• Korean Journal of Soil Science and Fertilizer
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• v.45 no.6
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• pp.1136-1142
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• 2012

The roles of paddy fields are re-evaluated as an artificial wetland. Although 44% of total aquatic invertebrates in South Korea are observed in a rice paddy, information of their distribution and characteristics of habitat use is limited yet. This study was carried out to provide information and characterizing distribution of community of aquatic invertebrates using a rice paddy through the South Korea. Aquatic invertebrates were collected at 284 sites of a rice paddy in South Korea from June to August, 2005, 2006 and 2007. We grouped sampling sites according to its species and population of aquatic invertebrates using a non-metric multidimensional scaling (NMDS). Total 21 orders 60 families 114 species were collected from a rice paddy. Coleoptera (25%), Heteroptera (17%), Diptera (17%) and Odonata (12%) were observed. Aquatic invertebrates were classified into three groups (Group 1: Gangwon, Gyeonggi and Chungbuk; Group 2: Chungnam, Jeonbuk, Jeonnam and Jeju; Group 3: Gyeongbuk and Kyeongnam). In Group 1, Muljarus japonicas distributed mainly Gangwondo and Chungbuk. In Group 2, Sigara nigroventralis and S. substriata were mainly observed. In Group 3, higher density of Daphnia sp. and Chironomidae gen. spp. was found in the southern part of Korea.

• Fisheries and Aquatic Sciences
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• v.22 no.6
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• pp.13.1-13.9
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• 2019

Background: Marine invertebrates are well known as pivotal bioresources with bioactive substances such as anti-inflammatory sterols, antitumor terpenes, and antimicrobial peptides. However, there are few scientific reports on chemical compositions and bioactivities of marine invertebrates from the East Sea of South Korea. Methods: In this study, chemical compositions and biological activities were evaluated on both 70% EtOH and hot water extracts of 5 species of marine invertebrates (Crossaster papposus japonicus, Actinostola carlgreni, Stomphia coccinea, Actinostola sp., and Heliometra glacialis) collected from the East Sea of South Korea. The antioxidant activities were measured by ABTS radical scavenging assay. The cytotoxicity and anti-inflammatory activity were evaluated using MTT and Griess reagents. Moreover, the antibacterial effect was evaluated using paper disc assay and minimum inhibitory concentration (MIC) assay. Results: In the results of antioxidant activities, 70% EtOH extract of A. carlgreni showed the highest activity ($IC_{50}\;0.19{\pm}0.03mg/ml$) compared to other extracts. Moreover, 70% EtOH extract of A. carlgreni could significantly suppress the nitric oxide (NO) production in lipopolysaccharide-induced RAW 264.7. All extracts treated under $400{\mu}g/ml$ have no cytotoxic effects on RAW 264.7 macrophages. In the antibacterial test, both 70% EtOH extracts of C. papposus japonicus and H. glacialis showed a significant antibacterial effect on Staphylococcus aureus. The MIC values were evaluated at 256 and $512{\mu}g/ml$, respectively. Conclusions: These results suggested the bioactive potentials of marine invertebrates from the East Sea of South Korea in pharmaceutical and nutraceutical applications.

• Korean Journal of Ecology and Environment
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• v.35 no.3 s.99
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• pp.172-180
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• 2002

Leaf litter breakdown rates of the Phragmites australis, Zizania latifolia and Typha angustifolia were determined at the lower Nakdong River from Nov. 1998 to Sept. 1999. The relationship between leaf litter breakdown of three and abundance of aquatic invertebrates was investigated. Aquatic invertebrates collected in the litterbags were 11 family, 11 species (mean density: $222\;ind./m^2$ , n = 792), and Chironomidae was dominant. Mean density of Chironomidae in the litterbags were different according to the aquatic plant species: Z. latifolia ($180\;ind./m^2$, n = 264) T. angustifolia ($187\;ind./m^2$, n = 264) P. australis ($95\;ind./m^2$, n = 264). The breakdown of Z. latifolia was the shortest, and that of T. angustifolia was shorter than P. australis. Overall, the breakdown rate at floating layer was faster than that of submerged layer in all of three species and differences of the breakdown rate between open bags and closed three species and differences of the breakdown rate between open bags and closed bags were not found.

• Fisheries and Aquatic Sciences
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• v.1 no.2
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• pp.232-241
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• 1998

Fatty acid compositions of 35 species of marine invertebrates (13 species of Bivalvia, 10 species of Gastropoda, 4 species of Cephalopoda, 4 species of Crustacea, 2 species of Ascidacea, 2 species of Holothuroidea) were studied using gas-liquid chromatography. Total lipids in all samples were very low, ranging from $0.24\%$ to $1.96\%$. The prominent fatty acids were 16:0, 20:5 (n-3), 22:6 (n-3), 18:0, 16:1 (n-7), 20:4 (n-6), 18:1 (n-9) and 18:1 (n-7) in the majority of marine invertebrates. Polyunsaturated fatty acid (PUFA) was the richest fatty acid group in all invertebrates, accounting for $55.3\pm6.70\%$ of total fatty acids (TFA), followed by saturated $(26.2\pm4.33\%)$ and monounsaturated fatty acid $(18.5\pm5.87\% )$. No correlation was found between total lipid content and each fatty acid group. Cephalopoda contained the highest level of n-3 PUFA $(54.6\pm5.17\%)$, while Holothuroidea and Gastropoda contained the lowest level of n-3 PUFA, accounting for $26.5\pm4.44\%$ and $28.4\pm4.04\%$, respectively. Bivalvia and Ascidacea are plankton feeders, which were rich in 20:5 (n-3) and 22:6 (n-3). Carnivorous species of Cephalopoda were prominently rich in 22:6 (n-3), ranging from $26.7\%$ to $46.1\%$ of the TFA. However, some species of Gastropoda are seaweed feeder (herbivorous), which contained high level of 20:4 (n-6) compared to plankton feeder and carnivorous species. In addition, blue and red colored sea cucumbers, and turban shells with and without apophyses belong to the same species, but they live in different habitats. These organisms were found to have different fatty acid compositions. Therefore, fatty acid compositions of these invertebrates might be affected by their different environments, particularly their diet.

