• Korean Journal of Environment and Ecology
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• v.34 no.5
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• pp.413-424
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• 2020

Environmental policies and industry practices have recently seen a gradual paradigm shift from reactive management to proactive prevention of environmental impacts. Accordingly, preventive conservation policies are carried out to address the increasing value of protecting soils and soil functions as resources are limited. To propose a direction for future soil erosion research, we analyzed domestic and international research trends of soil erosion, based on journal papers retrieved from the Web of Science databases over the last decade, using VOSviewer for keyword co-occurrence analysis. The results showed that the number of publications on soil erosion per land area in Korea ranked high worldwide. In particular, studies on the soil erosion control were found to account for a more significant proportion than other countries. The active ongoing studies on soil erosion in Korea indicate that the country has recognized the severity of soil erosion resulting from climate, topography, and land use. However, the number of keywords found in the studies on the soil erosion control in Korea was relatively smaller than those found at the international level, indicating the need to diversify and expand the study subjects. In particular, studies on the soil erosion process and the related physical and chemical soil properties are necessary to find the fundamental solutions to soil erosion problems.

• Korean Journal of Soil Science and Fertilizer
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• v.33 no.3
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• pp.175-181
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• 2000

This study was carried out to investigate the change of soil physical properties in long-term fertilized paddy soils with a Fine silty family of Typic Halpaqueps (Pyeongtaeg series). Treatments fertilized consisted of no fertilizer, compost, NPK, NPK+compost for thirty one years and of NPK+silicate for seventeen years. Water stable aggregate and degree of aggregate stability, which were higher in surface-soil than sub-soil, were high in order of NPK + compost > NPK + silicate > compost > NPK > no fertilizer plot. The ratio of aggregate larger than 0.5mm was high at compost and silicate plots but that smaller than 0.5mm was high at no fertilizer and NPK plots. And this aggregate stability showed negative correlation with soil hardness and bulk density ; positive correlation with sedimentation volume of soils in water. Sedimentation volume of soils in water was a little higher in surface-soil than sub-soil and in wet soil than dry soil, respectively. Pore space ratio and water retention capacity of soils were the most increased by the application of compost and not affected by silicate as in cases of liquid limit and plastic limit. Ignition loss of soils was high in order of NPK + compost > compost > NPK + silicate > NPK > no fertilizer plot. And field shattering ratio of soil mass smaller than 25.4mm was relatively high in NPK + compost, compost, and silicate plots.

• Korean Journal of Plant Resources
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• v.22 no.1
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• pp.102-110
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• 2009

This study examined the halophyte community and soil analysis according to habitat in representative 18 salt marshes of southern and western coasts of Korea from July 2006 to April 2008 and suggested basic materials for vegetational restoration of these aras. First, the survey area was classified into coastal and estuarine marshes. Then, the coastal marshes were classified into clay marsh, sand gravel marsh, and sand marsh, and the esturarine marshes, into salt swamp and estuary marsh. Major plant communities according to habitat pattern were Phragmites communis, Carex scabrifolia, and Suaeda japonica community in the clay marsh; Phragmites communis, Zoysia sinica, Carex scabrifolia, Salicornia herbacea, Artemisia fukudo, Suaeda martima community in the sand gravel marsh; Elymus mollis, Carex kobomugi, and Vitex rotundifolia community in the sand mars; Phragmites communis, Zoysia sinica, Suaeda martima, and Carex scabrifolia community in the salt swamp, and Suaeda japonica, Phragmites communis, Carex scabrifolia, and Suaeda asparagoides community in the estuary marsh. The soil environment of halophyte community area showed a difference to soil and halophyte community according to habitat characteristics of halophyte. Thus, to restore salt mashes in the coast area, it is advantageous for the stable settlement, germination, and growth of halophyte to grasp physical and physicochemical characteristics of habitat soil in the salt marshes, to select halophyte suitable to these habitat conditions, and to expand gradually in the natural vegetation area after transplantation.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.3
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• pp.304-314
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• 2010

This study was carried out to find out potential use of ochre as an agent to reduce phosphorus content in water. Ochre is a by-product from treatment of acid mine drainage (AMD) which is composed mostly of $Fe_2O_3$, $Fe_2O_3{\cdot}H_2O$, $FeO{\cdot}OH$ and $Fe(OH)_3$. Three ochre samples (ochre-H, ochre-D and ochre-S) were collected from three treatment facilities in Gangwon province. Physico-chemical characteristics of three ochre samples including pH, electrical conductivity, total phosphorus, available phosphorus, particle size distribution were analyzed. Scanning electron microscopy (SEM) energy dispersive spectroscopy (EDS), X-ray diffraction (XRD) and X-ray fluorescence (XRF) analysis were also carried out. In addition, experiments for phosphorus removal from water was performed. Calcium content of ochre-H was higher than that of ochre-D and ochre-S, whereas iron content of ochre-H was lower than that of ochre-D and ochre-S. All the phosphorus in water up to maximum 191,411 mg $kg^{-1}$ per unit mass of ochre was removed with ochre-H. Ochre has immense potential as an agent to reduce phosphorus content in water.

