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11.
Jean-Pierre?Vanden?BosscheEmail author Philippe?Usseglio-Polatera 《Hydrobiologia》2005,551(1):253-271
The river types in Wallonia (Belgium) were defined according to the system B of the European Water Framework Directive (WFD)
taking into account obligatory and optional factors synthesized in three criteria: ‘size’, ‘slope’ and ‘natural region’. Under
the hypothesis that benthic invertebrate assemblages would be specialized according to river type, a set of 627 faunal samples
originating from an 11-year sampling period was tested to characterize river types with faunal assemblages.
A multivariate approach led to gather 23 river types into seven groups exhibiting similar faunal assemblages.
Using biocenotic metrics based on benthic invertebrate assemblages (e.g., the French standard IBGN), type-specific reference
conditions and ecological status class limits were defined for each ‘natural’ river type group. Ecological potential was defined
for heavily modified and for artificial (i.e., man-made canals) types.
An ‘ecological status’ evaluation strategy was therefore developed and applied in the southern – and more natural – part of
Wallonia, where many reference sites were available. In the northern part of Wallonia (i.e., the ‘Loess region’) where no
high quality site was available, the expert judgement took a larger part in the definition of the reference conditions and
of the ecological status class limits, in addition to the calculations. Two independent distribution gradients of taxa assemblages
resulted from multivariate ordination: a first ‘saprobity axis’, as the taxa-sensitivity to organic contamination was increasing
from ‘very resistant’ taxa (mainly located in the ‘Loess region’) to ‘sensitive’ and ‘very sensitive’ taxa (from the river
types belonging to the Condroz, the Famenne, the Arden and the Jurassic regions) and a second axis characterizing the Meuse-specific
faunal assemblage, gathering exotic species and typical limnophilous taxa of large heavily modified rivers. The ecological
status monitoring management system developed in this study – i.e., the definition of faunal river type groups, related reference
conditions and ecological status class limits – represents a proposal to be integrated in the ecological status assessment
of biological elements for the implementation of the WFD and was tested in Wallonia. For the period 2000–2002 involving 349
different sites, the element ‘benthic invertebrate fauna’ was in that way classified ‘high status’ for 31.5% of sites, ‘good
status’ for 31.5% and below ‘good status’ for 37% of sites. The best ecological status (i.e., 100% ‘high’ and ‘good’ status)
was found in river type ‘Arden’s xenotrophic brooks with strong slope’ and in river types 8large rivers with medium slope’.
The worst status was found in river types ‘Loess brooks and rivers with medium slope’. 相似文献
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Changes in functional biodiversity in an invaded freshwater ecosystem: the Moselle River 总被引:1,自引:1,他引:0
Simon?DevinEmail author Jean-Nicolas?Beisel Philippe?Usseglio-Polatera Jean-Claude?Moreteau 《Hydrobiologia》2005,542(1):113-120
The spread of non-indigenous species and the decline of autochthonous ones are leading to a homogenization of freshwater fauna
in terms of systematic units, but the functional consequences are poorly documented. We studied the peculiar case of the lower,
French section of the Moselle River where 20 invertebrate species have been introduced since 1854, with a rate increasing
exponentially with time. Dredge sampling performed in 1994, 1996, 2000 and 2001 at four sampling stations allowed for an evaluation
of faunal changes in terms of composition, structure and function. During this period, no structural changes were recorded
in spite of multiple, new and successful introductions. The evaluation of functional modifications was based on a typology
of taxa exhibiting homogeneous biological/ecological traits. Functional diversity, measured as the diversity of taxa distribution
among functional groupings, revealed a significant increase between 1994/1996 and 2000/2001 because those species that were
over-represented during the former period reached more equilibrated densities during the latter. The major, indirect implications
of these functional changes are discussed. 相似文献
15.
The STAR project: context, objectives and approaches 总被引:20,自引:20,他引:0
Mike Furse Daniel Hering Otto Moog Piet Verdonschot Richard K. Johnson Karel Brabec Kostas Gritzalis Andrea Buffagni Paulo Pinto Nikolai Friberg John Murray-Bligh Jiri Kokes Renate Alber Philippe Usseglio-Polatera Peter Haase Roger Sweeting Barbara Bis Krzysztof Szoszkiewicz Hanna Soszka Gunta Springe Ferdinand Sporka Il’ja Krno 《Hydrobiologia》2006,566(1):3-29
STAR is a European Commission Framework V project (EVK1-CT-2001-00089). The project aim is to provide practical advice and solutions with regard to many of the issues associated with the Water Framework Directive. This paper provides a context for the STAR research programme through a review of the requirements of the directive and the Common Implementation Strategy responsible for guiding its implementation. The scientific and strategic objectives of STAR are set out in the form of a series of research questions and the reader is referred to the papers in this volume that address those objectives, which include: (a) Which methods or biological quality elements are best able to indicate certain stressors? (b) Which method can be used on which scale? (c) Which method is suited for early and late warnings? (d) How are different assessment methods affected by errors and uncertainty? (e) How can data from different assessment methods be intercalibrated? (f) How can the cost-effectiveness of field and laboratory protocols be optimised? (g) How can boundaries of the five classes of Ecological Status be best set? (h) What contribution can STAR make to the development of European standards? The methodological approaches adopted to meet these objectives are described. These include the selection of the 22 stream-types and 263 sites sampled in 11 countries, the sampling protocols used to sample and survey phytobenthos, macrophytes, macroinvertebrates, fish and hydromorphology, the quality control and uncertainty analyses that were applied, including training, replicate sampling and audit of performance, the development of bespoke software and the project outputs. This paper provides the detailed background information to be referred to in conjunction with most of the other papers in this volume. These papers are divided into seven sections: (1) typology, (2) organism groups, (3) macrophytes and diatoms, (4) hydromorphology, (5) tools for assessing European streams with macroinvertebrates, (6) intercalibration and comparison and (7) errors and uncertainty. The principal findings of the papers in each section and their relevance to the Water Framework Directive are synthesised in short summary papers at the beginning of each section. Additional outputs, including all sampling and laboratory protocols and project deliverables, together with a range of freely downloadable software are available from the project website at www.eu_star.at. 相似文献