• Journal of Plant Biology
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• 제16권3_4호
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• pp.1-6
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• 1973

The distribution of plant communities along the Bukhan Riverside in Chun-seong was studied by means of the methods fo Curtis and Pattern. The communities were arranged in a single-dimensioned ordination on the basis of the importance values of the persistent species. Leading dominant species, form the 'low' level to the 'high' levels of the ordination gradient, were Phalaris arundinacea, Salix gilgiana, Artemisia feddei, Zoysia japonica, Pennisetum japonicum, and Arundinella hirta. These species from a continuum from the river to the dry grassland depending upon available soil-moisture. Standing crops in terms of dry weight and the nitrogen content of the above-ground parts of these species showed a good relationship with gradients of available soil-moisture.

• 한국산림과학회지
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• 제38권1호
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• pp.46-54
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• 1978

황폐임지(荒廢林地)의 녹화(綠化)에 있어서 그 토양조건(土壤條件)은 지피식생(地被植生)의 초기생육(初期生育)에 지대(至大)한 영향(影響)을 미친다. 황폐지(荒廢地) 토양(土壤)의 수분조건(水分條件)과 인산시비수준(燐酸施肥水準)이 묘목(苗木)의 생장(生長)과 양분흡수(養分吸收)에 미치는 효과(効果)를 알기 위하여 본(本) 시험(試驗)이 실시(實施)되었다. 화강암질(花崗岩質) 토양(土壤)을 채취운반(採取運搬)하여 리기다소나무, 아까시나무 및 싸리를 공시수종(供試樹種)으로 식재(植栽)하였다. 처리수준(處理水準)은 수분처리(水分處理)가 3수준(水準), 인산시비(燐酸施肥)가 4수준(水準)으로 하였으며 각각(各各) 4반복(反復)을 두었다. 시험(試驗) 결과(結果) 생장(生長)은 건중량(乾重量)의 변화(變化)로 고찰(考察)하였고 양분흡수(養分吸收)는 질소(窒素) 인산(燐酸) 가리(加里)에 대(對)하여만 분석(分析) 조사(調査)하였다. 이상과 같이 실시(實施)한 시험(試驗) 결과(結果) 다음과 같은 결론(結論)을 얻었다. 1. 리기다소나무 묘목(苗木)에 있어서 토양수분함량(土壤水分含量)의 증가(增加)는 생장량(生長量)을 증가(增加)시키고 가리(加里)의 흡수(吸收)를 촉진(促進)시키며, 인산시비수준(燐酸施肥水準)의 증가(增加)는 인산흡수(燐酸吸收)에 영향(影響)을 주지 못하며 오히려 가리(加里)의 흡수(吸收)를 감소(減少)시킨다. 2. 아까시나무에 있어서 토양수분함량(土壤水分含量)의 증가(增加)는 식물체내(植物體內) 질소(窒素)와 가리(加里)의 흡수(吸收)를 증가(增加)시키며 인산시비수준(燐酸施肥水準)의 증가(增加)는 인산흡수(燐酸吸收)를 촉진(促進)시킬뿐 아니라 생장량(生長量)을 크게 증가(增加)시킨다. 3. 싸리에 있어서 토양수분함량(土壤水分含量)의 증가(增加)는 질소(窒素)의 흡수(吸收)를 감소(減少)시키는 경향(傾向)이 있으며, 인산시비수준(燐酸施肥水準)의 증가(增加)는 인산흡수(燐酸吸收)를 촉진(促進)시키며 동시(同時)에 생장량(生長量)을 증가(增加)시킨다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 추계 학술발표회
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• pp.404-415
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• 2010

In this paper, using the TDR sensors, variation of soil water content changes were measured as TDR data. Then filtering technique was determined using Fourier transform. Determine the moisture content of soil and ground water level and tried to determine unsaturated zone. First, variation of water content changes were measured TDR data by indoor experiment. Then as a function of TDR data made for water content of soil. Next, through Acrylic indoor laboratory model experiments, changes in ground water levels and lateral penetration of the field conditions were reproduced in an indoor. Field applicability of the TDR sensor was demonstrated by analysis of this. TDR sensor was installed in the embankment, TDR data were measured by TDR sensor.

• 한국환경보건학회지
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• 제22권2호
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• pp.69-82
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• 1996

The samples for testing have been collected from Kangdong-myon, Nongso-myon, Beomseo-my on, and Cheongryang-myon in Ulju-Ku, Ulsan-city from July 1994 to March 1995 in order to grasp status of trace metals contained in some rice, soybean and soils, and to provide references in establishing their standard 96 collected samples(48 for cereals and 48 for soils) have been tested to measure levels of Hg, Pb, Cd, Cu, and Zn through methods of trace metal containing analysis and heavy metal analysis. moisture content was also analyzed. And at the same time 0.1N-HCl soluble heavy metal content of soil was measured. The average Hg containing level of samples is 0.006 ppm for cereal and 0.062 ppm for soil, Pb is 0.302 ppm for cereal and 1.137 ppm for soil, Cd is 0.012 ppm for cereal and 0.027 ppm for soil, Cu is 2.01 ppm for cereal and 0.885 ppm for soil, and Zn is 7.853 ppm for cereal and 2.366 ppm for soil.

