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Verônica da Fonsêca-Genevois Paul J. Somerfield Maria Helena Baeta Neves Ricardo Coutinho Tom Moens 《Marine Biology》2006,148(5):1039-1050
An experiment was undertaken at Farol Island, Brazil, to examine colonization of bare aluminium surfaces by microbes and meiofauna.
It was hypothesized that a primary source of meiofaunal colonists was sediment resuspended during upwelling events, two of
which occurred during the experiment. Microbial biofilms formed on the experimental substrata within 1 day, and continued
to develop throughout the experimental period. Among meiofaunal groups copepods also appeared on the first day, and nematodes
on the second. Meiofaunal community structure developed in three main phases: an initial phase of 2 days, characterized by
low abundances of copepods; a second phase during the first upwelling period characterized by higher abundances of copepods
and also by turbellarians; and a third phase from day 13 onwards characterized by relatively stable abundances of a range
of taxa including copepods, cirripedes, nematodes and ostracods. Nematode assemblages also developed in three phases, but
with different timings coinciding with upwelling events: an initial phase, from the beginning of the experiment to day 9,
characterized by few species and low (or no) abundances; a second phase following the first upwelling characterized by moderate
abundances of Chromadorina, Chromadorella, Daptonema and Euchromadora sp. 3; a third phase following the second upwelling period (from day 26 onwards) in which Daptonema disappeared and the assemblage was characterized by moderate to high abundances of Euchromadora (species 1 and 2) and Chromadorella. Although shifts in nematode assemblage structure coincided with upwelling events no evidence was found for sediments being
the primary source of colonizers on the aluminium substrata, in contrast to our hypothesis. 相似文献
2.
P.J. Somerfield M. Atkins S.G. Bolam K.R. Clarke E. Garnacho H.L. Rees R. Smith R.M. Warwick 《Marine Biology》2006,148(6):1231-1240
Phylum-level meta-analysis was applied to 192 samples from a variety of dredgings disposal and relocation sites around the
coast of England and Wales. No consistent relationship was found between the disturbance status of macrobenthic communities
within disposal sites and the nature or amount of dredgings disposed. Differences between samples within and outside disposal
sites were generally smaller than differences between different sites and various patterns of impact were detected. It is
concluded that dredgings disposal has two contrasting impacts on benthic communities. One, associated with organic enrichment,
leads to communities dominated by annelids and nematodes. The other, associated with intense physical disturbance, favours
large motile or armoured forms, such as bivalve molluscs and crustaceans. These effects may act antagonistically, and in a
phylum-level meta-analysis may cancel each other out. None of the samples examined from offshore disposal sites was grossly
disturbed, in terms of the proportional contribution to production from different phyla, and overall most samples ranged from
moderately disturbed to undisturbed. The ecological impacts associated with the intertidal placement of material (beneficial
use schemes) were comparable to those observed for the conventional sea disposal sites. 相似文献
3.
S. T. Buckland S. R. Baillie J. McP. Dick D. A. Elston A. E. Magurran E. M. Scott R. I. Smith P. J. Somerfield A. C. Studeny A. Watt 《Environmental and Ecological Statistics》2012,19(4):601-626
We consider quantification of biodiversity in the context of targets set by the Convention on Biological Diversity. Implicit in such targets is a requirement to monitor biodiversity at a regional level. Few monitoring schemes are designed with these targets in mind. Monitored sites are typically not selected to be representative of a wider region, and measures of biodiversity are often biased by a failure to account for varying detectability among species and across time. Precision is often not adequately quantified. We review methods for quantifying the biodiversity of regions, consider issues that should be addressed in designing and evaluating a regional monitoring scheme, and offer a practical guide to what types of survey are appropriate for addressing different objectives for biodiversity monitoring. 相似文献
4.
Gritta Veit-Köhler Marleen De Troch Mateja Grego Tania Nara Bezerra Wendy Bonne Guy De Smet Christina Folkers Kai Horst George Chen Guotong Rudy Herman Rony Huys Nikolaos Lampadariou Jürgen Laudien Pedro Martínez Arbizu Armin Rose Michaela Schratzberger Sybille Seifried Paul Somerfield Jan Vanaverbeke Edward Vanden Berghe Magda Vincx Borut Vriser Leen Vandepitte 《Marine Biology》2010,157(8):1819-1835
A large-scale database concerning benthic copepods from the Arctic, Baltic Sea, North Sea, British Isles, Adriatic Sea and Crete was compiled to assess species richness, biodiversity, communities, ecological range size and biogeographical patterns. The Adriatic showed the highest evenness and the most species-rich communities. Assemblages from the North Sea, British Isles, Baltic and Crete had a lower evenness. The British Isles were characterised by impoverished communities. The ecological specificity of copepod species showed two diverging trends: higher specificity of species in more diverse assemblages was observed in the Adriatic, North Sea and Baltic. A uniformly high species specificity disregarding sample diversity was found on Crete and in the British Isles. Benthic copepod communities showed distinct patterns that clearly fit the predefined geographical regions. Communities were distinguishable and β-diversity was found to be high around Europe, indicating a high species turnover on the scale of this investigation. The British Isles and the North Sea were found to be faunistic links to the Baltic and the Arctic. 相似文献
5.
