Status and Causal Pathway Assessments Supporting River Basin Management

The European Water Framework Directive (WFD) requires a status assessment of all water bodies. If that status is deteriorated, the WFD urges the identification of its potential causes in order to be able to suggest appropriate management measures. The instrument of investigative monitoring allows for such identification, provided that appropriate tools are available to link the observed effects to causative stressors, while unravelling confounding factors. In this chapter, the state of the art of status and causal pathway assessment is described for the major stressors responsible for the deterioration of European water bodies, i.e. toxicity, acidification, salinisation, eutrophication and oxygen depletion, parasites and pathogens, invasive alien species, hydromorphological degradation, changing water levels as well as sediments and suspended matter. For each stressor, an extensive description of the potential effects on the ecological status is given. Secondly, stressor-specific abiotic and biotic indicators are described that allow for a first indication of probable causes, based on the assessment of available monitoring data. Subsequently, more advanced tools for site-specific confirmation of stressors at hand are discussed. Finally, the local status assessments are put into the perspective of the risk for downstream stretches in order to be able to prioritise stressors and to be able to select appropriate measures for mitigation of the risks resulting from these stressors.

Monitoring Programmes, Multiple Stress Analysis and Decision Support for River Basin Management

The identification of plausible causes for water body status deterioration will be much easier if it can build on available, reliable, extensive and comprehensive biogeochemical monitoring data (preferably aggregated in a database). A plausible identification of such causes is a prerequisite for well-informed decisions on which mitigation or remediation measures to take. In this chapter, first a rationale for an extended monitoring programme is provided; it is then compared to the one required by the Water Framework Directive (WFD). This proposal includes a list of relevant parameters that are needed for an integrated, a priori status assessment. Secondly, a few sophisticated statistical tools are described that subsequently allow for the estiation of the magnitude of impairment as well as the likely relative importance of different stressors in a multiple stressed environment. The advantages and restrictions of these rather complicated analytical methods are discussed. Finally, the use of Decision Support Systems (DSS) is advocated with regard to the specific WFD implementation requirements.

The SOLUTIONS project: challenges and responses for present and future emerging pollutants in land and water resources management.

SOLUTIONS (2013 to 2018) is a European Union Seventh Framework Programme Project (EU-FP7). The project aims to deliver a conceptual framework to support the evidence-based development of environmental policies with regard to water quality. SOLUTIONS will develop the tools for the identification, prioritisation and assessment of those water contaminants that may pose a risk to ecosystems and human health. To this end, a new generation of chemical and effect-based monitoring tools is developed and integrated with a full set of exposure, effect and risk assessment models. SOLUTIONS attempts to address legacy, present and future contamination by integrating monitoring and modelling based approaches with scenarios on future developments in society, economy and technology and thus in contamination. The project follows a solutions-oriented approach by addressing major problems of water and chemicals management and by assessing abatement options. SOLUTIONS takes advantage of the access to the infrastructure necessary to investigate the large basins of the Danube and Rhine as well as relevant Mediterranean basins as case studies, and puts major efforts on stakeholder dialogue and support. Particularly, the EU Water Framework Directive (WFD) Common Implementation Strategy (CIS) working groups, International River Commissions, and water works associations are directly supported with consistent guidance for the early detection, identification, prioritisation, and abatement of chemicals in the water cycle. SOLUTIONS will give a specific emphasis on concepts and tools for the impact and risk assessment of complex mixtures of emerging pollutants, their metabolites and transformation products. Analytical and effect-based screening tools will be applied together with ecological assessment tools for the identification of toxicants and their impacts. The SOLUTIONS approach is expected to provide transparent and evidence-based candidates or River Basin Specific Pollutants in the case study basins and to assist future review of priority pollutants under the WFD as well as potential abatement options.

