Assessment of marine benthic quality change in gradients of disturbance: comparison of different Scandinavian multi-metric indices

Good-Moderate boundary setting for the environmental status assessment of the macrozoobenthos communities with the Benthic Quality Index (BQI) in the south-western Baltic Sea

The status assessment of the macrofauna community under the European Marine Strategy Framework Directive (MSFD) requires threshold values that mark the transition from good to moderate conditions (G-M boundaries). Using the example of the Benthic Quality Index (BQI) in the south-western Baltic Sea, we demonstrate the possibilities and restrictions of i) defining G-M boundaries using reference areas, historical data and a statistical method and ii) the subsequent evaluation of the resulting G-M boundaries using disturbance data. The historical data from the period 1911 to 1929 proved to be unsuitable for defining G-M boundaries due to their data quality. The G-M boundaries calculated using the statistical method delineated high disturbance values more reliably than those based on reference areas. We conclude that disturbance data are very useful to evaluate G-M boundaries for their suitability, but data on all state conditions are needed.

Spatial distribution of meiofaunal and macrofaunal assemblages in the tidal flats of the southern Korean coast in relation to natural and anthropogenic impacts

We investigated the spatial variability of macrofaunal and meiofaunal assemblages in intertidal flats on the southern coast of Korea. Abiotic and biotic samples were collected at five stations. The species richness, density, and composition of the assemblages differed significantly among stations. Nematoda and Annelida were the most dominant meiofaunal and macrofaunal taxa, respectively, although taxon dominance differed among stations. Distance-based linear models showed that sediment-related variables and heavy metals were the main environmental factors determining the spatial variability of the assemblages. Macrofauna had only sediment-related variables and heavy metals as major environmental factors, but meiofauna were also influenced by other environmental factors such as sea surface temperature, dissolved oxygen-related variables, and salinity. This study can provide basic ecological data for understanding the spatial distribution of macro-meiofaunal assemblages and aid in the development of marine environmental management strategies on the western south coast of Korea.

European coastal monitoring programmes may fail to identify impacts on benthic macrofauna caused by bottom trawling

Bottom trawling (hereafter trawling) is the dominant human pressure impacting continental shelves globally. However, due to ongoing data deficiencies for smaller coastal vessels, the effects of trawling on nearshore seabed ecosystems are poorly understood. In Europe, the Water Framework Directive (WFD) provides a framework for the protection and improvement of coastal water bodies. It requires member states to track the status of 'biological quality elements' (including benthic macrofauna) using WFD-specific ecological indicators. While many of these metrics are sensitive to coastal pressures such as nutrient enrichment, little is known about their ability to detect trawling impacts. Here, we analysed a comprehensive data set of 5885 nearshore benthic samples - spatiotemporally matched to high-resolution trawling and environmental data - to examine how these pressures affect coastal benthos. In addition, we investigated the ability of 8 widely-used benthic monitoring metrics to detect impacts on benthic biological quality. We found that abundance (N) and species richness (S) were strongly impacted by bottom trawling. A clear response to trawling was also observed for the WFD-specific Benthic Quality Index (BQI). Relationships between N and S, and trawling were particularly consistent across the study area, indicating sensitivity across varying environmental conditions. In contrast, WFD indices such as AZTIs Marine Biotic Index (AMBI), multivariate AMBI (M-AMBI), and the Danish Quality Index (DKI), were unresponsive to trawling. In fact, some of the most heavily trawled areas examined were classified as being of 'high/good ecological status' by these indices. A likely explanation for this is that the indices are calculated using species sensitivity scores, based on expected species response to eutrophication and chemical pollution. While the BQI also uses species sensitivity scores, these are based on observed responses to disturbance gradients comprising a range of coastal pressures. Given the prominent use of AMBI and DKI throughout Europe, our results highlight the considerable risk that the metrics used to assess Good Ecological Status (GES) under the WFD may fail to identify trawling impacts. As trawling represents a widespread source of coastal disturbance, fishing impacts on benthic macrofauna may be underestimated, or go undetected, in many coastal monitoring programmes around Europe.

