Cap Ferrat Research Articles

Microplastic load and polymer type composition in European rocky intertidal snails: Consistency across locations, wave exposure and years

Microplastics (<5 mm) are emerging pollutants in oceans worldwide. As such small particles are easily ingested, microplastics are found in numerous pelagic and benthic organisms. However, information on microplastics in rocky intertidal organisms and habitats is relatively scant. Therefore, we examined snails and water samples from wave-sheltered and wave-exposed rocky intertidal habitats in Helgoland (North Sea), Cap Ferrat and Giglio (Mediterranean) and Madeira (Atlantic Ocean) in 2019–2020 for microplastics. Furthermore, we examined snails from the same habitats in Helgoland, Cap Ferrat and Giglio in 2007–2009. In total, we performed 362 individual micro-Fourier-transform infrared spectroscopy (μFTIR) measurements on the snails and water samples. While the snails contained 50 microplastics (composed of nine polymer types), the water samples contained 24 microplastics (comprising six polymer types). Microplastic load and polymer type composition in the snails were rather similar across locations, wave exposure and years. Also, microplastic load and polymer composition in the water samples were similar across locations and wave exposure. Moreover, snail and water microplastic loads were significantly correlated which indicates that snails are useful bioindicators for microplastic loads in rocky intertidal habitats. Interestingly, the majority of the microplastics consisted of paint chips that likely derived from ships. Overall, our study provides the first comprehensive microplastic record in rocky intertidal organisms across locations, wave exposure and years that can serve as a baseline to examine historic and future microplastic dynamics in rocky intertidal systems.

High-resolution coastal hazard assessment along the French Riviera from co-seismic tsunamis generated in the Ligurian fault system

The French Riviera is a densely populated and touristic coast. It is also one of the most seismically active areas of the Western Mediterranean. This is evidenced by the Mw 6.7–6.9, 1887 earthquake and tsunami, that was triggered nearshore, rupturing the easternmost 40 km of the 80-km-long Ligurian fault system, which runs parallel to and offshore of the Riviera. Here, coastal hazard from co-seismic tsunamis is assessed along the French and part of the Italian Riviera by simulating three Ligurian earthquake scenarios: (1) the 1887 event offshore Genoa, Italy; (2) a similar event transposed to the westernmost 40-km segment of the fault, offshore Nice, France; and (3) the rupture of the entire 80-km fault, which constitutes an extreme case scenario for the region. Simulations of tsunami propagation and coastal impact are performed by one-way coupling with the Boussinesq model FUNWAVE-TVD, in a series of nested grids, using new high-resolution bathymetric and topographic data. Results obtained in 10-m coastal grids provide the highest resolution predictions to date for this section of the French Riviera of co-seismic tsunami coastal hazard, in terms of inundation, runup, and current velocity. In general, the most impacted areas are bays (near Cap d’Antibes and Cap Ferrat), due to wave buildup and shoaling within semi-enclosed shallow areas, enhanced by possible resonances. In contrast to earlier work, which was based on coarser resolution grids, the area of Nice harbor is found to be rather well sheltered. It should be noted that uniform fault slip was used in the ruptures and runup estimates could locally be enhanced in case of more complex ruptures, such as segmented and heterogeneous ruptures.

Diabetes, Obesity and Metabolism

Diabetes, Obesity and MetabolismVolume 19, Issue S1 p. 1-2 ISSUE INFORMATIONFree Access Diabetes, Obesity and Metabolism First published: 07 September 2017 https://doi.org/10.1111/dom.13032AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume19, IssueS1Supplement: β-Cell Signalling Revisited. Proceedings of the 18th Servier-IGIS Symposium, St Jean Cap Ferrat, France, 23–26 March 2017September 2017Pages 1-2 RelatedInformation

Diabetes, Obesity and Metabolism

Diabetes, Obesity and MetabolismVolume 18, Issue S1 p. 1-2 ISSUE INFORMATIONFree Access Diabetes, Obesity and Metabolism First published: 12 September 2016 https://doi.org/10.1111/dom.12755Citations: 1AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article.Citing Literature Volume18, IssueS1Supplement: A Change of Personality: Dedifferentiation and Transdifferentiation in β-Cells. Proceedings of the 17th Servier-IGIS Symposium, St Jean Cap Ferrat, France, 7–10 April 2016September 2016Pages 1-2 RelatedInformation

