• 한국토양비료학회지
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• 제42권3호
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• pp.160-166
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• 2009

We estimated site productivity for unstocked land based on the relationship between site index (i.e., average height of dominant trees at fixed age) and soil physico-chemical properties of Pinus densiflora stands. Site index relates to a direct method of determining a tree's response to a specific environment such as forest soil and climate conditions. We selected 78 sites in 22 P. densiflora stands of central temperate forest zone, and sampled soils for physicochemical analyzing. And 13 properties of soils were statistically treated by stepwise regression. In the degree of contribution of the variables to site index, the highly effective variables in A horizon were OM, clay content, sand content, available $P_2O_5$, and Exch. $Ca^{{+}{+}}$ inorder, and in B horizon T.N., O.M., Soil pH, cation exchange capacity(C.E.C.), and sand content in order. In both A and B horizon of the soil for P. densiflora stands, the variables commonly contributed to the site index were sand content and OM. These results may be useful to provide not only important criteria for establishment of Pinus densiflora stand sespecially in unstocked land but also aguidance for reforestation.

• 유기물자원화
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• 제7권1호
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• pp.23-30
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• 1999

계분과 돈분퇴비의 연용에 따른 토양의 이화학적 특성을 검토하기 위하여 0~120 Mg/ha 범위의 퇴비를 3년간 연용하였다. 토양의 pH는 시험전 7.1에서 계분 및 돈분퇴비 3년 연용후 6.4~6.9 수준으로 낮아졌으며, 양이온치환용량(CEC)은 퇴비시용에 따라 무비구에 비해 증가하였으나, 연용에 의해 감소되는 경향을 보였다. 치환성양이온함량은 3년 연용후 현저히 증가되었으며, 전기전도도(EC)는 돈분 120Mg/ha 처리구에서 최대 1.25 ds/m 수준까지 높아졌다. 퇴비의 연용에 의해 경도, 용적밀도가 낮아지고, 토색이 짙어져 암갈색을 띠는반면, 공극율은 증가하였다. 계분 및 돈분퇴비를 3년간 연용한 결과 1년, 2년 시용시 돈분퇴비 처리구가 계분 처리구에 비해 토양 중 더 많은 양분축적을 보였으나 3년 연용시에는 큰 차이가 없는 것으로 나타났다.

• Current Research on Agriculture and Life Sciences
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• 제20권
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• pp.39-47
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• 2002

This study was carried out in order to produce useful material for the forest multiple use and forest protection by soil physico-chemical analysis of studied area in Mt. Palgong. The results of soil physico-chemical analysis and statistical analysis represented as following 2 points. 1. Soil depth was in the range of average 61.1 cm and soil texture was loamy sand and sandy loam except Donghwasa area. The part of solid phase and gaseous phase were higher than other areas, but liquid phase was less in verse. Soil water content was in an average 49.5%, penetrability was average $1.95{\times}E^{-2}cm/sec$ and the average of soil hardness was $1.64Kg/cm^2$. This data showed that soil water content, penetrability and soil hardness were good at Mt. Palgong forest soils. 2. Soil pH was the range of 3.4 to 6.0, organic carbon content was 2.8% that is nearly mean of the Korea brown forest soils, total N content is somewhat smaller than that of other places, and total average C/N ratios was 13.9. Average available $P_2O_5$ concentration was 5.05 mg/kg that is lower than that of any others. The concentration of available P of coniferous forests is higher than that of deciduous forests. Exchangeable cations content is similar to those of the Korea brown forest soil and the order of the cation content extent is $Ca^{2+}$ > $Mg^{2+}$ > $Na^+$ > $K^+$.

• 한국지하수토양환경학회지:지하수토양환경
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• 제18권7호
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• pp.18-24
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• 2013

The influences of various operating parameters on physico-chemical techniques were evaluated to remediate petroleum-contaminated sandy soil including S/L ratio, kinetic, and effect of soil particle size. The simple extraction using tap water removed only 20.6% of total petroleum hydrocarbon (TPH), and addition of NaOH enhanced the removal of TPH to approximately 30%. To meet the regulation levels, a surfactant, sodium dodecyl sulfate, was added, and the removal of TPH increased to 4 times. Probably, the carbonate minerals affected chemical aging and soprtion of petroleum, which inhibited the extraction of TPH. The soil with smaller particle size contained more TPH, and the removal of TPH was obstructed with smaller particle size. However, NaOH addition increased the removal of TPH in the smaller particles. The physico-chemical properties of soil influenced greatly the removal of petroleum even in sandy soil.

