The regulatory backdrop gives the work its urgency. The revised Urban Wastewater Treatment Directive, (EU) 2024/3019, extends binding treatment obligations to all urban agglomerations of at least 1000 population equivalents. That threshold matters because small communities, often dismissed as marginal polluters, collectively exert significant pressure on roughly 11 percent of the European Union’s surface water bodies. Previous directives largely left these agglomerations outside the strictest requirements, and the resulting nutrient loads, particularly phosphorus, continue to drive eutrophication in rivers, lakes and coastal waters. Member states now face the task of upgrading hundreds of small plants, and the central question is which technology can deliver compliance without imposing costs that small municipalities cannot bear.

Nature-based solutions offer an appealing answer. Constructed wetlands use planted beds and microbial communities to remove organic matter, nitrogen and pathogens, operating with minimal energy input and low maintenance demands compared with conventional activated sludge systems. The Renaturwat innovation lies in the substrate. Drinking water treatment generates large volumes of aluminium-based sludge, a residue that is typically landfilled. Because aluminium hydroxides bind phosphate strongly, the sludge acts as an efficient adsorbent when used as wetland fill material, capturing phosphorus that would otherwise flow into receiving waters. This closes a loop within the urban water cycle: a by-product of one treatment process becomes the active ingredient of another, embodying circular economy principles in a way that regulators and funders increasingly demand.

Quantifying the full value of such systems, however, has long been the weak link in the argument. Conventional cost-benefit analysis captures capital expenditure, operating costs and, at best, the market value of reclaimed water. It says nothing about biodiversity gains, carbon sequestration, landscape amenity, habitat for fauna and flora, or the recreational and educational value of a green infrastructure that doubles as a small wetland ecosystem. These non-market benefits are real, and environmental economists have spent decades developing methods to estimate them, but applying them consistently to a specific treatment upgrade at a specific site has remained challenging. The Valencia team, led by Vicent Hernández-Chover of the University of Valencia’s Water Economics Group together with Carmen Hernández-Crespo of the Universitat Politècnica de València, addressed the gap by combining two established techniques into a single framework.

The first component is the AMUVAM method, an analytic multicriteria valuation approach originally developed for valuing environmental assets such as the Pego-Oliva wetland, and paired here with the Analytic Network Process, or ANP. Where simpler methods treat ecosystem services as independent line items, ANP acknowledges that they interact: water availability supports fauna and flora, which in turn underpin cultural and recreational values, while regulating services feed back into all of the others. To capture this web of interdependencies, the researchers convened a panel of twelve multidisciplinary experts who performed pairwise comparisons, judging the relative influence of each service on the others. The mathematical machinery of ANP then converts those judgments into weighted priorities that reflect the network structure rather than a flat checklist.

The second component is monetisation. Once each ecosystem service carries a weight reflecting its relative importance, the framework needs a pivot value to translate those weights into euros. The team used the market price of drinking water supply in Spain, €1.09 per cubic metre, as that anchor. The logic is pragmatic: water is the service that society already pays for through tariffs, so its price provides a defensible, policy-relevant benchmark against which the other, unpriced services can be scaled. This choice avoids the volatility and controversy of hypothetical willingness-to-pay surveys while keeping the valuation grounded in an observable market signal that water utilities and regulators already use.

The results are striking in their internal consistency. Water availability emerged as the dominant ecosystem service, accounting for 33.27 percent of total relevance, which is unsurprising in a Mediterranean region where drought and water stress are recurring realities. Aggregated by category, provisioning services took 42.23 percent of overall relevance, followed by fauna and flora at 25.84 percent, cultural services at 22.54 percent, and regulating services at 9.40 percent. The prominence of biodiversity-related values in a small treatment wetland underscores how much ecological value these systems generate beyond their nominal job of cleaning effluent. It also suggests that decision frameworks which ignore fauna, flora and cultural dimensions systematically understate the case for nature-based treatment.

Translated into money over a 25-year horizon, the benefits are substantial. The Carrícola system generates approximately €242,200 in economic value, while the larger Los Monasterios installation produces around €880,726. Set against the costs of implementing and maintaining the wetlands, these figures yield benefit-cost ratios of 6.6 to 7.5, meaning that every euro invested returns roughly seven euros in combined market and non-market value. Crucially, the team tested the robustness of these estimates under conservative scenarios, and the ratios remained above unity even when assumptions were pushed toward pessimism. For municipal decision-makers accustomed to treatment upgrades that are pure cost centres, a sevenfold return is a persuasive number.

