbon steel, MIC, SRB...

  9. Drinking water microbial myths.

    Science.gov (United States)

    Allen, Martin J; Edberg, Stephen C; Clancy, Jennifer L; Hrudey, Steve E

    2015-01-01

    Accounts of drinking water-borne disease outbreaks have always captured the interest of the public, elected and health officials, and the media. During the twentieth century, the drinking water community and public health organizations have endeavored to craft regulations and guidelines on treatment and management practices that reduce risks from drinking water, specifically human pathogens. During this period there also evolved misunderstandings as to potential health risk associated with microorganisms that may be present in drinking waters. These misunderstanding or "myths" have led to confusion among the many stakeholders. The purpose of this article is to provide a scientific- and clinically-based discussion of these "myths" and recommendations for better ensuring the microbial safety of drinking water and valid public health decisions.

  10. Microbial desulfurization of dibenzothiophene

    Energy Technology Data Exchange (ETDEWEB)

    van Afferden, M.; Schacht, S.; Beyer, M.; Klein, J.

    1988-01-01

    Concerning the sulfur removal from coal before combustion there is considerable interest in microbial methods as pyrite oxidation and elimination of organically bound sulfur from coal. Using organic sulfur compounds relevant for coal the mechanism of desulfurization was investigated. The authors isolated a defined mixed culture (FODO) able to utilize dibenzothiophene as sole sulfur source for growth, while benzoate was used as carbon source. The mixed culture FODO consists of an Alcaligenes denitrificans subspecies and a Brevibacterium species. Two metabolites of the degradation and dibenzothiophene-5-dioxide. The subsequent degradation of dibenzothiophene-5-dioxide used as sole sulfur source results in a release of sulfate ions into the medium. The results suggest a sulfur specific oxidative mechanism for removal of sulfur from dibenzothiophene.

  11. New microbial growth factor

    Science.gov (United States)

    Bok, S. H.; Casida, L. E., Jr.

    1977-01-01

    A screening procedure was used to isolate from soil a Penicillium sp., two bacterial isolates, and a Streptomyces sp. that produced a previously unknown microbial growth factor. This factor was an absolute growth requirement for three soil bacteria. The Penicillium sp. and one of the bacteria requiring the factor, an Arthrobacter sp., were selected for more extensive study concerning the production and characteristics of the growth factor. It did not seem to be related to the siderochromes. It was not present in soil extract, rumen fluid, or any other medium component tested. It appears to be a glycoprotein of high molecular weight and has high specific activity. When added to the diets for a meadow-vole mammalian test system, it caused an increased consumption of diet without a concurrent increase in rate of weight gain.

  12. Does habitat complexity influence fish recruitment?

    Directory of Open Access Journals (Sweden)

    A. CHEMINÉE

    2015-01-01

    Full Text Available Human activities facilitate coastal habitat transformation and homogenization. The spread of marine invasive species is one example. This in turn may influence fish recruitment and the subsequent replenishment of adult assemblages. We tested habitat complexity effect on fish (Teleostei recruitment by experimentally manipulating meadows of the habitat-forming invasive macroalga Caulerpa taxifolia (Chlorophyta. Among the fourteen fish species recorded during the experiment, only two labrids (Coris julis and Symphodus ocellatus settled in abundance among these meadows. Patterns in the abundance of these juveniles suggested that reduced tri-dimensional meadow complexity may reduce habitat quality and result in altered habitat choices and / or differential mortality of juveniles, therefore reducing fish recruitment and likely the abundance of adults.

  13. The microbial community in decaying fallen logs varies with critical period in an alpine forest.

    Science.gov (United States)

    Chang, Chenhui; Wu, Fuzhong; Yang, Wanqin; Xu, Zhenfeng; Cao, Rui; He, Wei; Tan, Bo; Justine, Meta Francis

    2017-01-01

    Little information has been available on the shifts in the microbial community in decaying fallen logs during critical periods in cold forests. Minjiang fir (Abies faxoniana) fallen logs in decay classes I-V were in situ incubated on the forest floor of an alpine forest in the eastern Tibet Plateau. The microbial community was investigated during the seasonal snow cover period (SP), snow thawing period (TP), early growing season (EG) and late growing season (LG) using Phosphorous Lipid Fatty Acid (PLFA) analysis. Total microbial biomass and microbial diversity in fallen logs were much more affected by critical period than decay class, whereas decay class had a stronger effect on microbial diversity than on microbial biomass. Abundant microbial biomass and microbial diversity in logs even without the cover of snow were observed in winter, which could not be linked to thermal insulation by snow cover. The freshly decayed logs functioned as an excellent buffer of environmental variation for microbial organisms during the sharp fluctuations in temperature in winter. We also found distinct decay patterns along with seasonality for heartwood, sapwood and bark, which requires further detailed research. Gram- bacteria mainly dominated the shifts in microbial community composition from SP to EG, while fungi and Gram+ bacteria mainly dominated it from SP to TP. Based on previous work and the present study, we conclude that fallen logs on the forest floor alter ecological processes by influencing microbial communities on woody debris and beneath the soil and litter. Our study also emphasizes the need to maintain a number of fallen logs, especially fresh ones, on the forest floor.

  14. Measuring microbial fitness in a field reciprocal transplant experiment.

    Science.gov (United States)

    Boynton, Primrose J; Stelkens, Rike; Kowallik, Vienna; Greig, Duncan

    2017-05-01

    Microbial fitness is easy to measure in the laboratory, but difficult to measure in the field. Laboratory fitness assays make use of controlled conditions and genetically modified organisms, neither of which are available in the field. Among other applications, fitness assays can help researchers detect adaptation to different habitats or locations. We designed a competitive fitness assay to detect adaptation of Saccharomyces paradoxus isolates to the habitat they were isolated from (oak or larch leaf litter). The assay accurately measures relative fitness by tracking genotype frequency changes in the field using digital droplet PCR (DDPCR). We expected locally adapted S. paradoxus strains to increase in frequency over time when growing on the leaf litter type from which they were isolated. The DDPCR assay successfully detected fitness differences among S. paradoxus strains, but did not find a tendency for strains to be adapted to the habitat they were isolated from. Instead, we found that the natural alleles of the hexose transport gene we used to distinguish S. paradoxus strains had significant effects on fitness. The origin of a strain also affected its fitness: strains isolated from oak litter were generally fitter than strains from larch litter. Our results suggest that dispersal limitation and genetic drift shape S. paradoxus populations in the forest more than local selection does, although further research is needed to confirm this. Tracking genotype frequency changes using DDPCR is a practical and accurate microbial fitness assay for natural environments. © 2016 The Authors. Molecular Ecology Resources Published by John Wiley & Sons Ltd.

  15. Bacterial Community Composition and Potential Driving Factors in Different Reef Habitats of the Spermonde Archipelago, Indonesia

    Directory of Open Access Journals (Sweden)

    Hauke F. Kegler

    2017-04-01

    Full Text Available Coastal eutrophication is a key driver of shifts in bacterial communities on coral reefs. With fringing and patch reefs at varying distances from the coast the Spermonde Archipelago in southern Sulawesi, Indonesia offers ideal conditions to study the effects of coastal eutrophication along a spatially defined gradient. The present study investigated bacterial community composition of three coral reef habitats: the water column, sediments, and mucus of the hard coral genus Fungia, along that cross-shelf environmental and water quality gradient. The main research questions were: (1 How do water quality and bacterial community composition change along a coastal shelf gradient? (2 Which water quality parameters influence bacterial community composition? (3 Is there a difference in bacterial community composition among the investigated habitats? For this purpose, a range of key water parameters were measured at eight stations in distances from 2 to 55 km from urban Makassar. This was supplemented by sampling of bacterial communities of important microbial habitats using 454 pyrosequencing. Findings revealed that the population center Makassar had a strong effect on the concentrations of Chlorophyll a, suspended particulate matter (SPM, and transparent exopolymer particles (TEP, which were all significantly elevated at the inshore compared the other seven sites. Shifts in the bacterial communities were specific to each sampled habitat. Two OTUs, belonging to the genera Escherichia/Shigella (Gammaproteobacteria and Ralstonia (Betaproteobacteria, respectively, both dominated the bacterial community composition of the both size fractions of the water column and coral mucus. The sampled reef sediments were more diverse, and no single OTUs was dominant. There was no gradual shift in bacterial classes or OTUs within the sampled habitats. In addition, we observed very distinct communities between the investigated habitats. Our data show strong changes in the

  16. Bacterial Community Composition and Potential Driving Factors in Different Reef Habitats of the Spermonde Archipelago, Indonesia

    Science.gov (United States)

    Kegler, Hauke F.; Lukman, Muhammad; Teichberg, Mirta; Plass-Johnson, Jeremiah; Hassenrück, Christiane; Wild, Christian; Gärdes, Astrid

    2017-01-01

    Coastal eutrophication is a key driver of shifts in bacterial communities on coral reefs. With fringing and patch reefs at varying distances from the coast the Spermonde Archipelago in southern Sulawesi, Indonesia offers ideal conditions to study the effects of coastal eutrophication along a spatially defined gradient. The present study investigated bacterial community composition of three coral reef habitats: the water column, sediments, and mucus of the hard coral genus Fungia, along that cross-shelf environmental and water quality gradient. The main research questions were: (1) How do water quality and bacterial community composition change along a coastal shelf gradient? (2) Which water quality parameters influence bacterial community composition? (3) Is there a difference in bacterial community composition among the investigated habitats? For this purpose, a range of key water parameters were measured at eight stations in distances from 2 to 55 km from urban Makassar. This was supplemented by sampling of bacterial communities of important microbial habitats using 454 pyrosequencing. Findings revealed that the population center Makassar had a strong effect on the concentrations of Chlorophyll a, suspended particulate matter (SPM), and transparent exopolymer particles (TEP), which were all significantly elevated at the inshore compared the other seven sites. Shifts in the bacterial communities were specific to each sampled habitat. Two OTUs, belonging to the genera Escherichia/Shigella (Gammaproteobacteria) and Ralstonia (Betaproteobacteria), respectively, both dominated the bacterial community composition of the both size fractions of the water column and coral mucus. The sampled reef sediments were more diverse, and no single OTUs was dominant. There was no gradual shift in bacterial classes or OTUs within the sampled habitats. In addition, we observed very distinct communities between the investigated habitats. Our data show strong changes in the bacterial

  17. Microbial biosensors for environmental monitoring

    Directory of Open Access Journals (Sweden)

    David VOGRINC

    2015-12-01

    Full Text Available Microbial biosensors are analytical devices capable of sensing substances in the environment due to the specific biological reaction of the microorganism or its parts. Construction of a microbial biosensor requires knowledge of microbial response to the specific analyte. Linking this response with the quantitative data, using a transducer, is the crucial step in the construction of a biosensor. Regarding the transducer type, biosensors are divided into electrochemical, optical biosensors and microbial fuel cells. The use of the proper configuration depends on the selection of the biosensing element. With the use of transgenic E. coli strains, bioluminescence or fluorescence based biosensors were developed. Microbial fuel cells enable the use of the heterogeneous microbial populations, isolated from wastewater. Different microorganisms are used for different pollutants – pesticides, heavy metals, phenolic compounds, organic waste, etc. Biosensing enables measurement of their concentration and their toxic or genotoxic effects on the microbes. Increasing environmental awareness has contributed to the increase of interest for biomonitoring. Although technologies, such as bioinformatics and genetic engineering, allow us to design complex and efficient microbial biosensors for environmental pollutants, the transfer of the laboratory work to the field still remains a problem to solve.

  18. Stochastic and deterministic assembly processes in subsurface microbial communities.

    Science.gov (United States)

    Stegen, James C; Lin, Xueju; Konopka, Allan E; Fredrickson, James K

    2012-09-01

    A major goal of microbial community ecology is to understand the forces that structure community composition. Deterministic selection by specific environmental factors is sometimes important, but in other cases stochastic or ecologically neutral processes dominate. Lacking is a unified conceptual framework aiming to understand why deterministic processes dominate in some contexts but not others. Here we work toward such a framework. By testing predictions derived from general ecological theory we aim to uncover factors that govern the relative influences of deterministic and stochastic processes. We couple spatiotemporal data on subsurface microbial communities and environmental parameters with metrics and null models of within and between community phylogenetic composition. Testing for phylogenetic signal in organismal niches showed that more closely related taxa have more similar habitat associations. Community phylogenetic analyses further showed that ecologically similar taxa coexist to a greater degree than expected by chance. Environmental filtering thus deterministically governs subsurface microbial community composition. More importantly, the influence of deterministic environmental filtering relative to stochastic factors was maximized at both ends of an environmental variation gradient. A stronger role of stochastic factors was, however, supported through analyses of phylogenetic temporal turnover. Although phylogenetic turnover was on average faster than expected, most pairwise comparisons were not themselves significantly non-random. The relative influence of deterministic environmental filtering over community dynamics was elevated, however, in the most temporally and spatially variable environments. Our results point to general rules governing the relative influences of stochastic and deterministic processes across micro- and macro-organisms.

