• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.38 no.1
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• pp.1-10
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• 2002

Biomass distribution of zooplankton showed its lowest level in June in the Cheju Strait, and the highest one was noticed in November when the secondary productivity is considered high. The highest biomass of zooplankton appeared in the sea areas of Sta. 14 and 11 respectively with relation to oceanographic conditions and wet weight of biomass. The positions were the center part of the Cheju Strait, while the sea area of the South Sea of Korea and the northern coast of Cheju Island showed relatively low biomass distribution. The characteristic of the sea area where biomass was densely distributed was it was in patch shape. Meanwhile, biomass distribution was higher in the northern sea area of Cheju Island than In the coastal sea of the South Sea of Korea. It shows formation of hairtail fishing grounds is closely related to biomass distribution in the Cheju Strait. In addition, high biomass is displayed in the center part of the saddle shaped ocean, a boundary of the heterogeneous water mass as a feature of fall oceanographic condition. Good fishing grounds of a hairtail In the Cheju Strait were formed outside of the sea area that showed patch-shaped high biomass distribution.

• Journal of Plant Biology
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• v.38 no.4
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• pp.389-398
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• 1995

The species composition and biomass of intertidal benthic algae at 12 widely dispersed stations representative of mid-western coast of Korea were studied. A total of 151 species of marine algae including 19 Cyanophyta, 20 Chlorophyta, 32 Phaeophyta and 80 Rhodophyta is listed. Three species were found at all 12 stations: Sargassum thunbergii, Stylonema alsidii and Gracilaria verrucosa. Biomass per unit area exhibited a wide range of variation, ranging from a low of 41 g dry $wt{\cdot}m^{-2}$ at both Paeksajang and Taechon to a high of 549 g dry $wt{\cdot}m^{-2}$ at Uihangri, the northernmost station of the study area. The latter value is higher than those reported from any other stations in western coast of Korea. Biomass was composed largely of Phaeophyta at nearly every station. Sargassum thunbergii was dominant over the study area. The distribution of Corallina spp., however, is disjunct, since those occur as dominant species in biomass at the northern stations and to a lesser extent at the southern stations, but are nearly absent from the middle part of the study area.

• Korean Journal of Ecology and Environment
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• v.39 no.3 s.117
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• pp.378-389
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• 2006

Seasonal changes of biomass and cell size of bacteria and protozoa, and factors affecting their distribution in Lake Paldang and Kyungan Stream were analyzed from April to December, 2005. Bacterial abundance at Paldang Dam and Kyungan Stream was similar, but it did not much increase during hot summer period. Protozoan carbon biomass was much greater at Kyungan Stream compared to Paldang Dam. HNAN generally accounted for the majority of total protozoan biomass, but ciliates made up the highest proportion in April and November at Paldang Dam and June at both sites. PNAN showed low biomass at both sites, but it was high during spring and fall season. Small-sized HNAN ($3{\sim}7\;{\mu}m$) numerically predominated the protozoan community at both sites. Average cell size of HNAN was bigger at Kyungan Stream where nutrients concentration was much higher than Paldang Dam. Average cell size of ciliates varied seasonally; it was relatively small during the summer. HNAN biomass significantly correlated with Chl-a concentration and ciliates biomass at Paldang Dam, indicating that HNAN increase might link to the ciliates increase. At Kyungan Stream, HNAN biomass showed a significant relationship with PNAN biomass, and Chl-a concentration was closely related with both of HNAN and PNAN biomass. Ciliate biomass showed significant relationship with nutrient (TN, TP) and particulate matter (SS) only at Kyungan Stream. At both sites, protozoan biomass was significantly correlated with bacterial biomass, and ciliates were additionally related flagellates. High biomass of microbial components and the close relationships among them suggest that the energy transfer through the microbial loop may important in the plankton food web of Lake Paldang ecosystem.

• Korean Journal of Environment and Ecology
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• v.30 no.6
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• pp.1022-1031
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• 2016