Integrated economic-hydrologic analysis of policy responses

Water is a vital resource, but also a critical limiting factor for economic and social development in many parts of the world. The recent rapid growth in human population and water use for social and economic development is increasing the pressure on water resources and the environment, as well as leading to growing conflicts among competing water use sectors (agriculture, urban, tourism, industry) and regions (Gleick et al., 2009; World Bank, 2006). In Spain, as in many other arid and semi-arid regions affected by drought and wide climate variability, irrigated agriculture is responsible for most consumptive water use and plays an important role in sustaining rural livelihoods (Varela-Ortega, 2007). Historically, the evolution of irrigation has been based on publicly-funded irrigation development plans that promoted economic growth and improved the socio-economic conditions of rural farmers in agrarian Spain, but increased environmental damage and led to excessive and inefficient exploitation of water resources (Garrido and Llamas, 2010; Varela-Ortega et al., 2010). Currently, water policies in Spain focus on rehabilitating and improving the efficiency of irrigation systems, and are moving from technocratic towards integrated water management strategies driven by the European Union (EU) Water Framework Directive (WFD).

Participatory modeling for sustainable development in water and agrarian systems: potential and limits of stakeholder involvement

Public participation is increasingly advocated as a necessary feature of natural resources management. The EU Water Framework Directive (WFD) is such an example, as it prescribes participatory processes as necessary features in basin management plans (EC 2000). The rationale behind this mandate is that involving interest groups ideally yields higher-quality decisions, which are arguably more likely to meet public acceptance (Pahl-Wostl, 2006). Furthermore, failing to involve stakeholders in policy-making might hamper the implementation of management initiatives, as controversial decisions can lead pressure lobbies to generate public opposition (Giordano et al. 2005, Mouratiadou and Moran 2007).

Fish communities as indicators of biological conditions of rivers: methods for reference conditions

Fish communities are a key element in fluvial ecosystems Their position in the top of the food chain and their sensitivity to a whole range of impacts make them a clear objective for ecosystem conservation and a sound indicator of biological integrity. The UE Water Framework Directive includes fish community composition, abundance and structure as relevant elements for the evaluation os biological condition. Several approaches have been proposed for the evaluation of the condition of fish communities, from the bio-indicator concept to the IBI (Index of biotic integrity) proposals. However, the complexity of fish communities and their ecological responses make this evaluation difficult, and we must avoid both oversimplified and extreme analytical procedures. In this work we present a new proposal to define reference conditions in fish communities, discussing them from an ecological viewpoint. This method is a synthetic approach called SYNTHETIC OPEN METHODOLOGICAL FRAMEWORK (SOMF) that has been applied to the rivers of Navarra. As a result, it is recommended the integration of all the available information from spatial, modelling, historical and expert sources, providing the better approach to fish reference conditions, keeping the highest level of information and meeting the legal requirements of the WFD.

River Restoration in Spain: Theoretical and Practical Approach in the Context of the European Water Framework Directive.

River restoration is becoming a priority in many countries because of increasing the awareness of environmental degradation. In Europe, the EU Water Framework Directive (WFD) has significantly reinforced river restoration, encouraging the improvement of ecological status for water bodies. To fulfill the WFD requirements, the Spanish Ministry of the Environment developed in 2006 a National Strategy for River Restoration whose design and implementation are described in this paper. At the same time many restoration projects have been conducted, and sixty of them have been evaluated in terms of stated objectives and pressures and implemented restoration measures. Riparian vegetation enhancement, weir removal and fish passes were the most frequently implemented restoration measures, although the greatest pressures came from hydrologic alteration caused by flow regulation for irrigation purposes. Water deficits in quantity and quality associated with uncontrolled water demands seriously affect Mediterranean rivers and represent the main constraint to achieving good ecological status of Spanish rivers, most of them intensively regulated. Proper environmental allocation of in-stream flows would need deep restrictions in agricultural water use which seem to be of very difficult social acceptance. This situation highlights the need to integrate land-use and rural development policies with water resources and river management, and identifies additional difficulties in achieving the WFD objectives and good ecological status of rivers in Mediterranean countries.