The methodological significance extends beyond the two Spanish case studies. By making the valuation chain explicit, from expert judgments about ecosystem service interdependencies, through network-based weighting, to monetisation against a real market price, the AMUVAM-ANP framework produces numbers that can be audited, replicated and adapted to other sites. Sensitivity analysis, a standard tool for testing how model outputs respond to changes in inputs, supports the credibility of the results. The approach also aligns with a broader movement in environmental accounting, traceable to landmark work on the value of global ecosystem services and to the Common International Classification of Ecosystem Services, which seeks to embed natural capital into routine decision-making rather than leaving it as an afterthought in environmental impact statements.

For the thousands of small European agglomerations now facing compliance deadlines under the new directive, the implications are concrete. Constructed wetlands enhanced with recovered treatment sludge offer a pathway that satisfies phosphorus removal targets, reuses a waste stream, operates cheaply, and generates a bundle of ecosystem services whose economic weight can now be demonstrated rather than asserted. The LIFE Renaturwat results provide the transparent, replicable economic basis that funding applications, tariff negotiations and procurement decisions have often lacked. As water stress intensifies across the Mediterranean and beyond, the ability to show that a wetland beside a small treatment plant is not merely compliant infrastructure but a productive natural asset may prove to be the argument that finally tips investment toward nature-based solutions at scale.

Subject of Research: Economic valuation of nature-based constructed wetland systems for water reuse in small wastewater treatment plants

Article Title: Integrating multicriteria analysis and economic valuation to assess nature-based water reuse systems (LIFE Renaturwat)

Article References: Hernández-Chover, V., Castellet-Viciano, L., Bellver-Domingo, Á., Hernández-Sancho, F., & Hernández-Crespo, C. (2026). Integrating multicriteria analysis and economic valuation to assess nature-based water reuse systems (LIFE Renaturwat). Environmental Science and Pollution Research. https://doi.org/10.1007/s11356-026-38244-3

Image Credits: AI Generated

DOI: 10.1007/s11356-026-38244-3

Keywords: constructed wetlands, water reuse, ecosystem services valuation, nature-based solutions, circular economy, phosphorus removal, wastewater treatment, multicriteria decision analysis, AMUVAM, analytic network process, EU Urban Wastewater Treatment Directive, LIFE Renaturwat

The research, conducted by Malihe Erfani of the University of Zabol and Fatemeh Jahanishakib of the University of Birjand in Iran, introduces what the authors call a cyclical-incremental approach, abbreviated CIA. Rather than treating environmental assessment as a one-off exercise completed before construction begins, the framework builds strong feedback loops connecting the early steps of EIA and ecosystem service valuation. The core idea is that assessment should not be a single snapshot but a cycle: an initial round of valuation is followed by monitoring, and the resulting data feed back into refined estimates, with the process repeating incrementally over the life of a project. According to the authors, this design is intended to improve the realism and objectivity of EIA through at least two assessment rounds, allowing predictions made before a project is built to be checked, corrected, and sharpened against what actually happens on the ground.

The conceptual move at the heart of the framework is deceptively simple but consequential. Ecosystem service valuation has long been promoted as a complement to environmental decision-making, capable of expressing ecological change in units that economists and finance ministries understand. But in practice, the two streams of analysis—EIA on one side, monetary valuation on the other—have often run in parallel without truly informing each other. Earlier scholarship has noted that EIA documents frequently fail to infer meaningful conclusions about ecosystem services, and that scientific shortcomings in environmental impact statements are common internationally. By embedding valuation directly within the assessment cycle, the new approach forces the environmental dimension of cost-benefit analysis to carry quantified ecological costs and benefits, making trade-offs explicit rather than leaving them buried in technical appendices.

