Influence of shellfish farming activities on nitrification, nitrate reduction to ammonium and denitrification at the water-sediment interface of the Thau lagoon, France

The seasonal patterns of nitrification, denitrification and dissimilatory ammonium production (DAP) rates were studied in the sediment of 2 stations in the Thau lagoon (south of France). The station ZA was located within the shellfish farming zone and thestation B was the reference site. A marked effect of shellfish farming on bacterial activities was observed. Spatial differences were associated with discrepancies in the organic content and the reduction state of sediments, i.e. highest reductive processes (denitrification and DAP) were noted in shellfish farming area, whereas the oxidative process (nitrification) was predominant outside the farming zone. At both stations, the DAP activity increased in September (autumn) concomitant with an increase of the C/N ratio in the sediment due to the sedimentation of the summer phytoplanktonic production. Nitrification and denitrification rates exhibited maxima in November (winter) corresponding to dissolved inorganic nitrogen inputs from the surrounding land. In the shellfish farming site, 98% of nitrate was reduced to NH4+ and 2% to N2O, showing that the most of the NO3- was reduced to ammonium and remained available for the ecosystem

Roger Williams University Course Will Equip Shellfish Farmers

Non-credit course will teach basic shellfish farming theory and technique

Benthic macrofauna and sediment reworking quantification in contrasted environments in the Thau Lagoon

As part of the Microbent-PNEC Program: ‘‘Biogeochemical processes at the wateresediment interface in eutrophicated environment’’, the aim of this work was to specifically investigate and quantify the relationships between macrobenthos and sediment reworking in the Thau Lagoon in order to provide information on the potential contaminant distribution and movements at the wateresediment interface. In order to achieve this, three cores were sampled at two stations (in the central part of the Thau Lagoon and near the shellfish farming zone) in the Thau Lagoon, in December 2001, April 2002, August 2002, January 2003 and May 2003. On the basis of quantification of macrobenthos and sediment reworking, evidence is provided of: (1) similar sediment mixing intensities for different species composition at the two stations; (2) the major role of functional bioturbation groups (e.g., biodiffusors and gallery-diffusors) modulated by seasonal variability on sediment mixing; (3) an increase of intensity in summer suggesting potentially different patterns of redistribution, bioaccumulation and chemical fate (e.g., speciation) of deposited contaminants

Risk Perceptions and Risk Management Strategies in French Oyster Farming

The article analyses risk perception in shellfish farming as well as farmers' willingness to rely on coverage mechanisms. Factor and econometric analyses (logit and ordered multinomial logit models) have shown that a number of socio-economic factors specific to farmers and their businesses contribute to defining their degree of risk perception and reliance on management tools. Beyond the conventional self-protective mechanisms, the study will focus on farmers' willingness to rely on risk-transfer mechanisms that the market has so far failed to provide.Shellfish farmers, risk perception, logit and ordered multinomial logit models, factor analyses, coverage instruments

Disastro ambientale nel Mar Piccolo di Taranto durante la Prima Guerra Mondiale

Since 1883, the Mar Piccolo of Taranto (Ionian Sea, Mediterranean) has played a dual role as privileged area for shellfish farming and strategic military port. This historical research, based on the collection of direct, indirect and iconographic sources, provided socioeconomic information about Taranto from 1883 to 1926 and unprecedented data on the most probable catastrophic effects (the sinking of a dreadnought) on the marine environment during the First World War. The analysis of original documents showed that the strategies (scientific studies, application and propagation of best practices; economic evaluation of productions; communication with military and civil authorities and shellfish farmers) adopted by Attilio Cerruti (the Marine Biology Laboratory’s Inspector) ensured shellfish farming survival and its recovery in the post war period. Moreover, Cerruti’s holistic approach could be a useful example for the solution of current management and conservation problems related to goods and services of valuable ecosystems highly impacted by human activities (not limited to warfare), such as those affecting the Mar Piccolo of Taranto