One of the challenges for large-scale, long-term ecological assessments lies in the integration of faunal datasets. A comparison was made between various ways of analysing benthic macrofaunal datasets using both taxon names as well as functional traits. The sampling stations were located on both sides of the average location of the Polar Front in the Barents Sea, and included the Spitsbergen Bank, slope areas and the deeper basins Storfjord Trough and Hopen Trough. Taxon richness and overall faunal biomass were highest at the shallowest stations, and lowest in the depressions and ice-influenced areas. The overall functioning of the faunal communities reflected the habitat type. In the trough areas, the sediment mixing depth was greatest, reflecting the bioturbatory activities of the fauna. The shallow, gravelly, erosion areas on the Spitsbergen Bank supported mostly surface-active taxa, consistent with the relatively low biological mixing depths. The mixed sediments of the slope environments supported a mixture of surface-active and bioturbating taxa. Functional trait coding offers an additional tool for mesoscale characterisation of communities, particularly for large-scale or long-term datasets, where taxonomic identifications may not be compatible. The results are discussed in terms of future research needs, in light of changing ecological conditions in the Barents Sea, as well as the need for refining environmental assessment tools.

Benthic fauna of the deeper waters (50–320 m) of the Franz Josef Land archipelago sampled in August 1992 using standard western techniques is described and compared with earlier Russian studies of the archipelago. Three faunal assemblages are recognised at depth ranges between 50–150, 150–300, and >300 m depth. Their distributions are related to depth and to different water masses derived from a mixture of Barents Sea water entering from the south at intermediate depths (20–150 m), and Atlantic water from the north below 300 m. The recorded faunal diversity and biomass is as high as or higher than that from comparable Arctic and northern boreal areas. Comparisons are also made with a complimentary Russian survey in the same area using different techniques. The Russian work collected larger organisms most effectively, whereas the present work recorded the smaller taxa more efficiently. Russian surveys provide complementary data to western studies, but care must be taken when comparing studies as they reflect biases in sampling gear and scientific emphasis. These data intercalibrations are important as Russian archives contain a wealth of information that, if used correctly in association with western data sources, will be useful in environmental monitoring studies as human activities increase in the Eurasian Arctic.

By comparing benthic foraminiferal and macrofaunal responses to sewage sludge disposal in the Firth of Clyde (Scotland), we wanted to investigate the possibility of using foraminifera as bio-indicators of marine environmental degradation. Both groups present a similar distributional pattern, with poor faunas composed of species tolerant to strong oxygen depletion near to the disposal site, surrounded by high density of opportunistic species. Farther away, faunal density decreases and equilibrium taxa gradually replace opportunistic species. No more environmental impact is perceptible beyond 3 km. Nevertheless, some differences exist: foraminifera appear to be more impacted at the disposal site, probably as a consequence of the low pH, a supplementary stress factor for organisms provided with a calcareous test. At 3 km west of the disposal site, macrofauna is comparable to the reference station, whereas foraminifera still indicate environmental degradation, suggesting their higher sensitivity to this type of pollution. It appears that benthic foraminifera may add valuable information to open marine environmental monitoring.

Kongsfjord is an open glacial fjord on the west coast of Svalbard, where the influence of the West Spitzbergen current ameliorates the effects of high latitude (79°N). The fjord is heavily influenced by glacial discharges of meltwater, ice and till, and related environmental gradients in sediments from the glaciers to the open sea include sediment deposition, organic content and disturbance. Other factors, such as the formation and break up of sea ice, also affect benthic communities. In this study spatial patterns in nematode and macrofaunal communities, in samples collected using box-corers and van Veen grabs during a cruise in September 1997, are described, compared and contrasted. Non-parametric multivariate analyses demonstrate that there were clear differences in community structure between stations in both macrofaunal and nematode assemblages. At stations where macrofauna were sampled using both box-cores and grabs there were also significant differences between samples collected by different methods, although there is evidence that these were influenced in part by slight differences in sampling location. Some evidence of disturbance to macrofaunal assemblages in the centre of the fjord is apparent. Macrofaunal community composition varied most closely with a combination of depth and sediment C : N ratio, whereas that of nematodes varied most closely with C : N alone. Proportions of feeding groups of nematodes showed little variation along the fjord. There is no evidence of a specialised nematode assemblage inhabiting the part of the fjord subject to the heaviest deposition of sediment. The taxonomic distinctness of nematodes decreased with increasing distance from the source of disturbance. This is in contrast to studies showing that the taxonomic distinctness of nematodes tends to decrease with increasing anthropogenic stress.

