Search

Your search keyword '"Scardi, M."' showing total 161 results
Start Over Author "Scardi, M."
161 results on '"Scardi, M."'

2. A Machine Learning Approach to Chlorophyll a Time Series Analysis in the Mediterranean Sea

Author

Mattei, F., Scardi, M., Goos, Gerhard, Founding Editor, Hartmanis, Juris, Founding Editor, Bertino, Elisa, Editorial Board Member, Gao, Wen, Editorial Board Member, Steffen, Bernhard, Editorial Board Member, Woeginger, Gerhard, Editorial Board Member, Yung, Moti, Editorial Board Member, Del Bimbo, Alberto, editor, Cucchiara, Rita, editor, Sclaroff, Stan, editor, Farinella, Giovanni Maria, editor, Mei, Tao, editor, Bertini, Marco, editor, Escalante, Hugo Jair, editor, and Vezzani, Roberto, editor

Published
2021
Full Text
View/download PDF

4. Assessing the uncertainties of model estimates of primary productivity in the tropical Pacific Ocean

Author

Friedrichs, MAM, Carr, ME, Barber, RT, Scardi, M, Antoine, D, Armstrong, RA, Asanuma, I, Behrenfeld, MJ, Buitenhuis, ET, Chai, F, Christian, JR, Ciotti, AM, Doney, SC, Dowell, M, Dunne, J, Gentili, B, Gregg, W, Hoepffner, N, Ishizaka, J, Kameda, T, Lima, I, Marra, J, Mélin, F, Moore, JK, Morel, A, O'Malley, RT, O'Reilly, J, Saba, VS, Schmeltz, M, Smyth, TJ, Tjiputra, J, Waters, K, Westberry, TK, and Winguth, A

Subjects
Primary production, Modeling, Remote sensing, Satellite ocean color, Statistical analysis, Tropical Pacific Ocean (15 degrees N to 15 degrees S and 125 degrees E, to 95 degrees W), Oceanography
Abstract

Depth-integrated primary productivity (PP) estimates obtained from satellite ocean color-based models (SatPPMs) and those generated from biogeochemical ocean general circulation models (BOGCMs) represent a key resource for biogeochemical and ecological studies at global as well as regional scales. Calibration and validation of these PP models are not straightforward, however, and comparative studies show large differences between model estimates. The goal of this paper is to compare PP estimates obtained from 30 different models (21 SatPPMs and 9 BOGCMs) to a tropical Pacific PP database consisting of ∼ 1000 14C measurements spanning more than a decade (1983-1996). Primary findings include: skill varied significantly between models, but performance was not a function of model complexity or type (i.e. SatPPM vs. BOGCM); nearly all models underestimated the observed variance of PP, specifically yielding too few low PP (< 0.2 g C m- 2 d- 1) values; more than half of the total root-mean-squared model-data differences associated with the satellite-based PP models might be accounted for by uncertainties in the input variables and/or the PP data; and the tropical Pacific database captures a broad scale shift from low biomass-normalized productivity in the 1980s to higher biomass-normalized productivity in the 1990s, which was not successfully captured by any of the models. This latter result suggests that interdecadal and global changes will be a significant challenge for both SatPPMs and BOGCMs. Finally, average root-mean-squared differences between in situ PP data on the equator at 140°W and PP estimates from the satellite-based productivity models were 58% lower than analogous values computed in a previous PP model comparison 6 years ago. The success of these types of comparison exercises is illustrated by the continual modification and improvement of the participating models and the resulting increase in model skill. © 2008 Elsevier B.V.

Published
2009

27. An assessment of phytoplankton primary productivity in the Arctic Ocean from satellite ocean color/in situ chlorophyll‐a‐based models

Author

Lee, Y., Matrai, P., Friedrichs, M., Saba, V., Antoine, D., Ardyna, M., Asanuma, I., Babin, M., Belanger, S., Benoit-Gagne, M., Devred, E., Fernandez-Mendez, M., Gentili, B., Hirawake, T., Kang, S., Kameda, T., Katlein, C., Lee, S., Lee, Z., Melin, F., Scardi, M., Smyth, T., Tang, S., Turpie, K., Waters, K., and Westberry, T.

