• 한국토양비료학회지
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• 제45권6호
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• pp.920-924
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• 2012

This study was performed to estimate total contents of arsenic (As) by stepwise multiple-regression analysis using chemical properties and extractable contents of metal in paddy soil adjacent to abandoned mines. The soil was collected from paddies near abandoned mines. Soil pH, electrical conductively (EC), organic mater (OM), available phosphorus ($P_2O_5$), and exchangeable cations (Ca, K, Mg, Na) were measured. Total contents of As and extractable contents of metals were analyzed by ICP-OES. From stepwise analysis, it was showed that the contents of extractable As, available phosphorus, extractable Cu, exchangeable K, exchangeable Na, and organic mater significantly influenced the total contents of As in soil (p<0.001). The multiple linear regression models have been established as Log (Total-As) = 0.741 + 0.716 Log (extractable-As) - 0.734 Log (avail-$P_2O_5$) + 0.334 Log (extractable-Cu) + 0.186 Log (exchangeable-K) - 0.593 Log (exchangeable-Na) + 0.558 Log (OM). The estimated value in total contents of As was significantly correlated with the measured value in soil ($R^2$=0.84196, p<0.0001). This predictive model for estimating total As contents in paddy soil will be properly applied to the numerous datasets which were surveyed with extractable heavy metal contents based on Soil Environmental Conservation Act before 2010.

• 한국환경농학회지
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• 제17권4호
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• pp.362-367
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• 1998

사양토, 양토, 식양토의 3가지의 토양을 2' column에 충진한 후 인공 산성비( pH 2.0, 4.0, 6.0) 1200㎜를 처리하여 산성비의 토양내 침투수량에 따른 토양 중 무기양분의 이동 양상과 토양내에서의 환경변화에 대한 시험 결과, 산성비의 토양침투에 따른 토양의 pH 변화는 산성비의 pH가 4.0가 6.0에서는 별 차이가 없었으나 pH2.0에서는 토심별로 큰 차이를 보였으며, pH감소는 사양토> 양토> 식양토 순위였다. 산성비의 토양침투에 따른 토양의 토심별 치환성과 수용성 염기의 용탈양은 Ca> Mg> K 순위였으며, 산성비의 pH2.0에서 가장 많은 양이 이동하였다. 이들 염기들의 평균이동거리를 pH2.0의 산성비 처리에서는 사양토, 양토, 식양토 공히 Mg> Ca> K의 순위였으나, 산성비의 pH4.0인 경우 사양토와 식양토는 Mg> K> Ca, 양토의 경우는 K> Mg> Ca의 순위였다. 인산의 경우 평균 이동거리는 다른 성분에 비하여 매우 짧았으며 산성비의 산도가 증가할수록 증가하였고, 일반 강우 조건에서는 거의 이동하지 않았다.

• Journal of Forest and Environmental Science
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• 제33권3호
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• pp.172-186
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• 2017

The effects of application of fuel-reduction treatment in wildfire management has not been tested in dry forests of Ghana. Therefore, the short-term ecological effects of prescribed burning and hand thinning treatments followed by experimental wildfire were investigated in degraded forests and Tectona grandis forest plantations in two forest reserves of different levels of dryness in Ghana. The results showed that more trees were killed in prescribed burning (average of 41% in degraded forest and 18% in plantations) than hand thinning (7.2% in degraded forests and 8% in plantation). More tree seedlings were also killed in prescribed burning (72%) than hand thinning (47%). The mortality of trees and seedlings were greater in Worobong South forest, a less dry forest reserve than the Afram Headwaters forest, a drier forest reserve. Fuel treatment especially prescribed burning compared to the control reduced wildfire effects on forest canopy particularly in the less dry forest and tree mortality especially in the drier forest. Prescribed burning temporarily increased pH, exchangeable potassium (52%) and available phosphorus (82%) in the surface soils of the entire plots. The two fuel treatment methods did not have much influence on basal area, organic matter and total nitrogen. Nevertheless, they were able to reduce the adverse wildfire effects on soil pH, exchangeable potassium, available phosphorus, organic matter and total nitrogen concentrations. Fuel treatments therefore have potential application in dry forest management in Ghana due to their ability to retain important forest ecological traits after a wildfire incidence.