  19. Microbial Communities in a High Arctic Polar Desert Landscape.

    Science.gov (United States)

    McCann, Clare M; Wade, Matthew J; Gray, Neil D; Roberts, Jennifer A; Hubert, Casey R J; Graham, David W

    2016-01-01

    The High Arctic is dominated by polar desert habitats whose microbial communities are poorly understood. In this study, we used next generation sequencing to describe the α- and β-diversity of microbial communities in polar desert soils from the Kongsfjorden region of Svalbard. Ten phyla dominated the soils and accounted for 95% of all sequences, with the Proteobacteria, Actinobacteria, and Chloroflexi being the major lineages. In contrast to previous investigations of Arctic soils, relative Acidobacterial abundances were found to be very low as were the Archaea throughout the Kongsfjorden polar desert landscape. Lower Acidobacterial abundances were attributed to characteristic circumneutral soil pHs in this region, which has resulted from the weathering of underlying carbonate bedrock. In addition, we compared previously measured geochemical conditions as possible controls on soil microbial communities. Phosphorus, pH, nitrogen, and calcium levels all significantly correlated with β-diversity, indicating landscape-scale lithological control of available nutrients, which in turn, significantly influenced soil community composition. In addition, soil phosphorus and pH significantly correlated with α-diversity, particularly with the Shannon diversity and Chao 1 richness indices.

  20. Microbial diversity and stratification of South Pacific abyssal marine sediments.

    Science.gov (United States)

    Durbin, Alan M; Teske, Andreas

    2011-12-01

    Abyssal marine sediments cover a large proportion of the ocean floor, but linkages between their microbial community structure and redox stratification have remained poorly constrained. This study compares the downcore gradients in microbial community composition to porewater oxygen and nitrate concentration profiles in an abyssal marine sediment column in the South Pacific Ocean. Archaeal 16S rRNA clone libraries showed a stratified archaeal community that changed from Marine Group I Archaea in the aerobic and nitrate-reducing upper sediment column towards deeply branching, uncultured crenarchaeotal and euryarchaeotal lineages in nitrate-depleted, anaerobic sediment horizons. Bacterial 16S rRNA clone libraries revealed a similar shift on the phylum and subphylum level within the bacteria, from a complex community of Alpha-, Gamma- and Deltaproteobacteria, Actinobacteria and Gemmatimonadetes in oxic surface sediments towards uncultured Chloroflexi and Planctomycetes in the anaerobic sediment column. The distinct stratification of largely uncultured bacterial and archaeal groups within the oxic and nitrate-reducing marine sediment column provides initial constraints for their microbial habitat preferences. © 2011 Society for Applied Microbiology and Blackwell Publishing Ltd.

  1. Microbial diversity and carbon cycling in San Francisco Bay wetlands

    Energy Technology Data Exchange (ETDEWEB)

    Theroux, Susanna [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Hartman, Wyatt [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; He, Shaomei [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.; Univ. of Wisconsin, Madison, WI (United States); Tringe, Susannah [Lawrence Berkeley National Lab. (LBNL), Walnut Creek, CA (United States). Dept. of Energy Joint Genome Inst.

    2014-03-21

    Wetland restoration efforts in San Francisco Bay aim to rebuild habitat for endangered species and provide an effective carbon storage solution, reversing land subsidence caused by a century of industrial and agricultural development. However, the benefits of carbon sequestration may be negated by increased methane production in newly constructed wetlands, making these wetlands net greenhouse gas (GHG) sources to the atmosphere. We investigated the effects of wetland restoration on below-ground microbial communities responsible for GHG cycling in a suite of historic and restored wetlands in SF Bay. Using DNA and RNA sequencing, coupled with real-time GHG monitoring, we profiled the diversity and metabolic potential of wetland soil microbial communities. The wetland soils harbor diverse communities of bacteria and archaea whose membership varies with sampling location, proximity to plant roots and sampling depth. Our results also highlight the dramatic differences in GHG production between historic and restored wetlands and allow us to link microbial community composition and GHG cycling with key environmental variables including salinity, soil carbon and plant species.

  2. Kulm Wetland Management District annual habitat work plan 2005

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This annual habitat management plan outlines working habitat objectives for wetland habitats based on refuge purposes, professional judgment and experience for Kulm...

  3. NEKTON-HABITAT ASSOCIATIONS IN A PACIFIC NORTHWEST (USA) ESTUARY

    Science.gov (United States)

    Nekton−habitat associations were determined in Yaquina Bay, Oregon, United States, using a stratified-by-habitat, random, estuary-wide sampling design. Three habitats (intertidal eelgrass [Zostera marina], mud shrimp [Upogebia pugettensis], and ghost shrimp [Neotrypaea californie...

  4. Microbial indicators of aquatic ecosystem change: current applications to eutrophication studies.

    Science.gov (United States)

    Paerl, Hans W; Dyble, Julianne; Moisander, Pia H; Noble, Rachel T; Piehler, Michael F; Pinckney, James L; Steppe, Timothy F; Twomey, Luke; Valdes, Lexia M

    2003-12-01

    Human encroachment on aquatic ecosystems is increasing at an unprecedented rate. The impacts of human pollution and habitat alteration are most evident and of greatest concern at the microbial level, where a bulk of production and nutrient cycling takes place. Aquatic ecosystems are additionally affected by natural perturbations, including droughts, storms, and floods, the frequency and extent of which may be increasing. Distinguishing and integrating the impacts of natural and human stressors is essential for understanding environmentally driven change of microbial diversity and function. Microbial bioindicators play a major role in detecting and characterizing these changes. Complementary use of analytical and molecular indicator tools shows great promise in helping us clarify the processes underlying microbial population, community, and ecosystem change in response to environmental perturbations. This is illustrated in phytoplankton (microalgal and cyanobacterial) and bacterial community changes in a range of US estuarine and coastal ecosystems experiencing increasing development in their water- and airsheds as well as climatic changes (e.g., increasing hurricane frequency). Microbial indicators can be adapted to a range of monitoring programs, including ferries, moored instrumentation, and remote sensing, in order to evaluate environmental controls on microbial community structure and function over ecosystem to global scales.

  5. The microbial ecology of permafrost

    DEFF Research Database (Denmark)

    Jansson, Janet; Tas, Neslihan

    2014-01-01

    Permafrost constitutes a major portion of the terrestrial cryosphere of the Earth and is a unique ecological niche for cold-adapted microorganisms. There is a relatively high microbial diversity in permafrost, although there is some variation in community composition across different permafrost......-gas emissions. This Review describes new data on the microbial ecology of permafrost and provides a platform for understanding microbial life strategies in frozen soil as well as the impact of climate change on permafrost microorganisms and their functional roles....

  6. Defining Disturbance for Microbial Ecology.

    Science.gov (United States)

    Plante, Craig J

    2017-08-01

    Disturbance can profoundly modify the structure of natural communities. However, microbial ecologists' concept of "disturbance" has often deviated from conventional practice. Definitions (or implicit usage) have frequently included climate change and other forms of chronic environmental stress, which contradict the macrobiologist's notion of disturbance as a discrete event that removes biomass. Physical constraints and disparate biological characteristics were compared to ask whether disturbances fundamentally differ in microbial and macroorganismal communities. A definition of "disturbance" for microbial ecologists is proposed that distinguishes from "stress" and other competing terms, and that is in accord with definitions accepted by plant and animal ecologists.

  7. Pyrosequencing characterization of the microbiota from Atlantic intertidal marine sponges reveals high microbial diversity and the lack of co-occurrence patterns.

    Science.gov (United States)

    Alex, Anoop; Antunes, Agostinho

    2015-01-01

    Sponges are ancient metazoans that host diverse and complex microbial communities. Sponge-associated microbial diversity has been studied from wide oceans across the globe, particularly in subtidal regions, but the microbial communities from intertidal sponges have remained mostly unexplored. Here we used pyrosequencing to characterize the microbial communities in 12 different co-occurring intertidal marine sponge species sampled from the Atlantic coast, revealing a total of 686 operational taxonomic units (OTUs) at 97% sequence similarity. Taxonomic assignment of 16S ribosomal RNA tag sequences estimated altogether 26 microbial groups, represented by bacterial (75.5%) and archaeal (22%) domains. Proteobacteria (43.4%) and Crenarchaeota (20.6%) were the most dominant microbial groups detected in all the 12 marine sponge species and ambient seawater. The Crenarchaeota microbes detected in three Atlantic Ocean sponges had a close similarity with Crenarchaeota from geographically separated subtidal Red Sea sponges. Our study showed that most of the microbial communities observed in sponges (73%) were also found in the surrounding ambient seawater suggesting possible environmental acquisition and/or horizontal transfer of microbes. Beyond the microbial diversity and community structure assessments (NMDS, ADONIS, ANOSIM), we explored the interactions between the microbial communities coexisting in sponges using the checkerboard score (C-score). Analyses of the microbial association pattern (co-occurrence) among intertidal sympatric sponges revealed the random association of microbes, favoring the hypothesis that the sponge-inhabiting microbes are recruited from the habitat mostly by chance or influenced by environmental factors to benefit the hosts.

  8. CFD Analysis of Thermal Control System Using NX Thermal and Flow

    Science.gov (United States)

    Fortier, C. R.; Harris, M. F. (Editor); McConnell, S. (Editor)

    2014-01-01

    The Thermal Control Subsystem (TCS) is a key part of the Advanced Plant Habitat (APH) for the International Space Station (ISS). The purpose of this subsystem is to provide thermal control, mainly cooling, to the other APH subsystems. One of these subsystems, the Environmental Control Subsystem (ECS), controls the temperature and humidity of the growth chamber (GC) air to optimize the growth of plants in the habitat. The TCS provides thermal control to the ECS with three cold plates, which use Thermoelectric Coolers (TECs) to heat or cool water as needed to control the air temperature in the ECS system. In order to optimize the TCS design, pressure drop and heat transfer analyses were needed. The analysis for this system was performed in Siemens NX Thermal/Flow software (Version 8.5). NX Thermal/Flow has the ability to perform 1D or 3D flow solutions. The 1D flow solver can be used to represent simple geometries, such as pipes and tubes. The 1D flow method also has the ability to simulate either fluid only or fluid and wall regions. The 3D flow solver is similar to other Computational Fluid Dynamic (CFD) software. TCS performance was analyzed using both the 1D and 3D solvers. Each method produced different results, which will be evaluated and discussed.

  9. Microbial Biogeography on the Legacies of Historical Events in the Arctic Subsurface Sediments

    Science.gov (United States)

    Han, Dukki; Nam, Seung-Il; Hur, Hor-Gil

    2017-04-01

    The Arctic marine environment consists of various microbial habitats. The niche preference of microbial assemblages in the Arctic Ocean has been surveyed with the modern environmental change by oceanographic traits such as sea-ice dynamics, current circulation, and sedimentation. The North Pacific inflow from the shallow and narrow Bering Strait is highly susceptible to sea-level fluctuations, and thus the water mass exchange mediated by the history of sea-ice between the North Pacific and the Chukchi Sea in the Arctic Ocean. Over geological timescale, the climate change may provide putative evidences for ecological niche for the Arctic microbial assemblages as well as geological records in response to the paleoclimate change. In the present study, the multidisciplinary approach, based on microbiology, geology, and geochemistry, was applied to survey the microbial assemblages in the Arctic subsurface sediments and help further integrate the microbial biogeography and biogeochemical patterns in the Arctic subsurface biosphere. Our results describe microbial assemblages with high-resolution paleoceanographic records in the Chukchi Sea sediment core (ARA02B/01A-GC; 5.4 mbsf) to show the processes that drive microbial biogeographic patterns in the Arctic subsurface sediments. We found microbial habitat preferences closely linked to Holocene paleoclimate records as well as geological, geochemical, and microbiological evidence for the inference of the sulphate-methane transition zone (SMTZ) in the Chukchi Sea. Especially, the vertically distributed predominant populations of Gammaproteobacteria and Marine Group II Euryarchaeota in the ARA02B/01A-GC consistent with the patterns of the known global SMTZs and Holocene sedimentary records, suggesting that in-depth microbiological profiles integrated with geological records may be indirectly useful for reconstructing Arctic paleoclimate changes. In the earliest phase of Mid Holocene in the ARA02B/01A-GC with concentrated

  10. Phylogenetic and Functional Analysis of Metagenome Sequence from High-Temperature Archaeal Habitats Demonstrate Linkages between Metabolic Potential and Geochemistry

    DEFF Research Database (Denmark)

    Inskeep, William P; Jay, Zackary J; Herrgard, Markus

    2013-01-01

    .4 and to discuss specific examples where the metabolic potential correlated with measured environmental parameters and geochemical processes occurring in situ. Random shotgun metagenome sequence (∼40-45 Mb Sanger sequencing per site) was obtained from environmental DNA extracted from high-temperature sediments and......-temperature sites that contain microbial communities dominated by archaea relative to bacteria. The specific objectives of the study were to use metagenome sequencing to determine the structure and functional capacity of thermophilic archaeal-dominated microbial communities across a pH range from 2.5 to 6....../or microbial mats and subjected to numerous phylogenetic and functional analyses. Analysis of individual sequences (e.g., MEGAN and G + C content) and assemblies from each habitat type revealed the presence of dominant archaeal populations in all environments, 10 of whose genomes were largely reconstructed...

