• Journal of Life Science
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• v.22 no.10
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• pp.1286-1294
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• 2012

Biological assessments of the macrobenthos community were carried out in the Seomjin River from May 2009 to November 2010. Fishes from 106 species belonging to 24 families and 10 orders were collected from the survey sites. Locational dominant species differed among sites, and the numbers of species and individuals differed depending on site, although six sites were not significantly different on the same survey dates. Across sites, the average number of species was 38.3, ranging from five at site 1 to 66 at site 2 in May 2009. Site 2 had the highest number of species on November 2009, while site 3 had the lowest. Arthropods dominated the macrobenthic community at species (63.2% May) and individual (60.9% November) levels. DO, BOD, and COD were shown to have the greatest effect on the numbers of macrobenthos. Peaks in the diversity index trended downwards from upstream to downstream sites.

• Korean journal of applied entomology
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• v.61 no.1
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• pp.15-28
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• 2022

Neuropeptides produced in neurosecretory cells are the largest group of insect hormones. They regulate various physiological functions, such as fat body homeostasis, feeding, digestion, excretion, circulation, reproduction, metamorphosis, and behavior throughout all life stages. The PRXamide peptide family (X, a variable amino acid) is a well-characterized neuropeptide component with a common amino acid sequence, PRXamide (NH₂), at the C-terminal end conserved across Insecta. The PRXamide peptides are classified into three subfamilies, each having diverse biological roles in insects: (1) pyrokinin (PK) includes the pheromone biosynthesis activating neuropeptide (PBAN) and the diapause hormone (DH), (2) the capability (CAPA) peptides, and (3) the ecdysis-triggering hormone (ETH). PBAN as a member of PK subfamily was first identified to stimulate pheromone biosynthesis in moths three decades ago. Since then, PBAN peptides have been extensively studied by various research groups from a broad spectrum of arthropods. In this paper, we briefly review insect PBAN molecules with emphasis on gene structure and expression, signal transduction, physiological mechanism in sex pheromone biosynthesis, and application for pest management.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.34 no.5
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• pp.493-501
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• 2001

A study on the community structure of macrobenthos was accomplished around Kadugdo, a south coast of Korea. Sampling was performed bimonthly using a Smith-McIntyre grab ($0.05 m^2$) at ten stations from January to November, 1998. A total of 260 species was sampled with mean density of $1,729 ind./m^2$and biomass of $154.7 gwwt./m^2$during the study periods. Of these species, there were 96 species of arthropods ($37.0\%$), 89 species of annelids ($34.2\%$), 45 species of molluscs ($17.3\%$) and 30 species of others ($11.5\%$). Annelids were density-dominant faunal group with a mean density of $1,263 ind./m^2$which occupied $73.0\%$ of the total individual of benthic animals. Molluscs were represented as biomass-dominant faunal group with a mean biomass of $99.5 gwwt./m^2$ ($64.3\%$ of total biomass). The density-dominant species were a bivalvia Theora fragilis ($194 ind./m^2$) and five species of polychaetes, Lumbrineris longifolia ($177 ind./m^2$), Chaetozone setosa ($150 ind./m^2$), Sternaspis scutata ($116 ind./m^2$), Sigambra tentaculata ($106 ind./m^2$) and Hemipodus yenourensis ($94 ind./m^2$). And major biomass-dominant species was a bivalvia Ruditapes philippinarum ($45.6 gwwt./m^2$). Clustering analysis showed that the study area could be divided into two station groups and three stations: southwestern part of Kadugdo effected on Chinhae Bay, fisheries farming area and eastern part of Kadugdo effected on Nakdong River estuary.

