• Korean Journal of Veterinary Research
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• v.31 no.4
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• pp.515-518
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• 1991

A field study of Lymnaea viridis, the intermediate host of Fasciola hepatica, was carried out in the eastern Chonnam area. The snail was distributed all over the place. Their major habitats were rice paddies (60.8%), followed by brooks (23.2%), irrigation canals (8.6%), and drains (5.6%). Other minor habitats included natural ponds (1.5%), lakes (0.4%), and rivers (0.1%). L. viridis was living in wet clay soil, occasionally entering water. The snails discharged egg masses when the temperature was $15{\sim}20^{\circ}C$, and the number of the snails was the highest late in October. At $9^{\circ}C$ the snails were not found on the mud: they were present deep in water or at the base of rice stubbles. These hibernation sites were discussed with the epidemiology of fascioliasis.

• Journal of Environmental Science International
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• v.12 no.3
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• pp.287-297
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• 2003

To investigate water quality and pollution states of rivers in Gwangju city, total of 30 water samples were taken from the main stream of Yeongsan river, Hwangryong river and Gwangju stream in dry and flood seasons. Physico-chemical characteristics of above streams according to pH-Eh and Piper's diagrams we, typically, assigned to natural river water. In the streams, BOD, COD, T-N and T-P indicating water quality mostly increase toward downstream. Notably, water qualities in area near connection between the Gwangju stream and the main stream of Yeongsan river are polluted over V level in rivers and lakes water quality standard. The pollutions are influenced by lift and agricultural foul waters from Gwangju City and farming areas around upstream branches of the Yeongsan river, reasonably. Besides, heavy metals are below the standard in those streams. So, it is considered that the streams are polluted by not industrial but life/agricultural foul waters.

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.67-73
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• 2007

Anhui Province, with a total north-south length of 570km and an east-west width of 450km and a total area of 139.6 thousand km2, accounts for 1.45% of China's total area. The landform and land feature of Anhui Province is diverse, and generally it can be divided into 5 natural regions: (1) Huaibei Plain; (2) Jianghuai Hillocks; (3) Dabie Mountains in the West of Anhui Province; (4) Yanjiang Plain, (5) Mountain Area of southern Anhui Province. Anhui Province is located in the transitional zone of warm and humid zone and subtropical zone, and its mean annual precipitation is 800-1800mm. The province, which has diverse climate, multiple land forms and many rivers and lakes, passes three basins (Huaihe River, Yangtze River and Xin'an River) and has large differences in the time distribution and regional distribution of water resource. Therefore, the development and usage conditions of the water resource in different regions are different.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.4
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• pp.31-38
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• 2002

The rate of sewage treatment in South Korea was 68% in the late 1999. Sewage treatment is mostly made near big cities such as Seoul and Busan, and it is little in rural areas. Wastewater from households goes to streams directly without treatment in rural areas and pollutes streams. It is necessary to improve the progress for treatment of nutrients such as N and P which cause eutrophication in streams and lakes, because sewage treatment system in South Korea focuses on treatment of basic organic matters. Therefore it will contribute to improve discharged water quality if small sewage treatment systems by aquatic plants and microbes are introduced to rural areas where are not connected to local sewage treatment facility. This experiment was conducted to find out the best way using aquatic plants and microbes to purify wastewater from households through individual sewage treatment system. Phragmites communis, Iris pseudoacorus, Acorus calamus var. angustatus, Typha orientalis and Oenanthe javanica were used for this experiment. BOD, COD, SS, T-N and T-P were analyzed following standard methods for wastewater. The result shows that wastewater was roughly purified through pebbles and sands, and highly purified through aquatic plants and microbes especially in T-N and T-P. Iris pseudoacorus is the most effective in reduction of COD and BOD level. This system will work even in winter when plants die because microbes will be still working.

• Progress in Superconductivity and Cryogenics
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• v.22 no.2
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• pp.1-6
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• 2020

Large-scale civil engineering works discharge a large amount of soil suspension contaminated with natural heavy metals. Most of the heavy metal ions due to industrial activities and minings are accumulated in the soils and the sediments of lakes and inner bays through the rivers. It is necessary to remove heavy metals from the soils and the sediments, because some of these heavy metals, such as arsenic and cadmium, have significant biological effects even in small amounts. This study proposes a new volume reduction method of the contaminated soils and sediments by superconducting magnetic separation. Our process can remove the specific minute minerals selectively, which adsorbs heavy metals depending on pH. As a fundamental study, the adsorption behaviors of arsenic and cadmium on minute minerals as a function of pH were investigated, and the adsorption mechanism was discussed based on the crystal structure and pH dependence of surface potential in each minute minerals.

• Journal of Environmental Science International
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• v.12 no.2
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• pp.163-170
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• 2003

Seosan A, B area is located on 36°42' of north parallel and 126°27' of east longitude. It consisted of broad artificial lakes and reclaimed agricultural lands; there is Ganwalho lake in A area and Bunamho lake in B area. Total birds surveyed four times in 2001 at the A area are 105,580 of 11 orders, 28 families, 89 species. Among them, resident species were 21 species including Pica pica. Twenty species including Cuculus canorus were summer migrants, and 30 species including Platalea leucorodia were winter migrants. Seventeen species including Limosa limosa were occasionally species. And Rostratula benghalensis was an unconfirmed species. Species diversity index (H') was 0.72; species equally common index (e/sup H'/) was 2.06. In January, maximum observed 102,121 individuals. However in July 52 species were observed most variously. There were total 81,152 birds observed with 11 orders, 22 families, and 71 species at the B area. Fifteen species including Falco tinnumculus were resident species. Summer migrants were 18 species including Ixobychus sinensis. Winter migrants were 25 species including Ciconia boyciana. Thirteen species including Tringa glareola were occasionally species. Species diversity index (H') was 0.281; species equally common index (e/sup H'/) was 1.325. In January, maximum observed 78,433 individuals. However in Silly 42 species were observed most variously.

