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This research focused on the specific diversity of diatoms carried in ballast sediments of ships reaching Canadian ports on the Pacific, Atlantic and the Great Lakes during 2007 and 2009. The inventory of 180 taxa included Thalassiosira, Chaetoceros spores, Cyclotella, Actinocyclus, Aulacoseira, Melosira and Pseudo-nitzschia as the most species-ric...
Recent empirical and statistical evidence suggest that propagule pressure (i.e., number of individuals introduced per event, and the number and frequency of events) and colonization pressure (i.e., number of species released per event, and the number and frequency of events) are of vital importance to invasion success. To explore possible changes i...
Increasing empirical evidence indicates the number of released individuals (i.e. propagule pressure) and number of released species (i.e. colonization pressure) are key determinants of the number of species that successfully invade new habitats. In view of these relationships, and the possibility that ships transport whole communities of organisms,...
Marine pelagos is the largest habitat on our planet; it covers ∼70% of the earth’s surface area, and the average 200-m-illuminated
upper layer encompasses an enormous body of water that extends from the Arctic through the tropics to the Antarctic Ocean.
The microscopic inhabitants of this vast environment are comprised by organisms adapted to life...
marine microalgae, diatoms, dinoflagellates, cyanobacteria, algal blooms
Introduction Diatoms are major contributors to total primary production as well as many important biogeochemical processes in aquatic environments (Falkowski et al., 1998; Smetacek, 1999). Nonetheless, a small number of species (<30) have been recognized as harmful to fisheries, wildlife, or people, through production of either a toxin or various e...
The Brazilian coast extends for about 8000 km from Cape Orange (4°N) to Chui (34°S) (Fig. 27.1). This long coastline comprises a variety of ecosystems under the influence of oligotrophic waters transported by two western boundary currents, the Brazil and North Brazil currents (Stramma and England 1999), together with continental influences related...
The objective of this study is to compile the inventory of nearly 100 years of research about the phytoplankton species cited for the coast of the state of São Paulo, Brazil. A state-of-the-art study on the local biodiversity has long been needed to provide a baseline for future comparisons. This type of data is scattered in old scientific journals...
The region of the nuclear ribosomal DNA (rDNA) operon containing the small subunit (SSU), internal transcribed spacer 1 (ITS1), and a portion of the 5.8s rDNA gene was sequenced in one isolate each of Pseudo-nitzschia multiseries (Hasle) Hasle and Pseudo-nitzschia pungens (Grunow in Cleve & Möller) Hasle. The SSUs of these two species were highly s...
The objective of this research was to assess the species composition and relative abundance of the surf-zone phytoplankton of 20 beaches in the State of Sao Paulo (23 degrees 20'-25 degrees S), Brazil, from August 2004 to July 2006. Once a month, surface hauls with a 20 mu m-mesh phytoplankton net were taken "simultaneously" (within an 8-hour perio...
Variations of nanoplankton (2-20 µm) and filamentous bacteria (diameter: 0.5-2.0 µm) of Guanabara Bay (RJ, Brazil) are presented, considering cell density and carbon content of auto- and heterotrophs. Our goal is to contribute to future modeling of local trophic dynamics. Subsurface water samples were taken weekly during the year 2000 at two sites:...
Much time and resources have been invested in understanding plankton dynamics in Guanabara Bay (Brazil), but no attention has been devoted to the protozooplankton. To fulfill this lacuna, abundance and composition of protozooplankton were investigated from January to December - 2000 in fortnightly surface water samplings at two distinct water quali...
The occurrence of Pseudo-nitzschia brasiliana Lundholm, Hasle & Fryxell, a recently described marine diatom, is reported for two distinct environments on the coast of the state of Rio de Janeiro, Brazil, during the El Niño-ENSO summer of 1998. These occurrences took place almost simultaneously, as a bloom event, which is defined here not only throu...
During a European Union Concerted Action study on species introductions, an intercalibration workshop on ship ballast water
sampling techniques considered various phytoplankton and zooplankton sampling methods. For the first time, all the techniques
presently in use worldwide were compared using a plankton tower as a model ballast tank spiked with...
PETROBRAS developed a new method for ballast water exchange in tankers, which deals with the coming IMO regulations on ballast water. PETROBRAS' method, which has been called Brazilian Dilution Method (BDM) or Dilution Method, involves a ballast loading through the top with simultaneous unloading from the bottom of the tanks. A simulation study was...
A baia de Guanabara e um dos ecossistemas tropicais mais eutrofizados do mundo. Sua hidrobiologia varia segundo um tutor temporal definido pelo verao chuvoso e um duplo gradiente espacial, vertical e horizontal condicionado pela influencia da mare e dos e efluentes continentais. O impacto antropico manifesta-se nas areas internas por elevados teore...
Pseudo-nitzschia pungens var. cingulata var. nov. (Bacillariophyceae) is described based on light and scanning electron microscopy of field and cultured material from Monterey Bay, California. Cultures of P. pungens (Grunow in Cleve & Mailer) Hasle from widely separated coastal regions were studied for comparison. Pseudo-nitzschia pungens var, cing...
The known history of the genus Pseudo-nitzschia [mostly reported in error as Nitzschia seriata (PT Cleve) H. Peragallol on the West Coast of the USA is traced in three time periods: the early observations of 1920-1943, later publications in 1960-1990, and recent publications after known domoic acid events in 1991-1996. The genus has been widespread...
Cultured isolates of Pseudonitzschia australis Frenguelli, P. delicatissima (Cleve) Heiden, P. americana (Hasle) Fryxell, P. pungens (Grunow) Hasle, and P. pungens f. multiseries (Hasle) Hasle from Monterey Bay, California, were compared on the basis of their large-subunit ribosomal RNA gene (LsrDNA). Pseudonitzschia australis, P. pungens f. multis...
Cultured isolates of Pseudonitzschia australis Frenguelli, P. delicatissima (Cleve) Heiden, P. americana (Hasle) Fryxell, P. pungens (Grunow) Hasle, and P. pungens f. multiseries (Hasle) Hasle from Monterey Bay, California, were compared on the basis of their large-subunit ribosomal RNA gene (LsrDNA). Pseudonitzschia australis, P. pungens f. multis...
In the past five years, awareness of domoic acid has increased from localized problems in Canada to outbreaks along both North American coasts. The phycotoxin domoic acid causes Amnesic Shellfish Poisoning (ASP) in humans and can be fatal. The known species of phytoplankton responsible for production of domoic acid include some pennate diatom speci...
In the past five years, awareness of domoic acid has increased from localized problems in Canada to outbreaks along both North American coasts. The phycotoxin domoic acid causes Amnesic Shellfish Poisoning (ASP) in humans and can be fatal. The known species of phytoplankton responsible for production of domoic acid include some pennate diatom speci...
Pseudonitzschia australis Frenguelli has been identified as the domoic acid producer responsible for pelican mortalities and shellfish and other seafood quarantines on the west coast of the United States. During autumn 1991, Monterey Bay was the focus of the highest reported concentration of domoic acid in shellfish and anchovies. P. australis has...
Guanabara Bay forms an ecological unity with serious environmental problems derived from an accelerated and unorganized process of urbanization without the necessary support. The UFRJ/Institute of Biology soon became aware of these problems and since 1985 it has been developing systematic studies about the bay. Based on data obtained from previous...