Most studies of spatial patterns of invertebrates in soft sediments have concentrated on populations of individual species.
Those that examined patterns in communities have tended to employ categorical analytical techniques. Using macrofaunal abundance
data from van Veen grab samples collected 20 to 100 m apart in known spatial arrangements from Scottish sea-lochs, the relationships
between patterns in macrobenthic species composition and distances between samples were explored using matrix correlations
in a non-parametric framework. Using a simple definition of spatial structure, i.e. that intersample distances are monotonically
correlated with intersample species-similarity, spatial structure at each of seven stations was assessed using non-parametric
Mantel tests based on rank-correlations. Changes in community structure were positively correlated with distance at all sites
in Loch Etive, on both current-swept muddy sands and soft deep muds. Different components of the macrobenthos contributed
to spatial pattern at each site. Simple spatial structure was also detectable at a muddy-sand site in Loch Creran, but neither
on soft mud, nor at the soft mud site in the Firth of Lorne. The concept of rank-correlograms was introduced. These were used
to examine the extent and form of spatial structure in different components of the macrobenthos at each site. Relationships
between similarity and distance were neither simple nor consistent. Results were compared to previous studies which used the
same data, and it was concluded that studies carried out at a particular scale, or on a particular component of the benthos,
are unlikely to be successful in predicting spatial relationships at other scales or for other components of the benthos.
Correlational rather than categorical analyses are recommended for exploratory studies of spatial relationships in the benthos.
Analyses of the spatial structure at these seven sea-loch sites suggests that by ensuring that samples are at least 40 m apart
an investigator is unlikely to underestimate variability or otherwise invalidate statistical analyses based on the use of
the samples as replicates. Spacing samples up to 100 m apart may increase variability estimates, further reducing the chance
of concluding that a difference exists when one does not.
Received: 4 May 1999 / Accepted: 8 March 2000 相似文献
6.
Lin DS Greenwood PF George S Somerfield PJ Tibbett M 《Environmental science and pollution research international》2011,18(7):1070-1078
Background, aim and scope
Soil organic matter (SOM) is known to increase with time as landscapes recover after a major disturbance; however, little is known about the evolution of the chemistry of SOM in reconstructed ecosystems. In this study, we assessed the development of SOM chemistry in a chronosequence (space for time substitution) of restored Jarrah forest sites in Western Australia. 相似文献7.
The application of an indicator based on taxonomic distinctness for UK marine biodiversity assessments 总被引:3,自引:0,他引:3
Leonard DR Robert Clarke K Somerfield PJ Warwick RM 《Journal of environmental management》2006,78(1):52-62
Mankind needs to use the resources and opportunities offered by the marine environment while protecting ecological processes and systems. This is the foundation for sustainable development, which can only be achieved by adopting an appropriate management approach. Whether internationally or at a regional scale, successful management of marine ecosystems needs to be based on a scientifically robust approach to monitoring environmental change. Within such a framework, the conservation of marine biological diversity is problematic, as many conventional measures of diversity are not appropriate for measuring the types of change that require management. New indicators are required and in this paper we summarise some of the current methodology being used to derive such indices, which may be used to evaluate the effectiveness of marine stewardship initiatives. Through a series of examples we demonstrate the application of the taxonomic distinctness indicator of biodiversity to marine environmental assessment and its development towards becoming an operational tool. 相似文献
8.
M. Schratzberger N. Lampadariou P. J. Somerfield L. Vandepitte E. Vanden Berghe 《Marine Biology》2009,156(4):709-724
Physical disturbance is a key factor in controlling the spatial and temporal composition of shallow-water benthic communities.
Like shallow waters, deeper waters are increasingly subject to a range of anthropogenic disturbances, which can lead to significant
alterations in sedimentation patterns. These alterations often exceed naturally occurring changes. We used a combined analysis
of six independent data sets arising from large-scale field surveys and small-scale laboratory experiments to investigate
the effects of seabed disturbance on nematode communities. Disturbance response was documented as a function of disturbance
type (coastal development, dredged material disposal, bottom trawling, glacial fjord) and intensity (low, medium, high). Natural
and man-induced seabed disturbance exerted differential effects on exposed populations, generating changes in the taxonomic
(genus) and functional (feeding type) attributes of their assemblages. The genus composition of nematode assemblages from
geographically separate seas converged with increased level of various types of man-made disturbance. Assemblages present
along a gradient of natural disturbance in a glacial fjord followed an opposite response vector, suggesting that community
changes induced by anthropogenic activities, or experimental treatments simulating the principal impacts of these, inherently
differ from disturbance of natural origin. Changes in trophic diversity and structure were primarily driven by factors confounded
with physical disturbance, such as metal contamination. Coupling the results of analyses at multiple scales proved a useful
means of providing deeper insights into the general response of ecological communities to environmental change. 相似文献
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