• 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.22 no.3
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• pp.416-420
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• 2009

An experiment of one-year duration was conducted on sixteen adult male German Angora rabbits under sub-temperate Himalayan conditions, to assess the effect of seasons on their body weight, wool production and quality, plane of nutrition and the digestibilities of nutrients. The daily meteorological attribute viz. minimum and maximum temperature; relative humidity and rainfall were recorded during winter (October to March), summer (April to June) and rainy (July to September) seasons. Biological parameters viz. body weight at the time of shearing, wool yield of individual rabbit, quality attributes of wool, fortnightly dry matter intake, chemical composition of feed and fodder and digestibilities of nutrients were recorded. Average minimum and maximum ambient temperature during winter, summer and rainy seasons were 4.6${\pm}$1.9 and 21.4${\pm}$2.8; 13.6${\pm}$2 and 30.3${\pm}$2; and 20.0${\pm}$1.4 and $31.0{\pm}1.8^{\circ}C$, respectively. The average relative humidity and total rainfall during winter, summer and rainy season were 69.5${\pm}$2.9% and 74.7${\pm}$21.8 mm; 58.6${\pm}$2.2% and 38.1${\pm}$18.1 mm; and 69${\pm}$4.2% and 104.0${\pm}$43.7 mm, respectively. The body weight of rabbits increased during all seasons, however, the maximum average daily weight gain of 3.47${\pm}$0.1 g was observed during the rainy season. The wool yield differed significantly (p$\leq$0.05) among different seasons with highest (140.4${\pm}$10 g) and lowest (108.5${\pm}$6.9 g) during winter and summer, respectively. The wool yield during the rainy season was 123.3${\pm}$5.2 g. The wool quality attributes revealed non-significant differences for staple length, fiber diameter, medulation percent, percent pure fibers and percent guard hairs. Plane of nutrition revealed significant (p$\leq$0.05) differences for concentrate intake. The concentrate intake was highest during winter (124.4${\pm}$2.6 g) followed by summer (86.8${\pm}$8.9 g) and rainy (80.7${\pm}$11.8 g) seasons. The reverse trend was observed in roughage intake with significantly (p${\leq}$0.05) lower intake during winter and highest during summer months. As a result total dry matter intake during different seasons was similar. Significant differences (p${\leq}$0.05) were observed for digestibilities of crude protein, crude fiber, ether extract, acid detergent fiber and cellulose. Digestibility of crude protein was highest during winter whereas the digestibilities of crude fiber, ether extract, acid detergent fiber and cellulose remained higher during the rainy season. During the winter season, the dry matter used for producing 100 g of wool was substantially lower than during other seasons and was concluded to be the best season for production of Angora wool under subtemperate Himalayan conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.6
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• pp.708-718
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• 2010

The objective of the current study was to determine seasonal changes in glucose, cholesterol, non-esterified fatty acids (NEFA), serum inorganic phosphorous (SIP), calcium, magnesium and iron concentrations in Nguni and crossbred cattle on the sweet and sour rangelands of the Eastern Cape Province of South Africa. Body weights, body condition scores (BCS) and serum concentrations of energy-related metabolites and mineral profiles were determined in late cool-dry, hot-dry, hot-wet, post-rainy and early cool-dry seasons in 100 cattle raised on communal rangelands from August 2007 to May 2008. Nguni cattle had lower (p<0.05) and higher (p<0.05) serum concentrations of glucose in the hot-wet and post-rainy seasons, respectively, compared to crossbreds in the same seasons. Serum cholesterol and NEFA concentrations in Nguni were lower (p<0.05) than in the crossbreds. Nguni and crossbred cattle had higher (p<0.05) serum NEFA concentrations on the sweet rangeland during the late cool-dry season than on sour rangeland. Nguni cattle had higher (p<0.05) SIP concentration in the hot-wet season than the crossbreds. Generally, both breeds had lowest SIP concentration during the hot-wet season on the sour rangeland. The lowest magnesium and highest iron concentrations were observed in the hot-wet and post-rainy seasons, respectively, compared to other seasons. Cattle on the sour rangeland had lower (p<0.05) iron concentrations than those on the sweet rangeland. It was concluded that Nguni cattle had lower cholesterol and NEFA, and higher SIP concentrations in the hot-wet season than crossbreds and energy deficits mostly occurred during the late cool-dry season on the sweet rangeland.

