• 한국수자원학회논문집
• /
• 제38권5호
• /
• pp.345-354
• /
• 2005

국내 산지사면에서의 토양수분의 시공간적 분포를 파악하기 위한 동축 다중체계의 TDR (Time Domain Reflectometry)을 설마천 유역의 범륜사 사면에 구축하고 토양수분 집중 모니터링을 실시하였다. 대상사면을 정밀 측량하여 정밀 수치지형모형(Digital Elevation Model)을 구축하고 흐름분배알고리즘에 적용하여 측정지점을 선정하였고 역 측량을 통한 효율적인 측정 체계를 구축하였다. 2003년 11월중의 380시간 동안의 집중 모니터링을 통한 토양수분 자료를 확보하였다. 확보된 토양수분자료는 대상사면의 지형분석을 통해 구분된 상부, 중부, 하부사면의 변화특성을 보여주고 있다. 물리적 수문 모형의 구성과정에서 중요한 의미를 부여하는 토양수분 실측치와의 유의성을 논의하였다.

• 한국환경복원기술학회지
• /
• 제11권5호
• /
• pp.60-71
• /
• 2008

Through analyzing the specific physicochemical alterations in depth-based soil at reclaimed dredging area, the baseline data were provided for developing the reclaimed dredging area as natural landscape planting sites and ecological-landscape sites based on the soil improvement technology. There was no physical disturbance for 15 to 20 years in Gwangyang Bay reclaimed dredging area after reclamation. Physicochemical examinations of the soil were performed based on the vertical depth. Results of physicochemical analysis such as pH, electric conductivity, total salt contents, silt, clay contents, available phosphorus, calcium, magnesium, sodium, chlorine, and sodium-adsorption ratio showed increasing patterns with the depth while total organic contents, total nitrogen, and sand showed decreasing patterns. Potassium as an exchangeable cation, showed similar distribution patterns between the shallow and deep soil. This result strongly implied that long-term exposure to natural rainfall in reclaimed dredging area altered soil characteristics related to salinity. This research demonstrated that there were no remarkable differences in physicochemical characteristics at soil depth and groundwater table height, suggesting a baseline data for developing reclaimed dredging area. Additional investigation is required for different reclaimed dredging areas. Also, additional monitoring and examination are need on plant communities and time variable alteration in the soil to test the feasibility of reclaimed dredging areas as natural landscape planting sites and ecological-landscape sites.

• 한국토양비료학회지
• /
• 제6권1호
• /
• pp.1-8
• /
• 1973

호남야산(湖南野山) 지역(地域)에 분포(分布)하고있는 화강암풍화잔적층(花崗岩風化殘積層)에 발달(發達)된 적황색토중(赤黃色土中) 조립질(粗粒質)인 예산통(禮山統)과 세립질(細粒質)인 송정통(松汀統)에 대(對)한 형태적(形態的) 이화학적(理化學的) 특성(特性)에 관(關)하여 조사(調査)한 결과(結果)를 요약(要約)하면 다음과 같다. 1. 형태적(形態的) 특성(特性)에 있어서 예산통(禮山統)의 경우 표토(表土)(A층(層))는 진갈색(眞褐色) 내지(乃至) 갈색(褐色)의 사양토(砂壤土)이며 심토(心土)(B층(層))는 황적색(黃赤色) 내지(乃至) 적색(赤色)의 사질식양토(砂質埴壤土) 내지(乃至) 사양토(砂壤土)이고 구조(構造)의 발달(發達)이 매우 약(弱)하다. 송정통(松汀統)의 경우 표토(表土) (A층(層))은 침식(浸蝕)에 의(依)하여 심토부위(心土部位)가 노출(露出)된 암적색(暗赤色)의 미사질식양토(微砂質埴壤土)이며 심토(心土) (B층(層))는 적색(赤色)의 미사질식양토(微砂質埴壤土)이고 구조표면(構造表面)에 엷은 점토피막(粘土皮膜)이 형성(形成)되여 있다. 기층(基層)은 양토양(兩土壤) 공(共)히 심(甚)하게 풍화(風化)된 화강암(花崗岩)의 잔적모재(殘積母材)이며 토양(土壤)의 깊이는 50~100m이다. 2. 이화학적(理化學的) 특성(特性)에 있어는 예산통(禮山統)의 경우 점토함량(粘土含量)은 17%내외(內外), 산성(酸性) (표토(表土)6.0심토(心土) 4.5~5.0)이고 유기물(有機物) 함량(含量)은 표토(表土)에서 1.8% 심토(心土)에서 0.1~0.4%이며 유효인산은 40ppm. 염기치환용량(鹽基置煥容量)은 4~8me/100gr로써 매우 낮으나 염기포화도(鹽基飽和度)는 표토(表土)에서 57.8% 심토(心土)에서 46.3%에서 46.3%로서 중용(中庸)이다. 송정통(松汀統)의 경우 점토함량(粘土含量)은 30~40% 내외(內外), 산성(酸性)(5.7~6.0)이고 유기물(有機物) 함량(含量)은 표토(表土)에서 1.25%, 심토(心土)에서 0.1~0.4이며 유효인산은 4ppm. 염기치환용량(鹽基置換容量)은 표토(表土)에서 6.2me/100gr. 심토(心土)에서 2.6me/100gr로써 매우 낮음과 동시(同時) 염기포화도(鹽基飽和度)는 표토(表土)에서 28% 심토(心土)에서 16~23%로서 낮다. 3. 예산통(禮山統) 및 송정통(松汀統)은 온난습윤기후하(溫暖濕潤氣候下)에서 생성(生成)되며 적황색토(赤黃色土)라고 분류(分類) 명명(命名)할수 있으며 미(美) 농무성(農務省) 7차(次) 시안(試案)에 의(依)하면 예산통(禮山統)은 Inceptisols 중(中) Typic Dystrochrepths에 송정통(松汀統)은 Ulti sols 중(中) Typic Hapludults에 속(屬)한다.

