수생태 환경 연구에 있어 안정동위원소의 활용과 전망

최보형,신경훈 한국수생태학회(구 한국하천호수학회) 2018 생태와 환경 Vol.51 No.1

광양만 주둥치(Leiognathus nuchalis)의 서식처 이동에 의한 먹이원 변동 파악을 위한 안정동위원소 분석기법 적용

최보형,조현빈,박기연,곽인실 한국어류학회 2020 韓國魚類學會誌 Vol.32 No.2

We investigated carbon and nitrogen isotope ratios (δ13C and δ15N) of the slipmouth Leiognathus nuchalis to reveal the effects of body size, feeding strategy and spatial distribution on the food resource utilization during the migration in the Seomjin estuary and Gwangyang Bay. The δ13C values of L. nuchalis caught in the Seomjin estuary where the salinity is lower than 30 psu were much lower than those in the deep-bay area of Gwangyang Bay. Such a spatial heterogeneity in δ13C values of the L. nuchalis clearly indicates active feeding within the estuarine habitat. In contrast, the δ15N values of L. nuchalis showed a consistency among sites, indicating that this species occupies identical trophic level across the whole area. The slipmouth distributed throughout the bay area, reflecting its euryhaline characteristics. However, the distribution pattern appeared to be separated according to body size into smaller individuals in the low-saline estuary and larger ones in the deep bay. Overall results support the plastic feeding strategy of the slipmouth from zooplanktonic (estuarine habitat) to epibenthic (deep-bay habitat) feeder during the migration between estuarine to deep-bay habitats. 섬진강 하구와 광양만에 서식하는 주둥치의 서식처 및 섭식 특성을 비교하기 위해 탄소 및 질소 안정동위원소 분석을 실시하였다. 주둥치의 탄소안정동위원소비 (δ13C) 값은 염분이 30 psu보다 낮은 섬진강 하구에서 채집된 개체에서 광양만에 비해 낮은 값이 나타났으며, 이는 섬진강 하구에서 채집된 주둥치가 해당 정점에서 섭식활동을 하고 있음을 의미한다. 이와 대조적으로, 채집된 주둥치의 질소안정동위원소비 (δ15N)값은 정점 간 큰 차이를 나타내지 않아, 이들이 각 서식처에서 유사한 영양위치를 점유하고 있다는 것을 나타내었다. 주둥치는 만 전체에 널리 분포하고 있어 광염성 어류의 특성을 잘 대변하는 것을 보였는데, 상대적으로 소형개체들이 하구역에서 채집되는 반면 대형 개체들이 광양만에 분포하여 크기에 따른 서식처 분리를 나타내었다. 결론적으로 본 연구에서 나타난 주둥치의 δ13C 값의 서식처 간 차이와 δ15N 값의 일관성은 섬진강 하구에서 유어기에 주로 동물플랑크톤을 섭이하는 반면, 광양만에서 성어기에 저서무척추동물을 섭이하는 육식성 섭식 특성과 함께 이동 중 서식환경에 따른 먹이자원의 이용에서의 변이를 잘 나타내어 주었다. 본 연구결과는 또한 광염성 어류의 서식처 특성과 먹이 이용 패턴을 파악하기 위한 연구에 안정동위원소 분석기법의 유용성을 잘 보여주었다.

연안생태계에서 아미노산의 질소 안정동위원소 비를 이용한 배경질소 안정동위원소 비 파악

최보형(Bohyung Choi),최현태(Hyuntae Choi),신경훈(Kyung-Hoon Shin) 전남대학교 수산과학연구소 2020 수산과학연구소논문집 Vol.28 No.2

In order to estimate trophic position and to determine nitrogen isotopic baseline in the coastal ecosystems, present study analyzed nitrogen isotope ratio of individual amino acid of oyster which sampled in two different estuaries. Trophic position (TP) of oysters estimated by nitrogen isotope ratio of bulk tissue showed spatial and temporal variation (1.4 to 2.2), while trophic position of oyster estimated by nitrogen isotope ratio of amino acids was nearly varied between sampling sites and seasons (1.8 to 2.2). In addition, present study showed depleted nitrogen isotope ratio of phenylalanine compare to that of bulk tissue in the sampled oysters (approximately 3.0‰). The light nitrogen isotope ratio of phenylalanine is expected to be an indicator of nitrogen isotopic baseline with elimination of trophic enrichment in the consumers. Moreover, we estimated nitrogen isotopic baseline using both bulk and compound specific nitrogen isotope ratio of oyster and found similar values among sampling sites and seasons. The suggested estimation will be alternatively applied to the trophic ecology.

