• Journal of Soil and Groundwater Environment
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• v.14 no.4
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• pp.23-32
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• 2009

The sorption of europium (Eu (III)) onto kaolinite and the influence of humic acids over a range of pH 3 ~ 11 has been studied by batch adsorption experiment (V/m = 250 : 1 mL/g, $C_{Eu(III)}\;=\;1\;{\times}\;10^{-5}\;mol/L$, $C_{HA}\;=\;5{\sim}50\;mg/L$, $P_{CO2}=10^{-3.5}\;atm$). The concentrations of HA and Eu(III) in aqueous phase were measured by UV absorbance at 254nm (e.g., $UV_{254}$) and ICP-MS after microwave digestion for HA removals, respectively. Results showed that the HA sorption onto kaolinite was decreased with increasing pH and their sorption isotherms fit well with the Langmuir adsorption model (except pH 3). Maximum amount ($q_{max}$) for the HA sorption at pH 4 to 11 was ranged from 4.73 to 0.47 mg/g. Europium adsorption onto the kaolinite in the absence of HA was typical, showing an increases with pH and a distinct adsorption edge at pH 3 to 5. However in the presence of HA, Eu adsorption to kaolinite was significantly affected. HA was shown to enhance Eu adsorption in the acidic pH range (pH 3 ~ 4) due to the formation of additional binding sites for Eu coming from HA adsorbed onto kaolinite surface, but reduce Eu adsorption in the intermediate and high pH above 6 due to the formation of aqueous Eu-HA complexes. The results on the ternary interaction of kaolinte-Eu-HA are compared with those on the binary system of kaolinite-HA and kaolinite-Eu and adsorption mechanism with pH was discussed.

• Korean Journal of Soil Science and Fertilizer
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• v.9 no.1
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• pp.47-55
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• 1976

This study is conducted to find out potential evapotranspiration values computed by a reasonable formula which is well suited among the existing ones for Suweon area. Each formula based on the data from Suweon Agricultural Meteorological Station during 1964 to 1973. Five formulas which are Blanney-Criddle, Thornthwaite, Penman, Jensen-Haise and Truc have been applied for calculation of potential evapotanspiration. Results obtained are summarized as follows. 1. Potential evapotranspiration of Suweon area shows uni-modal distribution which maximum value occurs in summer and minimum value occurs in winter. Annual potential evapotranspiration computed by Blanney-Criddle formula is 1,377 mm and that computed by others ranges from 714mm to 896mm. 2. Potential evapotranspiration computed by Blanney-Criddle formula is higher value than that computed by others, and among the other formulas it's values show little differences. However, relationships between the former and the mean of four others is highly correlated. 3. In comparison with potential evapotranspiration computed by formulas and actual evapotranspiration for rice paddy which is already reported, value for crop coefficient may be 0.8 in local varities, 1.0 in Tongil varity on Blanney-Criddle formula, and 1.2 in local varities and 1.5 in Tongil varity on the mean of four other fomulas. 4. Five formulas may applied for calculation of potential evapotranspiration because of relatively good correlation among them. However Blanney-Criddle formula is one of recommendable ones, because it is easy to compute and requires less data in compare with other formulas.

• Korean Journal of Soil Science and Fertilizer
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• v.22 no.4
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• pp.301-306
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• 1989

For the agricultural utilization of Korean forest land resources, which constitutes most of country, the distribution of environment and soil physico-chemical properties of establishable grass lands were clarified. The surveyed data were analized for the reasonable utilization and management of establishable grass land. The results were as follows ; 1. About 50.2% of the grass lands to be established were located under the 200m in altitude. The higher the altitude was, the more the organic matter content. 2. Tall type grass species such as Miscanthus purpurascens, Purple eulalia, and Themeda Japonica covered 71.3% of the natural vegetation in the soils of grass land to be established. 3. The extent of sandy and clayey soils which might be limited in the establishment of grassland was only 3.3%, meanwhile majority of the soils were in the favourable condition for grassland that is about 94% have more than 20cm in available soil depth and about 60.5% of the soils have less than 10% of gravels and stones in the soil profiles. 4. The chemical properties of the prearranged grassland soils were worse than the established grasslands, especially in the content of available $P_2O_5$. 5. The amount of fertilizer recommended for meadow were 286kg of nitrogen per hectare, 271kg of phosphorus, 224kg of potassium and 2040kg of calcium per hectare, but for grazing land were 201, 204, 136 and 1920kg/ha respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.34 no.1
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• pp.33-41
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• 2001

