Posidonia

The recognized ecological importance of Posidonia oceanica, the most important seagrass of the Mediterranean Sea, makes it crucial to assess the state of health of its meadows, discriminating natural from anthropogenic impacts. In this paper, the hydrodynamic conditions at the upper limit of P. oceanica meadows along the Ligurian coast (NW Mediterranean Sea) were investigated. A relationship between the distance of the upper limit of the meadow from the shoreline and the morphodynamic domain of the beach (i.e. distinctive types of beach produced by the topography, wave climate and sediment composition) was found. A zonation of the state of the shallow portions of the meadows down the submerged beach profile was identified. Zone a, from the shoreline to the breaking limit, is naturally critical for the development of the meadow. Zone b, from the breaking limit to the closure depth, is subjected to natural and human impacts. Zone c, below the closure depth, is little influenced by coastal dynamics. This study quantifies for the first time how much the status of the shallow portions of P. oceanica meadows is dependent on coastal dynamics, which is important for their proper management.

In June 2009, ProMare and SBAToscana (Soprintendenza per i Beni Archeologici per la Toscana) carried out an archaeology project near the Island of Capraia, Italy. The project the entailed mapping, recording, and partial excavation of an underwater site that contains ...

"Information on dietary habits of mesograzers in Posidonia oceanica seagrass meadows is scarce and restricted to a few species. Here we provide data on the most likely food sources for eight gastropod species inferred from
stable isotope data. We observed very similar isotopic signals for all species regardless of trophic guild category, indicating similar consumption behaviour with a main diet contribution from epiphytes. We also review the state of knowledge on gastropod-epiphyte-seagrass interactions, with particular emphasis on the scarcity of studies derived from Mediterranean systems. Laboratory experiments showed that under moderately nutrientenriched
conditions, two species of gastropods (Bittium reticulatum and Jujubinus striatus) were controlling epiphyte biomass at high grazer densities, with no consequences for seagrass performance. Finally, the results of a long-term in situ fertilisation experiment showed that the d15N signal for seagrass, epiphytes and gastropods reflects experimentally induced eutrophication, thus cascading up nutrient effects throughout the food web."

In June 2009, ProMare and SBAToscana (Soprintendenza per i Beni Archeologici per la Toscana) carried out an archaeology project near the Island of Capraia, Italy. The project the entailed mapping, recording, and partial excavation of an underwater site that contains artifacts mostly from the second and first centuries BC. General artifact assemblage and distribution indicates a shipwreck in this location, and the analysis of the data collected over a series of seasons of archaeological work contributes to a better understanding of the site as well as the commercial and social history of the island. Capraia is part of the Tuscan Archipelago, off the northwest coast of Italy, between Italian mainland and the north point of Corsica. It is 62 km west of the city of Livorno, and 32 km northwest of the island of Elba. The volcanic island has a surface area of 19 km 2 and its highest point measures 447m above sea level. Settlement is limited to the port area and a small village above it, w...

Exploitation of natural gas from shale, i.e. ‘shale gas’ is very successful in the USA and Canada. Its success has a direct impact on the energy policies throughout the world including Europe. In the Netherlands, shale gas is probably going to be exploited in the near future too. What is shale gas, where does it come from, and how can it be explored and produced? What are the differences with conventional production of natural gas, and what are the hazards and risks for the natural environment and society, such as (drink) water pollution and nuisance for the public living in the surroundings of a production location? These are a few of the issues that are raised in relation to shale gas production and will be addressed in the presentation.

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PRADERAS DE FANEROGAMAS MARINAS EN EL LITORAL ANDALUZ (PDFs)

0 PRADERAS DE FANEROGANAS MARINAS EN EL LITORAL ANDALUZ (436K)
1 PROLOGO (203K)
2 PRESENTACION (96K)
3 INTRODUCCION AL LITORAL ANDALUZ (1521K)
4 GENERALIDADES DE LAS FANEROGANAS MARINAS (2914K)
5 ZONAS DE DISTRIBUCION Y LOCALIZACION DE FANEROGANAS MARINAS (442K)
6 IMPORTANCIA DE LAS PRADERAS DE FANEROGANAS MARINAS (338K)
7 GRUPOS BIOLOGICOS ASOCIADOS (3860K)
8 APLICACIONES TRADICIONALES DE LA POSIDONIA (427K)
9 PROBLEMATICA AMBIENTAL Y REGRESION DE LAS PRADERAS MARINAS (1764K)
10 GLOSARIO (190K)
11 BIBLIOGRAFIA (106K)