Atmospheric input of inorganic nitrogen and phosphorus to the Ligurian Sea: Data from the Cap Ferrat coastal time-series station

Atmospheric fluxes of bio-available inorganic nitrogen (DIN, i.e. nitrate+ammonium) and phosphorus (DIP, i.e. phosphate) were measured in 2010, 2011 and 2013 at the sampling station of Cap Ferrat (Ligurian Sea). Wet and dry fluxes of DIN, averaged over three years, were 35 and 19mmolm−2yr−1, respectively. Most of the nitrate was deposited under dry form, whilst ammonia was twice more found in wet deposition. Wet and dry fluxes of DIP, averaged over three years, were 0.11 and 0.64mmolm−2yr−1, respectively. Atmospheric fluxes of DIN and DIP were compared with other photic zone nutrient input sources, physical and biological, i.e. winter convection, N2 fixation, and upward diffusion. Even if convection is by far the most important nutrient input for surface waters, atmospheric sources may be the second one, supplying more nutrients than diazotrophy and diffusion, particularly in conditions of water column stratification.

Statistical distributions of trace metal concentrations in the northwestern Mediterranean atmospheric aerosol

The concentrations of 11 crustal and anthropogenic trace metals (Li, Al, V, Mn, Fe, Co, Ni, Cu, Zn, Cd, Pb) were measured from 2006 to 2008 in the atmospheric aerosol at a northwestern Mediterranean coast (station of Cap Ferrat, situated on the southeastern coast of France). Statistical models (lognormal, Weibull, and gamma) that best represented the trace metal distribution for this environment are described. The lognormal model was selected for the distributions of (in decreasing strength of the fit) Al, Co, Li, Zn, Mn, Cu, Pb, and Cd, i.e., metals that are introduced into the atmospheric aerosol by pulses inducing temporal variability in their concentrations. The gamma model was associated with Fe, i.e., metals that exhibit less inter-annual variability than the former trace metals. The third mode (Weibull) represented the distribution of the concentrations of V and Ni. The statistical approach presented in this study contributed to better define and constrain the distribution of the 11 trace metals of the atmospheric aerosol from the northwestern Mediterranean coast. In a close future, knowledge of these statistical distributions will allow using convolution models to separate their natural and anthropogenic contributions, therefore increasing our ability to study anthropogenic emissions of trace metals and their impact on the environment.

Keyword index

Diabetes, Obesity and MetabolismVolume 14, Issue s3 p. 167-167 KEYWORD INDEX Keyword index First published: 28 August 2012 https://doi.org/10.1111/j.1463-1326.2012.01694.xRead the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinkedInRedditWechat No abstract is available for this article. Volume14, Issues3Supplement: The Hyperstimulated β-Cell: Prelude to Diabetes? Proceedings of the 13th Servier-IGIS Symposium, St Jean Cap Ferrat, France, 15–18 March 2012October 2012Pages 167-167 RelatedInformation

Trace metal concentrations in the North-western Mediterranean atmospheric aerosol between 1986 and 2008: Seasonal patterns and decadal trends