To investigate the combined effects of decreasing taxonomic resolution (i.e. species, family, phylum), the use of different mesh-size (1.0 mm and 0.5 mm) and the type of samplers used (van Veen vs. corers taken by divers) on the quality of data obtained, a comparative study was undertaken with the overall aim of identifying cost efficient methods for routinely monitoring the ecological change caused by Mediterranean fish farming. The results clearly showed that information loss was relatively low as data were aggregated at higher taxonomic levels, particularly up to the level of family or even order. It was also found that the extra information gained by sieving samples through a 0.5 mm sieve did not improve the ability to distinguish the potentially impacted sites from the control stations. Finally, it was found that a relatively large proportion of the available information concerning the community structure such as abundance, biomass or diversity is lost when sampling is carried out with corers. A cost/benefit ratio analysis for the two sampling and the two sieving methods showed minimal values for the van Veen samples (for both sieve fractions) at the family level, indicating that analysis at this level gives the best balance between precision of the results and decrease in taxonomic effort. However, if the time needed to sort the samples is included in the analysis, then samples taken with corers using a 0.5 mm sieve and identified to families seems like a good compromise between precision and cost.

This paper provides a critical review of the main issues regarding the scientific principles underlying environmental monitoring of marine aquaculture operations and makes recommendations relevant to the implementation of best practice for the management of aquaculture in Europe. Given that a variety of cultured species and approaches are adopted in Europe, it is not possible, or indeed desirable, to devise prescriptive guidelines. Instead, this paper reviews how science informs monitoring and provides a framework for the development of a monitoring strategy of marine aquaculture operations that is flexible enough to be applicable to a variety of locations, species and situations.Traditionally environmental monitoring has concentrated on a few key physical and chemical variables and organisms. The trend now, however, is towards whole-system environmental assessment (e.g. CEC 2000; Osparcom 1998), including considerations of the assimilative capacity of specific systems and their ability to absorb and dilute perturbations. Against this background this paper addresses the following specific objectives:review of the rationale and scientific principles underlying current environmental monitoring with specific reference to marine aquaculture;evaluation of the links between monitoring and regulatory criteria, specifically consideration of environmental quality objectives and environmental quality standards, and the role of environmental impact assessmentsassessment of the role of codes of best conduct and practice, and environmental management systems in the management of aquaculture operations.The paper concludes by proposing a set of recommendations which will contribute towards the sustainable management of aquaculture operations, through the implementation of a more focused approach to environmental monitoring.

This paper presents the results from a sedimentary survey undertaken in July 1992 in the Sado estuary, western coast of Portugal. Sediment samples were taken at 14 sites, corresponding to four organic enrichment gradients, three of which are located close to harbour facilities or to industrial or urban effluent outfalls. The fourth site is located away from direct sources of anthropogenic disturbance. An integrated approach was conducted in order to study the quality status of the superficial sediments, and included 1. the analysis of sediment descriptors and contaminants (grain-size, total organic matter, heavy metals, PCBs), 2. the evaluation of toxicity, using bioluminescent bacteria and the Microtox® solid-phase protocol and 3. the study of macrofaunal communities structure and composition. Most of the sediments showed low IC50 values (high toxicity), while benthic macrofauna did not indicate community disturbance in most of the sites, nor the contaminants analysed provided explanation for the potential toxicity observed. Most of the sediments showed high fines content. A statistical significant relation between fines and IC50 values was found, indicating the sensitivity of the toxicity assessment method for granulometry. This sensitivity might explain the lack of agreement between the IC 50 values and the sediment chemistry-infaunal communities structure. The potential grain-size sensitivity was further analysed using another test sediment from which artificial samples with different sand∶fines ratios were prepared. It is concluded that extreme caution should be used when applying the solid-phase Microtox® protocol to assess the toxicity of natural sediments, covering a range of granulometry and contamination situations.

