A low-cost, long-term underwater camera trap network coupled with deep residual learning image analysis.

Understanding long-term trends in marine ecosystems requires accurate and repeatable counts of fishes and other aquatic organisms on spatial and temporal scales that are difficult or impossible to achieve with diver-based surveys. Long-term, spatially distributed cameras, like those used in terrestrial camera trapping, have not been successfully applied in marine systems due to limitations of the aquatic environment. Here, we develop methodology for a system of low-cost, long-term camera traps (Dispersed Environment Aquatic Cameras), deployable over large spatial scales in remote marine environments. We use machine learning to classify the large volume of images collected by the cameras. We present a case study of these combined techniques' use by addressing fish movement and feeding behavior related to halos, a well-documented benthic pattern in shallow tropical reefscapes. Cameras proved able to function continuously underwater at deployed depths (up to 7 m, with later versions deployed to 40 m) with no maintenance or monitoring for over five months and collected a total of over 100,000 images in time-lapse mode (by 15 minutes) during daylight hours. Our ResNet-50-based deep learning model achieved 92.5% overall accuracy in sorting images with and without fishes, and diver surveys revealed that the camera images accurately represented local fish communities. The cameras and machine learning classification represent the first successful method for broad-scale underwater camera trap deployment, and our case study demonstrates the cameras' potential for addressing questions of marine animal behavior, distributions, and large-scale spatial patterns.

Aquatic life criteria derivation and ecological risk assessment of DEET in China.

N,N-diethyl-meta-toluamide (DEET) is the most widely used active ingredient in commercial insect repellents. In addition to its adverse effects in insects, DEET can affect non-target organisms in surface water systems. Nevertheless, the aquatic life criteria of DEET are not available. This study conducted both acute and chronic toxicity tests on DEET in native Chinese aquatic species, and derived its criterion maximum concentration (CMC) and criterion continuous concentration (CCC). The determined CMC and CCC of DEET were 21.53 and 0.52 mg/L, respectively. The toxicity data indicated that DEET exposure posed a higher toxicity to some algae than other aquatic species. Compared with other insect repellents, DEET exposure posed a moderate toxicity to aquatic species. Therefore, the exposure concentration of DEET in Chinese surface water was collected to assess the potential ecological risk. The preliminary ecological risk assessment showed that DEET posed negligible risk to aquatic ecosystems in China. However, considering its toxic effects on the growth and reproduction to aquatic organisms, the ecological risk posed by DEET is worth further concern.

Risk assessment of plastic pollution on marine diversity in the Mediterranean Sea.

Plastic marine pollution is an increasing threat to global marine diversity. Quantifying this threat is particularly difficult and complex, especially when evaluating multiple species with different ecological requirements. Here, we examine the semi-enclosed basin of the Mediterranean Sea where the inputs of plastic pollution and its impact on marine diversity are still widely unknown. Eighty-four species from six taxonomic classes were evaluated to assess the risk of ingesting plastic marine debris, integrating inter-specific factors such as plastic exposure rates and life history traits (e.g., motility, habitat, and body size). Species were modelled within a spatial context to identify and estimate their exposure to plastic ingestion across the Mediterranean Sea using literature data, species distribution maps and plastic dispersion models. Our approach identified hotspots for the risk of plastic ingestion across multiple taxa in the Mediterranean Sea, highlighting that coastal species are at higher risk of ingesting plastic in the marine environment than open-sea species. The plastic exposure analysis indicated that species with larger home ranges were more at risk of exposure with increased distances while local species were more likely to be exposed to plastic closer to the centre of their home range location. The approach used in this study can be applied to support management and mitigation efforts throughout the Mediterranean Sea and in other geographic regions to minimize the impact of plastic pollution on marine diversity.

River health assessment of the Yellow River source region, Qinghai-Tibetan Plateau, China, based on tolerance values of macroinvertebrates.