Climatic and anthropogenic changes are able to engender modifications in the aerosol composition at different geographical and temporal scales. The present study addresses this question for the trace metal concentrations (TM = Al, Fe, Mn, Co, Ni, Cu, Pb, Cd and Zn) of aerosol from the North-western Mediterranean coast of France (Cap Ferrat, nearby Nice) between 1986 and 2008. From seasonal variations (2006–08) and decadal trends (1986–2008) of TM concentrations, three groups of elements can be distinguished. They consist of different aerosol sources: crustal-derived elements (Al, Fe, Mn and Co), trace metals of anthropogenic origin (Pb, Cd and Zn) and a third, intermediate, group of trace metals that presented both anthropogenic and natural/crustal influences (Ni and Cu). Reproducible seasonal patterns were observed for crustal and intermediate elements with highest concentrations between May and November, while anthropogenic trace metals did not show a pronounced seasonal cycle. Nevertheless, highest concentrations of anthropogenic trace metals occurred mostly in autumn/winter. Aerosol concentrations of anthropogenic TMs decreased remarkably over the last two decades, while crustal trace metals did not show any evolution. Nickel and copper aerosol concentrations remained constant, as well. Lead concentrations decreased from 1986 (29.34 ng m − 3 ) to 2008 (3.33 ng m − 3 ), overall by 90%. Cadmium and zinc aerosol concentrations decreased by 66 and 54%, respectively, between 1998 and 2006–08, from 0.27 to 0.09 ng m − 3 and from 23.9 to 10.9 ng m − 3 , respectively. These findings demonstrate the response of the atmospheric environment to the implementation of antipollution policies. Possible changes of trace metal emissions sources and local influences are discussed.

First Report of Cucumber mosaic virus in Echium candicans in France.

Echium candicans (Linn.) Herb. Banks (Pride of Madeira or Viper's Bugloss), family Boraginaceae, is a perennial shrub used in gardens for the ornamental quality of its deep blue inflorescences, especially in coastal areas near the Mediterranean Sea. Mosaic symptoms were observed in leaves of E. candicans in the Alpes Maritimes Department of southeastern France, St Jean Cap Ferrat in 1994, Menton in 2002, and Antibes in 2005. Symptoms exhibited in a range of inoculated plants including Nicotiana tabacum cvs. Xanthi and Samsun, Chenopodium quinoa, C. amaranticolor, Vigna unguiculata cv. Black, and Cucumis sativus cv. Poinsett were typical of Cucumber mosaic virus (CMV). Occurrence of CMV in one sample from each of the three localities was confirmed by the observation of isometric particles (approximately 30 nm) with the electron microscope in crude sap preparations from the infected plants, positive reactions in double-antibody sandwich (DAS)-ELISA to polyclonal antibodies raised against CMV (1), and the nonpersistent transmission of the virus from infected Xanthi to virus-free Xanthi plants by Myzus persicae. In double-immunodiffusion analysis, the three isolates were shown to belong to the CMV subgroup II (1,2). To determine if CMV was responsible for the symptoms observed, the isolate from Antibes was multiplied in Xanthi plants after isolation from local lesions on V. unguiculata and mechanically inoculated to 3-year-old plants of E. candicans tested to be free from CMV before the mechanical inoculation. One month after inoculation, mild mosaic symptoms were observed in young leaves and CMV was detected by DAS-ELISA in 10 of 10 inoculated plants. To our knowledge, this is the first report of CMV in E. candicans.

Of mighty mice and diabetic men: animal models of islet dysfunction

Of mighty mice and diabetic men: animal models of islet dysfunction

Editorial

Although it is clear that β-cell pathology, in particular disordered insulin secretion, is a key underlying pathogenetic feature of most forms of diabetes, complex interactions of the islets with other organs, such as brain, liver, gut, and several peripheral tissues, are also essential for the normal integration of metabolism. It is this area that has been explored in the Seventh Annual Servier-IGIS Meeting, which was held last Spring in St. Jean Cap Ferrat in Southern France. The focus of these meetings, since their inception in 2000, has been the β-cell and the mechanisms underlying its development and function as the source of insulin, the most essential regulator of the blood glucose level. The familiar pathways of glucose, lipid, and amino acid metabolism in humans and other mammals are, of course, fundamental to almost all organisms, except perhaps for the most highly specialized bacteria, so it is not surprising that insulin-like molecules and the insulin/IGF receptor signaling system are well conserved features of all metazoans that have been studied. With the rise of multicellular organisms in evolution came the need to regulate and coordinate metabolism and growth in order to maintain both the constancy of the internal environment (homeostasis) and also to respond to the external environment. One of the most prominent environmental stimuli had to be the availability of nutrients and fuels for survival and growth. The insulin-like hormones, insulin and IGF, appear to have evolved, along with a panoply of other regulatory substances, to fine-tune the efficient uptake, storage, and utilization of nutrients for either energy production or growth. Appropriately, the symposium opened with an introductory lecture by Leopold, reviewing our current knowledge of the control of metabolism and growth in the fruit fly, Drosophila melanogaster , by insulin-like peptides and an insulin signaling pathway that is remarkably similar …

