Tracing the flow of organic matter from primary producers to filter feeders in Ria Formosa lagoon, Southern Portugal

Abstract In the 80ies, in Southern Europe and in particular in Ria Formosa there was an episode of heavy mortality of the economically relevant clam Ruditapes (R.) decussatus associated with a debilitating disease (Perkinsosis) caused by Perkinsus olseni. This protozoan parasite was poorly known concerning its’ differential transcriptome in response to its host, R. decussatus. This laboratory available protozoan system was used to identify parasite genes related to host interaction. Beyond the application of molecular biology technologies and methodologies, only the help of Bioinformatics tools allowed to analyze the results of the study. The strategy started with SSH technique, allowing the identification of parasite up-regulated genes in response to its natural host, then a macroarray was constructed and hybridized to characterize the parasite genes expression when exposed to bivalves hemolymph from permissive host (R. decussatus), resistant host (R. philippinarum) and non permissive bivalve (Donax trunculus) that cohabit in the same or adjacent habitats in Southern Portugal. Genes and respective peptides full molecular characterization depended on several Bioinformatic tools application. Also a new Bioinformatic tool was developed.

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Occurrence and characterization of pearls from oysters of the genus Crassostrea

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315416000382 ◽

2016 ◽

Vol 97 (2) ◽

pp. 297-302

Author(s):

Frederico M. Batista ◽

Ana Grade ◽

Deborah M. Power ◽

Francisco Ruano ◽

Elizabeth M. Harper

Keyword(s):

Oyster Shell ◽

X Ray Diffraction ◽

Parasitic Copepods ◽

Ria Formosa ◽

Crassostrea Angulata ◽

Mollusc Species ◽

Southern Portugal ◽

Foot Disease ◽

The Right ◽

Almost All

The occurrence of pearls in the ‘true’ oysters, the Ostreioidea, is poorly documented despite being the most produced mollusc species in the world. Oysters of the Crassostrea genus were collected in two different sites in southern Portugal where both Crassostrea angulata and C. gigas are present, namely in: (1) the Ria Formosa lagoon where pearls were not observed (N = 446); and (2) the Guadiana estuary where pearls were found in 12 out of the 798 oysters analysed. The pearls were located mainly at the edge of the right mantle lobe in the inhalant chamber and their maximum length ranged from 0.9 to 5.5 mm. Almost all the pearls had a white-cream colouration with the exception of two pearls that had a black-brown colour. X-ray diffraction analysis of one pearl showed that it was entirely calcitic with no traces of either aragonite or vaterite. The pearls observed were therefore non-nacreous pearls. Scanning electron microscopy (SEM) revealed a diversity of microstructures including prismatic, foliae-like sheets and blocky textures, i.e. highly reminiscent of the host oyster shell microstructures. Parasites (e.g. parasitic copepods, Haplosporidium-like plasmodia) and signs of diseases (e.g. foot disease) were observed in some of the oysters analysed, but they were not associated with the occurrence of pearls. The present work is one of the few studies on the occurrence of natural pearls in ‘true’ oysters and to our knowledge the first description of their microstructure by SEM.

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Sources of organic matter in Ria Formosa revealed by stable isotope analysis

Acta Oecologica ◽

10.1016/s1146-609x(99)00122-8 ◽

1999 ◽

Vol 20 (4) ◽

pp. 463-469 ◽

Cited By ~ 27

Author(s):

Raquel Machás ◽

Rui Santos

Keyword(s):

Organic Matter ◽

Stable Isotope ◽

Stable Isotope Analysis ◽

Isotope Analysis ◽

Ria Formosa

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Discerning natural and anthropogenic organic matter inputs to salt marsh sediments of Ria Formosa lagoon (South Portugal)

Environmental Science and Pollution Research ◽

10.1007/s11356-020-09235-9 ◽

2020 ◽

Vol 27 (23) ◽

pp. 28962-28985

Author(s):

Mukesh Kumar ◽

Tomasz Boski ◽

Francisco J. González-Vila ◽

José Mª de la Rosa ◽

José A. González-Pérez

Keyword(s):

Organic Matter ◽

Salt Marsh ◽

Ria Formosa ◽

Marsh Sediments ◽

Salt Marsh Sediments ◽

South Portugal

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Molecular fossils inferring Quaternary sea-level changes

10.5194/egusphere-egu2020-7153 ◽

2020 ◽

Author(s):

Martina Conti ◽

Martin Bates ◽

Natasha Barlow ◽

Richard Preece ◽

Kirsty Penkman ◽

...

