• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.19 no.1
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• pp.41-52
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• 2014

The impact of freshwater discharge on plankton was investigated in a semi-closed Cheonsu Bay during the rainy season. Field observations for environmental factors (seawater temperatures, salinities, chlorophyll a concentrations and nutrient concentrations) and zooplankton sampling were carried out from June 27 to September 1, 2012 at about 10 days interval. The relationship between the measured parameters and estimated values of zooplankton abundance were examined. After freshwater discharge, nutrient concentrations increased up to about twice and resultant increase of chlorophyll a followed within about 10 days. Both positive and negative impacts on zooplankton were observed. Positive one was the numerical response of zooplankton on this increased food supply, and negative one was the increased mortality caused by sudden changes in salinity. Maximum mortality of copepods was found to be up to 40%, although fast sinking of carcass made it difficult to estimate reliable mortality caused by salinity shock.

• Journal of Korean Society for Atmospheric Environment
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• v.17 no.3
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• pp.289-297
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• 2001

From March 1998 to February 1999, we observed visibility and weather change in Dae Chung Bong and Kwon Keum Sung three times a day; at 10 Am, 1 PM and 4 PM. During research period (357 days for Kwon Keum Sung, 351 days for Dae Chung Bong), clear days were 185 days(52%) in Kwon Keum Sung and 149 days (43%) in Dae Chung Bong. Months that had many clear days in a year were December and January in both area. The rate of clear day to cloudy day in Sokcho downtown and Dae Chung Bong was 5 to 5, 4 to 6, respectively. The number of cloudy day in a year in Dae Chung Bong was 34days more than in Sokcho downtown. The visual distance in Kwon Keum Sung was 12.2km on the clear day, and 3.3km on the cloudy day. The yearly average was 7.9km. And we can see 8.9km farther on the clear day. The visual distance in Dae Chung Bong was 13.3km on the clear day, and 3.1km on the cloudy day. The yearly average was 8.1km. The visibility of clear day was 10.2km longer than that of cloudy day. The percentage to observe East Sea clearly was about 70% between December and January in both areas, and showed the highest visibility during research period. We observed Mt. Keumkang from 3 to 6 times in a month except rainy season. The yearly average visibility was 2%. If you go Mt. Serok except April, when there was yellow duet cloud from China, and rainy season (between the last of June and early of September), you can appreciate the most beautiful Mt. Sorak with Mt. Keumkang.

• Journal of the Korean GEO-environmental Society
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• v.8 no.4
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• pp.67-74
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• 2007

Many studies for slope stability studies have indicated that the infiltration of rainwater into a slope decrease the slope stability. In order to minimize damage caused by slope failure, most design codes suggest that the slope stability be analyzed by saturated condition during rainy season. However it would be excessively conservative condition that every soil slope is saturated in rainy season irrespective of rainfall intensity, soil type and slope geometry. In addition, because most soil slopes are in an unsaturated state, it is necessary to consider the unsaturated characteristics of slope. This paper suggests a prediction method of saturation time for the weathered granite soil slopes due to rainfalls. The finite element analysis of transient water flow through unsaturated slope was used to investigate effects of soil-water characteristics, permeability at saturation, slope geometry, and rainfall intensity. From the result of these analyses, the prediction charts considering soil-water characteristics, permeability at saturation, and slope height were proposed in this study. It is possible to the time required to be saturated slope after rainfall.

• Journal of The Korean Society of Agricultural Engineers
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• v.63 no.5
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• pp.1-11
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• 2021

Soil moisture plays a critical role in hydrological processes, land-atmosphere interactions and climate variability. It can limit vegetation growth as well as infiltration of rainfall and therefore very important for agriculture sector and food protection. Recently, due to the increased damage from drought caused by climate change, there is a frequent occurrence of shortage of agricultural water, making it difficult to supply and manage stable agricultural water. Efficient water management is necessary to reduce drought damage, and soil moisture management is important in case of upland crops. In this study, soil moisture was calculated based on the water balance model, and the suitability of soil moisture data was verified through the application. The regional soil moisture was calculated based on the meteorological data collected by the meteorological station, and applied the Runs theory. We analyzed the spatiotemporal variability of soil moisture and drought impacts, and analyzed the correlation between actual drought impacts and drought damage through correlation analysis of Standardized Precipitation Index (SPI). The soil moisture steadily decreased and increased until the rainy season, while the drought size steadily increased and decreased until the rainy season. The regional magnitude of the drought was large in Gyeonggi-do and Gyeongsang-do, and in winter, severe drought occurred in areas of Gangwon-do. As a result of comparative analysis with actual drought events, it was confirmed that there is a high correlation with SPI by each time scale drought events with a correlation coefficient.