• 한국응용곤충학회지
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• 제21권2호
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• pp.68-72
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• 1982

인삼 재배포장에서 병원균인 Fusarium spp.의 밀도와 근부에 영향을 미치는 토양환경요인을 조사하였다. 2년근 포장의 토양을 토성별로 분류하여 결주율, Fusarium spp. 밀도, 화학적 성질을 비교해 본 결과 점토 함량이 들었고 결주율과 질산태 질소는 줄어드는 경향이었으며 다른 성질은 뚜렷한 차이가 없었다. 6년근 포장에서는 근부율과 유효인산 함량이 정의 상관(r=0.3162, p=0.05)을 보였으며 Fusarium spp. 밀도와 Streptomyces spp. 밀도는 고도의 부의 상관(r=-0.3976, p=0.01)을 나타내었다.

• 한국토양비료학회지
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• 제48권5호
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• pp.549-555
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• 2015

Objective of this study was to investigate the effect of carbonized biomass from crop residues on chemical properties of soil and soil carbon pools during soybean cultivation. The carbonized biomass was made by field scale mobile pyrolyzer. A pot experiment with soybean in sandy loam soil was conducted for 133 days in a greenhouse, by a completely randomized design with three replications. The treatments consisted of four levels including the control without input and three levels of carbonized biomass inputs of $9.75Mg\;ha^{-1}$, C-1 ; $19.5Mg\;ha^{-1}$, C-2 ; $39Mg\;ha^{-1}$, C-3. Soil samples were collected and analyzed pH, EC, TC, TN, inorganic-N, available phosphorus and exchangeable cations of the soils. Soil pH, Total-N and available phosphorus contents correspondingly increased with increasing the carbonized material input. The contents of soil carbon pools were $19.04Mg\;C\;ha^{-1}$ for C-1, $26.19Mg\;C\;ha^{-1}$ for C-2, $33.62Mg\;C\;ha^{-1}$ for C-3 and $12.01Mg\;C\;ha^{-1}$ for the control at the end of experiment, respectively. Increased contents of soil carbon pools relative to the control were estimated at $7.03Mg\;C\;ha^{-1}$ for C-1, $14.18Mg\;C\;ha^{-1}$ for C-2 and $21.62Mg\;C\;ha^{-1}$ for C-3 at the end of experiment, respectively, indicating that the soil carbon pools were increased with increasing the input rate of the carbonized biomass. Consequently, it seems that the carbonized biomass derived from the agricultural byproducts such as crop residues could increase the soil carbon pools and that the experimental results will be applied to the future study of soil carbon sequestration.

• 한국토양비료학회지
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• 제44권3호
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• pp.510-516
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• 2011

Salt-affected soils are present in Pakistan in significant quantity. This experiment was conducted to assess the effectiveness of compost for reclamation and compare its efficiency with gypsum. For this purpose, various combinations of compost and gypsum were used to evaluate their efficacy for reclamation. A saline-sodic field having $pH_s$ 8.90, $EC_e$ $5.94dS\;m^{-1}$ and SAR $34.5(mmol\;L^{-1})^{1/2}$, SP (saturation percentage) 42.29% and texture Sandy clay loam, gypsum requirement (GR) $8.75Mg\;ha^{-1}$ was selected for this study. The experiment comprised of seven treatments (control, gypsum alone, compost alone and different combinations of compost and gypsum based on soil gypsum requirements). Inorganic and organic amendments (gypsum and compost) were applied to a saline sodic soil. Rice and wheat crops were grown. Soil samples were collected from each treatment after the harvest of both crops and analyzed for chemical properties (electrical conductivity, soil reaction and sodium adsorption ratio) and fertility status (organic matter, available phosphorus and potassium contents) of soil. Results of this study revealed that compost and gypsum improved chemical properties (electrical conductivity, soil reaction and sodium adsorption ratio) of saline sodic soil to the desired levels. Similarly, all parameters of soil fertility like organic matter, available phosphorus and potassium contents were built up with the application of compost and gypsum.

