• Journal of the Korean Society of Groundwater Environment
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• v.5 no.3
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• pp.129-140
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• 1998

In this study two sites were selected to investigate groundwater contamination and spatial relationship between pollution level and its source. One is the Asan area, agricultural district where pollution sources are scattered. The other is the Gurogu area of Seoul city, industrial district where industrial complex and residential areas are located. Groundwater samples collected from these districts were analysis for chemical constituents. The attribute value files of the chemical constituents of groundwater and the spatial layers have been constructed and the pollution properties have been investigated to find out spatial relationships between the groundwater constituents and pollution sources using CIS. Relatively high contents of Si and HCO$_3$ in groundwater from the Asan area reflect the effect of water-rock interaction, whereas high contents of Cl, NO$_3$, SO$_4$and Ca in groundwater from the Gurogu area are due to the pollution of various sources. Pollution over the critical level of Korean Dinking Water Standard has been investigated from 15 sampling sites out of 40 in the Asan area, and 33 sampling sites out of 51 in the Gurogu area. There is pollution of NO$_3$, Cl, Fe, Mn, SO$_4$and Zn in groundwater from the Gurogu area, and that of NO$_3$, SO$_4$and Zn in groundwater from the Asan area. Principal pollution in both areas is NO$_3$contamination. Deep groundwater from the Asan area is not contaminated with NO$_3$except for one site and most of shallow groundwater near the potential point sources such as factory and stock farm is contaminated seriously. Groundwater from the Gurogu area has been already polluted seriously considering the fact of contamination of deep groundwater. This study reports a spatial relationship between the pollution level and pollution source using GIS.

• Journal of The Korean Society of Grassland and Forage Science
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• v.31 no.4
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• pp.395-408
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• 2011

The study which it sees exclusions the copper and the zinc which contain in pig sludge, It study pig sludge resources fertilizer production which are rational, pig sludge resources fertilizers after seeding, silage corn it investigates growth characteristics and forage value, the result which investigates pig sludge resources fertilizers effectiveness with afterwards is same. With fertilizer ingredients in pig sludge chemical qualities, the content of the nitrogen and the phosphoric acid comes 4.4% to be 6.29%, pH 7.02 and content of the copper and the zinc which is a heavy metal which contains in pig sludge with 805 mg/kg and 1,704 mg/kg, it is a restrictive standard of the fertilizer, 300 mg/kg and 900 mg/kg it sees to be high, it manufactures citric acid 1 hydrate with the organic acid solution, heavy metals of pig sludge where it is a mixture ratio of the organic acid solution, it divides to 25%, 50%, 75% and 100% 4 kind levels, the result which measures the heavy metal exclusion ratio of the copper and the zinc, the mixture ratio of the organic acid solution to be many exclusion ratio of the copper and the zinc is showing a just interrelation, from organic acid solution 100% level content of pig sludge remains copper and zinc 330.03 mg/kg and 41.28 mg/kg, it shows the exclusion ratio of copper 59% zinc 97%. 'Cheonganok' growth characteristics with citric acid 1 hydrate, Treatment 2 and control growth characteristics etc, it exclusion the copper and the zinc it doesn't appear on significant difference statistically but, treatment 3 after only pig sludge in resources disposal where it seeding, growth characteristics of leaf area etc. is badness, it compares in control and treatment 2 the growth characteristics badness, it is appearing, it is caused by with disease and insects occurrence of $Ostrinia$ $furnacalis$ and brown spot, the damage was many. From forage value, Treatment 2 where it exclusion the heavy metal with the citric acid 1 hydrate with control it compares and there are not significant difference from crude protein and ADF and NDF contents etc., seeding only Pig Sludge in resources disposal treatment 3, it is caused by with $Ostrinia$ $furnacalis$ etc., trunk and aging of the leaf to be high ADF content is low. but from crude protein, the nitrogen ingredient which pig sludge has and interrelation it seemed and high numerical value were confirmed.