• 한국토양비료학회지
• /
• 제43권1호
• /
• pp.25-35
• /
• 2010

약간 경사가 있고 침식 가능성이 높은 배나무 과수원 포장에서 2가지 종류의 제초제를 처리하여 유거수와 토양침식의 변화를 관찰하였다 : (1)발아 전 처리 제초제 - Glyphosate; (2)발아 후 처리 제초제 - Paraquat. 조사지 포자의 고도는 125 m 경사도는 5.5% ~ 10.2%의 분포를 보였다. 한편 조사기간인 2006년 6월과 2008년 11월 사이의 강우 횟수는 각각 47, 52, 52회로 조사되었다. 정상적인 침투율은 보통 잡초가 모두 제거된 맨땅에서 증가하지만 제초제가 처리된 땅에서는 감소했다. 대조구에서 유거수는 항상 제초제를 처리한 땅과 맨땅에서 보다 더 적었다. 같은 강우강도에서 유거수는 대조구, glyphosate 그리고 paraquat 순으로 증가하였다. 강우의 강도가 센 경우에 유거수 차이는 조사 첫해에 약간 더 높았다. 토양 유실은 연구기간 3년 동안 약간씩 다르나 조립질 토양보다 미세질토양에서 유실이 더 많았다. 하지만 토양유실은 총강우량과 유거수와는 밀접한 연관이 없는 것으로 조사되었다. 동일 강우강도에서 토양침식률은 대조구, glyphosate, paraquat 그리고 glyphosate가 처리된 맨땅 순으로 증가하였다. 상대적으로 30 mm $day^{-1}$보다 낮은 강우량에서 제초제 처리와 상관없이 토양유실에 미치는 영향은 차이가 없었다. 결과적으로 토양침식에서 중요한 요인은 강우강도이다.

• Journal of Microbiology and Biotechnology
• /
• 제30권11호
• /
• pp.1688-1696
• /
• 2020

Soil physical and chemical characteristics, soil potential denitrification rates (PDR), community composition and nirK-, nirS- and nosZ-encoding denitrifiers were studied by using MiSeq sequencing, quantitative polymerase chain reaction (qPCR), and terminal restriction fragment polymorphism (T-RFLP) technologies base on short-term (5-year) tillage field experiment. The experiment included four tillage treatments: conventional tillage with crop residue incorporation (CT), rotary tillage with crop residue incorporation (RT), no-tillage with crop residue retention (NT), and rotary tillage with crop residue removed as control (RTO). The results indicated that soil organic carbon, total nitrogen and NH₄⁺-N contents were increased with CT, RT and NT treatments. Compared with RTO treatment, the copies number of nirK, nirS and nosZ in paddy soil with CT, RT and NT treatments were significantly increased. The principal coordinate analysis indicated that tillage management and crop residue returning management were the most and the second important factors for the change of denitrifying bacteria community, respectively. Meanwhile, this study indicated that activity and community composition of denitrifiers with CT, RT and NT treatments were increased, compared with RTO treatment. This result showed that nirK, nirS and nosZ-type denitrifiers communities in crop residue applied soil had higher species diversity compared with crop residue removed soil, and denitrifying bacteria community composition were dominated by Gammaproteobacteria, Deltaproteobacteria, and Betaproteobacteria. Therefore, it is a beneficial practice to increase soil PDR level, abundance and community composition of nitrogen-functional soil microorganism by combined application of tillage with crop residue management.