Species and functional diversity of marine macrobenthic community and benthic habitat quality assessment in semi-enclosed waters upon recovering from eutrophication, Bohai Bay, China

This study investigated the structure and function of macrobenthic community in Bohai Bay upon improvement of water quality due to pollution abatement. A total of 166 species were collected in the summer and autumn sampling, with an increase in sensitive species recorded as compared to data from previous studies. While historical variations in species richness indicated signs of improvement in community structure, results of functional diversity indices revealed that the macrobenthic community in Bohai Bay was still in an early stage of recovery. From BIO-ENV analysis, habitat instability may hinder how community responded to water quality improvement. Results of the benthic habitat quality assessment also indicated that the ecological status in most areas of Bohai Bay was classified as good, while a few estuarine regions were categorized in a poor status.

Benthic Foraminiferal Indices and Environmental Quality Assessment of Transitional Waters: A Review of Current Challenges and Future Research Perspectives

Transitional waters straddle the interface between marine and terrestrial biomes and, among others, include fjords, bays, lagoons, and estuaries. These coastal systems are essential for transport and manufacturing industries and suffer extensive anthropogenic exploitation of their ecosystem services for aquaculture and recreational activities. These activities can have negative effects on the local biota, necessitating investigation and regulation. As a result of this, EcoQS (ecological quality status) assessment has garnered great attention as an essential aspect of governmental bodies’ legislative decision-making process. Assessing EcoQS in transitional water ecosystems is problematic because these systems experience high natural variability and organic enrichment and often lack information about their pre-human impact, baseline, or “pristine” reference conditions, knowledge of which is essential to many commonly used assessment methods. Here, foraminifera can be used as environmental sentinels, providing ecological data such as diversity and sensitivity, which can be used as the basis for EcoQS assessment indices. Fossil shells of foraminifera can also provide a temporal aspect to ecosystem assessment, making it possible to obtain reference conditions from the study site itself. These foraminifera-based indices have been shown to correlate not only with various environmental stressors but also with the most common macrofaunal-based indices currently employed by bodies such as the Water Framework Directive (WFD). In this review, we firstly discuss the development of various foraminifera-based indices and address the challenge of how best to implement these synergistically to understand and regulate human environmental impact, particularly in transitional waters, which have historically suffered disproportionate levels of human impact or are difficult to assess with standard EcoQS methods. Further, we present some case studies to exemplify key issues and discuss potential solutions for those. Such key issues include, for example, the disparate performance of multiple indices applied to the same site and a proper assignment of EcoQS class boundaries (threshold values) for each index. Disparate aptitudes of indices to specific geomorphologic and hydrological regimes can be leveraged via the development of a site characteristics catalogue, which would enable the identification of the most appropriate index to apply, and the integration of multiple indices resulting in more representative EcoQS assessment in heterogenous transitional environments. In addition, the difficulty in assigning threshold values to systems without analogous unimpacted reference sites (a common issue among many transitional waters) can be overcome by recording EcoQS as an ecological quality ratio (EQR). Lastly, we evaluate the current status and future potential of an emerging field, genetic biomonitoring, focusing on how these new techniques can be used to increase the accuracy of EcoQS assessment in transitional systems by supplementing more established morphology-based methods.

Long-term response of marine benthic fauna to thin-layer capping with powdered activated carbon in the Grenland fjords, Norway

The Grenland fjords in Norway have a long history of contamination by large emissions of dioxins and mercury. As a possible sediment remediation method in situ, thin-layer capping with powdered activated carbon (AC) mixed with clay was applied at two test sites at 30 m and 95 m depth in the Grenland fjords. This study presents long-term effects of the AC treatment on the benthic community structure, i.e. nine years after capping. Capping with AC significantly reduced the number of species, their abundance and biomass at the two test sites, compared to uncapped reference sites. At the more shallow site, the dominant brittle star species Amphiura filiformis disappeared shortly after capping and did not re-establish nine years after capping. At the deeper site, the AC treatment also caused long-lasting negative effects on the benthic community, but some recovery was observed after nine years. Ecological indices used to assess environmental status did not capture the impaired benthic communities caused by the capping. The present study is the first documentation of negative effects of powdered AC on marine benthic communities on a decadal scale. Our results show that the benefits of reduced contaminant bioavailability from capping with AC should be carefully weighed against the cost of long-term detrimental effects on the benthic community. More research is needed to develop a thin-layer capping material that is efficient at sequestering contaminants without being harmful to benthic species.