• Ocean and Polar Research
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• v.44 no.2
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• pp.127-137
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• 2022

This study examined the growth pattern and environmental factors affecting the growth of the halophyte, Suaeda japonica, which is prevalent on tidal flats in the west coast of Korea in order to calculate annual carbon production. Quantitative sampling was conducted every month for three years from 2018 to 2020 on salt marshes located on the southern coast of Ganghwa Island. In terms of annual density affected by the germination rate at first period, especially when air temperature for winter time was constantly below 0℃ for long periods of time, germination decreased and precipitation in summer also exerted an influence. In terms of annual growth with regard to length, the part below the ground grew rapidly in the beginning after budding, while the part above ground grew at a relatively steady rate at all times. With regard to biomass, the part below the ground also increased from April in a manner similar to length growth, but decreased drastically from September with leaves falling off and water loss occurring. The part above ground showed a rapid increase from the beginning of the rainy season. Size-frequency distribution revealed broader patterns after the rainy season as individual growth varied, but from September, it stopped at all year. High growth rates were recorded in the initial phase of growth after budding and growth was rapid, but growth declined in summer when biomass increased. The annual mean production based on growth rate was calculated at 352 gDWt/m²/yr, and the highest production was 519 gDWt/m²/yr in 2018, but it has decreased since 2019. Annual carbon production was at calculated 143.41 gC/m²/yr for Suaeda japonica in the vicinity of the southern coast of Ganghwa Island.

• Parasites, Hosts and Diseases
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• v.61 no.2
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• pp.163-171
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• 2023

The present study aimed to determine the infection status of trematode metacercariae and adults in cyprinoid fish from the Khun Thale Swamp in Surat Thani, Southern Thailand, with epidemiologic and faunistic viewpoints. In 2020, 577 fish in 15 species were collected in the summer (February-April) and rainy (September-November) seasons. Fish were individually examined for trematode metacercariae in the whole body and adults in the gastrointestinal tract using a stereomicroscope. Three species of digenetic trematode metacercariae, i.e., Haplorchis taichui, Haplorchoides mehrai, and Centrocestus formosanus, were detected in the muscle, fin, and/or scale of fish. Two species of adult flukes, including Rohdella siamensis and Helostomatis cyprinorum, were collected in the intestines. The prevalence of overall trematode infections was 32.4% (187/577 fish), which was higher in the rainy season (41.4%; 118/285) than in the summer season (23.6%; 69/292). The metacercariae of H. taichui and H. mehrai were detected in 7 fish species each, and those of C. formosanus were found only in Rasbora toneri. The aspidogastrean trematode R. siamensis (adult) was detected in Babonymus gonionotus. A digenean species, H. cyprinorum (adult), was found in Labiobarbus siamensis and Osteochilus vittatus. The present study has first confirmed that the metacercariae of heterophyid flukes, including H. taichui, H. mehrai, and C. formosanus, and adults of R. siamensis (Aspidogastrea) and H. cyprinorum (Digenea) are infected in some species of the cyprinoid fish from the Khun Thale Swamp in Surat Thani, Thailand.