• 환경생물
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• 제27권1호
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• pp.82-87
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• 2009

우리나라의 주요 우점종인 상수리나무, 굴참나무, 신갈나무의 생태적 특성을 밝히기 위하여 식물생장에서 가장 중요하다고 판단되는 광, 토양수분, 영양소를 이들 3종의 참나무 유식물에 각각 실내에서 처리하여 그 생육반응을 관찰하고, 분석하고자 시도하였다. 상수리나무와 굴참나무는 광이 높을수록 잘 자라는 경향이 있었고, 신갈나무만이 뚜렷한 경향이 없었다. 신갈나무는 낮은 광도에서도 생육이 크게 감소하지 않았다 굴참나무와 신갈나무는 수분구배에 따라 생육의 차이가 없었고, 상수리나무만이 약간 높은 구배에서 잘 자랐을 뿐이었다. 상수리나무, 굴참나무와 신갈나무 모두는 영양소가 적을 때 잘 자랐고, 높을수록 못 자랐다. 영양소 구배에 따른 감소정도는 굴참나무, 신갈나무, 상수리나무 순으로 낮았다. 이상으로 볼 때, 신갈나무는 피음조건에, 상수리나무는 토양이 다습한 조건에 그리고 굴 참나무는 유기물이 적은 조건에서 각각 적응한 종이라고 판단된다.

• Journal of Ecology and Environment
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• 제45권4호
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• pp.264-276
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• 2021

Background: Salt marshes provide a variety of ecosystem services; however, they are vulnerable to human activity, water level fluctuations, and climate change. Analyses of the relationships between plant communities and environmental conditions in salt marshes are expected to provide useful information for the prediction of changes during climate change. In this study, relationships between the current vegetation structure and environmental factors were evaluated in the tidal flat at the southern tip of Ganghwa, Korea, where salt marshes are well-developed. Results: The vegetation structure in Ganghwa salt marshes was divided into three groups by cluster analysis: group A, dominated by Phragmites communis; group B, dominated by Suaeda japonica; and group C, dominated by other taxa. As determined by PERMANOVA, the groups showed significant differences with respect to altitude, soil moisture, soil organic matter, salinity, sand, clay, and silt ratios. A canonical correspondence analysis based on the percent cover of each species in the quadrats showed that the proportion of sand increased as the altitude increased and S. japonica appeared in soil with a relatively high silt proportion, while P. communis was distributed in soil with low salinity. Conclusions: The distributions of three halophyte groups differed depending on the altitude, soil moisture, salinity, and soil organic matter, sand, silt, and clay contents. Pioneer species, such as S. japonica, appeared in soil with a relatively high silt content. The P. communis community survived under a wider range of soil textures than previously reported in the literature; the species was distributed in soils with relatively low salinity, with a range expansion toward the sea in areas with freshwater influx. The observed spatial distribution patterns may provide a basis for conservation under declining salt marshes.

• 한국전기전자재료학회논문지
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• 제35권5호
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• pp.459-465
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• 2022

This paper reports a method to use a wireless sensor network deployed in the field to real-time monitor soil moisture, warning when the moisture level reaches a specific value, and wirelessly controlling an additional device (LED or water supply system, etc.). In addition, we report all processes related to wireless irrigation system, including field deployment of sensors, real-time monitoring using a smartphone, data calibration, and control of additional devices deployed in the field by smartphone. A commercially available open-source Internet of Things (IoT) platform, NodeMCU, was used, which was combined with a 9V battery, LED and soil humidity sensor to be integrated into a portable prototype. The IoT-based soil humidity sensor prototype deployed in the field was installed next to a tree for on-site demonstration for the measurement of soil humidity in real-time for about 30 hours, and the measured data was successfully transmitted to a smartphone via Wifi. The measurement data were automatically transmitted via e-mail in the form of a text file, stored on the web, followed by analyses and calibrations. The user can check the humidity of the soil real-time through a personal smartphone. When the humidity of a soil reached a specific value, an additional device, an LED device, placed in the field was successfully controlled through the smartphone. This LED can be easily replaced by other electronic devices such as water supplies, which can also be controlled by smartphones. These results show that farmers can not only monitor the condition of the field real-time through a sensor monitoring system manufactured simply at a low cost but also control additional devices such as irrigation facilities from a distance, thereby reducing unnecessary energy consumption and helping improve agricultural productivity.

