• 농업과학연구
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• 제49권2호
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• pp.239-247
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• 2022

The physico-chemical properties of agricultural soil are factors that affect crop productivity and soil fertility. In Korea, agricultural environment change surveys have been conducted every four years since 1999. The purpose of this study is to investigate the status and changes in the physico-chemical properties of agricultural soil in Chungcheongnam-do. Samples were collected from the exact location of the aforementioned environment survey, and environmental variables (land use, type of crop cultivated) were investigated in relation to the samples. Soil collection was conducted using a core sampler and a single gouge auger. The bulk density of the soil generally increased up to a depth of sampling of 40 cm but decreased thereafter to a depth of 60 cm. Additionally, the bulk density was highest in the upland soil case and stood at 1.59 g·cm^-3, while the lowest value of 1.52 g·cm^-3 was obtained from orchard soil samples. Conversely, the porosity and moisture gradually decreased at soil depths of 0 - 40 cm and increased at depths of 40 - 60 cm. Most of the soil chemical properties generally decreased with an increase the soil depth from 0 to 70 cm, but electrical conductivity (EC) increased up to a depth of 40 cm. Therefore, it is judged that it is necessary to lower the bulk density by supplying organic matter for agricultural land in Chungcheongnam-do.

• The Korean Journal of Ecology
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• 제22권1호
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• pp.1-6
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• 1999

공단지역과 비공단지역의 삼림에서 토양미소절지동물의 개체군 밀도, 수직 및 계절적 분포 그리고 토양산도와의 관계를 비교 조사하였다. 조사지역 토양에서 관찰·분리된 토양미소절지동물은 총 3950개체 이었으며, 그 중 제일 많은 개체수는 거미강으로 총 1,918개체로 전체 의 약 48.5%를 차지하였다. 체장이 가장 길은 곳은 칠갑산의 낙엽수림이며(113.6 mm), 가장 짧은 곳은 대산지역의 낙엽활엽수림지역이었다(46.8 mm). 토양소동물의 개체수는 봄에서 여름에 걸쳐 증가하였고, 가을과 겨울로 갈수록 감소하는 추세를 보였다. 계절에 따른 수직분포상황은 전체적으로 봄에는 중층부에서 많이 나타났고 여름과 가을은 상층부에서 그리고 겨울은 하층부에 많이 분포하는 것으로 나타났다. 종다양도지수는 비공단지역(1.02)이 공단지역(0.73)보다 높았고 가장 높은 곳은 계룡산 침엽수림의 중층(5∼10 cm)에서 1.60이었고, 가장 낮은 곳은 대산 낙엽수림의 심층(10∼15 cm)에서 0.24로 나타났다.

• 자원환경지질
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• 제30권4호
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• pp.371-377
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• 1997

This paper presents the geophysical applications to the environmenml problem in an abandoned mine area. We would like to focus our attention on the mapping of the soil contamination and the detection of the buried mine tailings. For mapping the soil contamination. measurements of both in-situ magnetic susceptibility (k) and terrain conductivity were carried out. In-situ magnetic susceptibilities of the contaminated soil due to the acid mine drainage show higher values than those of the uncontaminated area. However. those data do not show the correlation with the degree of the soil contamination observed on the surface. The least-squares fitted formula obtained with the measured insitu magnetic susceptibilities is $k=4.8207{\times}W^{0.6332}$, where W is the $Fe^{+2}$ weight percentage. This weight gives most effect to magnetic susceptibility of the soil. Lateral variations of the soil contamination in the shallow subsurface can be detected by the electrical conductivity distributions from EM induction survey. TDIP (Time Domain Induced Polarization) and EM induction surveys were conducted to detect the buried mine tailings. From the results of TDIP, the spatial zone, which shows high chargeability-low resistivity, is interpreted as the buried mine tailings. Therefore, it is concluded that it is possible to discriminate the spatial zone from the uncontaminated ground.