• Journal of Korean Society of Forest Science
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• v.89 no.1
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• pp.24-32
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• 2000

We investigated the patterns of soil horizon evolution and its water distribution on three different forest stands covered with Larix leptolepis, Pinus koraiensis, and Qercus mongolica on the Experimental Forest of Kyunghee University, located in Kwangju, Kyunggi-Do. Compared to the properties of depths of O and A horizons evolved on the Pinus koraiensis stand, the depths of O and A horizons on the forest stands of Larix leptolepis and Qercus mongolica were shallower, indicating that the soil horizon were deeply influenced by geographical characteristics, its erosive and sedimentary distinction, vegetation cover and its population density. And the bulk densities of the sites selected were lower in the high slope gradient than that in the lower slope gradient at the same depth of soil profile. Therefore, the changes of the soil bulk densities were closely related to the soil organic matter and the vertical transport of soil particle throughout soil depths. On the other hand, the bulk density and organic matter content in soil can influence the water transport phenomena, resulting in decrease of the hydraulic conductivity as the increase in the bulk density, while the organic matter can not affect the hydraulic conductivity on the soil surface layer. For a rainfall infiltration characteristics from a lysimeter experiment established on the stand of Larix leptolepis, the bulk density and slope gradient strongly influenced the vertical transport of water, as well as the lateral movement of rainfall. Conclusively, the characteristics of water movement and distribution in the forest stand can be determined not by the geographical factor such as slope gradient but also by the bulk density and organic matter content remained in soils.

• Proceedings of the Korea Water Resources Association Conference
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• 2008.05a
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• pp.738-743
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• 2008

최근 기상이변으로 인한 돌발홍수의 빈번한 발생으로 인해 신속하고 정량적인 강우예측의 필요성이 대두되고 있으며 강우의 거동을 실시간으로 관측하여 예측이 가능한 강우레이더의 활용성이 높아지고 있다. 또한, 1Km 해상도의 격자형으로 제공되는 강우레이더를 효과적으로 활용하기 위해 격자단위의 분석이 가능한 분포형 수문모형의 활용이 증가하고 있다. 본 연구를 위한 선행연구로 배영혜 등(2007)은 레이더 강우와 물리적 기반의 분포형 모형인 $Vflo^{TM}$을 이용하여 임진강 유역에 대한 강우-유출 모의를 실시하였으며 분포형 모형의 입력 자료로 활용된 임진강 유역의 공간자료는 임진강 유역조사 성과 및 GIS/RS를 자료를 이용하여 구축하였다. 배영혜 등(2007)이 모의한 임진강 유역의 홍수 유출 모의 결과 모의치와 관측치 사이의 첨두값은 일치하나 지체 시간의 차이가 발생하는 것으로 나타났다. 이러한 오차의 원인을 파악하기 위해 북한의 하천과 연결되지 않은 임진강 영중지점을 대상으로 홍수 유출 모의를 실시한 결과 지상 강우계를 이용한 레이더 강우의 보정 유무보다는 GIS 수문매개변수의 불확실성이 오차에 큰 영향을 주는 것으로 나타났으며 특히 토양분류 체계가 상이하고 현시성이 결여된 토양도의 활용이 수리전도도를 비롯한 토양 매개변수에 불확실성을 초래하여 첨두 유량과 지체시간 등에 영향을 준 것으로 파악되었다. 본 연구에서는 유역면적의 약 2/3가 미계측 지역인 임진강 유역의 지리적 특성과 현지조사가 필수적인 토양도의 재구축이 현실적으로 어렵다는 점을 고려하여 상대적으로 단순한 가 분포형(Quasi-distributed) 수문 모형인 ModClark 모형을 이용하여 2006년 7월 사상에 대하여 홍수 유출 모의를 실시하였으며 그 결과를 선행연구를 통해 모의한 $Vflo^{TM}$ 모형의 유출 모의 결과와 비교하였다.

