The potential of using the Ecosystem Approach in the implementation of the EU Water Framework Directive

Incorporating Ecosystem Services into Water Resources Management-Tools, Policies, Promising Pathways

Ecosystems provide a range of services, including water purification, erosion prevention, and flood risk mitigation, that are important to water resource managers. But as a sector, water resources management has been slow to incorporate ecosystem protection and restoration, for a variety of reasons, although related concepts such as nature-based solutions and green infrastructure are gaining traction. We explain some of the existing challenges to wider uptake of the ecosystem services concept in water resources management and introduce some promising avenues for research and practice, elaborated in more detail through 12 papers, spanning five continents and a variety of contexts, which make up a Special Issue on "Incorporating Ecosystem Services into Water Resources Management". Cross-cutting themes include (A) ecosystem services as a flexible concept to communicate with stakeholders; (B) participatory processes to involve stakeholders in research; (C) multiple values, and valuation methods, of water-related services; and (D) applications of decision-support tools. We conclude with a summary of research gaps and emphasize the importance of co-producing knowledge with decision makers and other stakeholders, in order to improve water resources management through the integration of ecosystem services.

River and lake nutrient targets that support ecological status: European scale gap analysis and strategies for the implementation of the Water Framework Directive

Eutrophication caused by an excessive presence of nutrients is affecting large portions of European waters with more than 60% of the surface water bodies failing to achieve the primary ambition of water management in Europe, that of good ecological status (GES) with diffuse emission from agriculture being the second most important pressure affecting surface waters. We developed EU wide and regional nutrient targets that define the boundary concentrations between good and moderate status for river and lake total P (TP) and total N (TN) and assessed the gap between actual nutrient concentrations and these targets and considered strategies of nutrient reductions necessary to achieve GES and deliver ecosystem services. The nutrient targets established for rivers ranged from 0.5-3.5 mg/L TN and 11-105 μg/L TP and for lakes 0.5-1.8 mg/L TN and 10-60 μg/L TP. Based on the EU wide targets, 59% of the TN and 57% of the TP river monitoring sites and 64% of the TN and 61% of the TP lake monitoring sites exceed these value and are thus at less than GES. The PCA and step-wise regression for EU basins clearly showed that the basin nutrient export is predominantly related to agricultural inputs. In addition, the step-wise regression models for TN and TP provided the ability to extrapolate the results and quantify the input reductions necessary for reaching the nutrient targets at the EU level. The results suggest that a dual water management strategy would be beneficial and should focus a) on those less polluted rivers and lakes that can easily attain the GES goal and b) on the more highly polluted systems that will improve the delivery of ecosystem services.

Ecosystem Service Assessments within the EU Water Framework Directive: Marine Mussel Cultivation as a Controversial Measure

To combat the persistent eutrophication in coastal waters, sustainable sea-based measures are recommended. Yet, they are the subject of controversial stakeholder discussion, which hampers the implementation and planning process. The aim of this study is to evaluate if a participatory mapping (PM) approach and ecosystem service assessments (ESA) can be suitable tools within Water Framework Directive (WFD) implementation to support the communication with different target groups to improve and accelerate the planning and realization of new sea-based mitigation measures. We conducted three stakeholder-based PMs to visualize the perception of sea-based mitigation measures in coastal waters and seven different ESAs to investigate the perceptions of different mussel cultivation scenarios as mitigation measures. The PMs showed that ecological measures were preferred. The ESA approach showed that, while experts rated mussel cultivation scenarios positively overall, non-expert stakeholders still seemed skeptical and preferred alternative measures like floating wetlands. The methodological results indicate that PM can be a cost-effective tool to visualize stakeholders’ perceptions, but it needs to be applied with an ESA to be beneficial for the WFD implementation process. A web-based ESA improves the discussion with stakeholders and can reveal potential misperceptions and concerns faster and lead to a more focused discussion.

Effects of excessive water extraction on groundwater ecosystem services: Vulnerability assessments using biophysical approaches

In this research, a systematic, integrated framework was developed to evaluate the biophysical state and vulnerability intensity of groundwater supply ecosystem service (GSES) regarding excessive groundwater withdrawal in the Mashhad plain located in the northeastern of Khorasan Razavi province in Iran. At first, following an indexing approach, the biophysical aspects of the ecosystem, including capacity, flow, and the benefits of GSES, were analyzed. Afterward, the relationship between the capacity and flow ecosystem service (ES) was assessed to identify ecosystem's sustainability status. Furthermore, GSES stability was spatially shown. Finally, GSES vulnerability and its associated ESs was assessed based on 3D model of vulnerability via indexing three components of exposure, sensitivity, and adaptive capacity. The final map spatially indicated the zoning of groundwater ecosystem services' vulnerability intensity in Mashhad Plain. The outcomes indicate a high and very high vulnerability in more than 35% of studying area. The results indicate that about 18%, 30%, and 15% of studying land show moderate, low, and no vulnerability, respectively. Finally, it was observed that due to groundwater's over-extraction, supplying the aquifer ecosystem services was disrupted. This method can be used as a solution for the sustainable management of groundwater resources, especially in the arid and semi-arid countries facing the depletion of water resources.