Keyword(s):

Organic Matter ◽

Sea Level ◽

Sea Level Change ◽

Sea Level Changes ◽

Primary Producers ◽

Chlorophyll Pigments ◽

Molecular Fossils ◽

Level Change ◽

Targeted Analysis ◽

The Impact

Targeted analysis of organic matter in soils and sediments is useful for evaluating past environmental conditions, as specific compounds may be directly linked to organisms and hence to the conditions in which they inhabited the environment.&#160; Variations in molecular fossil distributions have become a powerful tool for understanding changes in palaeoclimate conditions.&#160; This work uses molecular fossils to give an insight into the impact of transgressive events on primary producers inhabiting the studied basin, and hence a more detailed record of sea-level change.The cores studied consisted of unconsolidated immature sediments from the mid-late Pleistocene (< 500,000 years) and the Holocene. &#160;Molecular fossils, such as chlorophyll pigments and lipids, exhibit fluctuations as a response to changes in palaeoenvironmental conditions, providing a useful marker for sea-level changes. &#160;Fluctuations in the pigment and n-alkane distribution reflect changes in primary producer activity, while the GDGT-based index of branched and isoprenoid tetraether lipids (BIT) differentiates between terrigenous and marine organic matter inputs. &#160;Lipids were analysed by GC-FID and HPLC-MS while analysis of chlorophyll pigments was carried out using a new UHPLC-DAD method.The results from biomarker analyses show excellent time-resolved agreement with previous lithological and ecological studies, but enabled a more sensitive response of different primary producers to changing conditions to be observed. &#160;The molecular fossils were able to detect the onset and cessation of the studied transgressions earlier than it was possible with microfossil evidence.&#160; Linking the pigment and lipid record with more secure dating will enable a more accurate record of Quaternary relative sea-level change.

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Morphometric relationships and relative growth of Hexaplex trunculus and Bolinus brandaris (Gastropoda: Muricidae) from the Ria Formosa lagoon (southern Portugal)

Journal of the Marine Biological Association of the United Kingdom ◽

10.1017/s0025315415001472 ◽

2015 ◽

Vol 96 (7) ◽

pp. 1417-1425 ◽

Cited By ~ 6

Author(s):

Paulo Vasconcelos ◽

Carlos M. Barroso ◽

Miguel B. Gaspar

Keyword(s):

Shell Length ◽

Morphological Plasticity ◽

Shell Shape ◽

Shell Weight ◽

Geometric Morphometric ◽

Relative Growth ◽

Ria Formosa ◽

Hexaplex Trunculus ◽

Southern Portugal ◽

Bolinus Brandaris

The present study reports morphometric relationships and discusses the relative growth in the banded murex (Hexaplex trunculus) and the purple dye murex (Bolinus brandaris) from the Ria Formosa lagoon (southern Portugal). A total of 11 morphometric parameters (eight linear variables: shell length, shell width, total aperture length, aperture length, aperture width, spire length, spire width and siphonal canal length; three ponderal variables: total weight, soft parts weight and shell weight) were analysed in both species. The analyses comprised numerous individuals of both sexes and with broad size ranges (H. trunculus: 10.7–82.8 mm shell length; B. brandaris: 14.6–107.7 mm shell length), fairly representative of the populations from the Ria Formosa lagoon. In general, B. brandaris exhibited greater morphological plasticity and higher variability in shell shape compared with H. trunculus. In both species, the vast majority of morphometric relationships displayed positive allometries, distantly followed by negative allometries and by isometries. Although H. trunculus and B. brandaris are known to lack external sexual dimorphism, several morphometric relationships revealed significant differences in the type of growth between sexes, which should be further confirmed using more powerful techniques, such as geometric morphometric analyses of shell shape.

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