• Economic and Environmental Geology
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• v.11 no.3
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• pp.99-108
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• 1978

The Gum-Ho river basin is one of the densely populated area having more than 35% of the total population and it was also well irrigated since earlier days in the Nackdong river basin. Most of the easily developed source of surface water are fully utilized, and at this moment the basin is at the stage that no more :surface water can be made available under the present rapid development of economic condition. Since surface water supplies from the basin have become more difficult to obtain, the ground water resources must be thoroughly investigated and utilized greatly hereafter. In economic ground of the basin what part could ground water play? In what quantities and, for what uses could it be put? The answer to these questions can be relatively simple;the ground water resources in the basin can be put at almost any desired use and almost anywhere in the basin The area of the basin is at about $2088km^2$ in the middle part of Nackdong river basin and it is located along the Seoul-Pusan express highway. The mean annual rainfall is about 974.7mm, most of which falls from June to September during the monsoon. Accumulated is appeared approximately after every 8 year's accumlated dry period with the duration of 5 years. The water bearing formation in the basin include unconsolidated alluvial deposits in Age of Quaternary, saprolite derived from weathered crystalline rocks, Gyongsang sedimentary formations of the period from late Jurassic to Cretaceouse, and igneouse rocks ranging of the Age from Mesozoic to Cenozoic. The most productive ground water reservoir in the basin is calcareous shale and sandstones of Gyongsang system, which occupies about 66% of the total area. The results of aquifer test on Gyongsang sedimentary formation show that average pumping capacity of a well drilled into the formation with drilling diameter and average depth of $8{\frac{1}{2}}$ inch and 136m is $738m^3/day$ and also average specific capacity of those well is estimated $77.8m^3/D/M$. Total amount of the ground water reserved in the basin is approximately estimated at 37 billion metric tons, being equivalent 18 years total precipitations, among which 7 billion metric tons of portable ground water can be easily utilized in depth of 200 meters.

• Journal of Korean Society on Water Environment
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• v.34 no.5
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• pp.503-513
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• 2018

Freshwater cyanobacterial genus Dolichospermum is one of the most commonly spotted types of phytoplankton, whereas a limited number of studies on morphology of Dolichospermum spp. have been performed in South Korea. The purpose of this study is to investigate the succession pattern of cyanobacteria after weir construction, as well as morphological characteristics of Dolichospermum spp. from natural samples collected in the weir regions of Nakdong River. A total of 31 cyanobacterial taxa observed in this study were classified as belonging to 15 genera, 5 families, and 3 orders. Among them, morphological characteristics in the four species were classified into genus Dolichospermum, for most of the planktic former members of the genus Anabaena, were observed through light microscopy. Water bloom frequently occurred in the middle region of Nakdong River, the maximum number of cyanobacterial species appeared in the lower region of Nakdong River. The appearance of order Chrooccocales was only observed during summer when population density of Microcystis aeruginosa reached an annual peak. In contrast, filamentous cyanobacteria was observed throughout the whole year, even if when water temperature was lower than $5^{\circ}C$. It implied that the low-temperature-adapted filamentous cyanobacteria can grow in a range of water temperatures. Coil diameter of D. crassum from natural samples was $75{\sim}140{\mu}m$ ($ave.=91.3{\mu}m$; n = 94), slightly larger than those reported by previous studies. Dolichospemum smithii ($Kom{\grave{a}}rek$) Wacklin et al. 2009, was described for the first time in Nakdong River.

• Korean Journal of Medicinal Crop Science
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• v.18 no.1
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• pp.46-50
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• 2010

In order to development medicinal Artemisia herbs of high quality, Korean A. annua L. were investigated with its ecological and morphological characteristics, and basic statistical data of agronomic characteristics. This species, which is annual herb, is mainly distributed to marginal land, riverside, roadside, grassland. Ecological niche is low species in competition of the others. Its pollination is basically anemogamous, but is frequency pollinated by insects. This species is characterized as tap root, 1~3 pinnate compound leaf of ovate or narrowly ovate, stem is green, erect and solitary. Inflorescence is paniculate, receptacle is not hair. Capitulum, consist of ray floret and disk floret, is subglobose shape. Additionally, this species could be easily discriminated from related Artemisia herbs by the capitulum size. Ray floret is female, disk floret is bisexual. Flowering season is from August to October. Seed is achene unattached hair. Stem length ranged from 179 cm to 225 cm, and stem diameter and number of branch were $17.14\;{\pm}\;1.68\;mm$, $2.43\;{\pm}\;0.51\;mm$, respectively. Length and width of leaf were $14.5\;{\pm}\;0.5\;cm$, $15.0\;{\pm}\;1.0\;cm$, and leaf number of main stem were $48.06\;{\pm}\;10.57\;cm$, respectively. Fresh weight of aerial parts and root were $364.7\;{\pm}\;14.1\;g$, $32.6\;{\pm}\;5.1\;g$, and its dry weight were $136.6\;{\pm}\;10.0\;g$, $14.9\;{\pm}\;2.34\;g$, respectively.

