• 한국유기농업학회지
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• 제31권1호
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• pp.95-106
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• 2023

본 논문에서는 국내 산림 지역의 토양에서 서식하는 곤충병원성 진균을 insect-baiting 방법을 이용하여 분리하고자 하였으며, 곤충병원성 진균과 토양의 물리적, 화학적 특성과의 관계를 분석하고자 하였다. 국내 산림 지역 5곳을 선정하여 토양을 채집하였으며, 채집된 토양에서 총 42 분리주를 분리하였다. 그 중 Beauveria bassiana (42.9%)와 Metarhizium anisopliae (45.2%)가 주로 분리되었으며, 특히 M. anisopliae의 분포는 토양의 총 질소량(g/kg)과 유기물 함량(%)에 따라 달라지는 것이 확인되었다. 국내 산림 지역의 토양은 낮은 pH를 보였으며(pH 4-5), 전체 분리주 중에서 미사질 양토(silt loam)에서 50% 이상이 분리되었다. 본 연구의 결과는 통하여 토양의 물리적, 화학적 특성과 곤충병원성 진균의 분포 및 다양성과의 관계를 이해하는데 도움이 될 것으로 판단된다.

• 한국토양비료학회지
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• 제50권5호
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• pp.383-390
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• 2017

Heavy metal contamination of soil might be a cause of serious concern due to the potential health impacts of consuming contaminated products. In this study, the total content of heavy metals (Cd, Cr, Cu, Ni, Pb, Zn, As, and Hg) in soils was analyzed, and the difference of heavy metal contents depending on crops, soil characteristics, and topography was compared in 169 greenhouse soils obtained from Gyeongnam Province. The concentrations of the heavy metals were $0.25mg\;kg^{-1}$ (ranged 0.01~0.44) for Cd, $28.94(0.53{\sim}72.63)mg\;kg^{-1}$ for Cr, $26.03(0.5{\sim}166.13)mg\;kg^{-1}$ for Cu, $14.91(1.27{\sim}33.22)mg\;kg^{-1}$ for Ni, $15.76(0.43{\sim}57.1)mg\;kg^{-1}$ for Pb, $119.72(6.33{\sim}239.39)mg\;kg^{-1}$ for Zn, $2.54(0.01{\sim}23.57)mg\;kg^{-1}$ for As, and $0.049(0.012{\sim}0.253)mg\;kg^{-1}$ for Hg in topsoils. The concentrations of Pb and As in topsoil were highest in green pepper and those of Cd, Cr, and Ni were highest in melon. In addition, the concentrations of Cr and Ni were highest in diluvial terrace compared with the other topographies. Higher concentrations of Cd, Cr, and Ni were found in silty clay loam and silt loam soils than sandy loam and loam soils.

• 한국환경농학회지
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• 제40권3호
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• pp.231-238
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• 2021

BACKGROUND: Metal contamination of farmlands nearby abandoned mines is a serious environmental problem. This study was conducted to evaluate the efficiency of stabilizers on different type of the soils contaminated with metals. METHODS AND RESULTS: The texture of silt loam soil initially contaminated with heavy metal was artificially adjusted to loam and sandy loam by adding sand, and the soil organic matter content (1.5%) was also altered by adding peat to the soils at 3.5 and 8.0%. The soils were mixed with 3% (w/w) of each limestone, dolomite, and steel slag. For the soils with different textures, the bioavailability of As was found to be the lowest in sandy loam compared to others metals such as Cu, Pb, and Zn. The efficacy of limestone and dolomite was not significantly different compared to the soils having different organic matter contents, but the stabilization efficiency of steel slag increased as the soil organic matter content increased. Moreover, stabilizers showed inhibition effect on the uptake of metals to plant. CONCLUSION: The stabilizers were found as effective materials to immobilize metals in soil and to decrease plant uptake of metals. Studies are needed to deeply elucidate the interaction between influencing factors and various stabilizers.

• 한국균학회지
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• 제3권1호
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• pp.1-19
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• 1975

