• Title/Summary/Keyword: biological environmental characteristics

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Newly recorded sea star Henricia oculata(Asteroidea: Spinulosida: Echinasteridae) in the East Sea, Korea

  • Ubagan, Michael Dadole;Shin, Sook
    • Korean Journal of Environmental Biology
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    • v.38 no.4
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    • pp.563-566
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    • 2020
  • Henricia specimens were collected using fishing nets from the East Sea of Korea. The specimens were identified as Henricia oculata Pennant, 1777, belonging to the family Echinasteridae of the order Spinulosida. This species can be distinguished from other Henricia species by broad arms (R/r=4-4.1), rough skin, a thick arm base, three to nine minute delicate abactinal spines, and inferomarginal plates reniform in shape. This species superficially resembles H. pachyderma in its body size and wide papular areas but differs mainly in the number of papulae and abactinal spines, and the shape and arrangement of the inferomarginal plates. To date, two genera of Echinasteridae, Aleutihenricia and Henricia, with a total of 13 species, have been reported in Korea. The morphological characteristics of H. oculata are described, and photographs are provided.

Two newly recorded sea stars of genus Henricia(Asteroidea: Spinulosida: Echinasteridae) from the East Sea, Korea

  • Michael Dadole Ubagan;Sook Shin
    • Korean Journal of Environmental Biology
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    • v.41 no.4
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    • pp.364-369
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    • 2023
  • Two newly recorded sea stars, Henricia densispina (Sladen, 1879) and H. reniossa asiatica Djakonov, 1958, collected from the East Sea of Korea using fishing nets, were described in this study. Morphologically, H. densispina is characterized by the shape (sub-triangular) similarity of the intermarginal plates to the superomarginal plates. Henricia reniossa asiatica Djakonov, 1958, has long and slender arms (R/r=7.2-9.1); clustered abactinal paxillae with 3-13 abactinal spinelets; a denuded abactinal skeleton made up of crescentic, elongated cross-shaped, the presence of small ossicles that divided the papular areas; and an adambulacral armature comprised of 14-17 spinelets. This study provides the first occurrence of H. densispina and H. reniossa asiatica in the Korean fauna and a detailed morphological description of these species' key characteristics is provided.

A Study on the Releasing Characteristics of Organic Matter and Heavy Metals and Changes of Dissolved Oxygen Concentration during Sediment Resuspension (퇴적물 재부유에 따른 유기물과 중금속 용출 및 용존산소량 변화 특성에 대한 연구)

  • Kang, Seon Gyeong;Lee, Han Saem;Lim, Byung Ran;Rhee, Dong Seok;Shin, Hyun Sang
    • Journal of Korean Society on Water Environment
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    • v.37 no.1
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    • pp.1-9
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    • 2021
  • The depletion of dissolved oxygen (DO) in urban streams has a profound effect on the aquatic ecosystem; however, the change in DO by resuspension of sediments and the cause have not been sufficiently investigated. In this study, the physicochemical properties (particle size, and the content of organic and heavy metals) of the sediments of an urban stream (Anyang Stream) and the characteristics of water quality changes (DO, dissolved organic carbon (DOC), dissolved nitrogen (DN), sediment oxygen demand (SOD), and adenosine triphosphate (ATP)) by sediment resuspension were investigated. The sediment content of fine particles (< 0.2 mm) increased from 36.7% to 52.7% from the upstream to the downstream, and the contents of heavy metals and organic matter of the sediment were also higher towards the downstream. The depletion of DO by resuspension was observed in the sediment at the downstream sites (P8, P9), where the fine particle content was high, and biological SOD (BSOD) was more than 88% compared to the total SOD. The increase in BSOD coincided with the increase in ATP. It was also confirmed that the depletion of DO could increase the amount of heavy metals (such as Fe, Mn, and Pb) released from the sediment. Based on the above results, it can be concluded that resuspension of sediments induces rapid water quality changes and may cause accidents, such as fish mortality, during rainfall, and such a water quality effect can be more pronounced in sediments with a high content of fine particles and organic matter and high biological activity.

Degradation of BTX by Klebsiella gr. 47 in the Biological Wastewater Treatment (Klebsiella gr. 47을 이용한 생물학적 폐수처리에서 BTX 분해 특성)

  • 염승호;최석순
    • Journal of Environmental Science International
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    • v.7 no.3
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    • pp.393-400
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    • 1998
  • A microorganism, Klebsiella gr. 47, capable of degrading BTX(benzene, toluene and xylene) was isolated from oil-contaminated soil and its characteristics of BTX degradation were investigated. When benzene and toluene were fed to Klebstella gr. 47 simulataneously, they showed competitive ingibition. The degradation rate of xylene was enhanced as much as 3 times when xylene was fed with benzene or toluene. Degradation rate of benzene and toluene was also enhanced by cocultured with Alcaligenes xylosoxidans. When benzene-adapted microorganism was used, each BTX compound was degraded efficiently within 5 hours.