• Journal of Integrative Natural Science
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• v.15 no.3
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• pp.111-122
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• 2022

The purpose of this study was to investigate the ecological impact of wetlands by changing the species diversity of benthic macroinvertebrates and birds following the creation of an artificial wetland with a size of 30 m*30 m on bare land in reclaimed land in Haenam-gun, Korea. We investigated monthly fauna of benthic macroinvertebrates and birds in and outside wetlands and physicochemical indicators for 7 months from March to September 2014. During the study period, the water temperature and dissolved oxygen levels were consistently higher in wetlands than lakes. Many species of benthic macroinvertebrates were observed in summer (16 species in July) due to seasonal effects, and the species diversity index was highest in July and then gradually decreased. Thirteen species of birds were observed in March, 6 species in April, 5 species in July, and 1 species in June, where most winter birds and migratory birds were observed around wetlands in spring. The species diversity index also decreased after being high in July except for spring. This suggests that the abiotic environment in the wetland can be improved by creating an artificial wetland in the reclaimed land, and the increase in benthic macroinvertebrates can ultimately be a basic direction to restore the wetland ecosystem in the reclaimed land.

• Korean Journal of Ichthyology
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• v.25 no.2
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• pp.135-140
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• 2013

Microphysogobio koreensis, an endemic Korean freshwater fishes belonging to Cyprinidae, is protected as a 2nd grade of endangered fishes by the ministry of the Environment. For this species, the study on the spawning microhabitat including structure of streambed and spawning grounds was carried out. The streambed that this species mainly lives consists of boulders, cobbles, and pebbles, the so-called Bb type, with a depth of 0.3 to 1.0 m and a rapid velocity of $0.5{\pm}0.2$ m/sec. But the main spawning grounds where the spawning is actually occurring, is relatively shallower, $0.4{\pm}0.1$ (0.4~0.6) m depth, and faster, $0.8{\pm}0.1$ (0.6~0.9) m/sec velocity, whereas the region that the fertilized eggs are attached are rather slowest to 0.4m/sec. The spawning starts at a water temperature of $20^{\circ}C$ in earlier May, laying their eggs on the cobbles' or boulders' surface or in between them. In particular, with a wide range of streambed structures, natural spawning grounds' environments may let the fertilized eggs not be swept from rapid current and secure efficient dissolved oxygen. The individuals, however, do not appear at the grounds any more after the spawning season, and it is expected that they may move into deeper water such as Lakes or lower streams.

• The Journal of Natural Sciences
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• v.12 no.1
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• pp.85-101
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• 2002

Landscape civilization in Korea originated in Cochosun(Ancient Chosun) era, this again succeeding to the period of the Three States - Koguryo, Baekje and Silla. The distribution of this culture showed great progress with the association of two particular religions - Buddhism and Confucianism.. Landscape development in Korea has greatly changed during specific times of both cultural and political upheaval in various societies. Religion has had a great deal of influence on landscape development. Traditionally Korean people have had a tendency to favor more natural landscape than man-made structures in landscape : This trend was a quite different concept from that of other oriental countries, not to mention of western countries. In particular, Buddhism influenced natural landscape, far from artificial craftsmanship in landscape. Oriental garden is a typical 'tabloid edition' of natural landscape which consists lakes, islands, ponds, stone monuments, and fruit trees, quite often raising animal in parks and courtyard style house. This style of garden influenced in Chosun Dynasty landscape. Landscaping was usually for royal gardens, cemetery parks or high level of officer's residence. However, landscaping in Chosun Dynasty which had established Confucianism as a state religion gave us a specific designation. It was neither ethnic imitation of the garden style of both China and Japan : People were used to enjoy nature-friendly landscape or sink into the ecstasy of natural scenery itself. The trend that landscape or establishing garden had been aimed at royal family- or bureaucrat-centered formatives was to become an obstacle to the development of landscape techniques in Korea. An example represented in a beautiful garden with fabulous decoration which established in places. This was completely not fit for the nation's feeling.

• Parasites, Hosts and Diseases
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• v.56 no.2
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• pp.205-210
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• 2018

Waterborne parasitic protozoa, particularly Giardia lamblia and Cryptosporidium spp., are common causes of diarrhea and gastroenteritis worldwide. The most frequently identified source of infestation is water, and exposure involves either drinking water or recreation in swimming pools or natural bodies of water. In practice, studies on Cryptosporidium oocysts and Giardia cysts in surface water are challenging owing to the low concentrations of these microorganisms because of dilution. In this study, a 3-year monitoring of Cryptosporidium parvum, Giardia lamblia, and Naegleria fowleri was conducted from August 2014 to June 2016 at 5 surface water sites including 2 lakes, 1 river, and 2 water intake plants. A total of 50 water samples of 40 L were examined. Cryptosporidium oocysts were detected in 22% of samples and Giardia cysts in 32%. Water at the 5 sampling sites was all contaminated with Cryptosporidium oocysts (0-36/L), Giardia cysts (0-39/L), or both. The geometric mean concentrations of Cryptosporidium and Giardia were 1.14 oocysts/L and 4.62 cysts/L, respectively. Thus, effective monitoring plans must take into account the spatial and temporal parameters of contamination because they affect the prevalence and distribution of these protozoan cysts in local water resources.