Enormous volumes of mining wastes from the abandoned and closed mines are disposed without a proper treatment in the upper Okdong River basin at Southeastern part of Kangwon Province. Erosion of these wastes contaminates soil, surface water, and sediments with heavy metals. Objectives of this research were to fractionate heavy metals in the mine tailing stored in the Sangdong Tungsten tailing dams and to assess the potential pollution index of each metal fraction. Tailing samples were collected from tailing dams at different depth and analyzed for physical and chemical properties. pH of tailings ranged from 7.3 to 7.9. Contents of total N and organic matter were in the ranges of 3.2~5.5%, and 1.3~9.1%, respectively. Heavy metals in the tailings were higher in the newly constructed tailing dam than those in the old dam. Total concentrations of metals in the tailings were in the orders of Zn > Cu > Pb > Ni > Cd, exceeded the corrective action level of the Soil Environment Conservation Law and higher than the natural abundance levels reported from uncontaminated soils. Relative distribution of heavy metal fractions was residual > organic > reducible > carbonate > adsorbed, reversing the degree of metal bioavailability. Mobile fractions of metals were relatively small compared to the total concentrations. Distribution of metals in the tailing dam profiles was metal specific. Concentrations of Cu at the surface of tailing dams were higher than those at the bottom. Pollution index (PI) values of each fraction of metals were ranged from 4.27 to 8.51 based on total concentrations. PI values of mobile fractions were lower than those of immobile fractions. Results on metal fractions and PI values of the tailing samples indicate that tailing samples were contaminated with heavy metals and had potential to cause a detrimental effects on soil and water environment in the lower part of the stream. A prompt countermeasure to prevent surface of tailings in the dams from water and wind erosions is urgently needed.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.3
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• pp.139-144
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• 2000

This study was conducted to obtain the basic information to increase the practical use of soil survey data through the subdividing of valley shapes with soil sequences due to different parent rocks, and to study the relationship between the valley shapes and parent rock. The various rocks such as sedimentary(gray shale and sand stone) and igneous rocks(granite, granite gneiss and andesite porphyry) which are the major parent rocks in Yeongnam area were investigated. The characteristics of valleys formed and the kinds of soils derived from different rocks were analysed by using aerial photographs and topographical maps scaled 1:5,000. The rill density in igneous rock area was as high as 40. But the rill bifurcation ratio of first order stream was higher in the sedimentary than the igneous rocks except granite area. The mean slope of valleys in igneous areas was about 8%, which was higher than that of the sedimentary areas. The variability of valley width in the complexly metamorphosed rock, such as granite gneiss, and andesite porphyry, was greater than in sedimentary and in granite rocks. Based on the variability of valley widths and valley slopes, it was possible to classify the valleys into two types. The "Uterus-shaped valleys" had wide variability of valley width and were located in the areas of granite gneiss and andesite porphry rocks. while the "Roots-shaped valleys" had narrow variability of valley width and were located in the sedimentary areas. "Uterus-shaped valleys" were typified by having land forms of mountain foot slopes and alluvial fans, and the soil drainage sequences also had complexities. So that, we concluded that the variability of valley width and valley slopes was associated with kinds of parent rocks and metamorphism which influences soil sequence and characteristics.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.3
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• pp.193-204
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• 2000

