Climate change
Monitoring and surveys
Climate-proof rivers
Climate change can have major effects on nature. We investigated what these effects are along the branches of the River Rhine and the River Meuse, and how we can give nature a helping hand.
Extreme weather conditions can cause drought one moment and flooding the next. This creates challenges for wildlife and for people. To prepare for this, Waardenburg Ecology, HKV lijn in water, Deltares, Radboud University, KWR, SOVON, RAVON and FLORON have visualised scenarios and schetched solutions, for OBN (VNBE).
Climate scenario
To estimate the future prospects for river nature, a climate scenario was developed that most clearly illustrated the effects of drought and increased temperatures during the growing season. The subsidence of the riverbed is also included. We also asked site managers and river authorities about their practical experiences and examined national and international literature on this subject.
Higher temperatures and desiccation
The effects of climate change are already visible in river areas. The water warms up, floodplains dry out and tributaries run dry. Drainage patterns become more erratic and the drying of floodplains in particular can cause problems because most wildlife found here is dependent on water.
According to the research, the upstream parts of the River Rhine and the River Grensmaas in particular will face further drying in the future. The associated higher water temperatures will cause an increase in the biomass of aquatic plants and algae, and also an acceleration of bacterial and chemical processes, making more nutrients available. This can lead to an increase in algae or duckweed, causing more sensitive species to lose out.
According to the research, the upstream parts of the River Rhine and the River Grensmaas in particular will face further drying in the future. The associated higher water temperatures will cause an increase in the biomass of aquatic plants and algae, and also an acceleration of bacterial and chemical processes, making more nutrients available. This can lead to an increase in algae or duckweed, causing more sensitive species to lose out.
Winners and losers
There will be winners and losers among the flora and fauna. Desiccation will mean that moist habitats such as wet softwood riparian forests, foxtail grass meadows and yellow water-lily will have difficulty along large parts of the river. River pondweed, for example, benefits from climate change, just like the swallowtail and bee-eater.
It goes without saying that fish will suffer from the drying-up of secondary waters, but decreased currents, increased temperatures and changes in oxygen levels can also cause problems. The burbot, bullhead and dace are known to have difficulty with tolerating high water temperatures in the summer. Amphibians such as great crested newts, natterjack toads and moor frogs can partly adapt because the larvae can develop more quickly, but they run into problems if their breeding waters dry up too early in the spring. Birds can suffer if their breeding or foraging area become less suitable.
In general, non-native species from all species groups have a competitive advantage because they can usually withstand higher temperatures and adapt to changing conditions better.
It goes without saying that fish will suffer from the drying-up of secondary waters, but decreased currents, increased temperatures and changes in oxygen levels can also cause problems. The burbot, bullhead and dace are known to have difficulty with tolerating high water temperatures in the summer. Amphibians such as great crested newts, natterjack toads and moor frogs can partly adapt because the larvae can develop more quickly, but they run into problems if their breeding waters dry up too early in the spring. Birds can suffer if their breeding or foraging area become less suitable.
In general, non-native species from all species groups have a competitive advantage because they can usually withstand higher temperatures and adapt to changing conditions better.
Adjust and connect
The effects of climate change can be erratic and unpredictable. This requires customisation and flexibility in management measures. Managers will always have to respond and adjust to preserve and enhance wildlife along rivers. Fortunately, there are options for mitigating measures at the local level such as retaining water for longer and increasing shade. A broader approach is needed for measures focused at the source. A key component in combatting change is strengthening the ecological network. If nature reserves are well connected and therefore large, species can move to drier or wetter places when necessary.