• 한국환경복원기술학회지
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• 제10권6호
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• pp.139-151
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• 2007

To protect the surface of ground-cutting slopes and ground-raised slopes and to recover environment-friendly slopes at the national road expansion construction between Gamchon and Yaechon, test-construction work was done using several modes of hydro-seeding measures to select a suitable construction method through the field survey; the results were as follows : As a result of survey on physio-chemical characteristics of soil, the average soil inclination on ground-raised slopes was from 4.73 mm to 5.37 mm; the average soil acidity was from pH 6.47 to 6.73; the average soil humidity was within the scope of 0.57~1.70 %,; the average soil inclination on ground-cutting slopes was 9.17~10.43mm; the average soil acidity was pH 6.67~6.77 and the average soil humidity was within the scope of 0.53~1.27 %; considered overall, they showed generally satisfactory base materials for plant breeding. As a result of the number of sprouting individuals, the average sprouting number of individuals on test spots executed by Coir net with Seed spray construction methods and the average number of sprouting individuals on other test spots executed by furrow-digging with Seed spray and Straw mat-mulching measures were 1,172 number of per square meter and 970 number of per square meter respectively; thus they showed higher numerical value comparing with other test spots. Likewise, the average number of sprouting individuals on test spots of the ground-cutting slopes executed by Coir net with Seed spray method and the average number of sprouting individuals on other test spot executed by furrow-digger with Seed spray and Straw mat-mulching measures were found to be 1,107 number of per square meter and 1,105 number of per square meter respectively, whose numerical value showed rather higher other test spots. As a result of a survey on living plants' breeding index [dried weight], the weight in dried state on test spots executed by Coir net with Seed spray method and other test spots executed by furrow-digger with Seed spray and Straw mat-mulching measures on both ground-raised and ground-cutting slopes was found to be higher and showed similar characteristics statistically. As a result of survey on the surface-covering degree of ground-raised slopes, nine weeks after test construction, test spots executed by Coir net with Seed spray method and other test spots executed by furrow-digger with Seed spray and Straw mat-mulching measures showed commonly more than 70% of surface-covering degree, but other test spots showed only below 35% of surface covering degree; especially in case of test spots by Verdvol seed spray measures, they showed 10% of the lowest surface-covering. Surface-covering degree on the test spot of ground-cutting slopes nine weeks after test construction showed more than 75% both executed by Coir net with Seed spray construction method and executed by furrow-digger with Seed spray and Straw mat-mulching measures. As a result of survey on appearing plants on the test spots, there dominates Eragrostis curvula both on ground-raised slopes and on ground-cutting slopes with other seeding plant life's lower breeding and there appear intruders, such as Setaria viridis Beauv, Digitaria sanguinalis Scop, and Chenopodium album var.centrorubrum Makino. As for water-borne excavation and soil's washing-away on the slopes, there happened less washing-away and water-borne excavation with good breeding of plant life on test spots executed both by Coir net with Seed spray construction method and by furrow-digger with Seed spray and Straw mat-mulching measures, but there happened much more soil's washing-away along with water-home excavation at the test spot executed by Seed spray with measures. After the research results of test construction sites are examined overall, it's presumed that furrow-digger with Seed spray and Straw mat-mulching measures [interval between lines is 40cm, 5cm in depth] will be preferred to prevent erosion and water-home excavation of slopes located within the construction sites.

• 한국방재안전학회논문집
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• 제14권3호
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• pp.17-27
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• 2021

본 연구에서는 6개의 기계학습 기법들을 활용하여 2019년과 2020년 전국 땅밀림 현장조사 결과를 기반으로 땅밀림 위험지역을 A부터 C까지 3개 등급(A등급: 위험, B등급: 보통, C등급: 양호)으로 구분할 수 있는 분류모형을 구축하고, 분류 정확도를 비교·분석한다. 기계학습 기법으로는 K-Nearest Neighbor, Support Vector Machine, Logistic Regression, Decision Tree, Random Forest, Extreme Gradient Boosting 총 6개를 적용하였다. 분류 정확도 분석결과, 6개의 기법 모두 0.9 이상의 우수한 정확도를 보여주었다. 수치형 자료를 학습에 적용한 경우가, 문자형 자료를 학습한 모형보다 우수한 성능을 나타냈으며, 현장조사 평가점수 자료군(C1~C4) 보다는 전문가의견이 반영된 평가점수 자료군(R1~R4)으로 학습한 모형이 정확도가 높은 것으로 분석되었다. 특히, 직접징후와 간접징후 정보를 학습에 반영한 경우가 예측정확도가 높게 나타났다. 향후 땅밀림 현장조사 자료가 지속적으로 확보될 경우, 본 연구에서 활용한 기계학습기법은 땅밀림 분류를 위한 도구로 활용이 가능할 것으로 판단된다.

