• Title/Summary/Keyword: EC2

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Screening of Adsorbent to Reduce Salt Concentration in the Plastic Film House Soil under Continuous Vegetable Cultivation (시설채소재배지의 토양특성과 흡착제 종류별 염류경감 효과)

  • Ok, Yong-Sik;Yoo, Kyung-Yoal;Kim, Yoo-Bum;Chung, Doug-Young;Park, Yong-Ha;Yang, Jae-E.
    • Korean Journal of Environmental Agriculture
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    • v.24 no.3
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    • pp.253-260
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    • 2005
  • Salt accumulation in the plastic film house soils under continuous cultivation condition causes problems such as salt damages to plants, nitrate accumulation in vegetables, groundwater contamination, etc. due to excess application of fertilizers. Objective of this research was to find an optimum adsorbent to reduce salt concentration in the soil solution of plastic film house soils, where crop injuries have been observed due to the salt accumulation. The soils were significantly high in available P $(1,431{\sim}6,516mg\;kg^{-1}),\;NO_3-N\;(117.60{\sim}395.73mg\;kg^{-1})$, exchangeable Ca $(4.06{\sim}11.07\;cmol_c\;kg^{-1})$ and Mg $(2.59{\sim}18.76\;cmol_c\;kg^{-1})$, as compared to those of the average upland soils in Korea. Soils were treated with each of adsorbent such as ion-exchange resin, zeolite, rice bran, etc. at 2% level and prepared into saturated-paste samples. After equilibrium, soil solution was vacuum-extracted from the soil and measured for changes of the pH, EC, and concentrations of $Ca^{2+},\;Mg^{2+},\;K^+,\;Na^+,\;{NH_4}^+,\;{PO_4}^{3-}\;and\;{NO_3}^-$. Rice bran effectively removed ${PO_4}^{3-}\;and\;{NO_3}^-$ in the soil solution up to 100%. Efficiency was decreased in the orders of rice bran > ion-exchange resin > zeolite. Removal efficiencies of zeolite and ion-exchange resin for $Ca^{2+}$ were ranged from 1 to 65% and from 7 to 61%, respectively. Ion-exchange resin was also effective for removing $Mg^{2+},\;K^+,\;Na^+,\;and\;{NH_4}^+$. Overall results demonstrated that rice bran and ion-exchange resin could be applicable for salt accumulated soil to remove the respective anion and cation.

Ecological Health Assessment of Dongjin River Based on Chemical Measurement and Fish Assemblage Analysis. (동진강의 이.화학적 수질 및 서식지 분석을 통한 어류 생태영향 평가)

  • Kim, Yu-Pyo;Lee, Eui-Haeng;An, Kwang-Guk
    • Korean Journal of Ecology and Environment
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    • v.42 no.2
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    • pp.183-191
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    • 2009
  • This study was to evaluate ecological health of Dongjin River in October 2007. The ecological health assessments was based on the Index of Biological Integrity (IBI), Qualitative Habitat Evaluation Index (QHEI), and water chemistry. For the study, the models of IBI and QHEI were modified as 8 and 11 metric attributes, respectively. We also analyzed spatial patterns of chemical water quality over the period of 2005${\sim}$2008, using the water chemistry dataset, obtained from the Ministry of Environment, Korea. In Dongjin River, values of IBI averaged 19 (n=3), which is judged as a "Fair" condition after the criteria of Barbour et al. (1999). There was a distinct spatial variation. IBI score at Site 1 was estimated as 28, indicating a "Good" condition whereas, IBI at Site 2 and Site 3 were as 18 and 12, indicating "Fair" and "Poor" condition, respectively. Habitat analysis showed that QHEI values in the river averaged 117 (n=3), indicating a "Fair${\sim}$Good" condition after the criteria of Barbour et al. (1999). Values of BOD and COD averaged 2.3 mg $L^{-1}$ (scope: 0.1${\sim}$8.9 mg $L^{-1}$) and 5.5 mg $L^{-1}$ (scope: 1.8${\sim}$12.6 mg $L^{-1}$), respectively during the study. Total nitrogen (TN) and total phosphorus (TP) averaged 2.7mg $L^{-1}$ and 0.127mg $L^{-1}$, respectively, and the nutrients showed large longitudinal gradients between the upper and lower reach. Overall, dataset of IBI, QHEI, and water chemistry showed that river health was a gradual decline at upstream to downstream. So, Dongjin River should be protected from habitat disturbance and chemical pollutions.