Editorial

Insulin secretion and β-cell biology are the main theme of the Servier-IGIS Meetings that have been held yearly since 2000 in St. Jean Cap Ferrat in southern France (1–5). Previous symposia have mostly focused on insulin secretion and its relationship with β-cell defects in type 2 diabetes. Type 1 diabetes has not previously been considered, since it is generally viewed exclusively as an autoimmune disease. However, the pathophysiology of either disease is centered on β-cells, and type 1 and type 2 diabetes share many concerns, especially the goal of preserving or restoring a normal functional β-cell mass. Evidence has accumulated that immune tolerance reflects a permanent cross talk between the different cells involved in immune survey functions and peripheral tissues, as in the case of β-cells in type 1 diabetes. As in most common autoimmune diseases, the problem of the antigenic specificity of the autoimmune reaction that drives the β-cell damage has been one with most unpredictable issues over the past 20 years. Whether the activation of autoimmunity proceeds from intrinsic immune dysregulation or requires the presence of β-cells is now no longer a question. Against all predictions, the search for the “diabetes autoantigen” has resulted in a long list of candidates with rather loose identification criteria. All presently high-ranking β-cell autoantigens are defined as proteins expressed by β-cells, not as β-cell–specific antigens. Indeed, evidence has accumulated to indicate that B- and T-cells recognize many autoantigens, rather than a single autoantigen, during diabetes development and that most autoantigens are not β-cell specific. This makes type 1 diabetes a β-cell disease rather than an antigen-specific immune disease. As for type 2 diabetes, there is overwhelming evidence that it cannot be considered exclusively from the angle of the β-cell. β-Cells are at the center of multiple physiological loops that send …

Atmospheric input of dissolved inorganic phosphorus and silicon to the coastal northwestern Mediterranean Sea: Fluxes, variability and possible impact on phytoplankton dynamics

One hundred twelve rainwater samples collected from 1986 to 2003 at the signal station of Cap Ferrat (France, NW Mediterranean coast) were analysed for phosphate and silicate contents. This sampling site is affected by a European urban-dominated background material, with episodic Saharan dust inputs. The input of dissolved inorganic phosphorus (DIP) and dissolved inorganic silicon (DISi) was calculated. The most significant loadings of DIP and DISi were selected in order to assess their potential impact on phytoplankton dynamics, particularly in oligotrophic conditions, when surface waters are nutrient-depleted. The theoretical new production triggered by DIP and DISi inputs (NP atmo) was estimated through Redfield calculations. The maximum theoretical DIP-triggered NP atmo was up to 670 mg C m −2 in October, at the end of the oligotrophic period (135 mg C m −3 in the 5 m-thick surface layer). During the same period, the daily integrated primary production measured at the DYFAMED site (NW Mediterranean Sea) was on average 219 mg C m −2 d −1 within the 0–100 m depth water column, while the mean daily primary production in the 5 m-thick surface layer was 1.6 mg C m −3 d −1. However, high NP atmo due to high DIP inputs might be episodically limited by lower DISi inputs, which may consequently lead to episodic preferential growth of non-siliceous phytoplanktonic species.

Current role and future perspectives for ifosfamide in the treatment of malignant non-Hodgkin’s lymphoma—resultsfrom an expert meeting

