• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
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• pp.262-265
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• 2004

The purpose of this study is to investigate environmental characteristics and in-situ hydraulic conductivity by eco cone penetration system. The underground environments and permeability of site was investigated and analyzed by this eco cone system. The electrical resistivity, pH, ORP, temperature and hydraulic conductivity were measured by eco cone penetration system. This eco cone penetration system provides a continuous environment and permeability profiles in underground, and provides reliable results for investigation of normal and contaminated ground.

• 한국환경농학회지
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• 제41권2호
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• pp.101-107
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• 2022

BACKGROUND: Soil amendment was necessary applied for the sand that had been used to root zone of green ground in golf course because of its low water retention power and cation exchangeable capacity. This study was conducted to evaluate the effect of the mixed ratio of peat moss and coconut coir as soil amendment materials on the soil physicochemical properties applied to rootzone based on sand. METHODS AND RESULTS: The soil amendments were blended at 0, 3, 5, 7 and 10% by soil volume. The pH in the peat moss treatment was lower than that of control (0% soil amendment), and pH and electrical conductivity (EC) in the coconut coir were higher. The blending ratio of peat moss was negatively correlated with pH of rootzone soil (p<0.01), and that of coconut coir positively with EC (p<0.01). As compared with control, capillary porosity, the physical factors such as air-filled porosity, total porosity, and hydraulic conductivity of rootzone soil were increased by applying peat moss and coconut coir. For correlation coefficients between percentage of soil amendments and soil physical factors, peat moss and coconut coir were positively correlated with porosity and hydraulic conductivity (p<0.01). CONCLUSION(S): These results indicated that the application of peat moss and coconut coir affected on the change of physicochemical properties of rootzone soil, and improved soil porosity and hydraulic conductivity.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2000년도 학술발표회 발표논문집
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• pp.54-65
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• 2000

This study was performed to analyze the changes of electrical conductivity with increasement of water requirements for desalinization in reclaimed tidelands and to obtain the basic data for developing prediction techniques of desalinization to be applicable in the beginning of tideland reclamation. Two different desalinization experiments were conducted through the leaching method by subsurface drainage and the rinsing method by surface darainage, using the samples of silt soil and silt loam soil collected in 5 units of tideland reclamation projects. Regression equations were obtained in order to investigate the changes of electrical conductivity during the desalinization of reclaimed tidelands and to estimate water requirements for desalinization.

• 한국농공학회지
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• 제31권1호
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• pp.96-105
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• 1989

This laboratory study was performed to produce basic data for the estimation of water requirements for desalinization, through analyzing changes of the electrical conductivity and the exchangeable sodium percentage during the desalinization of reclaimed tidelands. Desalinization experiments were carried out by two water management practices, namely, the leaching method by subsurface drainage and the rinsing method by surface drainage, using samples of silt loam soil and silty clay loam soil collected in reclaimed tidelands. The results obtained from this study were summarized as follows : 1. The sample soils used in this study were saline-sodic soils with the high electrical conductivity and the high exchangeable sodium percentage. 2. Changes of the electrical conductivity and the exchangeable sodium percentage with water requirements for desalinization showed a similar tendency in the desalinization experiment by the same water management practice. 3. The regression equation between the relative electrical conductivity(EC/EC) and water requirements for desalinization(Dw/Ds) could be described by Dw/Ds=O. 29x(EC/EC.) -0.982 (Leaching method), Dw/Ds=3. 678X0. 030(EC/EC ) (Rinsing method). 4. The regression equation between the relative exchangeable sodium percentage (ESP/ESP ) and water requirements for desalinization (Dw/Ds) could be expressed in Dw/Ds = 0.039 x (ESP/ESP. ) - 1. 134 (Leaching method), Dw/Ds=7. 197X0. 024(ESP/ESP ) (Rinsing method). 5. It was estimated that water requirements for the adequate desalinization would be Dw/Ds=0.3 (Leaching method) and Dw/Ds=3.0 (Rinsing method)

• Journal of Biosystems Engineering
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• 제39권1호
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• pp.39-46
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• 2014

