• Magazine of the Korean Society of Agricultural Engineers
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• v.37 no.2
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• pp.41-52
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• 1995

혼합상태에서 유기화합물들이 토양에 흡착하는 성질에 관해서 5개의 유기화합물(페놀,2,4-디크로로페놀, 2,4,6-트리크로로페놀, 부루신, 따이오유리아)과 2종류의 토양을 이용하여 연구하였다. 일반적으로 따이오유리아를 제외하고는 한가지 물질이 혼합상태에 있는 다른물질이에 의 흡착력이에 제약을 받아서 단독으로 있을때 보다 흡착율이 낮았다. 따이오유리아는 단독인 경우보다 혼합상태일 때 더 많은 흡착을 보였는데 이는 혼합상태에서 오히려 흡착이 증가할수도 있음을 나타낸다. 혼합이 흡착에 비치는 영향은 페놀의 혼합상태와 단독상태에서의 흡착상태를 여러가지 형태로 비교하여 검토하였는데 산성이고 유기물질이 많은 토양보다 혼합으로 인한 흡착의 억제 효과가 뚜렷하였다.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.837-843
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• 2010

This research investigated classification of clay activity degree by different clay mineral components. Based on compositions of different clay and oxide minerals within 390 soil series in Korea, 7 soils were selected to analyze for CEC and specific surface area of clay minerals. As a result, soils were mainly composed with Chlorite originated from sandstone, Smectite originated from Andesite porphyry and combination of Allophane and Ferrihydrite originated from volcanic ash, if the ratio of CEC value to clay content (degree of clay activity) was greater than 0.7. If the degree of clay activity was ranged between 0.3 and 0.7, soils were composed mainly with Kaolin originated from anorthite. Soils with this ratio also was composted with combinations of Kaolin, Illite and Vermiculite originated with river deposits. When the degree of the activity was less than 0.3, soils were commonly red-yellowish color and composed with two different minerals. One type of composition was Kaolin originated from granite and granite gneiss and the soils contained Geothite and Hematite. The other type was composited mainly with Illite and Vermiculite minerals originated from granite. These soils contained Gibbsite, Geothite and Hematite. The degree of clay activity was highly related with CEC and specific surface area. The greater degree of the activity displayed greater values of clay CEC and specific surface area. It is not easy to measure actual quantity and compositions of clay minerals, while the degree of clay activity can be measured from routine soil analyses. As a conclusion, the degree of clay activity may be not just a simple but also powerful tool to estimate physical-chemical properties of soils and to evaluate the soil classification in Korean soils.

• Proceedings of the Korea Water Resources Association Conference
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• 2009.05a
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• pp.1068-1071
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• 2009

현재 한강수계의 화천댐 상류, 임진강 상류지역의 상당부분이 북한에 속해있다. 따라서, 장기유출모의 수행을 위한 기본입력자료인 수문기상자료 및 수치주제도(토지이용, 토양)의 활용에 있어 미계측 유역으로 간주되어 왔다. 그러나, 전세계 기상통신망(GTS: Global Telecommunication System)을 통해 수문기상자료(강수량, 기온, 습도, 풍속 등)는 기상청에서 제공되고 있으며, 국제연합대학(United Nations University)에서 추진하고 있는 WaterBase 프로젝트를 통해 토지이용도(24종류, 1km 해상도) 및 토양도(5,000종류, 10km 해상도)를 활용할 수 있는 상황이다. 하지만, 언급한 자료에 대한 국내검토는 충분히 이루어지지 못하고 있다. 따라서, 본 연구에서는 화천댐 상류유역을 대상으로 전세계 기상통신망 수문기상자료와 전지구 토지이용과 토양자료에 대한 검토를 수행하였다. 또한 물리적 기반의 장기유출모형인 SWAT-K의 입력자료로 활용하여 유역물수지 및 유출분석을 실시한 후, 그 적용성을 평가하였다. 이러한 연구는 기후변화 및 북한지역의 댐건설과 같은 한강수계의 수문학적 조건 변화로 인한 수자원 관리 및 계획를 위해 보다 활발히 이루어져야 할 것으로 판단된다.

• Journal of Korea Water Resources Association
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• v.34 no.6
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• pp.735-743
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• 2001

CN procedure has been proven to be useful method for evaluating the effects of changes in land-use and treatment on hydrology. In this study, the use of Landsat multi-spectral image was investigated for analyzing the land-use distribution. From the Landsat data, forest areas were classified according to the density of trees. Watershed CN's were calculated to analyze the effects of the density of trees and soil cover types on direct runoff. According to the results, the density of trees had a little effect while soil cover types had a large effect on CN, From the comparison of estimated runoffs from CN method with observed runoffs, detailed soil cover map provides improved results.

• Journal of Soil and Groundwater Environment
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• v.13 no.5
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• pp.47-56
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• 2008

Temporal changes of metal solubility have been repeatedly observed in soils equilibrated with metal salt solutions. This phenomenon is known as aging, yet factors that affect the degree of metal aging remain largely unexamined. In this study, we compared the extent of aging on metal partitioning depending on soil, metal, and metal loading. Five soils spiked with four levels of Cd (2.5-20 mg ${kg}^{-1}$), Cu, and Zn (50-400 mg ${kg}^{-1}$) salt solutions were aged in the laboratory up to 1 year. The partitioning coefficient ($K_d$) of each metal was calculated from the ratio of total to dissolved metal concentration in samples collected at times ranging from 1 day to 1 year. The highest $K_d$ values for Cd, Cu and Zn were recorded in a Histosol, Andisol, and fine-textured Alfisol, respectively, whereas the lowest $K_d$ was recorded for an Oxisol and coarsetextured Alfisol. For all soils, a pattern of increasing Kd with aging was evident for Cd and Zn, but not Cu. Rapid Cu sorption was limited when dissolved organic matter was high in soils. In highly-retentive soils, $K_d$ values seemed to be insensitive to metal loading, although a longer period was required for the higher metal loadings to reach the same degree of metal aging as the lower loadings. In soils with low sorption capacity, the $K_d$ values were determined more by metal loading than by aging. Therefore, marked differences can be expected in the degree of metal aging in spiked soils by the soil type, metal and amount of metal added.

