• Water Engineering Research
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• v.5 no.1
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• pp.17-36
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• 2004

This paper evaluated the water resources aspect of the operating results of the Daecheong Multipurpose Dam for the last 21 years. The elements that were evaluated included the amount of water supply from the dam. volume of outflow from the regulating dam, changes in the runoff volume at the dam site and downstream, and variations in the water supply capacity of the Daecheong Multipurpose Dam and the Geum River Barrage Dam situated in the estuary. The rainfall-runoff model was used to evaluate the changes in the runoff volume, and the water balance analysis system was used to evaluate the variations in the dams'water supply capacities. The volume of domestic and industrial water supply from the Daecheong Multipurpose Dam increased to 6.1 times for the last 21 years from 61${\times}$$10^6$$m^3$ in 1981 to 375${\times}$$10^6$$m^3$in 2001. The rate of outflow to inflow of the Daecheong Dam was analyzed 1.30 times in dry season, 1.12 times in semi-dry season, and 0.90 times in rainy season. The volume of inflow to the Geum River Barrage Dam down- stream after the dam's construction increased to 1.25 times in dry season and 1.02 times in semi-dry season and decreased to 0.94 times in rainy season. The water supply capacity of the estuary barrage dam almost did not change in cases with or without the Daecheong Multipurpose Dam, but storages were largely affected by the outflows of the Daecheong Multipurpose Dam.

• Journal of the Korean Society for Marine Environment & Energy
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• v.15 no.4
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• pp.314-322
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• 2012

In order to elucidate temporal variations of temperature, salinity, pH, dissolved oxygen (DO), suspended particulate matter (SPM), dissolved inorganic nutrients, and chlorophyll a, we performed 25-hour continuous monitoring in the Seomjin River Estuary in March (dry season) and July (rainy season) 2006. We also investigated spatial variations of marine environmental parameters across a saline gradient. In the Seomjin River Estuary, continuous monitoring results revealed that salinity variations were mainly affected by tidal cycle in the dry season and by river discharge in the rainy season. In the dry season, the spatio-temporal distribution of dissolved inorganic nutrient (nitrate, nitrite, and silicate) concentrations showed a good correlation with tidal cycle. While nutrient concentrations in rainy season showed not much variance in time. There were 6 and 4 times higher dissolved inorganic nitrogen and phosphorus concentrations in the rainy season than those in the dry season, respectively. Silicate concentration was 43 times higher in the rainy season than that in the dry season. Chlorophyll a concentration was higher in the dry season than that in the rainy season showing high nutrient concentrations. The results of this study, spatio-temporal variations of marine environmental factors are determined by both tidal cycle and river discharge. It seems that chlorophyll a concentration is related to the river discharge than dissolved inorganic nutrient distribution.

• 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.

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.330-330
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• 2016

The quantification of dry season evaporation in regions, where the magnitude of dry season flows is key to the regional water supply, is essential for good water management. Also, tree transpiration has a significant role in the water balance of a catchment whenever it is tree populated, especially in water limited environments. Such is the case in the Middle Mountains of Nepal where dry season flows play a significant role in downstream water provisioning and their proper functioning is key to the welfare of millions of people. This research seeks to study the transpiration of a pine forest stand in the Jikhu Khola Watershed in the Middle Mountains of Nepal. To the author's knowledge, no single study has been made so far to estimate the dry season evaporation from the planted forest stand in the Middle Mountains of Nepal. The study was carried out in planted pine forest embedded within the Jikhu Khola Catchment. Field campaigns of sap flow measurements were carried out from September, 2010 to February, 2011 in the selected plot of 15*15m dimension, to characterize dry season evaporation. This was done by measuring sap fluxes and sapwood areas over the six trees of different Diameter at Breast Height (DBH) classes. The sap flux was assessed using Granier's thermal dissipation probe (TDP) technique while sapwood area was determined using several incremental core(s) taken with a Pressler borer and immediately dyeing with methyl orange for estimating the actual depth of sapwood area. Transpiration of the plot was estimated by considering the contribution of each tree class. For this purpose, sap flux density, sapwood area and the proportion of total canopy area were determined for each tree class of the selected plot. From these data, hourly and diurnal transpiration rates for the plot were calculated for experimental period. Finally, Cienciala model was parameterized using the data recorded by the ADAS and other terrain data collected in the field. The calibrated model allowed the extrapolation of Sap flux density (v) over a six month period, from September 2010 to February 2011. The model given sap flux density was validated with the measured sap flux density from Grainier method.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.4
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• pp.193-200
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• 2007

The purpose of this study is investigate to water quality, pH, turbidity, salinity, nutrients, SS, DO, COD, ${NH_4}^+$-N, ${NO_2}^-+{NO_3}^-$-N, TN, TP, ${PO_4}^{3-}$-P in ditches and seawater of the Hwawon, southwestern coastal area of Korea. Two stations of the ditch, one station at outfall from reservoir of the coastal development and 15 stations of seawater were measured in August just after a 96.5 mm rainfall and in dry season of November 2006. The sampling time were divided into a rainy and dry season based on turbidity, SS, salinity and nutrients difference of distributions that was evidence as a inflow of pollutants from the developing coastal land area. The pH, turbidity, salinity and SS were high and showed different from between surface and bottom in near the developing of coastal land than the other stations after a strong rainfall over 90 mm while it were not varied in vertical and horizontal concentration profile in dry season. The other nutrients were showed the same concentrations gradient patterns. In opposition to expectations, the SS in dry season was higher than in the rainy season due to upwelling by the wind and strong current. It appears that the researched coastal seawater qualities were mainly effected by the inflow of freshwater from the ditches and drain from the reservoir of the developing land area during strong rainfall while the seawater qualities were mainly effected by the wind and strong current in dry season.