Integrated assessment of policy interventions for promoting sustainable irrigation in semi-arid environments: A hydro-economic modeling approach

Sustaining irrigated agriculture to meet food production needs while maintaining aquatic ecosystems is at the heart of many policy debates in various parts of the world, especially in arid and semi-arid areas. Researchers and practitioners are increasingly calling for integrated approaches, and policy-makers are progressively supporting the inclusion of ecological and social aspects in water management programs. This paper contributes to this policy debate by providing an integrated economic-hydrologic modeling framework that captures the socio-economic and environmental effects of various policy initiatives and climate variability. This modeling integration includes a risk-based economic optimization model and a hydrologic water management simulation model that have been specified for the Middle Guadiana basin, a vulnerable drought-prone agro-ecological area with highly regulated river systems in southwest Spain. Namely, two key water policy interventions were investigated: the implementation of minimum environmental flows (supported by the European Water Framework Directive, EU WFD), and a reduction in the legal amount of water delivered for irrigation (planned measure included in the new Guadiana River Basin Management Plan, GRBMP, still under discussion). Results indicate that current patterns of excessive water use for irrigation in the basin may put environmental flow demands at risk, jeopardizing the WFD s goal of restoring the ?good ecological status? of water bodies by 2015. Conflicts between environmental and agricultural water uses will be stressed during prolonged dry episodes, and particularly in summer low-flow periods, when there is an important increase of crop irrigation water requirements. Securing minimum stream flows would entail a substantial reduction in irrigation water use for rice cultivation, which might affect the profitability and economic viability of small rice-growing farms located upstream in the river. The new GRBMP could contribute to balance competing water demands in the basin and to increase economic water productivity, but might not be sufficient to ensure the provision of environmental flows as required by the WFD. A thoroughly revision of the basin s water use concession system for irrigation seems to be needed in order to bring the GRBMP in line with the WFD objectives. Furthermore, the study illustrates that social, economic, institutional, and technological factors, in addition to bio-physical conditions, are important issues to be considered for designing and developing water management strategies. The research initiative presented in this paper demonstrates that hydro-economic models can explicitly integrate all these issues, constituting a valuable tool that could assist policy makers for implementing sustainable irrigation policies.

Estudio del estado de la vegetación de ribera en la España peninsular. Implicaciones de la alteración hidrológica y herramientas para su manejo y gestión