• The Korean Journal of Malacology
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• v.18 no.1
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• pp.41-52
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• 2002

This study was performed to know the vertical distribution pattern and community structure of intertidal invertebrates at 9 sampling stations near Songacksan area located in Jeju Island from June 2000 to May, 2001. A total of 104 benthic invertebrate species was recorded during the survey period and it was composed of 50 families, 25 orders, 12 classes and 6 phyla. Among them, the most highest species richness was observed in the mollusks comprising 66.3% (69 species) and the next one in the arthropods showing 16.3% (17 species). Species diversity was largely different depending on their vertical distribution, revealing much higher in the lower intertidal zone than in the middle or upper zone, while there were no distinct differences between sampling stations. The dominant species were Nodilittorina exigua, Littorina brevicula, Pollicipes mitella mitella and Nerita japonica in the upper zone, Monodonta neritoides, Lunella coronata coreensis and Nerita japonica in the middle zone and Notoacmea schrenckii, Omphalius nigerimus, Purpura clavigera and Chlorostoma argyrostoma lishckei in the lower zone. The macrobenthic fauna surveyed could be divided into two groups based on their species similarities between sampling stations but their differences were not distinctive.

• The Korean Journal of Malacology
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• v.27 no.3
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• pp.229-246
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• 2011

This study was performed to know and compare the community structures of macrobenthic invertebrates of eight fishing grounds in the coastal waters of Jeju Island from September to October 2008. A total of 166 species was identified. Mollusks comprised 77 species (46.4%); Arthropods 24 (14.5%), Cnidarians 18 (10.8%); Poriferans 16 (9.6%); and the others including Echinoderms 33 (17.7%). Density and biomass were estimated to be 6,905 ind./$m^2$ and 113,100.7 gwwt/$m^2$, respectively. Gastropods was the most dominant taxon in terms of abundance (3,311 ind./$m^2$) and number of species as well, and Gastropods was predominant in biomass (55,789.2 gwwt/$m^2$). The dominant species were Omphalius pfeifferi, Astralium haematragum, Turbo cornutus, Ergalatax contraacta, Lithophaga cura, Anthocidaris crassispina, Herdmania monus in 5-15 m. Based on the cluster analysis, the study area could be divided into two station groups. The biodiversity, evenness and richness index appeared as follows: H' = 1.59-2.95, E' = 0.38-0.87, R = 3.3-10.4. The dominance index were highest in Daepo and lowest in Woljeong.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.33 no.6
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• pp.572-580
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• 2000

Community structure of macrobenthos was studied in Chinhae Bay, a southern coastal area of Korea. Sampling was conducted bimonthly using a Smith-McIntyre grab ($0.05 m^2$) at eight stations from January to November, 1998. A total of 237 species were sampled. It was comprised of annelids ($80 spp. 33.8{\%}$), arthropods (80 spp.), molluscs (47 spp.), echinoderms (16 spp,) and others, Mean density of individual was $1,939 ind./m^2$ and mean biomass was $171.6 gwwt/m^2$. Annelids were a density-dominant faunal group with a mean density of $1,533 ind./m^2$ which occupied $79.0{\%}$ of the total individual of benthic animals. Molluscs were represented as a biomass-dominant group with a mean biomass of $95.9 gwwt/m^2$ ($55.9{\%}$ of total biomass). The major density-dominant species were a bivalve Theora fratilis ($110 ind./m^2$) and five species of polychaetes, Lumbrineris longifolia ($417 ind./m^2$), Chaetozone setosa ($145 ind./m^2$), Sigambra tentaculata ($128 ind./m^2$), Cirratulus cirratus ($128 ind./m^2$), and Paraprionospio pinnata ($103 ind./m^2$). Cluster analysis showed that the study area could be divided into two station groups and two stations. According to the feeding guild of polychaetes, four feeding guilds were found, and the major ones were surface deposit-feeders, burrowing deposit-feeders, surface suspension-feeders, carnivore.

• The Korean Journal of Malacology
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• v.32 no.4
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• pp.297-328
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• 2016

This study was performed to know and compare the community structures of macrobenthic invertebrates of five fishing grounds in the coastal waters of Jeju Island from 2013 to 2015. A total of 629 species was identified. Molluscans comprised 282 species (44.8%), Arthropods 88 (14.0%), Poriferans 61 (9.7%), Bryozoans 52 (8.3%) and the others including Cnidarians 51 (8.1%). Density and biomass were estimated to be $71,007ind./m^2$ and $599,208.0gwwt/m^2$, respectively. Gastropods was the most dominant taxon in terms of abundance ($24,625ind./m^2$ ) and number of species as well, and Gastropods was predominant in biomass ($190,789.0gwwt/m^2$). The dominant species were Omphalius pfeifferi, Astralium haematragum, Musculus viridulus, Halosydna brevisetosa, Phascolosoma scolops, Herdmania monus in 5-20 m. Based on the cluster analysis, the study area could be divided into five station groups. The biodiversity, evenness and richness index appeared as follows: H' = 4.28-4.64, E' = 0.74-0.79, R = 33.17-35.45. The dominance index were highest in Sagye and lowest in Sinhung.