• Journal of Plant Biology
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• 제7권1호
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• pp.5-10
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• 1964

The effects of briquette ashes on the growth of vegetable (cabbage, lettuce, spinach and radish) and their fresh weight under the culture of the soil mixed with the briquette ashes, and on the chemical properties of the soil were investigated. The growth rate of these palnts and chemical properteis of the soil has shown some influence due to different concentration of briquette ashes added to the soil. The increase of growth in cabbage and lettuce was remarkably found by the plot treated with 1/50 concentration of briquette ashes. The fresh weight of vegetable plants was increased with high concentration of briquette ashes, but if the concentration of briquette ashes was too high, it was rather depressed. Chemical properties in the soil after cultivation of the plants were more depressed than before cultivation. In contrast the available nitrogen content in the soil after cultivation was more increased than before cultivation of the plants. The reduction of available nitrogen and nitrate nitrogen was associated with the increasing intensity of briquette ashes, but available phosphorus content was increased with high concentration of briquette ashes, though its content was not so high as the results obtained by Han(8). The values of total exchangeable base and pH in the soils treated with briquette ashes were increased with a high degree of the concentration of ashes. The value of pH was not significant, and pH value of lime plots was higher than that of briquette ashes. The average value of the water content did not show any difference, and the difference of the content of organic matter in the soil in which different vegetable grew into the plots reached to the significance of a 5% level.

• Applied Biological Chemistry
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• 제9권
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• pp.111-118
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• 1968

제주도(濟州道 ) 목야조성지(牧野造成地)의 흑색(黑色) 및 적색화산회토양(赤色火山灰土壤)에 대(對)한 7개목초(個牧草)의 토양인산(土壤燐酸) 이용력(利用力)을 $P^{32}$를 사용(使用)하여 조사(調査)하고 토양(土壤)의 각종(各種) 유효(有效) 인산(燐酸) 및 형태별(形態別) 분별정량(分別定量)을 하여 알맞은 유효인산(有效燐酸) 정량법(定量法)을 찾고자 하였던바 다음과 같은 결과(結果)를 얻었다. 1) 목초별(牧草別) 토양인산(土壤燐酸) 이용력(利用力)은 Italian rye grass${\gg}$ Soybean> cassia> corn> weeping love grass${\gg}$ Korean Lespedeza> Red Clover의 순(順)이며 A-value$(kgP^{2}O^[5}/ha)$가 1000이상(以上) $200{\sim}500$과 40이하(以下)의 세 가지로 대별(大別)된다. 2) 흑색토양(黑色土壤)은 적색토양(赤色土壤)에 비(比)해 무기인산(無機燐酸)이 배(培)가 되지만 목초(牧草)가 흡수(吸收)하는 유효인산량(有效燐酸量)에는 차이(差異)가 없음으로 유효(有效) 인산추출액(燐酸抽出液)은 두 토양(土壤)에 동량(同量)으로 추출(抽出)되는 것이라야 한다. 3) 목초별(牧草別) 흡수이용력(吸收利用力)에 맞는 유효인산추출액(有效燐酸抽出液)은 원토건중당(原土乾重當) 최고(最高) 20 ppm을 침출할 수 있는것과 최소(最小) 100 ppm 이상(以上) 추출(抽出)할 수 있는 두 개의 추출제(抽出劑)가 추정(推定)되며 전자(前者)는 이용력(利用力)이 약(弱)한 목초(牧草)에 후자(後者)는 이용력(利用力)이 강(强)한것에 적용(適用)되고 전자(前者)는 Truog 법(法)이 사용(使用)될 수 있으나 후자(後者)는 해당(該當)한 추출법(抽出法)은 사용(使用)된것들 중(中)에는 없었다. 4) 두과목초(荳科牧草)는 T/R 치(値)와 pdF(비료(肥料)에서 유래(由來)한 식물체무백분비(植物體燐百分比)간(間)에 5% 수준(水準)에서 부상관(負相關)이 있고 T/R가 5이상(以上)에서 50% 이하(以下)의 %pdF를 T/R가 5 이하(以下)에서 80% 이상(以上)의 %pdF를 보였으나 화본과(禾本科)에서는 아무런 상관(相關)이 없었다.