• 환경영향평가
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• 제9권4호
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• pp.339-348
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• 2000

This study was conducted to investigate the distribution pattern of plants on the streamside of Goggyochun, and to survey the distribution of heavy metal-contaminated soils and plants. A total of 11 survey sites were selected along the Goggyochun during the period of between June and September 1999. The wet land plants were composed of 44 species. The most frequently occurring species in the study sites were Rumex crispus, Persicaria hydropiper, Cyperus amuricus and Setaria viridis, and among them the Humulus japonicus, Erigeron canadensis and Phragnites communis species were dominants of the community. Analysis of soil properties showed that organic matter and clay contents were higher in the upstream region while sand content was higher in the downstream region. The pH and the organic matter contents of soils were at range of 6.70-9.94 and 2.39-15.16% respectively. The average contents of Pb and Cd in soils were 11.96mg/kg and 1.64mg/kg respectively, and these values were higher as compared with those of ordinary soil in Korea. The average contents of Zn and Pb in Persicaria hydropiper were 8.30mg/kg and 7.38mg/kg respectively, and these values were higher than other plants. The distribution of heavy metals in plants varied in accordance with the species regardless of the sites.

• 한국환경복원기술학회지
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• 제26권4호
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• pp.1-16
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• 2023

The purpose of this study is to understand the vegetation structure of the Corylopsis coreana habitats in South Korea and their correlation with environmental factors, in order to provide basic data for preparing conservation. A total of 40 vegetation survey plots were established in around Southern region, Gangwon-do and Gyeonggi-do Province. The cluster analysis revealed four distinct clusters: Quercus mongolica-Pinus densiflora (QmPd), Castanea crenata (Cc), Quercus mongolica (Qm), and Pinus koraiensis (Pk). Among them, the QmPd cluster was selected as the representative community. Soil texture analysis that most areas consisted of loamy soil and were distributed on the northern aspects. The plantation, represented by Pk, exhibited a high content of exchangeable aluminum (5.227±0.342 mg/kg), suggesting the need for soil improvement and monitoring in these habitats. The canopy openness (forest gap) ranged from 11% to 21%, indicating a relatively closed canopy in many survey plots. Non-metric multidimensional scaling analysis indicated heterogeneous species composition between the QmPd cluster and the Pk cluster (total R² = 0.608).

• Nuclear Engineering and Technology
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• 제50권8호
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• pp.1289-1297
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• 2018

Preliminary surface soil Derived Concentration Guideline Levels (DCGLs) were derived conforming to the Multi-Agency Radiation Site Survey and Investigation Manual (MARSSIM) procedure for the site release and reuse of Kori Unit 1 in Korea. Based on the decommissioning experiences of the U.S. nuclear power plants, a suite of residual radionuclides was determined, and uncertainties contributed to the resultant dose by the input parameters were quantified via the sensitivity analysis of parameters. The peak of the mean dose was obtained via the probabilistic analysis of the RESRAD (RESidual RADioactivity)-ONSITE code. Consequently, $DCGL_w$ of Kori Unit 1 in accordance with two scenarios, industrial worker and residential farmer scenario, were derived and the results were compared respectively with other NPPs. It could be used as a basic guideline for establishing regulatory standards for reuse planning, designing the site characterization surveys and implementing final status survey (FSS).

