| Newsletter November 24, 2022 |
|
|
|
Swimming ponds are species-rich biotopes that offer refuge to many endangered animal and plant species. In general, all local visitors and immigrants are welcome guests. This applies to frogs, newts and birds, dragonflies and aquatic insects, small planktonic crustaceans and much more. But there are also exceptions that have no place in a swimming pond, as they disturb the biological balance.
This includes all ducks. Not that they don't like our bathing waters. On the contrary, they would love them! But they would destroy them at the same time. Ducks like to eat tender aquatic plants, snails, frog spawn and tadpoles. And they leave their feces and with it all the intestinal bacteria and nutrients that we don't want in our bathing water. The previously invitingly clear water turns into a cloudy broth.
Ducks are also commonly infected with cercariae, flukes that live parasitically in their intestines. They excrete eggs with the droppings, which develop into free-swimming larvae in the water, which in turn infest aquatic snails. After a life cycle in the snails, they leave the intermediate host in a new larval form and try to penetrate the skin of the duck legs and there transform themselves again into flukes. It can happen that the larvae mistake us for the ducks. They die when they try to penetrate human skin. They cause itchy reddened skin, similar to mosquito bites, the so called swimmer's itch. The symptoms usually disappear after a few days without treatment. Ducks, swans and geese have no place in a swimming pond and have to be driven away if they should show up.
|
|
|
|
In the Sa Marina pilot project, we are working on a holistic water concept. The aim is to prove that villas on large plots can become water self-sufficient. The entire water consumption is to be covered by rainwater.
In Sa Marina, the rainwater that does not seep away in time (superficial run off) is collected on an approximately 12,000 m2 large sub-plot with different surfaces (open rock, forest, terraces with infiltration ditches and permaculture). A part is directed into the biotope shown above. This serves biological diversity and is designed in such a way that it can dry out in midsummer. It is therefore a "temporary freshwater biotope" and will hopefully serve as spawning water for the Balearic green toad in the future.
Once the biotope is full, the excess water flows into an underground water reservoir.
This summer, a climate station with sensors for precipitation, temperature, wind speed and direction etc. was installed. In connection with the sensors of the TU Milan, installed in the rainwater tank, it is now possible to control, almost in real time, how much rain falls in which time frame, how long it takes for the water running off the surface to actually reach the tank and what amount of water can be harvested.
The previously calculated amount of water to be collected was thus confirmed in a practical test! Converted to the total area of the property (8.6 ha), the annual precipitation and the days with heavy rain, the result proves that enough surface water can be collected to cover the total consumption of a large villa. Of course, the avoidance of unnecessary water waste through large lawns and tropical gardens as well as the consistent reuse of wastewater for irrigation is taken into account. |
|
|
|
|