조간대 퇴적 환경에 따른 저서미세조류 색소와 총 아데노신 3인산(ATP: Adenosine-5' triphosphate) 비교 연구

하선용,최보형,민준오,전수아,신경훈 한국해양과학기술원 2013 Ocean and Polar Research Vol.35 No.1

Biomass and community composition of microphytobentos in tidal flats were studied by HPLC analysis and also investigated to examine the relationship between microphytobenthic pigments and Adenosine-5' triphosphate (ATP) as an index of total microbial biomass in intertidal environments (muddy and sandy sediment) of Gyeonggi Bay, west coast of Korea. Microphytobenthic pigments and ATP concentration in muddy sediment were the highest at the surface while the biomass of microphytobenthos in sandy sediment was the highest at the sub-surface (0.75 cm sediment depth). The detected pigments of microphytobenthos were chlorophyll a, b (euglenophytes), c3, peridinin (dinoflagellates), fucoxanthin (diatom or chrysophytes), diadinoxanthin, alloxanthin (cryptophytes), diatoxanthin, zeaxanthin (cyanobacteria), β-carotein, and pheophytin a (the degraded product of chlorophyll a). Among the pigments which were detected, the concentration of fucoxanthin was the highest, indicating that diatoms dominated in the microphytobenthic community of the tidal flats. There was little significant correlation between OC (Organic Carbon) and ATP in both sediments. However, a positive correlation between chlorophyll a concentration and ATP concentration was found in sandy sediment, suggesting that microbial biomass could be affected by labile OC derived from microphytobenthos. These results provide information that may help us understand the relationship between microphytobenthos and microbial biomass in different intertidal sediment environments.

영흥도 조간대 갯벌 저서미세조류의 생태적 중요성; 안정동위원소 분석 활용

강수진,최보형,한용진,신경훈 한국수생태학회(구 한국하천호수학회) 2016 생태와 환경 Vol.49 No.2

수생태계 먹이망 해석과 아미노산질소안정동위원소를 이용한 오염물질 축적계수 도출

원은지,최보형,홍성진,이종현,신경훈 환경독성보건학회 2019 한국독성학회 심포지움 및 학술발표회 Vol.2019 No.10

오존(O₃) 노출에 의한 조각깔따구(Glyptotendipes tokunagai)의 체색 변화 및 heat shock protein 70 발현 변화

김원석,최보형,김문경,채선하,곽인실,Kim, Won-Seok,Choi, Bohyung,Kim, Moon-Kyung,Chae, Seon Ha,Kwak, Ihn-Sil 한국하천호수학회 2020 생태와 환경 Vol.53 No.4

오존은 수돗물 정수장에서 이용되는 소독 물질로 미세오염 물질들을 비롯해서 박테리아나 병원성 미생물체를 효과적으로 제거하는 것으로 많은 연구가 보고되어 있다. 본 연구에서는 실내 사육 중인 붉은 체색을 지닌 Glyptotendipes tokunagai를 대상으로 서로 다른 농도의 오존 노출에 따른 영향을 파악하기 위해 치사율, 체색 변화와 heat shock protein 70 (HSP70) 유전자 발현을 측정하였다. 오존에 노출된 G. tokunagai에서 농도-시간 의존적으로 치사율 증가가 관찰되었다. 또한 체색 변화는 오존 농도에 따라 붉은색의 체색이 체절마다 엷어지며 탈색되고 경직되는 현상이 보였다. HSP70 유전자 발현은 저농도인 0.2~0.5 ppm에서 노출 10분과 20분에 유의한 수준으로 높게 나타났으나(P<0.05), 30분 노출 후에는 발현량이 감소하는 경향을 보였다. 생리적으로 저산소층에 대해 적응능력이 뛰어난 깔따구 경우에도 오존은 매우 강력한 치사 효과를 유발하여 30분 노출 후 경직과 헤모글로빈 파괴로 인한 탈색이 유발되는 것을 보여주었다. 따라서 본 결과는 수돗물 정수장에서 병원성 미생물을 제거하는 데 사용되는 오존이 수생물에 주는 영향성을 파악하는 기초자료로서 활용될 수 있을 것이다. Ozone (O₃) is a general disinfectant to remove micro-pollutants in water treatment system. Previous studies have reported effect of ozone to bacteria and pathogens removal, but its effect to the relatively large organisms has little known. In this study, we investigated potential effects of ozone toxicity to the non-bite midge larvae (Glyptotendipes tokunagai) with accumulate mortality, coloration change and expression of heat shock protein 70 (HSP70). The accumulate mortality rate of G. tokunagai increased in a dose-time dependent manner and the highest mortality rate was observed to 75% at 30 minute of exposure duration with 2.0 ppm of ozone concentration. Exposure to ozone was a factor increasing body color of the larvae. The tendency of HSP70 mRNA expression showed up-regulation in ozone exposure at 20 minute. After that time, the expression of HSP70 in exposed group decreased to a similar level of control group. Our results clearly showed that ozone toxicity affects physical and molecular activity of G. tokunagai, implying the potential hazardous of ozone in the aquatic ecosystem including macroinvertebrates.

