• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 1996년도 경북지부 결성 및 추계학술발표회 논문집
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• pp.58-62
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• 1996

To check the variability of the effective diffusion coefficient in the unsaturated porous soil media. a Monte Carlo simulation was done for the equation suggested by Millington and Quirk(1961). The results shows that the probability density function of D$_{c}$/D$_{o}$ is positively skewed. It means the chance of having less effective diffusion coefficient values in the soil media than mean value is high. Also, the distribution types of D$_{c}$/D$_{o}$ are about same regardless of assumed distribution types of input parameters.ers.ers.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권1호
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• pp.17-23
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• 2019

Clean soil environment is of crucial importance to sustain lives of ecosystem and humans. With rapid industrialization, there has been a great increase of soil contamination by accidental releases of petroleum products. In general, soil remediation is an expensive and time-consuming process as compared to cleanup of water and air. Moreover, determining the source and responsible parties of soil pollution often turns into legal conflicts and that further delay the cleanup process of contaminated sites. In practice, total petroleum hydrocarbon (TPH) analysis has been employed to determine the petroleum species and to track down the responsible polluters. However, this approach often suffers from differentiating similar TPH species. In this study, we analyzed TPH chromatogram patterns of 24 domestic petroleum products in specific carbon ranges (${\sim}C_{10}$, $C_{10}-C_{12}$, $C_{12}-C_{36}$, and $C_{36}{\sim}$) and the fractional changes of THP ratio in the mixture products of gasoline, kerosene and diesel. The proposed TPH analysis method in this study could serve as a useful tool to better analyze the petroleum species in soils contaminated with complex oil mixtures, and ultimately be used to identify the polluters of soil.

• 한국지하수토양환경학회지:지하수토양환경
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• 제26권1호
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• pp.1-7
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• 2021

Air-water interfacial area is of great importance for the analysis of contaminant mass transfer processes occurring in the soil systems. Capillary bundle model has been proposed to estimate the specific air-water interfacial areas in unsaturated soils. In this study, the measured air-water interfacial areas of a soil (loam) using the gaseous interfacial tracer technique were compared to those from capillary bundle model. The measured values converged to the specific solid surface area (7.6×104 ㎠/㎤) of the soil. However, the simulated air-water interfacial areas based on the capillary bundle model deviated significantly from those measured. The simulated values were substantially over-estimated at low end of the water content range, whereas the model under-estimated the air-water interfacial area for the most of the water content range. This under-estimation is considered to be caused by the nature of the capillary bundle model that replaces the soil pores with a bundle of glass capillaries and thus no surface roughness at the inner surface of the capillaries is taken into account for the estimation of the air-water interfacial area with the capillary bundle model. Subsequently, appropriate correction is necessary for the capillary bundle model to estimate the air-water interfacial area in soils. Since the soil-moisture release curve data is the basis of the capillary bundle model, the model can be of use due to its simplicity, while the gaseous tracer technique requires complicated experimental equipment followed by moment analysis of the breakthrough curves. The size distribution profile of the pores filled with gas estimated by the water retention curve was found to be similar to that of particle size at different size range. The shifted distribution of gas-filled pores toward smaller size side compared to the particle size distribution was also found.

• 한국수자원학회논문집
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• 제37권1호
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• pp.31-41
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• 2004

국내산지사면의 토양수분 시공간적 분포상황을 파악하기 위한 토양수분 측정법이 개발되었다. 대상유역을 정밀측정하여 수치고도모형을 구성한 다음 흐름분배 알고리즘을 적용하고 공간적 변화의 대표성을 최대화하기 위한 측정체계를 구축하였다. 토양수분이 강우-유출형성과정에 기여하는 기작을 표현하는 유도과정도 전개되었다. 측정은 설마천 유역의 법륜사 우측사면에서 수행되었다. 다중 측정망의 운영을 통하여 시공간적으로 변화하는 토양수분 자료를 획득하였다. 습한 조건에서 토양수분이 토양수분 추정 알고리즘과 비교적 높은 상관도를 보여주었다.

• 한국농공학회:학술대회논문집
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• 한국농공학회 2003년도 학술발표논문집
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• pp.191-194
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• 2003

The purpose of this paper was to derive soil-water characteristic curve equation for unsaturated soil. To this end, a series of suction measured test was conducted on the selected 4 kinds of soil which is located in Korea, used the modified pressure plate apparatus. From the test results, it was proved that characteristic curve changes according to grain size distribution, size of void and fine grained soil contents. Residual degree of saturation(Sr) was decreased with void ratio and changed with fine grained soil contents, parameter ${\lambda}$ and hr was increased with void ratio. Soil-water characteristic curve equation based on the test result was suggested by void ratio or grain size distribution.

• 한국환경복원기술학회지
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• 제9권1호
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• pp.72-88
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• 2006