• 한국농공학회논문집
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• 제58권4호
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• pp.21-35
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• 2016

This study is to evaluate the applicability of SWAT (Soil and Water Assessment Tool) model for multi-purpose dams and multi-function weirs operation in Namhan river basin ($12,577km^2$) of South Korea. The SWAT was calibrated (2005 ~ 2009) and validated (2010 ~ 2014) considering of 4 multi-purpose dams and 3 multi-function weirs using daily observed dam inflow and storage, evapotranspiration, soil moisture, and groundwater level data. Firstly, the dam inflow was calibrated by the five steps; (step 1) the physical rate between total runoff and evapotranspiration was controlled by ESCO, (step 2) the peak runoff was calibrated by CN, OV_N, and CH_N, (step 3) the baseflow was calibrated by GW_DELAY, (step 4) the recession curve of baseflow was calibrated by ALPHA_BF, (step 5) the flux between lateral flow and return flow was controlled by SOL_AWC and SOL_K, and (step 6) the flux between reevaporation and return flow was controlled by REVAPMN and GW_REVAP. Secondly, for the storage water level calibration, the SWAT emergency and principle spillway were applied for water level from design flood level to restricted water level for dam and from maximum to management water level for weir respectively. Finally, the parameters for evapotranspiration (ESCO), soil water (SOL_AWC) and groundwater level fluctuation (GWQMN, ALPHA_BF) were repeatedly adjusted by trial error method. For the dam inflow, the determination coefficient $R^2$ was above 0.80. The average Nash-Sutcliffe efficiency (NSE) was from 0.59 to 0.88 and the RMSE was from 3.3 mm/day to 8.6 mm/day respectively. For the water balance performance, the PBIAS was between 9.4 and 21.4 %. For the dam storage volume, the $R^2$ was above 0.63 and the PBIAS was between 6.3 and 13.5 % respectively. The average $R^2$ for evapotranspiration and soil moisture at CM (Cheongmicheon) site was 0.72 and 0.78, and the average $R^2$ for groundwater level was 0.59 and 0.60 at 2 YP (Yangpyeong) sites.

• 대한토목학회논문집
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• 제38권4호
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• pp.537-545
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• 2018

설계홍수량 산정 시 도달시간과 같은 시간매개변수의 결정은 매우 중요한 요소이다. 도달시간은 주로 홍수 및 하천관리를 위해 이용되고 있으며, 평수기의 도달시간은 하천의 유지유량 및 이수관리를 위해 이용되고 있다. 자연하천에 대한 도달시간 산정은 주로 유역의 지형학적 인자를 기반으로 산정하고 있으며, 지형학적 인자 이외에 유출곡선지수, 유속, 강우강도의 인자를 고려하여 도달시간을 산정하고 있다. 그러나 재현기간별 강우조건과 토양함수상태를 함께 고려한 도달시간의 산정연구는 부재한 상황이다. 따라서 본 연구는 재현기간별 강우조건과 토양함수상태를 고려하여 임진강의 황강댐과 임진교 수위관측소 구간을 자연하천으로 설정한 경우와 황강댐의 방류량 조건에 따라 임진교 수위관측소에 도달하는 경우로 구분하여 도달시간을 산정하였다. 자연하천으로 설정한 구간에 대해서는 기 개발된 도달시간 산정방법과 비교 검토를 통해 결과를 입증하였으며, 이를 토대로 황강댐의 방류량 조건별 도달시간을 산정하였다. 본 연구에서 제시된 도달시간은 임진강 유역의 홍수관리와 황강댐 방류시 위험에 대비할 수 있는 시간을 확보할 수 있다.

• 한국약용작물학회지
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• 제16권4호
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• pp.207-210
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• 2008

비닐하우스 내에서 일평균 투광율을 21.2%, 24.8%, 30.3%와 같이 3수준으로, 토양수분을 11.0%, 12.5%, 15.3%, 18.9%와 같이 4수준으로 조절하여 묘삼의 생육 및 수량을 조사한 결과는 다음과 같다. 엽록소 함량은 투광율이 낮은 조건에서 토양수분함량의 감소에 따라 완만히 감소되었으나 투광량이 높은 조건에서 토양수분함량이 낮아지면 엽록소 함량은 현저히 감소되었다.고온장해율은 투광율이 낮은 조건에서 토양수분함량이 11.0%처럼 매우 낮을 때에만 현저히 증가되었지만 투광량이 높은 조건에서는 토양수분함량의 감소에 따라 고온장해율은 급격히 증가되었다. 3.3$m^2$(칸)당 생근중, 주당 생근중 및 사용가능묘삼수는 투광율이 증가되고 토양수분함량이 감소될수록 뚜렷이 감소되었는데, 토양수분함량이 적절한 조건(18.9%)에서는 투광율이 증가되어도 묘삼수량의 감소는 적었으나 토양수분함량이 부족한 조건에서는 투광율이 증가될수록 묘삼수량은 현저히 감소되었다. 적변율은 투광율이 높고 토양수분함량이 많을 때 현저히 증가되었는데, 투광율이 높은 조건에서 토양수분함량이 감소되면 적변율도 차차 감소되었으며, 투광율이 낮은 조건에서 적변율은 토양수분함량에 따라 큰 변화를 보이지 않았다.