To test the framework, the researchers applied its first round to a real and environmentally sensitive case: a sulfuric acid plant at the Sarcheshmeh Copper Complex in Kerman province, Iran. Sarcheshmeh is one of the country’s major copper operations, and sulfuric acid production is closely tied to smelting activities, with associated concerns about air quality in the surrounding industrial region. The team selected five ecosystem services for monetary assessment: habitat quality, carbon sequestration, oxygen production, food production, and forage production. These span the major categories ecologists use—provisioning services such as food and forage that people directly harvest, and regulating and supporting services such as carbon storage, oxygen generation, and the maintenance of habitat that underpin biodiversity.

The results of the first-round cost-benefit analysis were stark. Across the five assessed ecosystem services, no positive benefit was identified. The largest annual financial loss was attached to carbon sequestration, estimated at 72,877 dollars per year, followed by food production at 55,277 dollars per year. Taken together, the total annual financial loss across the five services came to 155,109 dollars, with no corresponding benefit found among the services evaluated in this initial application. The pattern is notable because it shows that both provisioning services, which supply tangible products, and supporting or regulating services, which maintain the broader ecological machinery, suffered the greatest damage. In other words, the plant’s footprint was not confined to a single category of nature’s output but eroded the landscape’s productivity and its climate-regulating capacity simultaneously.

For decision-makers, numbers of this kind change the character of the conversation. A traditional EIA might report that emissions are expected to affect vegetation or that land clearing will reduce habitat, leaving officials to weigh those statements against projections of jobs, output, and revenue. The framework’s output instead places a dollar figure on the environmental side of the ledger, directly comparable with the economic side of a cost-benefit analysis. If a project’s expected financial gains are smaller than the quantified annual losses to ecosystem services, the imbalance becomes visible in the very analysis that approval decisions rely on. The authors argue that these outputs can assist decision-makers by making the environmental costs and benefits of development projects explicit and quantifiable, a step toward what the study’s keywords describe as win-win environmental policies and honest accounting of trade-offs.

The methodological lineage of the approach is worth appreciating. Cost-benefit analysis and environmental impact assessment have been discussed together since at least 1990, when researchers examined how the two tools might be reconciled, and subsequent work has explored monetary valuation of ecosystem services under different future management scenarios, including studies of forest ecosystems facing environmental change. Other efforts have integrated ecosystem services into impact assessment through analytic and deliberative methods, or applied valuation at local scales in data-scarce regions. What distinguishes the cyclical-incremental approach is its insistence on iteration grounded in monitoring data. Ex-ante assessment—the prediction made before a project exists—is inherently uncertain, and the framework treats that uncertainty not as a flaw to be hidden but as a starting point to be progressively corrected through ex-post rounds that validate and refine the initial estimates.

That iterative structure also addresses a long-standing weakness in the EIA literature: follow-up. Scholars have documented that assessments often end once permits are granted, with little systematic checking of whether predicted impacts materialized, a gap that adaptive management frameworks have tried to fill. By requiring at least two rounds and building feedback loops back to the earliest steps of the process, the cyclical-incremental approach institutionalizes follow-up as part of the valuation itself. Monitoring data collected after a project begins operating can reveal whether the predicted losses to carbon storage or food production were overestimated or underestimated, and the valuation can be recalculated accordingly. Over successive cycles, the estimates converge on reality, and the cost-benefit analysis that informs ongoing management decisions becomes progressively more trustworthy.

The Iranian case study also illustrates the practical challenges of applying such methods in data-scarce settings. Valuing services like carbon sequestration and oxygen production requires biophysical models of vegetation and land cover, while food and forage production depend on agricultural and rangeland data, and habitat quality demands ecological assessment of the affected area. The authors draw on prior economic valuation work in Kerman province and on spatial analysis techniques, reflecting a growing body of research that uses remote sensing and geographic information systems to characterize atmospheric and land-use conditions around industrial sites in the region. The study was carried out partly under a research project supervised by Iran’s Department of Environment, with support from the University of Zabol, indicating institutional engagement at the level of the national environmental authority.

The authors are careful to frame the published results as the first round of a longer process, noting that subsequent rounds using monitoring data are required to validate and progressively refine the application. Even so, the demonstration carries weight beyond a single acid plant in Kerman. Mining and heavy industry worldwide face intensifying scrutiny over their effects on ecosystem services, with studies from open-pit coal mines in semi-arid regions to mining landscapes in Ghana documenting substantial losses in the economic value of nature’s outputs. As governments and lenders increasingly demand that environmental costs be internalized in project economics, frameworks that can produce defensible, repeatable, and monetized estimates of ecological change are likely to attract attention. The cyclical-incremental approach offers a template: quantify the services at stake, price the changes, feed the results into cost-benefit analysis, and then return after the machinery starts running to check the math against the living world. If the approach performs as designed across future rounds, the environmental ledger may finally begin to balance against the financial one.