• Applied Biological Chemistry
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• 제32권2호
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• pp.109-115
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• 1989

퇴비(堆肥) 및 비료(肥料) 시비방법별(施肥方法別)로 무비구외(無肥區外) 7처리(處理)로 21년간(年間) 시험한 미사식양질계(微砂埴壤質系) 보통답(普通畓)에서 urease, L-glutaminase, phosphatase 활성(活性)을 조사하였다. 총(總) urease 활성(活性)(TUA)과 미생물(微生物) 분필(分泌) urease 활성(活性)(MUA)은 처리간(處理間)에 차이가 심하였으나, 토양(土壤)에 축적(蓄積)된 urease 활성(活性)(AUA)은 처리간(處理間)에 차이가 경미(輕微)하였다. 특히 MUA는 3요소(要素)와 퇴비(堆肥), 3요소(要素)와 규산(硅酸) 시용구(施用區)에서 가장 높았으며 토양중(土壤中) 인산(燐酸), 가리(加里), 규산(硅酸) 함량(含量)과도 고도(高度)의 유의(有意)한 상관관계(相關關係)가 있었다. 총(總) L-glutaminase 활성(活性)(TGA)과 토양(土壤)에 축적(蓄積)된 L-glutaminase 활성(活性)(AGA)은 처리 간에 차이가 심하였으나, 미생물(微生物) 분필(分泌) L-glutaminase 활성(活性)(MGA)은 처리간에 차이가 경미(輕微)하였으며 활성정도(活性程度)는 AGA와 비슷하였다. 또한 AGA는 토양 중 규산(硅酸), 인산(燐酸) 함량(含量)과 pH와는 고도(高度)의 유의(有意)한 상관(相關)이 있었다. 토양 중 phosphatase 활성(活性)은 toluene 처리와 무처리간에 차이가 경미하였으나, 퇴비(堆肥)와 비료(肥料) 시비방법(施肥方法)에 따른 차이는 심하여서 3요소구(要素區), 3요소(要素)+퇴비구(堆肥區), 3요소(要素)+규산구(硅酸區)에서 활성(活性)이 높게 나타났다. 그리고 phosphatase 활성(活性)과 토양 PH, 규산(硅酸), 인산(燐酸), 칼슘 함량(含量)과는 유의성(有意性)이 있었다.

• Journal of Plant Biology
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• 제11권3호
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• pp.1-7
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• 1968

Organic matter in rice-paddy soils exercises two antagonistic effects on the rice plant under water-logged conditions in growing season in the course of its decomposition: It liberates mineral nutrients and promotes soil fertility. On the other hand, however, it demands oxygen for its decay and therefore competes with rice roots for this element, when applied in large quantity of fresh status. For the practical end of rice culture, it is most desirable that these two effects should not contend with each other. To determine the proper content of organic materials to be applied, the influences of varied amounts of a homogeneous mixture of dried green manure, ranging from 0 to 20g/pot (1/20,000 tanbo), upon hte growth of rice was investigated in a sand culture. Labeled phosphorus fertilizer was also used in the form of KH232PO4 to evaluate the availability of this nutrient in the soil. Under the present experimental conditions, green mature seems to have influenced little on the growth of rice, except on number of grains produced and grains/straw ratio. Moreover, no sympton of growth inhibition is obsrvable even by the largest amount of its application. The available phosphorus, as estimated by A-value, appears to have increased, as the amount of organic materials applied increases. In view of the fact that pure sand instead of a paddy soil is used in this culture, the present results would not be directly applicable to practical rice farming. Besides, the estimated A-value is in need of further study, since it varies according to method of application, as suggested by Nishigki et. al. (1958).