Diagnosis of Real Condition and Distribution of Protected Trees in Changwon-si, Korea (창원시 보호수의 분포현황과 실태진단)

  • You, Ju-Han;Park, Kyung-Hun;Lee, Young-Han
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.29 no.1
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    • pp.59-70
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    • 2011
  • The purpose of this study is to present raw data to systematically and rationally manage the protected trees located in Changwon-si, Korea. This study investigated about the present condition and the information of location, individual, management, health and soil. The results are as follows. The protected trees were located in 26 spots, and species of trees were 9 taxa; Zelkova serrata, Celtis sinensis, Aphananthe aspera, Ginkgo biloba, Carpinus tschonoskii, Pinus densiflora for. multicaulis, Quercus variabilis, Pinus densiflora and Salix glandulosa. In protected tree types, shade trees were the most, and the majority of theirs were 200 years or more in age. The range of altitude was 14~173m, and the number of trees located in flat fields was the most. For location types, village and field and mountain were presented in the order and, in land use, land for building was the most. The range of height was 8.0~30.0m, 0.6~5.1m in crown height, 240~700cm in diameter of breast and 210~800cm in diameter of root. In case of crown area, Zelkova serrata of No.5 was most large. The status boards were mostly installed except No.23 and No.26. The sites with fence were 9 spots, and the site with stonework were 14 spots. The sites with the support beam were 5 spots, and most sites were not covered up with soil. The materials of bottom were soil, gravel and vegetation in the order. The range of withering branch rate was 0~40%, and peeled bark rate was 0~60%. The sites made holes were 23 spots, and the hole size of Aphananthe aspera of No.12 was the largest. The sites disturbed by human trampling were 7 spots, the sites by disease and insects of 2 spots, the sites by injury of 23 spots and the sites by exposed roots of 13 spots. In the results of soil analysis, there showed that acidity was pH 4.5~8.0, organic matter content of 3.5~69.8g/kg, electrical conductivity(EC) of 0.11~2.87dS/m, available $P_2O_5$ of 3.0~490.6mg/kg, exchangeable K of 0.10~1.05cmol+/kg, exchangeable Ca of 1.41~16.45cmol+/kg, exchangeable Mg of 0.37~1.96cmol+/kg, exchangeable Na of 0.25~2.41cmol+/kg and cation exchange capacity(C.E.C) of 8.35~26.55cmol+/kg.