Abstract

We investigated 32 net primary productivity (NPP) models by assessing skills to reproduce integrated NPP in the Arctic Ocean. The models were provided with two sources each of surface chlorophyll-a concentration (chlorophyll), photosynthetically available radiation (PAR), sea surface temperature (SST), and mixed-layer depth (MLD). The models were most sensitive to uncertainties in surface chlorophyll, generally performing better with in situ chlorophyll than with satellite-derived values. They were much less sensitive to uncertainties in PAR, SST, and MLD, possibly due to relatively narrow ranges of input data and/or relatively little difference between input data sources. Regardless of type or complexity, most of the models were not able to fully reproduce the variability of in situ NPP, whereas some of them exhibited almost no bias (i.e., reproduced the mean of in situ NPP). The models performed relatively well in low-productivity seasons as well as in sea ice-covered/deep-water regions. Depth-resolved models correlated more with in situ NPP than other model types, but had a greater tendency to overestimate mean NPP whereas absorption-based models exhibited the lowest bias associated with weaker correlation. The models performed better when a subsurface chlorophyll-a maximum (SCM) was absent. As a group, the models overestimated mean NPP, however this was partly offset by some models underestimating NPP when a SCM was present. Our study suggests that NPP models need to be carefully tuned for the Arctic Ocean because most of the models performing relatively well were those that used Arctic-relevant parameters.

Published
2015

28. Evaluating the ecological status of streams and rivers by means of fish assemblages according to 2000/60/CE Directive: a method based on the reconstruction of expert judgment using artificial techniques

Author

SCARDI M, CATAUDELLA S, CICCIOTTI E, CIUFFA D, COLOMBARI P. T, DI DATO P, GIBERTINI G, LARSEN S, MANCINI L, MOCCIA G, MUNAFÒ M, GRYGIELEWICZ M, PACE G, RUSSO T, TANCIONI L., SCALICI, MASSIMILIANO, Scardi, M, Cataudella, S, Cicciotti, E, Ciuffa, D, COLOMBARI P., T, DI DATO, P, Gibertini, G, Larsen, S, Mancini, L, Moccia, G, Munafò, M, Grygielewicz, M, Pace, G, Russo, T, Scalici, Massimiliano, and Tancioni, L.

Published
2006

29. The sxt Gene and Paralytic Shellfish Poisoning Toxins as Markers for the Monitoring of Toxic Alexandrium Species Blooms

Author

Penna, Antonella, Perini, Federico, Dell’Aversano, Carmela, Capellacci, Samuela, Tartaglione, Luciana, Giacobbe, Maria Grazia, Casabianca, Silvia, Fraga, Santiago, Ciminiello, P (Patrizia), Scardi, (M) Michele, Penna, Antonella, Perini, Federico, Dell’Aversano, Carmela, Capellacci, Samuela, Tartaglione, Luciana, Giacobbe, Maria Grazia, Casabianca, Silvia, Fraga, Santiago, Ciminiello, P (Patrizia), and Scardi, (M) Michele

Abstract

Paralytic shellfish poisoning (PSP) is a serious human illness caused by the ingestion of seafood contaminated with saxitoxin and its derivatives (STXs). These toxins are produced by some species of marine dinoflagellates within the genus Alexandrium. In the Mediterranean Sea, toxic Alexandrium spp. blooms, especially of A. minutum, are frequent and intense with negative impact to coastal ecosystem, aquaculture practices and other economic activities. We conducted a large scale study on the sxt gene and toxin distribution and content in toxic dinoflagellate A. minutum of the Mediterranean Sea using both quantitative PCR (qPCR) and HILIC-HRMS techniques. We developed a new qPCR assay for the estimation of the sxtA1 gene copy number in seawater samples during a bloom event in Syracuse Bay (Mediterranean Sea) with an analytical sensitivity of 2.0 × 10° sxtA1 gene copy number per reaction. The linear correlation between sxtA1 gene copy number and microalgal abundance and between the sxtA1 gene and STX content allowed us to rapidly determine the STX-producing cell concentrations of two Alexandrium species in environmental samples. In these samples, the amount of sxtA1 gene was in the range of 1.38 × 105 − 2.55 × 108 copies/L and the STX concentrations ranged from 41−201 nmol/L. This study described a potential PSP scenario in the Mediterranean Sea.

Published
2015

32. Genetic diversity of the genus Ostreopsis Schmidt:phylogeographical considerations and molecularmethodology applications for field detectionin the Mediterranean Sea

Author

Penna, Antonella, Fraga, S., Battocchi, Cecilia, Casabianca, Silvia, Perini, Federico, Capellacci, Samuela, Casabianca, Anna, Riobó, P., Giacobbe, M. G., Totti, C., Accoroni, S., Vila, M., Reñé, A., Scardi, M., Aligizaki, K., NGUYEN NGOC, L., and Vernesi, C.