For decades, the river health of the Yellow River source region (YRSR) on the Qinghai-Tibetan Plateau has been a focal issue owing to its unique geographic location and ecological functions. This study investigated the ecological status of the headwater streams, the main stem, and the tributaries of the Yellow River in the YRSR using the tolerance values of macroinvertebrates and those related to biotic indices. The macroinvertebrate assemblages of the headwater streams were characterized by lower biodiversity than the tributaries downstream, based on comparisons of taxonomical composition, functional feeding group composition, and the pollution-tolerant capacity of taxa. The headwater streams had a lower ratio (16%) of pollution-sensitive macroinvertebrate taxa than that of the tributaries downstream (30%). The biotic indices (family- and genus-level biotic indices) indicated that the ecological health of the headwater streams was comparably poorer than that of the downstream tributaries. The combined effect of vulnerable natural conditions and increasing human disturbance is likely the main cause of eco-environmental degradation in the Yellow River headwater streams.

Species sensitivity distributions for use in environmental protection, assessment, and management of aquatic ecosystems for 12 386 chemicals.

The present study considers the collection and use of ecotoxicity data for risk assessment with species sensitivity distributions (SSDs) of chemical pollution in surface water, which are used to quantify the likelihood that critical effect levels are exceeded. This fits the European Water Framework Directive, which suggests using models to assess the likelihood that chemicals affect water quality for management prioritization. We derived SSDs based on chronic and acute ecotoxicity test data for 12 386 compounds. The log-normal SSDs are characterized by the median and the standard deviation of log-transformed ecotoxicity data and by a quality score. A case study illustrates the utility of SSDs for water quality assessment and management prioritization. We quantified the chronic and acute mixture toxic pressure of mixture exposures for >22 000 water bodies in Europe for 1760 chemicals for which we had both exposure and hazard data. The results show the likelihood of mixture exposures exceeding a negligible effect level and increasing species loss. The SSDs in the present study represent a versatile and comprehensive approach to prevent, assess, and manage chemical pollution problems. Environ Toxicol Chem 2019;38:905-917. © 2019 SETAC.

Molecular assessment of wild populations in the marine realm: Importance of taxonomic, seasonal and habitat patterns in environmental monitoring.

Scientists are currently faced with the challenge of assessing the effects of anthropogenic stressors on aquatic ecosystems. Cellular stress response (CSR) biomarkers are ubiquitous and phylogenetically conserved among metazoans and have been successfully applied in environmental monitoring but they can also vary according to natural biotic and abiotic factors. The reported variability may thus limit the wide application of biomarkers in monitoring, imposing the need to identify variability levels in the field. Our aim was to carry out a comprehensive in situ assessment of the CSR (heat shock protein 70 kDa, ubiquitin, antioxidant enzymes) and oxidative damage (lipid peroxidation) in wild populations across marine taxa by collecting fish, crustaceans, mollusks and cnidarians during two different seasons (spring and summer) and two habitat types (coast and estuary). CSR end-point patterns were different between taxa with mollusks having higher biomarker levels, followed by the cnidarians, while fish and crustaceans showed lower biomarker levels. The PCA showed clear clusters related to mobility/sessile traits with sessile organisms showing greater levels (>2-fold) of CSR proteins and oxidative damage. Mean intraspecific variability in the CSR measured by the coefficient of variation (% CV) (including data from all seasons and sites) was elevated (35-94%). Overall, there was a seasonal differentiation in biomarker patterns across taxonomic groups, especially evident in fish and cnidarians. A differentiation in biomarker patterns between habitat types was also observed and associated with phenotypic plasticity or local adaptation. Overall, specimens collected in the estuary had lower biomarker levels when compared to specimens collected in the coast. This work highlights the importance of assessing baseline biomarker levels across taxa, seasons and habitats prior to applying biomarker analyses in environmental monitoring. Selecting bioindicator species, defining sampling strategies, and identifying confounding factors are crucial preliminary steps that ensure the success of biomarkers as powerful tools in biomonitoring.