• Korean Journal of Agricultural Science
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• v.5 no.2
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• pp.127-135
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• 1978

For improvement and new design of tillage equipments, indoor test is very useful and more desirable than outdoor because the experiment of outdoor is very difficult and its cost is expensive. This study was carried out to determine the physical properties of artificial soil suitable for the indoor test with the soil bin manufactured at the workshop of the Dept. of Agricultural Machinery Engineering. The artificial soil being studied was made with very similarity to the natural soil of the experimental plots of Chungnam National University, and it consist of 39.35 percent, by weight of bentonite and 48.10 percent of sand with 12.55 percent of SAE 10W oil. The results are summarized as follows: 1. Bulk density increased with increasing number of rolling, and its relationship could be expressed. $y=1.073200+0.070780x-0.002263x^2$ where, y=bulk density ($g/cm^3$), x=number of rolling. These results could be explained that the effect of rolling velocity on the bulk density was not singnificant in the range of 4.5~10.4 em/sec. 2. The absolute soil hardness depended directly upon number of rolling, and their relationship could be expressed by the equation. $y=37.74(0.64 +0.17x-0.0054x^2)/(3.36-0.17x-0.0054x^2)^3$. where, y=absolute soil hardness($kg/cm^3$), x=number of rolling. 3. Relationship between the bulk density and absolute soil hardness could be expressed by the equation; $y=37.74(2.46x-2.02)/(6.02-2.46x)^3$. where, y=absolute soil hardness, x=bulk density. 4. The cohesion and the angle of internal friction of artificial soil were increased with increasing its bulk density. According to the cohesion and angle of internal friction, at the range of 1.60~1.75 ($g/cm^3$) of bulk density, this artificial soil was similar with sandy loam of 29.5% moisture content of natural soil. 5. Sliding-fricfion coefficient of steel plate on the artificial soil was 0.3~0.4 and rubber plate on it is 0.64~0.72. Those values were very similar with those of natural soil being studies by many others.

• Korean Journal of Poultry Science
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• v.33 no.1
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• pp.65-80
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• 2006

Ash amendment to manure holds potential as a method to neutralize manure for reducing odor and reduce phosphorus (P) solubility in runoff from fields where manure has been applied. This review focuses on the literature published about ash characteristics and their environmental uses. There is no uniform physico-chemical definition of the selected ashes (coal fly ash-CFA, wood ash-WA, and rice hull ash-RHA) used in various studies. These ashes vary greatly in their acidity (pH<6.0) or alkalinity (pH>12.5) based on the conditions at which they were farmed and the composition of the ash source. CFA amendment to manure reduced manure-P solubility and application of CFA amended manure to agricultural soils is a method to improve water quality WA may prove to be a valuable manure odor control amendment since WA contains a high level of carbon. A major biomass source is rice hull (husk) which provides an ash source (RHA). The .ice hull and RHA are sources of silica, compromising about 20% and 60%, respectively. So far research has been directed at the use of CFA, WA and RHA as soil amendments, but there is potential use of these materials as manure additives to sequester P and reduce odors.

• Journal of Bio-Environment Control
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• v.11 no.4
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• pp.199-204
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• 2002

To overcome a decrease of Korean ginseng production caused by successive cropping, we have tried to develop a nutrient culture system for Korean ginseng production. For determining the optimal substrate, mixture of sand and TKS-2 (S＋T), peatmoss (P), reused rockwool (RR), and granular rockwool (GR) were investigated. The overall physico-chemical properties of RR fell into the reported optimal range for the ginseng cultivation. However, bulk density of S＋T was a little higher than that of soil in Korean ginseng fields. The top fresh weight of the ginseng was high in RR and S＋T substrates. The root fresh and dry weights in the RR were remarkably greater than that in the conventional soil (CS) of Korean ginseng fields. In terms of ginseng quality, the vitamin C content of ginseng root in nutrient culture was higher than that in CS. However, the contents of crude saponin and total ginsenosides in ginseng between in the nutrient culture and in the soil culture did not show any significant differences.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.17 no.1
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• pp.76-81
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• 2024

Recently, agricultural methods are changing from experience-based agriculture to data-based agriculture. Changes in agricultural production due to the 4th Industrial Revolution are largely occurring in three areas: smart sensing and monitoring, smart analysis and planning, and smart control. In order to realize open-field smart agriculture, information on the physical and chemical properties of soil is essential. Conventional physicochemical measurements are conducted in a laboratory after collecting samples, which consumes a lot of cost, labor, and time, so they are quickly measured in the field. Measurement technology that can do this is urgently needed. In addition, a soil analysis system that can be carried and moved by the measurer and used in Korea's rice fields, fields, and facility houses is needed. To solve this problem, our goal is to develop and commercialize software that can collect soil samples and analyze the information. In this study, basic soil composition measurement was conducted using soil composition measurement sensors consisting of hardness measurement and electrode sensors. Through future research, we plan to develop a system that applies soil sampling using a CCD camera, ultrasonic sensor, and sampler. Therefore, we implemented a sensor and soil analysis UI that can measure and analyze the soil condition in real time, such as hardness measurement display using a load cell and moisture, PH, and EC measurement display using conductivity.