• 한국농공학회지
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• 제40권1호
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• pp.88-95
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• 1998

Salt accumulation is frequently experienced in soils under protected cultivation. Since protected cultivation does not bave rainfall and resulting infiltration, salt accumulation in the soils is inevitable. In this study, analyzed were chemical characteristics of soils under protected cultivation to investigate the factors which may contribute the salt accumulation. Soil samples were collected from 99 protected cultivation facilities around Ansung-Gun, Gyungki-Do and analyzed for electrical conductivity, PH, organic matter contents. The results showed that there was no significant trend of changes in electrical conductivity and pH along cultivation years. The only factor influencing salt acculmuation was irrigation type. Soils in facilities using drip irrigation showed higher electrical conductivity than these using diversion-hose type irrigation.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1998년도 공동 심포지엄 및 추계학술발표회
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• pp.206-215
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• 1998

Using of geosynthetics with linear materials(sand, gravel, clay soil) is rapidly increased in landfill. With geosynthetics, geotextiles often expose to solar radiation(Ultraviolet) on long terms during the installation. In this paper, the results will represent the strength retention rate and tensile retention rate of geotextiles between outdoor exposed and protected by 15cm thickness of soil. As a result of cumulating solar radiation in geotextiles was increased, the strength retentions rate of P.P(500g/$m^2$), P.P(700g/$m^2$) and P.P(1000g/$m^2$) were decreased and the lower weight of unit area of geotextiles, the faster decrease of strength retention rate. P.E.T(600g/$m^2$) was showed a distinctive trend that the strength retention rate increased. The tensile retention rate of tested geotextiles was decreased during the simulation. However, the strength and tensile retention rate of geotextiles covered by soil had changed insignificantly. Therefore, it can surmise that the soil covering will help geotextiles to be protected from UV effecting

• 생물환경조절학회지
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• 제22권4호
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• pp.378-384
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• 2013

파프리카의 토양재배면적 증가에 따라 관비재배법의 확립이 요구되고 있다. 관비재배(Fertigation)는 물과 양분을 함께 공급하는 방법으로 작물의 수분과 양분의 과부족에 의한 장해없이 근권을 안정적으로 유지할 수 있다. 본 연구에서는 시설 파프리카의 관비재배시 토양수 분포텐셜에 따른 과실 품질 및 수량의 효과를 구명코자 실험을 수행하였다. '쿠프라' 및 'E499524' 2품종을 공시하여 정식 후부터 수확기까지 토양수분포텐셜을 -10, -20 그리고 -30kPa로 처리구를 두었다. 초장은 토양수분포텐셜이 높은 -10kPa 처리구가 가장 길었다. 과실의 평균 과중은 '쿠프라' 품종에서는 평균과중은 -20kPa에서 154.5kg으로 가장 무거웠으며 토양수분포텐셜이 낮은 -30kPa에서는 138.2kg으로 가벼웠다. 주당 착과수는 5.1~5.3개로 '쿠프라' 품종은 토양수분포텐셜에 따른 차이가 없었으나 'E499524' 품종은 -20kPa 처리구에서 10.3개로 가장 많았다. 상품수량은 '쿠프라' 품종은 -20kPa 처리구에서 2,321kg/10a로 가장 많았고 그리고 'E499524' 품종은 -20kPa 처리구에서 1,147kg/10a로 가장 많았다. '쿠프라' 품종에서는 과장과 과폭은 토양수분포텐셜에 따른 차이가 없었으나 'E499524' 품종은 토양수분포텐셜이 낮을수록 작은 경향을 보였다. 과실의 당도는 '쿠프라' 품종에서는 4.4~4.9oBrix, 그리고 'E499524' 품종에서는 7.6~8.3oBrix로 토양수분포텐셜에 따른 통계적 유의차가 없었다. 자방수는 '쿠프라' 품종에서는 3.3~3.6개, 그리고 'E499524' 품종에서는 2.5~2.7개로 토양수분포텐셜 간에 유의차이가 없었다. 과실의 열과 발생율은 '쿠프라' 및 'E499524' 품종 모두 토양수분포텐셜 낮을수록 적은 경향을 보였다. 식물체 내 질소의 함량은 토양수분포텐셜에 따른 차이가 없었으며 '쿠프라' 품종은 2.10~2.22%였고 'E499524' 품종은 1.72~1.82%였다. '쿠프라' 및 'E499524' 품종 모두 토양수분포텐셜에 따른 식물체의 칼륨, 칼슘, 마그네슘 등 무기 양분의 함량은 유의차이가 없었다. 이상의 결과에서 파프리카의 여름철 관비재배시 토양수분포텐셜을 -20kPa로 설정하는 것이 생육이 가장 좋은 것으로 판단되었다.