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Description of Spheropistha melanosoma Yaginuma, 1957 (Araneae: Theridiidae) from Korea

  • Sue Yeon Lee;Jung Sun Yoo;Chang Moon Jang;Seung Tae Kim
    • Korean Journal of Environmental Biology
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    • v.41 no.1
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    • pp.14-17
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    • 2023
  • A male Spheropistha melanosoma Yaginuma, 1957 from Korea in the family Theridiidae Sundevall, 1833 is described with measurements and morphological photos of the diagnostic characteristics. This species was collected with a sweep net around arable lands in a mountainous mixed forest during the investigation of spider fauna on Ulleungdo Island in 2019.

A Study of Comparison of outflow characteristics of pollutants by rainfall event of forest area near Juam lake basin (주암호 유역의 강우사상에 따른 오염물질의 유출특성)

  • Kim, Nam-Joung;Shin, Dae-Yewn
    • Journal of environmental and Sanitary engineering
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    • v.22 no.4
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    • pp.87-104
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    • 2007
  • The objective of this study is to estimate the load of pollutants caused from the forest area among non-point pollutants within the Juam lake. The surveyed forest area was classified into broad-leaved, conifer, mixed and herbage area by forest tree type. Water quality and flux were investigated under rainfall and non-rainfall, respectively. Then, pollutant loading was evaluated by using the values of unit pollutant loading factor of each point and area of forest zone. Water quality analysis results of runoff by forest tree types were as follows. - Annual BOD, $COD_{Mn}\;and\;COD_{Cr}$ concentration of runoff in conifer area was high, and particle and biological recalcitrant compounds were flowed highly. - SS, T-N and T-P concentration was high in runoff from broad-leaved area, and biological degradable compounds was flowed. - Water quality of water from valley was maintained good under non-rainfall and could be utilized as fresh drinking water. Through water quality standard investigation, a countermeasure establishment was necessary to secure a good quality of drinking water - BOD, $COD_{Mn},\;and\;COD_{Cr}$ concentration of Bo-sung river was higher 1.5 times than other 2 streams, and because of high T-N, and T-P concentration in Songgwang stream, the management for this was necessary.

Seven Unrecorded Indigenous Fungi from Mudeungsan National Park in Korea

  • Minseo Cho;Sun Lul Kwon;Young Mok Heo;Young Min Lee;Hanbyul Lee;Changmu Kim;Byoung Jun Ahn;Jae-Jin Kim
    • Mycobiology
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    • v.50 no.4
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    • pp.203-212
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    • 2022
  • Fungi act as important decomposers in the forest environment. They recycle essential nutrients, promote plant growth through mycorrhizal relationships, and act as food for small animals. Samples of 265 indigenous fungal species were collected from Mudeungsan National Park in 2020. These species were identified based on morphological, molecular, and phylogenetic analyses using the internal transcribed spacer (ITS), nuclear large subunit rRNA (LSU), and RNA polymerase II second largest subunit (rpb2) regions. Subsequently, seven species were identified as unrecorded species in Korea: Cordyceps cicadae, Dentocorticium bicolor, Hymenochaete nanospora, Physisporinus crataegi, Rigidoporus piceicola, Russula raoultii, and Scutellinia crinita. This study reveals their detailed macro- and microscopic morphological characteristics with phylogenetic trees to report them as unrecorded species in Korea.

The Development of Exposure Assessment Tools for Risk Assessment of Volatile Organic Compounds (VOCs의 위해성 평가를 위한 노출분석 방법 연구)

