• 한국토양비료학회지
• /
• 제46권4호
• /
• pp.288-295
• /
• 2013

Nitrogen dioxide ($NO_2$) gas damage on vegetable crops commonly occurs in plastic film houses where relatively large amounts of $NO_3{^-}$ are applied in acid soils. In acid soils, $HNO_2$ can be formed from the $NO_2{^-}$ accumulated during denitrification, and $NO_2$ can be evolved from the chemical self-decomposition of $HNO_2$. In this study, $NO_2$ gas production and its detrimental effects on plants were investigated in soils of various conditions to elucidate the mechanisms involved in the gas production. A silty loam soil was amended with $NO_3{^-}$ (500 mg N $kg^{-1}$) and glucose, and pH and moisture of the soil were adjusted respectively to 5.0 and 34.6% water holding capacity (WHC) with 0.01 M phosphate buffer. The soil was placed in a 0.5-L glass jar with strawberry leaf or $NO_2$ gas absorption badge in air space of the jar, and the jar was incubated at $30^{\circ}C$. After 4-5 days of incubation, dark burning was observed along the outside edge of strawberry leaf and $NO_2$ production was confirmed in the air space of jar. However, when the soil was sterilized, $NO_2$ emission was minimal and any visible damage was not found in strawberry leaf. In the soil where water or $NO_3{^-}$ content was reduced to 17.3% WHC or 250 mg N $kg^{-1}$, $NO_2$ production was greatly reduced and toxicity symptom was not found in strawberry leaf. Also in the soil where glucose was not amended, $NO_2$ production was significantly reduced. In soil with pH of 6.5, $NO_2$ was evolved to the level causing damage to strawberry leaf when the soil conditions were favorable for denitrification. However, compared to the soil of pH 5.0, the $NO_2$ production and its damage to plants were much less serious in pH 6.5. Therefore, the production of $NO_2$ damaging plants might be occurred in acid soils when the conditions are favorable for denitrification.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
• /
• pp.199-202
• /
• 2004

In this study the field-scale tests were performed in which in-situ E/K remediation technologies were applied, and then the results were present. For traditional E/K remediation method the efficiency of remediation is not large, but the enhanced method with citric acid significantly increases the removal efficiency. Also EDTA, reported as a good enhancement agent for removal of heavy metals, is similar to that of citric acid. Therefore citric acid is preferred rather than EDTA in view of the cost on the contaminant removal per unit concentration.

• 한국농림기상학회지
• /
• 제4권1호
• /
• pp.49-57
• /
• 2002

본 연구는 경기도 광주군 퇴촌면 소재 경희대 연습림의 산림토양을 대상으로 인공산성우의 회수별 유입에 따른 산림토양의 완충능에 미치는 영향을 구명하고자 pH 3.0, pH 4.0, pH 5.0 인공산성우를 하루에 1시간 간격으로 10회 유입하여 얻은 결과는 다음과 같다. 각 임지(활엽수, 리기다소나무, 잣나무, 낙엽송)의 토심별(0~15 cn, 15~30 cm) pH를 측정한 결과 모든 임지에서 토심이 깊을수록 토양 pH가 높았다. 또한 각 임지별 염기포화도를 살펴보면 리기다소나무 임지에서 17.42%로 가장 높게 나타났으며 C.E.C는 활엽수임지의 경우 29.87 me/100 g으로 가장 높았다. 인공산성우 회수별 유입 토양용탈수의 pH 변화를 보면 pH 3.0 처리에서 인공산성우 유입회수가 증가함에 따라 초기에는 일시적으로 높아지다가 다시 낮아지는 변곡성을 보였으며, 나머지 pH 4.0과 pH 5.0에서는 토양 용탈수의 pH가 비례적으로 증가하였다. 인공산성우의 pH 수준과 임지에 따라 초기 용탈량은 차이가 있으나 모든 처리에서 인공산성우의 유입회수가 증가함에 따라 염기성 이온의 용탈량은 감소하였다. 또한 pH 5.0 처리에 비하여 pH 3.0과 pH 4.0의 인공산성우 처리에서 총 염기성 양이온의 초기 용탈량이 더 컸으며 이러한 경향은 토양 산성도가 낮고 토양의 염기성 양이온이 높은 임지일수록 뚜렷한 차이를 보였다. 활성 Al의 초기 용탈은 토양 산성도가 높은 지역일수록, 인공산성우의 유입산도가 클수록 높게 나타났다. 또한 토심별로 확인해 본 결과 A층과 AB층간의 Al 용탈량도 소폭의 차이가 있음이 확인되었다. 인공산성우 pH 3.0 처리에서는 모든 임지에서 Al 활성 변화가 정의 관계를 나타내었는데 이는 pH 4.0과 pH 5.0에서의 용탈수와는 반대되는 경향이었으며, 총 염기성 양이온과도 반대되는 경향이 나타났다.