• Environmental Analysis Health and Toxicology
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• v.13 no.1_2
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• pp.43-53
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• 1998

Ambient air levels of polycyclic aromatic hydrocarbons(PAHs) are of concern because of their potential for adverse health effects including transformation of some of these substances to mutagens and carcinogens by mammalian microsomal enzyme system. Airbone particulate samples were collected by a conventional high-volume sampler and by an Anderson cascade impactor on 2 to 3 days in each month over a period of 1 year at a representative site of the heavy traffic area of Seoul from beptember 1994 to August 1995. Ten individual PAHs in sizable air particulates of each stage of two months were separated and analyzed by gas chromatography/mass spectrometry. As a results of analysis, the gross concentrations of PAHs in the fine and coarse particles were higher in the winter month than in the spring, followed in descending order by in the fall and summer. In a study of dependency of 10 PAHs compounds on size distribution of particles at heavy traffic area found that about 85% of the total PAHs content was associated with particles less than 2.0um (fine particles) in diameter of winter sampling period. while 79% were associated with this size fraction during summer period. In according to the mean concentrations of the 10 PAHs in 7 size classification from < 0.38 to> 10.1, the 'size was the smaller, PAHs concentration was the higher. Thus it was found that PAHs concentration was greatly affected by air particle size. Annual mean benzo(a)pyrene equivalents was 5.88ng/m$^3$ and obtained by applying, toxic equivalency factor developed by Nisbet and Lagoy.

• The Korean Journal of Ecology
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• v.18 no.1
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• pp.189-201
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• 1995

In order to clarify regeneration processes and mechanisms of the disturbed Pinus densiflora forest, responses of Pinus densiflora to gap formed by disturbance were analysed by growth of saplings and mature and growth equations were obtained from branch growth of mature trees and height growth of saplings, and age distribution of saplings and young trees recruited within gap was analysed in relation to gap age. Height growth of saplings within gaps was accelerated after gap formation. Such abrupt increases of growth of saplings after the gap formation might be resulted in the difference of growth of saplings between gap and non-gap areas. In fact, height and diameter of saplings in the central part of gap were larger than those of saplings in marginal parts of gap and non-gap area. However, density of saplings was not different in both parts. In addition, growth of annual rings of mature trees bordering on gap also increased after gap formation. Branch growth of mature trees bodering on gap was 6.3 - 6.5 cm /year and the mean radius of gaps created by death of only one canopy tree was about 3 m. Therefore, for those gaps to be closed by branch growth it will take 46 years. Growth of saplings within gap showed exponential equation. Fifty years will be required for the saplings to enter the forest canopy by the exponential growth equation. Therefore, gap created by only one tree might be closed by branch growth of surrounding canopy trees in advance of being done by height growth of saplings. But gaps created by death of trees more than 2 will be closed by the growth of saplings. Among the regenerating saplings and young trees within gaps, individuals established in advance of gap formation were more than those established after the gap formation. From these results, it was assumed that the disturbed Pinus densiflora forests in these sites were regenerated by height growth of saplings recruited in advance of gap formation.

