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Community Data (community + data)

Distribution by Scientific Domains

Life Sciences	38%
Earth and Environmental Science	30%
Medical Sciences	23%

Kinds of Community Data

fish community data

Selected Abstracts

Restoration effort, habitat mosaics, and macroinvertebrates , does channel form determine community composition?

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2009
Sonja C. Jähnig
Abstract 1.In certain lower mountainous regions of Germany multiple-channel streams constitute the reference condition for stream restoration and conservation efforts. An increasing number of restoration projects re-establish such stream sections, but their impact on macroinvertebrate communities remains vague and needs further elaboration. 2.Seven pairs of single- and multiple-channel sections of mountain rivers were compared in terms of hydromorphology and macroinvertebrate communities. The stream sections were characterized by 16 hydromorphological metrics at various scales, e.g. shore length, channel feature or substrate diversity, flow variability and substrate coverage. Macroinvertebrate data were obtained from 140 substrate-specific samples, which were combined to form representative communities for each section. Community data were subject to similarity and cluster analyses. Thirty-five metrics were calculated with the taxa lists, including number of taxa, abundance, feeding type, habitat and current preferences. 3.Bray,Curtis similarity was very high (69,77%) between communities of single- and multiple-channel sections. Biological metrics were correlated with hydromorphological parameters. Mean Spearman rank r was 0.59 (absolute values). The biological metrics percentage of the community preferring submerged vegetation, being grazers and scrapers or active filter feeders, percentage of epipotamal preference and the percentage of current preference (rheo- to limnophil and rheobiont) were significantly correlated with hydromorphological parameters. 4.Differences between stream sections can be attributed to single taxa occurring only in either the single- or multiple-channel sections. These exclusive taxa were mainly found on organic substrates such as living parts of terrestrial plants, large wood, coarse particulate organic matter (CPOM) and mud. Reasons for high similarity of macroinvertebrate communities from single- or multiple-channel sections are discussed, including the influence of large-scale catchment pressures, length of restored sections and lack of potential re-colonizers. Copyright © 2008 John Wiley & Sons, Ltd. [source]

The oral health status of patients on oral bisphosphonates for osteoporosis

AUSTRALIAN DENTAL JOURNAL, Issue 4 2008
R Kunchur
Abstract Background:, The oral health status of patients on bisphosphonates is the key to the patient's ongoing health and well-being. If they are orally healthy, invasive bone procedures, particularly extractions can be avoided, then the risk of osteonecrosis of the jaws (ONJ) is low. Methods:, The records of 49 consecutive patients on oral bisphosphonates, referred to the Oral and Maxillofacial Surgery Unit (OMSU) for an oral health check and probable extractions, were retrospectively reviewed. The DMFT, periodontal and pathologic state were calculated from the OPG radiographs. An age and gender matched control group, from patients referred to the OMSU but who were not on oral bisphosphonates, were similarly assessed. Community data were also obtained. Results:, The DMFT score for the oral bisphosphonate group was 29: Decayed 3, Missing 10, Filled 16. The control group DMFT score was 24: Decayed 5, Missing 11, Filled 8. Both groups had advanced periodontal disease (over 95 per cent) and were medically compromised (over 90 per cent). The DMFT for general community data for age matched government pensioners was 19.1: Decayed 0.8, Missing 10.4, Filled 7.9. With severe periodontal disease 23 per cent. Thus, the oral health of the oral bisphosphonate group was similar to the control group and both had more decayed teeth and periodontal disease than community values. Conclusions:, This study confirms that one cannot assume that a patient on an oral bisphosphonate for osteoporosis has a healthy mouth. It supports the view that all patients on bisphosphonates need to be seen by a dentist either before or soon after commencement of bisphosphonate therapy. [source]

Relating streamflow characteristics to specialized insectivores in the Tennessee River Valley: a regional approach,

ECOHYDROLOGY, Issue 4 2008
Rodney R. Knight
Abstract Analysis of hydrologic time series and fish community data across the Tennessee River Valley identified three hydrologic metrics essential to habitat suitability and food availability for insectivorous fish communities in streams of the Tennessee River Valley: constancy (flow stability or temporal invariance), frequency of moderate flooding (frequency of habitat disturbance), and rate of streamflow recession. Initial datasets included 1100 fish community sites and 300 streamgages. Reduction of these datasets to sites with coexisting data yielded 33 sites with streamflow and fish community data for analysis. Identification of critical hydrologic metrics was completed using a multivariate correlation procedure that maximizes the rank correlation between the hydrologic metrics and fish community resemblance matrices. Quantile regression was used to define thresholds of potential ranges of insectivore scores for given values of the hydrologic metrics. Increased values of constancy and insectivore scores were positively correlated. Constancy of streamflow maintains wetted perimeter, which is important for providing habitat for fish spawning and increased surface area for invertebrate colonization and reproduction. Site scores for insectivorous fish increased as the frequency of moderate flooding (3 times the median annual streamflow) decreased, suggesting that insectivorous fish communities respond positively to less frequent disturbance and a more stable habitat. Increased streamflow recession rates were associated with decreased insectivore scores. Increased streamflow recession can strand fish in pools and other areas that are disconnected from flowing water and remove invertebrates as food sources that were suspended during high-streamflow events. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Health-related quality of life in patients with Primary Sjögren's Syndrome and Xerostomia: a comparative study