이앙시기 및 재식밀도별 다복찰과 동진찰 생육 특성

  • 유영석;김효진;강영호;최유나;조대호;김주
    • Proceedings of the Korean Society of Crop Science Conference
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    • 2022.10a
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    • pp.103-103
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    • 2022
  • 다복찰은 전라북도농업 기술원에서 2012~2020년에 신명흑찰과 익산488호를 교배하여 육성한 찰벼이며, 중대립, 단간, 내도복, 다수성의 특징을 보인다. 동진찰은 1998년도에 육성되었으며, 우리나라에서 가장 인기 있는 찰벼이다(재배면적 25,161ha/2021년 기준). 드문모심기 재배 기술은 2017년부터 도입되었으며, 밀파 육묘하여 재식밀도 및 재식주수를 감소함으로써 소요되는 재료비 등 경비 및 투입되는 노동력을 절감하는 경제성 있는 기술이다. 따라서 본 연구는 전라북도농업기술원에서 육성한 다복찰 보급 확대 및 가장 인기 높은 동진찰의 드문모심기 재배기술 확립 일환으로 시작되었으며, 2024년까지 3년간 실시할 계획이다. 시험은 기술원 논 포장에서 실시하였으며, 시험품종은 다복찰, 동진찰, 시험요인은 이앙시기(3처리) 및 재식밀도(4처리)를 두었다. 이앙시기별로 이앙 17일 전에 온탕소독(62℃, 10분), 종자소독(32℃, 1일), 침종(32℃, 1일), 간이출하(30℃, 3일) 과정을 거쳐 부직포 육묘(12일 정도)를 실시하였다. 5월20일(이앙520)부터 5월30일(이앙530), 6월9일(이앙609)까지 10일 간격으로 드문모심기 전용 이앙기로 이앙하였으며, 주당 본수는 5.7개 정도였다. 이앙 시기별로 시험포장을 구분하였고 포장내에 2품종, 각각 3.3m2당 80주, 60주, 50주, 37주 등 재식밀도 처리구를 두었으며, 처리구마다 3반복 조사구(10주/반복, 5본/주) 설치하였다. 10a당 9-4.5-5.7kg(N-P2O5-K2O)를 밑거름(50%)-분얼거름(20)-이삭거름(30) 등 3회 거쳐 시비하였다. 중간물떼기는 이앙32일째부터 10일간 실시하였으며, 예상 출수 30일 전에 충분하게 담수하였다. 이앙20일째부터 10일 간격으로 경수, 초장, 엽색도 등 생육 조사, 그리고 출수기, 후기 생육 및 병해충을 조사하였다. 향후 수확기에 수량, 수량구성요소, 미질 및 품위를 분석할 계획이다. 시험토양은 pH 6.0~6.3, EC는0.68~0.85dS/m, 유기물함량은 52~57g/kg 수준으로 높았다. 동진찰 발아율(94.0~98.1%)이 다복찰(89.9~94.9%)보다 우수하였다(3~6%P ↑). 다복찰 묘 충실도(102~106mg/주)가 동진찰(79~101mg/주)보다 다소 좋았으며, 이앙530 묘소질이 가장 좋았다. 동진찰 초장은 다복찰에 비해 다소 길었으나 이앙시기 및 재식밀도별 초장의 변화 유형은 비슷하였다. 이앙520구의 80주에서 초장이 가장 작았고 이앙609구에서는 80주에서 다소 길었으나, 처리구간의 유의성은 없었다. 동진찰 및 다복찰 경수는 37주에서 이앙 후 40일째, 50주, 60주, 80주에서는 30일째 가장 컸다. 출수기는 다복찰에 비해 동진찰이 3~7일 정도 빨랐으며, 특히 이앙520 동진찰에서는 재식밀도가 높을수록 출수기가 빠른 경향을 보였으며, 이앙530 이후에는 재식밀도간 차이가 거의 없었다. 동진찰에 비해 다복찰 간장이 3~6cm 작았으며, 2품종 모두 이앙609구에서 가장 낮은 값을 보였다. 수장도 간장과 비슷한 경향을 보였다. 수수는 2품종 모두 이앙이 늦을수록 증가하였으며, 37주에서 가장 높았으며, 80주에 비해 다복찰, 동진찰 각각 73.8%, 77.4% 높았다. 다복찰의 경우 3.3m2당 수수는 이앙시기별과 관계없이 상대적으로 80주에서 가장 많았고 이앙520에서 재식밀도간 차이는 감소하였지만 이앙시기가 늦을수록 수수는 증가하는 경향을 보였다. 동진찰도 비슷한 경향을 보였으며, 이앙520과 이앙609 사이에 수수 차이는 적었다. 병 발생은 잎집무늬마름병, 세균성벼알마름병, 이삭누룩병이 주로 관찰되었으며, 세균성 벼알마름병은 출수기와 맞물린 이앙530에서 가장 크게 발생하였으며, 이앙520도 비슷한 경향을 보였다. 이삭누룩병 발생이 심하였는데 재식밀도간 차이보다는 이앙시기별 차이가 더 크게 발생하였으며 품종 간의 병 발생 차이는 없었다. 이상의 결과로 수수 측면에서 조기 이앙할 경우에는 50~60주, 늦은 이앙 시에는 80주가 유리할 것으로 보이며, 추후주당 립수, 등숙률, 천립중 등을 조사하고 경영비 등을 고려하여 합리적인 이앙시기 및 재식밀도를 판단할 수 있을 것으로 판단된다.