• Korean Journal of Environmental Agriculture
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• v.30 no.2
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• pp.132-137
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• 2011

BACKGROUND: This experiment was carried out to evaluate the effect of potassium fertigation on the growth and yield of fourteen years-old 'Campbell Early' grapevine (Vitis labrusca L.) on a sandy loam soil. METHODS AND RESULTS: Potassium application (125 kg/ha/yr) was top-dressed as 30% of annual potassium application in all treatments and the remainders were drip-irrigated with 0 (0% of total K, K0 level of the remainder), 25 (17.5% of total K, K1/4 level of the remainder), 50 (35% of total K, K1/2 level), and 100mg/L (70% of total K, K1 level) in the intervals of 2 times a week for 12 weeks and the effect of K drip fertigation was compared to control treatment in which the K remainder was applied with surface application as additional fertilizer. The growth of stem diameter, leaf number and shoot length were highest in K1/2 (50 mg/L K), but K of mineral contents was lowest in K0. Yield of grapevine was no difference in 2008, but significantly higher K1/2 than other treatments in 2009. However, fruit quality (color degree, brix, acid contents) was no difference among the treatment. CONCLUSION(s): From the results, It is expected that K1/2 levels of fertigation based on soil testing could be more efficient to get optimum yield and save potassium fertilizer than control (surface application) treatments when grapevine was drip-irrigated at open field condition.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.2
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• pp.127-138
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• 2000

To enable rapid and convenient soil test, new soil analytical methods, which require only one instrument, UV/Vis spectrophotometer, were developed and named "Soiltek KA-P spectrophotometric methods". The Soiltek$^{(R)}$ KA-P spectrophotometric method was compared with standard method of RDA in analytical capability for soil chemical properties. Using the 78 soils collected from upland, paddy, orchard, and vinyl house soils, soil organic matter, exchangeable K, Ca, and Mg. CEC, available $SiO_2$, and nitrate were analyzed by the two methods. The color stability(ratio of the absorbance at elapsed time t to the absorbance at time t=0) of organic matter. Ca, Mg, and available $SiO_2$ decreased to about 2% within one hour. However, that of exchangeable K, CEC, and nitrate remained constant. The results obtained with Soiltek$^{(R)}$ KA-P spectrophotometric method showed highly significant correlation with those measured by the standard method of RDA($R^2$ >0.9501), in which the slopes were near unity of $1.0{\pm}0.05$. The standard deviation values of organic matter, exchangeable K, Ca, and Mg, CEC, available $SiO_2$, and nitrate were apparently lower than ${\pm}1.8gkg^{-1}$, ${\pm}0.05cmol^+kg^{-1}$, ${\pm}0.18cmol^+kg^{-1}$, and ${\pm}0.13cmol^+kg^{-1}$, ${\pm}1.0cmol^+kg^{-1}$, ${\pm}5.0mgkg^{-1}$, and ${\pm}10.0mgkg^{-1}$, respectively. All the measurements showed coefficients of variation of less than 7~17% and were within the confidence level of 95%, which means both the methods are precise. Considering the relative simplicity, low cost, precision and accuracy, the proposed Soiltek$^{(R)}$ KA-P spectrophotometric methods could be recommended as an alternative to standard method.

• Journal of Soil and Groundwater Environment
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• v.13 no.1
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• pp.1-12
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• 2008

The purpose of this study is to characterize the hydrogeochemical characteristics of hot spring waters and to interpret the source of noble gases and the geochemical environment of the hot spring waters distributed along the eastern area of the Korean peninsula. For this purpose, We carried out the chemical, stable isotopic and noble gas isotopic analyses for eleven hot spring water and fourteen hot spring gas samples collected from six hot spring sites. The hot spring waters except the Osaek hot spring water show the pH range of 7.0 to 9.1. However, the Osaek $CO_2$-rich hot spring water shows a weak acid of pH 5.7. The temperature of hot spring waters in the study area ranges from $25.7^{\circ}C$ to $68.3^{\circ}C$. Electrical conductivity of hot spring waters varies widely from 202 to $7,130{\mu}S/cm$. High electrical conductivity (av., $3,890{\mu}S/sm$) by high Na and Cl contents of the Haeundae and the Dongrae hot spring waters indicates that the hot spring waters were mixed with seawater in the subsurface thermal system. The type of hot springs in the viewpoint of dissolved components can be grouped into three types: (1) alkaline Na-$HCO_3$ type including sulfur gas of the Osaek, Baekam, Dukgu and Chuksan hot springs, and (2) saline Na-Cl type of the Haeundae and Dongrae hot springs, and (3) weak acid $CO_2$-rich Na-$HCO_3$ type of Osaek hot spring. Tritium ratios of the Haeundae and the Dongrae hot springs indicate different residence time in their aquifers of older water of $0.0{\sim}0.3$ TU and younger water of $5.9{\sim}8.8$ TU. The ${\delta}^{18}O$ and ${\delta}D$ values of hot spring waters indicate that they originate from the meteoric water, and that the values also reflect a latitude effect according to their locations. $^3He/^4He$ ratios of the hot spring waters except Osaek $CO_2$-rich hot spring water range from $0.1{\times}10^{-6}$ to $1.1{\times}10^{-6}$ which are plotted above the mixing line between air and crustal components. It means that the He gas in hot spring waters was originated mainly from atmosphere and crust sources, and partly from mantle sources. The Osaek $CO_2$-rich hot spring water shows $3.3{\times}10^{-6}$ in $^3He/^4He$ ratio that is 2.4 times higher than those of atmosphere. It provides clearly a helium source from the deep mantle. $^{40}Ar/^{36}Ar$ ratios of hot spring water are in the range of an atmosphere source.

