• Korean Journal of Soil Science and Fertilizer
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• v.16 no.4
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• pp.311-317
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• 1983

These studies were carried out to investigate the effects of rice straw on the leaching of chemical constituents in paddy soil. Rice plants were cultured in paddy soil to which rice straw was applied and then chemical properties of percolated water were analysed. The results were as follows. The leaching of calcium and magnesium was affected by rice straw application in the early stages of plant growth and by rice root activity in the late stages. The application of the straw promoted the reduction of the soil followed by increasing the leaching of iron and manganese. The leaching of potassium, ammonium-nitrogen and chloride was not due to the application of rice straw and the leaching of carbon dioxide increased with the application of rice straw, at the same time chemical properties seemed to be affected by rice root activity. Generally, cation and anion leached in the percolated water were equivalent. Calcium, magnesium, Fe as cation and $HCO_3$, $SO_4{^{-2}}$ as anion were important constituents in the percolated water from paddy soil.

• Korean Journal of Soil Science and Fertilizer
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• v.4 no.2
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• pp.187-192
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• 1971

This paper deals mainly with the genesis and classification of the Jeonnam series. These soils have brown to dark brown silt loam and silty clay loam A horizon(strong brown or reddish brown where eroded). Argillic B horizons are dominantly red or yellowish red silty clay loam to silty clay with moderately developed subangular blocky structure and with thin clay cutans on the ped faces. The C horizons are strongly and very deeply weathered strong brown, yellowish brown, pale brown and reddish yellow silty clay loam and sandy loam granitic saprolite. Content of clay increases with depth to a maximum between 100cm. Percolating water seems to be responsible for transportation and oriented deposition of clay. Chemically, soil reaction is strongly acid to medium acid throughout the profile. The content of organic matter is 1 to 2 percent, and decreases regularly with depth. Base saturation is low, based on amount of extractable cations. Characterisltically the Jeonnam series are similar to Red-Yellow Podzolic soils of the United States and are similar to Red-Yellow soils of the Japan. In the writer's opinion the Jeonnam soils are classified as Red Yellow soils. According to USDA 7th approximation, this soil can be classified as Typic Hapludults and in the FAO/UNESCO World Soil Map as Helvic Acrisols.

• Journal of the Korea Organic Resources Recycling Association
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• v.8 no.1
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• pp.77-82
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• 2000

Seven constructed and three natural tidal flats were compared to evaluate state-of- the-art of creation and restoration technology for tidal flats. parameters studied were physico-chemical and biological characteristics of soils and rate of respiration. The natural tidal flats had higher contents of silts, nitrogen and organic matter compared to the constructed ones. The natural ones had reductive Bone below 2 cm whereas the constructed ones had oxidative zone from the surface to below 20 cm. The bacterial population in the soil of the constructed tidal flats was one to two magnitudes lower than that in the natural ones. Biomass of macrobenthos and microbial respiration rate, however, were not different significantly between the natural and the constructed tidal flats. The purification capacity by diatom+bacterial+meiobenthos and macrobenthos in the constructed tidal flats was higher than that in the natural ones due to deeper permeable layer for purification in the constructed tidal flats. There was an exceptional constructed tidal flat with similar physico-chemical and biological characteristics to natural ones. Shearing stress to the surface of the tidal flat by the flow of seawater was as low as that of natural ones. These hydraulic conditions seemed to be a controlling factor on structures and functions of tidal flats. The control of hydraulic condition seemed to be one of the most important factors to create natural-like tidal flats.

• Journal of the Korean Association of Geographic Information Studies
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• v.22 no.3
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• pp.107-119
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• 2019

As the development of ICT and integration technology, many changes and innovations in agriculture field are implemented. The agricultural sector has shifted from a traditional industry to a new industrial form called the 6th industry combined with various advanced technologies such as ICT and IT. Various approaches have been attempted to analyze and predict crops based on spatial information. In particular, a variety of research has been carried out recently for crop cultivation and smart farms using drones. The goal of this study was to establish an agricultural drought monitoring system using drones to produce scientific and objective indicators of drought. A soil moisture sensor was installed in the drought area and checked the actual soil moisture. The soil moisture data was used by the reference value to compare and analyze the temperature and NDVI established by drones. The soil temperature by the drone thermal image sensor and the NDVI by the drone hyperspectral was analyzed the correlation between crop condition and soil moisture in study area. To verify this, the actual soil moisture was calculated using the soil moisture measurement sensor installed in the target area and compared with the drone performance. This study using drone drought monitoring system may enhance to promote the crop data and to save time and economy.