Assessment of the single and mixture ecotoxicity of pharmaceuticals of environmental concern using aquatic test organisms / Avaliação da ecotoxicidade individual e das misturas de fármacos de preocupação ambiental usando organismos-teste aquáticos

Pharmaceuticals are contaminants of emerging concern which have been a target of increasing attention by the scientific community. Pharmaceuticals presenting high consumption, incomplete metabolism and incomplete removal at wastewater treatment plants have been frequently detected in aquatic ecosystems worldwide. This is the case of the pharmaceuticals metformin (MET), bisoprolol (BIS), sotalol (SOT) and ranitidine (RAN). However, ecotoxicity data for these contaminants are scarce, especially regarding behavior effects and chronic toxicity. In addition, the knowledge regarding the joint toxicity of these pharmaceuticals on non-target organisms is still incipient, which makes their environment risk assessment uncertain. This study aimed to fill these knowledge gaps for these four pharmaceuticals, by carrying out toxicity tests using five test organisms from three trophic levels. Different endpoints were assessed in tests with Raphidocelis subcapitata (algae), Lemna minor (macrophyte), Daphnia similis (crustacean), Hydra attenuate (cnidarian) and Danio rerio (fish). The binary and quaternary mixture acute toxicity for these pharmaceuticals were assessed on D. similis and D. rerio embryo tests, respectively. This study also aimed to evaluate the predictive accuracy of the Concentration addition (CA) and the Independent action (IA) classic models. In addition, the nature of the possible toxicological interactions between the pharmaceuticals in binary mixtures were also evaluated, using the Combination Index-isobologram (CI) method. The modelling of the concentration-response curves and the associated statistical analyses were performed using the automated spreadsheet ToxCalcMix v.1.0 and the software OriginPro 2015. The software CompuSyn was used for performing the mixture analyses with the CI method. The experimental planning of the binary mixture tests was performed using the fractioned factorial design, in order to cover several possible ratio and level-dependent effects with a reduced number of test organisms. The results obtained in this study are shown in four articles. In article 1, we provided a critical review and discussed the misunderstandings, deficiencies and data gaps on the ecotoxicity data of pharmaceuticals and personal care products mixtures published in the literature. In the following articles, the results obtained from the single and mixture toxicity tests performed in this study were presented and discussed. The pharmaceuticals MET (article 2) and BIS (article 3) were classified as hazardous to the aquatic environment, in the acute toxicity category. However, an ecological risk is not expected for the pelagic freshwater species exposed to these two pharmaceuticals, based on the chronic data obtained. The results obtained from the mixture toxicity tests (article 4) showed that most of the observed toxicity effects from the binary mixtures were in the zone between the predicted effects by the CA and IA models. The CI model showed to be an useful tool to describe the possible toxicological interactions occurring between the pharmaceuticals in joint action. Even statistically significant non-effect concentrations of the pharmaceuticals added up to induce significant adverse effects in mixtures (something from nothing). It was concluded that ecological risk assessment based on single toxic effects can underestimate the real impact of environmental contaminants on aquatic ecosystems