Assessing the feasibility and value of employing an ecosystem services approach in chemical environmental risk assessment under the Water Framework Directive

The feasibility and added value of an ecosystem services approach in retrospective environmental risk assessment were evaluated using a site-specific case study in a lowland UK river. The studied water body failed to achieve good ecological status temporarily in 2018, due in part to the exceedance of the environmental quality standard (annual average EQS) for zinc. Potential ecosystem service delivery was quantified for locally prioritised ecosystem services: regulation of chemical condition; maintaining nursery populations and habitats; recreational fishing; nature watching. Quantification was based on observed and expected taxa or functional groups within WFD biological quality elements, including macrophytes, benthic macroinvertebrates and fish, and on published functional trait data for constituent taxa. Benthic macroinvertebrate taxa were identified and enumerated before, during and after zinc EQS exceedance, enabling a generic retrospective risk assessment for this biological quality element, which was found to have good ecosystem service potential. An additional targeted risk assessment for zinc was based on laboratory-based species sensitivity distributions normalised using biotic-ligand modelling to account for site-specific, bioavailability-corrected zinc exposure. Risk to ecosystem services for diatoms (microalgae) was found to be high, while risks for benthic macroinvertebrates and fish were found to be low. The status of potential ecosystem service delivery (ESD) by fish was equivalent to high ecological status defined under the WFD, while ESD was higher for benthic macroinvertebrates than defined by WFD methods. The illustrated ecosystem services approach uses readily available data and adds significantly to the taxonomic approach currently used under the WFD by using functional traits to evaluate services that are prioritised as being important in water bodies. The main shortcomings of the illustrated approach were lack of: representation of bacteria and fungi; WFD predicted species lists for diatoms and macrophytes; site-specific functional trait data required for defining actual (rather than potential) ecosystem service delivery.

Incorporating Ecosystem Services in the Assessment of Water Framework Directive Programmes of Measures

The EU Water Framework Directive requires the development of management responses aimed towards improving water quality as a result of improving ecosystem health (system state). Ecosystems have potential to supply a range of services that are of fundamental importance to human well-being, health, livelihoods and survival, and their capacity to supply these services depends on the ecosystem condition (its structure and processes). According to the WFD, Programmes of Measures should be developed to improve overall water status by reducing anthropogenic catchment pressures to levels compatible with the achievement of the ecological objectives of the directive, and when designed and implemented properly should improve the ecological condition of aquatic ecosystems that the delivery of ecosystem services depends on. Monitoring and evaluation of implemented measures are crucial for assessing their effectiveness and creating the agenda for consecutive planning cycles. Considering the challenges of achieving water status improvements, and the difficulties of communicating these to the wider public, we develop a framework for the evaluation of measures cost-effectiveness that considers ecosystem services as the benefits from the reduction of pressures on water bodies. We demonstrate its application through a case study and discuss its potential to facilitate the economic analysis required by the directive, and that most European water authorities had problems with. Findings demonstrate the potential of the methodology to effectively incorporate ecosystem services in the assessment of costs and benefits of proposed actions, as well as its potential to engage stakeholders.

Assessing the hydrogeological resilience of a groundwater-dependent Mediterranean peatland: Impact of global change and role of water management strategies

Mediterranean peatlands remain largely under-documented, except for detailed biological data such as fauna and flora taxa lists, and yet are increasingly threatened by water withdrawal and agriculture practices. This lack of information, particularly on their hydrogeological functioning, makes it impossible to evaluate their response to changing climate conditions. A pilot study on a representative Mediterranean peatland on the island of Corsica (France) was conducted to evaluate recharge modalities in the peatland using a coupled water-level monitoring, geochemical and isotope multi-tracing approach (electric conductivity, major ions, δ¹⁸O, δ²H, ³H, ⁸⁷Sr/⁸⁶Sr). The goal was to understand how water budgets in peatland ecosystems were maintained throughout the year, especially during the summer. Despite the remarkable stability of the peatland water level, the recharge contributions of varied water bodies through an alluvial aquifer vary significantly from one season to another. An end-member mixing analysis (EMMA) indicates that the peatland is mainly recharged by an alluvial aquifer. During fall-winter, the alluvial aquifer on which the peatland depends is recharged by the rainfall, a river, and shallow groundwater (colluvium). During spring-summer, water supply is provided mostly by a river, shallow, and deep groundwater (fractured granite). However, this specific hydrogeological functioning is not taken into account by environmental management policies making peatlands vulnerable to anthropogenic and climatic pressures. Thus, their actual status regarding water and aquatic environment management policies is discussed to provide recommendations for better consideration and preservation.

Filling the Gap between Ecosystem Services Concept and River Basin Management Plans: The Case of Greece in WFD 20+

The ecosystem services (ES) concept is embedded in all new European directives but its integration in the Water Framework Directive (WFD) is absent, despite the latter being the major legislative tool. The research aims to assess the knowledge of ES that lies within the River Basin Management Plans (RBMPs) in Greece so as to further depict their representation in the relevant planning tools, to support policy making and express the implementation experience to Member States for assisting EU reloading processes. The information on the ES’ status was extracted by the official RBMPs, processed and grouped following Common International Classification of Ecosystem Services (CICES) classification. The prioritization of ES included in the programs of measures (PoMs) further showed the targeting for each River Basin District (RBD). The results were not homogenous for the RBDs, revealing different needs in measures and indicating there is a lack in “communication” between the relevant EU and national regulations. Moreover, a wide suite of water-related ES is hindered in addressing multiple benefits coming from provisioning, regulating and cultural ES. For a proper WFD reload and continuation, the infusion of the ES concept and prerequisites in its objective, and the reviewing of the RBMPs’ target and the suggestion of integrated PoMs are necessary steps that could deliver added value in such legislation.

Valuing inland blue space: A contingent valuation study of two large freshwater lakes

Water bodies, or blue spaces, offer a range of health and well-being benefits. Many of these benefits occur in waterside spaces and do not require direct water contact. For example, non-water based physical activity (e.g. walking and running) and reduced stress as a result of viewing water from a distance. However, research dedicated to understanding the economic impact of changes to freshwater ecosystems predominantly focuses on water-based recreation and water quality. As a result, the economic impacts of changes to waterside space are often overlooked. This study used the contingent valuation method to determine public preference for the protection of lakeside quality, in terms of lake views, path quality and lakeside access, at two large freshwater lakes in Scotland (Loch Lomond and Loch Leven). The aim of the study was to estimate willingness to pay among a sample of adults in Scotland (n = 1056) for the protection of lakeside quality. Results indicate that the majority of respondents are willing to pay for the preservation of lakeside quality at each lake. Based upon the most conservative estimates obtained, mean willingness to pay for the protection of lakeside quality was £12.06 per household per year at Loch Lomond and £8.44 at Loch Leven. These findings provide valuable economic data and suggest that changes to waterside space at destination water bodies have nationally important economic impacts. Greater consideration of the economic impact of changes to lakeside space is recommended in order to develop cost-effective and socially optimal water resource management policies at large freshwater lakes.

