• 한국토양비료학회지
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• 제43권6호
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• pp.1008-1011
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• 2010

A method currently used to determine soil organic matter (SOM), Tyurin method, is time consuming and expensive while accurate. Recently, a spectrophotometric determination was reported to be rapid, accurate, stable, easy to execute, and amendable to field use for soil samples obtained from Texas, USA. The objective of this study was to test if the spectrophotometric method is applicable to soils in Korea. Soil organic matter was extracted by 1 M HCl followed by a 0.25 M NaOH-0.1 M sodium pyrophosphate solution at a ratio of 1:250 soil:extractant. Soil organic matter determined by Tyurin method was linearly related to the value based on absorbance at 300 nm of the soil extracts with a coefficient of determination ($r^2$) of 0.81. Therefore, the result imply that this spectrophotometric method can be used to determine the soil organic matter of agricultural soils in Korea.

• Journal of Forest and Environmental Science
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• 제32권1호
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• pp.20-26
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• 2016

DTPA (Diethelene-triamine pentaacetic acid) extractable micronutrients of surface soil samples from six different locations of Cox's Bazar and Chittagong districts were studied. All the soils under study were sufficient in DTPA extractable Fe, Mn and Cu contents. The available Zn contents in soils of Dulhazara, Chengchhari and Faissakhali under study were also above the critical limit while soils at Fulchhari, Hasnabad and CU were deficient in available Zn. The study also showed that DTPA extractable Fe content had the significant and positive relationships with clay and soil organic carbon. On the hand, negative and significant relationship was observed between extractable Mn and soil pH while DTPA extractable Zn and Cu were positively and significantly correlated with soil organic carbon of the studied area.

• Animal cells and systems
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• 제4권1호
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• pp.57-62
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• 2000

Soil samples were collected in thirteen Manitoba boreal forest sites. Spatial distribution of chytrids from diverse boreal forest microhabitats was investigated by baiting with jack pine pollen. After baiting, the pollen was surveyed for chytrids for 8 ten day period and individual species were counted. Total infestations of pollen by chytrids ranged from 5.8% to 90.2% from various soils. Each site with high infestation was characterized by litter with high needle content while mineral soil or soil with limited organic matter yielded low levels of pollen infestation. Species diversity tended to be higher in soils with higher pollen infestation and lower in soils with lower pollen infestation. Lower diversity was generally observed in mineral soils or soils with a limited organic horizon comprised, in part, of broad leaf litter. Based on coefficients of association and species in common among species across the collection sites, it was possible to relate dominant species assemblages in site groups. These species assemblages in the site groups suggest that the chytrids are distributed by litter and soil types. It can be concluded that the substratum characteristics of litter types and availability of litter may be important in describing chytrid distribution in boreal forest sites.

• 한국토양비료학회지
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• 제46권1호
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• pp.65-72
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• 2013

This study was carried out to understand the long-term effects of organic waste treatments on the fate of heavy metals in soils originated from the organic wastes and consequent uptake of heavy metals by plant, together with examination of changes in soil properties and plant growth performance. In this study, the soils treated with three different organic wastes (municipal sewage sludge, alcohol fermentation processing sludge, pig manure compost) at three different rates (12.5, 25.0, 50.0 ton $ha^{-1}yr^{-1}$) for 7 years (1994 - 2000) were used. To see the long-term effect, plant growth study and soil examination were conducted twice in 2000 and 2010, respectively. There was no additional treatments of organic wastes for 10 years after the organic waste treatment for 7 years. Compared to plant growth examination conducted in 2000 using radish (Raphanus sativus cv. sodamaltari), it appeared that height, root length and diameter, fresh weight of radish grown in 2010 decreased in the plots treated with municipal sewage sludge and alcohol fermentation processing sludge and that the extent of decrease was higher with increase of sludge application rates. On the other hand, pig compost treatment increased plant height, root length and diameter, fresh weight with increasing application rates. Cu and Pb concentrations in radish root and leaves increased in 2010 compared to those in 2000 while Ni concentrations in root and leaves decreased. Zn concentration was increased only in the soils treated with pig manure compost. Multiple regression analysis among heavy metal species fractions in soils, soil pH, and metal concentrations in radish root and leaves indicated that the metal uptake by radish was governed mainly by the soil pH and subsequent increase of available heavy metal fractions in soils with organic waste treatments.

