• Korean Journal of Ecology and Environment
• /
• v.45 no.1
• /
• pp.1-10
• /
• 2012

The Jinwi stream, which is located in the Gyeonggi Province, shows a large variation in water quality from the upper stream to downstream. Therefore the Jinwi stream is suitable for assessing changes to the benthic macroinvertebrate community structure according to saprobity. This study was conducted to find out the applicability of biotic indices for water quality pollution through an analysis of the correlation between water quality and benthic macroinvertebrate indices for the Jinwi stream. Along with the pollution of water, the species composition of Ephemeroptera decreased, while that of Annelida increased. The ecological score for the benthic macroinvertebrate community (ESB) showed more significant correlations than any other biotic index (H', DI, R1, J, EPT and KSI) with the water quality items.

• ALGAE
• /
• v.35 no.4
• /
• pp.361-373
• /
• 2020

The community dynamics of benthic diatoms in the hypersaline environment are investigated to advance our understanding how salinity impacts marine life. Diatoms were sampled in the two salterns encompassing salt Ponds, ditches, and seawater reservoirs (n = 11), along the salinity gradient (max = 324 psu), and nearby tidal flats (n = 2). The floral assemblages and distributions across sites and stations showed great variations, with a total of 169 identified taxa. First, not surprisingly, higher diversity of benthic diatoms was found at natural tidal flats than salterns. The saltern diatoms generally showed salinity dependent distributions with distinct spatial changes in species composition and dominant taxa. Biota-environment and principal component analysis confirmed that salinity, mud content, and total nitrogen were key factors influencing the overall benthic community structure. Some dominant species, e.g., Nitzschia scalpelliformis and Achnanthes sp. 1, showed salinity tolerance / preference. The number of diatom species at salinity of >100 psu reduced over half and no diatoms were found at maximum salinity of 324 psu. The highest salinity for the observed live diatoms was 205 psu, however, a simple regression indicated a theoretical salinity threshold of ~300 psu on the survival. Finally, the indicator species were identified along the salinity gradient in salterns as well as natural tidal flats. Overall, high species numbers, varying taxa, and euryhaline distributions of saltern diatoms collectively reflected a dynamic saltern ecosystem. The present study would provide backgrounds for biodiversity monitoring of ecologically important microalgal producers in some unique hypersaline environment, and elsewhere.

• Journal of Korean Society on Water Environment
• /
• v.27 no.6
• /
• pp.855-861
• /
• 2011

Short-term effects of current velocity and turbid water on the benthic diatom community and water quality were examined in artificial channel ($20{\times}200{\times}10cm$) with two different experiments. The first and second experiments were consisted of different current velocities such as 1 L/min., and 1, 3, and 6 L/min., respectively. The concentration of turbid water is prepared with loess and fixed at 10 and 20 times of the turbidity of control inflow (10 NTU, LTW), respectively. At experiment 1 (EXP-1), introduction of turbid water increased dissolved oxygen, electric conductivity, pH and turbidity, but there were no differences between low- (100 NTU, MTW) and high-turbid water (200 NTU, HTW). However, experiment 2 (EXP-2) did not change any environmental parameters except dissolved total and inorganic nitrogen like EXP-1. MTW in EXP-1 strongly stimulated the growth of benthic diatom, while both MTW (150 NTU) and HTW (300 NTU) in EXP-2 did not increase or decrease the diatom abundance. Over the study, the dominant species was four, Aulacoseira ambigua, Cyclotella stelligera, Aulacoseira granulata and Achnanthes minutissima. In EXP-1, two highest species in abundance, A. ambigua and A. granulata were highly grown in MTW, while Achnanthes minutissima high in HTW adversely. These results indicate that the introduction of turbid water can play an important role in the shift of water quality and benthic diatom community in stream ecosystem, especially inflow of soil water in low current velocity.