• Journal of Korean Society on Water Environment
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• v.29 no.6
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• pp.739-745
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• 2013

This paper investigated the runoff characteristics of different properties of suspended solids in streams according to the watershed characteristics and dry/rainy season. Suspended solids were divided into VSS and NVSS depending on volatilization. The main results of this study were as follows. TSS were more correlated with NVSS than VSS. Suspended solids were positively related with the proportion of urban > paddy > upland, negatively related with forest cover. VSS were positively correlated with POP and POC. VSS, measured in dry season, would partly result from autochthonous production and could be an indirect indicator of organic suspended solids.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.03a
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• pp.1009-1019
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• 2009

Soil nailing method is widely used in reinforcing slopes and excavating earth. The analysis of nail-reinforced slopes, in order to determine the economical length ratio and nail angle, complicated analytical need to be applied by means of computer programs. Therefor this suggested Soil stability Chart for nailed slopes which may be very useful for pre-design, rapidly design, and final check. Three slope types, three nail length and three nail angles are selected for the stability analysis by using limit equilibrium method of Bishop and French Method. From the above results, this study propose the slope reinforced design charts for dry season and rainy season. This proposed reinforced design charts can check dry season as well as rainy season, also these charts can provide reinforcing requirement, soil nail's economical length ratio and nail angle as well.

• Membrane and Water Treatment
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• v.15 no.3
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• pp.99-106
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• 2024

This study developed an efficient management plan to improve the water quality by analyzing fluctuations in the ratio and amount of various organic substances in streams considering watershed characteristics and rainfall patterns. Monitoring was conducted on three streams and one lake over seven sessions during wet and dry seasons. Water quality indicators including total organic (TOC), refractory dissolved organic (RDOC), and particulate organic (POC) carbons were analyzed using high-temperature combustion oxidation. The three streams (Cheongmi, Yanghwa, and Bokha) displayed high TOC concentrations during the rainy season because the accumulated organic substances from the dry season were washed away by rainfall. By contrast, Paldang Lake exhibited a substantial decrease in TOC concentration due to dilution, which was influenced by watershed and rainfall characteristics. Across all streams and lakes, dissolved organic carbon (DOC) accounted for the highest proportion, at 77.5% of TOC, with RDOC making up 91% of DOC and 71% of TOC. Although POC contributed a small annual proportion to annual TOC, the concentration rapidly increased during late spring and early summer, with increases of 40.403%, 25.99%, and 27.388% in Cheongmi, Yanghwa, and Bokha, respectively. Continuous monitoring of RDOC is essential to identify seasonal fluctuations and changes due to rainfall events. Furthermore, intensive POC management during the rainy season, particularly in May and June, is potentially economical and efficient for water quality management.

• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.2
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• pp.71-78
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• 1987