• 한국환경과학회지
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• 제27권7호
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• pp.561-575
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• 2018

Agricultural soils around springwaters heavily affected by pesticide run-off and around wells considering the regional characteristics were collected at 24 stations in Jeju Island, and the physicochemical properties and adsorption and leaching characteristics of four nonionic pesticides (diazinon, fenitrothion, alachlor, and metalaxyl) were investigated. The values of the major soil factors affecting the adsorption and leaching of pesticides, namely, soil pH($H_2O$), organic matter content, and cation exchange capacity (CEC), were in the range of 4.64 ~ 8.30, 0.9 ~ 13.1% and 12.7 ~ 31.7 meq/100 g, respectively. The Freundlich constant, $K_F$ value, which gives a measure of the adsorption capacity, decreased in the order of fenitrothion > diazinon > alachlor > metalaxyl, which was identical to their lower water solubility. Among the collected soils, the $K_F$ value was very highly correlated with organic matter content ($r^2=0.800{\sim}0.876$) and CEC ($r^2=0.715{\sim}0.825$) and showed a high correlation with clay content ($r^2=0.473{\sim}0.575$) and soil pH($H_2O$) ($r^2=0.401{\sim}0.452$). The leaching of pesticides in the soil column showed a reverse relationhip with their adsorption in soils, i.e., the pesticides leached more quickly for the soils with lower values of organic matter content and CEC among the soils and for the pesticides with higher water solubility.

• 한국환경농학회:학술대회논문집
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• 한국환경농학회 2011년도 30주년 정기총회 및 국제심포지엄
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• pp.177-187
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• 2011

This study was conducted to determine some physical and chemical properties of the soil and their relationship to spectroscopic-based (visible range) analytical methods while evaluating soil organic matter fractions and soil quality in degraded and non-degraded soils in a wide range of environments. Soil samples were collected from the different landscape positions of cultivated and noncultivated soils, and the latter from the same landscape positions but with different vegetation, at Songco, Lantapan, Bukidnon. The physical and chemical properties of the soils were determined at the SPAL, CMU, Musuan, Bukidnon while the metagenomic properties were determined at the Laboratory of the University of Missourri, Missourri, USA. Bulk density and air dry soil strength values of the soils from the cultivated areas were generally higher than those of the uncultivated areas. Also, soils at the summit generally had lower bulk density and soil strength values than the other landscape positions. Moreover, soils planted to camote (Ipomoea batatas) had higher bulk density and soil strength values compared to soils grown to pepper under the trees. Exchangeable calcium (Ca), magnesium (Mg), and potassium (K) and cation exchange capacity (CEC) of the soils were generally higher in uncultivated areas than those of the cultivated areas. A similar trend was observed for the potassium permanganate ($KMnO_4$)-oxidizable organic C contents determined by spectroscopic method and the total C contents determined by the Walkley-Black method. The $KMnO_4$-oxidizable organic C contents determined by spectroscopic method and the total C contents determined by the Walkley-Black method were closely related ($r=0.631^{**}$). Hence, the former method shows promise in assessing soil quality as it is a rapid test, relatively low cost and can be distributed as a field kit either with a portable spectrometer or with a color chart.

• 한국토양비료학회지
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• 제44권2호
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• pp.242-247
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• 2011

경남지역 밭 토양 25개소를 대상으로 2009년에 토양 화학성분과 미생물 다양성을 검토하고 토성, 지형 및 작물별 주요 변동요인을 주성분분석으로 해석하였다. 토양 유효인산 및 치환성 칼륨과 칼슘 함량은 적정수준 보다 높았으며 대부분의 토양 화학성분이 최소값과 최대값의 차이가 크게 나타났다. 지형적으로 산록경사지는 토양 유기물 함량과 치환성 칼륨 함량이 유의적으로 높았고 (p<0.05) 토성별 유기물 함량은 양토에서 높은 반면에 염류농도와 유효인산 함량은 사양토에서 높았으며 고구마 재배지의 치환성 칼슘함량은 감자 재배지에 비해 유의적으로 높았다. 지형별 밭토양의 곰팡이 개체수는 곡간 및 선상지가 하성평탄지 보다 유의적으로 많았고 토양 미생물체량과 탈수소효소 활성은 산록경사지가 다른 지형에 비해 유의적으로 높았다 (p<005). 토성에 따른 토양의 coliform 그룹은 미사질양토가 사양토와 양토에 비해 유의적으로 높았고 미생물체량은 양토가 미사질양토 보다 유의적으로 높았으나 (p<005) 작물별 미생물상과 토양 미생물체량 및 탈수소효소 활성은 유의적인 차이가 없었다. 주성분 분석결과 제1주성분이 32.2%, 제2주성분이 24.2%로서 전체 56.4%의 자료를 설명할 수 있었으며 제1주성분은 토양의 유효인산 함량이 가장 크게 기여하였다. 토양 바실러스균과 곰팡이균은 토양의 유기물 함량과 정의 상관관계를 보였으며 토양 pH는 형광성 슈도 모나스균과 정의 상관관계를 나타냈다.

