• Korean Journal of Environment and Ecology
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• v.34 no.2
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• pp.121-129
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• 2020

This study investigated the change of benthic macroinvertebrates community due to erosion control dams installed in Wonju, Gangwon by comparing the data before and after a rainy season. It selected a closed-type erosion control dam (boulder stone), an open-type erosion control dam (buttress), and a control area and surveyed two upstream points and two downstream points four times between March and September 2019. The flow velocity mostly increased in the closed-type, open-type, and control areas but decreased in St. 3 after the rainy season. The number of benthic macroinvertebrates species and their populations mostly decreased after the rainy season, and the rate of decrease in the populations in the open-type and control areas were more similar than the closed-type area. Species and populations of the EPT groups mostly decreased after the rainy season. A result of the similarity analysis showed that the closed-type and open-type areas were separated by 38.4% with the control area before the rainy season, but the open-type and control areas were separated by 51.3% with the closed-type area after the rainy season. A result of the principal components analysis (PCA) based on axis 1 showed that the closed-type area had a positive value before and after the rainy season, and the open-type and control areas had a negative value before and after the rainy season. The open-type area was more correlated with the control area than the close type. The analysis of the EPT groups showed the distribution of Ephemeroptera in the closed-type area and Trichoptera in the open-type and control areas. The result of this study shows that the installation of erosion control dam can cause changes in benthic macroinvertebrates community and that the open-type area had a smaller difference community difference from the control area after the rainy season than the closed-type area.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.1
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• pp.63-67
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• 2004

In order to evaluate the nutritive value of the forage plants in South Sulawesi, Indonesia, 266 samples (61 grasses and 65 legumes grown in the dry season, 60 grasses and 80 legumes grown in the rainy season) were collected from the highland and the lowland in 1998 to 2000, and were subjected to the determination of mineral composition. The mean contents of Ca, Mg, P, Na and K in grasses were 0.6, 0.3, 0.5, 0.1 and 2.3%, respectively, and in legumes were 1.8, 0.5, 0.8, 0.1 and 1.7%, respectively. The least-squares analysis of variance demonstrated as follows; For the grasses, Ca content was significantly affected by the year${\times}$season, year${\times}$altitude, and the season${\times}$altitude interactions. Mg content was significantly affected by year and season and P content was significantly affected by altitude, year and by the year${\times}$altitude interaction. For the legumes, Ca content was significantly affected by altitude and the year${\times}$season, season${\times}$altitude and the year${\times}$altitude interactions and Mg content was significantly affected by season or altitude and by the year${\times}$season interaction. These results indicate that Ca content of forage plants grown at the lowland in rainy season was higher than at the highland in dry season. Mg content of forage plants grown at the lowland in dry season was higher than at the highland in rainy season and P content of forage plants grown in the highland was higher than in the lowland.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.334-337
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• 2003

The results of this numerical model is usable to analysis for the phenomena of precipitation during the periods of a rainy season in the Northeastern Asia. Case l(start of rainy season) dominates over precipitation by the processing of convection from the equator region through the East China region, and then the most of water vapor is transported by the processing of advection from the India-monsoon region to this study region. Case 2(heavy rainy season) faints precipitation by the processing of convection in the Korean peninsula, but dominates precipitation by the processing of microphysics. the water vapor originates from the India-monsoon region.

• Proceedings of the Korean Geotechical Society Conference
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• 2010.03a
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• pp.921-926
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• 2010

To examine saturation characteristics of an unsaturated soil in the steep slope area with collapse, it separated dry season from rainy season and measured water content and permeability, and measured permeability by using a tension infiltrometer in the site. In addition, it conducted electrical resistivity survey to look into thickness of ground and geological structure of underground. The collapsed slope increased depth of weathered zone compared to upper slope, and there electrical resistivity anomalous zone caused by the filtrated underground water was observed. The permeability of the collapsed area was observed high compared to upper and lower slopes of retarding basin without collapse, and the permeability measured by dividing the dry season and rainy season was measured high in case of dry season.

