• Proceedings of the Korea Society of Environmental Toocicology Conference
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• 1997.12a
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• pp.47-71
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• 1997

• Parasites, Hosts and Diseases
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• v.59 no.5
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• pp.489-496
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• 2021

Ticks can transmit pathogenic bacteria, protozoa, and viruses to humans and animals. In this study, we investigated the microbiomes of Haemaphysalis longicornis according to sex and life stages. The Shannon index was significantly higher for nymphs than adult ticks. Principal coordinates analysis showed that the microbiome composition of female adult and male adult ticks were different. Notably, Coxiella-like bacterium (AB001519), known as a tick symbiont, was found in all nymphs and female adult ticks, but only one out of 4 male adult ticks had Coxiella-like bacterium (AB001519). In addition, Rickettsia rickettsii, Coxiella burnetii, and Anaplasma bovis were detected in this study.

• Parasites, Hosts and Diseases
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• v.48 no.4
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• pp.351-353
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• 2010

To investigate the population densities of potential malaria vectors, Anopheles species were collected by light traps in malaria endemic areas, Paju and Gimpo, Gyeonggi-do of Korea. Five Anopheles Hyrcanus sibling species (An. sinensis, An. pullus, An. lesteri, An. kleini, and An. belenrae) were identified by PCR. The predominant species, An. pullus was collected during the late spring and mid-summer, while higher population consists of An. sinensis were collected from late summer to early autumn. These 2 species accounted for 92.1 % of all Anopheles mosquitoes collected, while the other 3 species accounted for 7.9%. Taking into account of these population densities, late seasonal prevalence, and long-term incubation period (9-13 months) of the Korean Plasmodium vivax strain, An. sinensis s.s is thought to play an important role in the transmission of vivax malaria in the study areas.

• Korean Journal of Environmental Agriculture
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• v.38 no.3
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• pp.139-144
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• 2019

BACKGROUND: Epigeic arthropods participate in ecological functions as predators, decomposers and herbivores. The purpose of this study was to investigate the responses of some dominant arthropods in rice fields to different forms of agricultural land management. METHODS AND RESULTS: The abundance of microarthropods was compared between rice fields and uplands in the non-growing season. Collembola, Oribatida and Mesostigmata were more abundant in the upland fields than in the paddy fields. The community composition and diversity of epigeic arthropods were compared between fallow and rice fields. The total abundance and species richness of spiders and ground beetles were not significantly different in the two types of agricultural fields. The abundance of Arctosa kwangreungensis was greater in fallow fields than in cultivated fields. The community structure of arthropods was compared between paddy fields with and without barley. The cropping system altered the community composition of spiders but not their biodiversity. Barley cultivation increased the abundance of ground beetles but decreased that of spiders. We suggest that this contrast was partly due to the availability of plants that provided shelter and food for ground beetles. CONCLUSION: These results show that soil use intensity and cropping system alter the community composition of epigeic spiders and ground beetles. This could result in ecosystem-level alterations with respect to the control of pests and weeds. Our results also suggest that biodiversity of ground-dwelling arthropods may not increase during short fallow periods.

• Parasites, Hosts and Diseases
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• v.58 no.5
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• pp.537-542
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• 2020

Cockroaches inhabit various habitats, which will influence their microbiome. Although the microbiome can be influenced by the diet and environmental factors, it can also differ between species. Therefore, we conducted 16S rDNA-targeted high-throughput sequencing to evaluate the overall bacterial composition of the microbiomes of 3 cockroach species, Periplaneta americana, P. japonica, and P. fuliginosa, raised in laboratory for several generations under the same conditions. The experiments were conducted using male adult cockroaches. The number of operational taxonomic units (OTUs) was not significantly different among the 3 species. With regard to the Shannon and Pielou indexes, higher microbiome values were noted in P. americana than in P. japonica and P. fuliginosa. Microbiome composition was also evaluated, with endosymbionts accounting for over half of all OTUs in P. japonica and P. fuliginosa. Beta diversity analysis further showed that P. japonica and P. fuliginosa had similar microbiome composition, which differed from that of P. americana. However, we also identified that P. japonica and P. fuliginosa host distinct OTUs. Thus, although microbiome compositions may vary based on multiple conditions, it is possible to identify distinct microbiome compositions among different Periplaneta cockroach species, even when the individuals are reared under the same conditions.

