Traditional conservation approaches often rely on field studies at the local or patch scale, which, while valuable for detailed ecological assessments, are insufficient for covering the spatially extensive areas required for effective catchment-scale management. Field surveys across entire river basins are often logistically unfeasible and too limited to capture the broad-scale dynamics of species distribution under changing climate conditions. To address this gap, researchers have increasingly turned to indirect methods, particularly species distribution models, which allow for the assessment of habitat availability and potential species distributions across large geographic areas. These models provide a crucial framework for understanding how environmental changes will affect biodiversity, enabling planners to make informed decisions about where to focus restoration and protection efforts.

Species distribution models function by linking scattered data on species presence or absence to a set of environmental predictors, such as topographic, geological, and climatic variables. By combining biodiversity data from national and international databases with projected climate scenarios, these models can forecast changes in the spatial distribution of species under various future conditions. For example, studies in Switzerland have utilized such models to evaluate whether current protected areas provide sufficient habitat for floodplain fungi and plant communities. The results indicated that while many species are currently recorded within protected zones, the projected suitable habitat for many of these organisms lies outside these areas, highlighting a critical mismatch between existing conservation networks and future ecological needs.

The distinction between refugia and sanctuaries is a key concept in climate-adapted conservation planning. Refugia are areas that remain suitable for long-term species survival despite changing environmental conditions, whereas sanctuaries offer only temporary protection during extreme events or short-term fluctuations. Dispersal-coupled species distribution models help to differentiate between these two types of areas by incorporating the movement capabilities of species. For sessile organisms, such as plants and fungi, which have limited means of dispersal, the identification of true refugia is particularly important. Projections for Swiss floodplain plant communities revealed that many current protected areas are likely to become unsuitable as refugia under future climate scenarios, serving instead as short-term sanctuaries. This insight is vital for planning new protected areas that can ensure the long-term persistence of vulnerable species.

In addition to climatic factors, hydrological regimes play a pivotal role in determining habitat availability for floodplain species. Hydrological models at the reach or patch scale provide detailed predictions of changes in water availability, particularly during periods of drought. For instance, studies on the River Rhine in Germany have shown that summer discharges are projected to decrease significantly after 2050, leading to lower water levels during the vegetation period. This shift in hydrological conditions can result in the loss of habitat for species that require specific inundation frequencies, such as the White Willow. By integrating hydrological projections with ecological models, researchers can more accurately predict the spatial shifts in habitat suitability and identify areas where restoration efforts are most likely to succeed.

The practical application of these models is illustrated by the case of the Auenschutzpark Aargau in Switzerland, a floodplain conservation park established thirty years ago. This protected area serves as a valuable case study for assessing the long-term effectiveness of conservation measures. Monitoring data from the park show significant increases in the populations of several amphibian species, including tree frogs, yellow-bellied toads, and water frogs, following the restoration of floodplain habitats. The park has also supported a diverse community of ground beetles, which are indicator species for floodplain health. These findings demonstrate that protected areas can provide essential refuge for specialized terrestrial species and promote biodiversity conservation, even in the face of ongoing environmental pressures.

Despite the successes of existing protected areas, the need for new conservation zones is evident. Models suggest that current protected floodplains in Switzerland do not provide sufficient habitat for typical floodplain species under future climate conditions. Therefore, climate-adapted conservation planning must include the identification and protection of new areas that are predicted to remain suitable for long-term species survival. This approach requires a multi-scale perspective, linking catchment-scale species distribution models with reach-scale hydrological models to prioritize restoration projects. By focusing on areas that offer both current and future habitat suitability, conservation planners can build a resilient network of protected habitats that can withstand the impacts of climate change.

The integration of ecological and hydrological models also highlights the importance of considering the joint effects of past anthropogenic changes and future climate scenarios. Fragmented landscapes along rivers are particularly vulnerable to the combined impacts of habitat loss and altered hydrological regimes. Extreme flood events, which are becoming more frequent and severe due to climate change, can both disrupt and restore floodplain ecosystems. While extreme floods can lead to local extinctions and displacement of sessile species, they can also temporarily restore connectivity between floodplains and river channels, facilitating long-distance dispersal and colonization of new habitats. Understanding these dynamic processes is essential for designing conservation strategies that can adapt to the changing nature of floodplain ecosystems.

Future conservation planning for riverine biodiversity must therefore adopt a dynamic and multi-scale approach that incorporates the latest scientific insights from modeling studies. By leveraging the power of species distribution and hydrological models, planners can identify priority areas for restoration, establish new protected zones, and ensure the long-term survival of vulnerable species. The success of such efforts will depend on the ability to integrate data from various sources, including citizen science, monitoring programs, and field studies, into a coherent framework for decision-making. As climate change continues to reshape the landscape, the use of these models will become increasingly important for guiding conservation actions that are both effective and sustainable.

In conclusion, the application of models to conservation planning for riverine biodiversity under changing climate offers a promising path forward for protecting these vital ecosystems. By distinguishing between refugia and sanctuaries, predicting hydrological changes, and evaluating the effectiveness of existing protected areas, these tools provide the necessary information to make informed decisions about the future of floodplain conservation. The case of the Auenschutzpark Aargau demonstrates that targeted protection and restoration can yield significant benefits for biodiversity, but it also underscores the need for continuous adaptation and expansion of conservation efforts. As we face the challenges of a changing climate, the integration of scientific modeling with practical conservation planning will be essential for ensuring the resilience and persistence of riverine ecosystems for generations to come.

Subject of Research: Conservation planning for riverine biodiversity under changing climate: use of models

Article Title: Conservation planning for riverine biodiversity under changing climate: use of models

Article References: Fink, S., Kräuchi, N., Stofer, S., Weber, A., & Horchler, P. J. (2026). Conservation planning for riverine biodiversity under changing climate: use of models. Nature Conservation, 62, 47-62. https://doi.org/10.3897/natureconservation.62.149645

Image Credits: AI Generated

DOI: 10.3897/natureconservation.62.149645

Keywords: Conservation, planning, riverine, biodiversity, under, changing, climate, models, scientific research