Donyan from the water, as it was not visible for years, in particular, for a long decade, which was dry, since there are notes. In fact, 47% of the swamps are still flooded in these first days of July, which is a good sign that will help to propagate water birds and restore very punished vegetation during this time. Despite everything, this does not guarantee that the lagons are experiencing summer, including the largest, such as Santa Olalla, with an additional collateral, that observation should be extreme from the presence of cyanobacteria, which pollute water -bearing lands.
The very vision of the enclave itself is a call to optimism, mainly fruits of March precipitation (rain in the entire historical series), which made a stream of swamp for one and a half and a half and a half 16,000 hectares.
In addition to how much it was raining, it was especially good when he did it with greater intensity, already in the spring, which allowed streams that pour into this large space, continued to bring water in the summer. For this, it is necessary that the temperature is not particularly high, which is completed by another additional factor: the river mountain has completed its work.
This dam was built in 1998, when a disaster occurred in the Aznellar mining industry to prevent the penetration of toxic waters into the epicenter of the park. This waterproofing also works in the opposite direction, since it significantly increased the volume of water that marsh can save. And with all this compound, for example, like Guadalquivir, he retained a very high level, because it was intensively raining throughout its pool, which, in turn, led to the fact that the drainage of the swamp was slow.
Good news for birds
All this contributes to a good campaign to reproduce water birds, during the year, which also did not begin badly. Dontana in the nature of natural data of natural data about what for Morotin (12,300 pairs), martinet (1415) or spatula, with 457 pairs. In fact, even critical endangered species have successfully rose, such as Pardilla Cerceta (65 pairs), Moruna Fut (20), ordinary smoking (eight) or Pardo Porrón, with four censorship couples.
If we add to this the relief, which it implies for vegetation, which has suffered greatly in the last decade, and with it for the environmental balance, can we throw bells on the flight? No, because this does not mean that Donyan is restored, since this is a conjunctural situation that does not affect the heart of the park, which is none other than its aquifer.
To this we must add as a sign that it is so typical that it is never raining to the taste of everyone, that the long flow of the swamp also has its own face B, which is not precisely positive. Scientific euphemism lies in the fact that this situation “can contribute to less desirable environmental processes”, such as the proliferation of invasive species. Here is Azolla Aquatic Fern or numerous species of exotic fish.
Bacteria that pollute water
But most of all it is worried that it also encourages cyanobacteria, which with the appearance of algae produce toxins that pollute water and reduce oxygen in them. Its presence has already been discovered, and this enhances special monitoring, taking into account its “potential influence on the quality of water and biodiversity”, points from the biological station of Donyan.
These bacteria can produce toxins that cause skin irritation and mucous membranes, gastrointestinal problems, and in more severe cases – liver or neurological damage. In addition, cyanobacteria flowers can reduce dissolved oxygen in water, affecting water life and causing mortality of fish.
This is that it affects the surface, but the problem is really underground. “The critical situation of the underground aquifer limits the complete restoration of other fundamental ecosystems of the park, such as temporary lagons,” says in this regard from the biological station. Water -bearing lands do not recharge with the rain, but depend on the aquifer: when their table rises enough to appear on the surface, this is when the lagons bloom.
Bad times for lagoon
These soil waters are very slowly charging when rain rains manage to get into the ground. The problem is that it is re -executed – therefore, it was officially recognized in 2020 – with holes on the water table up to 20 meters, which make rapid restoration impossible, especially if water is supported to maintain unstable intensive agrarian activity for this environment.
“The influence of climate change, super-exploration of water-bearing horizons and water pollution due to the intensive agricultural model led to the largest environmental reserve in Europe to a progressive decrease,” they regret the Seo-Birdlife when it comes to the approach to summer. The “alarming situation” of its ecosystems brought in 2023 to the International Union to preserve nature (MSOP) to remove the park from its green list, which it is still not returning.
Among the main victims of this situation are temporary lagons, many of which have disappeared in recent decades. The last census (which has two decades), placed in almost 3,000 people who exist in Donyan, most of the seasonal and small size. In March, it was found that 220 lagoon was flooded, of which only 54 endured until today, and the predictable thing is to dry with the current heat wave.
Will Santa Olalla dry again?
This is normal at the end of the day, because they are temporary, but this is that “the situation remains anxious” for the largest, and that today it has been considered constant, for example, sweet or holy Olall. The latter is the largest of all, and dried up for three years, which never happened before, and “indicates the seriousness of the deterioration of the water supply system of Donyan”, they indicate a biological station. In fact, and, despite everything that fell, there was no connection between the lagons, which was previously ordinary.
Will it be saved this year? Well, although it was rain, it cannot be guaranteed: it will depend on whether we have a very rude summer in the meteorological and, above all, the state of the aquifer, which needs much more for lifting the heads. The “critical situation”, which was dragged by water -toe, is confirmed in the score charged in Santa Olall, with its increasingly reduced limits and a silent invasion of land vegetation, ”a process that directs it to its disappearance.”