El objetivo general de este trabajo es explorar las potenciales interacciones entre la alteración hidrológica y el estado de la vegetación de ribera en diversas cuencas hidrográficas españolas. La mayor parte del área de estudio está dentro de la región Mediterránea, una región caracterizada por un particular comportamiento climatológico, ecológico y socio-económico. Las cuencas estudiadas son: Guadiana, Guadalquivir, Tajo, y Duero. Para complementar el estudio y comparar resultados con otras regiones climáticas españolas se estudiaron dos Demarcaciones atlánticas: Cantábrico y Miño-Sil. El funcionamiento fluvial, en las áreas mediterráneas, presenta grandes variaciones en el régimen hídrico, siendo uno de los principales controladores de la estructura, composición y distribución de la vegetación de ribera. Para investigar las interacciones mencionadas previamente, se presenta un nuevo índice, Riparian Forest Evaluation (RFV). El objetivo de este índice es valorar el estado de la vegetación de ribera en base a los principales controladores hidro-morfológicos responsables de la dinámica fluvial, y por tanto, relacionados con el desarrollo del corredor ribereño. RFV divide la evaluación del bosque de ribera en cuatro componentes: continuidad longitudinal, transversal, y vertical (dimensiones espaciales), y condiciones del regenerado (dimensión temporal). La clasificación final está basada en las mismas cinco clases fijadas por la Directiva europea Marco del Agua (DMA) (2000/60/CE) para valorar el estado ecológico de las masas de agua. La aplicación de este índice en 187 masas de agua ha mostrado su facilidad de aplicación y su consistencia desde un punto de vista legislativo y técnicocientífico. En paralelo al diseño del índice RFV, se ha desarrollado una nueva herramienta para dar apoyo a la evaluación del bosque de ribera (RFV) y la extracción de variables hidromorfológicas a escala de masa de agua en lugar de a escala local (muestreo de campo local). Se trata de Riparian Characterisation by LiDAR (RiC-DAR), que permite valorar el estado del bosque de ribera de una manera semiautomática, en un modo cuasi-continuo, usando LiDAR de alta resolución. Esto hecho permite mejorar significativamente la calidad y cantidad de información comparado con la toma de datos en campo, lo que permite reducir los recursos, particularmente cuando se trabaja a escala de masas de agua. Una de las potenciales causas de la degradación del bosque de ribera es la alteración hidrológica; así una vez se ha realizado la evaluación del bosque de ribera basada en elementos hidro-morfológicos ligados al régimen hídrico (RFV), se han identificado las potenciales relaciones entre la alteración hidrológica y la degradación de la vegetación riparia. Para ello, se requiere contar con series de aforos fiables y de una duración apropiada. Para satisfacer este requerimiento, se ha creado una nueva herramienta: el Servidor de Datos para el Estudio de la Alteración Hidrológica (SEDAH). Esta herramienta genera datos diarios y mensuales completados para más años, construyendo así bases de datos más aptas para el estudio de la alteración hidrológica. (http://ambiental.cedex.es/Sedah) Haciendo uso de las herramientas y métodos desarrollados previamente, se han calculado diferentes indicadores de alteración hidrológica en 87 masas de agua que han sido analizados conjuntamente con el estado de la vegetación de ribera. Los resultados estadísticos han mostrado relaciones significativas entre ellos: la degradación de la vegetación podría estar fuertemente ligada a la alteración del régimen hídrico en años secos y a las sequías en el entorno mediterráneo. A su vez se ha analizado la relación del estado del bosque de ribera con el estado ecológico basado en la DMA, mostrando una relación no significativa. Esta y otras potenciales relaciones son discutidas a lo largo del documento. Los resultados permiten proponer recomendaciones de gestión de la vegetación de ribera y de manejo del régimen de caudales para masas de agua