• Applied Biological Chemistry
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• 제44권2호
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• pp.92-96
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• 2001

농경지로의 개발 가능성이 높은 중국 길림성 백성지역의 주요한 토양인 흑개토의 이화학성 및 인산 흡착특성을 조사하였다. 토지 이용방식 또는 재배작물이 서로 다른 중국 길림성 백성지역 4곳과 중국 용정에 위치한 연변 대학교 농과대학 부속 시험장 1곳에서 1993년 8월에 토양을 채취하여 실험을 수행하였다, 중국 길림성 백성지역 토양의 $_PH$는 미경작지 10.2, 경작지는 $7.3{\sim}7.6$으로 비교적 높았다. 양이온 치환용량은 20 cmol(+) $kg^{-1}$ 이상이었으며, 치환성 양이온 중 Na는 특히 표토에 많이 존재하였으며, Ca의 함량이 매우 높아 Ca 포화율이 100% 이상을 나타내었다. 토양 포화 침출액의 주요 양이온은 Na이었으며, ECe와 SAR을 기준으로 백성 미경작지 토양은 염류-나트륨성 토양, 경작지 토양은 나트륨성 또는 일반 토양에 해당하였다. 백성지역 토양의 유효인산 함량은 10mg P $kg^{-1}$ 미만으로 아주 낮았으며, 최대 인산흡착량은 $ $ mg P $kg^{-1}$이었다. 길림성 백성지역 토양의 경우 유효인산 함량이 매우 낮아 토양 비옥도 중진을 위한 인산질 비료의 시용과 함께 토양 투수성의 개선 등과 같은 적절한 토양 관리가 필요하며, 용정지역 토양의 경우에는 인산흡착 특성을 고려하여 인의 과잉 축적을 방지하기 위한 인산질 비료의 적정 시용을 권장하여야 한다.

• 한국토양비료학회지
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• 제45권5호
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• pp.733-737
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• 2012

The objectives of this study were to investigate soil chemical properties for forest rehabilitation and suggest design and management in abandoned coal mine areas in Mungyeong, Gyeongsangbuk-do. Total study sites were 10 sites, and soil analysis particular were soil pH, TOC, total-N, C/N ratio, A.v. $P_2O_5$, and CEC. Because most of study sites showed soil pH from 5.0 to 7.0, it seems that soil pH does not affect growth of vegetation. But soil pH in Danbong1 was acidic (pH 4.6), so it is needed to improve with ameliorant such as limestone. Most of study sites is necessary to manage for organic matter and Nitrogen, because there sites showed lower value of TOC and total-N than general forest. The values of A.v. $P_2O_5$ and CEC were good in most of study sites, so it seems that they do not have effect on vegetation growth. All of soil factors has no regression according to elapsed time after rehabilitation. TOC, total-N and A.v. $P_2O_5$ among soil properties have positive relationship between each other. It is necessary to fertilizer for organic matter and Nitroge because of value in TOC, total-N and C/N ratio. The results of this study were analyzed only one time. So, long-term monitoring for soil properties is important for the correct forest rehabilitation and management.

• 한국습지학회지
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• 제12권2호
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• pp.1-12
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• 2010

본 연구에서는 비교적 도심 가까이에 위치하는 부산광역시 금정산 산지습지의 지질학적 특성을 규명하였다. 야외조사와 실내분석에 의해서 금정산 산지습지의 지형, 지질, 구조지질학적 특성, 습지로부터의 거리에 따른 암석의 강도, 습지의 토양단면, 토양의 화학적 특성을 파악하였다. 금정산 습지의 기반암은 각섬석화강암이며, 습지 주변의 각섬석화강암과 유문암질암의 절리의 주향은 대체로 남북방향, 동서방향, 북동-남서방향이며 $60^{\circ}$ 이상의 급한 절리 경사각을 가지고 있다. 또한 습지에 가까울수록 암석의 강도가 낮아지고 풍화도는 높아짐을 알 수 있다. X선 회절분석에 의하면, 습지 토양시료에는 카올리나이트, 몬모릴로나이트, 깁사이트가 나타나며, 이는 장석의 풍화산물임을 지시한다. 습지 토양의 단면은 지표에서부터 O, A, B, C층의 순서로 놓여 있으며, 유기물 함량은 토양의 심도가 깊어질수록 감소하는 경향성을 보이고 있다. 또한 습지 토양의 무기물 성분 중 $K^+$와 $Na^+$의 농도가 높게 나타나며, 이는 장석의 풍화에서 유래함을 지시한다.

