The diversity of Donana’s ecosystems

The diversity of Donana’s ecosystems

 

Between sand and the smell of salt there’s a very particular place; This place is called Donana. A unique place from different aspects, today we are going to talk about:

The diversity of Donana’s ecosystems.

The diversity of Donana’s ecosystems has always been changing; Donana has been different a long the time and the Donana that we know today has only been with us for approximately 6000 years. In geological time it does not even reach the blink of an eye, but in those 6000 years the ecosystems have been formed as we know them today.

The first ecosystem of Donana is the best known and currently used by people, if you think of the beach

Correlimos tridáctilo "Calidris alba"

Sanderling Calidris alba on Donana’s beach.

Correct!

It is an ecosystem in continuous change due to the action of wind and waves; sometimes with progradation (advance) and other times with retrogradation (retreat) of the coastline.

But… How is this possible?

The wind and waves move the grains of sand (littoral drift movement) molding the coastline with each storm.

Later, at the upper limit of the high tide, remains of bivalves (shells) and remains of fish can be found. The latter can be eaten by gulls (yellowlegs, black-backed gulls, etc.), also, sandpipers are usually found at this limit eating the small invertebrates. The next thing we can find are the embryonic dunes, those are in the upper limit of our ecosystem and in them we find the bravest vegetation, as it fights against the wind that hits the coast and the saline spray that is in the environment. It’s not a super power but you have to be able to. And how she does it? Using adaptations like deep roots, in the case of the marram grass Ammophila arenaria, and other types of adaptations such as coastal bugloss Equium gaditanum, sea holly Eryngium maritimum, sea daffodil Pancratium maritimum and others.

Row of dunes N.P. Doñana

 

The next ecosystem that shows us the diversity of Doñana’s ecosystems, due to proximity, are the dunes; with a close alliance between wind and sand, this ecosystem is formed over thousands of years. It is a dune system (row of dunes) that is carried by the action of the wind towards the interior of the park. The first, mobile dunes, are only retained and formed by the plant like spiny thrift Armeria pungens, helichrysum Helichrysum picardii and other species, some already mentioned above, that mold the landscape. Once we have passed this line, we reach the next dune range where species such as cade juniper Juniperus oxycedrus subsp. macrocarpa or Stone pine Pinus pinea are present. The latter forms part of the interior landscape and the dune corrals, leaving behind the passage of the dune the so-called Doñana crosses or field of crosses.

Corral dunar

Corral dune N.P. Donana

 

This ecosystem gives way to the next: the marshes. But first, as a result of the union of marshes and dunes, the vera is born. La vera is not considered an ecosystem of Doñana, it is even more ephemeral. It is an ecotone, the ecotone is born by the emergence of groundwater, given the limit between clays and sands of the soil layer. This area has incredible biodiversity and is of vital importance for the local wildlife, as it sometimes acts as a watering hole when water is scarce for herbivores and as a camping area for carnivores.

 

Tsunami incidence direction

Tsunami incidence direction

And now, the marsh. The image of the diversity of Doñana’s ecosystems, young, born from tsunamis and made from large floods that were silted up, depositing sediments and closing the ancient lacus ligustinus, an ancient Roman lake. Little by little, the Doñana that we know today will appear, one of the reasons for the greatness and diversity of Doñana’s ecosystems: The birds. Herons, egrets, eagles, bitterns, flamingos, stilts and almost 100 species only in the Doñana marshes; makes this site ideal for birdwatching.

Finally, The “coto” or the forest. Historical area of use, religious worship and tradition. It is also the area where the king of Doñana is found, the Iberian lynx, this being that has been brought to the brink of extinction and rescued after a long process that continues to this day. One of his “noble titles” is being an “umbrella species”; This means saving countless species since a large amount of land is necessary for their conservation and, therefore, all the diversity of the Doñana’s ecosystems found there will also be protected. Trees, lizards, insects and birds could be said to be protected thanks to the Iberian lynx. ​

Iberian lynx Lynx pardinus

 

Those are some of the values and knowledge that we transmit at DoñanaTour.