• Korean Journal of Ecology and Environment
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• v.37 no.2 s.107
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• pp.248-254
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• 2004

This study was conducted to investigate the effects of salinity in irrigation water on the growth, yield components, yield and grain quality of rice plant by the pot experiments. Irrigation waters were supplied with control and amended with NaCl at 1,000, 2,000, 3,000, 5,000, and 7,000 ${\mu}s\;cm^{-1}$ electrical conductivity. A randomized block design was used with four replicates for each treatment and control. As increasing salt concentration, plant height, tiller number, SPAD value, dry weight, content of N, P, and K, ripened grain ratio (%), 1,000 grain weight, and protein content (%) tended to decrease, especially, significant at 3,000 ${\mu}s\;cm^{-1}$ of salt level. Grain yield decreased significantly at all treatments. The percentage of head rice slightly tended to increase as the salt concentration due to the decrease of green kernel. The percentage of green kernel was significantly lower at 3,000 ${\mu}s\;cm^{-1}$ of salt level than the control.

• The Korean Journal of Pesticide Science
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• v.5 no.2
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• pp.45-50
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• 2001

In recent, non virus-induced mosaic symptoms(NVMS) on potato leaves were observed in the seed potato fields, and its incidence rate was $5{\sim}20%$ nationwide. It made difficult to rogue out virus-infected plants, and caused much arguments between seed potato production farmers and seed potato inspectors. The objectives of these experiments were to find out the causes of NVMS, and also to induce mosaic symptom(phytotoxicity) on potato plants by treatment of several herbicides. No significant correlations were found between incidence rates of NVMS and values from soil analyses; soil pH, soil EC, organic matter content, and contents of inorganic constituents($P_2O_5,\;NO_3$, Ca, Mg, K) in the soil around the potato planted. The examinations by ELISA, virus indicator plants, and TEM showed that NVMS on potato leaves was not caused by the viruses infection. But, the use of herbicides could induced the NVMS on potato leaves. The incidence rates of potato treated with pendimethalin linuron of 400 mL/10 a, pendimethalin of 200 mL/10 a, pendimethalin.oxadiazon of 300 mL/10 a, and control were 61.1%, 47.2%, 19.4%, and 1.4%, respectively. Based on these results, we confirmed that the treatment of pendimethalin alone and in mixture with other herbicides were the reason of NVMS on potato leaves. The yields among test plots were similar except dicamba treated plot, which decreased by about 23% compared to control plot. When their progenies harvested in 1999 were planted in the following season, no symptoms of mosaic were observed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.15 no.3
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• pp.175-185
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• 1995

This experiment was carried out to investigate the optimum rates of animal excreta(cattle slurry-N) for the highest dry matter production and improve the nutritive values of reed canarygrass with different cutting frequency. The results are summarized as follows; The highest relative dry matter yields for annual dry matter yield were 42.2% and 45.2% at 3rd cut in 3 and 4 cuttings, and 34.7% at 4th cut in 5 cuttings, respectively. The annual dry matter yields of non slurry-N application plot showed were from 6.8 tons to 8.0 tons/ha in all cutting frequencies. The highest annual dry matter yield obtained was in 3 cuttings. The annual dry matter yield increased with an increase of applied rates of slurry-N in all cutting frequencies. Annual dry matter yield was produced by 3.3 tons/ha at rates of 90 kg N/ha/cut in 3 cuttings, and more 1.7 tonsha and 2.4 tons/ha at rates of 30 kg N/ha/cut in 4 and 5 cuttings than that of non slurry-N application plots. The contents of crude protein were 12.01% and 15.0% at rates of 90 kg N/ha/cut in 3 and 4 cuttings, and 16.59% at rates of 120 kg N/ha/cut in 5 cuttings, respectively. On the contrary, the content of acid detergent fibre(ADF) showed the lowest values at same rates of slurry-N application in each cutting. J. The average content of crude protein was significantly increased with cutting frequencies, and they were 11.43%, 13.53% and 15.53% in 3, 4 and 5 cuttings, respectively. The average contents of acid detergent fibre(ADF) were 40.27%, 40.53% and 37.06% in 3, 4 and 5 cuttings. The values of 5 cuttings were significantly lower than other cutting frequencies, but the values of acid detergent fibre(ADF) was not significantly different between 3 and 4 cuttings. 6. The efficiency of dry matter production to slurry-N application rates showed the highest values of 18.9 kg and 15.7 kg DM/kg N at rates of 30 kg N/ha/cut in 3 and 5 cuttings, and 16.3 kg DM/kg/ N at rates of 90 kg N/ ha/cut in 4 cuttings. The efficiency of total nitrogen yield to slurry-N application rates were the highest values of 0.51 kg and 0.43 kg W k g N at rates of 30 kg N/ha/cut in 4 and 5 cuttings, and 0.52 kg TN/kg N at rates of 90 kg N/ha/cut in 3 cuttings, respectively. 7. The ranges of economic slurry-N rates were estimated as the 107.2-151.0 kglha, 359.1-375.7 kgha and 160.3-236.9 kg/ha in 3, 4 and 5 cuttings, and marginal dry matter yields were 9.6-10.0 tons/ha, 12.4-12.6 tons/ha and 9.0-9.7 tons/ha in 3, 4 and 5 cuttings, respectively. 8. The limiting sluny-N application rates to maintain the highest dry matter yields were estimated to be 420.0 kg/ ha, 440.6 kg/ha and 666.3 kg/ha in 3, 4 and 5 cuttings.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.4
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• pp.183-189
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• 2000