• Geomechanics and Engineering
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• 제1권4호
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• pp.291-306
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• 2009

One-dimensional soil-column studies were carried out to understand the interaction of three industrial effluents namely amino acid ('highly acidic'), surfactant ('highly organic') and pharmaceutical ('organic and toxic') on the physicochemical behavior, index properties and shear strength of bentonite due to artificial contamination extending to nearly 300 days. Changes in inorganic and organic pollutants present in the effluents due to the interaction of the above effluents and soil were assessed to understand the physico-chemical behaviour. Batch and continuous modes of operation, 8 hrs and 16 hrs Hydraulic Retention Time [HRT] and 25%, 50% concentrations of effluents, were the parameters considered. Amino acid, surfactant and pharmaceutical effluents have shown a high variation in pH (7 to 8) after artificial contamination on bentonite that is their original characteristics of the above effluents have been completely reversed. Further, it is found that the shear strength of bentonite has reduced by about 20%, and with respect to liquid limit and plastic limit shows an increasing trend with time within the period of contamination.

• 한국환경농학회지
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• 제17권2호
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• pp.170-173
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• 1998

신천하수종말처리장에서 발생한 슬러지를 처리별로 시용한 다음 토양의 이화학성(理化學性)과 중금속 함량변화를 조사하였다. 슬러지 시용량이 증가함에 따라 질소, 인산 및 무기염류의 함량이 증가하는 것으로 나타 났으며, 토양의 입단화, 공극률 및 투수성이 증가하였으며 경도는 감소하였다. 중금속 함량은 Cr, Zn의 경우 약간의 증가를 보였으며,함류량이 적어 시용량이 증가하여도 함량에 차이가 없으며, 하층으로 이동하거나 용탈하지 않는 것으로 나타났다. Sludge중 중금속 함량이 매우 낮음으로 sludge의 처리가 토양 중금속 함량에 별다른 영향을 주지 않았다.따라서 토양의 하부(下部)로 이동하는 현상도 나타나지 않았다.

• 한국환경보건학회지
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• 제23권1호
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• pp.1-7
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• 1997

We investigated the influence of various known sterilization methods on atrazine assimilation. The present study was designed to investigate the effect of autoclaving, sodium azide and mercuric chloride treatment on the assimilation of atrazine in soil and sediment. The sterilization reactor treated with sodium azide resulted in $^{14}CO_2$ generation and atrazine was rapidly disappeared from reactor through chemical reaction with sodium azide. These findings seem to indicate that sodium azide sterilization is not recommended for atrazine studies. In sample reactors autoclaved or treated with mercuric chloride, $^{14}CO_2$ generation was not detected and most of the disappeared atrazine was found to exist as hydroxyatrazine. These results suggested that autoclaving or mercuric chloride treatment could be effective sterilization methods. However, chemical properties(pH and redox potential) of soil and sediment were altered by any of the sterilization methods applied. So it was suspected that these altered properties could affect distribution and mineralization of atrazine in soil and sediment. In addition, both autoclaving and mercuric chloride treatment have altered $K_d$ values of hydroxyatrazine more significantly than those of atrazine. Consequently, although autoclaving and mercuric chloride treatment are effective sterilization methods, one must be careful in using them in practice as these methods may cause chemical degradation of both of atrazine and its metabolites and changes in chemical properties of soil and sediment. In conclusion, careful assessment of sterilization methods must be made for the degradation studies of chemicals in soil and sediment in order to minimize possible undesirable chemical degradation of sample and/or changes in physico-chemical properties of soil and sediment by the selected sterilization methods.

