Seasonal variability of benthic indices: an approach to test the applicability of different indices for ecosystem quality assessment

In recent studies, several benthic biological indices were developed or used to assess the ecological quality status of marine environments. In the present study the seasonal variability of several univariate and multimetric indices was studied on a monthly scale (September 2000 until May 2002) in different areas of the North Sea such as the German Bight, the Oyster Ground and the Dogger Bank. The stations were chosen to reflect a gradient in the hydrographic regime, temperature and organic matter supply. The seasonal variability was highest for the univariate indices such as the Shannon–Wiener Index and the Hurlbert Index. Thus, due to sensitivity to recruitment the corresponding ecological status ranged from ‘good’ to ‘poor’ depending on the season. For the multimetric indices such as the AMBI or the BQI the seasonal variability and the corresponding ecological status were low. The results are discussed concerning possible consequences for ecological quality assessment especially related to the Water Framework Directive (WFD).     

Benthic biodiversity indices versus salinity gradient in the southern Baltic Sea

The need to assess the environmental status of marine and coastal waters according to the EU Water Framework Directive (WFD) encouraged the design of specific biotic indices to evaluate the response of benthic communities to human-induced changes in water quality. In the present study three of these indices, the traditional Shannon Wiener Index (H') and the more recently published AMBI (AZTI' Marine Biotic Index) and BQI (Benthic Quality Index), were tested along a salinity gradient in the southern Baltic Sea. The comparison of the three indices demonstrates that in the southern Baltic Sea the ecological quality (EcoQ) classification based on macrozoobenthic communities as indicator greatly depends on the biotic index chosen. We found a significant positive relation between species number, H', BQI and salinity resulting in EcoQ status of "Bad", "Poor" or "Moderate" in areas with a salinity value below 10 psu. The AMBI was less dependent on salinity but appear to partly overestimate the EcoQ status. Presently none of these biotic indices appear to be adjusted for application in a gradient system as given in the southern Baltic Sea. A potential approach describing how to overcome this limitation is discussed.     

Water quality assessment by pollution-index method in the coastal waters of Hebei Province in western Bohai Sea, China

Sources of pollution discharges and water quality samples at 27 stations in 2006 in the coastal waters of Hebei Province, western Bohai Sea, have been analyzed in this study. Pollutant loads from industrial sewages have shown stronger impact on the water environment than those from the general sewages. Analysis indicates that pollution of COD is mainly resulted from land-based point pollutant sources. For phosphate concentration, non-point source pollution from coastal ocean (fishing and harbor areas) plays an important role. To assess the water quality conditions, Organic Pollution Index and Eutrophication Index have been used to quantify the level of water pollution and eutrophication conditions. Results show that pollution was much heavier in the dry season than flood season in 2006. Based on COD and phosphate concentrations, results show that waters near Shahe River, Douhe River, Yanghe River, and Luanhe River were heavily polluted. Water quality in the Qinhuangdao area was better than those in the Tangshan and Cangzhou areas.     

An approach to the assessment of local trace metal pollution in the Mediterranean marine atmosphere

Assessing the extent of local trace metal pollution in marine atmospheric particulates presents a number of difficulties, and one potential approach to the problem has been evaluated by reference to a series of aerosols from the lower troposphere over the Eastern Mediterranean. This region, which is less remote from the continents than open-ocean areas, has two significantly different atmospheric particulate catchments: being bordered in the north by nations having industrialized, semi-industrialized and rural economies, and in the south by the North African desert belt. The elemental chemistry of the particulates is illustrated in terms of the distributions of Fe and Pb, which are presented in the form of enrichment factor diagrams, and is shown to be essentially controlled by the dilution of a ‘European’ background material, common to ‘remote’ regions of the latitudinal belt, with crust-derived, desert components. Major local perturbations in the dilution relationship can occur when either crust-derived or pollutant components strongly dominate the total particulate population. The extent of these local perturbations can be tentatively assessed using appropriate enrichment factor diagrams, which offer a framework within which to interpret the elemental chemistry of marine atmospheric particulates providing sufficient data is available for their construction. By using such an EF diagram it is suggested that the Eastern Mediterranean atmospheric particulates have not suffered local pollution on a gross scale with respect to Pb.     