This study was carried out to analyze ecophysiological responses for seedling of Quercus serrata, Quercus mongolica and Quercus variabilis that are the typical species of deciduous broadleaved forests in Korea. And executed experiments in the climatic control room to provide necessary information to ecological forest management and methods of natural regeneration through the analysis of seedling responses. The details of experimental analysis were growth processes of 4 months after seeding that vary with the condition of three light intensity[relative light intensity(RLI) 8%, 20%, 52%] and three soil moisture[water suction(WS) Ψ=100 hPa, Ψ=280 hPa, Ψ=330 hPa] gradient, growth factors after harvesting and the nutrition condition of leaves. The results of this study are followings: 1) Early growth was prosperous after germination for the species which have more weight of acorn. 2) The formation of lammas shoot was favourable with Q. variabilis and Q. mongolica. And the rate of the occurrence was the highest in the RLI 20%, and it was remarkably reduced in the RLI 8%. 3) As the height growth of seedling of all 3 species were greater in the RLI 20% and 8% than that of the RLI 52%, they showed strong shade tolerance. 4) The increase of light intensity promoted the diameter at root collar growth, and development of main and lateral roots with all 3 species. 5) It showed that the increase of light intensity in the experimental radiation condition raised special leaf area weight(mg/cm$^2$) and leaf area productivity(mg/cm$^2$). Consequently, these resulted in the increase of leaf thickness and total dry biomass per the unit area of leaf. 6) As the increase of light intensity, the minerals contents of leaves such as N, P and K were lowered, and the increase of soil moisture resulted in the increase of P, K, Ca and Mg.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.3
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• pp.400-407
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• 2011

To evaluate the aquatic ecological characteristics in Sinpyongcheon constructed wetlands for treating nonpoint source pollution, the removal rates of nutrients in water, the total amounts of T-N and T-P uptakes by water plants, and chemical characteristics of T-N and T-P in sediment were investigated. The concentrations of BOD, COD, SS, T-N and T-P in inflow were 0.07~1.47, 0.60~2.65, 0.50~4.60, 1.38~6.26 and $0.08{\sim}0.32mg\;L^{-1}$, respectively. The removal rates of BOD, COD, SS, T-N, and T-P were 14%, 6%, 18%, 24%, and 10%, respectively. The maximum amount of T-N uptake by water plants in August was $813mg\;plant^{-1}$ for Phragmites communis TRIV in $2^{nd}$ bed, $1,172mg\;plant^{-1}$ for Typha orientalis PRESL in $3^{rd}$ bed, respectively. The maximum amount of T-P uptake by water plants in August was $247mg\;plant^{-1}$ for Phragmites communis TRIV in $2^{nd}$ bed, $359mg\;plant^{-1}$ for Typha orientalis PRESL in $3^{rd}$ bed, respectively. Organic matter, T-N, and T-P contents in sediments were high in the order of $1^{st}$ bed > $2^{nd}$ bed > $3^{rd}$ bed. Microbial biomass C/N/P ratios in sediments in $1^{st}$, $2^{nd}$, and $3^{rd}$ were 78~110/3~6/1, 73~204/1~6/1, and 106~169/1~6/1, respectively.