• 한국지반공학회논문집
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• 제20권4호
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• pp.5-13
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• 2004

본 논문에서는 경량기포혼합토의 압축성과 강도 특성에 대해 실험을 통하여 연구하였다. 경량기포혼합토는 재료의 경량화와 압축강도의 증가를 위해 해양준설토에 시멘트와 기포로 구성되어 있다. 이러한 목적을 위하여 초기 함수비, 시멘트 함유율, 실트질 준설토의 혼합을, 구속압조건 등의 다양한 조건에서 준비된 공시체로 일축압축시험 및 삼축압축시험을 수행하였다. 경량기포혼합토의 실험결과, 응력-변형거동과 압축강도는 준설토의 초기 함수비보다 시멘트 함유율에 더 큰 영향을 받는 것으로 나타났다. 또한, 본 연구에서는 초기 함수비, 시멘트 함유율, 기포 함유율을 고려한 정규화계수를 제시하였으며 경량기포혼합토의 압축강도와 정규화 계수와의 유용한 관계를 얻을 수 있었다.

• 한국환경농학회지
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• 제14권3호
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• pp.253-262
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• 1995

중금속이 오염된 밭토양이 그 토양에서 재배된 파잎과 뿌리 및 상치잎, 줄기, 뿌리 시료중 카드뮴, 구리, 납, 아연, 크롬, 니켈, 철, 망간의 중금속 함량을 조사한 결과를 요약하면 다음과 같다. 1. 파와 상치가 고사 또는 생육이 불량한 지점에서 토양중 중금속 함량이 많이 검출되었다. 2. 토양중 중금속함량이 높은 지점에서 식물체중 중금속이 많이 검출되었으며 일반적으로 뿌리, 잎, 줄기의 순서로 많았으나 망간은 잎에서 많이 검출되었다. 3. 토양중 함량과 식물체중 함량간에는 카드뮴, 구리, 아연, 니켈은 고도의 유의성 있는 증가를 가져왔으나 납은 일정한 경향이 없었다. 4. 파와 상치가 정상생육을 하고 있는 지점의 토양중 중금속 함량이 우리나라 일반 밭토양의 평균 함량보다 높았고 식물체에서도 높은 경향이었다.

• 한국환경보건학회지
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• 제39권2호
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• pp.151-158
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• 2013

Objective: This study was carried out to determine the depositional characteristics of pine needles, pine tree bark, moss, and soil, which are used as a passive air sampler (PAS) of atmospheric polychlorinated biphenyls (PCBs). Methods: All four media were sampled from the same site. PCB concentrations were analyzed by GC/MSD, and the lipid contents were measured using the gravimetric method. Results: The total PCB concentration (IUPAC No. 28, 52, 101, 138, 153, 180) was the highest in soil (227.97 pg/g dry), followed by pine needles (71.36 pg/g dry), pine tree bark (44.58 pg/g dry), then moss (21.91 pg/g dry). Pine needles contained the highest lipid contents (21.31 mg/g dry), whereas soil (10.01 mg/g dry), pine tree bark (4.85 mg/g dry), and moss (1.92 mg/g dry) contained less. The concentration of lower-chlorinated PCBs was relatively high in pine needles, pine tree bark and moss, but not in soil. The PCB concentrations were proportional to their lipid contents in pine needles, pine tree bark and moss, but a different trend was revealed in soil. Conclusions: The PCBs concentrations in the media were affected by various factors including atmospheric PCB concentrations, lipid contents, and depositional pathways. However, each of these factors had a varying influence depending on the type of medium.

• 한국환경복원기술학회지
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• 제11권3호
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• pp.129-138
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• 2008

This study was carried out to examine the growth condition of Chionanthus retusa, roadside tree in Cheongyechon (CGC) and to investigate the relationship soil characteristics and tree vitality and chlorophyll contents of it. Growth condition of tree (condition of flower, leaves and branch, % of flowering, height, diameter at breast height, width, vitality and chlorophyll contents) and physiochemical relation item (pH, organic matter, K, Mg, Na, Ca, P) were investigated. The result are as follows : 1. The growth condition of flower, leaves and branch in the left side of CGC is better than the right side since the quantity of sunshine of left side of CGC is much more than the right side. 2. The average pH was alkaline. P and organic contents were much lower than the standards. 3. Tree vitality and chlorophyll contents were bad where were high user density and high buildings, such as 1, 2 area near Jong-gak and jongro 3 ga. Among the physiochemical factors of soil which affect tree vitality, K and P were found to be the main factors. Therefore, in order to improve the growth environment of roadside tree in CGC, it is needed to do periodical soil fertilizing and improve physical characteristics of soil such as, permeability and porosity by soil conditioner.