Structuring factors of the spatio-temporal variability of macrozoobenthos assemblages in a southern Mediterranean lagoon: How useful for bioindication is a multi-biotic indices approach?

The authors investigated the impact of the extension of the El Kantra Channel on the composition and structure of macrobenthic assemblages in Boughrara Lagoon (Gulf of Gabes, Tunisia along with the use of 4 biotic indices (AMBI, BENTIX, M-AMBI and TUBI). Thirteen stations were sampled seasonally in 2012–2013. Forty-one species were found in 2012–2013 not recorded in 2009–2010, including 20 species of polychaetes belonging to the trophic groups of deposit-feeders and carnivores which are expected to increase in areas disturbed by organic pollution. During the survey, we recorded a high fish mortality, essentially caused by the development of harmful algal blooms (HAB) which increased organic matter deposition, thus inducing polychaete development. This seems to weaken the bio-indicating power of biotic indices used here which, paradoxically, classified all sampled stations at a high ecological status. A review of these indices and their applicability to all marine environments is recommended.     

Regional applicability of seven meteorological drought indices in China

The definition of a drought index is the foundation of drought research. However, because of the complexity of drought, there is no a unified drought index appropriate for different drought types and objects at the same time. Therefore, it is crucial to determine the regional applicability of various drought indices. Using terrestrial water storage obtained from the Gravity Recovery And Climate Experiment, and the observed soil moisture and streamflow in China, we evaluated the regional applicability of seven meteorological drought indices: the Palmer Drought Severity Index (PDSI), modified PDSI (PDSI_CN) based on observations in China, self-calibrating PDSI (scPDSI), Surface Wetness Index (SWI), Standardized Precipitation Index (SPI), Standardized Precipitation Evapotranspiration Index (SPEI), and soil moisture simulations conducted using the community land model driven by observed atmospheric forcing (CLM3.5/ObsFC). The results showed that the scPDSI is most appropriate for China. However, it should be noted that the scPDSI reduces the value range slightly compared with the PDSI and PDSI_CN; thus, the classification of dry and wet conditions should be adjusted accordingly. Some problems might exist when using the PDSI and PDSI_CN in humid and arid areas because of the unsuitability of empiricalparameters. The SPI and SPEI are more appropriate for humid areas than arid and semiarid areas. This is because contributions of temperature variation to drought are neglected in the SPI, but overestimated in the SPEI, when potential evapotranspiration is estimated by the Thornthwaite method in these areas. Consequently, the SPI and SPEI tend to induce wetter and drier results, respectively. The CLM3.5/ObsFC is suitable for China before 2000, but not for arid and semiarid areas after 2000. Consistent with other drought indices, the SWI shows similar interannual and decadal change characteristics in detecting annual dry/wet variations. Although the long-term trends of drought areas in China detected by these seven drought indices during 1961–2013 are consistent, obvious differences exist among the values of drought areas, which might be attributable to the definitions of the drought indices in addition to climatic change.     

A Marine Biotic Index to Establish the Ecological Quality of Soft-Bottom Benthos Within European Estuarine and Coastal Environments

In this paper, a marine Biotic Index (BI) for soft-bottom benthos of European estuarine and coastal environments is proposed. This is derived from the proportions of individual abundance in five ecological groups, which are related to the degree of sensitivity/tolerance to an environmental stress gradient. The main difference with previously published indices is the use of a simple formula that produces a continuous Biotic Coefficient (BC) – which makes it more suitable for statistical analysis, in opposition with previous discreet biotic indices – not affected by subjectivity. Relationships between this coefficient and a complementary BI with several environmental variables are discussed. Finally, a validation of the proposed index is made with data from systems affected by recent human disturbances, showing that different anthropogenic changes in the environment can be detected through the use of this BI.     