  11. Long Duration Life Test of Propylene Glycol Water Based Thermal Fluid Within Thermal Control Loop

    Science.gov (United States)

    Le, Hung; Hill, Charles; Stephan, Ryan A.

    2010-01-01

    Evaluations of thermal properties and resistance to microbial growth concluded that 50% Propylene Glycol (PG)-based fluid and 50% de-ionized water mixture was desirable for use as a fluid within a vehicle s thermal control loop. However, previous testing with a commercial mixture of PG and water containing phosphate corrosion inhibitors resulted in corrosion of aluminum within the test system and instability of the test fluid. This paper describes a follow-on long duration testing and analysis of 50% Propylene Glycol (PG)-based fluid and 50% de-ionized water mixture with inorganic corrosion inhibitors used in place of phosphates. The test evaluates the long-term fluid stability and resistance to microbial and chemical changes

  12. Thermal ecology of the fiddler crab Uca panacea: Thermal constraints and organismal responses.

    Science.gov (United States)

    Darnell, M Zachary; Nicholson, Haley S; Munguia, Pablo

    2015-08-01

    Temperature is one of the primary environmental variables limiting organismal performance, fitness, and species distributions. Yet, understanding temperature effects requires thorough exploration of thermal constraints and organismal responses that can translate to fitness and non-lethal long-term consequences under both constant and changing thermal regimes. We examined the thermal ecology of the fiddler crab Uca panacea, including critical thermal limits, thermal sensitivity of locomotion, operative environmental temperatures, preferred body temperatures, and acclimation ability. Operative environmental temperatures frequently reached the critical thermal maximum (41.8±0.8°C, mean ± s.e.m.), especially in unvegetated microhabitats, indicating the need for behavioral thermoregulation to maintain diurnal activity patterns. Preferred body temperatures (21.1-28.6°C) were substantially below the thermal optimum (30-40°C), although further research is needed to determine the driver of this mismatch. Critical thermal limits shifted 2-4°C in response to exposure to low (20°C) or high (35°C) temperatures, with full acclimation occurring in approximately 9d. This capacity for rapid acclimation, combined with the capacity for behavioral thermoregulation, is a strong candidate mechanism that explains the broad habitat use and could help explain the successful pantropical distribution of fiddler crabs. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Microbial ecology-based engineering of Microbial Electrochemical Technologies.

    Science.gov (United States)

    Koch, Christin; Korth, Benjamin; Harnisch, Falk

    2017-08-14

    Microbial ecology is devoted to the understanding of dynamics, activity and interaction of microorganisms in natural and technical ecosystems. Bioelectrochemical systems represent important technical ecosystems, where microbial ecology is of highest importance for their function. However, whereas aspects of, for example, materials and reactor engineering are commonly perceived as highly relevant, the study and engineering of microbial ecology are significantly underrepresented in bioelectrochemical systems. This shortfall may be assigned to a deficit on knowledge and power of these methods as well as the prerequisites for their thorough application. This article discusses not only the importance of microbial ecology for microbial electrochemical technologies but also shows which information can be derived for a knowledge-driven engineering. Instead of providing a comprehensive list of techniques from which it is hard to judge the applicability and value of information for a respective one, this review illustrates the suitability of selected techniques on a case study. Thereby, best practice for different research questions is provided and a set of key questions for experimental design, data acquisition and analysis is suggested. © 2017 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  14. Microbial community development on the surface of Hans and Werenskiold Glaciers (Svalbard, Arctic): a comparison.

    Science.gov (United States)

    Grzesiak, Jakub; Górniak, Dorota; Świątecki, Aleksander; Aleksandrzak-Piekarczyk, Tamara; Szatraj, Katarzyna; Zdanowski, Marek K

    2015-09-01

    Surface ice and cryoconite holes of two types of polythermal Svalbard Glaciers (Hans Glacier--grounded tidewater glacier and Werenskiold Glacier-land-based valley glacier) were investigated in terms of chemical composition, microbial abundance and diversity. Gathered data served to describe supraglacial habitats and to compare microbe-environment interactions on those different type glaciers. Hans Glacier samples displayed elevated nutrient levels (DOC, nitrogen and seston) compared to Werenskiold Glacier. Adjacent tundra formations, bird nesting sites and marine aerosol were candidates for allochtonic enrichment sources. Microbial numbers were comparable on both glaciers, with surface ice containing cells in the range of 10(4) mL(-1) and cryoconite sediment 10(8) g(-1) dry weight. Denaturating gradient gel electrophoresis band-based clustering revealed differences between glaciers in terms of dominant bacterial taxa structure. Microbial community on Werenskiold Glacier benefited from the snow-released substances. On Hans Glacier, this effect was not as pronounced, affecting mainly the photoautotrophs. Over-fertilization of Hans Glacier surface was proposed as the major factor, desensitizing the microbial community to the snow melt event. Nitrogen emerged as a limiting factor in surface ice habitats, especially to Eukaryotic algae.

  15. Microbial dynamics in glacier forefield soils show succession is not just skin deep.

    Science.gov (United States)

    Edwards, Arwyn; Cook, Sophie

    2015-03-01

    All over the world, glaciers are receding. One key consequence of glacier area loss is the creation of new terrestrial habitats. This presents an experimental opportunity to study both community formation and the implications of glacier loss for terrestrial ecosystems. In this issue of Molecular Ecology, Rime et al. (2015) describe how microbial communities are structured according to soil depth and development in the forefield of Damma glacier in Switzerland. The study provides insights into the contrasting structures of microbial communities at different stages of soil development. An important strength of the study is the integration of soil depth into the paradigm of primary succession, a feature which has rarely been considered by other studies. These findings underscore the importance of studying the interactions between microbial communities and glaciers at a time when Earth's glacial systems are experiencing profound change. © 2015 John Wiley & Sons Ltd.

  16. Effects of Host Phylogeny and Habitats on Gut Microbiomes of Oriental River Prawn (Macrobrachium nipponense.

    Directory of Open Access Journals (Sweden)

    Tzong-Der Tzeng

    Full Text Available The gut microbial community is one of the richest and most complex ecosystems on earth, and the intestinal microbes play an important role in host development and health. Next generation sequencing approaches, which rapidly produce millions of short reads that enable the investigation on a culture independent basis, are now popular for exploring microbial community. Currently, the gut microbiome in fresh water shrimp is unexplored. To explore gut microbiomes of the oriental river prawn (Macrobrachium nipponense and investigate the effects of host genetics and habitats on the microbial composition, 454 pyrosequencing based on the 16S rRNA gene were performed. We collected six groups of samples, including M. nipponense shrimp from two populations, rivers and lakes, and one sister species (M. asperulum as an out group. We found that Proteobacteria is the major phylum in oriental river prawn, followed by Firmicutes and Actinobacteria. Compositional analysis showed microbial divergence between the two shrimp species is higher than that between the two populations of one shrimp species collected from river and lake. Hierarchical clustering also showed that host genetics had a greater impact on the divergence of gut microbiome than host habitats. This finding was also congruent with the functional prediction from the metagenomic data implying that the two shrimp species still shared the same type of biological functions, reflecting a similar metabolic profile in their gut environments. In conclusion, this study provides the first investigation of the gut microbiome of fresh water shrimp, and supports the hypothesis of host species-specific signatures of bacterial community composition.

  17. Salmon River Habitat Enhancement, 1984 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Konopacky, Richard C.

    1986-04-01

    This report has four volumes: a Tribal project annual report (Part 1) and three reports (Parts 2, 3, and 4) prepared for the Tribes by their engineering subcontractor. The Tribal project annual report contains reports for four subprojects within Project 83-359. Subproject I involved habitat and fish inventories in Bear Valley Creek, Valley County, Idaho that will be used to evaluate responses to ongoing habitat enhancement. Subproject II is the coordination/planning activities of the Project Leader in relation to other BPA-funded habitat enhancement projects that have or will occur within the traditional Treaty (Fort Bridger Treaty of 1868) fishing areas of the Shoshone-Bannock Tribes, Fort Hall Reservation, Idaho. Subproject III involved habitat and fish inventories (pretreatment) and habitat problem identification on the Yankee Fork of the Salmon River (including Jordan Creek). Subproject IV during 1985 involved habitat problem identification in the East Fork of the Salmon River and habitat and fish inventories (pretreatment) in Herd Creek, a tributary to the East Fork.

  18. Does learning or instinct shape habitat selection?

    Directory of Open Access Journals (Sweden)

    Scott E Nielsen

    Full Text Available Habitat selection is an important behavioural process widely studied for its population-level effects. Models of habitat selection are, however, often fit without a mechanistic consideration. Here, we investigated whether patterns in habitat selection result from instinct or learning for a population of grizzly bears (Ursus arctos in Alberta, Canada. We found that habitat selection and relatedness were positively correlated in female bears during the fall season, with a trend in the spring, but not during any season for males. This suggests that habitat selection is a learned behaviour because males do not participate in parental care: a genetically predetermined behaviour (instinct would have resulted in habitat selection and relatedness correlations for both sexes. Geographic distance and home range overlap among animals did not alter correlations indicating that dispersal and spatial autocorrelation had little effect on the observed trends. These results suggest that habitat selection in grizzly bears are partly learned from their mothers, which could have implications for the translocation of wildlife to novel environments.

  19. Microbial Cell Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Doktycz, Mitchel John [ORNL; Sullivan, Claretta [Eastern Virginia Medical School; Mortensen, Ninell P [ORNL; Allison, David P [ORNL

    2011-01-01

    limitation on the maximum scan size (roughly 100 x 100 {mu}m) and the restricted movement of the cantilever in the Z (or height) direction. In most commercial AFMs, the Z range is restricted to roughly 10 {mu}m such that the height of cells to be imaged must be seriously considered. Nevertheless, AFM can provide structural-functional information at nanometer resolution and do so in physiologically relevant environments. Further, instrumentation for scanning probe microscopy continues to advance. Systems for high-speed imaging are becoming available, and techniques for looking inside the cells are being demonstrated. The ability to combine AFM with other imaging modalities is likely to have an even greater impact on microbiological studies. AFM studies of intact microbial cells started to appear in the literature in the 1990s. For example, AFM studies of Saccharomyces cerevisiae examined buddings cars after cell division and detailed changes related to cell growth processes. Also, the first AFM studies of bacterial biofilms appeared. In the late 1990s, AFM studies of intact fungal spores described clear changes in spore surfaces upon germination, and studies of individual bacterial cells were also described. These early bacterial imaging studies examined changes in bacterial morphology due to antimicrobial peptides exposure and bacterial adhesion properties. The majority of these early studies were carried out on dried samples and took advantage of the resolving power of AFM. The lack of cell mounting procedures presented an impediment for cell imaging studies. Subsequently, several approaches to mounting microbial cells have been developed, and these techniques are described later. Also highlighted are general considerations for microbial imaging and a description of some of the various applications of AFM to microbiology.

