scholarly journals From Surface to Subsurface: Diversity, Composition, and Abundance of Sessile and Endolithic Bacterial, Archaeal, and Eukaryotic Communities in Sand, Clay and Rock Substrates in the Laurentians (Quebec, Canada)

2022 ◽  
Vol 10 (1) ◽  
pp. 129
Author(s):  
Julia Meyer ◽  
Sheri Zakhary ◽  
Marie Larocque ◽  
Cassandre S. Lazar
Keyword(s):  
Biotic Interactions ◽  
Vertical Movement ◽  
Shallow Subsurface ◽  
Aquifer Systems ◽  
Geological Formation ◽  
Systematic Understanding ◽  
Microbial Groups ◽  
Terrestrial Subsurface ◽  
Do So ◽  
Planktonic Communities

Microbial communities play an important role in shallow terrestrial subsurface ecosystems. Most studies of this habitat have focused on planktonic communities that are found in the groundwater of aquifer systems and only target specific microbial groups. Therefore, a systematic understanding of the processes that govern the assembly of endolithic and sessile communities is still missing. This study aims to understand the effect of depth and biotic factors on these communities, to better unravel their origins and to compare their composition with the communities detected in groundwater. To do so, we collected samples from two profiles (~0–50 m) in aquifer sites in the Laurentians (Quebec, Canada), performed DNA extractions and Illumina sequencing. The results suggest that changes in geological material characteristics with depth represent a strong ecological and phylogenetical filter for most archaeal and bacterial communities. Additionally, the vertical movement of water from the surface plays a major role in shallow subsurface microbial assembly processes. Furthermore, biotic interactions between bacteria and eukaryotes were mostly positive which may indicate cooperative or mutualistic potential associations, such as cross-feeding and/or syntrophic relationships in the terrestrial subsurface. Our results also point toward the importance of sampling both the geological formation and groundwater when it comes to studying its overall microbiology.

scholarly journals Case sophisticated aesthetic prosthetics

2016 ◽  
Vol 12 (1) ◽  
pp. 85-89
Author(s):  
Ф. Маннанова ◽  
F. Mannanova ◽  
Т. Ганеев ◽  
T. Ganeev ◽  
И. Исхаков ◽  
...  
Keyword(s):  
Tooth Extraction ◽  
Periodontal Diseases ◽  
Vertical Movement ◽  
Orthopedic Treatment ◽  
Partial Loss ◽  
Treatment Results ◽  
Pathological Conditions ◽  
Preparatory Phase ◽  
Do So ◽  
Partial Destruction

<p>The authors describe two clinical cases with sophisticated prosthetics defects dentition with allceramic. Of complications (increased abrasion, deformation of dentition, reduces occlusion) after tooth extraction complicated rational prosthesis. It took a phased prosthesis with a preparatory phase. Failure to do so can lead to complications and aesthetic dissatisfaction of patients from the orthopedic treatment results.</p><p>The deformations of dentition occur when the full or partial destruction of the crowns of teeth, dentition defect with partial loss, periodontal diseases, tumors and other pathological conditions that lead to a change in the position of teeth (sagittal, vertical and transversal) of the three mutually perpendicular planes.</p><p>The appearance of defects violates not only the morphological unity of the dentition, but also leads to its complex restructuring, first appearing near the defect, and then extended to the entire dentition and the entire dentition system. Outwardly, this restructuring is manifested teeth tilt toward the defect, the vertical movement of the teeth, deprived of antagonists, their inclination mainly in the lingual side, rotating around an axis.</p><p>Shifting teeth leads eventually to a more or less pronounced disturbance of the occlusal surface of the dentition, lower occlusal height complicating clinic partial loss of teeth, making it difficult to conduct a rational choice and orthopedic treatment.</p>

Actinide Colloids in Natural Aquifer Systems

MRS Bulletin ◽  
1994 ◽  
Vol 19 (12) ◽  
pp. 47-53 ◽  
Author(s):  
J.I. Kim
Keyword(s):  
Mobile Species ◽  
Aquifer Systems ◽  
Equilibrium Reactions ◽  
Geological Formation ◽  
Geochemical Reactions ◽  
Chemical States ◽  
Technological Challenge ◽  
General Goals ◽  
Colloidal Species ◽  
Low Solubility