• Korean Journal of Environment and Ecology
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• v.26 no.1
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• pp.39-45
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• 2012

To explore on the defense strategies against hervivory of 67 broadleaved tree species, morphological characteristics of the leaf, leaf domatia structure and the number, herbivores insects and mites on the leaves, collected from the trees growing in Taean-gun, Chuncheongnam-do were investigated. 46 broadleaved tree species(68.7%) had the domatia structures, and 21 species including Quercus salicina and Magnolia grandiflora did not. 31 species including Juglans mandshurica and Carpinus laxiflora reveals tuft type, 12 species including Quercus dentata and Corylus heterophylla reveals pocket+tuft type, and 2 species, Sorbus alnifolia and Prunus yedoensis does pocket type, and Viburnum odoratissimum var. awabuki does pouch type. Domatia number per leaf proves the highest figures, 23.4/leaf for Quercus dentata. Plant defense strategies using leaf lower-surface trichomes of Magnolia grandiflora reveals dense villous, those of Populus alba and Vitis vinifera reveals dense pilose, that of Elaeagnus umbellata does dense scaly hairs, that of Pueraria lobata does dense strigose. Plant defense strategies using extrafloral nectaries were adapted 23 tree species(34.3%). Observed examples are Prunus tomentosa, Ficus carica, Viburnum dilatatum and Carpinus laxiflora. Predatory mites were observed on the leaves of 40 tree species(59.7%), and mean values of predatory mites was highest values 23.4/leaf in Quercus dentata. Minute arthropods destroying the leaf of broadleaved trees. are such as Periphyllus californiensis, P. viridis, Diaspididae sp., gall mites, thrips, and total numbers observed were odered gall mites, Diaspididae sp., aphids and thrips. Natural enemies of these hervivores arthropods are such as predatory mites, Chilocorus rubidus, Coccinella septempunctata and the nymph, Aphidius ervi. These results indicate that defense strategies including protective mutualisms may be frequent in the temperate broadleave trees.

• Korean journal of applied entomology
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• v.34 no.3
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• pp.256-265
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• 1995

The effect ground-cover weeds on the occurrence of apple pests and their natural enemies was studied in an apple orchard in Ahnsung, Kyung-gi do during seasons of 1993 and 1994. The major apple pests and their parasitoids and predators were surveyed on the apple tree canopy in tow experimental plots; a weed-free lot where all weeds were removed by herbicide treatment, and a mowed plot where weeds were allowed restrictly by cutting with an asickle. Also, a sweep net sampling was taken from ground-cover weeds in the mowed plot. There were no significant differences in the abundance of mite and aphids between two plots, although mite densities tend to be lower in the mowed plot. The apple leaf miner, Phyllonorycter ringoniella, was significantly fewer in the mowed plot,. The densities of natural enemies of mites and aphids were slightly higher in the mowed plot. The parasitism of apple leaf miner in the mowed plot was 6~10% and 20~25% higher than that in the weed-free plot in 1993 and 994, respectively. Several natural enemies such as Apanteles kuwayamai (Braconidae), Orius sauteri (Anthocoridae), Chrysopa sp. (Chrysopidae), coccinellidae, and Eulophidae were collected both from weeds and the apple trees, However, potential apple pests were not observed on weeds. The development of insect community on the apple tree canopy was restricted by the pesticide spray on apple trees, while the insect community on weeds was maintained without significant destruction by pesticides spray on apple trees. Consequentely, the ground-cover weeds under apple trees affected occurrences of apple pests and their natural enemies in apple trees. te specialist natural enemies such as apple leaf miner's parasitoids dispersed from weeds to the apple canopy and affected apple leaf miner density significantly. However, generalist predators that have preys available on weeds stayed on weeds, hence their control effects for mites and aphids on the apple canopy were low.