• Proceedings of the Plant Resources Society of Korea Conference
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• 2022.09a
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• pp.41-41
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• 2022

제주 내 크게 6개 지역에 흩어져 분포하고 있는 곶자왈은 화산활동으로 형성되었으며 제주 산림생물자원의 46%가 분포하여 생물종다양성이 매우 높은 것으로 알려져 있다. 곶자왈은 자갈과 바위로 이루어져 있으며 토양이 적게 발달하여 건조에 직면할 가능성이 크다. 본 연구는 곶자왈에서 서식하는 멸종위기종이자 산림청에서 희귀식물로 지정한 개가시나무(Quercus gilva)와 같은 속이면서 공존하고 있는 종가시나무(Quercus glauca)의 건조 내성에 대한 반응을 알아보고자 실내에서 생리 반응을 연구하였다. 온도(22±2.94℃)와 토양 양분(10%)은 자생지의 값을 기준으로 처리하였으며 수분 처리는 토양을 채운 화분에 물이 화분 밑으로 새어나가기 직전까지 포장용수량 700mL를 공급한 후 27일간 단수하였다. 단수기간에 수분함량의 변화는 토양수분함량측정기(Watch Dog)를 설치하여 데이터를 수집하였다. 항목은 토양수분함량에 따른 광합성률, 증산률, 수분이용효율, 기공전도도, Fv/Fm, Fo, Fm, 엽록소함량을 측정하였다. 토양수분함량은 25, 27일째를 제외한 기간에 개가시나무가 종가시나무보다 높았다. 광합성률은 27일째를 제외한 기간에 개가시나무가 종가시나무보다 높았다. 증산률은 4, 5, 11, 14, 25, 27일째에 개가시나무가 종가시나무보다 낮았다. 수분이용효율은 13일째를 제외한 기간에 개가시나무가 종가시나무보다 높았다. 기공전도도는 3, 9일째에 개가시나무가 종가시나무보다 높았다. Fv/Fm은 22, 27일째를 제외한 기간에 개가시나무가 종가시나무보다 높았다. Fo은 3, 14일째를 제외한 기간에 개가시나무가 종가시나무보다 높았다. Fm과 엽록소함량은 기간에 개가시나무가 종가시나무보다 높았다. 이와 같은 실험 결과로 보았을 때 개가시나무가 종가시나무보다 건조 내성에 강한 것으로 판단된다.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.331-337
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• 2023

Physiological disorders in pear fruit are mainly caused by problems during the growing season, such as lack of calcium in the soil, poor drainage, low porosity, vigorous pruning, and excessive fruiting. In this study, soil physicochemical properties and leaf characteristics were analyzed in pear orchards in four regions of Korea where chlorosis symptoms occurred to determine the causes of chlorosis. The color of chlorotic leaves was diagnosed using the naked eye or SPAD and Hunter values. The soil of the chlorotic orchard had a significantly higher soil pH than that of the regular orchard. Although adequate soil depth was not significantly associated with chlorosis, combined with over-fertilization of the soil with lime, it could potentially impair plant iron uptake. Chlorotic leaves had significantly lower iron and calcium contents and significantly higher magnesium contents than those of regular leaves. Therefore, the intensive occurrence of chlorosis during secondary shoot development around June and July when it is hot and humid may be due to impaired iron and calcium absorption, leading to physiological disorders. To solve this problem, avoiding the over-application of lime and applying foliar fertilizers containing chelated iron is recommended.