• 한국토양비료학회지
• /
• 제49권2호
• /
• pp.168-180
• /
• 2016

Various researches on the effects of fertilization levels on functional metabolites in crop have been conducted. This review summarizes the previous studies on the relation between fertilization supply and accumulation of metabolites (phenolics, carotenoids, ascorbic acid and glucosinolates) which function as antioxidants in crop. The accumulation of phenolic compounds is related to the activation of phenylalanine ammonia lyase (PAL) in phenylpropanoid pathway. Most of the previous studies discuss that low nitrogen (N) supply activates PAL, thereby increasing the synthesis of phenolics. Similarly, high N supply leads to a decrease in ascorbic acid because of the shading effect derived from the accelerated vegetative growth under high N level. Unlike the phenolics and ascorbic acid, carotenoids are accumulated with increasing N supply. In this regard, the previous studies explain that N is a main element closely associated with formation of key enzyme for the synthesis of carotenoids. Glucosinolates are generally increased under decreasing N supply and increasing S supply. Although the previous studies show similar trends about the accumulation of metabolites by nutrient level, they also suggest that many other factors including crop types, cultivars, cultural environment (water, temperature, light, etc.) influence the accumulation of functional metabolites in crop.

• 한국토양환경학회지
• /
• 제2권3호
• /
• pp.39-47
• /
• 1997

경북 봉화군에 소재한 폐광산인 다덕광산 광미장 및 인근 농경지를 대상으로 금속성분 및 시안의 분포특성과 광미장을 통과하여 방류하는 산성침출수의 생성원인을 파악하였다. 토양오염 공정 시험법에 의한 분석자료에 의하면 광미장 주변의 논 및 밭에서 As이 농경지 토양오염대책 기준인 15mg/kg을 초과하여 광미의 유입에 의해 토양이 오염되는 것으로 나타났다. 광미중에는 As, Cd, Cu, Pb, Zn 및 5 등이 매우 높게 함유된 것으로 나타났고 특히 산화가 진행된 광미장 지표면 부근의 광미에는 이러한 성분들이 용탈되어 산성침출수가 농수로 방류되고 있다. 따라서 토양오염 및 농수로의 오염의 확산 방지를 위해서는 광산주변에 산재하고 있는 광미 및 광미장에 대한환경오염방지 대책이 필요하다고 판단된다.

• 한국환경복원기술학회지
• /
• 제17권1호
• /
• pp.1-12
• /
• 2014

This study was carried out not only to identify the optimum concentrations of sulfur powder and citric acid treated for improving arsenic absorption of Pteris multifuda known as hyperaccumulator of arsenic, but also to develop arsenic purification model in the forest soil. After applying sulfur powder (0, 30, 45, $60g{\cdot}m^{-2}$) and citric acid (0, 200, 400, $800g{\cdot}m^{-2}$) in the forest soil contaminated with heavy metals, P. multifuda was planted and cultivated for 16 weeks. And then the growth and arsenic contents of plants were analyzed. In the result of research, the growth of P. mulifuda, except plant width, cultivated in soils treated with sulfur powder and citric acid was relatively lower than control. The accumulated amount of arsenic in aerial parts of P. multifuda ($1822.2mg{\cdot}kg^{-1}$) cultivated in soils treated with $200g{\cdot}m^{-2}$ citric acid was improved 62.5% against the control. And the accumulated amount of arsenic per 1 $m^2$ ($20.1mg{\cdot}m^{-2}$) was the greatest in $200g{\cdot}m^{-2}$ citric acid treatment. Translocation rate (TR) was higher in all acid treatment compare to control, and was the best in $200g{\cdot}m^{-2}$ citric acid treatment (0.95) especially. It showed that the arsenic absorbed in underground parts was transferred fast to aerial parts. Therefore, $200g{\cdot}m^{-2}$ citric acid treatment in the soil is recommended for arsenic purification using P. multifuda.

• 한국지반공학회:학술대회논문집
• /
• 한국지반공학회 2003년도 봄 학술발표회 논문집
• /
• pp.417-421
• /
• 2003

The purpose of this paper is to study on the construction of roadbed with environmental friendly soil amendment agent. The special amendment agent used in this study is mainly composed of inorganic metal salts such as sodium chloride, magnesium chloride, potassium chloride, calcium chloride,, thus is friendly to the environment, and has a function of soil-cement-agent solidification. Various components of this agent weaken the negative function of humic acid and decompose humic acid itself. Then, the calcium cation of the cement can now be made contact directly to the soil surface. The project of local road demonstration of roadbed construction with special soil treatment agent was peformed in Northeast Thailand on August 1999 by the sponsor of Highway Department of Thailand. A series of field experiments including unconfined compressive strength were carried out to investigate the physical and mechanical characteristics of solidified roadbed treated by this solidifying agent. The results of this research showed that the roadbed using poor soil could be efficiently constructed by treatment of this amendment agent.

