Europe’s wetlands may look like a collection of separate lakes, marshes, floodplains and lagoons, but water rarely respects the boundaries drawn on a map. A new study by A.E. Robinson and F. Jaramillo, published in Communications Earth & Environment, provides a continent-scale baseline of surface-water connectivity across European Ramsar wetlands, offering scientists a way to see how these internationally protected ecosystems are physically linked. The work matters because connectivity is one of the hidden properties that determines whether wetlands can function as living networks or become isolated fragments. When water can move between habitat patches, it can transport nutrients, sediments, organisms and genetic material. When those pathways are blocked or disappear, the ecological consequences may spread far beyond a single wetland.
The researchers focus on surface-water connectivity, a concept that describes how directly and continuously water bodies are connected across a landscape. Connectivity can occur within a wetland, between neighboring wetlands, or across larger river and floodplain systems. It may be permanent, seasonal or episodic, emerging only after heavy rain, snowmelt or flooding. This distinction is crucial. Two wetlands can appear close together geographically while remaining functionally disconnected if roads, embankments, drainage channels, dams or urban development interrupt the movement of water. Conversely, wetlands separated by considerable distances may become connected during seasonal floods. A baseline that captures these patterns gives researchers a reference point against which future losses or recoveries can be measured.
Ramsar wetlands are especially important for this kind of analysis because the Ramsar Convention identifies sites recognized as internationally significant for biodiversity, water regulation and ecological processes. The designation protects individual places, but wetland species and water flows operate across much wider areas. Migratory birds may use several wetlands during a single journey, while fish, amphibians, aquatic invertebrates and plant propagules can depend on temporary links between water bodies. Connectivity also influences the movement of dissolved organic matter, nutrients and sediment. By examining the surface-water relationships among European Ramsar sites, the study addresses a central conservation problem: whether protected areas are functioning as connected ecological systems rather than as isolated points of protection.
The idea of a baseline is as important as the map itself. Environmental change is often detected by comparing present conditions with an earlier or reference state, but that comparison is difficult when connectivity has never been systematically described. A baseline can establish where surface-water links currently exist, where they are intermittent, and where apparent protection does not necessarily guarantee hydrological connection. It can also support the development of indicators for wetland condition. Instead of asking only how much wetland area remains, scientists can ask whether water still moves through the system, whether seasonal inundation reaches neighboring habitats, and whether human infrastructure has severed pathways that once allowed ecological exchange.
That perspective is increasingly urgent across Europe. Wetlands are under pressure from drainage, groundwater extraction, agricultural intensification, river regulation, infrastructure construction, pollution and climate-driven changes in rainfall and temperature. Rising temperatures can increase evaporation and lengthen dry periods, while more intense rainfall can produce short-lived floods that do not restore the same ecological functions as sustained seasonal inundation. In regulated rivers, water may be present but disconnected from floodplains because embankments prevent it from spreading across low-lying habitats. These changes can alter the timing, duration and direction of water movement. For organisms adapted to particular hydrological cycles, the loss of a brief connection can be as significant as the permanent disappearance of a pond.
A continent-wide assessment also helps reveal why local conservation decisions can produce incomplete results. Restoring vegetation or removing invasive species inside a protected wetland may improve habitat quality, but the benefits can be limited if upstream barriers prevent the arrival of clean water, sediment or aquatic organisms. Likewise, reconnecting a floodplain without considering downstream pollution or altered river flows may fail to restore the broader system. The baseline developed by Robinson and Jaramillo can therefore serve as a spatial framework for prioritizing restoration. Areas with existing connections may be valuable targets for protection, while strategically located breaks could become candidates for reconnection through barrier removal, managed flooding or redesigned water infrastructure.
The technical challenge is that connectivity is not a single, easily measured quantity. It has spatial and temporal dimensions, and its meaning depends on the process being studied. A connection suitable for a fish may not be sufficient for an amphibian, a seed or a sediment particle. Hydrologists may define connectivity through water pathways and flow duration, while ecologists may evaluate it through species movement or nutrient exchange. Remote sensing and geographic information systems can help bridge these perspectives by identifying the distribution of surface water and comparing water bodies across landscapes. Satellite observations are particularly useful for wetlands because they can repeatedly record changes in inundation over large areas, including locations that are difficult to survey from the ground. Such data can reveal seasonal expansion and contraction, but interpreting ecological significance still requires care: a visible water connection does not automatically mean that the water is deep enough, clean enough or persistent enough to support biological exchange.
The study’s broader message is that wetland conservation must move from a site-by-site model toward a network-based approach. Legal protection remains essential, but boundaries alone cannot preserve processes that cross them. Policymakers, basin managers and conservation organizations can use connectivity information when planning flood defenses, transport routes, agricultural drainage, water allocation and climate adaptation. Maintaining or restoring links between wetlands may strengthen biodiversity, improve flood regulation and increase resilience to drought by preserving alternative refuges for species. It may also help identify places where restoration could deliver benefits across an entire catchment rather than within one reserve. As Europe faces a more volatile water future, the new baseline offers something deceptively powerful: a way to measure not just where wetlands are, but whether they still operate as a connected water system.
Subject of Research: Surface-water connectivity and ecological linkages among European Ramsar wetlands
Article Title: A baseline of surface water connectivity in European Ramsar wetlands
Article References: Robinson, A.E., Jaramillo, F. A baseline of surface water connectivity in European Ramsar wetlands. Commun Earth Environ 7, 658 (2026). https://doi.org/10.1038/s43247-026-03812-5
Image Credits: AI Generated
DOI: https://doi.org/10.1038/s43247-026-03812-5
Keywords: Wetlands, Ramsar sites, surface-water connectivity, hydrology, biodiversity, ecological networks, Europe, conservation, remote sensing, restoration
