Analysis of Catena on Representative Soils derived from Granite and Granite Gneiss

손연규,조현준,현병근,전현정,신국신 한국토양비료학회 2015 한국토양비료학회지 Vol.48 No.4

Soil catena can be characterized by some properties, such as drainage levels and soil textures. Characteristics of soil catena are different drainage levels from a summit to the direction of gravity and similar soil textures. Therefore this study was performed GIS (Geographic information system) and statistical analyses using perimeters from soil series in order to characterize quantitatively and objectively soil distributional properties in Korea. The total of 16 soil series from representative granite and granite gneiss originated soils were selected among inland soils from detailed soil maps (1:25,000 scale) in Rural Development Administration (RDA) and analyzed. After the detailed soil maps were merged by soil series unit, perimeters were measured from one soil series to neighboring soil series using functions of table join, merge, dissolve, buffer, and clip in ArcGIS (10.1). The covering ratio of each soil series unit was calculated from neighboring perimeters by soil series and applied to clustering analysis. Soils that were analyzed were the total of 16 soil series; 7 of sandy loam and 9 of clay loam. As a result, analyzed soil series adjoined complicatedly such as Hyocheon series adjoined 26 series and Jisan did 276 series. The results of the clustering analysis showed that soils were clustered by soil textures except a few soil series. This study applied only one property that was a length of neighboring soil series to GIS and statistical analyses. These results were compared to existing soil groups that were classified by new-soil taxonomy, texture, soil type and drainage level. It showed that these analyses can provide soil characteristics by soil texture. Based on this study, there is a need to investigate further objectively and quantitatively in statistical analyses of soil series.

Classification of Anthropogenic Soil “Ingwan” Series

손연규,조현준,현병근,신국신 한국토양비료학회 2015 한국토양비료학회지 Vol.48 No.5

Korean soil classification system is based on the US soil taxonomy. This study aimed to understand and inform the soil taxonomy of 2010 and 2014 US soil classification systems. Ingwan series belonged to anthropogenic soil was classified to coarse loamy over sandy, mixed, mesic family of Aquic Udorthents based on the soil taxonomy of 2010 and coarse loamy over sandy, mixed, mesic family of Anthroportic Udorthents based on the soil taxonomy of 2014. An anthropogenic soil is increasing in Korea. Considering the domestic relationship depending on US soil taxonomy, it is important to be well-informed of the taxonomy and apply the updated taxonomy system properly to the domestic soil classification. This study of defining the anthropogenic soil will provide useful information on soil management and its utilization.

A Study on Soil Characteristics of Paddy Fields with Re-established Soils

손연규,문용희,장용선,정강호,조혜래,현병근,신국신,한경화 한국토양비료학회 2015 한국토양비료학회지 Vol.48 No.3

Six study sites in Gumi, Goryeong in Gyeongbuk province and Naju in Jeonnam province were selected to investigate soil properties of poorly drained horizons in paddy soils. The horizons were re-established layers which were parent material layers originated from fluvial deposits. Topsoil layers were differentiated from piled parent materials while soil structure of the topsoil layer was massive with striated microstructure. Compaction at soil re-establishment and a lack of structure and aggregate development in these soils may cause the limitation of vertical water movement and result in poorly drained horizons. Soil samples were taken from paddy fields with top soils of sandy loam, silt loam and silty clay loam and re-established soils of coarse and fine texture. The samples were taken from each horizon for the analyses of soil chemical and mineral properties. Soils with re-established soils of coarse texture had greater amounts of sands from top soil texture distributions, while soils with fine texture had greater amounts of silts. Chemical properties of top soils were analyzed from rice cultivated soils at the time of re-establishments and one year after the re-establishments. The coarse texture of the re-established horizons decreased in EC values from 0.23 to 0.11 (dS m -1 ), available phosphate values from 112 to 54 (mg kg -1 ), and exchangeable Ca values from 6.6 to 4.9 (cmolc kg -1 ). On the other hand, soils with fine texture showed decrease only in pH and exchangeable Ca values. Especially, organic matter and available phosphate contents showed heterogeneous distributions from each horizon. This result may be caused by mixture of plough layer and subsurface layer during and consolidation. Hydraulic conductivity values were low at the boundaries of top soil and parent material layers except SL/coarse soil. Soil microstructure was massive structure without soil clods or pores and showed striated structure. Therefore, re-established paddy fields with fluvial deposits as parent material layers showed limited vertical movements of soil water because of occurrence of compacted layers and less-development of soil clods and aggregates.

Comparison of Soil Pore Properties between Anthropogenic and Natural Paddy Field Soils From Computed Tomographic Images