Relationships of standing biomass with biodiversity and structural diversity were examined in the Quercus mongolica-dominated forest in Mt. Jeombong, Gangwon-do. We examined the standing biomass of the Q. mongolia community ($311.1ton{\cdot}ha^{-1}$) from 2004 to 2013, and the observed major species were Q. mongoilca, Carpinus cordata, Tilia amurensis whose standing biomasses were $206.3ton{\cdot}ha^{-1}$ (66.3%), $36.9ton{\cdot}ha^{-1}$ (11.9%), and $30.6ton{\cdot}ha^{-1}$ (9.8%), respectively. Although the number of Q. mongolica individuals was very small compared with total density, the reason that Q. mongolica showed the most biomass than other species is due to greater average diameter at breast height (DBH) and the higher number of $DBH{\geq}50cm$ individuals. We calculated the range of Shannon index (H') and Shannon evenness (J') in the Q. mongolica community, and they were gradually increased in time, showing 2.015~2.166, 0.673~0.736, respectively. Their H' and J' showed positive linear relationships with their standing biomass. This indicates that the spatial distribution of the standing biomass in Q. mongoilca community becomes more homogeneous with time and this homogenization appears in various species in the community. In addition, we estimated biomass-species index (BS) and abundance-biomass-speciesdiversity (ABS) and they also showed gradual increase in time, ranging from 3.746 to 3.811 and from 4.781 to 5.028, respectively. Their indices showed positive linear relationships with the standing biomass. This can be explained from the observations of variations in standing biomass with tree diameters as the differences in the average standing biomass in the community have reduced gradually in time. Moreover, it is expected that increase in the structure diversity of the Q. mongoilca community enhances the efficiency in carbon sequestration and productivity, so the community can be developed to a more sustainable ecosystem with more abundant resources. Thus, applications of uneven-aged plantations with considerations of local ecological properties can be a very efficient reforestation method to ensure stable support of biodiversity and productivity.

• Journal of Korean Society of Forest Science
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• v.110 no.4
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• pp.554-568
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• 2021

Forests are the largest carbon (C) sinks in terrestrial ecosystems. Recently, as enhancing forest C sequestration capacity has been proposed as a basic direction of the Republic of Korea's "2050 Carbon Neutral Strategy," accurate estimation of forest C sequestration has been emphasized. According to the Intergovernmental Panel on Climate Change guidelines, sequestration quantity is calculated from changes in C stocks in forest C pools, such as biomass, deadwood, litter and soil layer, and harvested wood products. However, in Korea, only the overstory biomass increase is now considered the amount of sequestration quantity, so there can be a significant difference from the actual forest C sequestration. In this study, we quantified forest C exchange through C flux measurement using an eddy covariance system and an automated soil chamber system in a 57-year-old Korean pine plantation located in Mt. Taehwa, Gwangju-si, Gyeonggi-do. Then, the net amount of C sequestration was compared with the amount of the overstory biomass increase. We estimated the annual C stock change in the remaining C pools by comparing the net sequestration amount from the C flux measurement with the overstory biomass increase and C stock change in the litter layer. Therefore, the net C sequestration of the Korean pine plantation estimated from the flux measurement was 5.96 MgC ha^-1, which was about 2.2 times greater than 2.77 MgC ha^-1 of the overstory biomass increase. The annual C stock increase in the litter layer was estimated to be 0.75 MgC ha^-1, resulting in a total annual C stock increase of 2.45 MgC ha^-1 in the remaining C pools. Our results indicate that the domestic forest is a larger C sink than the current methods, implying that more accurate calculations of the C sequestration capacity are necessary to quantify C stock changes in C pools along with the C flux measurement.

• Journal of Wetlands Research
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• v.20 no.2
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• pp.116-123
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• 2018

The objective of this study was to examine effects of stand age on soil $CO_2$ efflux in plantation Pinus koraiensis, and to elucidate what extent plant (fine) root and soil microbial biomass contribute to the whole soil $CO_2$ efflux. In three age classes (20-yr-old. 40-yr-old, 70-yr-old) of plantation Pinus koraiensis, in-situ soil respiration, plant fine root biomass and soil microbial biomass were measured from April to November in 2004. Regardless of stand age, soil temperature and soil $CO_2$ efflux increased until July then slowly decreased. Soil respiration was higher in 70-yr-old stand than in 20- and 40-yr stands. Fine root biomass and soil microbial biomass was also higher in 70-yr-old stand. Root exclusion decreased soil respiration in 40-yr stand, but not in 70-yr stand. Soil microbial biomass was higher in 70-yr stand, but there was no monthly variation between July and November. The results suggest that soil respiration may increase as plant stand ages and microbial contribution could play more roles in older stands.

• Journal of the Korean Society of Marine Environment & Safety
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• v.25 no.2
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• pp.212-219
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• 2019

This study was conducted to investigate marine algal community characteristics and the status of barren ground in the summer at study sites on Jeju Island, Korea. Sampling was carried out from July to September 2017 using a qualitative and quantitative survey (including coverage of non-geniculated coralline algae and density of grazer) by scuba diving. A total of 121 species were identified, including 11 (9.1 %) green algae, 24 (19.8 %) brown algae, and 86 (71.1 %) red algae. Hyeongjeseom had the greatest diversity, with 60 species, and Harye the least, with 18 species. The mean biomass at the study sites was $1,503.0g{\cdot}m^{-2}$, while the mean for the neighboring islets ($3,268.7g{\cdot}m^{-2}$) was higher than that of the main island ($914.7g{\cdot}m^{-2}$). Also, dominant species was identified: Sargassum macrocarpum at the neighboring islets, and Ecklonia cava at the main island, with differences showing not only in biomass but also species composition. In conclusion, the marine algal community status in summer at the study sites was evaluated based on the algal community characteristics (species composition, biomass, biomass ratio of kelp species), coverage of non-geniculated coralline algae, and density of grazer. As a result, both Hyeongjeseom and Marado require preservation and management to maintain their excellent marine algal communities, and other sites on the main island require the creation and/or restoration of marine algal communities. In addition, as the generation of barren ground accelerates, it is urgent not only to grasp existing monitoring research but also to identify the status of the marine algal community where it is not known at present.

