12th International Conference on Harmful Algae

INTERNATIONAL SOCIETY FOR THE STUDY OF HARMFUL ALGAE12 th <strong>International</strong> <strong>Conference</strong> on Harmful Algae, Copenhagen, Denmark, 4-8 September 2006isolated from Alfacs Bay arepresented in this study. The identityof the species was confirmed byanalysis of the ITS1, 5.8S and ITS2of the nuclear-encoded rRNAsequences. Intraspecific andinterspecific variability of thecultures was also assessed byanalysis of the nuclear-encodedrRNA in order to develop speciesspecificoligonucleotide probestargeting the rRNA for theidentification of Pseudo-nitzschiaspp. by fluorescent in situhybridisation (FISH) techniques.PO.06-06Seasonal dynamics of aPlanktothrix rubescensdominatedphytoplanktoncommunity and toxic compoundsin Lake Albano (Rome, Italy)Session: PO.06 - Population dynamicsNTW Ellwood 1 , P Albertano 2 , EViaggiu 2 , R Mosello 3 , R Funiciello 11 Università Roma Tre, ROME, Italy2 Università di Tor Vergata, Roma, ROME,Italy3 CNR-ISE, VERBANIA-PALLANZA, ItalyLake Albano is situated in the ColliAlbani Volcano 25 km southeast ofthe city of Rome. Physico-chemicalmeasurements and analyses ofwater were made at discrete depthintervals across the full depth profileof the lake (0-160m). Analyses ofphytoplankton toxins were made onnet samples using MALDI-TOFmass spectrometry andobservations and counts made onsamples from discrete depthsbetween 0-30m using a 1-L Niskinbottle. Sampling was made on fiveoccasions between 2005 and 2006to incorporate complete seasonalvariation. The lake is classifiedmeso-eutrophic; based on averageepilimnion total phosphorus (5-92µg/L), total nitrogen (365-809 µg/L)and chlorophyll a (3-14 µg/L). Thephytoplankton community wasvariably dominated by thecyanobacterium Planktothrix(Oscillatoria) rubescens with adistribution across a small depthrange under thermal stratification.With an increase in mixing depth inMay-05 down to 100m and Jan/Mar-06 full overturn, P. rubescens wasdistributed throughout the epilimnionand caused surface blooms.Throughout the study period therewere three variants of microcystinidentified, the major variant, presentin every sample, was [D-Asp]-MCYST-RR. The variants, (Asp)-MCYST-LR and MCYST-YR whereabsent in autumn. This is the firststudy to show the diversity ofmicrocystins produced by P.rubescens in Lake Albano.PO.13-18Distribution of toxic Dinophysisspecies and contamination ofshellfish along the Doukkalacoast (Moroccan Atlantic water)Session: PO.13 - Regional eventsBtissam Ennaffah 1 , Abdelghan Chafik 21 Institut National de Recherche Halieutiq,OUALIDIA-PAR EL JADIDA, Morocco2 Institut National de Rechrche Halieutiqu,CASA, MoroccoThe distribution of Dinophysisspecies and the contamination ofshellfish in the Doukkala coast(Moroccan Atlantic water) werestudied.During the monitoring program,samples were taken bimonthly from2004 to 2005 at about elevensampling stations, situated on 2lagoons and open sea sites alongthe coast.The presence of toxic species ofDinophysis varied seasonally, withmaximum abundance registered in168