• ALGAE
• /
• v.22 no.1
• /
• pp.17-21
• /
• 2007

Sargassum filicinum Harvey, a brown alga (Phaeophyceae) native to Northeastern Asia, has been recently reported from the coast of Southern California (USA). Here we report the occurrence and range extension of this introduced species, as we found the alga at La Jolla and Rancho Packard in Todos Santos Bay, Baja California, Mexico. The first collections of S. filicinum correspond to several immature plants, found on September 8, 2005, drifting in the intertidal zone at La Jolla. Later on November 9, 2006, we found a well-established population in Rancho Packard in the middle intertidal zone to 2 m depth. Since S. filicinum is an annual monoecious species with air bladders, the risk there is a high risk of spreading rapidly along the Pacific, as in the case for S. muticum. The population in Rancho Packard extends 500 m along the coast, consisting mainly of young plants with an average length of 30 cm and a density of 5 thallus/m2. This is the first record of this invasive species for the Mexican Pacific coast, and it represents the southern limit along the Pacific coast of North America. This finding suggests that this invasive species has successfully colonized the Pacific coast of North America and its distributional range is still expanding.

• ALGAE
• /
• v.17 no.3
• /
• pp.171-185
• /
• 2002

The standing crop of genus Microcystis, microcystin concentrations and environmental factors were monitored at stations of the lower reaches of the Nakdong River in 1998 and 1999 during the periods of its occurrence. The Microcystis were observed from May to Octorber, and the cell density was highest at Station Seonam up to 250,000 cells${\cdot}ml^{-1}$ forming scum over the water surface. There were signigicant relationships between the standing crop of Microcystis and nitrate nitrogen, total phosphorus concentrations and Ph. Presumably these parameters were important in the succession to Microcystis dominated phytoplankton community in the summer period in the river. However, Ammonium nitrogen, phosphate phosphorus concentrations and N/P ratio were not critical factors. The Microcystis bloom was notable above $25^{\circ}C$ of surface water temperature. Microcystins were detected from May to November in the algal materials from the river. The 84.2% of algal materials with Microcystis exhibited the microcystin with the maximum of 1711.8 ${\mu}g{\cdot}g^{-1}$ dw. The microcystin concentrations in the algal materials were significantly related to the stading crop of Microcystis, which was the primary determinant factor in the toxin levle of algal materials. The concentrations were also significantly related to pH of the water column in the positive pattern.

• ALGAE
• /
• v.22 no.3
• /
• pp.201-207
• /
• 2007

For getting primary cue of restoration, the algal flora and intertidal community structure of Deokjeokdo, Yeonpyeongdo and Ganghwado were investigated for from February to November 2006. The total of 28 species, including five Chlorophytes, five Phaeophytes, 17 Rhodophytes and one sea grass were identified. The occurrence of species according to sampling site was 22 species in Deokjeokdo, seven species in Yeonpyeongdo and four species in Ganghwado. Among them Gloiopeltis furcata, Ulva pertusa and Sargassum horneri in Deokjeokdo, Scytosiphon lomentaria in Yeonpyeongdo, Enteromorpha prolifera in Ganghwado were ominants. The algal zonation of intertidal zone was figured out by Gloiopeltis furcata, Caulacanthus okamurae – Corallina pilulifera – Ulva pertusa, Ahnfeltiopsis flabelliformis, Sargassum horneri, Undaria pinnatifida in Deokjeokdo, Bangia atropurpurea – Scytosiphon lomentaria – Ahnfeltiopsis flablleiformis in Yeonpyeongdo from upper to lower zone and Enteromorpha prolifera, Enteromorpha linza – Sargassum thunbergii, Myelophycus simplex in Ganghwado from middle to lower zone. The average of biomass was measured as 80.6 g dry wt. m–2 in Deokjeokdo, 32.2 g dry wt. m–2 in Yeonpyeongdo and less than 1 g dry wt. m–2 in Ganghwado.