reguladas. ABSTRACT The general objective of this work is to explore the potential interactions between hydrologic alteration and degradation of the riparian vegetation, mainly focused in the Mediterranean Environment. The majority of the study area is part of the Spanish Mediterranean region, a geographical environment characterized by a singular climatologic, ecological and socio-economical behavior. The basins analysed in this work are: Guadiana, Guadalquivir, Tagus, Douro. In order to complete the results and compare those to other climatic regions in Spain, two Atlantic Districts where selected: Cantábrico and Miño-Sil. The river functioning, in the Mediterranean areas, presents great variations in the flow regimes being one of the main drivers of the riparian vegetation development. To explore the interactions stated above, a new index is presented, Riparian Forest Evaluation (RFV). This index is aimed to assess the status of the riparian vegetation based on the main hydromorphological drivers responsible of the river dynamic, and so, related to the development of the riparian corridor. RFV split the evaluation of the riparian forest into four components: longitudinal continuity, transversal continuity, vertical (structure) continuity and regeneration (temporal) continuity. The final classification is based in the same five classes to those stated in the European Water Frame Work directive to assess the ecological status. The application of this index over 187 water bodies has shown to be easily applicable and consistent from a regulatory perspective. In parallel to the design of RFV, a new tool has been developed to enhance the evaluation of the riparian forest and river morphology (RFV and morphological parameters) at water body scale rather than at local scale, i.e. when field surveyed at different sites. The Riparian Characterisation by LiDAR, RiC-DAR allows to assess the status of the riparian vegetation semi-automatically in a quasi-continuous way using high resolution LiDAR. This improves significantly the quantity and quality of information gathered through field sampling methods, reducing resources when working at larger scales. One of the potential major causes of degradation of the riparian forest is the hydrologic alteration; hence, once the evaluation of the riparian forest is done consistently based on hydro-morphological features linked to the hydrological regime (RVF), this work has identified potential relationships between hydrologic alteration and degradation of riparian vegetation. In order to do this, it is required to count with reliable series of flow records describing both reference and altered regimes. To satisfy this need, a new tool has been created, SEDAH, data server for assessing hydrologic alteration. This tool has completed daily and monthly gaps in the flow series to build up an improved database to assess the hydrologic alteration. This application is available on line (http://ambiental.cedex.es). Making use of the tools and methods developed previously, this work uses these data to work out indicators of hydrologic alteration through 87 water bodies to be analysed against the riparian status. These indicators are statistically analysed exploring significant relationships with the status of riparian vegetation and ecological status, showing some potential significant relationships; hence it seems that the degradation of riparian vegetation, particularly the regeneration, is associated with the alteration of the hydrologic regimen in dry years and draughts in Mediterranean environments. Furthermore, the analysis of the status of the ecological status and the status of the riparian vegetation has shown the lack of significant influence of the riparian vegetation in the final ecological status using the WFD approach applied in Spain. This and other potential relationships are discussed in this work. The results allow giving guidance on the management of both riparian vegetation and environmental flows of water bodies affected by flow regulation.