• 한국토양비료학회지
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• 제11권4호
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• pp.247-262
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• 1979

Majority of reclaimable soils in hillside lands in Korea are red yellow soils, with exception in Jeju island, where most of reclaimable hillside lands are composed of volcanic ash soils. Songjeong, Yesan and Samgag series are the major soil series of red yellow soils which are available for the reclamation. When observed in the fields, they are distinguished as reddish brown clay loam, red yellow sand loam and yellowish brown sand loam. They have moderately good physical properties but their chemical properties are generally poor for crop cultivations. The chemical properties of red yellow soils, as compared to long time cultivated (matured) soils, are characterized by very low pH, high in exchangeable Al content and phosphorus fixation capacity. Also extraodinary low available phosphorus and organic matter contents are generally observed. On the other, the chemical properties of volcanic ash soils are characterized by high armophous Fe and Al hydroxides and organic matter contents, which are the causative factors for the extremely high phosphorus fixation capacity of the soils. The phosphorus fixation capacity of volcanic acid soils are as high as 5-10 times of that of red yellow soils. Poor growth of crops on newly reclaimed red yellow soils are mainly caused by very low available P and pH and high exchangeable Al. Relatively high P fixation capacity renders the failure of effective use of applied P when the amount of application is not sufficient. Applications of lime to remove the exchangeable Al and relatively large quantity of P to lower the P fixation capacity and to increase the available P are the major recommendations for the increased crop production on red yellow hillside soils. Generally recommendable amounts of lime and P to meet the aforementioned requirements, are 200-250kg/10a of lime and $30-35kg\;P_2O_5/10a$. Over doses of lime. frequently induces the K, B, arid Zn deficiencies and lowers the uptake of P. In volcanic ash soils, it is difficult to alter the exchangeable Al and the P fixation capacity by liming and P application. This may be due to the peculiarity of volcanic ash soil in chemical properties. Because of this feature, the amelioration of volcanic ash soils is not as easy as in the case of red yellow soils. Application of P as high as $100kg\;P_2O_5/10a$ is needed to bring forth the significant yield response in barley. Combined applications of appropriate levels of P, lime, and organic matter, accompanied by deep plowing, results in around doubling of the yields of various crops on newly reclaimed red yellow soils.

• 한국농공학회논문집
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• 제48권1호
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• pp.3-10
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• 2006

The chemical fractions of heavy metals were investigated in the soils of reclaimed and natural tidelands of southwest coastal area of Korea. The distribution pattern of each heavy metal in different fractions was in the order: 1) Cu : organic bound > organic complex > residual > exchangeable = water soluble. 2) Cr : residual > organic bound > organic complex > water soluble > exchangeable. 3) Pb : organic bound > residual > organic complex > water soluble > exchangeable. 4) Cd residual > organic bound > organic complex > water soluble = exchangeable. 5) Zn : organic bound > residual > organic complex > water soluble > exchangeable. The content of residual Zn showed positive correlation with organic matter content but organic bound Zn showed negative correlation with CEC. The content of residual and exchangeable Cd showed highly positive correlation with organic matter content but residual, organic bound, and exchangeable Cd showed negative correlations with CEC. Water soluble Pb showed positive correlation with CEC but organic bound Pb showed negative correlation with CEC.

• 농업과학연구
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• 제43권4호
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• pp.634-640
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• 2016

The objective of this study was to evaluate the effectiveness of using HR-GC/MS for the rapid screening of dieldrin residues in soils. Persistent organic pollutants (POPs) of organochlorine pesticides such as dieldrin, were analyzed in sedimentary rock and granite rock collected from greenhouses, Niigata, Japan. Dieldrin remains in Japanese farming soils, more than 40 years after their use as insecticides was prohibited. The averages in soil moisture ranged from 2.79% to 7.20% in soils derived from sedimentary rock and from 25.59% to 31.40% in soils derived from granite rock. Mean concentrations of dieldrin residues in sedimentary rock and granite rock were $39.7ng\;g^{-1}$ and $40.51ng\;g^{-1}$, respectively. Dieldrin residue was detected at a slightly higher concentration in granite rock than sedimentary rock samples. There was no consistency between the two soils or between surface and subsurface soils. The coefficients of variation of the two soils were 10.6% and 8.7%, respectively. These results suggest that our high-resolution mass spectrometry detector (HR-GC/MS) is effective at analyzing residual organochlorine pesticides in soil. In order to increase the precision and sensitivity for chemical analysis of POPs, high-resolution gas chromatography coupled with a HR-GC/MS is highly recommended.