• ALGAE
• /
• v.22 no.2
• /
• pp.117-123
• /
• 2007

The seasonal change of algal flora and intertidal community structures of Bagryoungdo Island was investigated at Dumujin from February to November 2006. The description of subtidal algal community was made in October by Scientific SCUBA-diving. The total of 43 species, including 6 Chlorophytes, 6 Phaeophytes, 29 Rhodophytes and 2 sea grasses were identified in this survey. The occurrence of species according to season, listed as follows, 26 species in winter, 34 in spring, 18 in summer and 18 in autumn. Three species, Laminaria japonica, Neorhodomela aculeata and Ulva pertusa were dominant. The algal zonation of intertidal zone was figured out by Porphyra spp., Gloiopeltis furcata, Caulacanthus okamurae, Gelidium divaricatum - Neorhodomela aculeata, Enteromorpha compressa - Ulva pertusa, Dumontia simplex, Laminaria japonica from upper to lower zone. The zonation of subtidal zone was figured out by Ulva pertusa - Laminaria japonica - Zostera marina (sea grass), crustacean red algal population in autumn. The average of biomass of macroalgae was measured as 119.4 g∙dry wt/m2.

• Journal of The Korean Society of Agricultural Engineers
• /
• v.52 no.6
• /
• pp.19-26
• /
• 2010

Batch experiments were conducted to investigate growth and nutrient removal performance of microalgae Chlorella vulgaris by using piggery wastewater in different concentration of pollutants and the common growth models (logistic, Gompertz and Richards) were applied to compare microalgal growth parameters. Removal of nitrogen (N) and phosphorus (P) by Chlorella vulgaris showed correlation with biomass increase, implying nutrient uptake coupled with microalgae growth. The higher the levels of suspended solids (SS), COD and ammonia nitrogen were in the wastewater, the worse growth of Chlorella vulgaris was observed, showing the occurrence of growth inhibition in higher concentration of those pollutants. The growth parameters were estimated by non-linear regression of three growth curves for comparative analyses. Determination of growth parameters were more accurate with population as a variable than the logarithm of population in terms of R square. Richards model represented better fit comparing with logistic and Gompertz model. However, Richards model showed some complexity and sensitivity in calculation. In the cases tested, both logistic and Gompertz equation were proper to describe the growth of microalgae on piggery wastewater as well as easy to application.

• ALGAE
• /
• v.21 no.2
• /
• pp.245-251
• /
• 2006

Diurnal and age-related changes in air pressure were measured in air bladders of Ascophyllum nodosum from the Atlantic coast of Nova Scotia. Exterior and interior bladder volumes vary significantly with 4 and 6 y bladders being about 40% larger than 2 y bladders (p < 0.01). Freshly collected bladders yielded a mean pressure of 40.8 ± 6.5 cm H2O. Overnight (20 h) dark treatment at 15°C generated pressure reductions by 80% in 2 y bladders but only by about 30% in 4 and 6 y bladders. Furthermore, in 2 y bladders 8 out of 11 bladders were reduced to atmospheric pressure. Pressure losses were inversely related to pressure recovery after 2.5 h in natural daylight, but after 5 h in daylight there was no significant difference in pressure within the age groups. Even under 25% of full illumination, bladders inflated to full pressure after 5 h. The results show that differences in bladder age and bladder wall thickness have roles in diurnal patterns of bladder inflation and deflation. These results confirm that bladder inflation is based on photosynthetic O2 production and not on partial pressures of O2 in the surrounding medium as was suggested for Sargassum. Chemical analyses of fluid recovered after the interior of bladders were washed with saline showed no evidence for the occurrence of surfactant that might be responsible for maintaining the air-liquid interface.

• ALGAE
• /
• v.34 no.3
• /
• pp.199-216
• /
• 2019

Platysiphon verticillatus and Punctaria glacialis are synonymized by mainly on the basis of shared genes, nine identical sequences. Our hypothesis is that synonymy is erroneous. We posit the many differences of biological features between the two species, their ecological preferences, and occurrences do not support synonymy. Arcticophycus (nov. gen.) is described and contains the new combination Arcticophycus glacialis. Asexual, vegetative, life histories are proposed. Novel reproductive structures are described including previously unknown features of thallus development in the life history of both species. Discovery of the novel Platysiphon cyst, and dual sporangia types in Arcticophycus, is critical in establishing a probable strategy for survival through the Arctic winter for each annual species. Pl. verticillatus is erect, tubular, ovoid to circular in X sections, flaccid, non-parenchymatous, light brown, 10-15 cm high with distinctive photosynthetic hairs in clusters or whorled on the upper one third of the thallus. A. glacialis is erect, planar, robust, parenchymatous, dark brown and hairs absent. The Halosiphon clade is named, consisting of four genera: Halosiphon, Platysiphon, Arcticophycus, and Stschapovia. Occurrence of these genera is identified. Emended are the genus Platysiphon, the family Platysiphonaceae and the order Stschapoviales.

