News

The 6th IUFRO Conference on Phytophthora in Forest and Natural Ecosystems will take place in 2012 at Córdoba Univ. (Spain)....

Clive Brasier interviewed by Europa Press....

The Natural Environmental Research Council (NERC) from the UK comments on the Pajarera Project...

WWF-Spain includes Cork oak in the top-ten list of most endagered species....

espatula_pajarera(c) Héctor Garrido

Interesting Information

The History of Las Pajareras de Doñana

'Las Pajareras' live

Obituary of centenarian oaks

Newspaper Library

Funding Sources

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The decline of cork oak forests in the Doñana National Park

The cork oak forest in the ecotone between the saltmarshes and the sand dunes in the Doñana National Park is one of the remnants of the forests which formerly dominated wide extensions within this World Heritage Site. This population of centenarian Quercus suber (locally known as Las Pajareras - The Bird Site-) was devasted by human explotation during the 17th to 20th centuries, and is still affected by the low regeneration rates. Nowadays, the population is also threathened by the presence of large colonies of protected tree-nesting wading birds in those areas adjancent to the saltmarshers ("La Vera"), and by the action of pathogenic oomycetes.

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The establishment of those colonies of tree-nesting wading birds on these centenarian oaks seems to be related to the mortality of these trees. The birds transport huge amounts of materials from broad feeding areas to reduced nesting sites. Thus, nesting sites may be affected by large inputs of nutrients and other allochthonous compounds, which has a high impact in the ecosystem.

Nowadays, two species of pathogenic oomycetes negatively affect the cork oaks in the Doñana National Park: Phytophthora cinnamomi and Pythium spiculum. The former species experienced a large expansion in the area in 2010, when the winter and the spring seasons were exceptionally humid. In this cork oak forest, there is a direct relationship between P. cinnamomi infection and tree decay and death.

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The Pajarera Project

This is a multidisciplinar research project that aims to analise the impact of the nesting of wading-birds in the cork oak forest in the Doñana National Park.

We aim to analyse the impact of the bird colonies on different components and processes of the ecosystem, with both experimental and observational approaches:

- soil chemical composition and nutrient cycling

- physiological status of the cork oak trees

- biological interactions at the root level (mycorrhizae, pathogens)

- growth and survival of oak seedlings

This objetives are also studied in other oak forest that are not affected by bird colonies

Click here for a detailed description of the research objectives.

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