Valutazione del rischio ecologico e sviluppo di strategie innovative per il monitoraggio della qualita’ dei corpi idrici: applicazione di un nuovo approccio integrato in un bacino pilota.

Freshwater is extremely precious; but even more precious than freshwater is clean freshwater. From the time that 2/3 of our planet is covered in water, we have contaminated our globe with chemicals that have been used by industrial activities over the last century in a unprecedented way causing harm to humans and wildlife. We have to adopt a new scientific mindset in order to face this problem so to protect this important resource. The Water Framework Directive (European Parliament and the Council, 2000) is a milestone legislative document that transformed the way that water quality monitoring is undertaken across all Member States by introducing the Ecological and Chemical Status. A “good or higher” Ecological Status is expected to be achieved for all waterbodies in Europe by 2015. Yet, most of the European waterbodies, which are determined to be at risk, or of moderate to bad quality, further information will be required so that adequate remediation strategies can be implemented. To date, water quality evaluation is based on five biological components (phytoplankton, macrophytes and benthic algae, macroinvertebrates and fishes) and various hydromorphological and physicochemical elements. The evaluation of the chemical status is principally based on 33 priority substances and on 12 xenobiotics, considered as dangerous for the environment. This approach takes into account only a part of the numerous xenobiotics that can be present in surface waters and could not evidence all the possible causes of ecotoxicological stress that can act in a water section. The mixtures of toxic chemicals may constitute an ecological risk not predictable on the basis of the single component concentration. To improve water quality, sources of contamination and causes of ecological alterations need to be identified. On the other hand, the analysis of the community structure, which is the result of multiple processes, including hydrological constrains and physico-chemical stress, give back only a “photograph” of the actual status of a site without revealing causes and sources of the perturbation. A multidisciplinary approach, able to integrate the information obtained by different methods, such as community structure analysis and eco-genotoxicological studies, could help overcome some of the difficulties in properly identifying the different causes of stress in risk assessment. In synthesis, the river ecological status is the result of a combination of multiple pressures that, for management purposes and quality improvement, have to be disentangled from each other. To reduce actual uncertainty in risk assessment, methods that establish quantitative links between levels of contamination and community alterations are needed. The analysis of macrobenthic invertebrate community structure has been widely used to identify sites subjected to perturbation. Trait-based descriptors of community structure constitute a useful method in ecological risk assessment. The diagnostic capacity of freshwater biomonitoring could be improved by chronic sublethal toxicity testing of water and sediment samples. Requiring an exposure time that covers most of the species’ life cycle, chronic toxicity tests are able to reveal negative effects on life-history traits at contaminant concentrations well below the acute toxicity level. Furthermore, the responses of high-level endpoints (growth, fecundity, mortality) can be integrated in order to evaluate the impact on population’s dynamics, a highly relevant endpoint from the ecological point of view. To gain more accurate information about potential causes and consequences of environmental contamination, the evaluation of adverse effects at physiological, biochemical and genetic level is also needed. The use of different biomarkers and toxicity tests can give information about the sub-lethal and toxic load of environmental compartments. Biomarkers give essential information about the exposure to toxicants, such as endocrine disruptor compounds and genotoxic substances whose negative effects cannot be evidenced by using only high-level toxicological endpoints. The increasing presence of genotoxic pollutants in the environment has caused concern regarding the potential harmful effects of xenobiotics on human health, and interest on the development of new and more sensitive methods for the assessment of mutagenic and cancerogenic risk. Within the WFD, biomarkers and bioassays are regarded as important tools to gain lines of evidence for cause-effect relationship in ecological quality assessment. Despite the scientific community clearly addresses the advantages and necessity of an ecotoxicological approach within the ecological quality assessment, a recent review reports that, more than one decade after the publication of the WFD, only few studies have attempted to integrate ecological water status assessment and biological methods (namely biomarkers or bioassays). None of the fifteen reviewed studies included both biomarkers and bioassays. The integrated approach developed in this PhD Thesis comprises a set of laboratory bioassays (Daphnia magna acute and chronic toxicity tests, Comet Assay and FPG-Comet) newly-developed, modified tacking a cue from standardized existing protocols or applied for freshwater quality testing (ecotoxicological, genotoxicological and toxicogenomic assays), coupled with field investigations on macrobenthic community structures (SPEAR and EBI indexes). Together with the development of new bioassays with Daphnia magna, the feasibility of eco-genotoxicological testing of freshwater and sediment quality with Heterocypris incongruens was evaluated (Comet Assay and a protocol for chronic toxicity). However, the Comet Assay, although standardized, was not applied to freshwater samples due to the lack of sensitivity of this species observed after 24h of exposure to relatively high (and not environmentally relevant) concentrations of reference genotoxicants. Furthermore, this species demonstrated to be unsuitable also for chronic toxicity testing due to the difficult evaluation of fecundity as sub-lethal endpoint of exposure and complications due to its biology and behaviour. The study was applied to a pilot hydrographic sub-Basin, by selecting section subjected to different levels of anthropogenic pressure: this allowed us to establish the reference conditions, to select the most significant endpoints and to evaluate the coherence of the responses of the different lines of evidence (alteration of community structure, eco-genotoxicological responses, alteration of gene expression profiles) and, finally, the diagnostic capacity of the monitoring strategy. Significant correlations were found between the genotoxicological parameter Tail Intensity % (TI%) and macrobenthic community descriptors SPEAR (p<0.001) and EBI (p<0.05), between the genotoxicological parameter describing DNA oxidative stress (ΔTI%) and mean levels of nitrates (p<0.01) and between reproductive impairment (Failed Development % from D. magna chronic bioassays) and TI% (p<0.001) as well as EBI (p<0.001). While correlation among parameters demonstrates a general coherence in the response to increasing impacts, the concomitant ability of each single endpoint to be responsive to specific sources of stress is at the basis of the diagnostic capacity of the integrated approach as demonstrated by stations presenting a mismatch among the different lines of evidence. The chosen set of bioassays, as well as the selected endpoints, are not providing redundant indications on the water quality status but, on the contrary, are contributing with complementary pieces of information about the several stressors that insist simultaneously on a waterbody section providing this monitoring strategy with a solid diagnostic capacity. Our approach should provide opportunities for the integration of biological effects into monitoring programmes for surface water, especially in investigative monitoring. Moreover, it should provide a more realistic assessment of impact and exposure of aquatic organisms to contaminants. Finally this approach should provide an evaluation of drivers of change in biodiversity and its causalities on ecosystem function/services provision, that is the direct and indirect contributions to human well-being.