• 한국환경농학회지
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• 제29권4호
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• pp.328-335
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• 2010

이 실험은 관비재배시 토양 pH와 질소 비종이 토마토 생육과 토양화학성에 미치는 영향에 대해 조사하고자 수행하였다. 시험작물은 동양계 품종인 '슈퍼도태랑'을 이용하여 18 L포트에서 3개월간 재배하였으며 토양 pH를 6.88과 8.77 두수준으로 조절하였다. 주요 관비 비종인 요소, 질산암모늄, 황산암모늄, 질산칼륨를 이용하였으며 관비 농도는 0, 10, 50, 100 mg N/L로 조절하였다. 토양의 pH가 8.77일 때 pH 6.88에 비하여 수량과 엽록소 형광반응이 감소하였으나 질산암모늄과 황산암모늄을 이용하여 관비할 경우 토마토 수량이 증가하는 것으로 나타났다. pH 6.88일 경우 비종보다는 관비 농도가 증가할수록 수량이 증가하였다. 토마토 재배후 비종에 따른 화학성 변화를 살펴보면 토양의 pH는 질산암모늄과 황산암모늄을 시용하였을 경우 감소하였으며 질산 칼륨 시용 시 토양 pH와 칼륨함량이 높아졌다. 토양 내 EC는 황산암모늄 100 mg N/L 시용 시 다른 비종에 비하여 2배 이상 높아졌다. 질산태질소와 암모늄태 질소는 비종별로 크게 차이는 없었지만 pH가 높을 때 토양 내 함량이 적은 것으로 나타났다. 이 실험 결과 요소와 질산암모늄을 관비용 비종으로 이용하면 토마토 재배 전 후 토양화학성의 변화가 크지 않은 것으로 나타났다.

• 원예과학기술지
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• 제35권1호
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• pp.79-87
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• 2017

We examined the effect of two greenhouse covering materials (glass or solid polycarbonate sheets) on the light environment and growth of tomato and cucumber plants. Spectral analysis showed that polycarbonate sheets entirely blocked radiation in both the UV - B (300 - 320 nm) and UV - A (320 - 400 nm) ranges, whereas glass transmitted UV - A and was only opaque to UV - B. The transmittance of photosynthetically active radiation (400 - 700 nm) and near infrared radiation (700 - 1100 nm) was higher in polycarbonate than glass. Air and soil temperatures were not significantly different between greenhouses covered with either material. The growth of cucumber plants was slightly affected by covering materials, whereas no significant changes in growth parameters were observed for tomato plants. The color parameters of tomato fruits were affected by the cover material, whereas cucumber fruits showed similar coloration in both glass and polycarbonate greenhouses.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1998년도 학술발표회 발표논문집
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• pp.237-242
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• 1998

Salt accumulation is frequently experienced in soils under protected cultivation. Since protected cultivation does not have rainfall and resulting infiltration, salt accumulation in the soils is inevitable. In this study, analyzed were chemical charecteristics of soils under protected cultivation to investigate the factors which may contribute the salt accumulation. Soil samples were collected from 99 protected cultivation facilities around An-sung Gun, Gyungki-Do and analyzed for electrical conductivity, pH, organic matter con-tents. The results showed that there was no significant trend of changes in electrical conductivity and pH along cultivation years. the only factor influencing salt accumulation was irrigation type. Soils in facilities using drip irrigation showed higher electrical conductivity than those using diversion-hose type irrigation.