Developing benthic monitoring programmes to support precise and representative status assessments: a case study from the Baltic Sea

Benthic habitats and communities are key components of the marine ecosystem. Securing their functioning is a central aim in marine environmental management, where monitoring data provide the base for assessing the state of marine ecosystems. In the Baltic Sea, a > 50-year-long tradition of zoobenthic monitoring exists. However, the monitoring programmes were designed prior to the current policies, primarily to detect long-term trends at basin-scale and are thus not optimal to fulfil recent requirements such as area-based periodic status assessments. Here, we review the current monitoring programmes and assess the precision and representativity of the monitoring data in status assessments to identify routes for improvement. At present, the monitoring is focused on soft-bottoms, not accounting for all habitat types occurring in the Baltic Sea. Evaluating the sources of variance in the assessment data revealed that the component accounting for variability among stations forms the largest proportion of the uncertainty. Furthermore, it is shown that the precision of the status estimates can be improved, with the current number of samples. Reducing sampling effort per station, but sampling more stations, is the best option to improve precision in status assessments. Furthermore, by allocating the sampling stations more evenly in the sub-basins, a better representativity of the area can be achieved. However, emphasis on securing the long-term data series is needed if changes to the monitoring programmes are planned.

Impact of historical sulfide mine tailings discharge on meiofaunal assemblages (Portmán Bay, Mediterranean Sea)

Portmán Bay is one of the most contaminated and chronically impacted coastal marine areas of the world. Here, from the 1957 to 1990, about 60 million tons of mine tailings from the processing of sulfide ores were dumped directly at the shoreline. The resulting deposit provides a unique opportunity to assess the impact of mine tailings on coastal marine ecosystems after ca 30 years since the discharge has ceased. We investigated meiofaunal abundance, biomass and biodiversity along a gradient of metal concentration that overlaps with a bathymetric gradient from 30 to 60 m depth. Despite the localized presence of extremely high concentration of metals, the bay was not a biological desert, but, nevertheless, was characterized by evident signs of impact on benthic diversity. Meiofaunal variables increased significantly with decreasing metal contamination, eventually reaching values comparable to other uncontaminated coastal sediments. Our results show that mine tailings influenced the spatial distribution of meiofaunal taxa and nematode species composition. In particular, we report here that the bay was characterized by the dominance of nematode opportunistic species tolerant to high metal concentration. The effects of mine tailing discharge on meiofaunal biodiversity and composition were still evident ca 30 years after the end of the mining activities. Overall, this study provides new insights on the potential impact of mine tailings disposal and metal contamination in coastal sediments, and, can also contribute to predict the potential long-term consequences of ever-expanding deep-sea mining industry on benthic environments.

Macrofaunal colonization of mine tailings impacted sediments

An experiment was conducted to study and compare macrofaunal colonization of thin layers of mine tailings. Experimental boxes filled with marine sediments capped with mine tailings were placed on the seabed and subject to colonization for six and twelve months. Three Norwegian mine tailings, representative of major production processes, were used. In addition, one set of boxes served as control and was not treated with tailings. The layer thickness of the tailings was supposed to represent the thickness in the transition zone between the sea deposit itself and unaffected sediments. The most fine-grained tailings, which also contained flotation chemicals, showed a significantly lower colonization than the control and the other treatments. At the same time, all sediments were successfully colonized and rich in species. In general, the abundance of annelids was lower, while the abundance of mollusks was higher in the tailings-treatments than the controls. There were larger differences in faunal densities between the controls and tailings-treatments after six than twelve months, probably due to coverage by natural sedimentation and mixing of the thin tailings layer with the sediment underneath throughout the experiment. As the tailings initiated varying degree of effects on the benthos, there is expected to be a difference in how far the effects will extend outside the sea deposit. This is the first study where the colonization potential is systematically compared between various tailings, and as colonization is assumed a frequent and important mechanism for faunal restitution after disturbance events, the results are important for the management of tailings placements as well as with regard to other forms of disturbances associated with defaunated areas, like dredging and disposal of contaminated sediments.