  • Jo, Seong-Joon;Shin, Dong-Chun;Chung, Yong;Lee, Duck-Hee;Breysse, Patrick N.
    • Environmental Analysis Health and Toxicology
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    • v.17 no.2
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    • pp.147-160
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    • 2002
  • Volatile organic compounds (VOCs) are an important public health issue in Korea and many important questions remain to be addressed with respect to assessing exposure to these compounds. Because they are ubiquitous and highly volatile, special techniques must be applied in their analytic determination Valid Personal exposure assessment methods are needed to evaluate exposure frequency, duration and intensity, as well as their relationship to personal exposure characteristics. Biological monitoring is also important since it may contribute significantly in risk assessment by allowing the estimation of effective absorbed doses. This study was on ducted to establish the environmental measurement, personal dosimetry and biological monitoring methods for VOCs. These methods are needed to compare blood, urinary and exhalation breath VOC levels and to provide tools for risk assessment of VOC exposure. Passive monitors (badge type) and a active samplers (trap) for the VOCs collection were used for air sampling. Methods development included determining the minimum detectable amounts of VOCs in each media, as well as evaluating collection methods and developing analytical procedures. Method reliability was assessed by determining breakthrough volumes and comparing results between laboratories and with other methods. A total capacity of trap used in this study was 60ι. Although variable by compound, the average breakthrough was 20%. Also, there was no loss of compounds in trap even if keep for 45 day in -7$0^{\circ}C$. The recovery of active and passive methods was 69% ~ 126% and method detection limit was 0.24 $\mu\textrm{g}$/trap and 0.07 $\mu\textrm{g}$/badge. There was no statistical difference (P > 0.05) between active and passive methods.

Distribution Characteristics of and Ecological Information on Benthic Macroinvertebrates in the Hwapocheon Stream (화포천의 저서성 대형무척추동물 분포특성과 생태학적 정보)

  • Bae, Seong-Woo;Hwang, Tae-Won;Yoon, Chun-Sik;Hong, Sung-Jin;Cheong, Seon-Woo
    • Journal of Environmental Science International
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    • v.31 no.2
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    • pp.149-169
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    • 2022
  • Hwapocheon stream is located in Gimhae-si, Gyeongsangnam-do, and a part was declared a protected wetland area in 2017. In 2020 and 2021, we investigated the community structure of benthic macroinvertebrates of the Hwapocheon stream to provide ecological information for the management of the wetland. As a result, 4 phyla, 6 classes, 20 orders, 51 families, 83 species, and 2,621 individuals of benthic macroinvertebrates were identified. The average indices of diversity, richness, and evenness were the highest in the midstream area, whereas the highest average index of dominance was observed upstream. Seven biological water quality evaluations based on the distribution of benthic macroinvertebrates showed that the Biological Monitoring Working Party was an extremely suitable method for environmental evaluation of the Hwapocheon stream. Regarding functional feeding groups, the number of species of predators and gathering-collectors was the highest, and considering habitual dwelling groups, the number of species of clingers and sprawlers was the highest. The species number of Odonata, Hemiptera, and Coleoptera increased toward the downstream area, whereas the community loss index was the highest upstream. We also investigated relative resistance and resilience based on the distribution of aquatic insects and found that community stability was the highest downstream, whereas the lowest upstream.

Comparison of physical characteristics of eggs of Trachemys scripta elegans, Pseudemys concinna, and Mauremys reevesii (붉은귀거북(Trachemys scripta elegans)과 리버쿠터(Pseudemys concinna), 국내종 남생이(Mauremys reevesii) 간 알의 외형적 특징 비교)

  • Seung-Ju Cheon;Choong-Ho Ham;Seung-Min Park;Ju-Hee Bae;Ju-Hee Lee;Seong-Ik Jo;Suk-Jin Cheon;Ha-Cheol Sung
    • Korean Journal of Environmental Biology
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    • v.41 no.2
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    • pp.138-144
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    • 2023
  • The main factor of biodiversity decline in major biological populations around the world is invasion of alien species. To protect native species, it is necessary to manage alien species. Recently, to eradicate ecosystem disturbance caused by alien species in Korea, many efforts have been made to capture individuals using nets and purchase captured individuals. However, there is no standard for classifying species due to the form of nest site or external characteristics of eggs of freshwater turtles. Thus, Mauremys reevesii eggs might be discarded due to mistaking as eggs of alien turtles. Based on more data, this study aims to compare and analyze external differences among eggs of Trachemys scripta elegans, Pseudemys concinna, and M. reevesii and use them as reference materials in the process of eradicating alien turtles. This study measured characteristics of eggs of the three turtle species. As a result of comparison, all variables of external characteristics of alien turtles and M. reevesii eggs showed significant differences. The shape of egg was also different, with eggs of T. scripta elegans and P. concinna showing a bicone shape and those of M. reevesii showing an ellipsoid shape. In conclusion, based on results of previous studies and the present study, eggs of M. reevesii, T. scripta elegans, and P. concinna are different in shape and structure. Thus, it is possible to distinguish between M. reevesii and invasive alien turtle using their eggs.