Assessing environmental impacts of large centralized wastewater treatment plants with combined or separate sewer systems in dry/wet seasons by using LCA

Rainfall can affect influent flow rate and compositions of wastewater, and thus further affect wastewater treatment performance and the effluent quality. This study aims to study the influence of rainfall on the environmental impacts of centralized wastewater treatment plants. The correlations between rainfall, and influent flow rate and compositions of wastewater in wet and dry seasons with two sewer systems, i.e. combined and separate sewer systems, were primarily established. Environmental impacts were assessed with life cycle assessment (LCA) to understand the temporal environmental burdens in wet and dry seasons. Functional units as per m3 treated wastewater (FU1) and as per kg PO43-eq. removed (FU2), respectively, were used to evaluate impacts of wastewater treatment to the environment. Strong correlation between rainfall and the influent flow rate was found in the wastewater treatment plants with either a combined sewer system (with Pearson correlation coefficient r at 0.66) or a separate sewer system (with r at 0.84), where r represents the strength of the association between two variables. The rainfall effect is more obvious on the eutrophication potential and global warming potential than on other environmental indicators while sewer system, i.e. combined or separate, seems not important in the two cases studied. Both wastewater treatment plants (WWTPs) show a lower environmental burden in the wet season than in the dry season partially due to the dilution of wastewater by using FU1. The WWTP receiving high strength wastewater, however, demonstrates higher environmental impacts in the wet season by using FU2 than FU1, due to the less efficient treatment caused by heavy rainfall. Meanwhile, it is found that environmental impacts from the WWTP receiving low strength wastewater have no difference when using either FU1 or FU2. The results indicate that the environmental burdens particularly eutrophication and global warming caused by WWTPs are dependent on the correlations of rainfall intensity with wastewater quantity and quality instead of combined or separate sewer system. This could be used to guide a stricter control of eutrophication in a more sensitive season in more vulnerable receiving waters.

Making the ecosystem services approach operational: A case study application to the Aarhus River, Denmark

The ecosystem services (ESS) approach seeks to identify and characterize links between ecosystems and human welfare. The DESSIN ESS evaluation framework is a novel methodology that has been developed to operationalize ecosystem service assessment, with a focus on urban freshwater settings. This paper describes an application of the framework to a retrospective case study in Aarhus, Denmark, which was used to test the framework and make suggestions for improvement. River restoration and wastewater management measures enhanced ecosystem state and the provision and use of purification and recreation ESS for selected beneficiaries, including increased economic values. Feedback from this case study suggests a missing link between science-based ESS approaches, which often have a normative basis in ecosystem status, and the real-world provision and use of ESS in urban settings. In the urban context, many ESS result from a combination of human and ecosystem inputs, and the human inputs can often be significant. Quantifying ESS provision and use therefore requires understanding how ecosystem and human inputs work together to make contributions to human welfare.

Hidden treasures: Human-made aquatic ecosystems harbour unexplored opportunities

Artificial water bodies like ditches, fish ponds, weirs, reservoirs, fish ladders, and irrigation channels are usually constructed and managed to optimize their intended purposes. However, human-made aquatic systems also have unintended consequences on ecosystem services and biogeochemical cycles. Knowledge about their functioning and possible additional ecosystem services is poor, especially compared to natural ecosystems. A GIS analysis indicates that currently only ~ 10% of European surface waters are covered by the European Water Framework directive, and that a considerable fraction of the excluded systems are likely human-made aquatic systems. There is a clear mismatch between the high possible significance of human-made water bodies and their low representation in scientific research and policy. We propose a research agenda to build an inventory of human-made aquatic ecosystems, support and advance research to further our understanding of the role of these systems in local and global biogeochemical cycles as well as to identify other benefits for society. We stress the need for studies that aim to optimize management of human-made aquatic systems considering all their functions and to support programs designed to overcome barriers of the adoption of optimized management strategies.

Implementation of the Water Framework Directive: Lessons Learned and Future Perspectives for an Ecologically Meaningful Classification Based on Phytoplankton of the Status of Greek Lakes, Mediterranean Region

The enactment of the Water Framework Directive (WFD) initiated scientific efforts to develop reliable methods for comparing prevailing lake conditions against reference (or nonimpaired) states, using the state of a set biological elements. Drawing a distinction between impaired and natural conditions can be a challenging exercise. Another important aspect is to ensure that water quality assessment is comparable among the different Member States. In this context, the present paper offers a constructive critique of the practices followed during the WFD implementation in Greece by pinpointing methodological weaknesses and knowledge gaps that undermine our ability to classify the ecological quality of Greek lakes. One of the pillars of WDF is a valid lake typology that sets ecological standards transcending geographic regions and national boundaries. The national typology of Greek lakes has failed to take into account essential components. WFD compliance assessments based on the descriptions of phytoplankton communities are oversimplified and as such should be revisited. Exclusion of most chroococcal species from the analysis of cyanobacteria biovolume in Greek lakes/reservoirs and most reservoirs in Spain, Portugal, and Cyprus is not consistent with the distribution of those taxa in lakes. Similarly, the total biovolume reference values and the indices used in classification schemes reflect misunderstandings of WFD core principles. This hampers the comparability of ecological status across Europe and leads to quality standards that are too relaxed to provide an efficient target for the protection of Greek/transboundary lakes such as the ancient Lake Megali Prespa.

