International Day for Biological Diversity: protecting aquatic ecosystems in the face of climate challenges

Biological diversity represents the living fabric of our planet, forming the foundation of the ecosystem services essential to humanity’s survival, such as the supply of drinking water, temperature regulation, soil fertility and food security. In the modern era, this biodiversity faces systemic anthropogenic pressures, which are now being dramatically exacerbated by the tangible impacts of climate change. This negative synergy undermines natural balances and directly threatens the stability of human societies.

Against this backdrop of global crisis, aquatic ecosystems — which include rivers, lakes, groundwater, estuaries and wetlands — are on the front line of vulnerability. The global rise in atmospheric temperatures is causing a gradual warming of freshwater bodies, altering dissolved oxygen concentrations and disrupting the biological cycles of fish species and benthic macrofauna.

Furthermore, the disruption of global hydrological cycles is leading to an increased frequency and severity of extreme hydro-climatic events.

Prolonged droughts lead to severe low-water conditions, causing the fragmentation of aquatic habitats, the drying up of spawning grounds and the disruption of ecological connectivity.

Conversely, flash floods and major floods exacerbate soil leaching, draining massive flows of pollutants, nutrients and sediments into receiving environments, which accelerate eutrophication and the suffocation of these environments.

The protection of aquatic biodiversity goes beyond the scope of mere heritage conservation: it is a prerequisite for the climate resilience of our regions. Wetlands, acting as natural regulatory infrastructure, mitigate floods, maintain low-water flows and biologically purify water, demonstrating that investing in nature remains a major and essential adaptation strategy.

As a leading player in the field of water governance and capacity building, the International Office for Water is implementing a comprehensive strategy to place biodiversity protection at the heart of water resource management.

Through its public interest initiatives, the OiEau develops technical tools, coordinates networks of expertise and leads national and international projects to provide concrete responses to the environmental emergency.

Knowledge engineering is a key driver for guiding public and technical policy. It is with this in mind that OiEau manages the Water & Biodiversity Knowledge Base. This comprehensive platform centralises, structures and promotes a wide range of documentary resources, methodological guides and operational feedback. By linking the challenges of quantitative and qualitative water management with the imperatives of ecosystem conservation, this tool enables government departments, local authorities and consultancy firms to design land-use planning projects that fully respect living organisms.

Complementing the Water & Biodiversity Document Portal, this database brings together resources in various formats: texts, webinars, podcasts, infographics, datasets, etc.

It allows users to search for information using keywords or an experimental chatbot (artificial intelligence – AI), enabling queries in natural language within a curated, neutral and high-quality information framework.

To support the professional development of environmental professionals, OiEau carries out rigorous technical and regulatory monitoring, which takes the form of newsletters that enable readers to keep track of regulatory and technological developments on a day-to-day basis.

Since 2014, with financial support from the French Office for Biodiversity, OiEau has been producing the monthly Aquatic Biodiversity newsletter, a continuous and dynamic information service covering aquatic biodiversity in France and worldwide.

It is an indispensable tool for keeping stakeholders in the sector up to date with best practices in river restoration and the protection of endangered species.

The management of aquatic ecosystems transcends administrative boundaries.

This is the case, for example, with the Progiress project (Project for the Integrated Management of Surface and Groundwater Resources in the Senegal River and Senegal-Mauritanian Aquifer Basins), to which OiEau is contributing its methodological expertise.

This large-scale project aims to strengthen shared governance of water resources within a Sahelian region particularly vulnerable to climate change. By securing resources and optimising overall hydrological balances, the project contributes directly to the sustainability of critical wetlands and the preservation of endemic biodiversity on which local populations depend.

In France, OiEau is fully committed to consultation and collective action through its involvement in coordinating several networks of stakeholders.

By supporting the work of the ‘Milieux humides France’ network, OiEau facilitates synergies between public authorities, site managers, the scientific community and nature conservation organisations.

This active coordination helps to structure the sharing of experiences and standardise monitoring and restoration protocols, thereby accelerating the implementation of the national strategy to safeguard these environments of inestimable ecological value.

OiEau is also establishing itself as a hub for professional exchange by organising and actively participating in targeted technical meetings. These events provide an opportunity to share best practices and jointly develop the sector’s future responses.

Among recent initiatives, OiEau has contributed to the success of several major events:

• The web conference ‘Communicating about watercourses: practical tools and feedback’, which highlighted the importance of regional dialogue and environmental education in gaining local communities’ acceptance of ecological restoration projects.
• The webinar ‘Outdoor sports in wetlands: reconciling sporting activities and biodiversity’, focused on finding collaborative management solutions to mitigate human disturbance of wildlife whilst maintaining leisure and ecotourism activities.

In light of the need to adapt to climate change, the transfer of skills and capacity-building for those working on the ground are essential components of OiEau’s overall strategy. Through its Centre for Training in Water-related Professions (CFME), it delivers a highly specialised range of training courses directly focused on the conservation of aquatic biodiversity and the sustainable management of water systems.

These training programmes are aimed at a wide audience of technicians, engineers, biodiversity managers and decision-makers from the public and private sectors. The training modules cover crucial operational topics such as the characterisation of plant and animal biodiversity in wetlands, the monitoring of ecological quality indicators for water bodies, and the implementation of ecological engineering techniques applied to the restoration of watercourses.

Drawing on educational facilities and technical platforms that are unique in Europe, these courses place learners in real-world scenarios to master the dynamics of quantitative hydrology and the restoration of ecological connectivity.

By training thousands of professionals each year, OiEau sustains and disseminates best practices in environmental engineering.

Through this integrated and multidisciplinary approach — combining stakeholder training, knowledge engineering, science communication, the coordination of national networks and international cooperation — OiEau has established itself as an essential institutional partner in meeting the challenge of safeguarding aquatic biodiversity in an era of global climate change.