GERODONTOLOGY, Issue 1 2002
Jocelyne Rostron
Abstract Objective: To compare the health status of groups of Primary Sjögren's and Xerostomia patients, using the Medical Outcomes Short Form 36 (SF-36). The SF-36 is a generic measure, divided into eight domains, used in the assessment of health-related quality of life. Patients and methods: The SF-36 was given to 2 groups: Group 1 comprised 43 patients diagnosed with Primary Sjögren's Syndrome (1SS) and an unstimulated whole salivary flow rate (UFR) of <0.1 ml/min). Group 2 (n = 40) reported Xerosiomia but had an UFR >0.2 ml/min. Sub groups of patients in Groups 1 and 2 were compared with community normative data, for the SF-36 Results: There were trends to suggest lower SF36 scores for 1SS patients but there were no significant differences between the mean domain scores of Groups 1 and 2. 1SS and Xerostomia patients registered lower mean scores across all 8 domains, compared with normative community data. Conclusion: The SF-36 was unable to detect significant differences between subjects with 1SS and Xerostomia but a larger sample size is required to confirm these findings. The results of this limited study suggest that a disease-specific measure is required to assess the impact 1SS on health-related Quality of life (QOL). [source]

Understanding the biodiversity consequences of habitat change: the value of secondary and plantation forests for neotropical dung beetles

JOURNAL OF APPLIED ECOLOGY, Issue 3 2008
Toby A. Gardner
Summary 1Secondary and plantation forests are becoming increasingly widespread in the tropics. A recent meta-analysis on the impacts of land-use change on tropical forest dung beetles concluded that regenerating forests can be effective in helping to offset species loss following deforestation. However, our understanding of the extent to which these results can be generalized to new locations remains very poor. 2We attempted to overcome many of the design limitations that characterize previous studies by collecting spatially independent dung beetle samples from primary, secondary and Eucalyptus plantation forests in north-east Brazilian Amazonia across a large quasi-experimental landscape that minimized confounding edge and fragmentation effects. 3We recorded 9203 dung beetles, comprising 85 species. Species richness was significantly higher in primary forest and the majority of species were more abundant there than elsewhere, whereas secondary and plantation sites harboured an impoverished subset of primary forest species. 4Our data illustrate the low value of tropical secondary and plantation forests for dung beetles in our study area, and our conclusions are more pessimistic than those of earlier studies. 5Because of differences in the order of species rank-abundance and rank-biomass patterns, re-coding community data from abundance to biomass significantly altered the analytical weight of individual species in determining community patterns. Larger bodied beetles were more prone to local extinctions and abundance declines and this effect was consistent both within and between genera. 6Synthesis and applications. Our study demonstrates that secondary and plantation forests in a large neotropical landscape host exceptionally impoverished dung beetle communities. Furthermore, the depletion of beetle abundance combined with a reduction in average body mass in converted forests is likely to have detrimental consequences for the maintenance of dung beetle-mediated ecosystem services in these habitats. Differences in biogeographical and landscape context, and the influence of common limitations in sampling design, may explain why many other studies have painted a more optimistic picture of the conservation value of anthropogenic habitats. In the absence of further evidence we caution strongly against the claim that forest regeneration schemes on degraded land can effectively offset the loss of species following deforestation, and urge that conservation strategies prioritize the protection of remaining areas of primary forest. [source]

The tripartite biogeographical index: a new tool for quantifying spatio-temporal differences in distribution patterns

