Volume 52, Issue 4

The carragenophyte Kappaphycus alvarezii has been introduced into tropical regions, including Brazil, for aquaculture purposes. Our study estimated the biomass loss of farmed cuttings, the establishment of cuttings outside the rafts, the occurrence of spores, and evaluated the invasive potential of K. alvarezii at three sites in Rio de Janeiro state. Temperature, salinity, water transparency, wind velocity and direction (hydrodynamic indicator) and solar radiation (irradiance availability indicator) varied spatially. We found no spores in cultivated cuttings and no verified spore recruitment on artificial substrata. Biomass loss of cuttings varied temporally; however, it was restricted to the cultivation management area of one site and was low compared to native algal biomass. The establishment of cuttings was apparently limited by herbivory at Ilha Grande Bay and controlled by water transparency, hydrodynamics and temperature at Sepetiba Bay. The invasive potential of K. alvarezii was considered remote. However, the use of environmental protocols for cultivation activities is necessary to prevent environmental impacts, mainly in tropical regions.

Phytoplankton abundance and seasonality in the northeastern Adriatic Sea were directly related to the annual regime of the Po River discharge in the period 2002–2007. In 2005, 2006, and 2007, there was a shift in the timing of the annual Po River maximum discharge and of phytoplankton maxima from spring to autumn. In addition, the eastern coastal area was greatly influenced by oligotrophic karstic rivers and the Eastern Adriatic Current. Dominant phytoplankton taxa were defined on the basis of abundance and frequency of appearance. Such an approach may help in the comparison of phytoplankton communities within different environments. The dominant taxa were the diatoms Cerataulina pelagica , Chaetoceros socialis , Chaetoceros vixvisibilis and Pseudo-nitzschia spp., which appeared at maximum abundances >10 6 cells l -1 in more than 20% of samples. Among other phytoplankton, the most common was the coccolithophorid Emiliania huxleyi (maximum abundance of 2×10 5 cells l -1 in 50% of samples), and the dinoflagellate Prorocentrum minimum (maximum abundance of 3×10 5 cells l -1 in 12% of samples). The present state of the phytoplankton community may provide valuable information for evaluation of possible future environmental changes in the shallow Mediterranean ecosystem.

The Yellow Sea, located between the Korean Peninsula and mainland China, was completely exposed during the last glacial maximum of the Pleistocene when the sea level was 120–130 m below the present level. We studied patterns of genetic variation in a marine red alga to examine whether the recent recolonization of algal populations occurred on the west coast of Korea after the end of the last glacial maximum. In total, 53 specimens of the red alga Ceramium japonicum were collected in Korea and Japan. We examined the geographic distribution of haplotypes and patterns of migration using mitochondrial cox 1 and plastid rbc L. From the specimens collected, 22 cox 1 haplotypes and eight rbc L haplotypes were identified. The network and neutrality tests for cox 1 support three clusters (which are geographically grouped into east, south, and west coast populations) and provide evidence for population expansion on the west coast. The levels of gene flow were high in the south coast→west coast direction. Analysis of molecular variation in two protein-coding genes revealed significant genetic structure among the three coasts. The results support the concept that C. japonicum populations recolonized the west coast from the south coast following sea level rise in the northern hemisphere after the last glacial maximum during the late Pleistocene.

We present new data on marine algae of the South Kamchatka state wildlife sanctuary (Yuzhno-Kamchatskii Zakaznik, Russia), a protected natural area of federal significance. The species list of macrophytic marine algae is accompanied by information on their reproduction and distribution. This list updates the taxonomy and expands a previous list, with many new species, including 2 species previously unknown from the Pacific coasts of Russia ( Colaconema endophyticum , Acrochaetium plumosum ), 2 species new to the coasts of Kamchatka ( Colaconema daviesii and Acrochaete geniculata ), and 11 species recorded for the first time from the area studied ( Erythrocladia irregularis , Palmaria hecatensis , Palmaria mollis , Meiodiscus concrescens , Crossocarpus lamuticus , Cirrulicarpus ruprechtianum , Rhodomela sibirica , Urospora elongata , Zygomitus reticulatus , Acrochaete ramosa , Acrochaete pterosiphoniae ) (Nagai) Zhigadlova, comb. nov. (= Entocladia pterosiphoniae ). The importance of the wildlife sanctuary for the conservation of biodiversity in Kamchatka is noted.

