• 대한토목학회논문집
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• 제10권4호
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• pp.133-140
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• 1990

약액주입시 사질지반에서 발생하는 수압파쇄의 발생기구를 해명하기 위하여 여러가지 고결사에 대해 많은 주입시험을 행하여 할렬압($P{_f}^{\prime}$)과 구속압(${\sigma}_3^{\prime}$), 고결사의 인장강도(${\sigma}_t$), 투수계수(k)등과 상관관계를 구하였다.

• 한국농공학회지
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• 제43권1호
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• pp.102-105
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• 2001

This study has been done to investigate the characteristics of the wall materials of a earthen house ; the core-wall of a wood-frame house and the mud-wall of a all-wall house. A series of tests is carried out to study the physical properties of wall materials which are picked from existing earthen houses. The core-wall materials are composed of sandy soil or clayey soil with low plasticity. The mud-wall materials are sandy soil with well compaction effect. It is confirmed that the wall materials are common soils which are easily picked from the residential quarter.

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.457-458
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• 2001

Reproductive and life history patterns of marine amphipods are influenced by a variety of biotic and abiotic factors. Those factors may vary on local scales or along geographic patterns and result local or geographic variations in reproduction and life history. Although many studies in life history of amphipods were carried out at various habitats, limited information on the life history and reproduction at a shallow sandy shore 〈 1 m depth is available (Bear and Moore, 1996). (omitted)

• 한국어업기술학회:학술대회논문집
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• 한국어업기술학회 2001년도 춘계 수산관련학회 공동학술대회발표요지집
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• pp.479-480
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• 2001

Harpacticoid copepods are one of the most important components in the benthic meiofaunal community. In spite of their numerical significance the study of harpacticoids in Korea, as distinct from meiofauna in general (Kim et al., 1998, 2000a, b), has been limited. During the course of investigation on ecological significance of harpacticoids in the intertidal sandy shore, a new species of the genus Rhizothrix was determined and described here. (omitted)

• 농업과학연구
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• 제41권4호
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• pp.369-377
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• 2014

This study was carried out to evaluate the effect of rice husk (RHB) and food waste biochar (FWB) on upland soil with sandy loam texture, in terms of physico-chemical analysis, lettuce seed germination test, and orgainc carbon leaching experiment. RHB and FWB had different physico-chemical properties each other. Carbon to nitrogen ratio (C/N ratio) of RHB was 32, showing two times higher than that of FWB. FWB had high salt and heavy metal content, compared to RHB. This is probably due to different ingredients and production processing between two biochars each other. Results of germination test with Lettuce showed lower germination rate when FWB was applied because of higher salt concentration compared to control and RHB. Organic carbon leaching test using saturated soil column (${\Phi}75{\times}h75mm$) with $10MT\;ha^{-1}$ biochar application rate, showed higher saturated hydraulic conductivity in rice husk biochar treatment column, compared to control and food waste biochar treatment. The highest total organic carbon concentration in column effluent was lower than those in both of rice husk biochar and food waste biochar, whereas the differences was negligible after 9 pore volumes of effluent. Consequently, biochars from byproducts such as rice husk and food waste in sandy loam textured upland soil could enhance a buffer function such as reduction of leaching from soil, but the harmful ingredient to crops such as high salt and heavy metals could limit the agricultural use of biochars.

• 농업과학연구
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• 제41권4호
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• pp.399-404
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• 2014

Soil moisture is an important factor for the availability and circulation of nutrients in arable soil. The purpose of this study was to set thresholds moisture content on soil nitrate concentration in the solution for real-time diagnosis. Sandy loam, silt loam, and sandy loam was filled with $1.2g\;cm^{-3}$ at Wagner pots, 0, 100, and $200mg\;L^{-1}$ of $KNO_3$ was saturated. Nitrate in standard solution was recovered about 95% by passing the porous cup. Nitrate concentrations in sampling of soil solution were examined by using a porous cup. The soil solution was higher in accordance with sandy loam> silt loam> clay loam, limited water filled pore space for sampling soil solution was 33.7, 56.4, and 62.2%, respectively. Nitrate concentration in the soil solution was negligible at sandy loam and silt loam during sampling periods, which was decreased about 50~82% in clay loam compared to the initial $NO_3$-N concentration in the saturated $KNO_3$ solution. Over limitation of soil solution sampling, soil EC and $NO_3$-N content were increased with the saturated $NO_3$-N concentration, regardless of soil texture (p<0.05). Conclusively, soil solution by using a porous cup was possible, regardless of the soil texture, which was useful for the diagnosis in nitrate concentration of soil solution. However, because nitrate concentration of soil solution in a clay loam changes, it was necessary for careful attention in order to take advantage for the real-time diagnosis of nitrogen management in soil.

