• Proceedings of the Korea Water Resources Association Conference
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• 2022.05a
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• pp.306-306
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• 2022

2015년부터 2019년까지 우리나라에서는 평균 18,521 ha의 경작지에 가뭄피해가 발생하였다. 이 중 평균 11,260 ha는 밭으로 피해의 60% 이상이 밭에서 발생하는 것으로 나타났다. 밭 가뭄 피해는 2016년과 2018년에 크게 발생하였으며, 제주에서 가장 큰 피해가 발생하였다. 또한 강원도, 충청남도의 여러 지역에서 지속적인 피해가 나타났다. 농업 가뭄을 대응하기 위하여 저수지와 지하수 관정 등을 활용하고 있지만, 밭에 대한 구체적이고 체계적인 가뭄 대응 방안은 미비하다. 따라서 본 연구에서는 밭 가뭄에 대한 취약성을 지역별로 평가하고 이를 기반으로 우선 관리지역을 선정하는 방안을 검토하였다. 밭 가뭄 취약성 평가에는 위협 요인, 피해 요인, 해소 요인을 평가 기준을 설정하였다. 밭 가뭄에 대한 위협 요인은 토양 수분량의 정도로 제시할 수 있으며 본 연구에서는 1995년부터 2014년까지 20년간의 강수량, 증발산량 등의 기상 및 토양 자료를 활용하여 분석하였다. 피해 요인은 피해를 입는 밭이 대상으로 행정구역 단위로 평가를 수행함에 따라 행정구역별 밭 비율을 산정하여 활용하였다. 해소 요인은 가뭄 피해를 감소시킬 수 있는 활동을 반영하는 평가 기준으로서 본 연구에서는 저수지와 지하수관정 등 밭 가뭄 저감에 활용할 수 있는 요소를 반영하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.17 no.1
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• pp.1-6
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• 1984

Soils in Cheju Island, derived mostly from volcanic ashes, were collected for chemical analysis to determine the effect of land utilization pattern on soil chemical characteristics. The coastal area has long been used for intensive farming and some of the mid-mountain region were recently reclaimed for agricultural crop production. The cation exchange capacity and the organic matter in the soils increased in the order of coastal area < mid-mountain belt < upper mountain area, while pH, base saturation, available phosphorus and exchangeable bases decreased with the elevation. Generally, the organic matter, the cation exchange capacity and the exchangeable bases of the Cheju soils were found to be considerably higher than the Korean mainland soils. However, the base saturation and the available phosphorus were far below the mainland average. The ratio of monovalent basic cations to total exchangeable bases showed the highest in the soils of the mountain belts and the lowest in the coastal area soils. These data suggest that a higher soil pH in the coastal area as compared to the mountainous slopes has resulted not from the sea water but from continuous application of alkaline fertilizers and times.

• Journal of Wetlands Research
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• v.21 no.2
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• pp.163-172
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• 2019

The USLE P factor is a factor that varies depending on how croplands are managed and cultivated. Previous studies tend to overestimate the amount of soil loss because the factor was estimated from the slope of the watershed rather than the estimate of each cultivated land. In addition, the accuracy of estimating the soil loss is decreasing due to the fact that the factor is calculated without considering various conditions of cultivated land defined by Wishmeier and Smith. In order to overcome these problems, the Ministry of Environment (MOE) has proposed to establish the topsoil notification and calculate the P factor according to the cultivation methods (e.g., tillage system, support practice). However, it is required to apply the conditions proposed in the United States to domestic circumstances as it is causing uncertainties. Thus, this study selected the watersheds where soil loss was serious (Haean, Jaun, Banbyeoncheon), measured the actual slopes and slope lengths, and examined the crop, tillage systems, and support practice for each cultivated land. The P factors were recalculated considering the actual conditions of cultivated land and compared to the factors proposed by the previous studies (MOE). As the result of the study, the P factors calculated based on the previous studies were 0.8 ~ 1.0 in three watersheds. On the other hand, it is confirmed that there is a significant difference between the factors notified by MOE and estimated by reflecting the topography and cultivation methods in this study. Therefore, it is considered that the research for developing the cultivation conditions to calculate the P factor suitable for the domestic environment should be continuously carried out.