  20. Microbial hydrogen production

    Energy Technology Data Exchange (ETDEWEB)

    Weaver, P.F.; Maness, P.C.; Martin, S. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1995-09-01

    Photosynthetic bacteria inhabit an anaerobic or microaerophilic world where H{sub 2} is produced and consumed as a shared intermediary metabolite. Within a given bacterial isolate there are as many as 4 to 6 distinct enzymes that function to evolve or consume H{sub 2}. Three of the H{sub 2}-evolving physiologies involving three different enzymes from photosynthetic bacteria have been examined in detail for commercial viability. Nitrogenase-mediated H{sub 2} production completely dissimilates many soluble organic compounds to H{sub 2} and CO{sub 2} at rates up to 131 {mu}mol H{sub 2}{sm_bullet}min{sup -1}{sm_bullet}g cdw{sup -1} and can remain active for up to 20 days. This metabolism is very energy intensive, however, which limits solar conversion efficiencies. Fermentative hydrogenase can produce H{sub 2} at rates of 440 {mu}mol{sm_bullet}min{sup -1}{sm_bullet}g cdw{sup -1} at low levels of irradiation over indefinite periods. The equilibrium for this activity is low (<0.15 atmospheres), thereby requiring gas sparging, vacuuming, or microbial scavenging to retain prolonged activity. Microbial H{sub 2} production from the CO component of synthesis or producer gases maximally reaches activities of 1.5 mmol{sm_bullet}min{sup -1}{sm_bullet}g cdw{sup -1}. Mass transport of gaseous CO into an aqueous bacterial suspension is the rate-limiting step. Increased gas pressure strongly accelerates these rates. Immobilized bacteria on solid supports at ambient pressures also show enhanced shift activity when the bulk water is drained away. Scaled-up bioreactors with 100-200 cc bed volume have been constructed and tested. The near-term goal of this portion of the project is to engineer and economically evaluate a prototype system for the biological production of H{sub 2} from biomass. The CO shift enables a positive selection technique for O{sub 2}-resistant, H{sub 2}-evolving bacterial enzymes from nature.

  1. MICROBIAL MATS - A JOINT VENTURE

    NARCIS (Netherlands)

    VANGEMERDEN, H

    Microbial mats characteristically are dominated by a few functional groups of microbes: cyanobacteria, colorless sulfur bacteria, purple sulfur bacteria, and sulfate-reducing bacteria. Their combined metabolic activities result in steep environmental microgradients, particularly of oxygen and

  2. Microbial Abundance and Diversity Patterns Associated with Sediments and Carbonates from the Methane Seep Environments of Hydrate Ridge, OR

    Directory of Open Access Journals (Sweden)

    Jeffrey James Marlow

    2014-10-01

    Full Text Available Methane seeps are among the most productive habitats along continental margins, as anaerobic methane-oxidizing euryarchaeaota and sulfur-metabolizing deltaproteobacteria form the biological base of a dynamic deep-sea ecosystem. The degree of methane seepage therefore represents one important variable in ecosystem dynamics, and the recent discovery of carbonate-hosted endolithic methanotrophy exposes another potentially discriminating factor: physical substrate type. Methanotrophic microbial communities have been detected within diverse seep-associated habitats, including unlithified sediments, protolithic carbonate nodules, and lithified carbonate slabs and chemoherms of distinct mineralogies. However, a systematic assessment of the diversity and community structure associated with these different habitats has been lacking. In this study, microbial aggregate analysis, microbial abundance quantification, mineralogical identification, and archaeal and bacterial 16S rRNA gene clone libraries were used to deconvolve the relationships between seepage activity, substrate type, and microbial community structure. We report prevalent methane-oxidizing archaeal lineages in both active and low-activity seep settings, and a strong community dependence on both seepage activity and substrate type. Statistical treatments of relative taxa abundances indicate that archaeal community structure is more dependent on the degree of methane seepage than physical substrate type; bacterial assemblages appear to be more strongly influenced by the type of colonization substrate than seepage activity. These findings provide a window into the determinants of community structure and function, improving our understanding of potential elemental cycling at seep sites.

  3. Microbial factories for recombinant pharmaceuticals

    OpenAIRE

    Domingo-Espín Joan; Ferrer-Miralles Neus; Corchero José; Vázquez Esther; Villaverde Antonio

    2009-01-01

    Abstract Most of the hosts used to produce the 151 recombinant pharmaceuticals so far approved for human use by the Food and Drug Administration (FDA) and/or by the European Medicines Agency (EMEA) are microbial cells, either bacteria or yeast. This fact indicates that despite the diverse bottlenecks and obstacles that microbial systems pose to the efficient production of functional mammalian proteins, namely lack or unconventional post-translational modifications, proteolytic instability, po...

  4. Microbial genomes: Blueprints for life

    Energy Technology Data Exchange (ETDEWEB)

    Relman, David A.; Strauss, Evelyn

    2000-12-31

    Complete microbial genome sequences hold the promise of profound new insights into microbial pathogenesis, evolution, diagnostics, and therapeutics. From these insights will come a new foundation for understanding the evolution of single-celled life, as well as the evolution of more complex life forms. This report is an in-depth analysis of scientific issues that provides recommendations and will be widely disseminated to the scientific community, federal agencies, industry and the public.

  5. The effects of habitat on coral bleaching responses in Kenya.

    Science.gov (United States)

    Grimsditch, Gabriel; Mwaura, Jelvas M; Kilonzo, Joseph; Amiyo, Nassir

    2010-06-01

    This study examines the bleaching responses of scleractinian corals at four sites in Kenya (Kanamai, Vipingo, Mombasa and Nyali) representing two distinct lagoon habitats (relatively shallow and relatively deep). Bleaching incidence was monitored for the whole coral community, while zooxanthellae densities and chlorophyll levels were monitored for target species (Pocillopora damicornis, Porites lutea, and Porites cylindrica) during a non-bleaching year (2006) and a year of mild-bleaching (2007). Differences in bleaching responses between habitats were observed, with shallower sites Kanamai and Vipingo exhibiting lower bleaching incidence than deeper sites Nyali and Mombasa. These shallower lagoons display more fluctuating thermal and light environments than the deeper sites, suggesting that corals in the shallower lagoons have acclimatized and/or adapted to the fluctuating environmental conditions they endure on a daily basis and have become more resistant to bleaching stress. In deeper sites that did exhibit higher bleaching (Mombasa and Nyali), it was found that coral recovery occurred more quickly in the protected area than in the non-protected area.

  6. In-Drift Microbial Communities

    Energy Technology Data Exchange (ETDEWEB)

    D. Jolley

    2000-11-09

    As directed by written work direction (CRWMS M and O 1999f), Performance Assessment (PA) developed a model for microbial communities in the engineered barrier system (EBS) as documented here. The purpose of this model is to assist Performance Assessment and its Engineered Barrier Performance Section in modeling the geochemical environment within a potential repository drift for TSPA-SR/LA, thus allowing PA to provide a more detailed and complete near-field geochemical model and to answer the key technical issues (KTI) raised in the NRC Issue Resolution Status Report (IRSR) for the Evolution of the Near Field Environment (NFE) Revision 2 (NRC 1999). This model and its predecessor (the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document, CRWMS M and O 1998a) was developed to respond to the applicable KTIs. Additionally, because of the previous development of the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document (CRWMS M and O 1998a), the M and O was effectively able to resolve a previous KTI concern regarding the effects of microbial processes on seepage and flow (NRC 1998). This document supercedes the in-drift microbial communities model as documented in Chapter 4 of the TSPA-VA Technical Basis Document (CRWMS M and O 1998a). This document provides the conceptual framework of the revised in-drift microbial communities model to be used in subsequent performance assessment (PA) analyses.

  7. Biogeochemistry of Microbial Mats

    Science.gov (United States)

    DesMarais, David J.; DeVincenizi, D. (Technical Monitor)

    2002-01-01

    The hierarchical organization of microbial ecosystems determines the rates of processes that shape Earth's environment, define the stage upon which major evolutionary events occurred, and create biosignatures in sediments and atmospheres. In cyanobacterial mats, oxygenic photosynthesis provides energy, organic substrates and oxygen to the ecosystem. Incident light changes with depth in the mat, both in intensity and spectral composition, and counteracting gradients of oxygen and sulfide shape the chemical microenvironment. A combination of benefits and hazards of light, oxygen and sulfide promotes the allocation of the various essential mat processes between light and dark periods and to various depths in the mat. Microliters produce hydrogen, small organic acids, nitrogen and sulfur species. Such compounds fuel a flow of energy and electrons in these ecosystems and thus shape interactions between groups of microorganisms. Coordinated observations of population distribution, abundance, and activity for an entire community are making fundamental questions in ecology accessible. These questions address those factors that sustain the remarkable diversity of microorganisms that are now being revealed by molecular techniques. These questions also target the processes that shape the various kinds of biosignatures that we will seek, both in ancient rocks from Earth and Mars, and in atmospheres of distant planets beyond our Solar System.

  8. Microbial production of biovanillin

    Directory of Open Access Journals (Sweden)

    A. Converti

    2010-10-01

    Full Text Available This review aims at providing an overview on the microbial production of vanillin, a new alternative method for the production of this important flavor of the food industry, which has the potential to become economically competitive in the next future. After a brief description of the applications of vanillin in different industrial sectors and of its physicochemical properties, we described the traditional ways of providing vanillin, specifically extraction and chemical synthesis (mainly oxidation and compared them with the new biotechnological options, i.e., biotransformations of caffeic acid, veratraldehyde and mainly ferulic acid. In the second part of the review, emphasis has been addressed to the factors most influencing the bioproduction of vanillin, specifically the age of inoculum, pH, temperature, type of co-substrate, as well as the inhibitory effects exerted either by excess substrate or product. The final part of the work summarized the downstream processes and the related unit operations involved in the recovery of vanillin from the bioconversion medium.

  9. Metagenomics of the deep Mediterranean, a warm bathypelagic habitat.

    Directory of Open Access Journals (Sweden)

    Ana-Belen Martín-Cuadrado

    Full Text Available BACKGROUND: Metagenomics is emerging as a powerful method to study the function and physiology of the unexplored microbial biosphere, and is causing us to re-evaluate basic precepts of microbial ecology and evolution. Most marine metagenomic analyses have been nearly exclusively devoted to photic waters. METHODOLOGY/PRINCIPAL FINDINGS: We constructed a metagenomic fosmid library from 3,000 m-deep Mediterranean plankton, which is much warmer (approximately 14 degrees C than waters of similar depth in open oceans (approximately 2 degrees C. We analyzed the library both by phylogenetic screening based on 16S rRNA gene amplification from clone pools and by sequencing both insert extremities of ca. 5,000 fosmids. Genome recruitment strategies showed that the majority of high scoring pairs corresponded to genomes from Rhizobiales within the Alphaproteobacteria, Cenarchaeum symbiosum, Planctomycetes, Acidobacteria, Chloroflexi and Gammaproteobacteria. We have found a community structure similar to that found in the aphotic zone of the Pacific. However, the similarities were significantly higher to the mesopelagic (500-700 m deep in the Pacific than to the single 4000 m deep sample studied at this location. Metabolic genes were mostly related to catabolism, transport and degradation of complex organic molecules, in agreement with a prevalent heterotrophic lifestyle for deep-sea microbes. However, we observed a high percentage of genes encoding dehydrogenases and, among them, cox genes, suggesting that aerobic carbon monoxide oxidation may be important in the deep ocean as an additional energy source. CONCLUSIONS/SIGNIFICANCE: The comparison of metagenomic libraries from the deep Mediterranean and the Pacific ALOHA water column showed that bathypelagic Mediterranean communities resemble more mesopelagic communities in the Pacific, and suggests that, in the absence of light, temperature is a major stratifying factor in the oceanic water column, overriding

  10. Gulf-Wide Information System, Environmental Sensitivity Index Habitats Database, Geographic NAD83, LDWF (2001) [esi_habitats_LDWF_2001

    Data.gov (United States)

    Louisiana Geographic Information Center — This data set contains sensitive biological resource data for coastal habitats in Louisiana. Vector polygons represent various habitats, including marsh types, other...