전현정,정기열,최영대,조수민,이상헌,현병근,신국신,손연균,강항원 한국토양비료학회 2015 한국토양비료학회지 Vol.48 No.5

Human influence on soil formation has dramatically increased with human civilization and industry development. Increase of anthropogenic soils induced researches on the anthropogenic soils; classification, chemical and physical characteristics of anthropogenic soils and plant growth from anthropogenic soils. However there have been no comprehensive analyses on soil pore or physical properties of anthropogenic soils from 3 dimensional images in Korea. The objectives of this study were to characterize physical properties of anthropogenic paddy field soils by depth and to find differences between natural and anthropogenic paddy field soils. Soil samples were taken from two anthropogenic and natural paddy field soils; anthropogenic (A_c) and natural (N_c) paddy soils with topsoil of coarse texture and anthropogenic (A_f) and natural (N_f) paddy soils with topsoil of fine texture. The anthropogenic paddy fields were reestablished during the Arable Land Remodeling Project from 2011 to 2012 and continued rice farming after the project. Natural paddy fields had no artificial changes or disturbance in soil layers up to 1m depth. Samples were taken at three different depths and analyzed for routine physical properties (texture, bulk density, etc.) and pore properties with computer tomography (CT) scans. The CT scan provided 3 dimensional images at resolution of 0.01 mm to calculate pore radius size, length, and tortuosity of soil pores. Fractal and configuration entropy analyses were applied to quantify pore structure and analyze spatial distribution of pores within soil images. The results of measured physical properties showed no clear trend or significant differences across depths or sites from all samples, except the properties from topsoils. The results of pore morphology and spatial distribution analyses provided detailed information of pores affected by human influences. Pore length and size showed significant decrease in anthropogenic soils. Especially, pores of A_c had great decrease in length compared to N_c. Fractal and entropy analyses showed clear changes of pore distributions across sites. The topsoil layer of A_c showed more degradation of pore structure than that of N_c, while pores of A_f topsoil did not show significant degradation compared with those of N_f. These results concluded that anthropogenic soils with coarse texture may have more effects on pore properties than ones with fine texture. The reestablished paddy fields may need more fundamental remediation to improve physical conditions.

Hot Wall Epitaxy 방법으로 Hg0.8 Cd0.2 Te / CdTe ( 111 ) , CdTe ( 110 ) 의 제작과 특성에 관한 연구

신영진,정태수,신현길,김택성,이훈,강신국,신영신,정경수,유병열,홍광준 대한전자공학회 1994 대한전자공학회 학술대회 Vol.1994 No.1

승화법에 의한 CdS 단결정 성장

정태수,김현숙,유평렬,신영진,신현길,김택성,정철훈,이훈,신영신,강신국,정경수,홍광준,Jeong, T. S.,Kim, H. S.,Yu, P. Y.,Shin, Y. J.,Shin, H. K.,Kim, T. S.,Jeong, C. H.,Lee, H.,SHin, Y. S.,Kang, S. K.,Jeong, K. S.,Hong, K. J. 한국결정성장학회 1993 韓國結晶成長學會誌 Vol.3 No.2

수직 2단 전기로를 제작하고 결정성장관에 꼬리관을 연결하여 seed 결정없이 승화 방법으로 CdS 결정을 성장하였다. 이때 시료부분과 성장부분의 온도차 ${\Delta}T$가 이론적인 값 $14.7^{\circ}C$와 비교해서 실험적으로 얻은 값이 $15^{\circ}C$ 로 아주 일치하는 값을 나타내었다. 이때 꼬리관의 온도를 $110^{\circ}C$로 시간당 0.38mm 정도로 빨리 결정성장관을 끌어 올려 결정을 성장하였다. 분말법의 X-선 회절무늬와 Laue 배면 반사법의 Laue 무늬로부터 성장된 결정이 육방정이고 결정성장관의 길이 방향으로 c축을 갖는 단결정임을 확인하였다. 또한 CdS 단결정은 상온에서 전자 이동도와 운반자 밀도는 각각 $316cm^2/V{\cdot}sec$와 $2.90{\times}10^{16}cm^{-3}$정도이였다. We has made 2-zone vertical electric furnace and has been grown CdS single crystal by sublimation method in crystal growth tube with tail tube without seed crystal for growth. While it has been growing, temperature difference ${\Delta}T$ of source and growth part has nearly agreed with theoritical value $14.7^{\circ}C$and experimental value $15^{\circ}C$ Then, crystal of best quality has been grown, when temperature of tail tube has been $110^{\circ}C$, in spite of quickly pulling up crystal growth tube a degree O.38mm per hour. The grown crystal have had hexagonal structure and single crystal with c-axis to length of crystal growth tube from X- ray diffraction pattern of powder method and Laue pattern of back reflection Laue method. Also, the mobility and carrier density from Hall effect measurement have been $316cm^2/V{\cdot}sec$ and $2.90{\times}10^{16}cm^{-3}$ at the room temperature, respectively.

승화법에 의한 CdS 단결성 성장

정태수,김현숙,유평렬,신영진,신현길,김택성,정철훈,이훈,신영신,강신국,정경수,홍광준 全北大學校 基礎科學硏究所 1994 基礎科學 Vol.16 No.-

수직 2단 전기로를 제작하고 결정성장관에 꼬리관을 연결하여 seed 결정 없이 승화 방법으로 CdS 결정을 성장하였다. 이때 시료부분과 성장부분의 온도차 ΔT가 이론적인 값 14.7℃와 비교해서 실험적으로 얻은 값이 15℃로 아주 일치하는 값을 나타내었다. 이때 꼬리관의 온도를 110℃로 시간당 0.38mm 정도로 빨리 결정성장관을 끌어 올려 결정을 성장하였다. 분말법의 X-선 회절무늬와 Laue 배면 반사법의 Laue 무늬로 부터 성장된 결정이 육방정이고 결정성장관의 길이 방향으로 c축을 갖는 단결정임을 확인하였다. 또한 CdS 단결정은 상온에서 전자 이동도와 운반자 밀도는 각각 316㎠/V·sec와 2.90× 10 exp (16)cm^-3 정도이였다. We has made 2-zone vertical electric furnace and has been grown CdS single crystal by sublimation method in crystal growth tube with tail tube without seed crystal for growth. While it has been growing, temperature difference ΔT of source and growth part has nearly agreed with theoritical value 14.7℃ and experimental value 15℃. Then, crystal of best quality has been grown, when temperature of tail tube has been 110℃, in spite of quickly pulling up crystal growth tube a degree 0.38mm per hour. The grown crystal have had hexagonal structure and single crystal with c-axis to length of crystal growth tube from X-ray diffraction pattern of powder method and Laue pattern of back reflection Laue method. Also, the mobility and carrier density from Hall effect measurement have been 316㎠/V·sec and 2.90× 10 exp (16)cm^-3 at the room temperature, respectively.