Veta la Palma



History
Covering an area of some 28,000 acres, the Veta la Palma estate is located in the municipality of Puebla del Río (Seville) and occupies nearly half of the southern part of the Isla Mayor area of the Guadalquivir. It also borders the river Guadiamar or Brazo de la Torre and is within the Doñana Nature Reserve.  Isla Mayor, as the nerve center of the marshlands on the Guadalquivir, has seen a long process of transformation over time due to both the natural evolution caused by silting and the effects of human activity. 
The first attempts to exploit the resources of the Isla date back to the 19th century, but it was not until the third decade of the 20th century that farming really began in the area, thanks to a comprehensive project carried out between 1926 and 1928 by the British company Islas del Río Guadalquivir Limited.
During the 1940s and 50s, the cultivation of rice became the main economic activity on the Isla Mayor del Guadalquivir, with rice fields occupying the northern half of the island (35,000 acres). In the southern part, however, extensive livestock farming in the fields owned by the Veta la Palma estate was the main activity until the end of the 1970s. 
In 1982, the Empresa Agropecuaria del Guadalquivir, owner of the estate since 1966, was acquired by the Hisparroz, S.A. group, which transformed it into Pesquerías Isla Mayor, S.A. (PIMSA).  After a brief introductory period, in 1990 PIMSA was authorized by General Directorate for Fisheries of the Andalusian Regional Government, following the Sector Plan for the Use and Management of the Doñana National Park (PRUG), to introduce fish farming to the area. Initially using 600 hectares of the estate, the project was gradually extended to reach 8,000 acres. These are flooded with high-quality waters which provide a habitat to the significant population of fish and crustaceans which are reared on the farm. A further 8,000 acres are currently dedicated to dry crops and 1,000 acres to the cultivation of rice. The remaining 12,000 are maintained to preserve the original biotope of the marshlands. 
Today, Veta la Palma is a fine example of integrated intervention, whereby the creation of an artificial wetland habitat for fish farming and the interaction of this process with other activities on the estate, have enhanced the environmental quality of the area, whilst generating new economic and conservation values based on principles of sustainability. 
Ecology
The fish farming activities carried out on the estate offer a series of environmental benefits for the hydrology and ecology of the marshlands of the Guadalquivir. Extensive and semi-extensive fish farming has attracted a range of nesting and migratory species of birds. 
The total bird population of Veta la Palma can reach a figure of 600,000 covering some 250 different species, of which more than 50 suffer some degree of threat in other areas. As such, the artificial wetland habitat created on the estate plays an essential part in the conservation of European birds by guaranteeing food both for the species which complete their development cycle from birth on the island before migrating, and those which, during the course of migration between Africa and Europe, stay in the area temporarily to find food.
The extensive farming ponds are characterized by their stability in terms of the area flooded (8000 acres), depth (40-50 cm), renovation level (1 hm3/day in summer) and salt content. 
This helps to reduce the impact of changes in the levels of salt content and water as well as the concentration of nutrients in the estuary, thereby contributing to a massive development of micro-algae which are capable of assimilating the excessive amounts of nitrogen and phosphorus in the water. 
In this way, the water from Veta la Palma which is returned to the river is of exceptional quality in terms of its physical and microbiological properties. Furthermore, the creation of more than 100 islands in the ponds for the nesting of waterfowl together with the revegetation of 93 miles of banks, have improved the landscape of the estate considerably. The artificially flooded areas also play a vital role in the protection of the natural fish population of the estuary of the Guadalquivir itself including migratory species such as the common eel (Anguilla anguilla) or striped mullet (Mugil cephalus), and other species which complete part of their natural cycle in the estuary such as sole (Solea solea, S. senegalensis), maegre (Argyrosomus regius), or sea bass (Dicentrarchus labrax), as well as marine species  such as the black sea anchovy (Engraulis encrasicholus) or wedge sole (Dicologoglossa cuneata).  
In a study carried out by the Doñana Biological Station, it was noted that “…to preserve the abundance and diversity of waterfowl in Doñana, it is obvious that it is necessary to manage areas such as Veta la Palma which can provide high food biomass (invertebrates and macrophytes) for birds”.  
Veta la Palma is part of both the Doñana Biosphere Reserve and the Natura 2000 Network and has been designated a RAMSAR site of international importance.
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