JOURNAL OF BIOGEOGRAPHY, Issue 4 2006
Tom Schils
Abstract Aims, First, to develop an index that quantifies biogeographical patterns based on the basic descriptors of presence/absence distribution patterns (F, frequency; C, connectivity; G, grouping). Second, to test the proposed biogeographical index on a data set of macrophyte communities in the Arabian Sea using distribution data of macro-algae and seagrasses throughout the Indian Ocean. Location, Arabian Sea (regional macrophyte community data) and the larger Indian Ocean (oceanic distribution data). Methods, The proposed index is derived from the Tulloss tripartite similarity index. The tripartite biogeographical index (TBI = ,F × C × G) is calculated for a specific taxon and incorporates several fundamental parameters of presence/absence data in grid cell (block) patterns. TBI accounts for the relative abundance of a taxon, the average grouping of its occurrences, the average of minimal absence intervals between taxon presences and the largest coherent cluster of taxon occurrences, and also incorporates dispersal aspects. The macrophytes from the case study are among the best documented marine organisms in the Indian Ocean. The regional distribution data from the Arabian Sea result from exhaustive species lists from Masirah Island (Oman) and the Socotra Archipelago (Yemen). Results, TBI values fit a linear scale corresponding to the proportional presence and the distributional spread of taxa within a given geographical area. The three functions that constitute TBI can be evaluated separately or in association with TBI, to give detailed information on the important factors that characterize the biogeographical distribution of a taxon (or larger entities consisting of multiple taxa such as communities). The case study on Arabian macrophytes clarifies the use and explanatory power of the index. Main conclusions, The biogeographical descriptors can be combined into an index which accurately quantifies taxon occurrences and distribution types on a single linear scale from rare/scattered to abundant/grouped. Together with its three functions, the index allows for a non-arbitrary selection of taxa and taxon groupings based on their distribution pattern. The analysis of TBI values for the Arabian macrophyte communities confirms previous biogeographical findings and enables more detailed statistical analyses of the distribution data. [source]

Mesoscale distribution patterns of Amazonian understorey herbs in relation to topography, soil and watersheds

JOURNAL OF ECOLOGY, Issue 5 2005
FLÁVIA R. C. COSTA
Summary 1Many authors have suggested that topography and soils are the major determinants of species distributions and community patterns at small or regional scales, but few studies addressed the patterns at mesoscales. We used Reserva Ducke (100 km2) as a model to analyse the effects of soil, topography and watersheds on the variation of the herb community composition, and to determine the relative importance of the environmental factors on species composition. 2Taxonomic groups are frequently used as surrogates in studies of biodiversity distribution and complementarity, but their efficacy is controversial. We therefore studied the correlations between the distributional patterns of three different herb groups (Marantaceae, pteridophytes and ,others') and their responses to environmental predictors. 3Terrestrial herbs were sampled in 59 plots of 250 × 2 m, systematically distributed over the reserve. Plots followed isoclines of altitude, to minimize the internal variation of soil. Composition of the total herb community and of the three herb groups was summarized with PCoA. 4Soil structure, represented by PCA axes, was the main determinant of the variation in herb composition for all groups, but slope affected only pteridophytes. Soil and topography explained less than one-third of the variance in community data. Herb composition was significantly different between watersheds, but watersheds differ only slightly in soil parameters. Our results indicate high turnover in species composition, on spatial scales of 5,10 km in central Amazonia, which is not necessarily associated with soil change. 5Compositional patterns of the three groups analysed were significantly correlated, but with low values for the correlation coefficient. Although composition was correlated, the responses to environmental predictors differed among groups, and the use of one group as a surrogate will miss around 50% of the variation in other groups. 6Although important, soil and topography alone cannot predict herb community structure. Knowledge of geographical, historical or other landscape features, such as watershed morphology, may therefore be necessary to predict the turnover patterns over mesoscales. Moreover, the same factors may not have the same effectiveness as predictors of the structure of seemingly similar biological groups. [source]

Reconstructing riverine mesohabitat unit composition using fish community data and an autecology matrix

JOURNAL OF FISH BIOLOGY, Issue 4 2010
J. P. Suen
This research proposes a simplified method for estimating the mesohabitat composition that would favour members of a given set of aquatic species. The simulated composition of four types of mesohabitat units (deep pool, shallow pool, deep riffle and shallow riffle) could guide the design of in-stream structures in creating pool-riffle systems with ecological reference. Fish community data and an autecology matrix are used to support the development of a stream mesohabitat simulation based on regression models for reaches in mid to upper-order streams. The fish community-mesohabitat model results constitute a reference condition that can be used to guide stream restoration and ecological engineering decisions aimed at maintaining the natural ecological integrity and diversity of rivers. [source]

Temporal dynamics of marginal steppic vegetation over a 26-year period of substantial environmental change