Immobilization and geological isolation are the general goals of nuclear waste disposal. The appropriate isolation of immobilized long-lived radionuclides, mostly actinide elements, from interaction with water for a period of many thousands of years in any given geological formation is a scientific and technological challenge. This challenge can be met by considering a multibarrier concept that appraises engineered, geoengineered, and geological barriers designed to confine the migration of long-lived actinides. Once interaction with water occurs, one may expect many complex geochemical reactions of immobilized actinides; actinides will therefore be distributed into two kinds of chemical states, mobile and immobile species. Reflecting results in laboratory systems, the two species are expected to be chemical partners in equilibrium reactions. In multicomponent geochemical systems, however, the chemistry of the mobile and immobile species of actinides in trace concentration is, in general, masked by geochemical reactions of natural aquatic constituents, which are found in much higher concentrations. The mobile species are either complexed anions or colloidal species, whereas the immobile species are new solid phases of very low solubility, which are thermodynamically better stabilized than in the original host phases.

Indirect biotic interactions of plant invasions with native plants and animals.

2020 ◽  
pp. 308-323
Author(s):  
Warwick J. Allen ◽  
Keyword(s):  
Invasive Plants ◽  
Biotic Interactions ◽  
Direct Interaction ◽  
Invasion Biology ◽  
Plant Invasions ◽  
Ecological Processes ◽  
Research Areas ◽  
Systematic Understanding ◽  
Indirect Impacts ◽  
Indirect Facilitation

Invasive plants often occur at high densities and tend to be highly generalist in their interactions with herbivores, pathogens, mycorrhiza, endophytes and pollinators. These characteristics mean that invasive plants should frequently participate in diverse indirect biotic interactions with the surrounding community, mediated by their direct interaction partners (e.g. antagonists and mutualists). Indirect interactions play an important role in many ecological processes, yet we still lack a systematic understanding of the circumstances under which they influence the success and impacts of invasive species. In this chapter, I first describe several of the indirect interaction pathways that are commonly encountered in invasion biology and review their contribution to the impacts of plant invasions on co-occurring species. The literature review revealed that there are now many case studies describing various indirect impacts of invasive plants. However, identical interaction motifs (e.g. plant-enemy-plant, plant-mutualist-plant) can bring about several possible outcomes, depending upon each species' provenance, relative abundances and interaction strengths, abiotic resource availability, spatial and temporal scale and the influence of other species. Moreover, knowledge gaps identified include a lack of studies of indirect facilitation outside of plant-pollinator systems, limited consideration of indirect invader impacts on other non-native species, and the scarcity of generalizable results to date. Second, I integrate the literature with some trending research areas in invasion biology (interaction networks, biogeography, invasion dynamics) and identify some potential future research directions. Finally, I discuss how knowledge about indirect biotic interactions could be incorporated into the management of invasive plants.

Indirect biotic interactions of plant invasions with native plants and animals.

2020 ◽  
pp. 308-323
Author(s):  
Warwick J. Allen
Keyword(s):  
Invasive Plants ◽  
Biotic Interactions ◽  
Direct Interaction ◽  
Invasion Biology ◽  
Plant Invasions ◽  
Ecological Processes ◽  
Research Areas ◽  
Systematic Understanding ◽  
Indirect Impacts ◽  
Indirect Facilitation