The optimal environmental ranges of the establishment phase for the distribution of Zizania latifolia and Typha angustifolia was determined to develop a set of basic data and criteria of planting substrate for the restoration, conservation and management of wetlands. The study was carried at 17 wetlands in the Kyunggi-do and Gyeongsangnam-do region where inland wetlands place intensively in June, 2005. Total 127 quadrats were sets in growing areas of Zizania latifolia and Typha angustifolia. $NO_3-N$, K, Ca, Mg and Na in the water variables and soil texture, LOI (loss on ignition), soil pH and soil conductivity in the soil variables were analyzed. The optimal range of water depth for the distribution of Zizania latifolia was -5~39cm, $NO_3-N$ content of water was <0.01~0.19ppm, K content of water was 0.1~5.9ppm, Ca content of water 0.5~44.9ppm, Mg content of water was 1.2~11.9ppm, Na content of water 3.4~29.9ppm, water conductivity was 48~450${\mu}S$/cm, respectively. The optimal range of LOI for the distribution of Zizania latifolia was 1.7~11.9%, soil conductivity was 25.5~149.9${\mu}S$/cm, respectively. The optimal range of water depth for the distribution of Typha angustifolia was -20~24cm, $NO_3-N$ content of water was <0.01~0.19ppm, K content of water was 0.2~2.9ppm, Ca content of water 0.6~19.9ppm, Mg content of water was 0.2~5.9ppm, Na content of water 3.5~19.9ppm, water conductivity was 96~450${\mu}S$/cm, respectively. The optimal range of LOI for the distribution of Typha angustifolia was 2.4~15.9%, soil conductivity was 17.6~149.9${\mu}S$/cm, respectively. The optimal soil texture were loam, silt loam and sandy loam in both species. The lower water depth (-20~40cm) is appropriate to increase biodiversity in both species dominated community and it is better to maintain water depth of 40~100cm for water purification. Both species appear frequently in the soil with high silt content.

• 한국지리정보학회지
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• 제7권2호
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• pp.47-56
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• 2004

본 연구는 강우-유출 침식성 인자의 빈도별에 따른 토양유실량을 평가하고 이롤 바탕으로 유역의 토침칭식 위험지역을 분석하는 것을 목적으로 한다. RUSLE는 토양침식량을 분석하는데 이용하였다. 연구지역은 섬진강 수계의 관촌유역을 선정하였다. 빈도별 강우-유출 침식성인자를 얻기 위하여 39년간의 일일최대 강우량 자료를 이용하였다. 확률강우량은 Normal 분포, Log-Normal 분포, Pearson type III 분포, log-Pearson type III 분포 및 Extreme-I 분포를 이용하였다. 이 중 적합도가 가장 높은 것으로 판단되는 Log-Pearson type III 분포를 채택하였다. Log-Pearson type III 분포는 24시간 확률 강우량을 산정하는데 이용하였고, 빈도별 강우-유출 침식성 인자는 Huff 분포비로 평가하였다. 분석결과 2년빈도에서 200년 빈도까지 토양유실량은 평균 $12.8{\sim}68.0ton/ha{\cdot}yr$로 분석되었다. 유역의 토양유실량 분포를 4개 분류등급으로 구분하여 토양침식 위험지역을 분석하였으며, 침식발생 위험지역으로 판단되는 지역은 분류등급 IV로 하였다. 분류등급 IV의 면적은 $0.01{\sim}5.28km^2$로 전체 농경지 면적의 0.02~9.00%로 나타났다. 특히, 200년빈도의 경우 분류등급 IV에서 밭작물 재배지역이 전체 농경지 면적의 77.1%를 차지하는 것으로 나타났다. 농경지의 경작상태에 따라 토양유실이 큰 영향을 받는 것으로 판단된다.

• 한국환경과학회지
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• 제3권4호
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• pp.409-416
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• 1994

This study was Performed to evaluate the contents of heavy metals in water, sediment and soil of the 7 different sampling points along the West Nakdong river, The results were as follows: the concentrations of Zn, p, Pb, Cd, Mn, Cu and As in the sediment were 197.48, 551.85, 67.01, 2.54, 491.39, 42.95 and 10.52ppm, respectively. The concentrations of Zn, p, Pb, Cd, Mn, Cu and As in the soil was 83.32, 482.89, 17.15, 1.02, 226.02, 26.15 and 7.29ppm, respectively. The concentration ratios of heavy metals In the water to the sediment were 593 - 12700 (Cd >> Cu > Zn > Mn > As > Pb) and that of the water to the soil were 152 - 5100 (Cu > Cd > Zn > Mn > As >Pb). The correlation coefficients of Cu and Pb weve high among the water, sediment and soil. Because the accumulation amounts of heavy metal in the sediment were high, the concentration of heavy metals in the sediment was higher than in soil. The correlation coefficient of heavy metals among water, sediment and soil was high (0.79 - 0.95). Key Words Distribution Characteristics, heavy metals, West Nakdong River.

• 한국수자원학회논문집
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• 제34권4호
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• pp.391-401
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• 2001

토양수분의 공간적 분포를 예측하기 위하여 지표면 곡률관련인자, 지형흐름인자, 태양에너지 복사인자들을 계산하였다. GPS와 토양수분측정기를 활용한 산지유역에서의 토양수분측정은 토양수분의 공간적 분포자료의 구축을 가능하게 했다. 측정된 토양수분자료와 토양수분 추정인자 사이의 상관관계를 분석하였다. 다중회귀분석을 통한 토양수분 추정인자와 토양수분의 공간적 분포상황에 대한 검토는 수치고도모형(DEM)의 분석을 통한 토양수분 추정능력의 가능성과 한계성을 보여주었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제15권3호
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• pp.7-14
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• 2010

Ecological Risk Assessment (ERA) supports a decision-making process such as establishment of environmental quality criteria. Soil quality criteria (SQC) are essential to protect soil organisms from the exposure to various soil contaminants. In this study, ERA methodologies of advanced countries for soil pollution were extensively compared to propose the ERA approach suitable for soil ecosystem in Korea. The soil ERAs in European Chemical Bureau(ECB), The Netherlands, and Canada can be classified as deterministic ecological risk assessment (DERA), and probabilistic ecological risk assessment (PERA) based on species sensitivity distribution (SSD). We propose three ERA methods according to abundance and reliability of soil ecotoxicity data. The method considered land use such as residential/agricultural, and industrial/commercial uses. The taxonomic groups of soil organism were classified as 'Class' level including different trophic levels (Magnoliopsida or Liliopsida, Clitellata, and Insecta or Secernentea). This study can be used to estimate the soil quality criteria to protect soil biota.