• Korean Journal of Environmental Biology
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• v.27 no.3
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• pp.272-278
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• 2009

To investigate abundance of soil organisms in the ginseng cultivation, we have selected 6 different cultivated lands in Jinan-gun, Jeollabuk-do. The microarthropods were assessed on the basis of 3,101 individuals collected between April and November 2008. The taxonomic composition and abundance of microarthropods were as follows: Acari 44.9%, Collembola 50.1% and others 5.0%. Density increased at the cast and 4 year point, and the population of microarthropods was high in April and May, but low in July and August. Acari/Collembola ratio was approximately 0.90%. There was no correlation between soil factors and microarthropods. The density of soil actinomyces represented a monthly average $0.3{\sim}0.9{\times}10^6\;cfu\;g^{-1}$, and fungi tended to increase and decrease regularity at each spots, where highest decrease was observed in August and September. The density of bacteria was $1.1{\sim}9.6{\times}10^6\;cfu\;g^{-1}$ in each period and those in June and August were much higher than after August. The distribution of fluorescent Pseudomonas showed regular tendency in early survey periods but did not appear in significant numbers after July.

• Korean Journal of Soil Science and Fertilizer
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• v.31 no.4
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• pp.414-419
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• 1998

The contribution of soil organic matter on the soil surface charge characteristic of paddy and upland soils weathered from granite or limestone was evaluated. The surface charge characteristics of the soils with and without soil organic matter by pre-treatment with hydrogen peroxide was determined at pH 3.5~9.0 range using the ion adsorption method. Regardless of soil organic matter removal, the soil surface negative charge increased linearly by the increase of pH with high statistical significance at all kinds of soils. Here, the differential increasement of soil surface negative charge by pH inclease, dCEC/dpH, was proposed as the parameter of pH dependency of the soil surface charge. The dCEC/dpH of soils with organic matter was in the range of 0.91~4.59, while it was dramatically decreased to the range 0.16~1.91 by the removal of organic matter. The soil surface charge derived from soil organic matter ranged from 15% to 82% to the total amount of surface charge. The magnitude of surface charge carried by 1% of soil organic matter showed considerable differences between soils from 0.22 to $5.03cmol^+\;kg^{-1}$. The effect of soil organic matte on the dCEC/dpH was higher in paddy soils with high oxalic acid extractable Fe than upland soils.

• Korean Journal of Environmental Agriculture
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• v.10 no.1
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• pp.1-10
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• 1991

The object of this stduy was to investigate the pollution of Pb in paddy field soil with different distance from roadside and to find out the relationship between the ratio of chemical fractions of total Pb and soil characteristics. Lead from automobiles is exhausted as particulates composed primarily of halide compounds (PbBrCl, $PbBr_2$, $PbCl_2$). The samples of soil were collected directly from the paddy fields with different distance from the roadside of highway and expressway which are located in Kyungpook province. A sequential extraction procedure was used to fractionate Pb in paddy field soil into the disignated forms of water soluable, exchangeable, organically bounded, carbonate, sulfide, and residual Pb. Results obtained are summerized as follows. 1. The content of Pb in paddy field soil was the highest in Chungdo, 30.0 ppm, the lowest in Koryung, 14.8 ppm, and the total average content was 21.9 ppm. The effect of traffic volume was not clear, but a slight difference according to the order of opened year of roads was showed. 2. The effect of distance from roadside was not clear. The content of Pb in paddy field soil with different distance from roadside was 22.2 ppm within l0m, 22.1 ppm in 10∼30m, 22.2 ppm in 30∼50m. and 21.3 ppm beyond 50m. 3. The distribution of Pb fractions in soil showed a wide difference depending on soil properties. The average content of exchangeable. organically bounded, carbonate, sulfide, and residual Pb was 8.6%, 33.6%, 29.8%, 21.5%, and 6.7%, of total Pb in the soil, respectively. 4. The content of organically bounded Pb in soil showed highly positive correlation with organic matter and CEC, while the content of exchangeable Pb was highly negative correlation. 5. With higher soil organic matter and CEC, organically bounded Pb fraction tend to be higher but exchangeable Pb fraction tend to be lower. Other forms of Pb showed no difference with soil organic matter contend and CEC. The distribution of Pb fraction related to CEC showed similiar tendency with that of organic matter content.