• ALGAE
• /
• v.38 no.1
• /
• pp.23-38
• /
• 2023

Accurately identifying species is the basis of all biological studies. There has been much confusion in the identification of Grateloupiacean species, which have finely pinnate gross morphology similar to Grateloupia filicina (the type species of the family). The objective of this study was to comprehensively investigate species identification and distribution of G. filicina-like species in the Northwest Pacific, based on the rbcL sequences. A total of 118 specimens from 78 sites in Korea and Japan were collected from 2001 to 2021 and analyzed for their rbcL sequences. Additional 341 sequences downloaded from the GenBank were included in our comprehensive dataset. Based on these sequences, we documented the nomenclatural history and geographical distribution of the species, and commented on the application of species name. G. asiatica was the most abundant G. filicina-like species in the Northwest Pacific, and its high degree of morphological variation caused many misidentifications. In particular, G. dalianensis, G. serra, and G. variata require reconsideration of their conspecificity with G. asiatica using more specimens from China. By contrast, G. oligoclora was presumed to be a heterotypic synonym of G. subpectinata. The occurrence of G. acuminata, G. ramosissima, and G. livida in Korea resulted from misidentifications with other species.

• Korean Journal of Environmental Biology
• /
• v.27 no.3
• /
• pp.252-260
• /
• 2009

The summer algal flora and community of 9 islands in Dadohae National Park, southwestern coast of Korea, were investigated from June to September 2008. A total of 81 species (13 green, 22 brown and 46 red algae) of marine algae were identified. Among 9 islands, the number of species observed was the highest as 65 species at Jindo and the least as 37 species at Hongdo. The dominant species were Enteromorpha compressa, Ulva pertusa, Sargassum thunbergii, Gelidium amansii, Caulacanthus okamurae, Gloiopeltis furcata, and Symphyocladia latiuscula. The algal zonation of intertidal zone was figured out by Gloiopeltis furcata, Ishige okamurae, Caulacanthus okamurae-Enteromorpha compressa, Sargassum thungergii-Gelidium amansii, Symphyocladia latiuscula from upper to lower zone. The flora investigated could be classified into six functional groups such as coarsely branched form (38.1%), filamentous form (24.7%), sheet form (11.3%), thick leathery form (13.9%), jointed calcarious form (6.3%) and crustose form algae (5.7%). R/P and (R+C)/P values were 2.2 and 2.8, respectively. A cluster analysis of species occurrence was suggested that the number of marine algal species was different from greatly among the sampling sites.

• Journal of environmental and Sanitary engineering
• /
• v.10 no.1
• /
• pp.45-65
• /
• 1995

Seasonal occurrences and dynamics on the freshwater algae were examined in the upstream of the Yongsan river system with the Kwangju service water area from 1993 to 1994. Three hundred and three taxi were totally collected and composed of 6 classes, 15 orders, 7 suborders, 31 families, 74 genera, 248 species, 48 varieties and 7 forma. Compositions in each algal class were divided in 136 taxi of Chlorophyceae(44.8% ), 109 taxi of Bacillariophyceae(36.0% ), 30 taxa of Cyanophyceae(10.1% ), 21 taxa of Euglenophyceae(6. 9% ),4 taxi of Chrysophyceae(1.3% ) and 3 taxa of Dinophyceae(1.0% ). The occurrence of taxa was a markedly decrease(-62) between summer and autumn, the critically increase(+43) between spring and summer. And also, it was indicated that the high frequency of taxa in summer, but the high standing biomass In winter in spite of low taxi. In general, it has much algal biomass in station 9 and 10, but low in station 4, 5 and 11, relatively. Through this survey, the major dominant taxa in algal biomass, Microcystis aeruginosa, Melosira varians, Synedra ulna and Navicula cryptocephala, they were all above 2.1×10$^{6}$ce11s/1, 13.2% of totals. There are about 10% of new emigrated taxa by season and they showed a remarkable succession. We may suggested that this system was well sustained for the habitat of freshwater algal community with low dominance and high diversity. Twenty three of nuisance algae including of Microcystis aeruginosa, Peridinium willei and Anabaena flos-aquae were distributed as if had low appearance. Of course, many of them were saprobiontic taxa, extraordinary growttung groups depend on organic loading in water system and also it was not showed severe algal blooming phenomenon.