  11. Metagenomic analysis exploring taxonomic and functional diversity of soil microbial communities in Chilean vineyards and surrounding native forests

    Directory of Open Access Journals (Sweden)

    Luis E. Castañeda

    2017-03-01

    Full Text Available Mediterranean biomes are biodiversity hotspots, and vineyards are important components of the Mediterranean landscape. Over the last few decades, the amount of land occupied by vineyards has augmented rapidly, thereby increasing threats to Mediterranean ecosystems. Land use change and agricultural management have important effects on soil biodiversity, because they change the physical and chemical properties of soil. These changes may also have consequences on wine production considering that soil is a key component of terroir. Here, we describe the taxonomic diversity and metabolic functions of bacterial and fungal communities present in forest and vineyard soils in Chile. To accomplish this goal, we collected soil samples from organic vineyards in central Chile and employed a shotgun metagenomic approach to sequence the microbial DNA. Additionally, we studied the surrounding native forest to obtain a baseline of the soil conditions in the area prior to the establishment of the vineyard. Our metagenomic analyses revealed that both habitats shared most of the soil microbial species. The most abundant genera in the two habitats were the bacteria Candidatus Solibacter and Bradyrhizobium and the fungus Gibberella. Our results suggest that the soil microbial communities are similar in these forests and vineyards. Therefore, we hypothesize that native forests surrounding the vineyards may be acting as a microbial reservoir buffering the effects of the land conversion. Regarding the metabolic diversity, we found that genes pertaining to the metabolism of amino acids, fatty acids, and nucleotides as well as genes involved in secondary metabolism were enriched in forest soils. On the other hand, genes related to miscellaneous functions were more abundant in vineyard soils. These results suggest that the metabolic function of microbes found in these habitats differs, though differences are not related to taxonomy. Finally, we propose that the

  12. Metagenomic analysis exploring taxonomic and functional diversity of soil microbial communities in Chilean vineyards and surrounding native forests.

    Science.gov (United States)

    Castañeda, Luis E; Barbosa, Olga

    2017-01-01

    Mediterranean biomes are biodiversity hotspots, and vineyards are important components of the Mediterranean landscape. Over the last few decades, the amount of land occupied by vineyards has augmented rapidly, thereby increasing threats to Mediterranean ecosystems. Land use change and agricultural management have important effects on soil biodiversity, because they change the physical and chemical properties of soil. These changes may also have consequences on wine production considering that soil is a key component of terroir . Here, we describe the taxonomic diversity and metabolic functions of bacterial and fungal communities present in forest and vineyard soils in Chile. To accomplish this goal, we collected soil samples from organic vineyards in central Chile and employed a shotgun metagenomic approach to sequence the microbial DNA. Additionally, we studied the surrounding native forest to obtain a baseline of the soil conditions in the area prior to the establishment of the vineyard. Our metagenomic analyses revealed that both habitats shared most of the soil microbial species. The most abundant genera in the two habitats were the bacteria Candidatus Solibacter and Bradyrhizobium and the fungus Gibberella . Our results suggest that the soil microbial communities are similar in these forests and vineyards. Therefore, we hypothesize that native forests surrounding the vineyards may be acting as a microbial reservoir buffering the effects of the land conversion. Regarding the metabolic diversity, we found that genes pertaining to the metabolism of amino acids, fatty acids, and nucleotides as well as genes involved in secondary metabolism were enriched in forest soils. On the other hand, genes related to miscellaneous functions were more abundant in vineyard soils. These results suggest that the metabolic function of microbes found in these habitats differs, though differences are not related to taxonomy. Finally, we propose that the implementation of

  13. Toward Dynamic Ocean Management: Fisheries assessment and climate projections informed by community developed habitat models based on dynamic coastal oceanography

    Science.gov (United States)

    Kohut, J. T.; Manderson, J.; Palamara, L. J.; Saba, V. S.; Saba, G.; Hare, J. A.; Curchitser, E. N.; Moore, P.; Seibel, B.; DiDomenico, G.

    2016-12-01

    Through a multidisciplinary study group of experts in marine ecology, physical oceanography and stock assessment from the fishing industry, government and academia we developed a method to explicitly account for shifting habitat distributions in fish population assessments. We used data from field surveys throughout the Northwest Atlantic Ocean to develop a parametric thermal niche model for an important short-lived pelagic forage fish, Atlantic Butterfish. This niche model was coupled to a hindcast of daily bottom water temperature derived from a regional numerical ocean model in order to project daily thermal habitat suitability over the last 40 years. This ecological hindcast was used to estimate the proportion of thermal habitat suitability available on the U.S. Northeast Shelf that was sampled on fishery-independent surveys, accounting for the relative motions of thermal habitat and the trajectory of sampling on the survey. The method and habitat based estimates of availability was integrated into the catchability estimate used to scale population size in the butterfish stock assessment model accepted by the reviewers of the 59th NEFSC stock assessment review, as well as the mid-Atlantic Council's Scientific and Statistical Committee. The contribution of the availability estimate (along with an estimate of detectability) allowed for the development of fishery reference points, a change in stock status from unknown to known, and the establishment of a directed fishery with an allocation of 20,000 metric tons of quota. This presentation will describe how a community based workgroup utilized ocean observing technologies combined with ocean models to better understand the physical ocean that structures marine ecosystems. Using these approaches we will discuss opportunities to inform ecological hindcasts and climate projections with mechanistic models that link species-specific physiology to climate-based thermal scenarios.

  14. Differential sensitivity of total and active soil microbial communities to drought and forest management.

    Science.gov (United States)

    Bastida, Felipe; Torres, Irene F; Andrés-Abellán, Manuela; Baldrian, Petr; López-Mondéjar, Rubén; Větrovský, Tomáš; Richnow, Hans H; Starke, Robert; Ondoño, Sara; García, Carlos; López-Serrano, Francisco R; Jehmlich, Nico

    2017-10-01

    Climate change will affect semiarid ecosystems through severe droughts that increase the competition for resources in plant and microbial communities. In these habitats, adaptations to climate change may consist of thinning-that reduces competition for resources through a decrease in tree density and the promotion of plant survival. We deciphered the functional and phylogenetic responses of the microbial community to 6 years of drought induced by rainfall exclusion and how forest management affects its resistance to drought, in a semiarid forest ecosystem dominated by Pinus halepensis Mill. A multiOMIC approach was applied to reveal novel, community-based strategies in the face of climate change. The diversity and the composition of the total and active soil microbiome were evaluated by 16S rRNA gene (bacteria) and ITS (fungal) sequencing, and by metaproteomics. The microbial biomass was analyzed by phospholipid fatty acids (PLFAs), and the microbially mediated ecosystem multifunctionality was studied by the integration of soil enzyme activities related to the cycles of C, N, and P. The microbial biomass and ecosystem multifunctionality decreased in drought-plots, as a consequence of the lower soil moisture and poorer plant development, but this decrease was more notable in unthinned plots. The structure and diversity of the total bacterial community was unaffected by drought at phylum and order level, but did so at genus level, and was influenced by seasonality. However, the total fungal community and the active microbial community were more sensitive to drought and were related to ecosystem multifunctionality. Thinning in plots without drought increased the active diversity while the total diversity was not affected. Thinning promoted the resistance of ecosystem multifunctionality to drought through changes in the active microbial community. The integration of total and active microbiome analyses avoids misinterpretations of the links between the soil microbial

  15. Microbial lipids reveal carbon assimilation patterns on hydrothermal sulfide chimneys.

    Science.gov (United States)

    Reeves, Eoghan P; Yoshinaga, Marcos Y; Pjevac, Petra; Goldenstein, Nadine I; Peplies, Jörg; Meyerdierks, Anke; Amann, Rudolf; Bach, Wolfgang; Hinrichs, Kai-Uwe

    2014-11-01

    Sulfide 'chimneys' characteristic of seafloor hydrothermal venting are diverse microbial habitats. ¹³C/¹²C ratios of microbial lipids have rarely been used to assess carbon assimilation pathways on these structures, despite complementing gene- and culture-based approaches. Here, we integrate analyses of the diversity of intact polar lipids (IPL) and their side-chain δ¹³C values (δ¹³ C(lipid)) with 16S rRNA gene-based phylogeny to examine microbial carbon flow on active and inactive sulfide structures from the Manus Basin. Surficial crusts of active structures, dominated by Epsilonproteobacteria, yield bacterial δ¹³C(lipid) values higher than biomass δ¹³C (total organic carbon), implicating autotrophy via the reverse tricarboxylic acid cycle. Our data also suggest δ¹³C(lipid) values vary on individual active structures without accompanying microbial diversity changes. Temperature and/or dissolved substrate effects - likely relating to variable advective-diffusive fluxes to chimney exteriors - may be responsible for differing ¹³C fractionation during assimilation. In an inactive structure, δ¹³C(lipid) values lower than biomass δ¹³C and a distinctive IPL and 16S rRNA gene diversity suggest a shift to a more diverse community and an alternate carbon assimilation pathway after venting ceases. We discuss here the potential of IPL and δ¹³C(lipid) analyses to elucidate carbon flow in hydrothermal structures when combined with other molecular tools. © 2014 Society for Applied Microbiology and John Wiley & Sons Ltd.

  16. Wildlife Habitat Models for Terrestrial Vertebrates

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The project developed habitat capability models for representative wildlife species. It was part of a project led by the University of Massachusetts Amherst to...

  17. Avian Habitat Data; Seward Peninsula, Alaska, 2012

    Data.gov (United States)

    Department of the Interior — This data product contains avian habitat data collected on the Seward Peninsula, Alaska, USA, during 21 May – 10 June 2012. We conducted replicated 10-min surveys...

  18. Exploring Habitat Selection by Wildlife with adehabitat

    Directory of Open Access Journals (Sweden)

    Clément Calenge

    2007-07-01

    Full Text Available Knowledge of the environmental features affecting habitat selection by animals is important for designing wildlife management and conservation policies. The package adehabitat for the R software is designed to provide a computing environment for the analysis and modelling of such relationships. This paper focuses on the preliminary steps of data exploration and analysis, performed prior to a more formal modelling of habitat selection. In this context, I illustrate the use of a factorial analysis, the K-select analysis. This method is a factorial decomposition of marginality, one measure of habitat selection. This method was chosen to present the package because it illustrates clearly many of its features (home range estimation, spatial analyses, graphical possibilities, etc.. I strongly stress the powerful capabilities of factorial methods for data analysis, using as an example the analysis of habitat selection by the wild boar (Sus scrofa L. in a Mediterranean environment.

  19. Final Critical Habitat for the Noel's Amphipod

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Noel's amphipod occur. The geographic extent includes Chaves County, New Mexico.

  20. Final Critical Habitat (Charadrius melodus) 20090519

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — These data identify, in general, the areas of FINAL critical habitat for Charadrius melodus (piping plover (wintering population)) based on descriptions provided in...

  1. Mining, habitats lead space architecture work

    National Research Council Canada - National Science Library

    David Nixon

    2013-01-01

      Nixon narrates how space mining habitats lead space architecture work. NASA's current focus on an asteroid rendezvous mission as human space exploration's next big goal has begun to stimulate ideas from the space community at large...

  2. Seabirds in marine habitats of southeast Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers seabirds in marine habitats of southeast Alaska. The methods, study areas (ocean, shelf break, continental shelf, and inland passage waters) and...

  3. Deep-Sea Soft Coral Habitat Suitability

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deep-sea corals, also known as cold water corals, create complex communities that provide habitat for a variety of invertebrate and fish species, such as grouper,...

  4. Waterfowl Breeding Population and Habitat Survey

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The Waterfowl Breeding Population and Habitat Survey was initiated experimentally in 1947 and became operational in 1955. It is conducted cooperatively by the U.S....

  5. Kulm Wetland Management District Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The purpose of this habitat management plan (HMP) is to provide a strategic plan for consistently and effectively protecting, acquiring, enhancing, restoring, and...

  6. Self-Deploying, Composite Habitats Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group, Inc. (CRG), proposes to develop self-deploying, composite structures for lunar habitats, based on CRG's VeritexTM materials. These...

  7. Self-Deploying, Composite Habitats Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Cornerstone Research Group, Inc. (CRG), proposes to develop self-deploying, composite structures for lunar habitats, based on CRG's Veritex(TM) materials. These...

  8. Deep-Sea Stony Coral Habitat Suitability

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Deep-sea corals, also known as cold water corals, create complex communities that provide habitat for a variety of invertebrate and fish species, such as grouper,...

  9. Ecosystem services Linking People to Coastal Habitats.

    Science.gov (United States)

    Given the growing desire to incorporate ecosystem goods and services (EGS) considerations into coastal planning efforts, it is imperative that stakeholders understand how coastal habitats affect the availability and delivery of those EGS. Nonetheless, methods requiring long-term ...

  10. Habitat--Offshore Pigeon Point, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Pigeon Point map area, California. The vector data file is included in...