Subjects
ribosomal genes, distribution, Mediterranean Sea, benthic dinoflagellate, benthic dinoflagellate, distribution, Mediterranean Sea, Ostreopsis, ribosomal genes, qrt-PCR, Ostreopsis, qrt-PCR
Published
2012

37. Coralligenous and maërl habitats: predictive modelling to identify their spatial distributions across the Mediterranean Sea

Author

Martin, C. S., Giannoulaki, M., De Leo, F., Scardi, M., Salomidi, M., Knitweiss, L., Pace, M. L., Garofalo, G., Gristina, M., Ballesteros, E., Bavestrello, G., Belluscio, A., Cebrian, E., Gerakaris, V., Pergent, G., Pergent-martini, C., Schembri, P. J., Terribile, K., Rizzo, L., Ben Souissi, J., Bonacorsi, M., Guarnieri, G., Krzelj, M., Macic, V., Punzo, E., Valavanis, V., Fraschetti, S., Martin, C. S., Giannoulaki, M., De Leo, F., Scardi, M., Salomidi, M., Knitweiss, L., Pace, M. L., Garofalo, G., Gristina, M., Ballesteros, E., Bavestrello, G., Belluscio, A., Cebrian, E., Gerakaris, V., Pergent, G., Pergent-martini, C., Schembri, P. J., Terribile, K., Rizzo, L., Ben Souissi, J., Bonacorsi, M., Guarnieri, G., Krzelj, M., Macic, V., Punzo, E., Valavanis, V., and Fraschetti, S.

Abstract

Bioconstructions such as coralligenous outcrops and maerl beds are typical Mediterranean underwater seascapes. Fine-scale knowledge on the distribution of these sensitive habitats is crucial for their effective management and conservation. In the present study, a thorough review of existing spatial datasets showing the distribution of coralligenous and maerl habitats across the Mediterranean Sea was undertaken, highlighting current gaps in knowledge. Predictive modelling was then carried out, based on environmental predictors, to produce the first continuous maps of these two habitats across the entire basin. These predicted occurrence maps for coralligenous outcrops and maerl beds provide critical information about where the two habitats are most likely to occur. The collated occurrence data and derived distribution model outputs can help addressing the challenge of developing basin-wide spatial plans and to guide cost-effective future surveys and monitoring efforts towards areas that are presently poorly-sampled.

Published
2014
Full Text
View/download PDF

38. Indice di funzionalità perilacuale

Author

Bernabei, S., Cappelletti, C., Ciutti, F., Dallafior, V., Dalmiglio, A., Fabiani, C., Mancini, L., Monauni, C., Pozzi, S., Scardi, M., Tancioni, L., and Siligardi, C.M.

Published
2009

41. Indice di funzionalità perilacuale (IFP)

Author

Siligardi, M., Bernabei, S., Cappelletti, C., Ciutti, F., Dallafior, V., Dalmiglio, A., Fabiani, C., Mancini, L., Monauni, C., Pozzi, S., Scardi, M., and Tancioni, L.

Published
2009

42. SYMPLEX Experiment: fist results on oceanic mesoscale dynamics and related primary production from AVHRR and SeaWiFS satellite data and field experiments

Author

Bohm E., Buongiorno Nardelli B., Brunet C., Casotti R., Conversano F., Corato F., D’Acunzo E., D’Ortenzio F., Iudicone D., Lazzara L., Marcelli M., Marullo S., Massi L., Mori G., Nardello I., Nuccio C., Ribera d’Alcalà M., Saggiomo V., Santoleri R., Scardi M., Sparnocchia S., Tozzi S., Zoffoli S., MANGONI, OLGA, Bohm, E., Buongiorno Nardelli, B., Brunet, C., Casotti, R., Conversano, F., Corato, F., D’Acunzo, E., D’Ortenzio, F., Iudicone, D., Lazzara, L., Mangoni, Olga, Marcelli, M., Marullo, S., Massi, L., Mori, G., Nardello, I., Nuccio, C., Ribera d’Alcalà, M., Saggiomo, V., Santoleri, R., Scardi, M., Sparnocchia, S., Tozzi, S., and Zoffoli, S.

Published
1998

46. Valutazione dello stato ecologico dei sistemi lotici mediante analisi dei popolamenti ittici ai sensi della direttiva 2000/60CE: una proposta basata sulla ricostruzione del giudizio esperto con tecniche di intelligenza artificiale

Author

Scardi, M, Cataudella, S, Ciccotti, E, Ciuffa, D, Colombari, P, Di Dato, P, Gibertini, G, Larsen, S, Mancini, L, Moccia, G, Munafò, M, Grygielewicz, M, Pace, G, Russo, T, Scalici, M, and Tancioni, L

Subjects
Water Framework Directive, fish assemblages, neural networks, expert system, Settore BIO/07, neural networks, expert system
Published
2006

Catalog

Books, media, physical & digital resources
See catalog results