Showing papers by "Wonchoel Lee published in 2003"
TL;DR: The Tigriopus japonicus β-actin genes were amplified from genomic DNA by polymerase chain reaction (PCR) and cloned into pCRII vector and the phylogenetic implications inferred from the T. japoncius β- actin gene are discussed.
Abstract: The Tigriopus japonicus beta-actin genes were amplified from genomic DNA by polymerase chain reaction (PCR) and cloned into pCRII vector. Several clones of the T. japonicus beta-actin gene spanned 1662-1676 bp with gains or losses of some bases in intron 3 or 4 but they consisted generally of 5 exons and 4 introns with very high homology, implying polymorphism of this gene. The exon and intron boundaries were matched with the GT/AG rule. The T. japonicus beta-actin gene showed high homology to the fish (Rivulus marmoratus) and human genes, 99.2 and 98.4%, respectively at the amino acid sequence level. The phylogenetic implications inferred from the T. japoncius beta-actin gene are discussed.
13 citations
TL;DR: This new species is clearly distinguishable from its congeners with the combined characters of the short caudal ramus and its short ornamented seta V, two setae on the antennary exopod, and small rounded rostrum.
Abstract: A new interstitial copepod of the family Laophontidae was found in the samples from a sandy beach at Taean, west coast of Korea. This species was described and named as Quinquelaophonte koreana sp. nov. Present new species is clearly distinguishable from its congeners with the combined characters of the short caudal ramus and its short ornamented seta V, two setae on the antennary exopod, and small rounded rostrum. Q. koreana sp. nov. is the first record of Quinquelaophonte from the Northeast Asian coast.
11 citations
TL;DR: Three new species of Normanellidae are described from the Texas coast, Gulf of Mexico, with well-developed areolated patterns on the cephalothorax, six-segmented antennule and a smooth apical margin of the rostrum.
Abstract: Three new species of Normanellidae are described from the Texas coast, Gulf of Mexico. Normanella texana sp. nov. has limited areolated patterns on the cephalothorax, short P5 exopod and endopod, short caudal ramus and short caudal seta VI-V. Normanella brevispina sp. nov. is characterized by its relatively long caudal rami, and areolated rostrum. Normanella chanhoi sp. nov. has well-developed areolated patterns on the cephalothorax, six-segmented antennule and a smooth apical margin of the rostrum. N. texana belongs to the bolini -lineage, and N. brevispina to the minuta -lineage. Normanella chanhoi establishes a new lineage of its own.
10 citations
TL;DR: In this paper, surface temperature, salinity, density, and phytoplankton biomass (chi a) was measured in Kongsfjorden near Korean Arctic Station, Dasan, is a glacial fjord in the Svalbard archipelago, Arctic that is influenced by both Atlantic and Arctic water masses.
Abstract: Kongsfjorden near Korean Arctic Station, Dasan, is a glacial fjord in the Svalbard archipelago, Arctic that is influenced by both Atlantic and Arctic water masses. During the Arctic field season August 2002, surface temperature, salinity, density, and phytoplankton biomass (chi a) was measured in Kongsfjorden. A total of 15 surface samples were collected for the phytoplankton related measurements. Chl a values ranged from 0.08 to 1.4mg chi a (mean of 0.53mg chl a ) in the overall surface stations. The highest values of the chi a concentrations (> 1.0mg chi a ) were found near glacier in the northeastern part of Kongsfjorden. Nanoplanktonic () phytoflagellates were important contributors for the increase of the chi a. The nano-sized phytoflagellates accounted for more than 90% of the total chi a biomass in the study area. Surface temperatures and salinities ranged from 2.5 to (mean of ) and from 22.55 to 32.97 psu (mean of 30.16 psu), respectively. The physical factors were not highly correlated with phytoplankton distribution. The character of surface water due to down-fjord wind was highly similar to phytoplankton distribution. Drifting ice, freshwater, and semdiment inputs from large tidal glaciers located in the inner part of Konsfjorden create steep physico- and biogeochemical environmental gradients along the length of this ford. The glacial inputs cause reduced biodiversity biomass and productivity in the pelagic community in the inner fjord. Primary production of benthic and pelagic microalgae is reduced due to the limited light levels in the turbid and mixed inner waters. The magnitude of glacial effects diminishes towards the outer fjord. Kongsfjorden is an important feeding ground fer marine mammals and seabirds. Especially, seabirds play the largest energy intake and also export nutrients for primary production of the marine microalgae. Kongsfjorden has received a lot of research attention as a site for exploring the impacts of climate changes. Dasan Station in Kongsfjorden will be an important Arctic site for monitoring and detecting future environmental changes.
10 citations
TL;DR: The temporal dynamics of the meiofauna community in Marian Cove, King George Island were observed from January 22 to October 29 1996 and the temporal pattern of the community composition was most affected by the abundance dynamics of kinorhynchs and harpacticoids.
Abstract: The temporal dynamics of the meiofauna community in Marian Cove, King George Island were observed from January 22 to October 29 1996. Generally, 14 taxa of metazoan meiofauna were found. Nematodes were dominant comprising 90.12% of the community, harpacticoid 6.55%, and Kinorhynchs 1.54%. Meiofauna abundance increased monthly from January to May 1996, while varying in abundance after August 1996. Overall mean abundance of metazoan meiofauna was during the study periods, which is about as high as that found in temperate regions. Nematodes were most abundant representing . Mean abundance of harpacticoids, including copepodite and nauplius was by kinorhynchs . The overall abundance of other identified organisms was Other organisms consisted of a total of 11 taxa including Ostracoda , Polycheata , Oligochaeta , and Bivalvia . Additionally, protozoan Foraminifera occurred at the study area with a mean abundance of . Foraminiferans were second in dominance to nematodes. The dominant taxa such as nematodes, harpacticoids, kinorhynchs and the other tua were trained and extensively scattered in the map through the Kohonen network. The temporal pattern of the community composition was most affected by the abundance dynamics of kinorhynchs and harpacticoids. The neural network model also allowed for simulation of data that was missing during two months of inclement weather. The lowest meiofauna abundance was found in August 1996 during winter. The seasonal changes were likely caused by temperature and salinity changes as a result of meltwater runoff, and the physical impact by passing icebergs.
6 citations