A contaminação ambiental por fármacos tem sido alvo de crescente preocupação pela comunidade científica. Fármacos de elevado consumo, incompleto metabolismo e remoção incompleta em estações de tratamento de esgoto, como é o caso da metformina (MET), bisoprolol (BIS), sotalol (SOT) e ranitidina (RAN), têm sido frequentemente detectados em matrizes aquáticas do mundo todo. Apesar disso, dados ecotoxicológicos consistentes para esses contaminantes são escassos, principalmente com relação a efeitos comportamentais e oriundos de estudos crônicos. Além disso, o entendimento dos efeitos de suas ações combinadas em organismos não-alvo é ainda incipiente, o que gera incertezas na avaliação dos seus riscos ambientais. Esta pesquisa teve por objetivo preencher essas lacunas de conhecimentos para esses quatro fármacos, por meio da realização de testes com cinco diferentes organismos-teste de três diferentes níveis tróficos. Foram analisados diferentes parâmetros avaliativos em testes com os organismos aquáticos Raphidocelis subcapitata (alga), Lemna minor (macrófita), Daphnia similis (crustáceo), Hydra attenuata (cnidário) e Danio rerio (peixe). As toxicidades agudas das misturas binárias e quaternárias desses quatro fármacos também foram avaliadas em testes com D. similis e embriões de D. rerio, respectivamente. Este trabalho também teve por objetivo avaliar a acurácia preditiva dos modelos de adição de concentração (CA) e ação independente (IA) e analisar a natureza das possíveis interações toxicológicas entre os fármacos, em misturas binárias, usando o modelo do Índice de Combinação (CI). A modelagem das relações concentração-resposta e as análises estatísticas associadas foram realizadas empregando-se a planilha automatizada ToxCalcMix versão 1.0 e o software OriginPro 2015. O software CompuSyn foi utilizado para as análises envolvendo o CI. O planejamento experimental dos testes de misturas binárias foi realizado por meio do design fatorial fracionado, a fim de cobrir diversas possíveis interações em várias proporções e níveis de efeitos, com a redução do número de organismos-teste. Os resultados desta pesquisa estão apresentados em quatro artigos. No artigo 1, realizou-se uma revisão crítica com relação às lacunas de conhecimentos e deficiências identificadas a partir da análise da literatura sobre a ecotoxicologia de misturas de fármacos e de produtos de higiene pessoal. Nos artigos seguintes, foram apresentados e discutidos os resultados oriundos dos testes com os quatro fármacos avaliados neste estudo. Os fármacos MET (artigo 2) e BIS (artigo 3) foram classificados como perigosos para o ambiente aquático, na categoria de toxicidade aguda. Contudo, um risco ecológico não é esperado para as espécies pelágicas de água doce expostas a esses dois fármacos, com base nos dados de toxicidade crônica obtidos. Os resultados dos testes de misturas (artigo 4) permitiram concluir que a maior parte dos efeitos observados das misturas binárias estiveram na zona entre os efeitos preditos pelos modelos clássicos de CA e IA. O modelo do CI mostrou-se uma ferramenta útil para descrever a natureza das possíveis interações toxicológicas que ocorrem entre os fármacos em ações combinadas. Mesmo concentrações de nenhum efeito estatisticamente significativo dos fármacos causaram efeitos adversos significativos quando em misturas (something from nothing). Concluiu-se que avaliações de risco ecológicas baseadas em efeitos tóxicos individuais de contaminantes ambientais podem subestimar o real impacto desses compostos em ecossistemas aquáticos

The use of metabarcoding for meiofauna ecological patterns assessment.

Marine meiofauna comprises up to 22 phyla. Its morphological identification requires time and taxonomists' expertise, and molecular tools can make this task faster. We aim to disentangle meiofaunal diversity patterns at Araçá Bay by applying a model selection approach and estimating the effectiveness of metabarcoding (18S rDNA) and morphological methods for estimating the response of meiofauna diversity in small-scale interactions with environmental variables. A rarefaction curve indicated that ten samples were sufficient for estimating the total number of meiofauna OTUs in a tidal flat. In both approaches, richness was predicted by mean sand percentage, sediment sorting, and bacteria concentration. Nematode genera composition differed significantly between approaches, the result of taxonomic mismatch in the genetic database. The similarity between the model selected for diversity descriptors, the richness of nematode genera and meiofauna composition emphasized the utility of predictive models for metabarcoding estimates to detect small-scale interactions of these organisms.

Ecological thresholds of hypoxia and sedimentary H2S in coastal soft-bottom habitats: A macroinvertebrate-based assessment.

Ecological thresholds of dissolved oxygen (DO) and sedimentary hydrogen sulfide (H2S) for macrozoobenthos were examined during a 30-month monitoring of two stations in a highly eutrophic canal in inner Tokyo Bay, Japan. Bottom DO and H2S concentrations fluctuated seasonally, and were significantly correlated with water and sediment temperatures. Red tide-derived phytodetritus was a major source of sediment organic matters in the canal bottom, and the sediment became highly reduced and sulfidic condition in warmer months (sedimentary H2S; up to 8.5 mM). Dominant opportunistic taxa, including polychaetes and amphipods, were eliminated under low DO and high H2S conditions (i.e., population thresholds), and devastation of community structure occurred at 2.4-3.3 mg l-1 DO and 1.8-2.7 mM H2S (i.e., community thresholds). To maintain ecosystem function in anthropogenically degraded habitats and ensure colonization by macrozoobenthos throughout the year, DO and H2S levels should be maintained below these thresholds.

A big data approach to macrofaunal baseline assessment, monitoring and sustainable exploitation of the seabed.

In this study we produce a standardised dataset for benthic macrofauna and sediments through integration of data (33,198 samples) from 777 grab surveys. The resulting dataset is used to identify spatial and temporal patterns in faunal distribution around the UK, and the role of sediment composition and other explanatory variables in determining such patterns. We show how insight into natural variability afforded by the dataset can be used to improve the sustainability of activities which affect sediment composition, by identifying conditions which should remain favourable for faunal recolonisation. Other big data applications and uses of the dataset are discussed.