In this supplemental issue of Annals of Oncology, leading experts from Australia, Europe and the USA present results from their trials using ifosfamide-containing chemotherapy regimens for the treatment of malignant non-Hodgkin’s lymphoma (NHL) and Hodgkin’s disease (HD). The relative merits of the established regimens, achievable treatment results and future perspectives for ifosfamide regimens were discussed during a workshop, held in October 2002 at Cap Ferrat, France. The expert faculty discussed practical issues related to the use of ifosfamide and mesna including suggestions for inpatient and outpatient ifosfamide regimens in combination with rituximab and guidelines for the management of possible side-effects. The practical guidelines for outpatient ifosfamide-based regimens, by fractionating the administration of ifosfamide, infusomates or oral mesna, were discussed as well. Many patients with aggressive NHL can be cured with anthracycline-containing chemotherapy regimens. The benefit of adding rituximab to cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) chemotherapy for non-pretreated elderly patients with aggressive NHL was demonstrated in a recently published randomized trial performed by Groupe d’Etude des Lymphomes de l’Adulte (GELA) [1]. Despite this, more than half of the patients are primarily refractory or relapse and require salvage therapy. A certain subset of patients with chemosensitive disease can be cured with high-dose therapy and stem cell transplantation. Before high-dose therapy, patients usually receive combination chemotherapy regimens to establish tumor chemosensitivity and to reduce tumor bulk. It is critical that a cytoreductive regimen has a high response rate with minimal organ-related toxicities, while at the same time providing adequate collection of peripheral blood stem cells (PBSC).

First Report of Cucumber mosaic virus in Teucrium fruticans.

Teucrium fruticans (shrubby germander), family Lamiaceae, is a hardy shrub. Being drought tolerant, it is widespread in the Mediterranean area. Because it is readily propagated through cuttings, it is also planted in hedges. In 1997 and 2000, respectively, yellow chlorotic areas were observed on the foliage of T. fruticans in Saint Jean Cap Ferrat (France) and San Remo (Italy). These symptoms were distinct from those produced by a rust that frequently affects T. fruticans in these areas. Viruses from both locations were identified as Cucumber mosaic virus (CMV) based on the following: (i) symptoms after mechanical inoculation of Nicotiana tabacum cv. Xanthi nc, N. tabacum cv. Samsum, Chenopodium quinoa, C. amaranticolor, Vigna unguiculata cv. Black, and Cucumis sativus cv. Poinsett; (ii) the morphology of particles observed in electron microscopy of uranyl acetate stained leaf dips from tobacco; and (iii) positive result from leaves of diseased T. fruticans and mechanically inoculated host plants cited above based on enzyme-linked immunosorbent assay (ELISA) using CMV antisera. On tobacco cv. Xanthi nc, the French (F) and Italian (I) isolates first induced essentially necrotic rings on the inoculated leaves followed by the same systemic symptoms as described above. The two isolates were cloned from local lesions after two successive inoculations in V. unguiculata cv. Black, multiplied in tobacco, purified with the citrate-chloroform method, and stabilized with formaldehyde (1). The serotype determination was made by double immunodiffusion in agar gel with the CMV-D and CMV-To strains and homologous antisera (1,2). The formation of spurs and antigen-antibody lines indicated that both isolates belonged to the ToRS serotype (1). Thirty plants of T. fruticans cv. Azureum, first tested negative for CMV using ELISA, were mechanically inoculated with the F isolate (25 plants) and the CMV-D strain (five plants) and cultivated in a hydroponic system. Three months later, plants inoculated with the F isolate were positive for CMV using ELISA and displayed clear symptoms with chlorotic spots, which were sometimes ring-shaped. As plants mature, symptoms tend to disappear on young shoots. For the CMV-D strain, three plants of five were ELISA positive, but did not show any typical symptoms. This report demonstrates the infection of T. fruticans by CMV and the symptom induction by some CMV isolates. In September 2002, two CMV isolates were collected from T. fruticans in public gardens in Menton (France) and Genoa (Italy). These new isolates have the same characteristics as those described in this report.

Atmospheric deposition of metallic pollutants over the Ligurian Sea: labile and residual inputs

Atmospheric fluxes of six trace metals (Cd, Cr, Cu, Ni, Pb and Zn) with Al as a crustal reference were measured at Cap Ferrat (French Riviera) between February 1997 and July 1998. An original sampling protocol enabled the separation of labile (seawater at pH 2) and residual fractions in the total atmospheric input. Median acid-labile fractions were 91%, 69%, 83%, 84%, 97% and 98% of the total for Cd, Cr, Cu, Ni, Pb and Zn, respectively. Under the conditions used, lability of individual metals is related to the anthropogenic component of the samples. Enrichment factors and anthropogenic fraction are estimated for each metal. Some interannual changes are investigated (Pb, Zn). The observed increase of Zn inputs may be linked to local input from the Nice district waste plant (commissioned in 1988), 6.5 km away.