Purpose: Monitoring and control of environmental condition is highly important for optimum control of the conditions, especially in greenhouses and plant factories, and the condition is not uniform within the facility. Objectives of the study were to investigate variability in soil water content and to provide information useful for better irrigation control. Methods: Experiments were conducted in a strawberry-growing greenhouse (greenhouse 1) and a cherry tomato-growing greenhouse (greenhouse 2) in winter. Soil water content, electrical conductivity (EC), and temperature were measured over the entire area, at different distances from an irrigation pump, and on ridge and furrow areas. Results: When measured over the entire greenhouse area, soil water content decreased and temperature and electrical conductivity increased over time from morning to afternoon after irrigation. Water content decreased by distance from the irrigation pump up to 70 m and increased after that, and temperature showed an inverse pattern. Soil water contents on the ridge were lower than those on the furrow, and the differences were 10.2~18.4%, indicating considerable variability. The lowest EC were observed on the furrow and highest values were observed on the ridge. Soil water contents were less and temperature levels were greater at the window side than in the center locations. Conclusions: Selection of number and location of soil water content sensor would be the first step for better water content monitoring and irrigation control. Results of the study would provide basic data useful for optimum sensor location and control for underground greenhouse environment.

• The Plant Pathology Journal
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• 제17권1호
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• pp.45-51
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• 2001

A root rot/vine decline disease occurred naturally on bottle gourd-stocked watermelon, melon, oriental melon and squash grown in greenhouses, but not on these plants grown in fields. Self-rooted watermelon, cucumber, pumpkin and luffa were also proven to be hosts of the pathogen by artificial inoculation in this experiment. The pathogen was identified as Monosporascus cannonballus by comparing microscopic characteristics of fungal structures with those of previously identified fungal strains. Our field investigations showed that the temperature and electric conductivity of soil in infected greenhouses were higher and the soil moisture content was lower than in noninfected greenhouses. To investigate soil-environmental factors affecting disease development, greenhouse trials and inoculation experiments were conducted. The host plants inoculated and grown under conditions of high soil temperature and electrical conductivity ($35\pm2^{\circ}$, 3.2-3.5 mS) and with low soil moisture content (pF 3.0-4.5) were most severely damaged by the fungal disease. Since plants growing in greenhouses ae usually exposed to such environmental conditions, this may be the reason why the monosporascus root rot/vine decline disease has occurred only on cucurbits cultivated in greenhouses but not in field conditions.

• 한국전자파학회논문지
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• 제20권4호
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• pp.406-412
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• 2009

본 연구에서는 주변 환경이 복잡하고 토양의 특성이 잘 알려지지 않은 지역에서는 적용이 가능한 중파대역 유효 대지 도전율 계산법을 제안하였다. 제안된 방법은 해안 기지국에서 측정된 전계 강도와 일반적인 중파대역 감쇠 모델을 이용하여 유효 대지 도전율을 계산하며, 오차를 최소화하기 위해 통계적인 방법을 이용하였다. 다음으로, 제안된 방법을 이용하여 국내의 중파대역 유효 대지 도전율을 얻었으며, 전계 강도 비교 및 오차 분석을 통해 제안된 방법의 정확도와 유용성을 확인하였다.

• Journal of Ecology and Environment
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• 제38권4호
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• pp.443-450
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• 2015

The east coast of the Korean Peninsula is susceptible to fires because of the low rainfall in winter and spring, and large forest fires have occurred in this area. Lack of fresh water to combat fires has hampered efforts to prevent widespread forest fires in this region. Seawater has not been used as a suppressant because of possible detrimental effects of salt. We investigated the mobility of saline water in the forest soil and their effect on the microbial activity. Using a fire-fighting helicopter, seawater was sprayed over three plots (50 × 100 m) located on the eastern slope of the Baekdu mountain range in South Korea in April, 2011. We sampled the soil in April 4, May 20, and August 5 to determine the amount of salt that remained in the soil. The electrical conductivity value of the soil decreased to <400 μS/cm over a 1-month period. Approximately, four months after the application of seawater, the electrical conductivity value and Na⁺ content in all treatment plots did not significantly differ to those of the control plot, and total microbial activity also recovered to that of the control. Our results indicate that the amount of rainfall, soil physical-chemical properties, and topological factors may be a critical factor determining the mobility of saline water in forest soil.