A novel framework for analyzing conservation impacts: evaluation, theory, and marine protected areas.

Environmental conservation initiatives, including marine protected areas (MPAs), have proliferated in recent decades. Designed to conserve marine biodiversity, many MPAs also seek to foster sustainable development. As is the case for many other environmental policies and programs, the impacts of MPAs are poorly understood. Social-ecological systems, impact evaluation, and common-pool resource governance are three complementary scientific frameworks for documenting and explaining the ecological and social impacts of conservation interventions. We review key components of these three frameworks and their implications for the study of conservation policy, program, and project outcomes. Using MPAs as an illustrative example, we then draw upon these three frameworks to describe an integrated approach for rigorous empirical documentation and causal explanation of conservation impacts. This integrated three-framework approach for impact evaluation of governance in social-ecological systems (3FIGS) accounts for alternative explanations, builds upon and advances social theory, and provides novel policy insights in ways that no single approach affords. Despite the inherent complexity of social-ecological systems and the difficulty of causal inference, the 3FIGS approach can dramatically advance our understanding of, and the evidentiary basis for, effective MPAs and other conservation initiatives.

Sympathy for the Devil: Detailing the Effects of Planning-Unit Size, Thematic Resolution of Reef Classes, and Socioeconomic Costs on Spatial Priorities for Marine Conservation.

Spatial data characteristics have the potential to influence various aspects of prioritising biodiversity areas for systematic conservation planning. There has been some exploration of the combined effects of size of planning units and level of classification of physical environments on the pattern and extent of priority areas. However, these data characteristics have yet to be explicitly investigated in terms of their interaction with different socioeconomic cost data during the spatial prioritisation process. We quantify the individual and interacting effects of three factors-planning-unit size, thematic resolution of reef classes, and spatial variability of socioeconomic costs-on spatial priorities for marine conservation, in typical marine planning exercises that use reef classification maps as a proxy for biodiversity. We assess these factors by creating 20 unique prioritisation scenarios involving combinations of different levels of each factor. Because output data from these scenarios are analogous to ecological data, we applied ecological statistics to determine spatial similarities between reserve designs. All three factors influenced prioritisations to different extents, with cost variability having the largest influence, followed by planning-unit size and thematic resolution of reef classes. The effect of thematic resolution on spatial design depended on the variability of cost data used. In terms of incidental representation of conservation objectives derived from finer-resolution data, scenarios prioritised with uniform cost outperformed those prioritised with variable cost. Following our analyses, we make recommendations to help maximise the spatial and cost efficiency and potential effectiveness of future marine conservation plans in similar planning scenarios. We recommend that planners: employ the smallest planning-unit size practical; invest in data at the highest possible resolution; and, when planning across regional extents with the intention of incidentally representing fine-resolution features, prioritise the whole region with uniform costs rather than using coarse-resolution data on variable costs.

Rapid assessment of target species: Byssate bivalves in a large tropical port.

Rapid assessment sampling for target species is a fast cost-effective method aimed at determining the presence, abundance and distribution of alien and native harmful aquatic organisms and pathogens that may have been introduced by shipping. In this study, the method was applied within a large tropical port expected to have a high species diversity. The port of Kaohsiung was sampled for bivalve molluscan species that attach using a byssus. Such species, due to their biological traits, are spread by ships to ports worldwide. We estimated the abundance and distribution range of one dreissenid (Mytilopsis sallei) and four mytilids (Brachidontes variabilis, Arcuatula senhousa, Mytilus galloprovincialis, Perna viridis) known to be successful invaders and identified as potential pests, or high-risk harmful native or non-native species. We conclude that a rapid assessment of their abundance and distribution within a port, and its vicinity, is efficient and can provide sufficient information for decision making by port managers where IMO port exemptions may be sought.

Non-use Economic Values for Little-Known Aquatic Species at Risk: Comparing Choice Experiment Results from Surveys Focused on Species, Guilds, and Ecosystems.