 

Thank you and until our next tour with DoñanaTour!

 

Information sources:

Doñana and its crucial location.

Donana is a privileged and unique place due to its ‘strategic’ geographical location. Its physical, biological, ecological, and habitat composition is influenced by its position in the map.

The coastal location of Doñana on the Atlantic Ocean and the mouth of the Guadalquivir River creates a series of aquatic ecosystems. Some of these are coastal lagoons, which are fundamental for wildlife and biodiversity in the region. Furthermore, the interaction between fresh and saltwater in these areas contributes to the formation of unique habitats.

The confluence of the Guadalquivir River with the Atlantic Ocean creates a mosaic of ecosystems, from freshwater marshes to coastal dunes. This interaction of different habitat types favors biological diversity and promotes a complex network of ecological interactions.

Doñana has a Mediterranean climate, characterized by dry and hot summers and mild and humid winters. This seasonal variation in climatic conditions influences the diversity of habitats present in the area, such as marshes, dunes, and forests, and determines which types of species can survive and thrive in the region. It is also very close to the Strait of Gibraltar and, therefore, the Mediterranean waters. In this sense, Doñana is situated between both seas: the Atlantic Ocean and the Mediterranean Sea, in the ‘East-West axis.’

On the other hand, it serves as a connection between Europe and Africa, that is, the ‘North-South axis.’ A warm continent and a cold continent. Doñana’s strategic location between both continents makes it a key point in the migratory bird route. Millions of migratory birds use Doñana as a resting and feeding area during their seasonal journeys. This contributes to the spectacular diversity of birds found in the area.

All these factors give Doñana its most distinctive characteristic compared to other natural spaces: the great diversity of ecosystems and habitats.

This initial framing and presentation of Doñana are part of what we teach in our Environmental Education Programs.

The voices of Autumn

The arrival of wintering birds in Doñana

THE AUTUMN VOICES

Hello World!
From Doñana awaiting the much-desired rains that will flood the marsh, greening the forest and quenching the thirst of life.
And between looks towards a cloudless sky, comes the sound of autumn to Doñana, which is broadcast by hundreds of geese that will turn into thousands, filling the air with their voices and painting the blue sky with their silhouettes in formation. The geese that like every year have been announcing, always, the arrival of autumn rains.
For those who have lived the passage of time in Doñana and have learned to love their landscapes, these birds, which like many others come from the far north, initiate one of the most vibrant seasons of the marsh and fill the heart with a special emotion, that in passion becomes to observe, learn and learn from the rich and diverse winter fauna of Doñana.
But this year the squawking of the geese and the parpar of the anatidae that always accompany them, have not been accompanied by the rains, not even the cold, rather it seemed an arrival of birds in spring but with the characters changed.
These situations of lack of rain and high temperatures in the autumnal months are not new and are even repeated cyclically in the south, although perhaps they are increasingly frequent and intense in terms of dryness and heat.
Even so, the marshes of Doñana are the most important wintering place for geese in Europe, each year hosting more than one hundred thousand specimens. They come mainly from the south of Scandinavia and the Baltic countries, accustomed to wet and flooded areas where they feed on tubers and rhizomes, hence they find in the marshes of Doñana an ideal place to spend the winter that has frozen their northern lands.
It is at dawn, when the screaming of the geese is heard among the mists of the marsh in search of their first meal, the rhizome of the castanet, perennial grass, endowed with a deep system of roots, rhizomes and underground tubers. But in order to better digest these foods the geese begin their morning walk in the dunes of Doñana where they swallow sand and pebbles that in their gizzards will serve to crush better the castanet.
This peculiar custom gives its name, between the complex of mobile dunes, to one of the most emblematic places in Doñana: Cerro de los Ánsares, the ideal place to tell you about the next world!