Transfer of atmospheric matter through the euphotic layer in the northwestern Mediterranean: seasonal pattern and driving forces

Abstract The transfer of atmospheric particulate matter through the surface marine layer was studied by comparing atmospheric and marine fluxes. Time series were obtained from the coupling of a coastal atmospheric sampling station (Cap Ferrat, French Riviera) and a marine sampling site (DYFAMED site, central Ligurian Sea). Liquid phase traps were used for measuring total atmospheric fluxes and sediment traps deployed at 200 m depth for measuring marine fluxes. Fluxes of mass, aluminium, and soluble anthropogenic metals (Cd, Pb and Zn) were obtained from both these reservoirs. Physical and biological time series data acquired at the DYFAMED site also were used to describe a three-step seasonal transfer scenario: (i) In summer and autumn, during the period of water stratification, marine fluxes are low and do not account for the transfer of lithogenic material, as revealed by low Al to mass flux ratios and high proportions of organic carbon at 200 m depth. Atmospheric material accumulates along the thermocline, while a series of physico-chemical processes lead to the formation of small (⩽150 μm) non-biogenic organic aggregates. (ii) In winter, the sinking of dense water that occurs in the Ligurian Sea is responsible for a rapid downward transfer of the lithogenic matter accumulated in the surface layer. The fact that soluble trace metals (e.g., cadmium) accumulated in the surface layer are only partially found in sediment traps may indicate that sorption processes play a minor role in the formation of organic aggregates, compared with coagulation processes. (iii) In spring, nutrients brought to surface waters by the winter vertical mixing allow phytoplanktonic blooms, and the transfer of atmospheric matter is then governed by the temporal variations of biological activity. The seasonal variability of the vertical transfer leads to the concept of seasonal variability of elemental residence times in the euphotic layer.

The trace metal chemistry of atmospheric dry deposition samples collected at Cap Ferrat: a coastal site in the Western Mediterranean

A series of 10 dry deposition samples were collected on a surrogate plate over a period of 8 months at Cap Ferrat, a site on the Western Mediterranean coast, and analysed for Al, Fe, Mn, Ni, Co, Cr, Cu, Zn and Pb. Relatively few data sets for trace metal dry deposition are available in the literature, and considerable difficulties are inherent in the use of surrogate plates for the collection of dry deposition. However, the trace metal chemistry of the plate-collected dry deposition at the Cap Ferrat site generally mimics the trends predicted from theoretical metal deposition velocities. The dry deposition is dominated by the fall-out of larger-size particles and during the parent aerosol→dry deposition sequence there is a strong, particle size-mediated, fractionation of the crust-dominated, non-enriched elements (NEEs) from the anthropogenic-dominated, anomalously enriched elements (AEEs), with the latter being depleted in the dry deposition. As a result, although the AEEs in the dry deposition are still enriched relative to average crustal material, the dry deposition and the parent aerosols have different `chemical characters'. Further, the dry deposition has a more homogenous trace metal composition than the parent aerosol. The depletion of the AEEs in the dry deposition, relative to the parent aerosol, has important implications for sea water solubilisation. To assess this, a technique is outlined which allows the solubilities of Cu, Zn and Pb to be estimated on the basis of their EFcrust values in atmospheric particulates. The technique reveals that the solubilities of Cu, Zn and Pb from the dry deposition are less than those which would be predicted from data on the parent aerosol. A comparison between the dry and wet trace metal deposition fluxes at the Cap Ferrat site shows that the particulate fraction dominates the dry deposition of all the metals. However, in wet deposition Cu and Pb switch character and the soluble fraction becomes dominant.