• Korean Journal of Soil Science and Fertilizer
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• v.19 no.4
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• pp.275-282
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• 1986

A series of studies on the properties of clayey terrace soils distributed at the inland (Yeongcheon) and coastal (Yeongjil) regions in Yeongnam district was carried out. On the base of the facts found and already reported about the macro morphological features as well as on pedological characters in micro scale, physicochemical properties, mineralogical characteristics etc., the present study dealt with soil genesis and tried to classify the soils for reasonable use and managements. 1. Although the both regions belonged to "Mesic" soil temperature regime and "red and yellow earths" areas of "Thornthwaite" pedo-climatic diagram, climatic indices as a soil forming factor indicate that the coastal Yeongil had milder than the inland Yeongcheon. 2. All the terrace soils had developed soil profiles with an "Argrllic B". Upyeong soils in Yeongil region had "Argillans" even in the "II B horizons" that possibly be "Paleo-argillic". 3. The bisequum profiles of Bancheon in Yeongcheon and Upyeong in Yeongil revealed that they were developed on Late Mesozoic shale and on semiconsolidated Tertiary deposits respectively, therefore the overlying clayey terrace deposits were assumed to be originated from the Early Quaternary deposits, Diluvium. 4. To supplement the Soil Taxonomy of USDA, the terrace soils with different degrees of gleyzation were classified as follows; Deogpyeong and Hwadong soils which have less than 50cm of paddified gley horizons (redness less than 0.5) in the upper part of the profiles by artificial surface irrigation, tentatively classified into "Anthrepiaquic Hapludalfs" and the Geugrag soils that have more than 50cm of paddified gley horizons within 1.2m of the profiles, into "Anthr-aquic Ochraqualfs" while the Upyeong soils that had greyish mottles in subsoils by natural ground water remain as an "Aquic Hapludalfs" the same as present. The Bancheon soils with free mottles are into "Typic Hapludalfs" as used at present.

• Economic and Environmental Geology
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• v.37 no.4
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• pp.383-389
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• 2004

Understanding flow pattern of water and solute in subsurface is essential for the reduction and prevention of contamination of soil and groundwater and for the investigation and remediation of contaminated site. The objective of this study is to examine the infiltration pattern in a soil developed from the Jurassic granite using (Brilliant Blue FCF $C_{37}H_{34}N_{2}Na_{2}O_{9}S_{3}$), the nonfluorescent and nontoxic food dye. All image processing was conducted using geographic image processing software, ER Mapper, Version 6.2. The dye coverage was determined by counting the stained pixels in the photographs (80${\times}$80cm, 80TEX>${\times}$5cm) for the vertical and horizontal view. A homogeneous matrix flow occurred in the A horizon with weak, medium granular structure and fingering at the interface of finer-textured A horizon and coarser-textured C horizon. Pegmatitic vein originated from the granite and plant root in C horizon induced preferential flow.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2018.05a
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• pp.341-343
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• 2018

Agriculture has the longest history in many industries and is directly or indirectly linked to human development. However, recently agriculture in Korea has difficulties in farm management due to the decrease of rural population, aging of society, increase of material costs, and climate change on the Korean peninsula. Smart farms using ICT are proposed as an alternative to solve these problems. Smart farms manage the temperature and water supply facilities of farms through various sensors, but there is a limit to the delicate management of crops. Therefore, in this paper, unlike the conventional moisture sensor, the water supply is varied according to the depth of the soil, thereby realizing an optimized environment for plant growth.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 1997.11a
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• pp.145-159
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• 1997

Cheju Island is the most attractive resort area in Korea for its exotic landscape, natural beauty, and traditional culture which is quite different from that of the mainland. Until now, most of the recreational facilities and accomodations have been constructed along the coastal areas. Recently, mid-mountain area has been under very heavy development pressure because it is suitable for new sites for tourism facilities and the land price in the coastal area is very high. The mid-mountain area is the land located 200-600m above the sea level. It is a major source of water supply for the island and has exotic scenic beauty, which cannot be found in mainland but it is the area very vulnerable to water pollution Therefore, it is very important to manage this area based on the concept of environmentally sound and sustainable development in order to meet ever increasing demand for the land development The purposes of this project are: 1) to establish Geographic Information System for the whole island, 2)to formulate environmentally sound landuse plat However, There has been accuracy of the original map, defining criteria of analysis, updating of the data were identified for future tasks to be studied.