In order to get some basic data on environmental friendly function by Korean organic farming, the chemical characteristics of soil were determined on 100 farm cultivating site in Paldang watershed area of Great Seoul. The EC and content of $NO_3-N$ and Av. $P_2O_5$ in topsoil(0~30cm) showed $2.30dS\;m^{-1}$, $82mg\;kg^{-1}$, $918mg\;kg^{-1}$ in the soil cultivated chinese cabbage. $2.29dS\;m^{-1}$, $86mg\;kg^{-1}$, $954mg\;kg^{-1}$ in the soil of lettuce, $1.83dS\;m^{-1}$, $66mg\;kg^{-1}$, $1114mg\;kg^{-1}$ in the soil of crown daisy. These salt accumulation(EC) and the high concentration of mineral content in topsoil such as nitrate and phosphate showed the soils of organic farming were contaminated by practice of organic farming for the maintenance strategy of soil fertility. The $NO_3-N$ and Av. $P_2O_5$ in the subsoil(30~60cm) showed $75mg\;kg^{-1}$ and $641mg\;kg^{-1}$, $72mg\;kg^{-1}$ and $466mg\;kg^{-1}$, $42mg\;kg^{-1}$ and $873mg\;kg^{-1}$ in soil cultivated chinese cabbage, lettuce and crown daisy respectively. It indicates eventually the high concentration of nitrate and phosphate in topsoil caused penetration to subsoil, and the high concentration of mineral contents in subsoil indicate the potential risk of leaching of ground water by Korean organic farming. The positive correlation at 1% between EC and $NO_3-N$, $K_2O$, T-C, $P_2O_5$ and T-N show the salt accumulation in the both soil depth of Korean organic farming were caused by minerals such as $NO_3-N$, $K_2O$, T-C, $P_2O_5$ and T-N by overuse of organic fertilizer.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.1
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• pp.25-32
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• 1998

To characterize the growth environment, inorganic composition and morphological chracteristics of leaves of Korean tea plant, soil and tea leaf samples were collected from 15 locations and analyzed. The chemical characteristics of soils were in range of pH 4.09~6.15, OM 23.9~72.6g/kg, available phosphate less than 300mg/kg, K $0.8{\sim}2.5cmol^+/kg$, Na $tr{\sim}0.17cmol^+/kg$, Ca $1.0{\sim}6.2cmol^+/kg$, and Mg $0.3{\sim}2.1cmol^+/kg$. The contents of Ni. Cr, Zn. Cu, Pb, and Cd were at the level less than natural content in upland soil. Most of the sample soils were sandy loamy and loamy texture. The native tea plants were mainly grown in bamboo thicket or in forest. The leaf sizes of tea plants were $6.85{\pm}1.75{\times}2.6{\pm}0.5cm$, lateral vein number $14.2{\pm}2.7$, and crenated number $58.5{\pm}11.2$, and the leaf color was thin to dark green. The contents of $NH_4{^+}$, $Na^+$, $K^+$, $Mg^{2+}$ and $Ca^{2+}$ in tea leaves were in range of 30.5~47.7, 45.5~164.5, 16,998~25,431, 1.590~2,392 and 1,085~1,958mg/kg, respectively. The contents of $F^-$, $Cl^-$, $NO_3{^-}$, $PO_4{^{3-}}$ and $SO_4{^{2-}}$ were in range of 21.2~63.2, 126.4~257.9, 108.5~185.9, 1,270~1.819, and $954{\sim}1,670mg/kg$, respectively. The leaf size of native tea plant grown widlly in Shunchun Changchun-ri, Hwasun Ssangbongsa, Kuryoi Chonunsa, Bosong Daewonsa and Namhae Boriam was as large as those of Yabukita. Japan cultiver, grown at Kangjin Jangwon tea field.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.351-356
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• 2006