• Geomechanics and Engineering
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• 제16권4호
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• pp.341-353
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• 2018

A reinforced concrete pedestrian tunnel is constructed under a four-track surface railway. Heavy rainfall and soil exposure to drying lead to soil with different water content throughout the year. A railway is an open utility that is subject to rainfall without control on the quantity of the water on it and when there is a tunnel under a railway, the water content of the soil around the tunnel is very influential. This research shows the effects of change of water content in the soil around a pedestrian tunnel under a four-track surface railway. The pedestrian tunnel and the soil block around the tunnel are modeled in 3D by the FEM and are studied under the vibrations induced by the moving trains on the four-track surface railway for different soil water contents and the effects of the soil water content on the dynamic behavior of the tunnel and the surrounding soil are demonstrated.

• 환경위생공학
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• 제16권4호
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• pp.77-89
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• 2001

The research is intended to evaluate the soil pollution quality of Chungbuk province with Soil Network which is executed every year. The survey executed with Soil Network in 1999 represented that the soil quality of Chungbuk province was relatively good as the average concentrations of contaminants in soil were Cd: 0.146 mg/17g, Cu: 3.143 mgHg, As: 0.636 mg/kg, Hg: 0.012 mg/kg, Pb): 4.505 mg/kg, $Cr^{+6}$ not detected, and the average pH was 6.1. The reckoned soil Pollution score (SPS) of Chungbuk province has been shown much low SPS distribution in the range from 1.6 to 141.7, average 31.0. However, it has been represented relatively high SPS distribution at Chungju, Tanyang, and Chinchon, respectively, It also huts represented high SPS distribution not only at agricultural area and waste area for the Pollution sources but at a paddy field and dry field for land use. The classification of soil pollution class(SPC) based on soil pollution score(SPS) was SPC 1 under 100 of SPS at 212 areas which were 98.6% of total 215 areas and SPC 2 over 100 of SPS at only three area left. There was no area exceeding soil pollution value among the whole Soil Network areas investigated, and the whole average for each items was much lower level th퍼n soil Pollution value was. When the average concentration of heavy metals and the average pH in soil of Chungbuk province are compared with the natural contents of that in Korea, the research is concluded that the average concentration of heavy met is relatively similar to the natural contents of that and the average pH in soil of Chungbuk province is a little higher than the natural contents of that. From this method, soil quality of most of the Soil Network area was estimated to be healthy.

• 아시안잔디학회지
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• 제16권2호
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• pp.65-73
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• 2002

한국의 겨울철 온도 조건하에서 가온에 의한 근권부의 온도조절이 잔디생육과 품질에 미치는 영향을 조사하고 아울러 shoot의 무기성분 함량을 조사한 결과 다음과 같은 결론을 얻었다. 1. 겨울철 근권부의 온도를 20$\pm$2$^{\circ}C$로 유지한 결과 대조구의 잔디는 동해로 인해 생육이 멈춘 반면 온도 처리구에서는 공시된 한지형 잔디(Kentucky bluegrass, perennial ryegrass, tall fescue) 모두에서 녹색이 유지되었으며 예초를 요할 정도의 생육이 계속되었다. 그러나 들잔디의 경우 겨울철 근권부의 온도를 높여주어도 지상부의 생육은 불가능하였다. 2. 온도 처리구에서의 예초량은 tall fescue에서 가장 많았고, 엽록소 함량은 perennial ryegrass에서 가장 높았으며 Kentucky bluegrass는 안토시아닌 함량이 다른 종류에 비하여 높기 때문에 검붉은 색깔을 나타내는 shoot의 수가 많았다. 3. Shoot의 무기양분 함량은 N, P는 토양처리간에 차이가 없었고 K, Ca, Mg는 모래＋peat moss에 비하여 모래＋peat moss＋soil 처리구에서 많은 것으로 나타났다. 4. 근권부의 가온조절은 한국의 겨울철 기온하에서 한지형 잔디의 생육을 도모하고 겨울철 잔디의 녹색을 유지시킬 수 있을 뿐만 아니라 눈 녹음을 촉진시켜 잔디의 이용률을 증진시킬 수 있는 방안으로 판단된다.