Subject of Research: Integrating ecosystem service valuation into environmental impact assessment and cost-benefit analysis for development projects

Article Title: Integrating Environmental Impact Assessment and Ecosystem Service Evaluation in Cost-Benefit Analysis: A Cyclical-Incremental Approach

Article References: Erfani, M., & Jahanishakib, F. (2026). Integrating Environmental Impact Assessment and Ecosystem Service Evaluation in Cost-Benefit Analysis: A Cyclical-Incremental Approach. Environmental Management, 76(9), Article 316. https://doi.org/10.1007/s00267-026-02628-5

Image Credits: AI Generated

DOI: 10.1007/s00267-026-02628-5

Keywords: environmental impact assessment, ecosystem services, cost-benefit analysis, monetary valuation, carbon sequestration, habitat quality, food production, mining, Iran, environmental management, EIA follow-up, sustainability

Ecosystem services, broadly speaking, refer to the benefits that humans derive from nature. These encompass a variety of functions such as pollination of crops, purification of water, and provision of recreational opportunities, all of which are fundamental to sustaining life. Understanding these services is crucial, particularly as human activities increasingly encroach upon natural landscapes. The consensus among environmental scientists is clear: without careful assessment, we risk losing these invaluable resources forever.

The study’s authors have meticulously gathered data on the ecosystem services provided by the Ikogosi Warm Spring and Olumirin Waterfall, both of which are not only important natural resources but also sites of cultural significance. The warm spring is renowned for its unique thermal properties and health benefits, attracting numerous visitors who seek its therapeutic waters. Similarly, Olumirin Waterfall, with its breathtaking cascades and surrounding forest, presents a vital habitat for biodiversity while offering recreational opportunities for ecotourism.

The researchers employed a comparative assessment methodology to evaluate these two ecosystems side by side. This innovative approach allowed for a deeper understanding of their respective strengths and weaknesses. The findings suggest that while both ecosystems provide vital services, the specific contributions they make can vary significantly based on various environmental and human factors. Such information is invaluable for local policymakers, as it sets the stage for informed decision-making regarding conservation strategies.

Through various models, the research reveals the economic value derived from ecosystem services generated by these two landscapes. This valuation process provides a quantifiable measure that can be used to advocate for sustainable practices and effective resource management. By translating ecological services into economic terms, the authors have made a compelling case for protecting these natural treasures, thus highlighting their importance in the face of urban development and climate change.

One of the most exciting aspects of this study is its potential to spark conversations about conservation efforts across Nigeria, a country rich in biodiversity yet frequently challenged by environmental degradation. The authors emphasize that innovative and sustainable management practices are essential to preserve these ecosystems, as well as the culture and economy they support. Their findings could serve as a blueprint for similar assessments in other regions, showcasing the need for a shift in how we regard our natural resources.

Additionally, the authors address the prevailing issue of data scarcity in biodiversity studies. By bringing attention to the need for comprehensive data collection, they advocate for stronger collaboration between researchers, policymakers, and local communities. Involving local stakeholders not only enriches the quality of data collected but also empowers communities to take part in the stewardship of their natural environments.

The discussion surrounding ecosystem services valuation is not merely academic; it holds significant ramifications for local and national policies. Understanding the economic frameworks that underpin ecosystem services reinforces the tangible value of nature, which often gets overlooked in conventional developmental agendas. As cities expand and populations grow, the risk of prioritizing short-term gains over long-term sustainability increases, making insights from this study even more pressing.

Public awareness and education play critical roles in ensuring the sustainability of these resources. The study authors suggest that enhancing public understanding of ecosystem services through educational programs could foster a culture of conservation. Such initiatives can help communities recognize their intrinsic connection with nature, motivating smaller, localized conservation efforts that complement larger-scale policies.