Glaisdale Beck diversion scheme - channel change and suspended sediment response

This paper describes the implementation of a novel mitigation approach and subsequent adaptive management, designed to reduce the transfer of fine sediment in Glaisdale Beck; a small upland catchment in the UK. Hydro-meteorological and suspended sediment datasets are collected over a two year period spanning pre- and post-diversion periods in order to assess the impact of the channel reconfiguration scheme on the fluvial suspended sediment dynamics. Analysis of the river response demonstrates that the fluvial sediment system has become more restrictive with reduced fine sediment transfer. This is characterised by reductions in flow-weighted mean suspended sediment concentrations from 77.93 mg/l prior to mitigation, to 74.36 mg/l following the diversion. A Mann-Whitney U test found statistically significant differences (p < 0.001) between the pre- and post-monitoring median SSCs. Whilst application of one-way analysis of covariance (ANCOVA) on the coefficients of sediment rating curves developed before and after the diversion found statistically significant differences (p < 0.001), with both Log a and b coefficients becoming smaller following the diversion. Non-parametric analysis indicates a reduction in residuals through time (p < 0.001), with the developed LOWESS model over-predicting sediment concentrations as the channel stabilises. However, the channel is continuing to adjust to the reconfigured morphology, with evidence of a headward propagating knickpoint which has migrated 120 m at an exponentially decreasing rate over the last 7 years since diversion. The study demonstrates that channel reconfiguration can be effective in mitigating fine sediment flux in upland streams but the full value of this may take many years to achieve whilst the fluvial system, slowly readjusts.

Directive cadre sur l’eau - Bassin Loire-Bretagne. Contrôle de surveillance dans les masses d’eau côtières et de transition. Actions menées par Ifremer en 2014

Le contrôle de surveillance 2014 pour la DCE appliquée dans les eaux littorales de Loire Bretagne a porté sur les 25 masses d’eau côtières (sur 39 au total) et les 16 masses d’eau de transition (sur 30 au total) retenues au titre du contrôle de surveillance. L’ensemble des résultats acquis, aussi bien sur les paramètres biologiques que chimiques, a permis de mettre à jour l’évaluation de l’état des masses d’eau affiché sur l’atlas DCE accessible sur la page web d’Envlit correspondante.

Mineral and organic pollution in river Sabor (Northeastern Portugal): ecotoxicological effects on freshwater fauna

Aquatic ecosystems are final collectors of all kinds of pollution as an outcome of anthropogenic inputs, such us untreated industrial and municipal sewage and agricultural pollutants. There are several aquatic ecosystems that are threatened by mineral and organic pollution. In Northeastern Portugal, near Bragança, different watercourses are suffering negative impacts of human activities. It has been developed several studies in the monitoring of environmental impacts in these river basins, namely in Rio Fervença, affected by organic pollution, and in Portelo stream, affected, since 2009, by the collapse and continuous input of mining deposits. In this sense, the present study aimed to continue the monitoring study of ecological status of freshwater ecosystems of Northeastern Portugal, namely the following objectives: a) mineral pollution effects of mining deposits sudden incorporated into Portelo stream; b) organic pollution due to domestic and industrial inputs in River Fervença. Also, since fish are useful experimental models to evaluate toxicological mechanisms of contaminants, c) acute toxicity tests with Cu were conducted in laboratory conditions. During 2015/2016, it was made abiotic and biotic characterization of 16 sampling sites distributed by both Portelo and Fervença rivers, tributaries of main River Sabor (Douro Basin). Several physicochemical parameters were determined and Riparian Quality (QBR Index) and Channel Quality (GQC) Indexes were determined for habitat evaluation. Fish and invertebrate communities were sampled, according to protocols of Water Framework Directive (WFD). Several metrics were determined, with particular emphasis on the Biotic Index IBMWP and the Northern Portuguese Invertebrate Index (IPtIN). Acute toxicity tests were conducted with an Iberian fish species, common barbel (Luciobarbus bocagei) and some plasmatic electrolytes levels were evaluated, to assess their contribution to mitigate osmoregulatory adverse effects of Cu. Also, same electrolytes were measured after changing to clean water, in attempt to assess fish capacity to reverse this situation. Results obtained for both rivers showed a significant level of disturbance that affected decisively water, habitat and biological quality of aquatic ecosystems. Mineral and Organic Pollution in River Sabor (NE Portugal): Ecotoxicological Effects on Freshwater Fauna Due to this change of environmental conditions in Portelo stream (extreme pH values, high conductivity and presence of heavy metals), several biological metrics (e.g. taxonomic richness, abundance, diversity, evenness) confirmed, comparatively with reference sites, a substantial decrease on ecological integrity status. The same pattern was found for Fervença River; however other water parameters, namely the content of most limiting nutrients (e.g. N and P) seemed to have more influence in the composition and structure of macroinvertebrate and fish communities. In fact, despite the operation of the Sewage Treatment Plant of Bragança, Fervença River presented significant levels of disturbance that affected decisively the quality and ecological integrity of the aquatic ecosystem. The synergic effect of domestic and industrial pollution, intensive agriculture, regulation and degradation of aquatic and riparian habitats contributed to the decrease of ecological condition, namely in the downstream zones (after Bragança). The results for acute toxicity, showed that fish can change Na+ and K+ levels face to Cu exposition and, depending of Cu concentration tested, can also return to normal levels, providing some insights to that are believed to occurred in fish population, near the Portelo mines. The low ecological integrity status detected in the lotic ecosystems in NE Portugal as a result of mineral and organic pollution deserves the development of several measures for rehabilitation and improving of water quality. On the other hand, environmental education actions are needed to contribute to improvement of ecological integrity of the river and its conservation.