금강 하구 생태계에서 아미노산의 질소 안정동위원소비를 이용한 섭식생물의 영양단계 파악

최현태,최보형,신경훈 한국하천호수학회 2017 생태와 환경 Vol.50 No.4

Compound specific isotope analysis of amino acids (CSIA-AAs) is being highlighted as an alternative approach for overcoming some restrictions in application of stable isotope analysis of bulk tissue (SIA) for trophic position (TP) estimation. However, this approach has rarely been applied in Korea. The present study determines TP of two Polychaeta (Nephtyidae and Glyceridae) and two fish species (Platycephalus indicus and Lophius litulon) collected from the Geum River estuary using nitrogen isotope ratio of amino acid and compared with the TP values estimated by SIA. The Polychaeta species, sampled in two sites, showed similar TP between SIA (2.7 and 3.1) and CSIA-AAs (2.6 and 3.1). However, for both fish species, TP values displayed a large difference between SIA (3.1 and 2.3) and CSIA-AAs (3.8 and 3.7). In this study TP values estimated by CSIA-AAs showed more similar to the previously reported gut content analysis of both fishes compared with the results of SIA. Current study suggests the applicability of nitrogen isotope ratio of amino acid to understand coastal ecosystem structure and trophic ecology.

울산만 먹이망을 통한 유해독성물질의 생물농축확대 연구: 아미노산의 질소 안정동위원소 분석의 적용

안윤영,홍성진,최보형,신경훈 환경독성보건학회 2019 한국독성학회 심포지움 및 학술발표회 Vol.2019 No.10

낙동강 수생태계 먹이망 구조 분석: 안정동위원소 비 기반의 정량적 생태정보를 이용한 영양단계 시공간 분포 경향 파악

오혜지,jinmeiyan,최보형,신경훈,나긍환,김현우,장민호,이경락,장광현 한국하천호수학회 2019 생태와 환경 Vol.52 No.1

Recently, quantitative analyses of food web structure based on carbon and nitrogen stable isotopes are widely applied to environmental assessments as well as ecological researches of various ecosystems, particularly rivers and streams. In the present study, we analyzed carbon and nitrogen stable isotope ratios of POM (both planktonic and attached forms), zooplankton, benthic macroinvertebrates and fish collected from 6 sites located at Nakdong River. Samples were collected from upstream areas of 5 weirs (Sangju, Gangjeong-Goryeong, Dalseong, Hapcheon-Changnyeong, and Changnyeong-Haman Weirs) and one downstream area of Hapcheon-Changnyeong Weir in dry season (June) and after rainy season (September). We suggested ranges of their carbon and nitrogen stable isotope ratios and calculated their trophic levels in the food web to compare their temporal and spatial variations. Trophic levels of organisms were relatively higher in Sangju Weir located at upper part of Nakdong River, and decreased thereafter. However, the trophic levels were recovered at the Changnyeong-Haman Weir, the lowest weir in the river. The trophic level calculated by nitrogen stable isotope ratios showed more reliable ranges when they were calculated based on zooplankton than POM used as baseline. The suggested quantitative ecological information of the majority of biological communities in Nakdong River would be helpful to understand the response of river food web to environmental disturbances and can be applied to various further researches regarding the quantitative approaches for the understanding food web structure and function of river ecosystems as well as restoration.