Using a systemic approach to address the requirement for Integrated Water Resource Management within the Water Framework Directive

Sustainable management of water resources calls for integration of ideas and approaches and revolves around assessment of causal-effect relationships as tools towards defining informed mitigation options and planning. The current paper presents a new holistic approach developed within the Globaqua Coordination Project that combines indicator-based well-established and tested concepts towards developing informed Programmes of Measures and River basin management plans: a. The DPSIR framework that has been engaged as central instrument to address the Water Framework Directive requirements and the concepts embedded in the Integrated Water Resource Management; b. The Ecosystem Services Approach emphasizing on the links between ecosystem services, changes in ecosystems and human well-being, c. Scenario assessment for valuation of future conditions to ensure the sustainability in the use of water resources. The implementation of the new combined framework in two river basins, Ebro in Spain and Evrotas in Greece, stressed the need for revised options targeting elimination of water pollution, measures to ensure water supply that covers the demand even under conditions of climate change and increased water stress and the need for improved valuation of environmental and resource use costs.

Chemical mixtures and fluorescence in situ hybridization analysis of natural microbial community in the Tiber river

The Water Framework Directive (WFD) regulates freshwater and coastal water quality assessment in Europe. Chemical and ecological water quality status is based on measurements of chemical pollutants in water and biota together with other indicators such as temperature, nutrients, species compositions (phytoplankton, microalgae, benthos and fish) and hydromorphological conditions. However, in the current strategy a link between the chemical and the ecological status is missing. In the present WFD, no microbiological indicators are foreseen for integrating the different anthropogenic pressures, including mixtures of chemicals, nutrients and temperature changes, to provide a holistic view of the freshwater ecosystem water quality. The main aim of this work was to evaluate if natural microbial populations can be valuable indicators of multiple stressors (e.g. chemical pollutants, temperature, nutrients etc.) to guide preventive and remediation actions by water authorities. A preliminary survey was conducted to identify four sites reflecting a contamination gradient from the source to the mouth of a river suitable to the objectives of the European Marie Curie project, MicroCoKit. The River Tiber (Italy) was selected as a pilot case study to investigate the correlation between bacteria taxa and the chemical status of the river. The main physicochemical parameters, inorganic elements, organic pollutants and natural microbial community composition were assessed at four selected sites corresponding to pristine, agricultural, industrial and urban areas for three consecutive years. The overall chemical results indicated a correspondence between different groups of contaminants and the main contamination sources at the selected sampling points. Phylogenetic analysis of the microbial community analyzed by Fluorescence In Situ Hybridization method (FISH) revealed differences among the four sampling sites which could reflect an adaptive bacterial response to the different anthropogenic pressures.

Relationship between ecological condition and ecosystem services in European rivers, lakes and coastal waters

We quantify main ecosystem services (i.e. the contribution of ecosystems to human well-being) provided by rivers, lakes, coastal waters and connected ecosystems (riparian areas and floodplains) in Europe, including water provisioning, water purification, erosion prevention, flood protection, coastal protection, and recreation. We show European maps of ecosystem service capacity, flow (actual use), sustainability and efficiency. Then we explore the relationship between the services and the ecosystem condition at the European scale, considering the ecological status of aquatic ecosystems, reported under the EU Water Framework Directive, as a measure of the ecosystem integrity and biodiversity. Our results indicate that a higher delivery of the regulating and cultural ecosystem services analysed is mostly correlated with better conditions of aquatic ecosystems. Conversely, the use of provisioning services can result in pressures on the ecosystem. This suggests the importance of maintaining good ecological condition of aquatic ecosystems to ensure the delivery of ecosystem services in the future. These results at the continental scale, although limited to the ecosystem services under analysis, might be relevant to consider when investing in the protection and restoration of aquatic ecosystems called for by the current EU water policy and Biodiversity Strategy and by the United Nations Sustainable Development Goals.

Water Framework Directive programmes of measures: Lessons from the 1st planning cycle of a catchment in England

The European Union's Water Framework Directive (WFD) required Member States to establish programmes of measures to achieve good water status formally by 2015, but on postponing the deadline by two six-year periods, by 2027 at the latest. With many Member States facing problems with developing such measures in the first planning cycle, and limited change in ecological status since the first river basin management plans were reported, we look at the implementation of the Directive in England, where only 17% of the surface water bodies were found at good status in 2015, a reduction of 4% since 2009. Using as a case study the Broadland Rivers catchment, we examine the measures taken for Cycle 1 and changes in the classifications of water body status, to investigate whether the way the measures were developed could have limited their potential to deliver WFD objectives. While the WFD was adopted to succeed and replace management practices targeting individually non-compliant element, findings indicate that little had changed in the way measures were developed. Although considerable progress has been made on the implementation of these measures, the limited progress in improving classifications demonstrates the limits of this approach and further makes the case for what the WFD was introduced for: the harmonised transposition of the Integrated River Basin Management paradigm, as the key for delivering good ecological status.

Assessing Changes in Ecosystem Services Provision in Coastal Waters

Coastal ecosystems are important ecosystem services (ES) suppliers. The degradation of these ecosystems jeopardizes the quality of ES provision. The Biodiversity 2020 Strategy aims at maintaining and restoring ES, although clear guidelines are missing on how to define the state to which ES should be restored. In this respect, synergies between ES assessments and the Water Framework Directive (WFD) exist, but methodological approaches to connect both are lacking. The Marine Ecosystem Services Assessment Tool (MESAT) can overcome this problem. In this study, the tool is applied to semi-open and open coastal water bodies in the Southern Baltic Sea, the Greifswald Bay and Pomeranian Bay. The resulting changes in ES provision confirm the ability of MESAT to be applied in all WFD water body types and a multitude of environmental and anthropogenic gradients. Nevertheless, problems such as data scarcity, spatial extent and historical background of the case studies require adaptations in the assessment process. The spatial extent of all case studies allowed to cover a connected system with a strong environmental (salinity) gradient. Analyzing changes in ES provision in connected systems can help to better understand linkages between ES provision and environmental and anthropogenic stressors as well as trade-offs between ES across water bodies. This information can be further used to support the design of management plans. From the analysis of all MESAT case studies, major factors were identified for the tool to be transfered into a European context, as well as potential problems and solutions. Following the WFD is a strong advantage, which ensures the tool’s transferability to other areas.