This experiment was carried out to examine the effects of sowing method and summer management on the dry matter yield, dead matter, weed development and ground cover of orchardgrass (Dactylis glomerata L.) meadow. The experiment was allocated as a split-split plot design with three replications. The main plots were sowing method of drilling and broadcasting, sub plots were drainage of experimental field, adequate and inadequate, and sub-sub plots were cutting timeof orchardgrass, cutting before rainy season started and cutting after rainy season ended. The experiment was undertaken over a period of 14 months from September, 1983 to October, 1984. The results obtained are summarized as follows: 1. There were no significant differences in dry matter yield among treatments at the first cutting, but cutting before rainy season produced significantly more forage yield ($P{\le}0.01$) than cutting after rainy season at the second and third cuts. At the third cutting, drilled orchardgrass meadow showed a significant dry matter yield ($P{\le}0.05$) than broadcast orchardgrass meadow, 2. The dead matter of orchardgrass was accumulated only at the second cutting when orchardgrass meadow cut after rainy season. Orchardgrass produced in the adequate and inadequate drainage plots consisted 20.4 and 35.9% of dead material, respectively, but no significant difference was found between two drainage treatments. 3. Drilled orchardgrass meadow produced significantly less weeds ($P{\le}0.05$) than broadcast orchardgrass meadow, but the plots cut after rainy season produced significantly more weeds ($P{\le}0.01$) than the plots cut before rainy season. 4. The percent ground cover of orchardgrass in the plots cut before rainy season was significantly higher ($P{\le}0.01$) than that in the plots cut after rainy season at the second cutting. Drilled plots showed a slight increase in the ground cover than the broadcast, but the difference was not significant. The same trend of ground cover of the meadow estimated at the second cutting was sustained after the third cutting. 5. Based on the results of the experiment, it indicates that the second cut of orchardgrass should be made before rainy season related for maintaining high yield of the meadow. Drilling as a sowing method of orchardgrass meadow could be adopted in the view point of reducing weed development.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.4
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• pp.107-113
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• 2007

The Kuem-River, one of the largest rivers in Korea, is the primary water source for more than 4 million people in Kongju city and surrounding area. To study the effect of stormwater runoff to CSOs, twelve monitoring sites were selected in two large cities (City of Kongju and City of Buyeo) near the Kuem-River. Monitoring was reformed by collecting grab samples, measuring flow rates during dry and wet seasons during over two rainy seasons. Generally the flow rate of wastewater in combined sewers was rapidly decreased after 23:00 P.M. and gradually increased from 06:30 A.M. in all sites during the dry season. The concentrations of pollutant increase approximately 5 to 7 fold for TSS and 1.5 to 2.5 fold for BOD during the rainy season. Monitoring and statistical analysis show that the groundwater contributes on sewage volume increase (average 25-45% more) during dry periods and the stormwater runoff contributes approximately 51-72% increase during rainy periods. Generally the concentrations of combined sewage were more polluted during the first flush period than after the first flush during a storm event.

• Journal of Korean Society on Water Environment
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• v.27 no.3
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• pp.306-313
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• 2011

In this paper, runoff characteristics of South-Han river watershed in terms of refractory organic matters were investigated. The concentrations of DOC, POC, R-DOC, R-POC in runoff and flow rates were determined by monitoring 27 times in dry season and 4 times in rainy season. The concentrations of the dissolved refractory organic matter, R-DOC was the lowest in fall and similar in the other dry seasons. The particulate refractory organic matter, R-POC showed less fluctuation than R-DOC. In summer, mass loading was the highest than other dry seasons. The concentrations of R-DOC, R-POC were showed to be affected by runoff volume. The mass loading grows higher as runoff volume gets higher.

• Journal of Korean Society of Water and Wastewater
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• v.24 no.4
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• pp.443-451
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• 2010

This study was conducted to confirm the CSOs characteristics, and to estimate treatment efficiency of CSO treatment process. Flowrate was average $53,500m^3$/d, maximum $58,100m^3$/d during dry season, but after rain-fall, the flowrate was increased more than twice that of the dry season. And, water pollution concentrations, such as $COD_{Cr}$, SS, $BOD_5$, TN and TP of after rain-fall, were also increased. Thus, for more efficient treatment of pollutants during rainy season, The vortex separator and continuous fiber filter devices were used. From the results on particle range, removal efficiency of particle was 99.7% at the particle size range of $40{\sim}100{\mu}m$ but decreased as 55-80% at the below $40{\mu}m$. The removal efficiencies of $COD_{Cr}$, SS, TN and TP were approx. 70, 60, 70 and 50, respectively during the dry season and approx. 50, 50, 8 and 18% during the rainy season. Also, when compared with the primary sediment basin, $COD_{Cr}$, SS, TN and TP removal efficiencies were high. especially, at the case of TN and TP, TN was more removed than TP because of higher conversion factor value. But we needed more study for the injection of a coagulants to get more stable treatment efficiency for soluble pollutants. Consequently, This process can be used for CSOs treatment as well as replace the primary sedimentation basin during the dry season.