A new index for the assessment of hydromorphology in transitional and coastal waters around Ireland

In assessing the overall status of individual water bodies the EU Water Framework Directive (WFD) requires member states to assess both ecological and chemical status. The ecological status of transitional and coastal (TraC) waters is based on the assessment of specific biological elements as well as supporting chemical, physico-chemical and hydromorphological elements. Hydromorphology of TraC waters is one of the basic features of marine and coastal ecosystems controlling the presence of biota. Human induced hydromorphological alterations and pressures can damage the ecology and functioning of aquatic ecosystems. Thirteen metrics were developed and combined to form a hydromorphological index, the Hydromorphological Quality Index (HQI). The index categorises a water body into 5 classes. Semi-qualitative and quantitative criteria were used to assign a morphological classification directly related to that of the WFD, i.e., high, good, moderate, poor and bad. Thirty-three transitional and coastal water bodies were assessed using HQI.

Substantial changes in the depth distributions of benthic invertebrates in the eastern Kattegat since the 1880s

Bottom trawling and eutrophication are well known for their impacts on the marine benthic environment in the last decades. Evaluating the effects of these pressures is often restricted to contemporary benthic data, limiting the potential to observe change from an earlier (preimpact) state. In this study, we compared benthic species records from 1884 to 1886 by CGJ Petersen with recent data to investigate how benthic invertebrate species in the eastern Kattegat have changed since preimpact time. The study shows that species turnover between old and recent times was high, ca. 50%, and the species richness in the investigation area was either unchanged or higher in recent times, suggesting no net loss of species. Elements of metacommunity structure analysis of datasets from the 1880s, 1990s, and 2000s revealed a clear change in the depth distribution structure since the 1880s. The system changed from a Quasi-nested/Random pattern unrelated to depth in the 1880s with many species depth ranges over a major part of the studied depth interval, to a Clementsian pattern in recent times strongly positively correlated with depth. Around 30% of the 117 species recorded both in old and in recent times, including most trawling-sensitive species, that is large, semiemergent species, showed a decrease in maximal depth of occurrence from the deeper zone fished today to the shallower unfished zone, with on average 20 m. Concurrently, the species category remaining in the fished zone was dominated by species less sensitive to bottom trawling like infauna polychaetes and small-sized Peracarida crustaceans, most likely with short longevity. The depth interval and magnitude of the changes in depth distribution and the changes in species composition indicate impacts from bottom trawling rather than eutrophication. Furthermore, the high similarity of results from the recent datasets 10 years apart suggests chronic impact keeping the system in an altered state.

Temporal changes in benthic macrofauna on the west coast of Norway resulting from human activities

Quantitative analyses of soft bottom invertebrate fauna from four Norwegian sill fjords show increased macrofaunal abundance, species richness, and a considerably changed benthic deep water macrofaunal composition in the inner parts of the fjord system. In retrospect, the analyses show significantly altered benthic macrofaunal community structure that was not reflected by the changes in the Shannon-Wiener diversity indices during regular monitoring. The observed changes are mainly due to an increased abundance of opportunistic species, especially of the polychaete Polydora sp. during the last 10-15 years which is correlated significantly to declining dissolved oxygen, rising temperature in the bottom water and increasing total organic matter in the sediment. Possible anthropogenic and climatic impact factors related to the observed macrofaunal changes and environmental consequences of the changes are discussed.