Protecting and restoring Europe's waters: An analysis of the future development needs of the Water Framework Directive

The Water Framework Directive (WFD) is a pioneering piece of legislation that aims to protect and enhance aquatic ecosystems and promote sustainable water use across Europe. There is growing concern that the objective of good status, or higher, in all EU waters by 2027 is a long way from being achieved in many countries. Through questionnaire analysis of almost 100 experts, we provide recommendations to enhance WFD monitoring and assessment systems, improve programmes of measures and further integrate with other sectoral policies. Our analysis highlights that there is great potential to enhance assessment schemes through strategic design of monitoring networks and innovation, such as earth observation. New diagnostic tools that use existing WFD monitoring data, but incorporate novel statistical and trait-based approaches could be used more widely to diagnose the cause of deterioration under conditions of multiple pressures and deliver a hierarchy of solutions for more evidence-driven decisions in river basin management. There is also a growing recognition that measures undertaken in river basin management should deliver multiple benefits across sectors, such as reduced flood risk, and there needs to be robust demonstration studies that evaluate these. Continued efforts in 'mainstreaming' water policy into other policy sectors is clearly needed to deliver wider success with WFD goals, particularly with agricultural policy. Other key policy areas where a need for stronger integration with water policy was recognised included urban planning (waste water treatment), flooding, climate and energy (hydropower). Having a deadline for attaining the policy objective of good status is important, but even more essential is to have a permanent framework for river basin management that addresses the delays in implementation of measures. This requires a long-term perspective, far beyond the current deadline of 2027.

Priorities and opportunities in the application of the ecosystem services concept in risk assessment for chemicals in the environment

The ecosystem services approach has gained broad interest in regulatory and policy circles for use in ecological risk assessment. Whilst identifying several challenges, scientific experts from European regulatory authorities, the chemical industry and academia considered the approach applicable to all chemical sectors and potentially contributing to greater ecological relevance for setting and assessing environmental protection goals compared to current European regulatory frameworks for chemicals. These challenges were addressed in workshops to develop a common understanding across stakeholders on how the ecosystem services concept might be used in chemical risk assessment and what would need to be done to implement it. This paper describes the consensus outcome of those discussions. Knowledge gaps and research needs were identified and prioritised, exploring the use of novel approaches from ecology, ecotoxicology and ecological modelling. Where applicable, distinction is made between prospective and retrospective ecological risk assessment. For prospective risk assessment the development of environmental scenarios accounting for chemical exposure and ecological conditions was designated as a top priority. For retrospective risk assessment the top priority research need was development of reference conditions for key ecosystem services and guidance for their derivation. Both prospective and retrospective risk assessment would benefit from guidance on the taxa and measurement endpoints relevant to specific ecosystem services and from improved understanding of the relationships between measurement endpoints from standard toxicity tests and the ecosystem services of interest (i.e. assessment endpoints). The development of mechanistic models, which could serve as ecological production functions, was identified as a priority. A conceptual framework for future chemical risk assessment based on an ecosystem services approach is presented.

Trace elements: critical insights from 15 years of monitoring in the Venice Lagoon catchment basin (Italy)

The study focused on selected trace elements (As, Cd, Cr, Hg, Ni, Pb) monitored in surface waters of the Venice Lagoon catchment basin (North East Italy) over the period 2000-2015. The monitoring was undertaken to verify the achievement of the quality objectives set by the European and national legislations. The available results have been analyzed to evaluate the chemical status of water bodies. The limit of quantification (LOQ) of the applied analytic techniques appears critical for the adequate water monitoring; for some parameters, the percentage of not visible values due to non-satisfactory LOQ was higher in the beginning of the period; the subsequent improvement of LOQ allowed assessing the respect of environmental quality standards (EQSs). The study analyzes time trends in single stations and the differences between detected concentrations in the considered stations. Moreover, maximum concentrations and water flows have been considered to understand the potential correlation. Cumulated frequency curves for the most critical parameters have been built to identify situation of potential overtaking of the EQSs in force. The most polluted sampling stations of the drainage basin for the six trace elements were found in Cuori and Fiumazzo rivers. Although LOQs changed over time, the recorded trends show a quality improvement and a good compliance with respect to EQSs set by European legislation, while considering EQSs set by local special legislation, the objectives are not yet satisfied. Arsenic is ubiquitous; thus, it can be supposed to be originated as a background environmental concentration, while nickel appears of industrial origin according to its point and local presence.

Estimation of benefits from the actual use of inland water ecosystem services in the Slovak Republic

The primary aim of the article is to obtain an overview of benefits from the actual use of inland water ecosystem services (ESSs) in Slovakia. The evaluation, which includes both surface water and groundwater, is primarily focused on demand side. Methods for assessing the benefits of the most prevalent ESSs, designated by Common International Classification of Ecosystem Services (CICES classification) v. 4.3, are described and discussed. The evaluation is performed at the level of 10 sub-basins to which available data are allocated. In the absence of necessary data or the impossibility of allocating them to sub-basins, the benefit from the use of some ESSs is estimated at the level of whole Slovak territory. The use of ESSs valuation in practice, especially with regard to water protection of surface water and groundwater, is discussed. The evaluation of benefits from ESSs of inland waters in Slovakia so far does not allow direct use of obtained results for proposal of measures within river basin management plans as suggested by several authors. Main reason is the input data availability and quality. At the present time, the significance of the ESSs evaluation may rather lie in the awareness of the value that human society gains from the use of inland waters. It becomes more evident that increase in environmental awareness alone is not sufficient in terms of the protection of ecosystems and their services. To achieve unambiguous and lasting improvement in this area, it is necessary to address the deeper causes, closely related to human thinking and behaviour.