• Animal Bioscience
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• v.37 no.2
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• pp.295-302
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• 2024

Objective: The aim of this study was to assess the effect of Thai native cattle grazing in the lowland or mountain forest on carcass characteristics, meat quality, sensory palatability, and chemical composition. Methods: Twelve male Thai native cattle with an average weight of 110±10 kg are allowed to be grazing in the lowland or Phu Phan mountain forest during the rainy season in northeastern Thailand. Results: The carcass characteristics, meat pH, and meat color were unaffected by treatment (p>0.05). The boiling loss was lower in the cattle grazing on the mountain forest (p = 0.027). The cattle grazing in the mountain forest had increased shear force (p = 0.039), tenderness (p = 0.011), and flavor intensity (p = 0.003). The protein and fat were higher (p<0.001 and p = 0.035, respectively) in cattle grazing in the mountain forest. The different grazing systems of the cattle had no effect (p>0.05) fatty acids in meat, except for capric acid (C10:0) and lauric acid (C12:0), which were higher (p = 0.046 and p = 0.049, respectively) when the cattle were grazing in the mountain forest. The different grazing systems did not influence (p>0.05) the unsaturated fatty acids in meat. Conclusion: Thai native cattle grazing in the Phu Phan mountain forest in the rainy season improves meat quality, sensory evaluation, and chemical composition.

• Journal of the Korean Society of Tobacco Science
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• v.9 no.1
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• pp.11-17
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• 1987

KA 101 and Xanthi-Basma were cultivated in Korea and Greece to compare the respective responses to environment and cultivation method on their growth characteristics and some properties of harvested leaves during 1984 and 1985. The contents of clay, calcium, organic matter and pH were higher in the soil of greece than that of Korea. Sunshine hours and precipitation in Greece during harvest and curing season were 8.6 hours per day and 53.3mm compared to that of 3.8 hours per day and 320mm in Korea, respectively. The plant height, leaf size and yield decreased, and days to flower was shorter 8-11 days in greek grown plants. The dehydration and curing process in Greece was linear and rapid due to the constant daily change of temperature and relative humidity with dry weather during curing season during curing season. But those process in Korea was variable and tardy due to rainy weather. Cured leaf ratio increased with upper stalk leaves in Greece but it was rather lower at top stalk position in Korea. The harvested green leaf cultivated in Greece showed higher contents of petroleum ether extract, total nitrogen and nicotine, but lower contents of reducing sugar and lower ratio of protein nitrogen to total nitrogen than in Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.3
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• pp.219-224
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• 1996

Silage comkv, suwwn 19). sorghum $\times$ sudangrass(p. 988) and winter ryeNaton) were cultivated on imperfectly drained paddy field under two different draining methods, subsurface darinage by PVC pipes and open ditsched surface drainage. The crops were harvested at the stage of hard dough for corn and soft dough for wrghum and rye. The soil physical properties. soil colors. soil structure and soil wetness were improved in the subsurface drainage. Gravitational water table occured depth in 110 cm(dry season)~75cm(rain season). In soil profile description, yellowish brown with yellowish red mottles and well developed granular structure were found in the surface A horizon. The portion of solid phase in subsoils(B horizon) was reduced from 48.6%(undrained) to 43.7 %. A blocky structure with dark gray to gray were described in the open ditsched surface drainage. Severe wet depression of the crops was observed due to it's higher moisture contents, where the gravitational water occured depth in 25~37cm during the rainy season. The chemical properties of paddy soils were less affected by drainage methods. The concentration of available phosphate. organic matter and exchangeable K, Ca and Mg were decreased in the subsurface drained soils. The annual dry matter yields of com-rye cropping were 17.8 ton in the undrained, 21.6 ton in the open ditsch drainage and 35.9 ton/ha in the subsurface drainage.

• Advances in environmental research
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• v.2 no.1
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• pp.51-60
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• 2013

The paper aims to characterise the waste generated in municipality of Varanasi, the most populated city in the state of Uttar Pradesh, India. MSW is a heterogeneous waste and composition of the waste varied from season to season. The generation, collection and management of waste have become a major environmental problem in most of the developing cities. MSW was collected from open dumping grounds for 2 consecutive years. Each year was classified into 3 seasons of 4 months. On analysis it was found that the biodegradable fraction is always more than other fractions with a minimum of 48.25% in rainy season. With such a high fraction of biodegradable wastes, options such as composting and biomethanation could be tried to convert waste into energy. The average weight of waste generation at present is 0.460 kg per capita per day. The study showed that waste generation and collection were increasing every year, which may be attributed to increase in population.