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Analysis and Implication on the International Regulations related to Unmanned Aircraft -with emphasis on ICAO, U.S.A., Germany, Australia- (세계 무인항공기 운용 관련 규제 분석과 시사점 - ICAO, 미국, 독일, 호주를 중심으로 -)

  • Kim, Dong-Uk;Kim, Ji-Hoon;Kim, Sung-Mi;Kwon, Ky-Beom
    • The Korean Journal of Air & Space Law and Policy
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    • v.32 no.1
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    • pp.225-285
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    • 2017
  • In regard to the regulations related to the RPA(Remotely Piloted Aircraft), which is sometimes called in other countries as UA(Unmanned Aircraft), ICAO stipulates the regulations in the 'RPAS manual (2015)' in detail based on the 'Chicago Convention' in 1944, and enacts provisions for the Rules of UAS or RPAS. Other contries stipulates them such as the Federal Airline Rules (14 CFR), Public Law (112-95) in the United States, the Air Transport Act, Air Transport Order, Air Transport Authorization Order (through revision in "Regulations to operating Rules on unmanned aerial System") based on EASA Regulation (EC) No.216/2008 in the case of unmanned aircaft under 150kg in Germany, and Civil Aviation Act (CAA 1998), Civil Aviation Act 101 (CASR Part 101) in Australia. Commonly, these laws exclude the model aircraft for leisure purpose and require pilots on the ground, not onboard aricraft, capable of controlling RPA. The laws also require that all managements necessary to operate RPA and pilots safely and efficiently under the structure of the unmanned aircraft system within the scope of the regulations. Each country classifies the RPA as an aircraft less than 25kg. Australia and Germany further break down the RPA at a lower weight. ICAO stipulates all general aviation operations, including commercial operation, in accordance with Annex 6 of the Chicago Convention, and it also applies to RPAs operations. However, passenger transportation using RPAs is excluded. If the operational scope of the RPAs includes the airspace of another country, the special permission of the relevant country shall be required 7 days before the flight date with detail flight plan submitted. In accordance with Federal Aviation Regulation 107 in the United States, a small non-leisure RPA may be operated within line-of-sight of a responsible navigator or observer during the day in the speed range up to 161 km/hr (87 knots) and to the height up to 122 m (400 ft) from surface or water. RPA must yield flight path to other aircraft, and is prohibited to load dangerous materials or to operate more than two RPAs at the same time. In Germany, the regulations on UAS except for leisure and sports provide duty to avoidance of airborne collisions and other provisions related to ground safety and individual privacy. Although commercial UAS of 5 kg or less can be freely operated without approval by relaxing the existing regulatory requirements, all the UAS regardless of the weight must be operated below an altitude of 100 meters with continuous monitoring and pilot control. Australia was the first country to regulate unmanned aircraft in 2001, and its regulations have impacts on the unmanned aircraft laws of ICAO, FAA, and EASA. In order to improve the utiliity of unmanned aircraft which is considered to be low risk, the regulation conditions were relaxed through the revision in 2016 by adding the concept "Excluded RPA". In the case of excluded RPA, it can be operated without special permission even for commercial purpose. Furthermore, disscussions on a new standard manual is being conducted for further flexibility of the current regulations.

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Optimization of Analytical Methods for Ochratoxin A and Zearalenone by UHPLC in Rice Straw Silage and Winter Forage Crops (UHPLC를 이용한 볏짚 사일리지와 동계사료작물의 오크라톡신과 제랄레논 분석법 최적화)

  • Ham, Hyeonheui;Mun, Hye Yeon;Lee, Kyung Ah;Lee, Soohyung;Hong, Sung Kee;Lee, Theresa;Ryu, Jae-Gee
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.36 no.4
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    • pp.333-339
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    • 2016
  • The objective of this study was to optimize analytical methods for ochratoxin A (OTA) and zearalenone (ZEA) in rice straw silage and winter forage crops using ultra-high performance liquid chromatography (UHPLC). Samples free of mycotoxins were spiked with $50{\mu}g/kg$, $250{\mu}g/kg$, or $500{\mu}g/kg$ of OTA and $300{\mu}g/kg$, $1500{\mu}g/kg$, or $3000{\mu}g/kg$ of ZEA. OTA and ZEA were extracted by acetonitrile and cleaned-up using an immunoaffinity column. They were then subjected to analysis with UHPLC equipped with a fluorescence detector. The correlation coefficients of calibration curves showed high linearity ($R^2{\geq_-}0.9999$ for OTA and $R^2{\geq_-}0.9995$ for ZEA). The limit of detection and quantification were $0.1{\mu}g/kg$ and $0.3{\mu}g/kg$, respectively, for OTA and $5{\mu}g/kg$ and $16.7{\mu}g/kg$, respectively, for ZEA. The recovery and relative standard deviation (RSD) of OTA were as follows: rice straw = 84.23~95.33%, 2.59~4.77%; Italian ryegrass = 79.02~95%, 0.86~5.83%; barley = 74.93~97%, 0.85~9.19%; rye = 77.99~96.67%, 0.33~6.26%. The recovery and RSD of ZEA were: rice straw = 109.6~114.22%, 0.67~7.15%; Italian ryegrass = 98.01~109.44%, 1.65~4.81%; barley = 98~113.53%, 0.25~5.85%; rye = 90.44~108.56%, 2.5~4.66%. They both satisfied the standards of European Commission criteria (EC 401-2006) for quantitative analysis. These results showed that the optimized methods could be used for mycotoxin analysis of forages.