Reasserting the primacy of human needs to reclaim the 'lost half' of sustainable development

The concept of sustainable development evolved from growing awareness of the interdependence of social and economic progress with the limits of the supporting natural environment, becoming progressively integrated into global agreements and transposition into local regulatory and implementation frameworks. We argue that transposition of the concept into regulation and supporting tools reduced the focus to minimal environmental and social standards, perceived as imposing constraints rather than opportunities for innovation to meet human needs. The aspirational 'half' of the concept of sustainable development specifically addressing human needs was thus lost in transposing high ideals into regulatory instruments. The Sustainable Development Goals (SDGs) restore focus on interlinked human needs, stimulating innovation of products and processes to satisfy them. Through three case studies - PVC water pipes, river quality management in England, and UK local air quality management - we explore the current operationalisation of the concept in diverse settings, using the SDG framework to highlight the broader societal purposes central to sustainable development. Partnerships involving civil society support evolution of regulatory instruments and their implementation, optimising social and ecological benefits thereby serving more human needs. Restoring the visionary 'lost half' of sustainable development - meeting human needs in sustainable ways - creates incentives for innovation and partnership; an innovation framework rather than a perceived constraint.

Interactive effects of water quality, physical habitat, and watershed anthropogenic activities on stream ecosystem health

Ecological degradation of streams remains a major environmental concern worldwide. While stream restoration has received considerable attention, mitigation efforts focused on the improvement of physical habitat have not proven completely effective. Several small-scale studies have emphasized that effective restoration strategies require a more holistic understanding of the variables at play, although the generalization of the findings based on the small-scale studies remains unclear. Using a comprehensive statewide stream monitoring database from West Virginia (WV), a detailed landscape dataset, and a machine learning algorithm, this study explores the interactive impacts of water quality and physical habitat on stream ecosystem health as indicated by benthic macroinvertebrate scores. Given the long history of energy extraction in this region (i.e., coal mining and oil/gas production), investigation of energy extraction influences is highlighted. Our results demonstrate that a combination of good habitat and low specific conductance is generally associated with favorable benthic macroinvertebrate scores, whereas poor habitat combined with water quality conditions typically indicative of high ionic strength are associated with impaired stream status. In addition, streams impacted by both energy extraction and residential development had a higher percentage of impairment compared to those impacted predominantly by energy extraction or residential development alone. While water quality played a more important role in the ecosystem health of streams impacted primarily by energy extraction activities, habitat seems to be more influential in streams impacted by residential development. Together, these findings emphasize that stream restoration strategies should consider interactive effects of multiple environmental stressors tailored to specific sites or site types - as opposed to considering a single stressor or multiple stressors separately.

Protecting aquatic biodiversity in Europe: How much do EU environmental policies support ecosystem-based management?

The sustainable management of aquatic ecosystems requires better coordination between policies span-ning freshwater, coastal and marine environments. Ecosystem-based management (EBM) has been promoted as a holistic and integrative approach for the safekeeping and protection of aquatic biodiversity. The paper assesses the degree to which key European environmental policies for the aquatic environment, namely the Birds and Habitats Directives, Water Framework Directive and Marine Strategy Framework Directive, individually support EBM and can work synergistically to implement EBM. This assessment is based on a review of legal texts, EU guidance and implementation documents. The paper concludes that EBM can be made operational by implementing these key environmental directives. Opportunities for improving the integration of EU environmental policies are highlighted.

Outcomes of the hydromorphology integration in the Water Framework Directive: A review based on science mapping

The goal of our review was to evaluate scientific outcomes connected to hydromorphology and Water Framework Directive by synthesizing the main themes based on keywords, research domains, and the spatial coverage of high visibility publications. These data were integrated into a social network analysis to understand the structure of science related to our topic. Thus, we investigated 183 articles and conference proceedings from the Web of Science Core Collection. Among the 505 authors keywords, the central ones in our network were Water Framework Directive, hydromorphology, macroinvertebrates, ecological status, water quality, reference conditions, and river. The characteristics of the network of keywords indicated that information developed around a few key-concepts linked to numerous peripheral keywords, which highlighted some main themes of research. Hydromorphology appeared mostly in articles with macroinvertebrates and river restoration, suggesting the acceptance of environmental-based paradigm in water bodies' management. Consequently, we expected to count the majority of publications in Environmental Sciences & Ecology research domain. Issues related to the society (e.g. public participation, stakeholders) didn't appear in our analysis. Publications covered especially European Union member states, the network being dominated by Germany, Italy, and UK in terms of both study area and authorship. Besides traditional scientific relations between Western and Northern European states, we also noticed numerous comparisons between Danube countries. To comment the position of these publications in the scientific world, we used the Article Influence Score, which was below the average for the main research domain of Environmental Sciences & Ecology, probably as a consequence of the regional cover and concern of the Water Framework Directive. Further, we recommend more connections between environmental and social sciences, as well as between countries and we encourage funding for open access publications in order to increase the visibility and influence of the topic of hydromorphology and Water Framework Directive both bibliometrically and for decision and policy makers.

