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back in 2022 we dug a series of channels to flood an area of forest next to the danu river we did this to help a struggling ecosystem that has been in Decline since the construction of a dam and the results were immediate for almost 2 years these channels have been bringing water to this flood plane Forest twice a year during the Spring and the summer floods but this year something unexpected happened the forest flooded in winter in January the whole Wetland was suddenly full of water and then the water froze creating this strange and Enchanted icy landscape it's really just a crust that's kind of hanging sort of in midair and as you walk on it um it breaks but there is no water underneath so in this video today
Adriana will put on some ice cleats to walk you through our slippery frozen flooded forest and we'll also investigate this rare phenomenon because it turns out that ice might be more important for the health of this flood plane ecosystem than we previously thought now I guess you might be wondering why we are so thrilled about seeing this place flooded it's a flood plane after all and the water is supposed to be there right well yes but this flood plan was cut off from its river by the dam and has been drying out ever since if you want to know more about what happened here I invite you to watch the first video in this flooded Forest series we have here on the YouTube channel it will explain
everything in more detail what you need to know now is that the floods that were once natural here are now controlled and timed by people the whole flood plane area is now fed water from this artificial Channel through this inflow here and the water is distributed to different places through a series of channels including the ones we constructed with our Slovak Partners bro these human controlled floods are done twice a year one in the spring and one in the summer to help Wetland species during a crucial time of growth reproduction and nesting but from time to time the roll still reverse and the river calls the shots when the danu brings exceptionally high amounts of water the dam operators have to release
some of it into the old riverbed to take the pressure off of the Hydro power plant the mass of water can also push back up the Old River and fill the flood plane from the bottom this combined effect causes the water level in the old danu to rise and a flood is born this kind of flooding is common in the summer when high rainfall combines with the snow melt from the Alps causing water levels to rise rapidly witnessing a flood like this in the winter though is much rarer so basically two quite rare things happened there was a lot of the water in the denu so our forest got flooded and then it was freezing so basically this beautiful crust of ice formed over our forest and this is how we ended up with
this incredible Frozen Forest the last time this Forest flooded in the winter was 18 years ago so you can imagine our excitement and especially Sig's excitement he is the one responsible for his storing this area and this Forest is kind of like his second child so when Adriana first went to visit the forest it was just for the sheer Joy of experiencing this icy spectacle and also capturing some shots for you guys to see it's pretty cool to see it frozen over like this I've never actually been here in the winter before these are little icicles that are kind of hanging beneath the ice like little PKA dos so you can see on this ice Mark here on the tree that the water level was a lot higher last week but it's been
retreating slowly but after a day immersed in this icy world she was hooked and wanted to know more about this little known phenomenon coincidentally the following day the Bratislava City Museum was putting on an evening lecture about ice floods on the danu and that gave us some answers it turns out that ice and winter floods used to be a common thing on the danu records from the past three centuries revealed that the river would freeze over very often it was pretty much a yearly occurrence and often the river would freeze in its full length all the way from Austria to the Black Sea the ice flows that formed on the river could be several meters high and to fight it people deployed ice breakers and
sometimes even explosives for an instance in the winter of 1947 the Air Force dropped 250 kg of bombs on the ice just below the city in an attempt to break it but it had little effect people were fighting the Ice because as it accumulated it would often create a kind of Log Jam that clogged up the river and could cause flash flooding these ice floods were catastrophic and could level entire villages to the ground but the Frozen River was also celebrated as a natural part of life because people used to enjoy Crossings in the river on horsedrawn carriages called ice today there are still three ice breakers around named brno krupina and dunai but they're not so busy these days because
the winters on the danu have changed the last big ice was recorded 70 years ago and 2017 saw the last ice flows form on the danu part of this is because of good old climate change of course but the river itself also changed it has been modified to be deeper and faster making it harder for the ice to form and although the flood that froze in our flooded Forest is really interesting it is quite different from these historical ice floods and the loss of these floods actually op some interesting new questions about the meaning of ice remember when adren said that she hadn't visited the forest in Winter before well that's part of the problem ecologists tend to focus their research on the
growing season but what we know about ecosystems in the summer cannot be applied to them in the winter this leaves us with a whole season that is significantly underst studied so the truth is that we don't actually know much about the ecological role of ice in river and ecosystems but those studies that have looked into this show that what happens here during the winter has an effect on how things unfold throughout the year experimental studies from rivers in Sweden show that areas that are flooded and covered in ice during the winter grow a richer understory with more species of wild flowers and more than half of all large rivers are seasonally covered in ice and for these Rivers ice is a force that has
the power to both create but also destroy so this car here really gives you an idea how much power even a small amount of ice can have it really took off the top layer of the bark as it in case the tree quite impressive now imagine the power of large ice blocks drifting through the riverine landscape eroding soil redistributing sediment and scouring any vegetation that stands in their way this might sound like a scene of Destruction but where some species are displaced others find opportunity it is often like this in nature and this constant change makes the river flood planes one of the most diverse and productive ecosystems on Earth so ice is probably more important for the Ecology
of rivers than we give it credit for but in addition to that it might have a significant effect on our forest this spring so last winter the channels were completely dry throughout the whole winter basically um and we're hoping that because there's so much water here now uh if the ground stays saturated then uh when we have the spring floods we should see an even bigger effect it is really exciting to be headed towards the third flood of this project with this extra potential surprise in the back the impact that this project has had in Reviving this ecosystem has been amazing to witness it has been an absolute pleasure to be a part of and if you've enjoyed the ride so far please remember that you could
support our work in projects just like this one by becoming a moss Earth member we set up all kinds of impactful projects that restore and Rew nature from native oysters in Scotland to the rainforest of the Amazon all the way to the coral reefs of Indonesia we're really hard at work across more than 20 projects to help bring back wild native ecosystems and becoming a member is cheap because we want as many people as possible to join and when we put it all together your money goes a really long way and if this is a big step for you right now then please consider subscribing to the channel it is a great zeroc cost way to help us out as well I hope you enjoy the walk through the
Frozen Forest but now I'm the one who is frozen so it's time to go home see you next time ciao