Abstract Invasive plants often occur at high densities and tend to be highly generalist in their interactions with herbivores, pathogens, mycorrhiza, endophytes and pollinators. These characteristics mean that invasive plants should frequently participate in diverse indirect biotic interactions with the surrounding community, mediated by their direct interaction partners (e.g. antagonists and mutualists). Indirect interactions play an important role in many ecological processes, yet we still lack a systematic understanding of the circumstances under which they influence the success and impacts of invasive species. In this chapter, I first describe several of the indirect interaction pathways that are commonly encountered in invasion biology and review their contribution to the impacts of plant invasions on co-occurring species. The literature review revealed that there are now many case studies describing various indirect impacts of invasive plants. However, identical interaction motifs (e.g. plant-enemy-plant, plant-mutualist-plant) can bring about several possible outcomes, depending upon each species' provenance, relative abundances and interaction strengths, abiotic resource availability, spatial and temporal scale and the influence of other species. Moreover, knowledge gaps identified include a lack of studies of indirect facilitation outside of plant-pollinator systems, limited consideration of indirect invader impacts on other non-native species, and the scarcity of generalizable results to date. Second, I integrate the literature with some trending research areas in invasion biology (interaction networks, biogeography, invasion dynamics) and identify some potential future research directions. Finally, I discuss how knowledge about indirect biotic interactions could be incorporated into the management of invasive plants.

Microbial population responses in three stratified Antarctic meltwater ponds during the autumn freeze

2012 ◽  
Vol 24 (6) ◽  
pp. 571-588 ◽  
Author(s):  
Karl Safi ◽  
Ian Hawes ◽  
Brian Sorrell
Keyword(s):  
Microbial Communities ◽  
Microbial Population ◽  
Grazing Pressure ◽  
Filamentous Cyanobacteria ◽  
Ice Shelf ◽  
Population Responses ◽  
Upper Mixed Layer ◽  
Microbial Groups ◽  
Planktonic Communities

AbstractThe planktonic microbial communities of three meltwater ponds, located on the McMurdo Ice Shelf, were investigated from the end of January 2008 to early April, during which almost the entire pond volumes froze. The ponds were comprised of an upper mixed layer overlying a salt-stabilized density gradient in which planktonic communities were primarily embedded. Plankton comprised all components of the “microbial loop”, though carnivorous protists were rare. As the ponds froze and light became increasingly limited, it was expected conditions would induce physiological changes altering the functional role of autotrophic and heterotrophic microplankton within the ponds. The results showed that microbial groups responded to the onset of winter by declining in abundance, though an exception was the appearance of filamentous cyanobacteria in the water column in March. As freezing progressed, autotrophs declined more rapidly than heterotrophs and grazing rates and abundances of mixotrophic and heterotrophic organisms increased. Grazing pressure on bacteria and picophytoplankton also increased, in part explaining their decline over time. The results indicate that stressors imposed during freezing select for increasing heterotrophy within the remaining microbial communities, although all components of the food web eventually decline as the final freeze approaches.

scholarly journals GIS: A USEFUL TOOL FOR MANAGING OF TRANSBOUNDARY AQUIFERS: A CASE STUDY FROM PRESPA LAKE BASIN

2017 ◽  
Vol 50 (2) ◽  
pp. 750
Author(s):  
E. Kiri
Keyword(s):  
Geographical Information Systems ◽  
Geographical Information ◽  
Lake Basin ◽  
International Borders ◽  
Aquifer Systems ◽  
Geological Formation ◽  
Gis Environment ◽  
Transboundary Aquifers ◽  
Prespa Lake

Prespa Lake Basin is a transboundary basin that’s shared between Albania-Greece-FYROM. This region has a very complicated geology. The main aquifer systems are developed in carbonate rocks (karst aquifers) crossing international borders (transboundary aquifers). A map was constructed in GIS environment clearly display that each geologic age has one index, in one polygon, with the respective geological formation. The map was first digitalized with an AutoCAD program and then all the layers were exported in the program mentioned above. Not only does this map represent the hydrogeological features of the area but it also serves as a database of general characteristics, such as, the rock type, the infiltration coefficient, the yield of wells and springs, groundwater resource and permeability can be found on this base. Furthermore, chemical data can be added to the map, supplying more information on the surface and groundwater. Geographical Information Systems (GIS) is a useful tool for water resources management in the frame of international cooperation and coordination.

scholarly journals Airborne geophysical surveys of the lower Mississippi Valley demonstrate system-scale mapping of subsurface architecture