JOURNAL OF VEGETATION SCIENCE, Issue 2 2009
Silvia Matesanz
Abstract Questions: (1) Is climate a strong driver of vegetation dynamics, including interannual variation, in a range margin steppic community? (2) Are there long-term trends in cover and species richness in this community, and are these consistent across species groups and species within groups? (3) Can long-term trends in plant community data be related to variation in local climate over the last three decades? Location: A range margin steppic grassland community in central Germany. Methods: Cover, number and size of all individuals of all plant species present in three permanent 1-m2 plots were recorded in spring for 26 years (1980,2005). Climatic data for the study area were used to determine the best climatic predictor for each plant community, functional group and species variable (annual data and interannual variation) using best subsets regression. Results: April and autumn temperature showed the highest correlation with total cover and species richness and with interannual variations of cover and richness. However, key climate drivers differed between the five most abundant species. Similarly, total cover and number and cover of perennials significantly decreased over time, while no trend was found for the cover and number of annuals. However, within functional groups there were also contrasting species-specific responses. Long-term temperature increases and high interannual variability in both temperature and precipitation were strongly related to long-term trends and interannual variations in plant community data. Conclusions: Temporal trends in vegetation were strongly associated with temporal trends in climate at the study site, with key roles for autumn and spring temperature and precipitation. Dynamics of functional groups and species within groups and their relationships to changes in temperature and precipitation reveal complex long-term and interannual patterns that cannot be inferred from short-term studies with only one or a few individual species. Our results also highlight that responses detected at the functional group level may mask contrasting responses within functional groups. We discuss the implications of these findings for attempts to predict the future response of biodiversity to climate change. [source]

Mixed stream channel morphologies: implications for fish community diversity

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 2 2009
Christina M. Cianfrani
Abstract 1.Stream classification systems are widely used in stream management and restoration. Whereas the principal morphological types of these classification systems are increasingly recognized for their ecological connections, the roles of intermediate and mixed morphologies are still poorly understood, yet may be biologically significant. 2.Twenty-five stream reaches in north-western Vermont were classified by channel morphology to determine whether fish community diversity differed among pool-riffle, mixed (i.e. pool-riffle/cascade, pool-riffle/other) and forced pool-riffle stream morphological groups. Stream reach surveys included cross-sectional surveys, longitudinal profiles, bed substrate characterization, and fish surveys. 3.Three fish community diversity measures were calculated: (1) species richness (S); (2) Shannon,Weaver Index (H,); and (3) Simpson's Index (1/D). Multivariate analysis of covariance (MANCOVA) followed by analysis of variance (ANOVA) were used to explore potential differences in fish diversity among stream morphological groups. Fish diversity was significantly different for all three community diversity measures (P,0.05), with pool-riffle/cascade morphology consistently exhibiting the greatest fish diversity and forced pool-riffle the lowest. 4.These results suggest that fish community diversity is significantly associated with distinct channel morphologies. Generally, pool-riffle/cascade and pool-riffle/other stream morphological groups supported habitats that fostered greater species diversity than more homogeneous and uniform pool-riffle reaches. The observed patterns of diversity are likely to be the result of habitat patches created by variations in flow and other physical characteristics in reaches of mixed morphologies. 5.These results support fish sampling schemes that incorporate morphological heterogeneity, such as proportional-distance designation. Sampling strategies that focus on homogeneous reaches may underestimate diversity, and misrepresent stream condition when fish community data are used in indices of biological integrity (IBIs). Reaches of mixed stream morphologies should be recognized as areas of biological importance in stream and catchment management and in conservation efforts. Copyright © 2008 John Wiley & Sons, Ltd. [source]

Lake habitat suitability for the rare European macrophyte Najas flexilis (Willd.) Rostk.

AQUATIC CONSERVATION: MARINE AND FRESHWATER ECOSYSTEMS, Issue 3 2005
& Schmidt
Abstract 1.Najas flexilis (Willd.) Rostk. & Schmidt is a submerged annual macrophyte, rare in Europe, which is protected under the EC Habitats Directive. 2.N. flexilis grows in deep, often coloured or turbid water in mesotrophic lakes. Because of this habitat preference it is difficult to locate and assess the ecological state of populations of the species for conservation monitoring purposes. 3.A method is described based on plant community information that can be used to determine the baseline probability that conditions in a lake are suitable for supporting N. flexilis growth. This can be applied to conservation management decisions, such as whether a detailed underwater survey is justified for monitoring the integrity of existing populations of N. flexilis, or whether the lake may be a suitable site for introduction, or reintroduction, of populations of the plant. 4.Two methods of plant community description are compared: a quantitative micro-habitat scale approach and a whole-lake-scale qualitative approach. Plant community data collected using each method were grouped using TWINSPAN, and environmental descriptors of the sites comprising each plant community group were compared statistically. 5.Micro-habitat-scale community groups differed significantly only in the light extinction coefficient, indicating the zone within the lake in which N. flexilis occurred. 6.The whole-lake-scale community groups differed in a number of environmental variables indicative of eutrophication and acidification, two major environmental threats to N. flexilis survival. 7.This study suggests that a lake-scale qualitative plant community description would be a better indicator of site suitability for N. flexilis growth than a quantitative micro-habitat plant community description. This is because the whole-lake-scale approach could detect a difference in the environmental factors that affect N. flexilis growth, which the micro-habitat scale approach could not. Copyright © 2005 John Wiley & Sons, Ltd. [source]