Evaluation of Soil and Fertilizer Management Techniques Applied by Farmers in Forcing and Semi-forcing Cucumber Cultivation Facilities (오이 촉성재배와 반촉성재배 농가들의 토양 및 시비관리기술 평가)

  • Lee, Ju-Young;Jang, Byoung-Choon;Sung, Jwa-Kyung;Lee, Su-Yeon;Kim, Rog-Young;Lee, Ye-Jin;Park, Yang-Ho;Kang, Sung-Soo;Hyun, Byung-Keun
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.983-991
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    • 2012
  • These days, agricultural products cultivated in facilities occupy the highest percentage of agricultural output price. Specifically cucumbers have been one of the crops that farmers prefer to growing, because their prices were high. However, cucumber crop is sensitive to the soil and environments and it requires the exact crop management. In order to establish cultivation techniques for cucumbers, the current situation of cucumber cultivation was surveyed from ten cucumber farmlands; five farmlands of cucumber cultivation in forcing and five of semi-forcing practicing systems, respectably. The soil conditions were alluvial or valley in soil topology, moderately or poorly drainage in soil drainage classes, coarse loamy in soil texture family. Soil was managed with deep plowing combined with application of basal fertilizers such as compost, rice straw, oil cake, wood chip and chemical fertilizer. The whole soil was prepared in uniformly with rotary. Three major nutrients ($N-P_2O_5-K_2O$)of basal application were 815-464-529 kg $ha^{-1}$ in forcing and 197-135-151 kg $ha^{-1}$ in semi-forcing cultivation. Top dressing of fertilizer was supplied in fertigation system of macro and micro elements in 2~3 day interval with water irrigation. The average yields of cucumbers were $168t\;ha^{-1}$ with 381,000 thousand won $ha^{-1}$ in average gross profit (AGP) in forcing cultivation and $115t\;ha^{-1}$ with 177,000 thousand won $ha^{-1}$ in AGP in semi-forcing cultivation. Cucumber production during the winter season was considered to increase the gross profit because cucumber price tends to stay in high level during this time. The accumulation of soil chemicals like EC, available $P_2O_5$ and exchangeable cations could be controlled by rice straw application. The rice straw application increased soil temperature during the winter season, in exchange of soil air, and in extension of plant roots. In addition, the rice straw application somewhat affected decrease of salts accumulation.

Quality Properties of Appenzeller Cheese Containing Green Tea Powder (녹차 첨가 아펜젤러 치즈의 품질 특성)

  • Choi, Hee-Young;Choi, Hyo-Ju;Yang, Chul-Ju;Lee, Sang-Suk;Choi, Gap-Sung;Park, Jeong-Ro;Chun, Sun-Sil;Shin, Hyon-Jung;Jeong, Seok-Geun;Bae, In-Hyu
    • Journal of Dairy Science and Biotechnology
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    • v.27 no.2
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    • pp.7-16
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    • 2009
  • Appenzeller cheese samples were prepared by addition of 0.5, 1.0, and 2.0% green tea (Camellia sinensis, CS) powder and control cheese. We examined various quality characteristics of the novel cheese, such as viable-cell counts, pH, water-soluble nitrogen (WSN), non-casein nitrogen (NCN), non-protein nitrogen (NPN), and catechin level during maturation for 16 weeks at $14^{\circ}C$. To develop a Korean natural cheese containing green tea powder, we also analyzed the changes in the polyacrylamide gel electrophoresis pattern, chemical composition, and sensory qualities. The viable cell counts of the samples were not significantly different. Until the $3^{rd}$ week, the pH of the CS cheese decreased with an increase in the maturation time. However, the pH gradually increased by the $12^{th}$ week, while WSN, NCN, NPN also increased. The WSN, NCN, NPN, and catechin values for the CS cheese samples were significantly higher than the values for the control cheese. The polyacrylamide gel electrophoretic pattern of caseins for the CS cheese indicated that this cheese degraded more rapidly than the control cheese did. In the sensory evaluation, cheese with 1.0% CS powder showed the highest scores in taste and appearance and good scores in flavor and texture. These results indicate that 1.0% CS is the optimal value for addition to cheese, and cheese containing 1.0% CS shows good physiological properties and reasonably high overall sensory acceptability.