• The Korean Journal of Ecology
• /
• v.8 no.1
• /
• pp.7-14
• /
• 1985

Biomass, carbon, nitrogen and phosphorus standing crops of bethic community were estimated at the trophic levels in the intertidal zone of Kum river estuary. Annual mean biomass of zoobenthos was 130.5g/$m^2$, body fraction 26.7g/$m^2$ and shell fraction 103.8 g/$m^3$. Biomass estimated as ash-free dry weight was total 28.9g/$m^2$, body fraction 20.2g/$m^2$ and shell fraction 8.7g/$m^2$ Carbon standing crops of zoobenthos were 15.9gC/$m^2$, in which organic carbon content was 7.0gC/$m^2$ and carbonate carbon was 8.9gC/$m^2$. Production efficiency by carbon standing crops from sediment to herbivores and carnivores and 10.6% and 16.0% in phosphorus, respectively. Annual primary production of benthic algae was crudely estimated to 329g.dw/$m^2$/yr by using the biomass and turn-over rate of benthic algae.

• The Korean Journal of Malacology
• /
• v.7 no.1
• /
• pp.58-65
• /
• 1991

A study on the distribution and community structure of the benthic molluscan shells of the southern coastral area in Cheju Island was carried out from August 1990 to July 1991. The benthic molluscan shells collected and identified from 8 stations were composed of 3 classes, 7 orders, 22 families and 59 species. The number of appearance species from station 1 to station 8 were 22, 35, 32, 26, 28, 24, 32 and 31 species respectively. the first dominant species of the upper intertidal zone of the 8 stations were Nodilittorina exigua, those of the middle zones were Monodonta neritoides from st.1 to St.5, but the second dominant species were not uniftom at ach station.

• Journal of Navigation and Port Research
• /
• v.30 no.4
• /
• pp.309-314
• /
• 2006

Community structure and biodiversity of benthic marine algae were studied in the rocky shore of Phohang New Port, Yeoungil Bay. A total of 79 species of marine algae including 8 Chlorophyta, 23 Phaeophyta and 48 Rhodophyta are listed. The dominant algal species were Corallina pilulifera in all seasons, and Sargassum homeri in winter. Lomentaria catenata, Lomentaria hakodatensis, Grateloupia laceolata, Sargassum thunbergii, Chondria crassicaulis, Ulva pertusa, and Hypnea charoides were subdominant at different seasons. The algal biomass per unit area of the benthic algal community in Pohang New Port under construction was 14506 - 398.93 g dry wt m-2, which means that its annually averaged value is 273.45 g dry wt m-2 . The seasonal change in algal biomass showed highs in winter and spring, and lows in summer and autumn. The algal species diversity (H') based on algal biomass was 2.07 annually in average, with 2.42 in winter, 2.65 in spring, 1.79 in summer and 1.43 in autumn. It was high in winter and spring seasons and low in summer and autumn seasons. It is caused by that spring and winter are the profitable growth time for algae and species components in this study were dominated by the annual or seasonal rather than perennial plants.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
• /
• v.8 no.4
• /
• pp.420-425
• /
• 2003

Species composition, community structure and biodiversity of marine benthic community were studied in the intertidal zone of Seoam, Busan. A total of 75 species of benthic marine plants including 4 Cyanophyta, 6 Chlorophyta, 17 Phaeophyta, 47 Rhodophyta and 1 Magnoliophyta are listed. The dominant marine plants were melobesioidean algae, Chondracanthus tenellus, Sargasium thunbergii, Corallina spp., and Phyllospadix japonica and Ulva pertusa was added in summer. Chthamalus challengeri and Mytilus edulis were dominant zoobenthic species in the upper and middle intertidal zone. The algal species diversity index based on coverage was 1.81; 2.25 from frequency; 2.19 from average of total frequency and coverage, and 1.80 from importance value. The algal diversity indices estimated from different sources were quite different. This means that the index value changes depending on the sources used to calculate the species diversity index, indicating how important it is to select the based data and that it is necessary to standardize the methodology when studying later the algal diversity index. On the other hand, the number of species identified in this study has been found to be reduced by 65% at highest, compared with the result of the investigation that was conducted in the coast of Busan.