In a world facing existential threats such as climate change, it is essential to underline the interconnectedness between people and ecosystems. The researchers’ conclusions reinforce the idea that safeguarding our natural heritage is not only an environmental imperative but also an economic one. By prioritizing the conservation of Ikogosi Warm Spring and Olumirin Waterfall, we can ensure that these ecosystems continue to provide benefits for future generations.

The authors are hopeful that their study will catalyze further research into the valuation of ecosystem services in Nigeria and beyond. With increasing pressure on natural resources, interdisciplinary research could uncover new methods for assessing ecosystem health, sustainability, and the variety of services they provide. By harnessing technology and community knowledge, we can pave the way for innovative solutions tailored to the unique challenges of diverse ecosystems.

The findings from this research contribute significantly to the existing literature on ecosystem services, emphasizing the critical need for a collaborative and inclusive approach to environmental management. With a focus on equity, sustainability, and community involvement, future studies can build on these foundations to create actionable frameworks for preserving and valuing our natural world.

As the world grapples with escalating environmental crises, the insights gleaned from the ecosystems surrounding Ikogosi Warm Spring and Olumirin Waterfall serve as a vital reminder of what is at stake. By valuing these ecosystems accurately, we not only acknowledge their importance but also equip ourselves with the tools needed to protect them for years to come.

In summary, the research by Olusola J.A., Awotoye O.O., and Jegede M. serves as a wake-up call, urging us to recognize the intrinsic value of our natural ecosystems and the imperative to protect them. As we reflect on their findings, it’s crucial that we take proactive steps today in valuing and preserving these densely interconnected systems, ensuring their sustainability for the future.

Subject of Research: Valuation of ecosystem services in Ikogosi Warm Spring and Olumirin Waterfall

Article Title: Ecosystem services valuation of Ikogosi Warm Spring and Olumirin Waterfall forest: a comparative assessment

Article References:

Olusola, J.A., Awotoye, O.O. & Jegede, M. Ecosystem services valuation of Ikogosi Warm Spring and Olumirin Waterfall forest: a comparative assessment.
Discov. For. 1, 39 (2025). https://doi.org/10.1007/s44415-025-00041-0

Image Credits: AI Generated

DOI: 10.1007/s44415-025-00041-0

Keywords: Ecosystem services, Ikogosi Warm Spring, Olumirin Waterfall, environmental conservation, valuation, biodiversity, Nigeria

The genesis of SELINA’s Communities of Practice lies in a comprehensive, nearly two-year-long collaborative journey involving extensive partner engagement. Over 23 months, SELINA partners held more than 19 consortium meetings, coordinating cross-national knowledge exchange and aligning methodologies for ecosystem assessment, accounting, and valuation. This collective effort has culminated in the creation of multiple national and regional CoPs, each serving as a dedicated knowledge hub that contextualizes ecosystem data and services specific to their geographical and socio-economic realities. As a result, a substantial repository of 29 rigorously reviewed factsheets has been published, offering granular insights into biodiversity metrics, ecosystem conditions, the flow of ecosystem services, and their incorporation into economic accounts.

The SELINA CoPs are designed not merely as transient project-based gatherings but as enduring pillars of knowledge exchange and collaboration. In the short term, they function as national platforms facilitating continuous learning and networking among stakeholders during the project’s life span. These forums promote dialogues that demystify ecosystem science, making it accessible for decision-makers and industry leaders who often grapple with translating scientific findings into practical policies and innovations. By fostering shared understanding, they bridge traditional gaps between ecological research and policy implementation, enabling more informed and sustainable choices.

Beyond the immediate project timeframe, the initiative envisions intermediate and long-term objectives that embed resilience into these communities. Intermediate goals focus on institutionalizing CoPs as formal networks capable of sustaining ongoing cooperation beyond initial funding periods. This involves establishing governance structures, fostering trust among participants, and encouraging resource sharing to facilitate knowledge continuity. Ultimately, the aspiration is to cultivate a robust and self-sufficient pan-European network of CoPs, interconnected yet autonomous, continuing to disseminate expertise and best practices well into the future.

A notable feature of the SELINA CoP framework is its emphasis on cross-national collaboration. Recognizing that ecological challenges often transcend borders, the initiative encourages CoPs from different countries to engage in joint dialogues, exchange best practices, and collaboratively tackle shared issues. These interactions, facilitated through SELINA-organized events or self-initiated community activities, enable the pooling of diverse experiences and innovative approaches. This collective intelligence fosters scalable solutions and spurs the harmonization of ecosystem accounting methodologies across Europe, strengthening the foundations for a unified environmental governance landscape.