• 한국지하수토양환경학회:학술대회논문집
• /
• 한국지하수토양환경학회 2004년도 임시총회 및 추계학술발표회
• /
• pp.211-214
• /
• 2004

MTBE로 오염된 토양에서 생태독성학적 접근 방법으로 3가지 토양 효소의 활성도를 측정해 보았다. MTBE의 잠재적 위험성으로 인한 논란은 계속되고 있으나 토양 오염에 대한 지표로써 토양 효소 활성도의 사용타당성 여부에 대한 실험은 이전에 행해지지 않았다. 따라서 중금속 오염 토양에 대해 좋은 지표로 사용되고 있는 토양 미생물 효소의 활성도를 MTBE에 적용하여 실험해 보았다. 사용한 토양 효소는 Acid Phosphotase, $\beta$-Glucosidase 그리고 Arysulfatase였다. 그러나 실험 결과 MTBE로 오염된 토양의 경우 중금속으로 오염된 토양에 비해 토양 미생물 활성도의 감소가 매우 적었다. 따라서 MTBE의 오염 토양의 경우 본 연구에서 측정된 효소의 활성도는 좋은 지표로 적합하지 않다는 것을 확인했다.

• The Korean Journal of Ecology
• /
• 제21권1호
• /
• pp.1-6
• /
• 1998

Effects of air pollutants on the chemical properties of soil in Yoch'on inductrial complex were investigated. Soil pH showed severe acidity with average value of 4.3$\pm$0.13. Soil pH decreaed along the increase in altitute of Mt. Jeseok. Soil organic matter and total N was 19.2$\pm$3.6% and 4.7$\pm$0.25mg/g, respectively, which were higher than those of unpolluted area, Kongju. Available P was 41.2$\pm$3.7 $\mu$g/g, which was 4 times greater than that of unpolluted area, Kongju. Average content of total-S was 283.5$\pm$14.1 $\mu$g/g, which was 10 times greater than that of unpolluted area. Content of available Al was o.43$\pm$0.03 mg/g, which was 2 times greater than that of unpolluted area. Available Al increased as the soil pH decrease. Contents of exchangeable K, Ca and Mg were significantly lower than those in unpolluted area, because of severe leaching in acid soil.

• 한국토양비료학회지
• /
• 제25권3호
• /
• pp.195-201
• /
• 1992

1. 연세층(現世層)(Holocene deposits)의 선상지(扇狀地) 하부(下部)(Fanbase)에 분포된 육성잠재특이산성토(陸成潛在特異酸性土)는 용천(湧泉)이 산재(散在)되어 있는 배수(排水) 약간불량답(若干不良畓) 조건으로서 토층(土層)에는 7~30%의 석력(石礫)이 있는 식양질(埴壤質) 퇴적토(堆積土)이었다. 2. 잠재특이산성토층(潛在特異酸性土層)은 암회갈색(暗灰褐色)으로서 유기물함량(有機物含量)이 3.3~3.8%로 높았고 치화성(置換性)양이온 함량(含量)이 낮은 반면(反面) 황함량(黃含量)이 0.34~0.41%로 높기 때문에 산화후(酸化後) pH($H_2O$)가 3.4~3.8로 낮았다. 3. 잠재특이산성토층내(潛在特異酸性土層內)의 지하수(地下水)(용정(湧井))중(中)에는 약 80ppm의 $SO_4$와 Na, K, Ca, Mg 등의 ion이 다량함유(多量含有)되어 있었고 지표수(地表水)는 더욱 증발(蒸發), 농축(濃縮)되어 있어 인근(隣近) 하천수(河川水)와는 확연(確然)히 달랐으며 잠재특이산성토층(潛在特異酸性土層)은 용출(湧出)되고 있는 지하수(地下水)에 기인(基因)된 것으로 보였다. 4. 형태(形態) 및 이화학적(理化學的) 특성(特性)을 기준(基準)한 Taxonomy 분류(分類)에 의하면 Fine loamy, mixed, Acid, mesic, Sulfic Haplaquepts로 볼 수 있었고 해설적(解說的) 분류단위(分類單位)는 "Week Potential Acid Sulfate Soil" 이었다. 5. 암거배수(暗渠排水)와 석회시용(石灰施用) 및 용토(容土)처리는 표토의 황용탈(黃用脫)과 용수현상(湧水現狀) 억제로 개량 당년(當年)부터 정상적(正常的) 벼재배가 가능하였으나 개량(改良) 3년 후에는 pH가 다시 5.0이하로 되었다.