• Corrosion Science and Technology
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• 제5권3호
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• pp.112-116
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• 2006

This study has been conducted to monitor the corrosion rate of cathodically protected structure and corrosion inhibited system using multi-line thin-film electrical resistance (TFER) sensor in various environments. The field test data of TFER sensor for the corrosion monitoring of cathodically protected underground pipeline in soil environments and of corrosion inhibited gas heaters were also presented. The sensor was found to be a powerful method to commit the sensitive pick-up of small corrosion rate which can be observed in the cathodically protected and corrosion inhibited systems.

• 농업과학연구
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• 제38권4호
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• pp.747-752
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• 2011

Wireless technology has enabled farmers monitor and control protected production environment more efficiently. Utilization of USN (Ubiquitous Sensor Network) devices also brought benefits due to reduced wiring and central data handling requirements. However, wireless communication loses signal under unfavorable conditions (e.g., blocked signal path, low signal intensity). In this paper, performance of commercial wireless communication devices were evaluated for application to protected crop production. Two different models of wireless communication devices were tested. Sensors used in the study were weather units installed outside and top of a greenhouse (wind velocity and direction, precipitation, temperature and humidity), inside ambient condition units (temperature, humidity, $CO_2$, and light intensity), and irrigation status units (irrigation flow and pressure, and soil water content). Performance of wireless communication was evaluated with and without crop. For a 2.4 GHz device, communication distance was decreased by about 10% when crops were present between the transmitting and receiving antennas installed on the ground, and the best performance was obtained when the antennas were installed 2 m above the crop canopy. When tested in a greenhouse, center of a greenhouse was chosen as the location of receiving antenna. The results would provide information useful for implementation of wireless environment monitoring system for protected crop production using USN devices.

• Journal of Ecology and Environment
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• 제43권1호
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• pp.61-72
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• 2019

Background: Organic carbon stored in coastal wetlands, which comprises the major part of oceanic "blue carbon," is a subject of growing interest and concern. In this study, organic carbon storage in coastal wetlands and its economic value were estimated using the raw data of 25 studies related to soil carbon storage. Data were collected from three tidal flats (one protected and two developed areas) and two estuarine salt marshes (one protected and one restored area). Bulk density, soil organic matter content, and standing biomass of vegetation were all considered, with Monte Carlo simulation applied to estimate the uncertainty. Results: Mean carbon storage in two salt marshes ranged between 14.6 and $25.5kg\;C\;m^{-2}$. Mean carbon storage in tidal flats ranged from 18.2 to $28.6kg\;C\;m^{-2}$, with variability possibly related to soil texture. The economic value of stored carbon was estimated by comparison with the price of carbon in the emission trading market. The value of US $ $6600\;ha^{-1}$ is ~ 45% of previously estimated ecosystem services from fishery production and water purification functions in coastal areas. Conclusions: Although our study sites do not cover all types of large marine ecosystem, this study highlights the substantial contribution of coastal wetlands as carbon sinks and the importance of conserving these habitats to maximize their ecosystem services.

• 생물환경조절학회지
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• 제13권3호
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• pp.156-161
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• 2004

시설참외 재배지 연작장해 경감을 위한 객토시 토성이 생육과 과실의 품질 및 수량에 미치는 영향을 조사하였다. 객토시 기존 작토층에 함유된 유ㆍ무기물질들은 교반으로 감소되었고, 토양수분 장력은 점토함량이 낮은 사양토가 양토와 미사질식토 보다 감소폭이 크게 나타났으나 토양경도의 증가폭은 낮았다. 초기 생육은 사양토에서 초장과 엽면적 그리고 지상ㆍ지하부 생체중과 건물중이 모두 높은 경향을 보였으나 엽록소함량은 낮았다. 과실은 사양토에서 크고 무거웠으며 단도와 색은 미사질식토에서 높게 나타났다. 상품과와 비상품과 수량은 사양토에서 가장 많았으며 또한 발효과 발생률도 높게 나타났다. 저장기간이 경과할수록 모든 토성에서 경도와 과중은 서서히 감소되었으나 당도는 저장 후 5일까지 증가한 후 감소되었다. 따라서 시설참외 재배지 객토시 과실의 품질과 수량에 영향을 미치는 토성이 고려되어야 하겠다.