Assessing watercourse quality: challenges in implementing European and Swiss legal frameworks

Hydro-climatic changes and the increasing release of pollutants into rivers by human activities tend to affect the quality of watercourses, to alter aquatic ecosystems and to reduce the amount of useable water. The ecological and chemical states of rivers and their evolution is thus of growing concern. In Europe and Switzerland, water policies are progressively shifting towards a holistic approach of river systems. The European Commission notably established a framework to highlight rivers' ecological deficits and to enhance regional or local water management plans. In Switzerland, a similar framework is currently under development. In this paper, both procedures are compared and implemented in a Swiss catchment dominated by agricultural activities. The aim is to define the challenges that still need to be addressed to assess and sustain river health. The hydromorphological, ecological, and ecotoxicological quality of the river was evaluated. Both frameworks highlighted the fact that no section of the river can currently be classified as being in a good environmental state and that the state deteriorates as tributaries and wastewater discharge flow into the main riverbed. Chemical issues and water quality changes due to hydro-climatic variations and management strategies were also pinpointed. Both frameworks are thus useful tools to survey changes in rivers quality in space and over time. However, challenges remain regarding the appropriate strategies to monitor and analyze chemicals, the definition of target values and conditions, the evaluation and integration of human-induced pressures, and the overall evaluation of the state of a river. The development of integrated indicators or of ecosystem services approaches is considered as a potential solution to explore river health and to define efficient restoration measures by water managers.

Using a multi-criteria analysis to identify rivers with hydromorphological restoration priority: Braided rivers in the south-eastern Subcarpathians (Romania)

In order to systematically plan river restoration actions at a regional scale, this paper develops a multi-criteria analysis that classifies rivers, based on their priority for hydromorphological restoration. This priority is defined by severe human pressures within the erodible corridor of the river, drastic alteration of the stream channel, and low intensity of river pattern functioning. Based on relevant indicators for three groups of features (human pressures, channel changes, and river functionality), a Hydromorphological Restoration Priority Index (HRPI) was designed. The high values (>66%) of HRPI reflect an urgent need for hydromorphological restoration while low values (<33%) reveal a less immediate necessity for restoration. The proposed methodology was applied on braided sectors of rivers crossing the south-eastern (Curvature) Subcarpathians (Romania). The values of the total HRPI ranged between 21% (Zăbrăuţ River) and almost 44% (Prahova River). According to our results, most of the analyzed sectors have a low need for hydromorphological restoration of the braided pattern, while some have a moderate necessity for restoration. Whereas the Prahova River has the highest HRPI, it should be given priority for restoration at a regional scale, which corresponds to the objectives of River Basin Management Plans for the interval beyond 2021.

Assessment of water retention function as tool to improve integrated watershed management (case study of Poprad river basin, Slovakia)

The presented study concentrates on assessing the ecosystem function of water retention. The water retention function is defined as the ability of the landscape to retain water, slow runoff and encourage water infiltration. The water retention function was expressed by calculating the hydric significance (HS) indicator. This method is based on scoring the individual input parameters according to their overall impact on watershed hydrology. The study was conducted on a sample area of Poprad River basin. The final results presented a spatial distribution of hydric function within the watershed classified according to its significance into four classes (from limited to excellent significance). A breakdown of the results on the level of elementary watersheds was used in order to examine those with low hydric function. The results showed a significant influence of land-use on retention function; however, this impact could be limited by extreme precipitation or high soil water saturation. The methodology of hydric significance represents an innovative approach towards assessment of ecosystem function of water retention on regional level.

The EU Water Framework Directive: From great expectations to problems with implementation

The Water Framework Directive 2000/60/EC (WFD) is widely accepted as the most substantial and ambitious piece of European environmental legislation to date. It has been referred to as a once in a generation opportunity to restore Europe's waters and a potential template for future environmental regulations. However, fifteen years since it was adopted, and with many problems and delays in its implementation, the WFD has not delivered its main objectives of non-deterioration of water status and the achievement of good status for all EU waters. Putting aside the daunting technical and organisational challenges of its implementation, this paper aims to shed light on why the great expectations that came with the WFD have not yet been fully realised. It reviews how the Directive has been interpreted, focusing on its intentions and how they were applied. The findings reveal the absence of the paradigm shift towards the systems (integrated) thinking that the WFD was grounded on, as a fundamental problem with its implementation. This is also evident in cases where the Directive has been criticised as a policy tool or when implementation efforts were reviewed, indicating misunderstandings even of its core principles. This inherent departure from the Directive's systemic intention and methodological approach needs further investigation, as it could be the reason behind many of its problems and delays. Unless current implementation efforts are reviewed or revised in light of this, enabling the paradigm shift required to ensure a more sustainable and holistic approach to water management, the fading aspirations of the initial great expectations that came with the Directive could disappear for good.

Placing ecosystem services at the heart of urban water systems management

Current approaches have failed to deliver a truly integrated management of the different elements of the urban water system, such as freshwater ecosystems, drinking water treatment plants, distribution networks, sewer systems and wastewater treatment plants. Because the different parts of urban water have not been well integrated, poor decisions have been made for society in general, leading to the misuse of water resources, the degradation of freshwater ecosystems and increased overall treatment costs. Some attempts to solve environmental issues have adopted the ecosystem services concept in a more integrated approach, however this has rarely strayed far away from pure policy, and has made little impact in on-the-ground operational matters. Here, we present an improved decision-making framework to integrate the management of urban water systems. This framework uses the ecosystem service concept in a practical way to make a better use of both financial and water resources, while continuing to preserve the environment.