  11. Habitat--Offshore Santa Cruz, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Santa Cruz map area, California. The vector data file is included in...

  12. Habitat--Offshore of Aptos, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Aptos map area, California. The vector data file is included in...

  13. Habitat--Offshore Scott Creek, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Scott Creek map area, California. The vector data file is included in...

  14. Habitat--Monterey Canyon and Vicinity, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Monterey Canyon and Vicinity map area, California. The vector data file is included in...

  15. Habitat Mapping Cruise (HB0805, EK60)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Objectives are to: 1) perform multibeam mapping of transitional and deepwater habitats in Hudson Canyon (off New Jersey) with the National Institute of Undersea...

  16. Habitat Testbed (HaT) Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Goals of the DSH Testbed include:Function as a habitat systems integrator and technology pull across many domainsDevelop and integrate software-based models of...

  17. Concept Plan for Waterfowl Habitat Protection

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — The San Francisco Bay Area is one of 34 Waterfowl Habitat Areas of Major Concern (#27) in Canada and the United States identified in the North American Waterfowl...

  18. Final Critical Habitat for the Koster's Springsnail

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — To provide the user with a general idea of areas where final critical habitat for Koster's springsnail occur. The geographic extent includes Chaves County, New Mexico.

  19. Klawock Lagoon, Alaska Benthic Habitats 2011 Substrate

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  20. Klawock Lagoon, Alaska Benthic Habitats 2011 Geoform

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  1. Klawock Lagoon, Alaska Benthic Habitats 2011 Geodatabase

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  2. Klawock Lagoon, Alaska Benthic Habitats 2011 Biotic

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Klawock River on Alaska's Prince of Wales Island drains a 29,061 acre watershed with 132 miles of streambed habitat supporting seven salmon and trout species....

  3. Riparian Habitats - Sierra Nevada Foothill [ds304

    Data.gov (United States)

    California Department of Resources — These data are habitat polygons within a 200-m radius around point locations where wildlife surveys were conducted along 19 randomly selected watercourses in the...

  4. Expandable/Foldable Structures for Habitat Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Folded Structures Company (FSC) proposes the development of an innovative design approach for multi-laminate, primary and secondary structures for planetary habitats...

  5. Habitat--Offshore of San Francisco, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of San Francisco map area, California. The vector data file is included in...

  6. Habitat--Offshore of Tomales Point, California

    Data.gov (United States)

    U.S. Geological Survey, Department of the Interior — This part of DS 781 presents data for the habitat map of the seafloor of the Offshore of Tomales Point map area, California. The polygon shapefile is included in...

  7. Elkhorn and Staghorn Corals Critical Habitat

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data represent the critical habitat for elkhorn coral (Acropora palmata) and staghorn coral (A. cervicornis) as designated by 73 FR 72210, November 26, 2008,...

  8. Dahomey National Wildlife Refuge Habitat Management Plan

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Habitat management for Dahomey National Wildife Refuge for the next 10-15 years is outlined and disucsses goals and objectives from the N. MS Refuge Complex CCP and...

  9. Performance of microbial phytases for gastric inositol phosphate degradation

    DEFF Research Database (Denmark)

    Nielsen, Anne Veller Friis; Nyffenegger, Christian; Meyer, Anne S.

    2015-01-01

    Microbial phytases catalyze dephosphorylation of phytic acid, thereby potentially releasing chelated iron and improving human iron absorption from cereal-based diets. For this catalysis to take place in vivo, the phytase must be robust to low pH and proteolysis in the gastric ventricle. This study...... compares the robustness of five different microbial phytases, evaluating thermal stability, activity retention, and extent of dephosphorylation of phytic acid in a simulated low-pH/pepsin gastric environment and examines secondary protein structural changes at low pH via circular dichroism. The Peniophora...... lycii phytase was found to be the most thermostable, but the least robust enzyme in gastric conditions, whereas the Aspergillus niger and Escherichia coli phytases proved to be most resistant to gastric conditions. The phytase from Citrobacter braakii showed intermediate robustness. The extent of loss...

  10. Influence of coral and algal exudates on microbially mediated reef metabolism

    Directory of Open Access Journals (Sweden)

    Andreas F. Haas

    2013-07-01

    Full Text Available Benthic primary producers in tropical reef ecosystems can alter biogeochemical cycling and microbial processes in the surrounding seawater. In order to quantify these influences, we measured rates of photosynthesis, respiration, and dissolved organic carbon (DOC exudate release by the dominant benthic primary producers (calcifying and non-calcifying macroalgae, turf-algae and corals on reefs of Mo‘orea French Polynesia. Subsequently, we examined planktonic and benthic microbial community response to these dissolved exudates by measuring bacterial growth rates and oxygen and DOC fluxes in dark and daylight incubation experiments. All benthic primary producers exuded significant quantities of DOC (roughly 10% of their daily fixed carbon into the surrounding water over a diurnal cycle. The microbial community responses were dependent upon the source of the exudates and whether the inoculum of microbes included planktonic or planktonic plus benthic communities. The planktonic and benthic microbial communities in the unamended control treatments exhibited opposing influences on DO concentration where respiration dominated in treatments comprised solely of plankton and autotrophy dominated in treatments with benthic plus plankon microbial communities. Coral exudates (and associated inorganic nutrients caused a shift towards a net autotrophic microbial metabolism by increasing the net production of oxygen by the benthic and decreasing the net consumption of oxygen by the planktonic microbial community. In contrast, the addition of algal exudates decreased the net primary production by the benthic communities and increased the net consumption of oxygen by the planktonic microbial community thereby resulting in a shift towards net heterotrophic community metabolism. When scaled up to the reef habitat, exudate-induced effects on microbial respiration did not outweigh the high oxygen production rates of benthic algae, such that reef areas dominated with

  11. An interpolation method for stream habitat assessments

    Science.gov (United States)

    Sheehan, Kenneth R.; Welsh, Stuart A.

    2015-01-01

    Interpolation of stream habitat can be very useful for habitat assessment. Using a small number of habitat samples to predict the habitat of larger areas can reduce time and labor costs as long as it provides accurate estimates of habitat. The spatial correlation of stream habitat variables such as substrate and depth improves the accuracy of interpolated data. Several geographical information system interpolation methods (natural neighbor, inverse distance weighted, ordinary kriging, spline, and universal kriging) were used to predict substrate and depth within a 210.7-m2 section of a second-order stream based on 2.5% and 5.0% sampling of the total area. Depth and substrate were recorded for the entire study site and compared with the interpolated values to determine the accuracy of the predictions. In all instances, the 5% interpolations were more accurate for both depth and substrate than the 2.5% interpolations, which achieved accuracies up to 95% and 92%, respectively. Interpolations of depth based on 2.5% sampling attained accuracies of 49–92%, whereas those based on 5% percent sampling attained accuracies of 57–95%. Natural neighbor interpolation was more accurate than that using the inverse distance weighted, ordinary kriging, spline, and universal kriging approaches. Our findings demonstrate the effective use of minimal amounts of small-scale data for the interpolation of habitat over large areas of a stream channel. Use of this method will provide time and cost savings in the assessment of large sections of rivers as well as functional maps to aid the habitat-based management of aquatic species.

  12. Columbia County Habitat for Humanity Passive Townhomes

    Energy Technology Data Exchange (ETDEWEB)

    None, None

    2016-03-01

    Columbia County Habitat for Humanity (CCHH) (New York, Climate Zone 5A) built a pair of townhomes to Passive House Institute U.S. (PHIUS+ 2015) criteria to explore approaches for achieving Passive House performance (specifically with respect to exterior wall, space-conditioning, and ventilation strategies) within the labor and budget context inherent in a Habitat for Humanity project. CCHH’s goal is to eventually develop a cost-justified Passive House prototype design for future projects.

  13. Optimal Economic Landscapes with Habitat Fragmentation Effects

    OpenAIRE

    Lewis, David J.; Wu, JunJie

    2005-01-01

    Habitat fragmentation is widely considered a primary threat to biodiversity. This paper develops a theoretical model of land use to analyze the optimal conservation of landscapes when land quality is spatially heterogeneous and wildlife habitat is fragmented and socially valuable. When agriculture is the primary cause of fragmentation, we show that reforestation efforts should be targeted to the most fragmented landscapes with an aggregate share of forest equal to a threshold, defined by the ...

  14. Seasonal thermal energy storage

    Energy Technology Data Exchange (ETDEWEB)

    Allen, R.D.; Kannberg, L.D.; Raymond, J.R.

    1984-05-01

    This report describes the following: (1) the US Department of Energy Seasonal Thermal Energy Storage Program, (2) aquifer thermal energy storage technology, (3) alternative STES technology, (4) foreign studies in seasonal thermal energy storage, and (5) economic assessment.

  15. Lunar Habitat Optimization Using Genetic Algorithms

    Science.gov (United States)

    SanScoucie, M. P.; Hull, P. V.; Tinker, M. L.; Dozier, G. V.

    2007-01-01

    Long-duration surface missions to the Moon and Mars will require bases to accommodate habitats for the astronauts. Transporting the materials and equipment required to build the necessary habitats is costly and difficult. The materials chosen for the habitat walls play a direct role in protection against each of the mentioned hazards. Choosing the best materials, their configuration, and the amount required is extremely difficult due to the immense size of the design region. Clearly, an optimization method is warranted for habitat wall design. Standard optimization techniques are not suitable for problems with such large search spaces; therefore, a habitat wall design tool utilizing genetic algorithms (GAs) has been developed. GAs use a "survival of the fittest" philosophy where the most fit individuals are more likely to survive and reproduce. This habitat design optimization tool is a multiobjective formulation of up-mass, heat loss, structural analysis, meteoroid impact protection, and radiation protection. This Technical Publication presents the research and development of this tool as well as a technique for finding the optimal GA search parameters.

  16. Salmon River Habitat Enhancement, 1989 Annual Report.

    Energy Technology Data Exchange (ETDEWEB)

    Rowe, Mike

    1989-04-01

    This project was funded by the Bonneville Power Administration (BPA). The annual report contains three individual subproject papers detailing tribal fisheries work completed during the summer and fall of 1989. Subproject 1 contains summaries of evaluation/monitoring efforts associated with the Bear Valley Creek, Idaho enhancement project. Subproject 2 contains an evaluation of the Yankee Fork of the Salmon River habitat enhancement project. This report has been sub-divided into two parts: Part 1; stream evaluation and Part 2; pond series evaluation. Subproject 3 concerns the East Fork of the Salmon River, Idaho. This report summarizes the evaluation of the project to date including the 1989 pre-construction evaluation conducted within the East Fork drainage. Dredge mining has degraded spawning and rearing habitat for chinook salmon and steelhead trout in the Yankee Fork drainage of the Salmon River and in Bear Valley Creek. Mining, agricultural, and grazing practices degraded habitat in the East Fork of the Salmon River. Biological monitoring of the success of habitat enhancement for Bear Valley Creek and Yankee Fork are presented in this report. Physical and biological inventories prior to habitat enhancement in East Fork were also conducted. Four series of off-channel ponds of the Yankee Fork are shown to provide effective rearing habitat for chinook salmon. 45 refs., 49 figs., 24 tabs.

  17. Fundamentals of Thermal Expansion and Thermal Contraction

    OpenAIRE

    Liu, Zi-Kui; Shang, Shun-Li; Wang, Yi

    2017-01-01

    Thermal expansion is an important property of substances. Its theoretical prediction has been challenging, particularly in cases the volume decreases with temperature, i.e., thermal contraction or negative thermal expansion at high temperatures. In this paper, a new theory recently developed by the authors has been reviewed and further examined in the framework of fundamental thermodynamics and statistical mechanics. Its applications to cerium with colossal thermal expansion and Fe3Pt with th...

  18. The compost bomb: thermal instability in peatland soils

    Science.gov (United States)

    Luke, C. M.; Cox, P. M.

    2009-04-01

    A simple model is constructed to investigate the effect of thermal energy generated by microbial respiration on soil temperature and soil carbon stocks, specifically in peat soils. Stability analysis shows a potential tipping point in the system beyond which a sudden large increase in soil temperature and decrease in soil carbon is predicted. Stability of the system depends on a dimensionless number, itself dependent on the effective soil thermal conductivity and the temperature sensitivity of microbial respiration. The influence of soil moisture on the effective thermal conductivity, and therefore the stability of the system, is also investigated. These results suggest that peatland soils insulated by a moss or lichen layer are potentially destabilised under certain conditions of warming and drying.