SynopsisThe aims, methods and techniques of the macrobenthic monitoring programme in Sullom Voe and Orka Voe are described together with an analysis of the data obtained from surveys that began in 1978 and continue to the present. The distribution of the benthic macrofauna is discussed in relation to the sedimentological and hydrocarbon data obtained and compared with data from other Shetland waters. The macrofauna is considered to be typical of five of the six Facies used to describe the communities of the voes around Shetland. The possible effects of the terminal operations on the macrofauna are assessed and it is concluded that the disturbance noted to the macrofauna in Garths Voe, close to the diffuser at Calback Ness and in Orka Voe, essentially follows the same pattern seen in modifications to Shetland macrofauna that occurs where naturally occurring organic carbon enrichment exists.

Energy flow through the major compartments of the ecosystem of the south-east Kattegat has been assessed based on observations made between 1985-1989. In this increasingly eutrophic semi-estuarine coastal area, energy inputs are dominated by autochthonous production during the spring and autumn bloom periods (>90%), and by allochthonous fluvial sources during the winter (>50%).An unbalanced annual carbon budget is presented, which demonstrates the predominance of infaunal benthic suspension feeders in the shallow areas (above 13 m), where their demand alone is 2.4 times the calculated carbon supply to the sediment. Benthic demand does not diminish below 13 m, but the proportion utilized by macrofaunal deposit feeder's and meiofauna increases with lower suspension feeder demand, emphasizing the close coupling between pelagos and benthos at all depths in this system. Excess benthic demand over planktonic production is assumed to be met by lateral imports across the system boundaries.Intermittent summer hypoxia below the halocline (mean depth 15 m) has a severe effect on the benthos of the area, leading to a reduction in epifaunal predation prior to the reduction of macrobenthic organisms. Such events lead to the temporary accumulation of sedimentary carbon before late autumnal mixing initiates the reoxygenation and eventual recolonization of the affected areas.Comparisons with published carbon budgets for the Chesapeake Bay and the Baltic Sea suggest major differences between the relative roles of pelagos and benthos in these systems. In the Baltic, which is fuelled predominantly by autochthonous processes, pelagic carbon flows are about 4 times those of the benthos. Allochthonous inputs predominate throughout much of the year in the Chesapeake Bay, where pelagic flows are proportionately 1.5 x those of the benthos, whereas in the SE Kattegat benthic flows exceed those within the pelagos by about 25%.The higher populations of epifaunal and nektonic predators found in the SE Kattegat system, as opposed to the other two systems, is a corollary of the greater energy flows through the benthic components. The demonstrable vulnerability to anoxia of these commercially important organisms emphasizes the sensitivity of such coastal systems to the consequences of increased nutrient inputs.

SynopsisA brief outline of the characteristics and habitat of marine sedimentary benthos is given together with a consideration of the factors influencing the structure and distribution of benthic communities and the role of larval strategies in influencing recruitment to such communities. The bearing these ecological factors have for the conservation of such communities in Scottish waters is discussed in the context of current and potential threats to their present stability and distributions. It is suggested that the rich communities of the fjordic and shelf areas of the western coast and island groups merit the greatest current concern for conservation, in the face of increasing pressures from a range of developmental actions.

The environmental characteristics of fjordic ecosystems are briefly summarized and the importance of basin morphometry and seasonality are emphasized. General system variability is discussed in terms of four defined fjordic types, and energy flow within subsystems is considered. The information available on mass balance studies in fjordic systems is assessed in terms of nitrogen and carbon budgets and used comparatively to assess the effects of latitude, stagnation and salinity on general energy flow through such systems. Some general conclusions as to the net imports and exports of energy to fjords are drawn.