2021 ◽  
Vol 2 (1) ◽  
Author(s):  
Burke J. Minsley ◽  
J. R. Rigby ◽  
Stephanie R. James ◽  
Bethany L. Burton ◽  
Katherine J. Knierim ◽  
...  
Keyword(s):  
Groundwater Age ◽  
Regional Scale ◽  
The United States ◽  
Shallow Aquifer ◽  
Mississippi Valley ◽  
Seismic Zone ◽  
Lower Mississippi Valley ◽  
Shallow Subsurface ◽  
Aquifer Systems ◽  
Geophysical Surveys

AbstractThe Mississippi Alluvial Plain hosts one of the most prolific shallow aquifer systems in the United States but is experiencing chronic groundwater decline. The Reelfoot rift and New Madrid seismic zone underlie the region and represent an important and poorly understood seismic hazard. Despite its societal and economic importance, the shallow subsurface architecture has not been mapped with the spatial resolution needed for effective management. Here, we present airborne electromagnetic, magnetic, and radiometric observations, measured over more than 43,000 flight-line-kilometers, which collectively provide a system-scale snapshot of the entire region. We develop detailed maps of aquifer connectivity and shallow geologic structure, infer relationships between structure and groundwater age, and identify previously unseen paleochannels and shallow fault structures. This dataset demonstrates how regional-scale airborne geophysics can close a scale gap in Earth observation by providing observational data at suitable scales and resolutions to improve our understanding of subsurface structures.

scholarly journals Soil depth matters: Shift in composition and inter-kingdom co-occurrence patterns of microorganisms in forest soils

2021 ◽  
Author(s):  
Sunil Mundra ◽  
O Janne Kjønaas ◽  
Luis N Morgado ◽  
Anders Kristian Krabberød ◽  
Yngvild Ransedokken ◽  
...  
Keyword(s):  
Soil Depth ◽  
Mineral Soil ◽  
Soil Microbial Communities ◽  
Biotic Interactions ◽  
Sharp Decrease ◽  
Organic Layer ◽  
Mineral Layer ◽  
Network Analyses ◽  
Microbial Groups ◽  
Occurrence Patterns

Abstract Soil depth represents a strong physiochemical gradient that greatly affects soil-dwelling microorganisms. Fungal communities are typically structured by soil depth, but how other microorganisms are structured is less known. Here, we tested whether depth-dependent variation in soil chemistry affects the distribution and co-occurrence patterns of soil microbial communities. This was investigated by DNA metabarcoding in conjunction with network analyses of bacteria, fungi, as well as other micro-eukaryotes, sampled in four different soil depths in Norwegian birch forests. Strong compositional turnover in microbial assemblages with soil depth was detected for all organismal groups. Significantly greater microbial diversity and fungal biomass appeared in the nutrient-rich organic layer, with sharp decrease towards the less nutrient-rich mineral zones. The proportions of copiotrophic bacteria, Arthropoda and Apicomplexa were markedly higher in the organic layer, while patterns were opposite for oligotrophic bacteria, Cercozoa, Ascomycota and ectomycorrhizal fungi. Network analyses indicated more intensive inter-kingdom co-occurrence patterns in the upper mineral layer (0-5 cm) compared to the above organic and the lower mineral soil, signifying substantial influence of soil depth on biotic interactions. This study supports the view that different microbial groups are adapted to different forest soil strata, with varying level of interactions along the depth gradient.

Holding replication studies to mainstream standards of evidence

2018 ◽  
Vol 41 ◽  
Author(s):  
Duane T. Wegener ◽  
Leandre R. Fabrigar
Keyword(s):  
Replication Studies ◽  
Replication Research ◽  
Standards Of Evidence ◽  
Do So

AbstractReplications can make theoretical contributions, but are unlikely to do so if their findings are open to multiple interpretations (especially violations of psychometric invariance). Thus, just as studies demonstrating novel effects are often expected to empirically evaluate competing explanations, replications should be held to similar standards. Unfortunately, this is rarely done, thereby undermining the value of replication research.

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