• 한국환경과학회지
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• 제30권12호
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• pp.1015-1025
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• 2021

Our research work aimed to evaluate cover crop effects of winter rye on soil characteristics, soil conservation, and yield productivities on potato fields with 15% slope during a fallowed period. There were two controls of bared field without any cultivation and conventional potato cultivation without winter rye. Potato cultivation increased soil pH, organic matter, available phosphate, and exchangeable cation regardless of cover crop cultivation. Sub-soil, particularly, all components of soil chemical properties showed higher value in winter rye cultivation than conventional cultivation. Higher soil density was observed on cover crop cultivation than conventional cultivation resulting from root residues of the cover crop both topsoil and subsoil. Cover crop residues positively affected plant growth and reduced the amount of soil erosion by holding the soil. Although severe soil erosion was seen in conventional cultivation, winter rye cultivation declined soil erosion by 47% during the fallow period on potato slope fields. Distinct soil bacterial communities were detected among treatments and some OTU(Operational Taxonomic Unit)s showed significantly higher abundance in winter rye treatment. Total yield and commercial rate demonstrated no significant differences while higher tuber phosphate, K⁺, and Mg²⁺ contents were observed in winter rye cultivation.

• 한국환경농학회지
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• 제38권4호
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• pp.219-224
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• 2019

BACKGROUND: Soil bacteria play important roles in organic matter decomposition and nutrient cycling during the non-growing season. The purpose of this study was to investigate the effects of soil management and chemical properties on the utilization of carbon sources by soil bacteria in paddy fields. METHODS AND RESULTS: The Biolog EcoPlate was used for analyzing community-level carbon substrate utilization profiles of soil bacteria. Soils were collected from the following three types of areas: plain, interface and mountain areas, which were tested to investigate the topology effect. The results of canonical correspondence analysis and Kendall rank correlation analysis showed that soil C/N ratio and NH₄⁺ influenced utilization of carbon sources by bacteria. The utilization of carbohydrates and complex carbon sources were positively correlated with NH₄⁺ concentration. Cultivated paddy fields were compared with adjacent abandoned fields to investigate the impact of cultivation cessation. The level of utilization of putrescine was lower in abandoned fields than in cultivated fields. Monoculture fields were compared with double cropping fields cultivated with barley to investigate the impact of winter crop cultivation. Cropping system altered bacterial use of carbon sources, as reflected by the enhanced utilization of 2-hydroxy benzoic acid under monoculture conditions. CONCLUSION: These results show that soil use intensity and topological characteristics have a minimal impact on soil bacterial functioning in relation to carbon substrate utilization. Moreover, soil chemical properties were found to be important factors determining the physiological profile of the soil bacterial community in paddy fields.

• 한국토양비료학회지
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• 제46권6호
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• pp.536-541
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• 2013

In Soil Taxonomy system, anthropogenic soils are still classified as Entisols since the International Classification Committee for Anthropogenic Soils is in the process of classifying anthropogenic soils as new orders. In reality, it is difficult to characterize anthropogenic soils because Soil Taxonomy (ST) system does not distinguish between natural and anthropogenic Entisols. On the other hand, World Reference Base for soil resources (WRB) considers human impacts on soils and contains an independent category of anthropogenic soils, which makes easier to understand anthropogenic soil characteristics than Soil Taxonomy system. A remodeled paddy field (Gasan) was selected to classify by ST and WRB. Soil samples were taken to analyze chemical and physical properties. Based on the results of the analyses, the ST system classified Gasan as coarse loamy, mixed, mesic, Aquic Udorthents while the WRB did as Stagnic Urbic Technosols (Oxyaquic, Arenic). As a conclusion, the WRB classification information of the anthropogenic provides more detail characteristics of the anthropogenic soils.