Accounting for non-market economic values of biological diversity is important to fully assess the benefits of environmental policies and regulations. This study used three choice experiments (species-, guild-, and ecosystem-based surveys) in parallel to quantify non-use values for little-known aquatic species at risk in southern Ontario. Mean willingness-to-pay (WTP) ranged from $9.45 to $21.41 per listing status increment under Canada's Species at Risk Act for both named and unnamed little-known species. Given the broad range of valuable ecosystem services likely to accrue to residents from substantial increases in water quality and the rehabilitation of coastal wetlands, the difference in WTP between species- and ecosystem-based surveys seemed implausibly small. It appeared that naming species-the 'iconization' of species in two of the three surveys-had an important effect on WTP. The results suggest that reasonable annual household-level WTP values for little-known aquatic species may be $10 to $25 per species or $10 to $20 per listing status increment. The results highlighted the utility of using parallel surveys to triangulate on non-use economic values for little-known species at risk.

Genetic assessment of meiobenthic community composition and spatial distribution in coastal sediments along northern Gulf of Mexico.

Meiobenthic (meiofauna and micro-eukaryotes) organisms are important contributors to ecosystem functioning in aquatic environments through their roles in nutrient transport, sediment stability, and food web interactions. Despite their ecological importance, information pertaining to variation of these communities at various spatial and temporal scales is not widely known. Many studies in the Gulf of Mexico (GOM) have focused either on deep sea or continental shelf areas, while little attention has been paid to bays and coastal regions. Herein, we take a holistic approach by using high-throughput sequencing approaches to examine spatial variation in meiobenthic communities within Alabama bays and the coastal northern GOM region. Sediment samples were collected along three transects (Mississippi Sound: MS, FOCAL: FT, and Orange Beach: OB) from September 2010 to April 2012 and community composition was determined by metabarcoding the V9 hypervariable region of the nuclear18S rRNA gene. Results showed that Stramenopiles (diatoms), annelids, arthropods (copepods), and nematodes were the dominate groups within samples, while there was presence of other phyla throughout the dataset. Location played a larger role than time sampled in community composition. However, samples were collected over a short temporal scale. Samples clustered in reference to transect, with the most eastern transect (OB) having a distinct community composition in comparison to the other two transects (MS and FT). Communities also differed in reference to region (Bay versus Shelf). Bulk density and percent inorganic carbon were the only measured environmental factors that were correlated with community composition.

A hierarchical classification of benthic biodiversity and assessment of protected areas in the Southern Ocean.

An international effort is underway to establish a representative system of marine protected areas (MPAs) in the Southern Ocean to help provide for the long-term conservation of marine biodiversity in the region. Important to this undertaking is knowledge of the distribution of benthic assemblages. Here, our aim is to identify the areas where benthic marine assemblages are likely to differ from each other in the Southern Ocean including near-shore Antarctica. We achieve this by using a hierarchical spatial classification of ecoregions, bathomes and environmental types. Ecoregions are defined according to available data on biogeographic patterns and environmental drivers on dispersal. Bathomes are identified according to depth strata defined by species distributions. Environmental types are uniquely classified according to the geomorphic features found within the bathomes in each ecoregion. We identified 23 ecoregions and nine bathomes. From a set of 28 types of geomorphic features of the seabed, 562 unique environmental types were classified for the Southern Ocean. We applied the environmental types as surrogates of different assemblages of biodiversity to assess the representativeness of existing MPAs. We found that 12 ecoregions are not represented in MPAs and that no ecoregion has their full range of environmental types represented in MPAs. Current MPA planning processes, if implemented, will substantially increase the representation of environmental types particularly within 8 ecoregions. To meet internationally agreed conservation goals, additional MPAs will be needed. To assist with this process, we identified 107 spatially restricted environmental types, which should be considered for inclusion in future MPAs. Detailed supplementary data including a spatial dataset are provided.

Environmental status assessment using DNA metabarcoding: towards a genetics based Marine Biotic Index (gAMBI).