• 한국환경농학회:학술대회논문집
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• 한국환경농학회 2011년도 30주년 정기총회 및 국제심포지엄
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• pp.177-187
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• 2011

This study was conducted to determine some physical and chemical properties of the soil and their relationship to spectroscopic-based (visible range) analytical methods while evaluating soil organic matter fractions and soil quality in degraded and non-degraded soils in a wide range of environments. Soil samples were collected from the different landscape positions of cultivated and noncultivated soils, and the latter from the same landscape positions but with different vegetation, at Songco, Lantapan, Bukidnon. The physical and chemical properties of the soils were determined at the SPAL, CMU, Musuan, Bukidnon while the metagenomic properties were determined at the Laboratory of the University of Missourri, Missourri, USA. Bulk density and air dry soil strength values of the soils from the cultivated areas were generally higher than those of the uncultivated areas. Also, soils at the summit generally had lower bulk density and soil strength values than the other landscape positions. Moreover, soils planted to camote (Ipomoea batatas) had higher bulk density and soil strength values compared to soils grown to pepper under the trees. Exchangeable calcium (Ca), magnesium (Mg), and potassium (K) and cation exchange capacity (CEC) of the soils were generally higher in uncultivated areas than those of the cultivated areas. A similar trend was observed for the potassium permanganate ($KMnO_4$)-oxidizable organic C contents determined by spectroscopic method and the total C contents determined by the Walkley-Black method. The $KMnO_4$-oxidizable organic C contents determined by spectroscopic method and the total C contents determined by the Walkley-Black method were closely related ($r=0.631^{**}$). Hence, the former method shows promise in assessing soil quality as it is a rapid test, relatively low cost and can be distributed as a field kit either with a portable spectrometer or with a color chart.

• 한국환경농학회지
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• 제24권1호
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• pp.34-39
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• 2005

양질의 기능성 농산물 생산을 위하여 게르마늄의 농업적 이용에 대한 기초 자료를 제공하고자 경남지역의 토양을 중심으로 지역, 지형, 토양유형 및 토성별 게르마늄 함량과 자연상태에서 재배한 농작물별 게르마늄 함량을 조사하여 그 분포특성을 검토한 결과는 다음과 같다. 토양중 게르마늄 함량을 분석한 결과 경남지역 논 토양 평균 함량은 0.24 mg/kg 이었고, 마산시, 진주시 및 하동군 지역이 0.30 mg/kg 이상으로 높았다. 지형별로는 홍적대지가 0.26 mg/kg으로 약간 높았으나 지형에 따른 큰 차이는 없었다. 토양유형별 게르마늄 함량은 보통답이 0.27 mg/kg으로 사질답과 습답에 비하여 높았으며, 토성별로는 미사질양토가 0.27 mg/kg으로 비교적 높았다. 일반농작물중 게르마늄 함량은 곡류>채소류>과일류 순으로 높았고, 쌀과 보리는 각각 약 68 및 $48{\mu}g/kg$의 게르마늄을 함유하고 있었으며, 단감과 배는 각각 약 11 및 $23{\mu}g/kg$으로 전반적으로 낮은 수준이었다. 채소류중 게르마늄 함량은 엽채류>근채류>과채류 순으로 높았으며 특히 상추와 열무중 게르마늄 함량이 각각 약 62 및 $65{\mu}g/kg$으로서 높았다. 약용작물중 게르마늄 함량은 신선초(Angelica keiskei), 토천궁(Ligusticum chuanxiong), 인삼(Panax ginseng), 삽주(Atractylodes macrocephala), 백지(Angelica dahurica), 맥문동(Liriope platyphylla) 및 도라지(Platycodon grandiflorum)에서 $100{\mu}g/kg$ 이상으로 게르마늄 함량이 높았으며, 선학초(Agrimonia pilosa) 및 일당귀(Angelica acutiloba)의 함량은 각각 37 및 $30{\mu}g/kg$으로 낮았다.

• 한국토양비료학회지
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• 제49권6호
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• pp.677-681
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• 2016

Excessive nitrogen fertilization influences crop yields and quality as well as environmental pollution. In this study, yields, nitrogen use efficiency and free sugar contents of burdock (Arctium lappa L.) were evaluated at different levels of nitrogen fertilization. Nitrogen fertilizer was applied at 5 levels (0, 50, 100, 150, 200%) based on the conventional fertilization ($N=230kg\;ha^{-1}$), and phosphate and potassium fertilizer were treated by conventional P and K fertilization ($P_2O_5-K_2O=140-210kg\;ha^{-1}$) in all plots. The root yields of burdock were the highest in N 100~150% treatment plots. Nitrogen use efficiency and nitrogen recovery decreased from over N 150% treatment. Nitrogen uptake of root was greater than that of shoot in N 50~200% treatments. Fructose contents in root were inversely proportional to the level of nitrogen fertilization. As considering nitrogen recovery and root quality, economical burdock yield was obtained in N $230kg\;ha^{-1}$.