• 한국환경복원기술학회지
• /
• 제4권1호
• /
• pp.16-23
• /
• 2001

This study was conducted to analyse the relation between physical characteristics of soil surface and wild plants occurrence. Lots of natural occurrence on loamy soil and a little of natural occurrence on perlite. Those were used to observe the wild plants occurrence through the duration. Natural occurrence of wild plants were observed on uniform sand, perlite, loamy soil and 2cms loamy soil layer above the perlite. Uniform sand was compared with different height of drain ditch. The results of analysis were as followed. 1. Wild plants germinated on the uniform perlite layer, they did not grow larger. Because water in large pores of perlite surface drained rapidly and evaporated easily, therefore surface remained low moisture contents. 2. A lot of weed grew on 2cms loamy layer on perlite which stratified above the perlite layer. Because perlite had plenty of soil moisture and soil moisture moved easily from perlite to loamy soil layer. 3. Uniform loamy soil had similar occurrence on the uniform perlite. It was nearly same at surface moisture distribution but lower than layered loamy soil on perlite, and the vertical distributions at soil moisture was totally lower than 2cms loamy soil layer on perlite. 4. Wild plants were grew on uniform sand on different height of drain ditch. In this case, much more wild plants were grew on which had more higher drainage ditch. The number of wild plants occurred when it was affected by soil surface moisture, drain ditch and natural occurrence of wild plants. This could be controlled by layered soil at surface moisture. Therefore weed occurrence can control in planting ground, where soil layer would not be disturbed.

• 한국지반환경공학회 논문집
• /
• 제1권1호
• /
• pp.43-50
• /
• 2000

본 논문은 폐스티로폴과 현장발생토를 활용하여 경량성토재로서의 특성을 파악하고자 하는데 목적이 있다. 폐스티로폴 입자는 가볍고 단열성이 좋으며 진동차단효과도 우수하기 때문에 경량성토재로서의 활용이 가능하다. 특히 스티로폴은 1996년 재활용품목으로 선정되어 토공재료로서의 적합성만 확인된다면 체계적인 공급이 가능하다. 따라서 본 논문에서는 폐스티로폴 입자와 현장발생토를 혼합한 후 혼합비와 고화재의 투입량을 변화시켜가며 다짐시험, 일축압축시험, 정수위 투수시험, CBR 시험, 실체현미경분석을 실시하였으며, 그 결과 폐스티로폴을 활용한 혼합토가 강도, 투수, 지지력 특성이 우수한 것으로 나타나 토공재료고서 사용가능한 것으로 나타났다.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2005년도 총회 및 춘계학술발표회
• /
• pp.237-241
• /
• 2005

The physical and chemical characteristics of soils in a small watershed were investigated and the effect of geology and land use on soil quality were examined by using multivariate statistical methods, principal components analysis and discriminant analysis. It was considered that the accumulation of salts in the farmland soils indicated by electrical conductivity, contents of cations and anions and pH was caused by fertilizer input during cultivation. The contents of inorganic components are increased as following order: upland > orchard > paddy field > forest. The results of two discriminant analyses using water extractable inorganic components and their ratios by land use were also clearly classified by discriminant function 1 and 2. In discriminant analysis by components, discriminant function 1 indicated the effect of fertilizer application and increased as following order: upland > orchard > paddy field > forest soil.

• 전기학회논문지
• /
• 제65권12호
• /
• pp.1971-1978
• /
• 2016

In this paper, electrical and physical characteristics associated with the ionization growth of soil under impulse voltages in a coaxial cylindrical electrode system to simulate a horizontally-buried ground electrode were experimentally investigated. The results were summarized as follows: Transient ground resistances decreased significantly by soil ionization. The voltage-current (V-I) curves for non-ionization in soil lined up in a straight line with the nearly same slope that is the ground resistance, but they showed a 'cross-closed loop' of ${\infty}$-shape under ionization. The conventional ground resistance and equivalent soil resistivity were inversely proportional to the peak value of injected impulse currents. On the other hand, the equivalent ionization radius and time-lag to the maximum value of ionization radius were increased with increasing the incident impulse voltages. An analysis method for the transient ground resistances of the ground electrode based on the ionization phenomena was proposed. The proposed method can be applied to analyze the transient performances of grounding systems for lightning protection in power system installations.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2010년도 추계 학술발표회
• /
• pp.1201-1212
• /
• 2010

In order to investigate on the effect of stabilization methods for rice paddies contaminated by heavy metals, a series of lab-scale model test was carried out by applying the characteristics of submerged Paddy soil. To perform the lab-scale model test, columns were made by acrylic with the dimension of diameter=10cm, thickness=0.5cm and were filled with soils which was contaminated were mixed with stabilization agents(lime stone 5% and steel refining slag 5% respectively). To manipulate the reduction condition, soils in the columns were submerged with distilled water. And then soil water and subsurface water in each column were sampled in the regular term and analysed the various physical and chemical properties.