Mathematical modeling of oil hydrocarbon transformations in different parts of the White Sea

The available observational data on variations of oil hydrocarbon concentrations in White Sea tributaries and in individual parts of the sea are analyzed, and the contributions of different external sources to marine environment pollution are evaluated. The results of calculations are used to determine the possible total input of hydrocarbons from additional potential sources—internal natural (production by microorganisms) and external anthropogenic (navigation and sea shipping), which are most active in the summer and autumn. The hydroecological CNPSi-model is used to reproduce the processes of pollution of nine areas in the White Sea by oil hydrocarbons and their subsequent biodegradation in the marine environment. The annual dynamics of hydrocarbon concentrations was calculated using the long-term annual observations of monthly variations of the temperature, light intensity, and transparency of water, data on the morphometry of sea areas (the squares, mean depths, and water volumes) and water exchange between the chosen areas, calculated by a hydrodynamic model. For large bays (Dvina, Kandalaksha), the calculated concentrations of oil hydrocarbons are shown to be in agreement with the available estimates (the mean and maximal concentrations). The annual variations of oil hydrocarbon concentrations; the biomasses, oxidation activity and bioproduction characteristics of oil hydrocarbon-oxidizing bacteria are characterized. The calculated internal fluxes of oil hydrocarbons (the inputs from different sources, horizontal transport, and biotransformation) were used to calculate their annual balances for individual areas and the sea as a whole, showing the balanced character of their fluxes with the total balance discrepancies for individual areas varying within 0.3–4.1%.     

Marine Pollution Prevention and Management in the East Asian Seas: A Paradigm Shift in Concept, Approach and Methodology

A brief analysis of the current situation pertaining to marine pollution prevention and management in the East Asian Seas is outlined, particularly focusing on pollution arising from both land and sea-based sources. This paper highlights the results of a Regional Programme supported by the Global Environment Facility (GEF) in addressing some of the key marine pollution management problems of the region. The Programme has made significant progress in the following areas: (a) successfully developed and tested working models on the application of integrated coastal management (ICM) in addressing land-based sources of pollution; (b) tested risk assessment and risk management methodologies for addressing pollution in the Straits of Malacca; (c) attained commendable records in the ratification of marine pollution-related conventions; (d) developed an operational modality for stronger public and private sector partnerships; (e) demonstrated the cost-effectiveness of marine pollution monitoring programs; (f) focused on capacity building at the local level, and (g) with the above achievements, it has illustrated a paradigm shift in concept, approach and methodology in addressing the mounting environmental pressure caused by increasing marine pollution loads.     

The use of Lagrangian trajectories for the identification of the environmentally safe fairways

We propose and test a method for the optimisation of marine fairways to minimise the risk to high-value areas, based on statistical analysis of Lagrangian trajectories of current-driven pollution transport. The offshore areas are quantified according to the probability of pollution released in these areas to reach vulnerable regions. The method contains an eddy-resolving circulation model, a scheme for tracking of Lagrangian trajectories, a technique for the calculation of quantities characterising the potential of different sea areas to supply adverse impacts, and routines to construct the optimum fairway. The gain is expressed in terms of the probability of pollution transport to the nearshore and the associated time (particle age). The use of the optimum fairway would decrease the probability of coastal pollution by 40% or increase the average time of reaching the pollution to the coast from 5.3 to about 9 days in the Gulf of Finland, the Baltic Sea.     

Development of a sustainable livelihood security model for storm-surge hazard in the coastal areas of Bangladesh

Coastal communities in Bangladesh are at great risk due to frequent cyclones and cyclone induced storm-surges, which damages inland and marine resource systems. In the present research, seven marginal livelihood groups including Farmers, Fisherman, Fry (shrimp) collectors, Salt farmers, Dry fishers, Forest resource extractors, and Daily wage labourers are identified to be extremely affected by storm- surges in the coastal area of Bangladesh. A livelihood security model was developed to investigate the security status of the coastal livelihood system in a participatory approach. In the model, livelihood security consists of five components: (1) Food, (2) Income, (3) Life & health, (4) House & properties, and (5) Water security. Analytical hierarchy process was followed to assess the livelihood security indicators based on respondents’ security options. The model was verified through direct field observation and expert judgment. The Livelihood Security Model yields a Livelihood Security Index which can be used for assessing and comparing the household security level (in %) of different livelihood groups in the storm-surge prone coastal areas. The model was applied with data from two major coastal areas (Cox’s Bazar and Satkhira) of Bangladesh and is applicable to other coastal areas having similar settings.     