• Corrosion Science and Technology
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• v.2 no.4
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• pp.183-188
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• 2003

Corrosion of carbon and weathering steels were evaluated under 3 environmental exposures in Thailand (urban, rural and marine) for a year. The seasonal study was designed to determine different corrosion mechanisms by 6 months of dry season and 6 months of rainy season in a year. The sheltered exposure racks were used to determine the washing effect of min. At each site, climatic and pollutants analyses were carried out. The present study showed that the difference in corrosion rates of carbon and weathering steels was not so distinguished in both rural (AIT) and urban (TISTR) environments. The corrosion rate of weathering steel was somewhat lower than that of carbon steel and the decreasing tendency of corrosion rate with time was slightly higher for weathering steel than for carbon steel. In marine (Rayong) environment, the corrosion rate was higher and the effect of wet and dry seasons was observed. The corrosion rate in 6 dry months was higher for direct exposure than for sheltered exposure. However, in 6 rainy months. the corrosion rate of sheltered exposure was higher than that of direct exposure. In direct exposure for I year, that is, the first 6 dry months and the next 6 rainy months, the corrosion rate decreased with time. but in sheltered exposure, the corrosion rate did not decrease with time. instead, increased in the next 6 rainy months. This indicated that the protect ive layer formed in the first 6 dry months could be destroyed by high deposition of chloride to r sheltered exposure in the next 6 rainy months; whereas the rust layer for direct exposure could be kept sound due to washing effect in rainy season, even though the deposition rate of chloride was almost the same for direct and sheltered exposures. In marine environment, the weathering steel showed higher corrosion resistance than carbon steel but its corrosion rate was higher than those in other environments.

• Korean Journal Plant Pathology
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• v.11 no.3
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• pp.197-209
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• 1995

This paper is a third report about the new fungal diseases of economic resource plants in Korea. It contains short descriptions on symptoms, occurrence conditions, pathogen, and some phytopathological notes for each of 10 fungal plant diseases. They are angular leaf spot of Achyranthes japonica by Cercospora achyranthis causing leaf spot and defoliation in the shade of plants, leaf spot of Armoracia lapathifolia by Cercospora armoraciae causing leaf spot to blight from the rainy season to autumn, hypophyllous mold of Dioscorea tokoro by Distocercospora pachyderma causing leaf spot and yellowing, hypophyllous mold of Artemisia spp.by Mycovellosiella ferruginea causing leaf spot and yellowing, angular leaf spot of Aralia elata by Pseudocercospora araliae causing velvety leaf spot and defoliation, hypophyllous mold of Lycium chinense by Pseudocercospora chengtuensis causing velvety leaf spot and defoliation from the rainy season to autumn, angular leaf spot of Diospyros lotus by Pseudocercospora disospyri-morrisianae causing leaf spot and defoliation from summer to autumn, brown leaf spot of Impatiens textori by Pseudocercospora nojimae causing leaf spot to blight from the rainy season, leaf spot of Cephalonoplos segetum by Ramularia cirsii causing leaf spot to blight throughout the growing season, and white mold of Leonurus sibiricus by Ramularia leonuri causing leaf spot to blight mostly in autumn.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.528-530
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• 2002

The study was designed to evaluate the seasonal influences on cross-bred cow milk composition and paneer yield in Dhauladhar mountain range of sub-himalayan region. Fifty samples from each season were collected from a herd of $Jersey{\times}Red\;Sindhi{\times}Local$ cross-bred cows during summer (April-June), rainy (July-September) and winter (November-February) and analyzed for fat, total solids (TS) and solids not fat (SNF). Paneer was prepared by curdling milk at $85{\pm}2^{\circ}C$ with 2.5 per cent citric acid solution. Overall mean for fat, TS and SNF content of milk and paneer yield were 4.528, 13.310, 8.754 and 15.218 per cent respectively. SNF and TS content varied among seasons being highest in winter (8.983% and 13.639%) followed by summer (8.835% and 13.403%) and lowest in rainy season (8.444% and 12.888%). Paneer yield was lowest (14.792%) in rainy season and highest (15.501%) in winter season.