• 한국해양학회지
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• v.26 no.3
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• pp.291-294
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• 1991

MAPP a computer program provides an estimate of the annual production of macroalgae. The calculation of the annual production is based on the Photosynthesis-Irradiance relationship under different temperature conditions and annual changes of algal biomass. The production in a given time was obtained from the multiplication of biomass by the production rate measured by in situ experiments. The annual production, $P_{yr}$, is calculated from $P_{yr}{\;}={\;}{\int}B_t{\cdot}P_r{\;}dt$, where, $P_t$ = f(T,L)and T, L = f(t). The program is written in Pascal language to facilitate the usage with personal computers. The data of the photosynthetic rates and biomass of Sargassum confusum measured at Ohori, on the east coast of Korea, was used for an example.

• Proceedings of the Korean Aquaculture Society Conference
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• 2003.10a
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• pp.97-97
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• 2003

유용 수산생물인 전복, 소라, 성게 등 무척추동물의 종묘생산에 있어 부착 규조류는 수서 생태계의 일차 생산자로서 유생의 변태와 변태 후의 초기 먹이생물로 활용되고 있으며 최근에는 단일 부착규조류의 실내 배양을 통해 유용 수산생물 종묘의 대량 생산을 유도하고 있다. 부착규조류의 생물량 및 종 조성에 따라 이들 조식동물의 성장과 먹이 효율성에 커다란 영향을 끼친다. 이 연구는 종묘생산의 환경 조건과 동일한 현장에서 유수식 수조에 투명 플라스틱 부착파판(30$\times$40cm)을 설치하여 1997년 10월부터 1999년 4월까지 실내수조에 설치한 부착파판을 10일 간격으로 회수하여 부착된 규조류의 생물량과 환경적 특성을 조사하였다. 실험기간 동안 자연광을 55~75% 차단한 상태에서 실험을 진행하였고 수온과 염분은 각각 14.1$^{\circ}C$~28.6$^{\circ}C$와 32.5$\textperthousand$~35.3$\textperthousand$의 범위를 보였다. 실험기간 동안 부착규조류의 총 출현종수는 27종(17속 25종 2미동정종)으로 중심규조류(centric diatom)가 4종 그리고 우상규조류(pennate diatom)가 23종이었다. 현존량의 30% 이상을 점유하는 부착 규조류들은 Bacillaria paxillifera, Cocconeis scutellum, Diatoma hyalina, Navicula mollis, Nitzschia sp., Synedra tabulta 등 6종이 우점하였다. 부착규조류의 현존량은 2.5$\times$$10^3$~ 5.0$\times$$10^{5}$ cells $cm^{-2}$ 의 분포 범위로 1999년 4월에 가장 높고 1997년 10월에 가장 낮았다. Chlorophyll $\alpha$량 ($\mu\textrm{g}$ chl $\alpha$ $cm^{-2}$)은 0.02 ~ 1.72 $\mu\textrm{g}$ chi $\alpha$ $cm^{-2}$의 범위로써 부착규조류의 현존량과 유사한 분포 특성을 보였다. 유수식 실내수조에 부착된 부착규조류의 부착 형태, 우점종과 현존량은 배양 시기에 따라 종간 특이성을 보였다.다.

• Korean Journal of Environmental Biology
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• v.27 no.1
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• pp.114-123
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• 2009

The species composition and biomass of coralline algae around three (Uljin, Wolseong and Gori) nuclear power plants on the east coast of Korea were investigated seasonally from February 1997 to October 2006. As a result, 13 species of coralline algae were found during the past ten years. Among them, Corallina pilulifera, C. officinalis, Amphiroa zonata and Pneophyllum zostericolum were common species that occurred more than 50% in frequency during the study period. Species number of coralline algae were between 10$\sim$12 species at the breakwaters near the outfalls of power plants and 8$\sim$12 species at the control area, and differences in species composition were not observed among study sites. Seasonal fluctuations of mean biomass were 0$\sim$2,530 g dry wt m$^{-2}$ and dominant species in biomass was Corallina pilulifera at all the study sites. The breakwaters of power plants generally had a greater coralline algal biomass than the control area. Biomass proportions of coralline algae at the breakwaters of power plants were also higher than those at the control area. At the Uljin sites, particularly, biomass of coralline algae showed greatest in summer and biomass proportion showed highest during the summer season. Differences in the spatio-temporal patterns of coralline algae around three nuclear power plants on the east coast of Korea were presumably due to the regional temperature variations.