Gracilaria “ verrucosa ” is now regarded an invalid name, with G. gracilis being used in recent studies of the genus from the Russian coast of the East Sea (Sea of Japan). This has created nomenclatural confusion for members of the genus in this region. Here we revise the taxonomy of G. “ verrucosa ” from Peter the Great Bay (East Sea, Russia) based on morpho-anatomical characters and comparisons of nuclear small subunit rDNA, plastid rbc L and mitochondrial cox 1 sequence data. No differences were found between sequences for attached and unattached forms of G. “ verrucosa ”. Molecular data also indicate that G. “ verrucosa ” from Peter the Great Bay is conspecific with Gracilaria vermiculophylla from the northwestern Pacific, and the Russian population is closely related to Korean-Japanese populations from the East Sea rather than with populations on the Pacific coast of Japan.

We studied effects of salt stress on proline accumulation and the activities of proline metabolic enzymes in reed, a salt-tolerant, cosmopolitan, aquatic grass. A concentration-dependent inhibition of plant growth occurred in the presence of NaCl, which was accompanied by high amounts of proline accumulation. Reed tolerance of salt stress reaches a limit at approximately 200 m m NaCl. Free proline content and pyrroline-5-carboxylate synthetase (P5CS) activity both increased with salt stress treatment, while ornithine aminotransferase (OAT) activity appeared to be unaffected, suggesting that the glutamate pathway, rather than the ornithine pathway, plays a vital role in proline accumulation during osmotic regulation. The activity of the proline degrading enzyme, proline dehydrogenase (PDH), decreased under salt stress, indicating that proline catabolism may also be responsible for proline accumulation in response to salt stress. Furthermore, high salinity ≥250 m m NaCl, which stops growth of reed, decreases proline accumulation and P5CS, OAT, and PDH activities. This suggests that changes in enzyme activities of proline metabolism coupled with increased proline accumulation are involved in osmotic regulation of reed plants only when they are grown at salinities ≤200 m m NaCl.

The aquatic hyphomycete genus Sigmoidea , with freshwater and marine representatives, is re-examined at the morphological and molecular levels. Currently six species are accepted, four from freshwater habitats ( S. prolifera , S. aurantiaca , S. contorta , S. praelonga ) and two marine species ( S. marina , S. luteola ). Phylogenetic analyses of the ribosomal small subunit rRNA gene sequences of freshwater and marine Sigmoidea species indicate that the marine species are distantly placed from the freshwater species, S. prolifera and Pseudosigmoidea cranei . The latter species are placed in the Dothideomycetes, in sister clades, with 81% bootstrap support. The phylogenetic placement of both marine Sigmoidea species, inferred from large subunit rRNA gene sequences, was within the genus Corollospora (Halosphaeriales, Sordariomycetes, Pezizomycotina). An undescribed Sigmoidea species isolated from the Baltic Sea and one previously incorrectly identified as S. marina from Japan ( S. parvula sp. nov.) formed a clade together with Corollospora quinqueseptata and Varicosporina ramulosa , and were located in a sister group to S. luteola and S. marina . Based on morphological and phylogenetic evidence, Halosigmoidea gen. nov. is proposed to accommodate the three marine Sigmoidea species ( S. luteola , S. marina , S. parvula sp. nov.). Identification keys to the genera Halosigmoidea , Pseudosigmoidea and Sigmoidea , and Halosigmoidea species are provided.

The first recorded macroalgal bloom to occur at Kure and Midway Atolls in the highly protected Northwestern Hawaiian Islands was observed during summer 2008 on shallow water reefs. The native green macroalga Boodlea composita formed dense mats centimeters in thickness in select areas and formed decomposing masses on beaches at Kure Atoll. Mild oceanographic conditions during winter 2008 likely weakened lagoonal flushing systems, and when coupled with weeks of low wind and warm sea surface temperatures during the proceeding summer months, physical conditions within the lagoons of each atoll fostered rapid growth of this normally non-blooming alga.

No abstract available

No abstract available