Environmental DNA metabarcoding of benthic bacterial communities indicates the benthic footprint of salmon aquaculture

We evaluated benthic bacterial communities as bioindicators in environmental impact assessments of salmon aquaculture, a rapidly growing sector of seafood industry. Sediment samples (n=72) were collected from below salmon cages towards distant reference sites. Bacterial community profiles inferred from DNA metabarcodes were compared to reference data from standard macrofauna biomonitoring surveys of the same samples. Deltaproteobacteria were predominant in immediate vicinity of the salmon cages. Along the transect, significant shifts in bacterial community structures were observed with Gammaproteobacteria dominating the less-impacted sites. Alpha- and beta-diversity measures of bacterial communities correlated significantly with macrofauna diversity metrics and with five ecological status indices. Benthic bacterial communities mirror the reaction of macrofauna bioindicators to environmental disturbances caused by salmon farming. The implementation of bacterial eDNA metabarcoding in future Strategic Framework Directives is an alternative cost-effective high-throughput biomonitoring solution, providing a basis for management strategies in a matter of days rather than months.

Interannual variability of soft-bottom macrobenthic communities of the NW Gulf of Mexico in relationship to the Deepwater Horizon oil spill

A 3-year research program was undertaken to assess potential environmental disturbance caused by the Deepwater Horizon oil spill to the soft-bottom macrobenthic communities within Mexican waters of the northwestern Gulf of Mexico. Community properties and temporal/spatial variability were analyzed besides toxicant parameters such as hydrocarbons and trace-metals. Overall infaunal density increased, taxa proportion changed, and small-size opportunistic organisms prevailed throughout the study. Annual abundance-biomass comparison (ABC) curves revealed progressive stress scenarios from moderate to severe. Concentrations of vanadium, nickel, cobalt, PAHs and AHs increased gradually over time. However, low correlations between benthic density and biogeochemical variables were determined. Initially, sedimentary properties were the main drivers of benthic community structure; subsequently, nickel, vanadium and PAHs, indicative of anthropogenic effect, were highlighted. Interannual variability in the macroinfauna was attributed to the synergy of several environmental factors. Undoubtedly, compounds derived from fossil fuels had a significant disturbance role, but their source remains uncertain.

Approaches for integrated assessment of ecological and eutrophication status of surface waters in Nordic Countries

We review approaches and tools currently used in Nordic countries (Denmark, Finland, Norway and Sweden) for integrated assessment of 'ecological status' sensu the EU Water Framework Directive as well as assessment of 'eutrophication status' in coastal and marine waters. Integration principles for combining indicators within biological quality elements (BQEs) and combining BQEs into a final-integrated assessment are discussed. Specific focus has been put on combining different types of information into indices, since several methods are currently employed. As a consequence of the variety of methods used, comparisons across both BQEs and water categories (river, lakes and coastal waters) can be difficult. Based on our analyses, we conclude that some principles and methods for integration can be critical and that a harmonised approach should be developed. Further, we conclude that the integration principles applied within BQEs are critical and in need of harmonisation if we want a better understanding of potential transition in ecological status between surface water types, e.g. when riverine water enters a downstream lake or coastal water body.

Reducing spatial variation in environmental assessment of marine benthic fauna

The Benthic Quality Index, BQI, is widely used for benthic quality assessment. Here, we investigated if spatial variation in the BQI can be reduced by accounting for the environmental factors instead of having different boundaries for different salinity regimes between status classes in the EU Water Framework Directive and Marine Strategy Framework Directive. For this purpose we tested salinity, sediment structure, and depth in a regression model to test their contribution to variations in BQI. The spatial variation in BQI was better explained by depth than by salinity or sediment structure. The proposed assessment method uses the residuals from the regression model between BQI and depth. With this method the variance in BQI between samples was reduced by 50% to 75% in the majority of situations. A method to establish the boundary between good and moderate status and how to derive EQR-values according to the WFD is presented.

Is there a possibility of ranking benthic quality assessment indices to select the most responsive to different human pressures?