• 한국토양비료학회지
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• 제30권1호
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• pp.62-66
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• 1997

논토양에 대한 전산화(電算化)된 정밀토양조사자료(精密土壤調査資料)를 이용(利用)하여 논토양(土壤) 유형별(類型別) 13개(個) 물리화학적인 특성의 평균치(平均値)를 구하고 토양개량(土壤改良)에 대한 기초자료(基礎資料)를 제공하고자 전산자료를 분석, 검토한 결과는 다음과 같다. 1. 논토양 B층위(層位)에서의 점토함량은 보통답(普通畓)이 28.3%, 사질답(砂質畓)이 11.8%, 미숙답(未熟畓)이 26.8%이었으며 토양 pH는 습답(濕畓), 특이산성답(特異酸性畓)을 제외하고는 B층(層)이 A층(層)보다 높았다. 2. 보통답중(普通畓中)에서 하천변(河川邊)논 A, B층의 점토함량은 각각 16.8%, 23.1%로 가장 낮았고 유기물함량은 42g/kg, 18g/kg로 가장 많았으며 유효인산함량도 가장 많았다. 3. 논토양 유형별(類型別) B층(層)의 유기물함량수준별 분포비율(分布比率)은 사질답, 미숙답은 10g/kg 이하가 가장 많고 특이산성답을 제외한 각 답유형에서는 10~20g/kg 범위가 가장 많았다. 4. 보통답(普通畓) B층위(層位)에서 물리화학성 상호간의 상관계수(相關係數)는 전부 1~5% 수준내에서 유의성(有意性)이 높았다.

• 한국토양비료학회지
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• 제49권4호
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• pp.347-354
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• 2016

This study was conducted to investigate the physical and chemical properties of soils in Saemangeum reclaimed lands. The investigated areas were total 5,020 ha which included 220 ha for Agricultural Life site, 2,450 ha for Tourism & Leisure site, 1,130 ha for Industrial & Research site, 820 ha for Bioenergy crop production site, and 400 ha for Rural City site. Soil samples consisting of the upper 20 cm from the surface were collected in every $200m{\times}500m$ of the each site in March and September, 2015. Particle size distribution of soils in the reclaimed land was 83.2% sand, 8.6% silt and 8.2% clay in average. Soil texture was distributed as 40.8% sandy soil, 35.5% loamy sand, and 19.7% sandy loam. Based on the investigation of soil chemical properties conducted in March, 2015, soil pH, electrical conductivity of a saturated soil paste extract (ECe), and exchangeable (Exch.) $K^+$ and $Mg^{2+}$ concentrations were higher than those of the optimum levels for upland soil, whereas soil organic matter content, available (Avail.) phosphate concentration, and Exch. $Ca^{2+}$ concentration were lower than those of the optimum ranges. Depending on the results of the soil chemical properties measured in September, 2015, soil pH, ECe, and Exch. $K^+$ concentration were higher than those of the optimum levels, but soil organic matter, Avail. phosphate, and Exch. $Ca^{2+}$ concentration were lower than the optimum ranges. In addition, distribution of sodic soil ranged between 41.4% and 50.0%, and saline soils were from 16.4 to 31.8%. Soils with pH values above 7.0 increased from 15.3% in March to 35.2% in September. Soils with ECe values over $4.8dS\;m^{-1}$ increased from 45.6% to 50.7%, whereas soils with the values below $2.0dS\;m^{-1}$ decreased from 42.8% to 36.9%.

• 한국환경농학회지
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• 제31권1호
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• pp.75-95
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• 2012

BACKGROUND: Increase of heavy metals in agricultural ecosystem has become a social issue nationwide as it is related to public health. This review was performed to find out more systematic and integrated future researches on heavy metals using up to date articles published in the Korean journals related to agricultural environment. METHODS AND RESULTS: Researches on heavy metals in agricultural soils and plant uptake were categorized by the establishment of criteria, analytical methods, monitoring, management of source, characteristics and behavior in soil, plant uptake, bioavailability affecting physico -chemical properties in soil, risk assessment and soil remediation. In the early 1990s, the monitoring for heavy metals in soil has been widely performed. Accumulation of heavy metals in contaminated soil and availability to plants has also attracted interests to study the soil remediation using various physico-chemical methods. The phytoavailability and phytotoxicity of heavy metals have been mainly studied to assess the safety of agro-products using risk assessment techniques in the 2000s. CONCLUSION: Future direction of research on heavy metal in agricultural environment must be carried out by ensuring food safety and sustainability. A steady survey and proper management for polluted regions should be continued. Law and regulation must be modified systematically. Furthermore, studies should expand on mitigation of heavy metal uptake by crops and remediation of polluted fields.