Last spring, the municipality of Breclav entrusted the responsibility of abandoned former agricultural land to the local branch of the environmental organization Brontosaurus, to ensure the restoration of the ecosystem and use the space to carry out educational activities on environmental issues. These 5,000 square meters of the floodplain of Krce ceased to be exploited due to frequent flooding, before being colonized by invasive plants which significantly reduced the biodiversity. With long-term efforts and the right methods, Brontosaurus volunteers hope to transform this space into a haven for wetland-dependent flora and fauna made vulnerable by global warming. Brno Daily’s Coline Béguet followed them over this summer, to find out how the project is going. Photo credit: Coline Beguet / Brno Daily.
Breclav, 2 Oct. (BD) – Wetlands, ponds and swamps, have the dual characteristic of being both particularly valuable in terms of biodiversity and particularly sensitive to global warming. “Climate change manifests in our country by increasing temperatures. This leads to the problem that a number of ponds have a lack of water in the summer months, as not enough water flows in the streams that supply the ponds. Also, with a higher temperature, there is also more evaporation not only from ponds and wetlands, but the landscape as a whole,” explains Filip Šálek, biologist and volunteer at the Břeclav branch of the environmental organisation Brontosaurus.
“Many ponds are a living space for a number of specially protected animal species, such as amphibians, and due to more frequent and faster drying out, the amphibians often do not have enough time to complete their life cycle of transformation from larva to adult,” continues Šálek. “This leads to a gradual impoverishment of the population and may eventually lead to its extinction.” The extent of this habitat type is therefore significantly reduced not only quantitatively, but also qualitatively: “The ponds are significantly overheated, the quality of the water deteriorates and with this the living conditions for fish. Very often there are deaths of entire fish colonies, but it is also problematic for birds, because they then do not find enough food in such ponds.”
While the priority remains to slow climate change, certain measures can be taken to mitigate its already present effects and limit the impact on biodiversity. However, there is no miracle solution and everything must be thought out in complexity. “If we are talking about helping to improve living conditions due to climate change, there is no simple answer at all and certainly not a local solution,” says Šálek. “When stocking ponds, we can count on a reduced fish population so that there is no surpopulation of fish in drying ponds and therefore avoid a significant deterioration of water quality. For wetlands, we can build new wetlands and ponds or deepen existing ones in wet places with enough water. The purpose is that the animals that use the ponds have new places to live.”
One of the priorities is to avoid the extinction of the most vulnerable species. In the Czech Republic, notes Šálek, “there are a number of endangered birds. In recent decades, birds tied to agricultural landscapes and wetlands have been significantly threatened. These habitats were much more common in the Czech Republic in the past.” Birds aren’t the only ones to worry about, but, fortunately, “with a few exceptions, almost all amphibians are protected by Czech legislation and are included in the list of specially protected animals.”
The vegetation of wetlands is also impacted by the rise in temperatures and the irregularity of rainfall. At Krče, the most obvious symptom of global warming is the omnipresence of invasive plants. Lance-leaved asters cover the majority of the floodplain that Brontosaurus has just taken over. This plant native to the American continent was imported for the purpose of serving as an ornamental plant. Unfortunately, the weather conditions created by climate change have made it easier for this plant to escape from gardens and colonize the wetlands of Moravia. Indeed, this plant cannot normally spread and survive so easily in the wild in Central Europe because the summers are too short for it to complete its flowering, produce seeds, and therefore ensure its reproduction independently. However, earlier springs and milder autumns have helped it to gain its independence and hastened its spread, to the detriment of local plants.
Creating space to allow local plant species to grow
To remedy this in an ecological way, Jakub Těšitel, a botanical researcher at Masaryk University, had an idea: to use a species of Central Europe indigenous plant which has the particularity of being a parasitic plant in order to get rid of the lance-leaved asters. Parasitic plants ensure their subsistence by attaching to the roots of other plants in order to obtain the resources they need. With the help of young people and highschoolers who came to participate in an environmental awareness summer camp organized by Brontosaurus, Těšitel was able to test this technique. While a group of the young volunteers were scavenging the invasive American plants, another group was collecting seeds of the parasitic European plant by hand. The latter were then sown, in the hope of seeing the local vegetation regain control of the meadow next summer. If the strategy proves effective, it could then be applied to a larger part of the area of the Břeclav floodplains affected by the lance-leaved asters.
Unfortunately, these are not the only invasive plants present which are not native to Central Europe. In Krče, one can also find common milkweed, also called the butterfly flower. It is also a plant native to North America, where it plays an important role in the ecosystem since monarch butterflies feed on it. In Europe, on the other hand, their presence is not desirable because they are not part of the ecosystem, and therefore do not play a necessary role there. Moreover, they tend to spread rapidly, choking out and replacing the local vegetation that is necessary for the local fauna.
They recently arrived in the area and are not yet as numerous as the lance-leaved asters, but their spread could prove even more problematic as they would be even more difficult to eliminate. Těšitel therefore decided, in this particular case, to use strong-arm tactics. Even if he is against the use of chemical herbicides, this appears to be the only possibility to avoid a bigger problem. However, in order to limit the impact on the ecosystem and the surrounding vegetation, the product was applied locally with a brush on the head of each of the common milkweeds.
“Only time will tell how successful our plan will be.”
By launching this project, the members of Brontosaurus Breclav set themselves a challenge. The primary ambition is to create a sanctuary for plant and animal species dependent on these wetlands threatened by climate change, its consequences and the arrival of invasive plants. “By building the Krče wetland center, we expect to attract, for example, some species of woodpeckers, plovers and voodoos, as well as black and white storks. Among the amphibians, it could be a place for wood frogs, tree frogs, common newts and the much rarer Danube newt.” However, nothing is guaranteed in advance, which is why the volunteers are taking small steps and “only time will tell how successful our plan will be.”
When the restoration of the ecosystem has progressed sufficiently, Krce should become accessible to the public. Brontosaurus wants to make it a place for Breclav inhabitants to meet nature and educate people about environmental issues, which could take the form of an educational trail with written explanations of the fauna and flora of wetlands. However, the exact modalities remain to be defined because the right balance will have to be found between the service provided to the public and the preservation of the newly rebuilt and vulnerable ecosystem.