Trend in total atmospheric deposition fluxes of aluminium, iron, and trace metals in the northwestern Mediterranean over the past decade (1985–1997)

The total atmospheric deposition of aluminium (Al), cadmium (Cd), copper (Cu), iron (Fe), manganese (Mn), nickel (Ni), lead (Pb), and zinc (Zn) on the northwestern coast of Corsica (Pirio) was sampled for two years, and their respective concentrations were measured during that period. The sampling station was chosen for its isolation from any local and regional sources of contamination. The year‐to‐year variability of the total atmospheric deposition was found to be high (up to a factor of 2). Using Al as the crustal reference indicates that Pb, Cd, and Zn are mainly associated with man‐made aerosols (&gt;85%), and Fe is mainly associated with crustal aerosols (&gt;70 %). However, our results indicate that Saharan dust is a potential source of “natural” lead, especially in the case of a major input of dust to the northwestern Mediterranean. To determine the spatiotemporal variability of the trace metals over the northwestern Mediterranean Sea, the observed fluxes were compared to those found in the past decade using the same methodology. The comparison indicated a relative homogeneity of Cu and Ni fluxes over the northwestern Mediterranean and over the past decade. The decrease found in Al and Fe since 1985 (by a factor of 4 to 6) can be related to the decrease in Saharan dust fallout. The limitation in the use of lead additives in gasoline may have resulted in a decrease in the European atmospheric lead emissions by a factor of about 6 since 1985 and in a maximum decrease in the total atmospheric flux by a factor of 12 at most if the natural interannual variability of atmospheric deposition in this region is taken into account. So the recorded decrease in the atmospheric lead flux since 1985 (by a factor of ∼30) reveals a slight local contamination at the earlier Corsican station. In the case of Cd and Zn, there was a decrease by a factor of 30 and 23, respectively, between the data obtained at La Tour du Valat (July 1988 to June 1989) and those at Pirio (March 1996 to March 1997); such a decrease cannot be the consequence of either a reduction in emissions in Europe as a whole (the factor being at most 4), or the distance from the emission sources. Hence, we can confirm that Zn and Cd fluxes at La Tour du Valat and Zn fluxes at Cap Ferrat were not representative of a long‐range transport to the Mediterranean but the result of a local/regional contamination. The large decrease observed for metals (Cd, Zn, and Pb) mainly mobilized by human activities, results from a combination of the actual diminution of the concentrations due to a reduction in the emissions and the occurrence of local/regional contamination for some elements at some sampling sites.

Phosphorus in rainwater: Partitioning inputs and impact on the surface coastal ocean

Phosphate concentrations in rainwater were measured at a Ligurian coastal sampling site (Cap Ferrat, France) from February 1997 to February 1998 to study the impact of wet atmospheric phosphorus (P) input on the surface ocean. Soluble and particulate fractions were differentiated to evaluate the atmospheric supply of bioavailable P. Complexed and reactive phases within the dissolved fraction were also separated. Preliminary results showed a high temporal variability in total concentration (0.05–4.3 μmol liter−1). The factors controlling the partitioning between reactive and complexed components are not clear. However, the partitioning between dissolved and particulate fractions is linked to emission sources. Soil‐derived dust from the Sahara was identified as an important source of atmospheric P, mainly insoluble. Conversely, anthropogenic emissions are sources of soluble P (i.e., basically bioavailable). A significant part of these emissions could originate from incinerators and/or biomass burning. The different wet fluxes are calculated to total 165 μmol m−2 yr−1, and the dissolved and particulate inputs are 95 and 70 umol m−2 yr−1, respectively. Taking into account the respective sol ubility of such inputs, anthropogenic emissions appear to be responsible for relatively high amounts of bioavailable P. Even if the atmosphere is globally a minor source of nutrients (compared with riverine inputs and marine vertical mixing), it might be the only source of P in oligotrophic conditions. For example, assuming that P is a limiting factor in the Mediterranean Sea, the rain event of 19 June 1997 (17 μmol m−2 of bioavailable P) potentially induced a new production of 0.02 g C m−2, which is a significant value in such conditions. Converted into biomass and integrated over a 5‐‐thick water layer, such an atmospheric input represents 0.35–0.45 mg chlorophyll a m−2, an appreciable portion of the total biomass during this period. This observation underlines the major role of the atmosphere during oligotrophic periods in the western Mediterranean.