Environmental assessment of a large industrial marine complex based on a community of benthic filter-feeders

Biological quality in a bay affected by man's activities was evaluated by means of the composition of assemblages of sponges and ascidians. Our results showed that the structure of these two groups of filter-feeders aided in discriminating between undisturbed and disturbed areas, establishing different "environmental health categories" from moderately to strongly disturbed areas, and in ascertaining the extension of the area of each "health category". We were able to divide the bay into four zones based on type of disturbance or anthropogenic source: (1) stations free of any source of disturbance, (2) stations under moderate disturbance, located close to industrial ports, millworks, etc., (3) stations that are under the direct influence of industrial wastes such as a power station and oil refinery, and (4) stations near strongly disturbed areas, influenced directly by harmful steelworks activities. We differentiated clearly between four large species assemblages, and related the composition of these assemblages to different kinds of disturbances. Thus, these species could be used to manage the marine environment in this bay by comparing the observed fauna, with expected fauna in an unstressed site. Moreover, the joint presence of the sponge Cliona vastifica and tunicate Policitor adriaticum seems always to indicate a more or less pristine environmental situation, functioning as bioindicators of normal conditions. We think that the use of specific bioindicators for monitoring disturbance is a valid tool to establish baselines to predict impacts associated with industrial development in many marine ecosystems. The advantages to monitoring communities on hard rocks versus sandy or muddy bottoms are also commented upon.     

Correlation assessment and monitoring of the potential pollutants in the surface sediments of Pyeongchang River, Korea

The study provides a baseline for the assessment of the organic and inorganic pollution specially, heavy metal contamination in the surface sediments of Pyeongchang River,South Korea.The assessment of the study areas was done with respect to metal pollution load,ecological risk and geoaccumulated risk.Based upon the used indices,a priority index(P_index) was used to rank the utmost contaminated sites.Though the concentrations of mercury in all sediments were below the guideline, the significant enriched contamination was observed by all applied indices.As expected,the values of pollution load index（PLI）,ecological risk index（RI） and geoaccumulation risk index(I_geo) demonstrated lower heavy metal contamination in upstream areas compared to the downstream. Admittedly,sediments were unpolluted to slightly-polluted according to PLI while high to extremely high ecological risks were observed in several sediment samples.Furthermore,all the samples were uncontaminated as per I_geo.After simplification of I_geo,the P_index,showed the utmost contaminated sediments with a value of 2.537.Notably,protective measures should be taken to the highly contaminated areas which are prioritized by P_index Admittedly,the maximum concentrations of total organic carbon,total nitrogen,inorganic nitrogen,total phosphorous,inorganic phosphorous,calcium, magnesium,sodium and potassium were significantly observed as 7.8×10⁴,3,185,36,1,032,3.7, 1,5163,2,881,669 and 4,076mg/kg accordingly.     

A multimetric index for assessment of aquatic ecosystem health based on macroinvertebrates for the Zio river basin in Togo

The use of multimetric indices as tools for assessing aquatic ecosystem health in most of the developing countries such as Togo is still lacking. To fill this gap, we developed a macroinvertebrates-based multimetric index for the Zio river basin of Togo. Forty-two sites were assessed for the development and the validation of the Multimetric Index of Zio River Basin (MMIZB). Thirty-nine candidate metrics belonging to four categories (composition metrics, functional feeding metrics, diversity metrics and tolerance measure metrics) were evaluated. After comprehensive multiple selection procedure, six core metrics were retained to provide the final MMIZB. The results showed that the MMIZB responded to a set of organic pollution (chemical oxygen demand, ammonium, total suspended solid) and hydromorphological alterations, which corresponded to a set of gradients of human pressures affecting the ecological integrity of Zio river basin water bodies (r = 0.78, p < 0.001). The final macroinvertebrate index well distinguished the reference sites and impaired sites of a validation data set (p < 0.001) and showed a significant relationship between water and habitat quality based on Prati’s index (r = 0.73, p < 0.001) and Multimetric Macroinvertebrates Index of Vietnam (MMI_Vietnam) (r = 0.88, p < 0.001). This work underlines the relevance of the MMIZB as an effective tool for biological monitoring and decision making in water management of Zio river basin.     