• 유기물자원화
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• 제15권1호
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• pp.149-158
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• 2007

토양중 유박의 온도(10, 20, $30^{\circ}C$) 및 수분변화 (양토 : 포장용 수량의 40, 50, 60, 70%, 사양토 : 포장용수량의 50, 60, 70, 80%)에 따른 무기화정도를 검토하기 위해 토양과 피마자유박, 대두박, 탈지강을 혼합하여 실내항온배양을 30일간 실시하여 무기태 질소를 측정하였다. 또한 PVC파이프로 컬럼을 제작하여 실외 포장에 토양컬럼을 설치하여 30일 후 토양깊이에 따른 무기화를 조사하였으며 실내 및 실외배양에 사용된 토양은 사양토와 양토로 이들 두 토양간의 무기태질소의 생성량을 조사하였다. 피마자박, 대두박 및 탈지강을 토양에 혼합하여 실내항온배양을 실시한 결과 배양온도가 높고 수분함량이 높을수록 무기태 질소의 생성량이 증가되었으며 양토보다 사양토에서 무기태 질소의 생성량이 높았다. 한편 토양컬럼 실험결과 토심에 따른 무기태 질소의 생성량은 토심이 깊어짐에 따라 감소하였으며 실내항온배양과 마찬가지로 사양토가 양토보다 무기태 질소의 생성량이 높았다.

• 한국토양비료학회지
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• 제14권2호
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• pp.64-69
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• 1981

사질토양(砂質土壤)의 투수계수(透水係數)에 대한 물성공극(生物孔隙)의 영향(影響)을 구명(究明)하기 위하여 하성충적지(河成沖積地) 분포(分布)하고 있는 본양사양토(本良砂壤土) ( Coarse loamy over sandy, mixed, mesic family of Typic Udifluvents)를 사용(使用)하여 생물공극(生物孔隙)의 분포(分布)와 투수계수(透水係數)와의 관계를 조사(調査)한 결과(結果)는 다음과 같다. 1. 투수계수(透水係數)는 당량투과표면적(當量透過表面積)과 고도(高度)의 정(正)의 상관(相關)이 있으나 가밀도와는 부(負)의 상관(相關)이 있었다. 2. 투수계수(透水係數)에 대한 생물공극(生物孔隙) 영향(影響)은 심토(心土)에서 크지만 인위적(人馬的) 교란(攪亂)이 심한 작토층(作土層) 토립(土粒)이 매우 큰 기층(基層)의 사토(砂土)에서는 적었다. 3. 가밀도는 생물공극(生物孔隙) 양(量)과 당량(當量) 투수표면적(透水表面積)에 유의적(有意的)인 회귀관계(回歸關係)를 나타내었다. 4. 생물공극(生物孔隙)의 분포(分布)와 가밀도는 토심간(土深間), 동일층위내(同一層位內)의 지점간(地點間)에 변이(變異)가 크다.

• 식물병연구
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• 제9권2호
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• pp.64-67
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• 2003

배추 뿌리혹병을 방제하기 위하여 상토의 종류와 농약 병용처리에 대한 효과를 조사한 결과 온실시험에서 피트 모스, 바로커 상토에 육묘한 배추에서의 발병도가 48.3, 54.2%에 비해 황토, 마사토 상토에 육묘한 배추에서는 발병도가 10.8, 18.7%이었고 포장시험에서는 피트모스 상토 75.7%, 바로커 36.6$, 마사토21.7%, 황토 14.1% 순이었다. 후루설파마이드 분제를 토양에 혼화처리하였을때는 봄재배에서 피트모스 상토에서는 발병도 4.5%에 비해 황토 상토에서는 0.4%이었고 가을재배에서는 10.1, 5.7%이었다. 이상의 결과에서 피트모스, 바로커 상토보다 황토, 마사토 상토를 사용하고 후루설파마이드 분제로 약제처리하면 뿌리혹병 방제에 효과적일 것으로 생각된다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.1-11
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• 2013

The actively soil pollution by the toxic heavy-metals like the arsenic, cadmium, lead due to the industrialization and economic activity. The uses the electrokinetic remediation of contaminated soil has many researches against the fine soil having a small size in the on going. However, it is the actual condition which the research result that is not effective due to the low surface charge of the particle and high permeability shows in the electrokinetic remediation in comparison with the fine soil in the case of the sandy soil in which the particle size is large. In this research, the electrokinetic remediation and ultrasonic wave fetch strategy is compound applied against the sandy soil polluted by the arsenic, cadmium, and lead removal efficiency of the sandy soil through the comparison with the existing electrokinetic remediation tries to be evaluated. First of all, desorption of contaminants in soil by ultrasonic extraction in the Pre-Test conducted to see desorption effective 5~15%. After that, By conducted Batch-Test results frequency output century 200 Khz, reaction time 30 min, contaminated soil used in experiment was 500 g. Removal efficiency of arsenic, cadmium, lead are 25.55%, 8.01%, 34.90%. But, As, Cd, Pb remediation efficiency less than 1% in EK1(control group).