• 한국산림과학회지
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• 제88권4호
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• pp.498-509
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• 1999

이 연구는 전나무림과 잣나무림에서 산림시업(山林施業)(간벌 및 가지치기)이 산지의 물순환(循環) 소과정(素過程)에서 전기전도도에 미치는 영향인자(影響因子)를 파악하여 산림시업(山林施業)에 따른 산림(山林)의 수질정화기능(水質淨化機能)을 평가(評價)하기 위한 기초자료(基礎資料)를 제공(提供)하기 위하여 실시하였다. 1996년 3월부터 5월까지 산림시업을 한 광릉시험림 31, 33임반내 전나무림과 잣나무림 유역에서 1998년 3월 1일부터 동년 8월 4일까지 임분특성(林分特性), 강우(降雨), 임내우(林內雨)(수관통과우(樹冠通過雨), 수간류(樹幹流)), 토양수(土壤水), 계류수(溪流水)의 수질동태(水質動態)를 분석(分析)하였다. 산지의 물순환 소과정별로 분리했을 때 전나무림 시업구의 임내우, 토양수에서 전기전도도의 설명에 유의한 영향을 미치는 인자는 음(陰)이온총량(總量)과 $NO{_3}^-$이었고, 비시업구에서는 $SO{_4}^{2-}$, $Cl^-$, 음이온총량이었다. 잣나무림 시업구의 임내우 토양수에서 전기전도도의 설명(說明)에 유의(有意)한 영향(影響)을 미치는 인자(因子)는 $NO{_3}^-$와 선행무강우일수(先行無降雨日數)이었고, 비시업구에서는 이온총량(總量), $NO{_3}^-$, $K^+$, pH, 음이온총량이었다. 전나무림과 잣나무림 계류수에서 전기전도도의 설명에 유의한 영향을 미치는 인자는 강수량, $Na^+$, 이온총량이었다. 강우(降雨), 전나무림과 잣나무림에서 시업구(施業區)와 비시업구(非施業區)의 임내우(林內雨) 토양수(土壤水), 계류수(溪流水)를 통합했을 때 전기전도도(電氣傳導度)의 설명(說明)에 유의(有意)한 영향(影響)을 미치는 인자(因子)는 양(陽) 음(陰)이온총량(總量), $Na^+$, $Cl^-$, pH 등이었다.

• 한국토양비료학회지
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• 제29권4호
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• pp.396-402
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• 1996

식물생육촉진 유용미생물을 지리산 일대의 침엽수와 활엽수 밑의 부엽토(腐葉土)에서 선발하고, 고추에 접종하였을때 고추 묘소질과 생육 및 수량에 미치는 영향에 대한 결과를 요약하면 다음과 같다. 1. 혼합배양결과 Pseudomonas P배지는 $25^{\circ}C$에 Micrococcus sp., Enterobacter agglomerans, Pseudomonas putida, Pseudomonas fluorescens등 4균주, Sabouraud dextrose배지에서는 $35^{\circ}C$에서 Bacillus subtilis, Cellulomonas sp., Bacillus megaterium, Staphylococcus xylosus등 4균주의 생육이 양호하였다. 2. 혼합균주 처리구는 무처리구에 비해 초장, 분지수등은 증가하였고, EC 수준이 높아질수록 초장은 작아진 반면, 분지수는 혼합균주 처리 58일(日) 이후 EC 2.9ds/m에 비해 EC 8.6 dS/m에서 많아지는 경향이었다. 수량은 혼합균주 처리구가 무처리구에 비해 13% 증수되었고, EC 수준이 높아질수록 감소하는 경향이었다. 3. 시험후 토양의 EC, $P_2O_5$, K, Ca, Mg, $NO_3-N$은 EC 수준이 높아질수록 현저하게 증가하는 경향이었으며, 혼합균주 처리구는 무처리구에 비해 OM 및 $NH_4{^+}-N$은 낮은 반면, EC, $P_2O_5$, K, Ca, Mg, $NO_3-N$은 높은 경향이었다. 4. 시험후 혼합균주 처리구는 무처리구에 비해 수분율이 높은 경향이었으며, EC 수준이 높아 질수록 가밀도 수분율, 공극율 등은 증가하는 경향이었다. 5. 혼합균주 처리구는 무처리구에 비해 과실과 엽에서 T-N, $P_2O_5$, $K_2O$, CaO, MgO함량이 높았으며, EC 수준이 높아질수록 $P_2O_5$, $K_2O$, MgO 함량은 증가한 반면, CaO 함량은 낮아지는 경향이었다.