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

Three multi-metric benthic macrofauna indices were used to assess marine benthic ecological quality status (EcoQS) according to the European Water Framework Directive, in seven pollution gradients mainly, western Scandinavia. The impacts included organic load, hypoxia, metals, urban effluents and physical disturbance. The indices responded in a similar threshold fashion, irrespective of impact factor identity. Usually, the border between Good and Moderate EcoQS (G/M), is determined as some deviation from a reference situation. References, however, are difficult to find. An alternative procedure is described to estimate the G/M border, not requiring reference data. Thresholds, where faunal structure deterioration commences, were identified from non-linear regressions between indices and impact factors. Index values from the less impacted side of the thresholds were assumed to come from environments of Good and High EcoQS, and the 5th percentile of these data, was defined as the G/M border. Estimated G/M borders compared well with previous studies.     

Measuring the ecological integrity of an industrial district in the Amazon estuary, Brazil

The aim of the present study is to provide information on the ecological integrity of an industrial district located in the estuary of Pará River (Amazon estuary), by applying a selection of fish based multimetric indices of ecosystem integrity: Abundance Biomass Comparation (ABC); Biological Health Index; Estuarine Fish Community, Transitional Fish Classification and Estuarine Biotic Integrity Indexes. To evaluate the impacts of the industrial area and cargo terminal, three areas were considered: Zone 1, (maximum impact), Zone 2 (median risk) and Zone 3 (reference area). All the biological indices used were considered to be excellent indicators of the ecological integrity of the different sectors of the study area and were especially effective for the demonstration of the critical alterations of the fish community of Zone 1 and Zone 2. The simultaneous use of different indices family, with different assumptions, did strengthen the results enhancing the confidence in the diagnostic.     

The nematode/copepod ratio some anomalous results from the Firth of Clyde

An analysis is presented of some intertidal meiofauna assemblages from the Firth of Clyde. The results cast doubt on the validity of the nematode/copepod ratio as a means of assessing marine pollution. In the light of this analysis, data from the literature on the meiofauna assemblages of the Firth of Clyde are reinterpreted. It is concluded that the ratio is unreliable because (a) it oversimplifies a highly complex set of relationships and (b) nematode and copepod populations may react independently to a variety of environmental parameters, of which pollution is only one. In these circumstances it is suggested that the ratio should be abandoned as a practical pollution indicator.     

Testing BOPA index in sewage affected soft-bottom communities in the north-western Mediterranean

The implementation of the European directive (ELD) 2000/60/EC has produced the development of several biotic indices based in benthic communities. These indices try to summarise ecological quality status of different communities. However, a universal index that works in all situations is difficult to establish, because there are several sources of variation. Therefore, there is the need for testing and validation of these indices which is required for making management decisions on different scales, and in different regions and communities. In this study we test one of these indices, BOPA index, developed by Dauvin and Ruellet [Dauvin, J.C., Ruellet, T., 2007. Polychaete/amphipod ratio revisited. Marine Pollution Bulletin 55, 215-224] in five locations affected by sewage disposal. These disposals are often released via outfall into shallow subtidal habitats, leading to a common source of pollution in coastal marine environments. BOPA index provides a valuable overview of the gradient status of a benthic environment, discriminating between stations more affected by discharge. Nevertheless, BOPA index, used to establish the ecological quality status, seemed to overestimate the status and hence there is the need to calibrate the thresholds between EcoQs classes as defined for these medium-to-fine sand communities, which are characteristics of shallow sublittoral soft-bottoms of the north-western Mediterranean Sea.