• Korean Journal of Environmental Agriculture
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• v.8 no.1
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• pp.17-29
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• 1989

This study was conducted to evaluate the behavior in the water and the impact on aquatic organisms following aerial application of two insecticides in the forest, cyfluthrin and trichlorfon, to control the alder leaf beetle. As active ingredients, 25g of cyfluthrin and 536g of trichlorfon per ha were diluted seperately into 30L of tap water, and applied with a helicopter to the study areas. A model stream study was also conducted in a stream located adjacent to the study area in order to confirm the impact of insecticides on aquatic invertebrates. Cyfluthrin residues in water were $0.62{\mu}g/L$ (1st. application) and $78{\mu}g/L$ (2nd application) immediately after spraying. and decreased, to a non-detectable level after one day, while trichlorfon residue increased to $30.7{\mu}g/L$ one day after spraying and fluctuated for 22th day depending on precipitation after spraying. Cyfluthrin application rapidly increased the number of some drifting aquatic invertebrates during 24-hour period immediately after spraying, but had no effects on the other aquatic organisms such as fish and zooplankton. The largest increase in the number of drifting organisms following application of cyfluthrin was shown by Ephemeroptera, and followed by Trichoptera, Coleoptera, and Diptera. However, trichlorfon little affected the number of drifting aquatic invertebrates and zooplankton population.

• Proceedings of the Korean Aquaculture Society Conference
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• 2006.05a
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• pp.447-449
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• 2006

• Korean Journal of Environmental Agriculture
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• v.32 no.1
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• pp.17-23
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• 2013

BACKGROUND: Today, environmentally friendly farming has become an important feature of agricultural policy. It promotes or sustains farming systems which protect and enhance the environment. This study was conducted to compare benthic invertebrate communities in an organic and a conventional paddy field in South Korea. METHODS AND RESULTS: Benthic invertebrates were collected at 11 regions of a rice paddy from June to August, 2009, 2010 and 2011. These comparisons undertaken using a community assessment approaches such as the number of individuals and species and community composition. Generally, the larger number of individuals and species of benthic invertebrates was observed in an organic paddy than in a conventional paddy field. Organic paddy fields could supported the wider range of species and abundance in aquatic invertebrates comparing to conventional paddy fields. Carrying capacity to support larger numbers of invertebrates also tends to be higher in organic paddy than in conventional paddy field. Specially, organic farming regions surrounded by forests were high quality habitat for benthic invertebrates than other surrounded regions such as grassland. CONCLUSION(S): We concluded that organic farming was more advantaged to benthic invertebrates than conventional farming. In order to improve biodiversity in rice paddy field, farming regimes without agricultural chemicals are recommended. The effect of organic management on biodiversity and abundance of benthic invertebrates could be maximized across highland farmland.

• 한국생태학회:학술대회논문집
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• 1999.05a
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• pp.43-54
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• 1999

1. Hanoi city was built up on the wetland landscape of the Red River delta therefore it has a network of many lakes and rivers. 2. The aquatic biodiversity (Macrophytes, Invertebrates, Fishes, Vertebrates) of the 6 main lakes (Ho Tay, Hoan Kiem, Bay Mau, Giang Vo, Dong Da, Thanh Nhan) are rich and diverse. It represents the patterns of Red River delta one's. Many rare and endangered species are found in these lakes Particularly a giant freshwater turtle species in Hoan Kiem lake. 3. All of these lakes are more or less polluted. Their environments are seriously degrading both in water quality and aquatic biodiversity. 4. Based on socio-economical and cultural role of these lakes of Hanoi city, it is very necessary to preserve and to restore their environments and aquatic biodiversity: water Pollution control, landscape planning, making roads around the lakes and erosion control for their banks, legislation measures, rational exploitation of aquatic biodiversity, restoration the artificial wetlands with macrophytes.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.20 no.6
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• pp.591-600
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• 1987

To evaluate the detection rate and the density of Vibrio vulnificus by the sample, sampling area and date, 240 sea water samples and marine invertebrates were collected from coastal area of Korea including Pohang, Chungmu, Yeosu, Kunsan, Sihwa and Pusan from March to October, 1986. Eighty two strains oft of 1087 strains isolated from the submitted samples were identified as V. vulnificus. Forty seven of total 240 samples were positive in V. vulnificus which were constituted by 31 out of 138 sea water samples and 16 out of 102 marine invertebrates. Detection rate of V. vulnificus among the invertebrates was high in the crab, Portunus trituberculatus and the ark shell, Anadara broughtonii samples. The samples collected at Kunsan area showed the highest in detection rate of the bacterium as $67\%$ during the study period and the density of V. vulnificus was high in the sea water which was low in salinity.

• Korean Journal of Ecology and Environment
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• v.56 no.4
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• pp.414-419
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• 2023

Aquatic ecosystem is composed of various organic and inorganic matters. Its health is essential for sustaining its members such as vegetations, mammals, birds, fishes and invertebrates. Samcheonpo stream is one of candidate streams in Sacheon area of ecological restoration. For this reason, this study conducted to build up a data base for future comparison. The results shows that biodiversity of Epilithic Diatoms and Invertebrates is below average which means that human impacts such as artificial structures and activities have been negatively related to stream health. Consequently, we suggest several key factors when ecological restoration is performed in the stream.