• 한국토양비료학회지
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• 제26권4호
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• pp.278-283
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• 1993

김해통의 Jarosite광물을 화학분석을 통하여 토양 생성학적으로 그 특성을 구명하였다. Jarosite광물이 많이 존재하는 $Bg_2$와 $Bg_3$ 층의 습토와 건토의 pH는 $Bg_3$와 Jarosite 광물 공히 4.0 이하이였으며, 건토의 항온처리에서도 pH는 크게 변하지 않았다. 여러종류의 염용액으로 침출한 K, Al, Na및 S 등의 이온은 모두 $Bg_2$와 $Bg_3$층에 많이 분포하여 Jarosite 광물의 형성을 확인할 수 있었다.

• Geomechanics and Engineering
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• 제12권3호
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• pp.483-503
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• 2017

Uncertainty is a fact belonging to engineering practice. An important uncertainty that sets geotechnical engineering is the variability associated with the properties of soils or, more precisely, the characterization of soil profiles. The reason is due largely to the complex and varied natural processes associated with the formation of soil. Spatial variability analysis for the study of the stability of natural slopes, complementing conventional analyses, is able to incorporate these uncertainties. In this paper the characterization is performed in back-analysis for a case of landslide occurred to verify afterwards the presence of the conditions of shear strength at failure. This approach may support designers to make more accurate estimates regarding slope failure responding, more consciously, to the legislation dispositions about slope stability evaluation and future design. By applying different kriging techniques used for spatial analysis it has been possible to perform a 3D-slope reconstruction. The predictive analysis and the areal mapping of the soil mechanical characteristics would support the definition of priority interventions in the zones characterized by more critical values as well as slope potential instability. This tool of analysis aims to support decision-making by directing project planning through the efficient allocation of available resources.

• 한국지하수토양환경학회지:지하수토양환경
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• 제24권6호
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• pp.26-32
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• 2019

An analysis of groundwater quality is significant for monitoring and managing water contamination and groundwater system. For the purpose of those, the geochemical characteristics of groundwater were studied over the concern for water quality, water type and origin of nitrate nitrogen. Total colony counts were detected in 11 out of 20 samples, and the average value was 31.73 CFU/ml. Range and average of NO₃-N concentrations were 0.9~24.0 mg/L and 8.3 mg/L. All groundwater types were found to be Ca²⁺-HCO₃^-. The range and average of NO₃-N were 0.2~17.4 mg/L and 8.7 mg/L, and those of δ¹⁵N were 1.7~8.9‰, and 5.0‰. Careful consideration is required for evaluating the origin of nitrogen when NO₃-N concentration is low. In general, noticeable difference between rockbed and alluvial water was not found. The ranges of nitrate origins by chemical fertilizer, livestock manure and domestic sewage, and natural soil were 29.6~76.4%, 14.2~58.9% and 2.6~7.0%, and the average values of those were 57.4%, 37.4%, and 5.3%, respectively. Origin of nitrate was affected by more chemical fertilizer than the other parameters. Rockbed water was more affected by chemical fertilizer than alluvial water.

• 한국구조물진단유지관리공학회 논문집
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• 제11권1호
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• pp.163-170
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• 2007

본 연구에서는 개발한 Chemical Compaction Pile(이하 CCP)공법의 연약지반 개량의 적용성을 평가하기 위하여 모형 아크릴 토조와 CCP 전용 토조를 제작하였으며, CCP를 구성하는 주재료인 Bottom Ash, 생석회 및 첨가재의 배합비를 실험변수로 하여 지반의 종류에 따른 함수비, 전단강도의 변화를 측정하였다. 실험결과, 지반의 함수비 감소나 강도증진효과는 생석회의 함유량이 많을수록 크게 나타났으며, 지반개량효과도 짧은 시일 내에 나타나는 것이 확인되었다. 또한, 지반개량에 따른 전단강도의 증진과 함수비의 변화는 지반의 종류에 따라서도 영향을 받는 것으로 나타났다. 그 외에도 개발된 CCP는 충분한 지지력도 확보하고 있어 연약지반개량과 함께 지지말뚝으로써의 기능성이 있는 것으로 평가되었다.