• Animal Systematics, Evolution and Diversity
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• v.26 no.3
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• pp.203-216
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• 2010

Adult chironomids were collected at Dangsan-ri, Muju-eup, Muju-gun, Jeollabuk-do on 5 September 2008, 22 May 2009 and 28 August 2009. A total of 221 specimens belong to the genus Polypedilum Kieffer from 1,113 adult midges collected were morphologically examined, and 16 Polypedilum species were identified. One species is new (Polypedilum dangsanensis Ree et Jeong sp. nov.) and eight species are newly recorded in Korea (P. asakawasense, P. convictum, P. decematogutatus, P. japonicum, P. kamotertium, P. pullum, P. serugense, and P. unifascium). These nine species are described with illustrations. Polypedilum nubifer was the most frequently collected species, consisting of 25.8% of the Polypedilum samples.

• Parasites, Hosts and Diseases
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• v.59 no.1
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• pp.61-65
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• 2021

Diarrheal disease is the second leading cause of mortality and morbidity in children under 5 years old worldwide, and is the most common cause of malnutrition in sub-Saharan Africa. In Rwanda, diarrhea is the third leading cause of death in children under 5 years old. This study examined the association between sociodemographic factors and diarrhea in children under 5 years using the data of 7,474 households in the 2014-2015 Rwanda Demographic and Health Survey. Overall prevalence of diarrhea in this study was 12.7% in children. An increased risk for diarrhea was found for children aged 12-23 months (odds ratio (OR)=4.514), those with a low economic status (OR=1.64), those from the Western province (OR=1.439), those with poorly-educated mothers (OR=5.163), and those with families engaged in agricultural activities (OR=1.624). In conclusion, sociodemographic factors significantly affect the risk of developing diarrhea in children under 5 years in Rwanda. Designing and implementing health education promoting awareness of early interventions and rotavirus vaccination are essential to reduce diarrheal diseases for the Rwandan community.

• Korean journal of applied entomology
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• v.36 no.3
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• pp.231-236
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• 1997

Arthropods of 3 Classes, 19 Orders and 58 Families were collected by the enticing band from the trunk of apple trees in winter in Kyongbuk province. The two spotted spider mite, Tetranychu.v urricae Koch, was dominant species with 53.0%, followed by Eriosomtr lanigerutn Hausmann. 16.7%. Oribatida 13.3% and Collembola 9.3%. Of those, herbivores were majority, followed by some decomposers and few natural enemies. Arthropods of 2 Classes, 12 Orders and 17 Families were observed from the fallen leaves. T. urric,ae 63.1% was dominant, followed by Collembola 13.797~ and other Arthropods. While 2 Classes, 9 Orders and 18 Families were investigated from the soil of apple orchards. They were collembola 37.9%. Oribatida 34.476, T. urticae Ih.l% and others in few numbers. Decomposers were majority, followed by herbivores and few natural enemies.

• Korean journal of applied entomology
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• v.60 no.1
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• pp.105-114
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• 2021

Ground-dwelling arthropods are important components in apple orchard providing beneficial ecological services of predation and decomposition as well as herbivory. Groundcovers are managed differentially in organic and conventional apple orchards influencing ground-dwelling arthropod assemblages. We conducted 3-year studies to assess the effects of orchard management relative to weed management on the abundance and diversity of ground-dwelling arthropods using pitfall trapping. Most arthropods were classified as higher taxonomical groups and functional feeding guilds, while carabid beetles were classified into species level. Coleoptera was the dominating taxon of all ground-dwelling arthropods. Abundance of herbivores and predators was significantly higher in organic apple orchards than conventional ones. Higher abundance and diversity of carabid beetles were found in organic orchards than in conventional orchards. The abundance of Araneae, Coleoptera, or carabid beetles was negatively correlated to weed management frequency. It was found that ground-dwelling arthropods were more influenced by weed management practices than the farming systems.

• Animal cells and systems
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• v.1 no.4
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• pp.577-581
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• 1997

Species diversity of subcortical arthropod communities were assessed in two tropical regions and two temperate regions. In the tropics, communities of subcortical arthropods were more diverse in La Selva, Costa Rica, than on Barro Colorado Island, Panama. Costa Rican communties yielses higher values of both Shannon and Simpson diversity indices than Panamanian communities. Compared to Panamanian communities, Costa Rican ones supported higher measures of both species richness and evenness. Between the two temperate regions, communities of subcortical arthropods in Korea scored consistently higher values of both Shannon and Simpson indices than the ones in eastern Massachusetts, U.S.A. When individual diversity components were compared, however, Korean communities yielded exceptionally high evenness measures but lower species richness than the communities in the U.S.A. Unusually high evenness values of Korean subcortical arthropods were due to extremely low population densities of all component species.