Does spatial distribution of fauna depend on algal belts on intertidal boulder fields of the French Basque coast ?

To determine good ecological status and conservation of the Sub-Marine area of the Bay of Biscay, the implementation of a new rocky intertidal habitats monitoring is needed. A protocol has been adapted from the Brittany protocol for the water body FRFC11 "Basque coast" for the two indicators "intertidal macroalgae" and "subtidal macroalgae" under the Water Framework Directive to qualify the ecological. However no protocol has been validated for fauna in front of meridional characters of the benthic communities. Investigations carried out on macroalgae communities on intertidal area in WFD framework, since 2008, constitute an important working basis. This is the aim of the Bigorno project (Intertidal Biodiversity of the south of the Bay of Biscay and Observation for New search and Monitoring for decision support), financed by the Agency of Marine Protected Areas and the Departmental Council. To implement knowledge, a sampling protocol has been used in 2015 on the boulder fields of Guéthary. This site is part of Natura 2000 area "rocky Basque coast and offshore extension "It constitutes also a Znieff site and restricted fishing area. The sampling strategy considers the heterogeneity of substrates and the presence of intertidal microhabitats. Two main habitats are present: "mediolittoral rock in exposed area habitat" and "boulder fields". Habitat "intertidal pools and permanent ponds" is also present but, it is not investigated. Sampling effort is of 353 quadrats of 0.1 m², drawn randomly according to a spatially stratified sampling plan, defined by habitat and algal belts. Taxa identification and enumeration are done on each quadrat. The objective of this work is to expose results from data collected during 2015 sampling program. The importance of characterizing benthic fauna communities spatial distribution belonging to the Basque coast according to algal belts defines during the WDF survey was highlighted. Concurrently, indicators of biodiversity were studied.

Indicator species of intertidal boulder fields on the French Basque coast

The rocky Basque coast presents an interest both in terms of biogeography and its patrimonial situation, alongside its habitats, fauna and flora. The aim of the BIGORNO project (Intertidal Biodiversity of the south of the Bay of Biscay and Observation for New research and Monitoring for decision support), financed by the Agency of Marine Protected Areas (AAMP) and the Departmental Council (CD 64), is to respond to significant deficiencies on biocenosis in the southern marine subregion “Bay of Biscay”. Investigations carried out in the WFD, since 2008, constitute an important basis of work for integration of fauna. Field studies undertaken since 2015 consisting of a sampling design suited to the substrates heterogeneity and the presence of microhabitats were established on an intertidal area specifically on a "Boulder fields" habitat. Assessment was undertaken by sampling quadrats of 0.1 m² drawn randomly from a spatially stratified sampling plan. Our study aims for a better understanding of stratification of this habitat and allowed us to highligh tindicator taxa of the "Boulder fields" habitat. Functions included in the package indicspecies (CRAN) were used to conduct indicator species analysis and to assess the significance of the relationship between taxa or taxa combinations and the habitat. It is therefore possible to describe some species or species groups which are specific to boulder fields through the assessment of their functional traits and local biodiversity. These various analyses allow for a sustainable way of monitoring the Basque intertidal rocky shore.