Coupling systematic planning and expert judgement enhances the efficiency of river restoration

Ineffectiveness of current river restoration practices hinders the achievement of ecological quality targets set by country-specific regulations. Recent advances in river restoration help planning efforts more systematically to reach ecological targets at the least costs. However, such approaches are often desktop-based and overlook real-world constraints. We argue that combining two techniques commonly used in the conservation arena - expert judgement and systematic planning - will deliver cost-effective restoration plans with a high potential for implementation. We tested this idea targeting the restoration of spawning habitat, i.e. gravel bars, for 11 rheophilic fish species along a river system in Germany (Havel-Spree rivers). With a group of local fish experts, we identified the location and extent of potential gravel bars along the rivers and necessary improvements to migration barriers to ensure fish passage. Restoration cost of each gravel bar included the cost of the action itself plus a fraction of the cost necessary to ensure longitudinal connectivity by upgrading or building fish passages located downstream. We set restoration targets according to the EU Water Framework Directive, i.e. relative abundance of 11 fish species in the reference community and optimised a restoration plan by prioritising a subset of restoration sites from the full set of identified sites, using the conservation planning software Marxan. Out of the 66 potential gravel bars, 36 sites which were mainly located in the downstream section of the system were selected, reflecting their cost-effectiveness given that fewer barriers needed intervention. Due to the limited overall number of sites that experts identified as being suitable for restoring spawning habitat, reaching abundance-targets was challenged. We conclude that coupling systematic river restoration planning with expert judgement produces optimised restoration plans that account for on-the-ground implementation constraints. If applied, this approach has a high potential to enhance overall efficiency of future restoration efforts.

Exploring the Capacity of Water Framework Directive Indices to Assess Ecosystem Services in Fluvial and Riparian Systems: Towards a Second Implementation Phase

We explored the capacity of the biological and hydromorphological indices used in the Water Framework Directive (WFD) to assess ecosystem services by evaluating the ecological status of Spanish River Basins. This analysis relies on an exhaustive bibliography review which showed scientific evidence of the interlinkages between some ecosystem services and different hydromorphological and biological elements which have been used as indices in the WFD. Our findings indicate that, of a total of 38 ecosystem services analyzed, biological and hydromorphological indices can fully evaluate four ecosystem services. In addition, 18 ecosystem services can be partly evaluated by some of the analyzed indices, while 11 are not related with the indices. While Riparian Forest Quality was the index that was able to assess the largest number of ecosystem services (N = 12), the two indices of macrophytes offered very poor guarantees. Finally, biological indices related to diatoms and aquatic invertebrates and the Fluvial Habitat Index can be related with 7, 6, and 6 ecosystem services, respectively. Because the WFD indices currently used in Spain are not able to assess most of the ecosystem services analyzed, we suggest that there is potential to develop the second phase of the WFD implementation taking this approach into consideration. The incorporation of the ecosystem services approach into the WFD could provide the framework for assess the impacts of human activities on the quality of fluvial ecosystems and could give insights for water and watershed management in order to guarantee the delivery of multiple ecosystem services.

Managing aquatic ecosystems and water resources under multiple stress--an introduction to the MARS project

Water resources globally are affected by a complex mixture of stressors resulting from a range of drivers, including urban and agricultural land use, hydropower generation and climate change. Understanding how stressors interfere and impact upon ecological status and ecosystem services is essential for developing effective River Basin Management Plans and shaping future environmental policy. This paper details the nature of these problems for Europe's water resources and the need to find solutions at a range of spatial scales. In terms of the latter, we describe the aims and approaches of the EU-funded project MARS (Managing Aquatic ecosystems and water Resources under multiple Stress) and the conceptual and analytical framework that it is adopting to provide this knowledge, understanding and tools needed to address multiple stressors. MARS is operating at three scales: At the water body scale, the mechanistic understanding of stressor interactions and their impact upon water resources, ecological status and ecosystem services will be examined through multi-factorial experiments and the analysis of long time-series. At the river basin scale, modelling and empirical approaches will be adopted to characterise relationships between multiple stressors and ecological responses, functions, services and water resources. The effects of future land use and mitigation scenarios in 16 European river basins will be assessed. At the European scale, large-scale spatial analysis will be carried out to identify the relationships amongst stress intensity, ecological status and service provision, with a special focus on large transboundary rivers, lakes and fish. The project will support managers and policy makers in the practical implementation of the Water Framework Directive (WFD), of related legislation and of the Blueprint to Safeguard Europe's Water Resources by advising the 3rd River Basin Management Planning cycle, the revision of the WFD and by developing new tools for diagnosing and predicting multiple stressors.

Evaluation of ecological risk of metal contamination in river Gomti, India: a biomonitoring approach

The aim of this study was to evaluate the extent of heavy metal pollution in river Gomti and associated ecological risk. River water, sediments and locally abundant mollusk (Viviparus (V.) bengalensis) were sampled from six different sites and analyzed for seven metals: Cadmium (Cd), Chromium (Cr), Copper (Cu), Manganese (Mn), Nickel (Ni), Lead (Pb) and Zinc (Zn). Mean metal concentrations (mg/l) in river water were 0.024 for Cd, 0.063 for Cr, 0.022 for Cr, 0.029 for Mn, 0.044 for Ni, 0.018 for Pb and 0.067 for Zn. In river sediments, the concentrations (mg/kg dry wt) were 5.0 for Cd, 16.2 for Cr, 23.2 for Cr, 203.2 for Mn, 23.9 for Ni, 46.2 for Pb and 76.3 for Zn, while in V. bengalensis mean metal concentrations (mg/kg, dry wt) were 0.57 for Cd, 12.0 for Cr, 30.7 for Cu, 29.9 for Mn, 8.8 for Ni, 3.6 for Pb and 48.3 for Zn. Results indicated elevated concentrations of Cu, Zn and Mn in V. bengalensis as compared to other non-essential elements. Potential ecological risk (RI) in sediments showed high to very high metal contamination. Cluster analysis indicated that Pb, Zn, Cd and Ni in sediments may have anthropogenic sources. The findings thus suggest heavy metal contamination of river water and sediments have reached alarming levels, which is well corroborated by elevated level of metal accumulation in V. bengalensis.