• The Korean Journal of Malacology
• /
• v.5 no.1
• /
• pp.10-28
• /
• 1989

A study on the distribution and community structure of benthic macroinvertebrates on the intertidal zone of Cheju Island was carried out from June 1988 to May 1989. The macroinvertebrates collected and identified were composed of 7 phyla, 14 classes, 29 orders, 71 families and 135 species in this study. The dominant species of the upper tidal zone were Nodilittorina granularis and Heminerita japonica, those of the middle tidal zone were Monodonta neritoides and Lunella coronata coreensis, However, Monodonta neritoides and Chlorostoma arhyrostoma lischkei were dominant in the lower tidal zone. Community dominant indices were significantly high in the upper tidal zone. Macuoinvertebrates species which have the ability of resistance to the physical factors such as, strong waves and exposure to the hot sunlight were mainly distributed on the intertidal zone of Cheju Island. The difference in the number of species among seasons was not significant, but thao among zones was quite apparent and the lower the zone, the more abundant.

• Ocean and Polar Research
• /
• v.23 no.3
• /
• pp.255-264
• /
• 2001

Development process of benthic community on experimental substrata attached on a newly installed artificial reef complex in Jeju Island was observed for 27 months from 1992 to 1994. Among 34 species of algae and 64 species of zoobenthos obtained from the study, Ecklonia cava dominated with a maximum biomass of about $10kg/m^2$. It was able to smother the other animals, however it provided a new substrate for the new settlers. Opportunistic bryzoans such as Likenopora radiata and Dexiospira spirillum occurred during the early stage were substituted by poriferans, banacles and other bryzoans. Young barnacles were smothered by bryozoans, on the contrary, bryozoans were bulldozed by adult barnacles. No apparent differences have been observed between vertically and horizontally installed substrates in terms of species composition and biomass during the early stage of succession. Thereafter owing to the rapid growth of E. cava, the horizontal substrata carried on a higher biomass while the vertical showed a higher coverage. The benthic process on the experimental substrata can be classified into three stages: initial stage, build up stage and regulatory stage. Important mechanisms involved were canopying of E. cava, suffocation by bryozoans and poriferans, and bulldozing of adult barnacles.

• Journal of environmental and Sanitary engineering
• /
• v.16 no.3
• /
• pp.62-71
• /
• 2001

The present study was performed to examine the community structure of benthic macroinvertebrates in the provincial park of Mt. Daedun and its nearby region. Sampling was conducted two times in May.June and October.November, 2000. Main two areas are Mt. Anpyong (470.0m) and Mt. Daedun (877.0m) area. Total taxa of benthic macroinvertebrates were 111 species, 47 families, 15 orders, 6 classes in 4 phyla. Aquatic insects were composed of 29 species in ephemeroptera, 10 species in odonata, 7 species in plecoptera, 2 species in hemiptera, 2 species in megaloptera, 23 species trichuptera, 6 species in coleoptera and 17 species in diptera. Other non-insects were composed of 1 species in platyhelminthes, 8 species in gastropoda, 2 species in oligochaeta, 3 species in hirudinea and 1 species in crustacea. Ephemeroptera, trichoptera and plecoptera as indicators in clean water were very abundantly. Occurrence species at each surrey area was 77 species at Mt. Anpyong area and 89 species at Mt. Daedun area, respectively. Mean values of species diversity indices were 3.04 and 2.69, respectively. According to the saprobic system based on the species diversity indices of benthic macroinvertebrates, Mt. Anpyong region are determined as polysaprobic area or ${\beta}-mesosaprobic$ area and Mt. Daedun region are determined as polysaprobic area, $\beta-mesosaprobic$ area or ${\alpha}-mesosaprobic$ area.