• Journal of Ginseng Research
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• v.15 no.1
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• pp.36-40
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• 1991

A field experiment was conducted to examine the growth of one and two year old American ginseng (Panax guinguefolium L.) in the arid interior of British Columbia, Canada. For both years of plants, early season growth was characterized by rapid stem and leaf dry matter production. Root growth commenced in early June and continued until early September. One year old roots had a dry weight of 0.1 to 0.2g at the end of the growing season. The two years old roots commenced the growing season at 0.Is and increased in dry matter by a factor of ten-fold. Dry to fresh weight ratios for both years were similar for root, leaf and stem samples at the end of the growing season. Leaf area index for both years showed similarities in progression over the growing season. As a consequence of the effectiveness of the microclimate modification employed to permit American ginseng cultivation (elevated shade cloth and surface mulch), plant growth and development was extremely good. This indicates the potential for the cultivation of American ginseng in dryland environments.

• 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.

• Journal of Environmental Science International
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• v.16 no.4
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• pp.459-466
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• 2007

To analyze the water characteristics in the dry and wet seasons, the data for temperature, salinity, nutrients and $chl-{\alpha}$ were used, which were observed in the south coastal area of Korea during April to October 2000. At Yeosu in the south coast of Korea, the higher values of 35.0 psu in salinity were shown in March and April, the lower values of 23.0 psu in salinity were shown in August and September. The annual range of salinity was 12.0 psu. The total amount of precipitation in the wet season (July to October) was occupied 68% (about 846 mm) during 2000. The precipitation of the dry season (November to June) was occupied 32% (about 394 mm) in the year In the coastal area, the salinity variation is distinct in the period of July to October. Based on this result, we divided the season into two parts: the dry season during April to June and the wet season during July to October. Factor analysis was shown that temperature has strong negative relation and nutrients show positive relations in the dry season by the factor 1, which explains the total valiance of 50.6% at the surface water. In the wet season, salinity has negative relation and nutrients show positive relation by the factor 2, which explains the total variance of 33.5%. The bottom layer also showed similar to those of surface water in the results of factor analysis. These mean that nutrients become rich due to the freshwater inflow in the wet season. The low saline water is shown not only in the south coast but also in the overall region in the South Sea of Korea. It is suggested that the South Sea of Korea may call a ROFI (Region of Freshwater Influence) system in summer.

• Journal of Ginseng Research
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• v.22 no.3
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• pp.161-167
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• 1998

American ginseng plants (Panax quinquefolium L.) of various ages were harvested every two weeks during each of three growing seasons and dry matter yield of components and root respiration determined. Shoot dry weight was about 0.5 g, 2.5 g and 4 g for 2, 3 and 4-year-old plants, respectively and fruit dry weight was as much as 50% of this in 3- and 4-year-.old plants. Root dry weight decrease by 30~50% as shoots emerged and at the end of the season was about 2 g, 3.5 g and 5 g in 2, 3, 4 and 5-year-old plants, respectively. Shoot and root dry weight were linearly related with an approximate 1:2 ratio. Root respiration rate at 2$0^{\circ}C$ in the dark was about 5 $\mu\textrm{g}$ CO2 g-1 DW(dry weight) min-1 in the early season, then doubled within 50 days as shoots emerged, and thereafter declined over the season to 2~5 $\mu\textrm{g}$ CO2 g-1 DW min-1. The Q10 for dark respiration over the interval from 10 to 2$0^{\circ}C$ was 1.58. Root respiration rate and shoot growth rate was positively linearly related in all ages of plants. Key words: Dry weight, partitioning.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.3
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• pp.335-342
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• 1994

This study was undertaken at Gowa, South Sulawesi, Indonesia, as part of a larger forage genetic resource evaluation project. The experimental program consisted of a field experiment where grass and legume species were grown in monocultures and the dry matter yield, rumen bag digestibility (RBDMD) and N content of leaf and stem components were monitored in the wet and dry seasons. Eight species of grass (Brachiaria decwnbens cv. Basilisk. Panicum maximum cv. Riversdale, Urochloa pullulans CPI 41192, Imperata cylindrica from Maiwa, South Sulawesi, Digitaria milanjiana CPI 41193, Cenchrus ciliaris cv. Malopo, Heteropogon contorlus and Setaria sphacelata cv. Splenda) were studied. P. maximum was the highest yielding grass in the wet season and B. decumbens in the dry season. The highest RBDMD in the whole plants were U. pulluians, P. maximum, S. sphacelata and D. milanjiana after 2 weeks regrowth in cycle I and S. sphacelata, B. decumbens, D. milanjiana and C. ciliaris in cycle 2. When total digestible DM was calculated for the whole of cycle I, P. maximum, B. decumbens and S. sphacelata were superior, but B. decumbens produced over twice as much as the other species in the dry season (cycle 2). The leaf N concentration of all grasses exceeded 1.0% (6.25% crude protein) in the regrowth in cycle I but did not exceed 0.5% in the dry season regrowth (cycle 2).