  19. Beyond the border: effects of an expanding algal habitat on the fauna of neighbouring habitats.

    Science.gov (United States)

    Lanham, Brendan S; Gribben, Paul E; Poore, Alistair G B

    2015-05-01

    The impacts of novel habitat-forming organisms on associated fauna have been difficult to predict, and may affect the fauna of neighbouring habitats due to changes in the spatial configuration of habitat patches of differing quality. Here, we test whether the localised expansion of a native habitat-forming macroalga, Caulerpa filiformis, on subtidal reefs can affect the abundance of fauna associated with a neighbouring macroalgal habitat. C. filiformis was a functionally distinct habitat for fauna, and the total abundance of epifauna associated with the resident alga, Sargassum linearifolium, was reduced at some sites when in close proximity to or surrounded by C. filiformis. Experimental manipulation of habitat configuration demonstrated that the low abundance of gastropods on S. linearifolium when surrounded by C. filiformis was likely explained by C. filiformis acting as a physical dispersal barrier for mobile fauna. Changes to the spatial configuration of novel and resident habitats can thus affect the abundance of fauna in addition to the direct replacement of habitats by species undergoing range expansions or increasing in abundance. Copyright © 2015 Elsevier Ltd. All rights reserved.

  20. [Microbial geochemical calcium cycle].

    Science.gov (United States)

    Zavarzin, G A

    2002-01-01

    The participation of microorganisms in the geochemical calcium cycle is the most important factor maintaining neutral conditions on the Earth. This cycle has profound influence on the fate of inorganic carbon, and, thereby, on the removal of CO2 from the atmosphere. The major part of calcium deposits was formed in the Precambrian, when prokaryotic biosphere predominated. After that, calcium recycling based on biogenic deposition by skeletal organisms became the main process. Among prokaryotes, only a few representatives, e.g., cyanobacteria, exhibit a special calcium function. The geochemical calcium cycle is made possible by the universal features of bacteria involved in biologically mediated reactions and is determined by the activities of microbial communities. In the prokaryotic system, the calcium cycle begins with the leaching of igneous rock predominantly through the action of the community of organotrophic organisms. The release of carbon dioxide to the soil air by organotrophic aerobes leads to leaching with carbonic acid and soda salinization. Under anoxic conditions, of major importance is the organic acid production by primary anaerobes (fermentative microorganisms). Calcium carbonate is precipitated by secondary anaerobes (sulfate reducers) and to a smaller degree by methanogens. The role of the cyanobacterial community in carbonate deposition is exposed by stromatolites, which are the most common organo-sedimentary Precambrian structures. Deposition of carbonates in cyanobacterial mats as a consequence of photoassimilation of CO2 does not appear to be a significant process. It is argued that carbonates were deposited at the boundary between the "soda continent", which emerged as a result of subaerial leaching with carbonic acid, and the ocean containing Ca2+. Such ecotones provided favorable conditions for the development of the benthic cyanobacterial community, which was a precursor of stromatolites.

  1. Thermal carrying capacity for a thermally-sensitive species at the warmest edge of its range.

    Directory of Open Access Journals (Sweden)

    Daniel Ayllón

    Full Text Available Anthropogenic environmental change is causing unprecedented rates of population extirpation and altering the setting of range limits for many species. Significant population declines may occur however before any reduction in range is observed. Determining and modelling the factors driving population size and trends is consequently critical to predict trajectories of change and future extinction risk. We tracked during 12 years 51 populations of a cold-water fish species (brown trout Salmo trutta living along a temperature gradient at the warmest thermal edge of its range. We developed a carrying capacity model in which maximum population size is limited by physical habitat conditions and regulated through territoriality. We first tested whether population numbers were driven by carrying capacity dynamics and then targeted on establishing (1 the temperature thresholds beyond which population numbers switch from being physical habitat- to temperature-limited; and (2 the rate at which carrying capacity declines with temperature within limiting thermal ranges. Carrying capacity along with emergent density-dependent responses explained up to 76% of spatio-temporal density variability of juveniles and adults but only 50% of young-of-the-year's. By contrast, young-of-the-year trout were highly sensitive to thermal conditions, their performance declining with temperature at a higher rate than older life stages, and disruptions being triggered at lower temperature thresholds. Results suggest that limiting temperature effects were progressively stronger with increasing anthropogenic disturbance. There was however a critical threshold, matching the incipient thermal limit for survival, beyond which realized density was always below potential numbers irrespective of disturbance intensity. We additionally found a lower threshold, matching the thermal limit for feeding, beyond which even unaltered populations declined. We predict that most of our study

  2. Comparison of bacterial communities from lava cave microbial mats to overlying surface soils from Lava Beds National Monument, USA.

    Science.gov (United States)

    Lavoie, Kathleen H; Winter, Ara S; Read, Kaitlyn J H; Hughes, Evan M; Spilde, Michael N; Northup, Diana E

    2017-01-01

    Subsurface habitats harbor novel diversity that has received little attention until recently. Accessible subsurface habitats include lava caves around the world that often support extensive microbial mats on ceilings and walls in a range of colors. Little is known about lava cave microbial diversity and how these subsurface mats differ from microbial communities in overlying surface soils. To investigate these differences, we analyzed bacterial 16S rDNA from 454 pyrosequencing from three colors of microbial mats (tan, white, and yellow) from seven lava caves in Lava Beds National Monument, CA, USA, and compared them with surface soil overlying each cave. The same phyla were represented in both surface soils and cave microbial mats, but the overlap in shared OTUs (operational taxonomic unit) was only 11.2%. Number of entrances per cave and temperature contributed to observed differences in diversity. In terms of species richness, diversity by mat color differed, but not significantly. Actinobacteria dominated in all cave samples, with 39% from caves and 21% from surface soils. Proteobacteria made up 30% of phyla from caves and 36% from surface soil. Other major phyla in caves were Nitrospirae (7%) followed by minor phyla (7%), compared to surface soils with Bacteroidetes (8%) and minor phyla (8%). Many of the most abundant sequences could not be identified to genus, indicating a high degree of novelty. Surface soil samples had more OTUs and greater diversity indices than cave samples. Although surface soil microbes immigrate into underlying caves, the environment selects for microbes able to live in the cave habitats, resulting in very different cave microbial communities. This study is the first comprehensive comparison of bacterial communities in lava caves with the overlying soil community.

  3. The molecular dimension of microbial species: 1. Ecological distinctions among, and homogeneity within, putative ecotypes of Synechococcus inhabiting the cyanobacterial mat of Mushroom Spring, Yellowstone National Park

    DEFF Research Database (Denmark)

    Becraft, Eric D.; Wood, Jason M.; Rusch, Douglas B.

    2015-01-01

    and transcripts over a large number of habitat types in the Mushroom Spring microbial mat. Putative ecological species [putative ecotypes (PEs)], which were predicted by an evolutionary simulation based on the Stable Ecotype Model (Ecotype Simulation), exhibited distinct distributions relative to temperature...

  4. Microbial ecology of extreme environments: Antarctic yeasts and growth in substrate-limited habitats

    Science.gov (United States)

    Vishniac, H. S.

    1985-01-01

    The high, dry valleys of the Ross Desert of Antarctic, characterized by extremely low temperatures, aridity and a depauperate biota, are used as an analog of the postulated extreme climates of other planetary bodies of the Solar System to test the hypothesis that if life could be supported by Ross, it might be possible where similar conditions prevail. The previously considered sterility of the Ross Desert soil ecosystem has yielded up an indigenous yeast, Cryptoccus vishniacci, which is able to resist the extremes of cold, wet and dry freezing, and long arid periods, while making minimal nutritional demands on the soil.

  5. Geese are directing the plant and microbial communities of their arctic forage habitat

    NARCIS (Netherlands)

    Loonen, Maarten; Fivez, Lise; Teuchies, Johannes; Boon, Nico; Meire, Patrick

    2014-01-01

    The presented study aims to add more field evidence of goose grazing impact on the structure of Arctic ecosystems, which is necessary to better understand the effect of rising goose numbers on complex ecosystem processes. The conducted research made use of long-term exclosures on Svalbard to study

  6. Searches for Microbial Cells with Fluorescence Loggers with Single-cell Sensitivity

    Science.gov (United States)

    Price, P. B.; Rohde, R. A.; Bay, R. C.

    2007-12-01

    Two known habitats for microbial metabolism in ice are surfaces of mineral grains and liquid veins along three- grain boundaries. Several problems suggest the need for a third habitat: veins usually contain toxic liquid; some microorganisms are too large to fit into a vein; veins may not be present at all depths; and the oxygen concentration in veins does not permit the coexistence of both strict anaerobes and aerobes in the same region. We show that a more general habitat avoids these problems. Isolated microbes frozen in ice and not in contact with a vein or grain can metabolize by redox reactions with dissolved small molecules diffusing through the ice lattice. The two requirements are that the gaseous reactants have sufficiently high equilibrium concentrations and diffusion coefficients to provide enough metabolic energy to repair macromolecular damage as it occurs. Molecules with less than ~6 atoms (e.g., H2, O2, N2¬, CO, CO2, CH4, H2S, NH3, HNO3, HCHO, and HCOOH) have values of diffusion coefficient D(T) that exceed ~10- 15 m2 s-1, which is sufficient to sustain microbial life in ice. For terrestrial environments, we show that there is an adequate supply of such molecules diffusing throughout deep glacial ice to sustain metabolism for millions of years. Our recent noninvasive observations of ice cores from GISP2 and WAIS Divide provide evidence for this habitat. Using scanning fluorimetry to map proteins (a proxy for cells) and F420 (a proxy for methanogens) in ice cores, we find isolated spikes of fluorescence consistent with as few as one microbial cell in a volume 0.16 microliter with the protein mapper and in 1.9 microliter with the methanogen mapper. With such precise localization one could use a nanomanipulator to extract single cells for molecular identification. Low- power, miniaturized versions of these instruments could search for single cells in subglacial lakes, Martian ice- rich permafrost, and Europan ice.

  7. Functional diversity of the microbial community in healthy subjects and periodontitis patients based on sole carbon source utilization.

    Directory of Open Access Journals (Sweden)

    Yifei Zhang

    Full Text Available Chronic periodontitis is one of the most common forms of biofilm-induced diseases. Most of the recent studies were focus on the dental plaque microbial diversity and microbiomes. However, analyzing bacterial diversity at the taxonomic level alone limits deeper comprehension of the ecological relevance of the community. In this study, we compared the metabolic functional diversity of the microbial community in healthy subjects and periodontitis patients in a creative way--to assess the sole carbon source utilization using Biolog assay, which was first applied on oral micro-ecology assessment. Pattern analyses of 95-sole carbon sources catabolism provide a community-level phenotypic profile of the microbial community from different habitats. We found that the microbial community in the periodontitis group had greater metabolic activity compared to the microbial community in the healthy group. Differences in the metabolism of specific carbohydrates (e.g. β-methyl-D-glucoside, stachyose, maltose, D-mannose, β-methyl-D-glucoside and pyruvic acid were observed between the healthy and periodontitis groups. Subjects from the healthy and periodontitis groups could be well distinguished by cluster and principle component analyses according to the utilization of discriminate carbon sources. Our results indicate significant difference in microbial functional diversity between healthy subjects and periodontitis patients. We also found Biolog technology is effective to further our understanding of community structure as a composite of functional abilities, and it enables the identification of ecologically relevant functional differences among oral microbial communities.

  8. Pairing success of Kirtland's warblers in marginal vs. suitable habitat

    Science.gov (United States)

    John R. Probst; Jack P. Hayes

    1987-01-01

    We compared pairing success of male Kirtland's Warblers (Dendroica kirtlandii) in different habitats to test the hypothesis that a lower proportion of males in marginal habitat are mated. Fewer than 60% of the males in marginal habitat were paired, but 95% of the males in suitable habitat were paired. We estimated the overall pairing success of...