Although a plethora of benthic indices exist, there is no agreement on what index or indices should be used by environmental managers to establish benthic quality. The objective of this investigation was to rank 35 benthic quality assessment indices used in different countries to evaluate the impact produced by 15 different human pressures (including multipressure, aquaculture, sewage discharges, eutrophication, physical alteration, chemical pollution, climate change, etc.). The ranking was determined by taking into account the coverage area of biogeographical provinces, number of citations testing a pressure and number of citations with significant correlation with pressure. We analysed 363 references, of which 169 showed quantitative data. Over a potential total score of 100, the highest values were obtained by the following indices: (i) AZTI's Marine Biotic Index (AMBI), which scored 77, tested by using 14 pressures in 14 provinces from the Arctic to tropical seas; (ii) multivariate AMBI (M-AMBI), which scored 74, tested with 12 pressures in 13 provinces; (iii) Bentix (BENTIX), which scored 68, tested with nine pressures in six provinces; (iv) Benthic Quality Index (BQI), which scored 66, tested with five pressures in seven provinces; and (v) Benthic Opportunistic Polychaetes Amphipods (BOPA) index, which scored 62, tested with eight pressures in six provinces.

The Quality of Rocky Bottoms index (CFR): a validated method for the assessment of macroalgae according to the European Water Framework Directive

The Quality of Rocky Bottoms index (CFR by its Spanish acronym) is a multimetric method used for the assessment of macroalgae communities in accordance to the European Water Framework Directive. In order to improve the precision and accuracy of the assessments, the index was adjusted using a continuous scoring system. The index was tested at 184 intertidal and 57 subtidal stations located in the Atlantic coasts of Spain, Portugal and France. The anthropogenic pressure level of the stations was estimated according to a semiquantitative scale based on the type of discharge, distance to the contaminant source and its magnitude. 70.5% of the stations were correctly assigned to their expected quality and only 5.8% were critically misclassified. The linear regression and weighted kappa analyses between the pressure levels and the CFR results showed highly significant correlations and very good agreement levels both at intertidal and subtidal areas.

Rapid macrofaunal colonization of water-based drill cuttings on different sediments

A field experiment was conducted to investigate how water-based drill cuttings and sediment type influence colonization of soft bottom communities. Bottom frames with trays containing defaunated sediments were placed at the seabed for 6 months to study colonization of macrofauna. Two different sediments (coarse and fine) were used, and 6 or 24 mm layer of water-based drill cuttings were added on top of these sediments. Some of the sediments were controls with no additions. In the end of the experiment, the oxygen availability in sediment porewater and macrofaunal abundance were reduced in treatments with 24 mm drill cuttings compared to controls. Tube-building annelids were particularly sensitive to drill cuttings. However, these responses were only minor, and notably, the drill cuttings initiated a weaker faunal response than sediment type and site of the bottom frame. Sediments capped with water-based drill cuttings thus showed a rapid colonization of macrofaunal communities.

Benthic diversity gradients and shifting baselines: implications for assessing environmental status

The increasing pressure on marine biodiversity emphasizes the importance of finding benchmarks against which to assess change. This is, however, a notoriously difficult task in estuarine ecosystems, where environmental gradients are steep, and where benthic biodiversity is highly variable in space and time. Although recent emphasis on diverse, healthy benthic communities in legislative frameworks has increased the number of indices developed for assessing benthic status, there is a lack of quantitative baselines in benthic diversity that would enable comparisons across broad spatial scales, encompassing different environmental settings and bioregions. By taking advantage of long-term monitoring data, spanning hundreds of stations over the past 40 years, we provide a comprehensive analysis of benthic a, beta, and gamma diversity, encompassing the entire' salinity gradient of the open sea areas of the large, brackish-water Baltic Sea. Using a relatively simple measure, average regional diversity, we define area-specific reference conditions and acceptable deviation against which to gauge current conditions in benthic macrofaunal diversity. Results show a severely impaired condition throughout large areas of the Baltic for the assessment period 2001-2006. All ecosystems are plagued by baselines that shift in time and space, and their definition is not trivial, but average regional diversity may offer a transparent way to deal with such changes in low-diversity systems. Identifying baselines will be of increasing importance given the potential of climatic drivers to interact with local anthropogenic stressors to affect patterns of biodiversity. Our analysis provides an evaluation of the current condition in a system that has been heavily influenced by anthropogenic impact and changing oceanographic conditions, and it provides a basis for future impact assessment and ecosystem-based management.