• Journal of Korean Society on Water Environment
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• v.27 no.4
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• pp.397-404
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• 2011

This research investigates the runoff characteristics of refractory organic matters from Kyongan river watershed. Samples were taken 27 times during dry season, 4 times during rain events and analyzed into flow rate, Dissolved Organic Carbon (DOC), Particulate Organic Carbon (POC), Refractory Dissolved Organic Carbon (R-DOC), Refractory Particulate Organic Carbon (R-POC). R-DOC during dry season was the lowest in winter and showed a rising tendency in spring and R-POC changes less than R-DOC. The mass loading of Refractory Total Organic Carbon (R-TOC) in summer takes approximately 80% of 1 year mass loading. During rainy season, EMC of R-DOC was similar to R-DOC in dry season. But maximum EMC of R-POC was 12 times higher than that of R-POC in dry season. Results of the survey show that enhanced management of R-DOC in dry season and R-POC in rainy season is needed.

• Korean Journal of Environmental Agriculture
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• v.31 no.3
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• pp.235-247
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• 2012

BACKGROUND: Gohyeon Stream is the municipal eco-stream of 7.1km in total length which flows through the downtown area of Gohyeon in Geoje city, rising from the watershed of Mundong Water Fall. Gohyeon district in Geoje city has been a rapid growing area centering in Geoje city and then experienced an rapid increase in population. Large amounts of sewage pollutants have been spewed into Gohyeon Stream from its tributaries, due to the lack of sewer system. Gohyeon Stream is laced with unhealthy levels of fecal coliform (FC). Restoration of water quality in Gohyeon Stream is no less inevitable in behalf of its ecosystem and the citizen. In this study, the water quality of Gohyeon Stream and its tributaries was examined temporally and spatially, and their relationships were comparatively analyzed to give useful basic data applying to a restoration project of the water quality of Gohyeon Stream. METHODS AND RESULTS: The samples ware taken at 20 points in Gohyeon Stream and 19 points in its tributaries during the rainy and dry seasons, respectively, and examined on the parameters of pH, temperature, salinity, dissolved oxygen (DO), suspended solid (SS), biochemical oxygen demand (BOD), chemical oxygen demand (COD), dissolved inorganic nitrogen (DIN; $NH_3$-N, $NO_3$-N, $NO_2$-N), disolved inorganic phosphorus (DIP; $PO_4$-P) and FC. The data were analyzed using a comparative analysis and Pearson's correlation analysis among the parameters. During the rainy season, the concentration of SS was high in the upper region of Gohyeon Stream, and the concentrations of COD, DIN and DIP were low in the upper region and high in the middle and lower regions. During the dry season, the concentration of SS was low and the concentrations of COD, DIN, DIP and FC were high in all regions. The Pearson's correlation analyses showed that the relationships between DO and FC, COD and DIP, and DIN and FC during the rainy season as well as between DO and DIN, SS and FC, COD and DIP, and DIN and DIP during the dry season were significant. CONCLUSION: During the rainy season, the upper region of Gohyeon Stream flowed the high level of SS, the middle region the high level of nutrients due to an agricultural run-off, and the lower region the high level of nutrients due to a sewage inflow. During the dry season, the water quality of Gohyeon Stream was directly and sensitively influenced on the inflow of sewage from the tributaries.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.4
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• pp.344-350
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• 1998

Seasonal variations in the feeding behaviour of Jamunapari and Barbari goat breeds and their utilization of browse and grass nutrients was evaluated in a promising 3-tier (Leucaena leucocephala- Dichro-stachys nutan-Cenchrus ciliaris) reconstituted pasture during summer, rainy and winter season of the years 1987 and 1988. Distinct diurnal pattern of feeding was observed with both the breeds. Jamunapari goats spent significantly more time foraging during winter season (352.0 min) followed by summer (306.0 min) and least in rainy season (277.0 min). Though no significant difference was observed in the relative time spent by Barbari goats on grazing activities during summer and winter season, they spent significantly more (p < 0.05) time during rainy season as compared to other two seasons. The preference of grazing goats for certain plant species in relation to others was evident with distinct seasonal and breed variations. DM intake (g/kg $BW^{075}$) varied significantly (p < 0.05) from season to season. Among the browse. L. leucocephala was prefered over D. nutan irrespective of breed over the seasons. There was no breed difference in DM intake, or proximate composition and nutrient digestibility of ingested herbage. The available nutrient content of ingested forage was found sufficient to meet the nutrient requirements of adult goats for maintenance (NRC, 1981). The reconstituted 3-tier pasture dominated by plant species like L. leucocephala and Cenchrus species appear to have great potential to sustain the nutrient requirement of goats without adverse seasonal fluctuations in pasture quality.