• Journal of Korea Soil Environment Society
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• v.3 no.3
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• pp.3-10
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• 1998

Acid/Base buffer capacity of soil is very important in prediction of contaminant transport for its direct impact on pH change of the system composed of soil-contaminant-water, In this research, diffuse double layer theory as well as two layer electrostatic adsorption model are applied to develop a theoretical model of buffer capacity of soil. Model application procedures are presented as well. Buffer capacity of Georgia kaolinite and Milwhite kaolinite was measured by acid-base titration. Model prediction and experimental results are compared.

• Weed & Turfgrass Science
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• v.7 no.2
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• pp.148-157
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• 2018

Research was initiated to evaluate four domestic and overseas organic soil amendments (SAs) on turfgrass groundcover and density and to provide basic information on practical sports turf establishment. This study was conducted in Agrostis palustris Huds. (CB) grown in sand-based root zone. A total of 20 treatments of SA+sand were prepared by mixing 10 to 50% (v/v). These amendments were SABP (Berger Peat), SAEP (Eco-Peat), SAGS (G1-Soil), and SAPP (Premier Peat). Turfgrass groundcover and density significantly varied with SAs, its mixing rate to sand and week after seeding (WAS). Cumulative turfgrass density was variable, but a great change occurred between 2 and 4 WAS. Turfgrass density at 2 WAS ranged from 36.7 (SABP 30) to 89.7% (SAGS 20), being 53.0% in differences among treatments. However, CB reached to carrying capacity around 6 WAS. Thus, most treatments were similar to 90% or so in density. At the end of study, overall groundcover ranged between 60.7 (SAEP 10) and 96.7% (SAPP 50). Proper mixing rate was variable with SAs, being 10 and 20% for SABP and SAGS, respectively. But the optimum rate was 50% for both SAEP and SAPP.

• Asian Journal of Turfgrass Science
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• v.16 no.1
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• pp.11-18
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• 2002

This research was designed to know optimize soil sampling time, soil sampling depth and fertilizers according to season and soil condition in the golf course. One of the results was revealed that sampling point and depth have to be consistent for much fluctuation by sampling. Especially, Soil pH is decreased by soil depth remarkably. Top soil (0-5 cm depth) pH is higher than the sub soils (5-10 cm, 10-15 cm depth). It was confirmed that soil pH would increase when the state of soil is appropriate to H$^{+}$ ion concentration. Therefore, Soil pH modification is always not determined by lime content rather than soil conditions, i.e., Organic matter content, moisture content, and soil air content. More effective fertilizing time according to soil pH correction is the middle of october, and it's quantity is 100 g/$m^2$ silicate and 200 g/$m^2$ lime (Pel-Lime Mini) in this experiment. Recommended soil sampling method for acidity measurement is dividing by soil depth into each 5 cm respectively, rather than mixing 15 cm total soil.

• Journal of the Korea Organic Resources Recycling Association
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• v.7 no.2
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• pp.35-45
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• 1999

The effect of compost to force the cultivation using various soil and vegetation was investigated 5 times in the field for 4 years. Sewage sludge compost was validated to be useful fertilizer for the growth of a plant. and the optimal amendment amounts of compost to soil depended on the kinds of soil and vegetation, and the organic contents of compost. In the case of compost with high organic content. the optimal amended compost weight was 0.12t/are in fertile-dark brown(eutrophic) soil, 0.2t/are in sandy soil(trophic) and 0.4t/are in infertile-dark brown(oligotrophic) soil, respectively. In the case of compost with low organic content. on the other hand, the amentments of compost up to 0.6t/are was allowable without negative effect on the applied vegetation. Consequently, it can be believed that the sewage sludge compost is useful fertilizer, if keep the optimal amendment amounts(0.4t/are. year) to improve soil on cultivation of vegetation.

• The Korean Journal of Pesticide Science
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• v.2 no.1
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• pp.70-78
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• 1998

This study was conducted to investigate the adsorption-desorption characteristics of herbicide paraquat on clay minerals, humic materials, and soils under the laboratory conditions. Adsorption time of paraquat on clay minerals was faster than organic materials and soils. Adsorption amount on montmorillonite, 2:1 expanding-lattice clay mineral, was largest among the adsorbents tested. The adsorption capacity of paraquat was approximately 21 % of cation exchange capacity in soils, 45.1 % in kaolinite, and 80.6% in montmorillonite. Humic materials, humic acid and fulvic acid isolated from soil II, adsorbed larger amount of paraquat than kaolinite and soils. Distribution of tightly bound type of paraquat was larger in clay mineral and soils but loosely bound type was larger in humic acid and fulvic acid. In oxidized soil, the adsorption amount of paraquat was decreased to 85.1-95.5% of original soils. Distribution of unbound and loosely bound type of paraquat was decreased in oxidized soil but tightly bound type was increased. The competition cations decreased paraquat adsorption on humic materials and soils but not affected on montmorillonite. No difference was observed as the kinds of cations. In cation-saturated adsorbents, the adsorption amount was decreased largely in humic materials and soils but decreased a little in montmorillonite. The tightly bound type of paraquat in all adsorbents was not desorbed by pH variation, sonication, and cation application but loosely bound type was desorbed. However, the desorption amount was different as a kinds of adsorbents and desorption methods.