• Proceedings of the Korea Water Resources Association Conference
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• 2011.05a
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• pp.190-194
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• 2011

경포호 주변환경은 논, 밭 등의 경작지나 녹지와 같은 투수지표면과 대단위 주택단지나 도로, 상업지구, 공장시설과 같은 불투수지표면으로 구성되어 있어 SWAT 모형의 적용에 적합하다. GIS와 연계된 ArcSWAT모형을 적용하기 위하여 지형자료를 구축하고, 송정배수로 유역의 기상 및 우량 관측소를 고려하여 수문 및 기상관측자료를 입력하였다. 그리고, 소유역으로 세분화한 후 토양특성과 토지이용에 따른 모의를 실시하였고, 이를 위해 소유역내 수문학적 반응단위별로 유출, 유사 및 비점오염발생을 평가하는데 이용되는 HRU를 구축하여 활용하였다. 송정배수로는 제1배수로와 제2배수로로 구성되어있으며, 제2배수로의 유입부에 주변 아파트단지의 하수관에서 직접적으로 오염물질이 유입되어 수질오염이 심각하며, 점원과 비점원오염이 산재해있기 때문에 본 연구에서는 유출 및 수질모의가 가능한 SWAT모형을 이용하여 대상지점의 유출과 수질을 모의하였으며, 그 결과를 바탕으로 수질오염을 저감할 수 있는 방안을 제시하였다.

• The Korean Journal of Pesticide Science
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• v.9 no.1
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• pp.102-107
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• 2005

To select microorganisms that exhibit antifungal activity against the fungal pathogens of pepper, Phytophthora capsici and Colletotrichum acutatum, soil samples from a forest and natural fields of Gajang-Dong, Sangju-city were tested in vitro and in vivo. Streptomyces griseofuscus 200401 was finally selected throughout antifungal activity test with dual culture, culture broth, and fruits. For the identification of the strain, nucleotide sequences of 16S rDNA and whole cell fatty acids were analyzed. It is like that the strain 200401 may be a novel biological control agent that can reduce application of chemical fungicides to control late blight and anthracnose on pepper.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.803-806
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• 2008

LEACHN is the computer simulation model which can be used to simulate field-scale N transformations and movement and has three organic pools (plant residue, manure, and soil humus), three inorganic pools (urea, nitrate and ammonium) and plant. Pot experiment operated May to October in 2004. LEACHN simulated the nitrogen movement and transformation in soil using method of PEST and trial and error.

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2002.02a
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• pp.507-513
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• 2002

본 연구에서는 정밀농업 구현을 위해 필수 불가결의 요소인 데이터베이스 구축의 필요성에 착안하여 공간 및 속성 데이터 구축 알고리즘의 설계와 데이터베이스를 구성하는 테이블의 스키마 설계를 통해 공간 및 비공간 데이터를 구축하고 구축된 데이터베이스와의 통신을 통해 농작업 기계의 위치에 따른 토양 속성값을 추출해 내는 과정을 보임으로써 의사결정 지원시스템으로서의 기능을 시뮬레이션을 통해 제시하였다. 연구에 사용된 공간 및 비공간 데이터 구축에 있어서의 수작업은 작업자로 하여금 노동 소모적인 작업을 요구하므로 차후의 연구에 있어 보다 자동화되고 개선된 알고리즘의 개발이 요구된다. 또한 구축되어야 하는 경작지의 규모가 커지고 비공간 데이터의 양이 많아지게 되면 데이터베이스내의 검색 성능 향상에 대한 고찰 또한 병행되어야 할 것으로 판단된다.