A long-term experiment was initiated in 1979 at Experiment Farm of Honam Agricultural Research Institute, to investigate the effects of continued use of organic matter (rice straw and compost) along with different levels of nitrogen fertilizer in rice cultivation. The soils of experimental plots is classified as Jeonbug series developed on Fluvio-marine deposits. The application rates of rice straw and compost were 5 Mg/ha/year and 10 Mg/ha/per year, respectively. The fertilizer N application rates per season were 0, 100, 150, 200, and 250 kg/ha. In 2002, after 24 years of experiment, the effect of different treatments on soil pH, characteristics soil organic matter, soil N and P were investigated. The results of the study is summarized as following. The continue use of organic matter tended to lower the soil pH, to increase organic matter and available phosphate contents. The rice straw tended to lower soil pH more than compost, while the effect of compost was greater in increasing soil organic matter and available soil P then rice straw. The application of organic matter resulted in the increase in total organic N in the soil. Such effect was greater in compost application than in rice straw application. In organic N, greatest was amino acid-N, followed by unidentifiable organic N. The least was amino sugar-N. The application of organic matter with and without nitrogen fertilizer affected the in organic fractions of P, particularly Fe-P and Al-P. The application of rice straw tended to increase Ca-P.

• Korean Journal of Soil Science and Fertilizer
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• v.39 no.6
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• pp.339-344
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• 2006

A lot of organic wastes have been produced from diverse industries, they must be tested by the regulation of fertilizer control act if reuse the organic wastes for agricultural utilization. The regulation has had only two criteria; the content of organic matter and 8 heavy metals. This study was conducted to evaluation trace element (boron, cobalt, molybdenum, and selenium) and distribution of organic compounds with different classification for complement the regulation in 16 organic waste materials(62 samples) collected from different regions and industries. Contents of boron(leather industry sludge, $154.2mg\;kg^{-1}$; food company sludge, $57.1mg\;kg^{-1}$), cobalt(industrial area sewage sludge, $95.2mg\;kg^{-1}$; metropolitan sewage sludge, $22.9mg\;kg^{-1}$), molybdenum(metropolitan sewage sludge, $40.1mg\;kg^{-1}$; food company sludge, $16.8mg\;kg^{-1}$), selenium (fiber industry sludge, $28.1mg\;kg^{-1}$; leather industry sludge, $16.9mg\;kg^{-1}$; food company sludge, $15.9mg\;kg^{-1}$) were highest compare to the other organic wastes. Total PAHs contents were the highest in paper-mill manufacture($3,462ug\;kg^{-1}$), and among the 16 PAHs, naphthalene, phenanthrene, pyrene, fluoroanthene, Anthracene and acenaphthene were detected more clearly than others in all kinds of organic resources.

• Korean Journal of Soil Science and Fertilizer
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• v.28 no.2
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• pp.154-159
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• 1995

In order to find out the effects of shading and nitrogen fertilizer on $NO_3^-$ accumulation in the edible parts of chinese cabbage, Cutivar, "Seoul", was cultivated in the pots under glasshouse condition with different rates of shading(0, 15, 30, 50, 75%) and nitrogen fertilization(recommended level, and double rate of recommended level). Leaf length, leaf width, yield (leaf weight), root width and root weight in the 15% shading rate showed the highest value, but decreased in the over 30% shading rates. The highest yield showed in the plot of the 15% shading rate with double rate application of recommended N level. High rate of shading increased the $NO_3^-$ accumulation, especially in midrib and outer leaf compared to leaf blade and inner leaf, respectively. The average $NO_3^-$ accumulation of edible parts of chinese cabbage are $4,872mg\;kg^{-1}$(outer midrib), $2,363mg\;kg^{-1}$(inner midrib), $1,405mg\;kg^{-1}$(outer leaf blade) and $727mg\;kg^{-1}$(inner leaf blade). $NO_3^-$ accumulation of outer midrib in the plots of double application of recommended N level were no difference between shading rate containing $5,000{\sim}6,000mg\;kg^{-1}$ $NO_3^-$, while in the plots of recommended N level it was increased by elevating shading rate. It was concluded that overuse of nitrogen fertiliration for chinese cabbage in glasshouse condition might lead to increase $NO_3^-$ accumulation. It could be advisable to cut out both the out leaf blade and outer midrib which might accumulate the high concentration of $NO_3^-$ before consumption.