• 한국토양비료학회지
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• 제45권4호
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• pp.475-483
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• 2012

최근 농경지의 급격한 감소와 더불어 도시화, 경지정리, 도로공사 및 혁신도시 건설 등으로 토지이용의 변화가 심하게 발생되고 있다. 특히, 토지이용 변화심화지역인 경기도 고양시, 충청남도 천안시, 강원도 원주시를 대상으로 토지 이용변화실태, 토양특성변화양상, 토양도수정내용 및 기업도시 등으로 편입되는 지역의 토양환경분석을 하였다. 이에 대한 결과를 요약하면 다음과 같다. 1. 우리나라의 경지면적 (2011년)은 2009년대비 17.3 ha가 감소되었다. 논의 경우 24.2 ha가 감소되었으나, 밭의 경우에는 7.0 ha가 증가하였다. 2. 논의 면적 감소사유로는 논밭전환 (20.7 ha) > 공공시설 (3.2) ${\geq}$ 건물건축 (3.2) > 유휴지 (1.3) > 기타 (0.9) 순이며, 밭 면적의 증가원인은 논밭전환 (20.7 ha) > 개간 (4.5) > 복구 (0.3) 순이었다. 논밭전환의 이유는 논농사에서 농가소득이 높은 밭작물 내지 시설작물로 전환하는 것으로 생각된다. 3. 토지이용변화가 심한 해당시군의 농경지감소 (논, 밭, 과수)는 밭토양조사 (1995~1999) 당시와 비교 (2011년)할 때 고양시는 1,466 ha, 천안시 9,708, 원주시 6,980 ha가 감소되었으며, 1999년 대비 45%~25%의 농경지가 급격히 감소되었다. 4. 환경부 토지이용피복도의 통계자료 활용성을 검토하기 위해 농식품부 통계자료와 비교시 지목별로 큰 차이가 있었다. 따라서, 추후 면밀한 검토를 통하여 활용 방안을 마련해야 할 것이다. 5. 원주시의 토양정보 변경내용을 보면 곡간지의 일부 논토양이 밭 또는 과수원으로 토지이용이 변경되었으며, 배수등급의 경우 도로건설 등으로 인해 저습화되는 등 해당 토양의 일부 특성정보가 변경되었다. 특히, 논토양의 경우 시설재배지, 밭, 과수원, 휴경, 성토화 등으로 토지 이용의 변화가 심하였다. 6. 원주시 혁신도시에 편입되는 논토양은 급지가 떨어지는 3~4급지가 대부분으로 3급지 70.8%, 4급지 29.2%이었다. 밭토양 역시 4급지가 88.7%인 토양으로 우량 급지가 혁신도시 건설에 속하지는 않았다. 앞으로 우량농경지 보전을 위해 제도적 장치의 마련이 필요하다고 생각한다.

• 한국환경복원기술학회지
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• 제15권5호
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• pp.115-127
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• 2012

This study was conducted on the measurement of soil hardness through a hardness testing machine in slopes of natural environments and artificial environments which is generally known as slope revegetation. The soil hardness as one of physicochemical soil properties is significantly associated with plant growth. Although another studies related to the slope revegetation was focused on herbaceous plants, studies related to soil properties for arbor appearance is lack. It was focused on the correlation analysis between the soil hardness and the plant appearance. the results were as follows : The higher the soil hardness is, the less the appearance of plants is as a result of survey. Species appearing in the high levels of the soil hardness represented mugwort and grass. The levels of the soil hardness in the slope of natural environments was good environmental conditions with various plants in the range of 6 to 12mm. The levels of the soil hardness in the slope revegetation was in the 6.88-30mm range. The soil hardness below 21mm showed a variety of plants with arbors and herbaceous plants, whereas it above 21mm represented a monotonous style of plant structure including Artemisia princeps, Lolium perenne, Poa pratensis L and Setaria viridis. The result of the correlation analysis between the soil hardness and the plant appearance was negatively correlated with justifiable significance levels. The result of a logistic regression analysis for tree appearance was statistically proved when the numerical value of the soil hardness is lower.