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Changes of Salt Concentration by the Height of Ground Water Table on Disused Saltpan for Golf Course Construction Site (골프코스를 조성할 폐염전 매립지의 지하수위에 따른 토양산도 및 전기전도도 변화)

  • Lee, Dong-Ik;Kim, Ki-Dong;Joo, Young-Kyoo
    • Asian Journal of Turfgrass Science
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    • v.23 no.1
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    • pp.143-150
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    • 2009
  • High salt concentration is one of the most important limit factor on plant growth at a disused saltpan for golf course construction site. The control of salt in soil is definitely required and the monitoring of salt concentration in soil and ground water also required to amend soil physiochemical properties. This research was carried out to monitor the pH and salt concentration changes by the height of ground water. By the physiochemical analysis test, the soil contains a high salt concentration and classified as a slight alkaline clay soil. The height of ground water table changed to 1.3m, 3.3m and 2.8m at dry season(mid-late June, 2005), monsoon season(early-mid July) and after monsoon(late July), respectively. Compare to the average ground level of 2.9m, the ground water was over flooded about OAm at monsoon season. The electrical conductivity(ECe) was measured above $4.0dS{\cdot}m^{-1}$ over all areas and however, some areas showed over $20dS{\cdot}m^{-1}$. During a monsoon season, ECe was lowered to $1.2{\sim}15.0dS{\cdot}m^{-1}$, compared with those of the dry season. Therefore, the interception of the capillary connection between planting layer and ground water which contains high salt concentration should be adapted when golf courses are constructed on disused saltpan. The phytotoxicity caused by salt damage may be controled by the interception of capillary fringe of salt flow to the topsoil profile at the upper layer of the ground water table.

Changes in Chemical Components of Stagnant Water, Germination Rate and Seedling Elongation of Rice Varieties under Different Amount of Barley Straw Mulching (보리짚 피복량에 따른 논물의 화학성분 변화와 벼 발아율 및 유묘신장의 품종간 차이)

  • Cheong, Jin-Il;Kim, Bo-Kyeong;Ha, Ki-Yong;Lee, Jae-Kil;Shin, Hyun-Tak
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.41 no.5
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    • pp.505-513
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    • 1996
  • This study was conducted to investigate the variation of chemical components in stagnant water under different mulching amount of barley straw after combine harvesting and the effect of stagnent water on the germinatidn and seedling elongation at early growth stage in rice. pH was lower in barley straw mulching than non-mulching and decreased with increasing of mulched barley straw but was not different among treatments in stagnant water at 15 days after flooding. Dissolved oxygen decreased with the increasing of mulched barley straw and increased with the passing of time, while saline content increased with the increasing of mulched barley straw, showing significant difference among treatments, was peaked at 15 days after flooding and thereafter, decreased. NH4-N was higher 5 days after flooding with thicker barley straw mulching but was not different at 10 days. N $O_3$-N increased up to 10 to 15 days after flooding and increased with thicker barley straw mulching. Water soluble phosphorus and cation content ( $K^{+}$, $Ca^{2+}$, $Mg^{2+}$)were higher in thicker barley straw mulching and peaked at 10 and 15 days after flooding. Germination rate was decreased by thicker straw mulching and was high in order of medium late, medium and early maturing rice variety. Keumobyeo, Gancheokbyeo, Ilpumbyeo, Dongjinbyeo and Gyehwabyeo showed higher germination rate. Seedling elongation at early growth stage was poorer with increasing of barley. straw mulching. Ilpumbyeo had good seedling elongation in one time amount of barley straw mulching and Shinunbongbyeo, Unjangbyeo, Nonganbyeo and Dongjinbyeo had poorer, in two times.mes.

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