Response of single benthic metrics and multi-metric methods to anthropogenic pressure gradients, in five distinct European coastal and transitional ecosystems

In recent times many benthic indices have been proposed to assess the ecological quality of marine waters worldwide. In this study we compared single metrics and multi-metric methods to assess coastal and transitional benthic status along human pressure gradients in five distinct environments across Europe: Varna bay and lake (Bulgaria), Lesina lagoon (Italy), Mondego estuary (Portugal), Basque coast (Spain) and Oslofjord (Norway). Hence, 13 single metrics (abundance, number of taxa, and several diversity and sensitivity indices) and eight of the most common indices used within the European Water Framework Directive (WFD) for benthic assessment were selected: index of size spectra (ISS), Benthic assessment tool (BAT), Norwegian quality index (NQI), Multivariate AMBI (M-AMBI), Benthic quality index (BQI), (Benthic ecosystem quality index (BEQI), Benthic index based on taxonomic sufficiency (BITS), and infaunal quality index (IQI). Within each system, sampling sites were ordered in an increasing pressure gradient according to a preliminary classification based on professional judgement. The different indices are largely consistent in their response to pressure gradient, except in some particular cases (i.e. BITS, in all cases, or ISS when a low number of individuals is present). Inconsistencies between indicator responses were most pronounced in transitional waters (i.e. IQI, BEQI), highlighting the difficulties of the generic application of indicators to all marine, estuarine and lagoonal environments. However, some of the single (i.e. ecological groups approach, diversity, richness) and multi-metric methods (i.e. BAT, M-AMBI, NQI) were able to detect such gradients both in transitional and coastal environments, being these multi-metric methods more consistent in the detection than single indices. This study highlights the importance of survey design and good reference conditions for some indicators. The agreement observed between different methodologies and their ability to detect quality trends across distinct environments constitutes a promising result for the implementation of the WFD's monitoring plans. Moreover, these results have management implications, regarding the dangers of misclassification, uncertainty in the assessment, use of conflicting indices, and testing and validation of indices.

Marine management--towards an integrated implementation of the European Marine Strategy Framework and the Water Framework Directives

Through implementing environmental Directives, Europe has moved towards coordinated and integrated catchment-to-coast management, following the most novel legislation on ecosystem-based approaches worldwide. The novel joint synthesis of this direction reviewed here allows us to regard the Water Framework Directive (WFD) as a 'deconstructing structural approach' whereas the Marine Strategy Framework Directive (MSFD) is a 'holistic functional approach', i.e. the WFD has split the ecosystem into several biological quality elements, then it compares the structure of these (such as species complement) individually before combining them and attempting to determine the overall condition. In contrast the MSFD concentrates on the set of 11 descriptors which together summarize the way in which the whole system functions. We emphasize that both Directives are frameworks on which many other directives are linked but that they need to be fully and seamlessly integrated to give a land to open sea system of assessment and management. Hence, by taking account of the experience gained in the WFD implementation, together with that from regional sea conventions, such as OSPAR (North East Atlantic) or HELCOM (Baltic Sea), we propose in this contribution an integrative approach for the environmental status assessment, within the MSFD.

The use of benthic indicators in Europe: from the Water Framework Directive to the Marine Strategy Framework Directive

The Water Framework Directive (WFD) and the Marine Strategy Framework Directive (MSFD) are the European umbrella regulations for water systems. It is a challenge for the scientific community to translate the principles of these directives into realistic and accurate approaches. The aim of this paper, conducted by the Benthos Ecology Working Group of ICES, is to describe how the principles have been translated, which were the challenges and best way forward. We have tackled the following principles: the ecosystem-based approach, the development of benthic indicators, the definition of 'pristine' or sustainable conditions, the detection of pressures and the development of monitoring programs. We concluded that testing and integrating the different approaches was facilitated during the WFD process, which led to further insights and improvements, which the MSFD can rely upon. Expert involvement in the entire implementation process proved to be of vital importance.