• Journal of Environmental Science International
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• v.16 no.10
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• pp.1157-1167
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• 2007

In an effort to interpret the characteristics of fine particle concentrations in Busan, time variations of hourly monitored concentrations $PM_{10}$ (Particulate Matter with aerodynamic Diameter ${\le}10\;{\mu}m$) in Busan are analyzed for the period from 2000 to 2005. The characteristics of aerosol second generation formation process is also interpreted qualitatively, by using the statistical analysis of the meteorological variables including temperature, wind speed, and relative humidity. The result shows some significant annual, seasonal, weekly and diurnal variations of $PM_{10}$ concentrations. In particular, seasonal(i.e., spring) variations are governed by frequency of yellow sand events even for the non-yellow sand cases where yellow-sand days are eliminated in our analysis. However, in seasonal variation, summer season predominate lower $PM_{10}$ concentrations due to the frequent precipitation, and weekly and diurnal variations are both found to be reflecting the emission rate from traffic amount. Correlation coefficients between $PM_{10}$ concentration and meterological variables for non-yellow sand days show overall negative correlation with visibility, wind speed, cloud amounts, and relative humidity. However for non-precipitation days, during non-yellow sand period positive correlation are found clearly with relative humidity, suggesting the importance of secondary aerosol formation in Busan that can be achieved by both homogeneous aerosol formation and heterogeneous transformations resulting from hygroscopic aerosol characteristics.

• Journal of Plant Biology
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• v.15 no.3
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• pp.1-8
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• 1972

A comparison between the productivity of the evergreen needle pine(Pinus densiflora) and of the deciduous broad leaved oak(Quercus mongolica) stands, which is located near Choon-Chun city, Kangwon dist. have been established. The pine stand had a stand density of 938 trees per ha and oak stand had of 638 trees per ha. The diameter at breast height (D) and the height of tree (H) of each tree were measured in sample plot of 800$m^2$. Twelve standard sample trees chose from the sample area felled down, and then weighed the stem, branches and leaves separately, according to both the stratified clip technique and the stem analysis. The vertical distribution of photosynthetic system was arranged effectively for high productivity in the productive structure of both trees. The allometric relation between D2H and dry weight of stem (Ws), branches (Wb) and leaves (Wl) of pine were approximated by log Ws=0.6212 log D2H-0.5383 log Wb=0.4681 log D2H-0.7236 log Wl=0.2582 log D2H-5.1567 and those of oak were approximated by log Ws=0.5125 log D2H＋0.0231 log Wb=0.5125 log D2H-0.3755 log Wl=0.8721 log D2H-2.9710 From the above, the standing crops of pine and oak in the sample area were estimated to be as much as 38.83ton and 48.11 ton of dry matter, above ground, per ha, respectively. Annual net production as the sum of the biomass newly formed during one year was appraised at 12.66ton/ha.yr in pine stand and at 8.74 ton/ha.yr in oak. The reason of high productivity of pine stand compared with oak might be resulted from much more about 4 times of the amount of the photosynthetic system, but less non-photosynthetic one of pine than those of oak. To increase the productivity of the forest stands investigated it was necessary to make densly a stand density, to be abundant in the inorganic nutrients and to preserve much water in soil to conserve the litters.

• The Korean Journal of Malacology
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• v.10 no.1
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• pp.38-48
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• 1994

Gonadal developmint, age and growth of Ruditapes philippinarum were investigated using samples from the intertidal zone of Simpo on the coast of Kimje, Korea, which were collected onthly for one year from Februaty 1993 to January 1994.Ruditapes philippinarum is diecious in sex. The gonads are located between the subregion of the midintestinal glands and reticular connective tissue of the foot. The ovary is composed of a number of ovarian sacs, and the testis is composed of numerous seminiferous tubules. The clam spawns once a year from early June to darly October, and the main spawning occurred between July and August when the water temperature went above 23$^{\circ}C$. Ripe oocytes are about 65-70${\mu}{\textrm}{m}$ in diameter. Gonadal phases of this species can be divided into five successive stages; multiplicative(February to March), growing (April to May), mature(Aprilto Septimber), spent(June to October), and degenerative and resting(july to March). Spawning is closely related to the sea water temperature. Based on the monthly variations of marginal index (MI')of the shell, it was suggested that the annual ring mark formation occurred in March once a year and took approximately 8 months (0.67 year) for first ring to be formed on the shell. The relationship between the shell length(SL) and the total weight (TW) was represented by nonlinear equation; TW=1.208 x 10/ sup -4/ S $L^{3.158}$, and also in the relationship be-tweenthe shell length (SL) and the shell height(SH), the shell length and the shell width (SW) were represented by the linear equations; SH=0.726 SL-0.483, SW=0.542 SL-0.803.Growth curves for shell length and total weight fitted to von Bertalanffs equation were expressed as: S $L_{t}$ =68.34(1- $e^{0.221}$(t+0.418)) T $W_{t}$ =75.16(1- $e^{0.221}$(t=0.418))$^{3.158/3.158}$