Underpinning the CoPs is an advanced science-policy interface that integrates cutting-edge research with practical policymaking tools. The factsheets produced by the CoPs synthesize complex datasets on ecosystem condition and services into comprehensible formats, often employing standardized indicators and accounting frameworks aligned with international standards such as the System of Environmental-Economic Accounting (SEEA). These resources assist stakeholders in quantifying ecosystem contributions to economic and social well-being, enabling the incorporation of natural capital considerations into national statistics, corporate reporting, and public policy evaluations.

Moreover, through these CoPs, SELINA is addressing a perennial obstacle in environmental governance: the fragmentation of knowledge domains. Many ecosystem-related decisions have historically suffered from siloed information streams, lacking integration between ecological science, economic valuation, and social dimensions. The CoPs act as integrative platforms where multidisciplinary expertise converges, facilitating holistic analyses of ecosystem functionality, service flows, and their socio-economic impacts. This systemic perspective is crucial for crafting adaptive management strategies that are resilient to environmental changes and socio-economic uncertainties.

Communication and outreach also constitute vital components of the Communities of Practice model. SELINA has developed a dedicated digital hub where CoP activities, updated factsheets, and event information are continuously published. This ensures transparency, promotes wider stakeholder engagement, and maintains the relevance of the platform amidst evolving environmental challenges. By leveraging digital tools alongside traditional meetings, SELINA enhances the accessibility of ecosystem knowledge, thus broadening its impact beyond immediate participants to reach policymakers, researchers, and the public alike.

Importantly, the CoPs provide a valuable testing ground for methodological innovations in ecosystem accounting and valuation. Through iterative learning processes and mutual feedback loops within communities, best practices are refined and adapted to diverse contexts. This empirical approach enhances the robustness of ecosystem service assessments and their policy applicability, providing evidence-based inputs for ecosystem restoration, conservation funding, and sustainable resource management initiatives at multiple governance levels.

The SELINA project’s integration of CoPs exemplifies a forward-looking paradigm in environmental governance — one that prioritizes stakeholder inclusivity, knowledge co-production, and multi-level cooperation. By fostering enduring, dynamic networks that transcend disciplinary and national boundaries, SELINA contributes significantly to the evolving landscape of ecosystem management in Europe. Its emphasis on embedding natural capital considerations systematically into economic and policy frameworks aligns with global sustainability goals and underpins Europe’s commitment to the EU Green Deal and the UN Sustainable Development Goals.

For professionals, policymakers, and researchers intrigued by this novel approach, SELINA’s new Communities of Practice webpage offers a gateway to explore ongoing initiatives, factsheets, and future events. As the CoPs continue to mature and generate tangible outcomes, they represent a compelling model for scaling ecosystem knowledge integration worldwide. Those interested in contributing to or learning from these vibrant communities are encouraged to connect with national contact points or SELINA project leads, fostering a growing network dedicated to ecosystem sustainability.

In summary, the SELINA Communities of Practice initiative is not just a scientific endeavor but a socio-political innovation in environmental stewardship. Its multi-tiered strategy, uniting scientific rigor with stakeholder engagement and practical tools, paves the way for more informed, transparent, and collaborative ecosystem governance models. As challenges associated with biodiversity loss, ecosystem degradation, and climate change intensify, such integrative platforms are indispensable for harnessing collective expertise towards resilient and sustainable futures.

Subject of Research: Integration of ecosystem knowledge into decision-making processes through Communities of Practice in the SELINA project.

Article Title: SELINA’s Communities of Practice: Catalyzing Sustainable Ecosystem Governance Across Europe

Web References:
https://project-selina.eu/communities-of-practice
http://www.project-selina.eu
https://www.linkedin.com/company/project-selina
https://bsky.app/profile/selinaproject.bsky.social
https://www.youtube.com/@SELINA_HorizonEU

Image Credits: Pensoft Publishers

Keywords: Scientific organizations, Scientific publishing, Ecosystem accounting, Natural capital, Sustainability, Environmental governance, Biodiversity integration