  9. Anthropogenic areas as incidental substitutes for original habitat.

    Science.gov (United States)

    Martínez-Abraín, Alejandro; Jiménez, Juan

    2016-06-01

    One speaks of ecological substitutes when an introduced species performs, to some extent, the ecosystem function of an extirpated native species. We suggest that a similar case exists for habitats. Species evolve within ecosystems, but habitats can be destroyed or modified by natural and human-made causes. Sometimes habitat alteration forces animals to move to or remain in a suboptimal habitat type. In that case, the habitat is considered a refuge, and the species is called a refugee. Typically refugee species have lower population growth rates than in their original habitats. Human action may lead to the unintended generation of artificial or semiartificial habitat types that functionally resemble the essential features of the original habitat and thus allow a population growth rate of the same magnitude or higher than in the original habitat. We call such areas substitution habitats and define them as human-made habitats within the focal species range that by chance are partial substitutes for the species' original habitat. We call species occupying a substitution habitat adopted species. These are 2 new terms in conservation biology. Examples of substitution habitats are dams for European otters, wheat and rice fields for many steppeland and aquatic birds, and urban areas for storks, falcons, and swifts. Although substitution habitats can bring about increased resilience against the agents of global change, the conservation of original habitat types remains a conservation priority. © 2016 Society for Conservation Biology.

  10. NEKTON-HABITAT ASSOCIATIONS IN YAQUINA BAY, OREGON

    Science.gov (United States)

    Habitat-based ecological risk assessments rely, in part, on estimates of the ecological value of the habitats at risk. To estimate estuarine habitat values with respect to the nekton (small fish, crabs and other invertebrates), we determined nekton-habitat associations in four i...

  11. Habitat connectivity and fragmented nuthatch populations in agricultural landscapes

    NARCIS (Netherlands)

    Langevelde, van F.

    1999-01-01

    In agricultural landscapes, the habitat of many species is subject to fragmentation. When the habitat of a species is fragmented and the distances between patches of habitat are large relative to the movement distances of the species, it can be expected that the degree of habitat

  12. Habitat fragmentation in the temperate zone: a perspective for managers

    Science.gov (United States)

    John Faaborg; Margaret Brittingham; Therese Donovan; John Blake

    1993-01-01

    Habitat fragmentation occurs when a large, fairly continuous tract of vegetation is converted to other vegetation types such that only scattered fragments of the original type remain. Problems associated with habitat fragmentation include overall habitat loss, increase in edge habitat and edge effects (particularly higher parasitism and nest predation rates), and...

  13. Forest habitat loss, fragmentation, and red-cockaded woodpecker populations

    Science.gov (United States)

    Richard N. Conner; D. Craig Rudolph

    1991-01-01

    Loss of mature forest habitat was measured around Red-cockaded Woodpecker (Picoides borealis) cavity tree clusters (colonies) in three National Forests in eastern Texas. Forest removal results in a loss of foraging habitat and causes habitat fragmentation of the remaining mature forest. Habitat loss was negatively associated with woodpecker group size in small...

  14. Links between plant and fungal diversity in habitat fragments of coastal shrubland.

    Science.gov (United States)

    Maltz, Mia R; Treseder, Kathleen K; McGuire, Krista L

    2017-01-01

    Habitat fragmentation is widespread across ecosystems, detrimentally affecting biodiversity. Although most habitat fragmentation studies have been conducted on macroscopic organisms, microbial communities and fungal processes may also be threatened by fragmentation. This study investigated whether fragmentation, and the effects of fragmentation on plants, altered fungal diversity and function within a fragmented shrubland in southern California. Using fluorimetric techniques, we assayed enzymes from plant litter collected from fragments of varying sizes to investigate enzymatic responses to fragmentation. To isolate the effects of plant richness from those of fragment size on fungi, we deployed litter bags containing different levels of plant litter diversity into the largest fragment and incubated in the field for one year. Following field incubation, we determined litter mass loss and conducted molecular analyses of fungal communities. We found that leaf-litter enzyme activity declined in smaller habitat fragments with less diverse vegetation. Moreover, we detected greater litter mass loss in litter bags containing more diverse plant litter. Additionally, bags with greater plant litter diversity harbored greater numbers of fungal taxa. These findings suggest that both plant litter resources and fungal function may be affected by habitat fragmentation's constraints on plants, possibly because plant species differ chemically, and may thus decompose at different rates. Diverse plant assemblages may produce a greater variety of litter resources and provide more ecological niche space, which may support greater numbers of fungal taxa. Thus, reduced plant diversity may constrain both fungal taxa richness and decomposition in fragmented coastal shrublands. Altogether, our findings provide evidence that even fungi may be affected by human-driven habitat fragmentation via direct effects of fragmentation on plants. Our findings underscore the importance of restoring

  15. Links between plant and fungal diversity in habitat fragments of coastal shrubland.

    Directory of Open Access Journals (Sweden)

    Mia R Maltz

    Full Text Available Habitat fragmentation is widespread across ecosystems, detrimentally affecting biodiversity. Although most habitat fragmentation studies have been conducted on macroscopic organisms, microbial communities and fungal processes may also be threatened by fragmentation. This study investigated whether fragmentation, and the effects of fragmentation on plants, altered fungal diversity and function within a fragmented shrubland in southern California. Using fluorimetric techniques, we assayed enzymes from plant litter collected from fragments of varying sizes to investigate enzymatic responses to fragmentation. To isolate the effects of plant richness from those of fragment size on fungi, we deployed litter bags containing different levels of plant litter diversity into the largest fragment and incubated in the field for one year. Following field incubation, we determined litter mass loss and conducted molecular analyses of fungal communities. We found that leaf-litter enzyme activity declined in smaller habitat fragments with less diverse vegetation. Moreover, we detected greater litter mass loss in litter bags containing more diverse plant litter. Additionally, bags with greater plant litter diversity harbored greater numbers of fungal taxa. These findings suggest that both plant litter resources and fungal function may be affected by habitat fragmentation's constraints on plants, possibly because plant species differ chemically, and may thus decompose at different rates. Diverse plant assemblages may produce a greater variety of litter resources and provide more ecological niche space, which may support greater numbers of fungal taxa. Thus, reduced plant diversity may constrain both fungal taxa richness and decomposition in fragmented coastal shrublands. Altogether, our findings provide evidence that even fungi may be affected by human-driven habitat fragmentation via direct effects of fragmentation on plants. Our findings underscore the importance

  16. Isotopic insights into microbial sulfur cycling in oil reservoirs

    Directory of Open Access Journals (Sweden)

    Christopher G Hubbard

    2014-09-01

    Full Text Available Microbial sulfate reduction in oil reservoirs (biosouring is often associated with secondary oil production where seawater containing high sulfate concentrations (~28 mM is injected into a reservoir to maintain pressure and displace oil. The sulfide generated from biosouring can cause corrosion of infrastructure, health exposure risks, and higher production costs. Isotope monitoring is a promising approach for understanding microbial sulfur cycling in reservoirs, enabling early detection of biosouring, and understanding the impact of souring. Microbial sulfate reduction is known to result in large shifts in the sulfur and oxygen isotope compositions of the residual sulfate, which can be distinguished from other processes that may be occurring in oil reservoirs, such as precipitation of sulfate and sulfide minerals. Key to the success of this method is using the appropriate isotopic fractionation factors for the conditions and processes being monitored. For a set of batch incubation experiments using a mixed microbial culture with crude oil as the electron donor, we measured a sulfur fractionation factor for sulfate reduction of -30‰. We have incorporated this result into a simplified 1D reservoir reactive transport model to highlight how isotopes can help discriminate between biotic and abiotic processes affecting sulfate and sulfide concentrations. Modeling results suggest that monitoring sulfate isotopes can provide an early indication of souring for reservoirs with reactive iron minerals that can remove the produced sulfide, especially when sulfate reduction occurs in the mixing zone between formation waters containing elevated concentrations of volatile fatty acids and injection water containing elevated sulfate. In addition, we examine the role of reservoir thermal, geochemical, hydrological, operational and microbiological conditions in determining microbial souring dynamics and hence the anticipated isotopic signatures.

  17. MICROBIAL SURFACTANTS IN ENVIRONMENTAL TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    T. P. Pirog

    2015-08-01

    Full Text Available It was shown literature and own experimental data concerning the use of microbial surface active glycolipids (rhamno-, sophoro- and trehalose lipids and lipopeptides for water and soil purification from oil and other hydrocarbons, removing toxic heavy metals (Cu2+, Cd2+, Ni2+, Pb2+, degradation of complex pollution (oil and other hydrocarbons with heavy metals, and the role of microbial surfactants in phytoremediation processes. The factors that limit the use of microbial surfactants in environmental technologies are discussed. Thus, at certain concentrations biosurfactant can exhibit antimicrobial properties and inhibit microorganisms destructing xenobiotics. Microbial biodegradability of surfactants may also reduce the effectiveness of bioremediation. Development of effective technologies using microbial surfactants should include the following steps: monitoring of contaminated sites to determine the nature of pollution and analysis of the autochthonous microbiota; determining the mode of surfactant introduction (exogenous addition of stimulation of surfactant synthesis by autochthonous microbiota; establishing an optimal concentration of surfactant to prevent exhibition of antimicrobial properties and rapid biodegradation; research both in laboratory and field conditions.

  18. Assessing functional equivalency of nekton habitat in enhanced habitats: Comparison of terraced and unterraced marsh ponds

    Science.gov (United States)

    La Peyre, M.K.; Gossman, B.; Nyman, J.A.

    2007-01-01

    A primary goal of many coastal restoration programs is to increase nekton habitat in terms of both quantity and quality. Using shallow water ponds rehabilitated with a technique called marsh terracing, we examined the quality of nekton habitat created, using and comparing several metrics including nekton density and diversity, functional group composition, and weight-length relationships as indirect measures of habitat quality. We examined three paired terraced and unterraced marsh ponds in southwest Louisiana. Nekton, submerged aquatic vegetation (SAV), and soil and water quality variables were sampled bimonthly from April 2004 through April 2005 at four subtidal habitat types: terraced nearshore, terraced open water, unterraced nearshore, and unterraced open water. Results indicate that terraced ponds had increased the habitat value of degrading unterraced ponds over open water areas for estuarine nekton; nekton density and richness were similar between terraced and unterraced nearshore habitat types, but greater at all nearshore as compared to open water sites. Analysis of the distribution of nekton functional groups and weight:length ratios indicates the terraced and unterraced pond habitats were not functioning similarly: distribution of nekton functional groups differed significantly between habitat types with greater percentages of benthic-oriented species at unterraced open water habitats and higher percentage of open water species in terraced ponds as compared to unterraced ponds, and two of the six numerically dominant fish species had greater weight-length relationships in unterraced ponds as compared to terraced ponds. This lack of functional equivalency may be attributed to environmental differences between terraced and unterraced ponds such as water depth or SAV biomass, or the relatively young age of the terraces studied, which may not have allowed for the development of some critical habitat variables, such as soil organic matter that was found to

  19. Synergistic effects of habitat preference and gregarious behaviour on habitat use in coral reef cardinalfish

    Science.gov (United States)

    Gardiner, N. M.; Jones, G. P.

    2010-12-01

    Spatial distributions of coral reef fish species are potentially determined by habitat preferences and behavioural interactions. However, the relative importance of these factors and whether or not behavioural interactions reinforce or disrupt habitat associations are poorly understood. This paper explores the degree to which habitat and social preferences explain the association that three common coral reef cardinalfish species ( Zoramia leptacanthus, Archamia zosterophora and Cheilodipterus quinquelineatus; family Apogonidae) have with coral substrata at Lizard Island, Great Barrier Reef. At diurnal resting sites, species were strongly associated with branching corals, with 80-90% of each species inhabiting one branching coral species, Porites cylindrica. Species were also highly gregarious, forming large con-specific and hetero-specific aggregations in coral heads, potentially reinforcing habitat associations. Three-way choice experiments were conducted to test fishes habitat preferences for living coral over dead substrata, for particular coral species, and the influence of gregarious behaviour on these habitat choices. The strength of habitat preferences differed among species, with Z. leptacanthus preferring live coral and P. cylindrica, A. zosterophora preferring P. cylindrica, whether live or dead and C. quinquelineatus exhibiting no preferences. All species were attracted to conspecifics, and for C. quinquelineatus and A. zosterophora, conspecific attraction resulted in stronger preferences for live corals. Gregarious behaviour also increased C. quinquelineatus associations with P. cylindrica. The relative strength of social attraction versus habitat preferences was investigated by comparing fish habitat preferences in the presence and/or absence of conspecifics. The presence of conspecifics on non-preferred rubble habitat reduced each species association with live coral. This study’s results indicate that in the field, habitat preferences and

  20. CADDIS Volume 2. Sources, Stressors and Responses: Physical Habitat - Simple Conceptual Diagram

    Science.gov (United States)

    Introduction to the Physical Habitat module, when to list Physical Habitat as a candidate cause, ways to measure Physical Habitat, simple and detailed conceptual diagrams for Physical Habitat, Physical Habitat module references and literature reviews.