• KSBB Journal
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• v.21 no.1 s.96
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• pp.28-33
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• 2006

A sewage was treated using a horizontal flow zeolite-filled reed bed. The sewage from the student dormitory of Changwon National University was fed into the reed bed for 10 minutes every 6 hours at the hydraulic load of $314L/m^2$ day. The filtering height of the reed bed was 100 cm and the zeolite mixture was filled in the reed bed. The mixture consisted of the same volume of two types of zeolite : $0.5{\sim}1mm$ and $1{\sim}3mm$ in diameter. Annual average removal efficiency was SS $88.5%,\;COD_{cr},\;86.1%,\;COD_{Mn}\;81.0%,\;T-N\;48.6%,\;NH_4^+-N\;97.1%$ and T-P 42.8%. T-N of effluent was mostly $NO_3^--N$ and the concentration of $NO_2^--N$ in effluent was lower than 0.1 mg/L. All removal efficiencies did not show a remarkable seasonal change.

• Journal of Korean Society of Forest Science
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• v.62 no.1
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• pp.24-42
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• 1983

To develop Ilex cornuta which grow naturally in the southwest seaside district as new ornamental tree, the author chose I. cornuta growing in the four natural communities and those cultivated in Kwangju city as a sample, and investigated its ecology, morphology and characteristics. The results obtained was summarized as follows; 1) The natural distribution of I. cornuta marks $35^{\circ}$43'N and $126^{\circ}$44'E in the southwestern part of Korea and $33^{\circ}$20'N and $126^{\circ}$15'E in Jejoo island. This area has the following necessary conditions for Ilex cornuta: the annual average temperature is above $12^{\circ}C$, the coldness index below $-12.7^{\circ}C$, annual average relative humidity 75-80%, and the number of snow-covering days is 20-25 days, situated within 20km of from coastline and within, 100m above sea level and mainly at the foot of the mountain facing the southeast. 2) The vegetation in I. cornuta community can be divided that upper layer is composed of Pinus thunbergii and P. densiflora, middle layer of Eurya japonica var. montana, Ilex cornuta and Vaccinium bracteatum, and the ground vegetation is composed of Carex lanceolata and Arundinella hirta var. ciliare. The community has high species diversity which indicates it is at the stage of development. Although I. cornuta is a species of the southern type of temperate zone where coniferous tree or broad leaved, evergreen trees grow together, it occasionally grows in the subtropical zone. 3) Parent rock is gneiss or rhyolite etc., and soil is acidic (about pH 4.5-5.0) and the content of available phosphorus is low. 4) At maturity, the height growth averaged $10.48{\pm}0.23cm$ a year and the diameter growth 0.43 cm a year, and the annual ring was not clear. Mean leaf-number was 11.34. There are a significant positive correlation between twig-elongation and leaf-number. 5) One-year-old seedling grows up to 10.66 cm (max. 18.2 cm, min. 4.0 cm) in shoot-height, with its leaf number 12.1 (max. 18, min), its basal diameter 2.24 mm (max. 4.0 mm, min. 1.0 mm) and shows rhythmical growth in high temperature period. There were significant positive correlations between stalk-height and leaf-number, between stalk-height and basal-diameter, and between number and basal diameter. 6) The flowering time ranged from the end of April to the beginning of May, and the flower has tetra-merouscorella and corymb of yellowish green. It has a bisexual flower and dioecism with a sexual ratio 1:1. 7) The fruit, after fertilization, grows 0.87 cm long (0.61-1.31 cm) and 0.8 cm wide (0.62-1.05 cm) by the beginning of May. Fruits begin to turn red and continue to ripen until the end of October or the beginning of November and remain unfading until the end of following May. With the partial change in color of dark-brown at the beginning of the June fruits begin to fall, bur some remain even after three years. 8) The seed acquision ratio is 24.7% by weight, and the number of grains per fruit averages 3.9 and the seed weight per liter is 114.2 gram, while the average weight of 1,000 seeds is 24.56 grams. 9) Seeds after complete removal of sarcocarp, were buried under ground in a fixed temperature and humidity and they began to develop root in October, a year later and germinated in the next April. Under sunlight or drought, however, the dormant state may be continued.