Marine ecosystem protection and conservation initiatives rely on the assessment of ecological integrity and health status of marine environments. The AZTI's Marine Biotic Index (AMBI), which consists on using macroinvertebrate diversity as indicator of ecosystem health, is used worldwide for this purpose. Yet, this index requires taxonomic assignment of specimens, which typically involves a time and resource consuming visual identification of each sample. DNA barcoding or metabarcoding are potential harmonized, faster and cheaper alternatives for species identification, although the suitability of these methods for easing the implementation of the AMBI is yet to be evaluated. Here, we analyze the requirements for the implementation of a genetics based AMBI (gAMBI), and show, using available sequence data, that information about presence/absence of the most frequently occurring species provides accurate AMBI values. Our results set the basics for the implementation of the gAMBI, which has direct implications for a faster and cheaper marine monitoring and health status assessment.

The "one-out, all-out" principle entails the risk of imposing unnecessary restoration costs: a study case in two Mediterranean coastal lakes.

The Water Framework Directive uses the "one-out, all-out" principle in assessing water bodies (i.e., the worst status of the elements used in the assessment determines the final status of the water body). In this study, we assessed the ecological status of two coastal lakes in Italy. Indices for all biological quality elements used in transitional waters from the Italian legislation and other European countries were employed and compared. Based on our analyses, the two lakes require restoration, despite the lush harbor seagrass beds, articulated macrobenthic communities and rich fish fauna. The "one-out, all-out" principle tends to inflate Type I errors, i.e., concludes that a water body is below the "good" status even if the water body actually has a "good" status. This may cause additional restoration costs where they are not necessarily needed. The results from this study strongly support the need for alternative approaches to the "one-out, all-out" principle.

Assessment of the structural quality of streams in Germany--basic description and current status.

Fifteen years ago, the first mapping guidelines for the recording and evaluation of river physical habitat quality in Germany, closely following the Länder Arbeitsgemeinschaft Wasser (LAWA) field survey, have been published. In light of this experience, a revised version has now been developed for North Rhine-Westphalia (West Germany). For the assessment, the streams are divided into segments serving as survey units. The survey is performed primarily in the field from the mouth to the source by an on-site recording of data. Defined reference conditions of the relevant morphological stream types serve as basis of the evaluation. Two evaluation procedures are carried out independently to validate the quality of the data. The proven basic concept operates as follows: the local scale habitat variables are grouped into 31 single parameters, which are then aggregated into six main parameters. These can further be aggregated into three zones: streambed, banks and adjacent land. The main modifications of the presented version are the following: (1) a larger differentiation of morphological stream types and (2) a higher level of detail concerning the mapping of relevant habitat characteristics. The last point allows additional evaluation options related to the morphological needs of the instream biota and a differentiated survey of anthropogenic degradation. Despite all modifications, the comparability with previous surveys has been largely maintained. By qualitative comparison of this method with other European mapping guidelines, different concepts of hydromorphological mapping are finally discussed.

Tolerance values of benthic macroinvertebrates for stream biomonitoring: assessment of assumptions underlying scoring systems worldwide.

Tolerance values (TVs) based on benthic macroinvertebrates are one of the most widely used tools for monitoring the biological impacts of water pollution, particularly in streams and rivers. We compiled TVs of benthic macroinvertebrates from 29 regions around the world to test 11 basic assumptions about pollution tolerance, that: (1) Arthropoda are < tolerant than non-Arthropoda; (2) Insecta < non-Insecta; (3) non-Oligochaeta < Oligochaeta; (4) other macroinvertebrates < Oligochaeta + Chironomidae; (5) other macroinvertebrate taxa < Isopoda + Gastropoda + Hirudinea; (6) Ephemeroptera + Plecoptera + Trichoptera (EPT) < Odonata + Coleoptera + Heteroptera (OCH); (7) EPT < non-EPT insects; (8) Diptera < Insecta; (9) Bivalvia < Gastropoda; (10) Baetidae < other Ephemeroptera; and (11) Hydropsychidae < other Trichoptera. We found that the first eight of these 11 assumptions were supported despite regional variability. In addition, we examined the effect of Best Professional Judgment (BPJ) and non-independence of TVs among countries by performing all analyses using subsets of the original dataset. These subsets included a group based on those systems using TVs that were derived from techniques other than BPJ, and groups based on methods used for TV assignment. The results obtained from these subsets and the entire dataset are similar. We also made seven a priori hypotheses about the regional similarity of TVs based on geography. Only one of these was supported. Development of TVs and the reporting of how they are assigned need to be more rigorous and be better described.