Since the importance of casing in fruit body formation of Agaricus bisporus has been emphasized, physico-chemical characteristics of casing materials were discussed by many workers and a mixture of peat and mineral soil as proper casing material has been adopted in many of mushroom growing countries. Because of limited resources of peat in Korea, it is necessary to find practical performance and substitutional materials for casing. The effect of casing on mycelial growth and mushroom yield of A. bisporus varied with materials, its combination and practices etc. The experiments to be discussed in this paper are concerned with pH and Ca of casing material which influence A bisporus, and changes of physico-chemical characteristics with mixing ratio of casing materials and its effect on A. bisporus. The optimum range of moisture content of each material, management of watering and application of physico-chemical characteristics casing materials was also investigated and re-use of weathered spent compost for casing material was described. 1. The effect of calcium on mycelial growth of A. bisporus at various pH in Halbschalentest showed different results with calcium sources. Best results were obtained around neutrality and fresh weight of fruit bodies grown in the range of pH 7 to 8 was highest among the tested levels. 2. Available moisture, pore space, organic matter, cation exchangeable capacity and exchangeable cation was increased by an increase of mixing ratio of peat in casing materials, while an adverse effect was obtained by addition of sand. 3. Mycelial growth on clay loam was more rapid at a lower bulk density of 0.75g/cc and at 20% moisture content on a dry weight basis at the same bulk density. 4. Mixing ratio of casing materials, 60 to 80 per cent by volume of peat mixed with 20 to 40 per cent of clay loam produced the highest yield of fresh fruit bodies and sand the lowest. However, per cent of open cap was highest in peat and lowest in sand. 5. Days required for fruit body initiation was shortened in mixtures of peat and clay loam by one to three days compared with other materials and the formation of flushes was clear. 6. The effect of some physico-chemical characteristics of casing materials on the fresh weight of fruit bodies were estimated by a multiple regression equation; Y=-923.86+$8.18X_1+8.04X_2+7.90X_3+0.12X_4+2.03X_5-0.82X_6-0.54X_7$ where $X_1,X_2,X_3,X_4,X_5,X_6,X_7$ are sand, silt, clay, available moistuer, porosity, organic matter and exchangeable cation respectively. The productivity of certain casing material could be predicted from this equation. 7. Fresh weight of fruit bodies was positively correlated with porosity exchangeable cation, organic matter, available moisture, silt and clay of materials; while sand was negatively correlated. On the contrary, sand was the unique factor reducing per cent of open cap. 8. Distribution of three phases of high productive casing material was concentrated in the range of 10 to 30 per cent solids, 15 to 30 per cent liquids, and 50 to 60 per cent in air volume. 9. Fresh weight of fruit bodies from peat was not affected with heavy watering but in clay loam and sandy loam severe crop losses occurred. Fresh weight of individual fruit was increased and open caps were decreased with heavy watering but light watering resulted in adverse effects: its effect was especially great in peat. 10. Optimum range of moisture content by weight on a dry basis was different with each casing material. To maintain optimum moisture content concerned with yield of fruit bodies and open cap, sandy loam and peat mixtures required daily watering of 0.6, 0.6 to 1. 2 and 1.2 to 2.4 liters per $3.3m^2$ of bed area, respectively. 11. Maximum yield of fruit body was recorded in the range of pF 2. 0 to 2. 5 of casing materials if organic matter content was below 4.2 per cent and in pF 1. 3 to 1.8 if above 7.1%. 12. pF curve of a certain casing material could be draws from moisture content at various pF values by multiple regression equations provided texture, organic matter and calcium of the casing material are given. Optimum moisture range of the casing materials also could be estimated by the equation. 13. It was possible to improve the phyico-chemical characteristics of clay loam and sandy loam by addition of weathered spent compost although the effect was less than in the case of peat. Fresh weight of fruit bodies wsa increased by addition of weathered spent compost but its effect was not as remarkable as peat. Accordingly, further studies will be required.

• 한국농공학회지
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• 제31권1호
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• pp.96-105
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• 1989

This laboratory study was performed to produce basic data for the estimation of water requirements for desalinization, through analyzing changes of the electrical conductivity and the exchangeable sodium percentage during the desalinization of reclaimed tidelands. Desalinization experiments were carried out by two water management practices, namely, the leaching method by subsurface drainage and the rinsing method by surface drainage, using samples of silt loam soil and silty clay loam soil collected in reclaimed tidelands. The results obtained from this study were summarized as follows : 1. The sample soils used in this study were saline-sodic soils with the high electrical conductivity and the high exchangeable sodium percentage. 2. Changes of the electrical conductivity and the exchangeable sodium percentage with water requirements for desalinization showed a similar tendency in the desalinization experiment by the same water management practice. 3. The regression equation between the relative electrical conductivity(EC/EC) and water requirements for desalinization(Dw/Ds) could be described by Dw/Ds=O. 29x(EC/EC.) -0.982 (Leaching method), Dw/Ds=3. 678X0. 030(EC/EC ) (Rinsing method). 4. The regression equation between the relative exchangeable sodium percentage (ESP/ESP ) and water requirements for desalinization (Dw/Ds) could be expressed in Dw/Ds = 0.039 x (ESP/ESP. ) - 1. 134 (Leaching method), Dw/Ds=7. 197X0. 024(ESP/ESP ) (Rinsing method). 5. It was estimated that water requirements for the adequate desalinization would be Dw/Ds=0.3 (Leaching method) and Dw/Ds=3.0 (Rinsing method)

• 한국농공학회지
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• 제30권4호
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• pp.127-133
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• 1988

This study was performed to obtain the basic data analyzing salt movement and desalinization effects, and two different desalinization experiments through leaching and rinsing were carried out, using samples of silt loam soil and silty clay loam soil collected in reclaimed tidelands. The relationships between the electrical conductivity of saturation extract and the electrical conductivity at various dilutions, and the correlations between electrical conductivity, total salt concentration, exchangeable sodium percentage and pH during the desalinization of reclaimed tidelands, were analyzed by the statistical method. The results obtained from this study were summarized as follows: 1.The sample soils used in this study were saline-sodic soils in accordance with the USDA classi- fication system of salt affected soils. 2.The electrical conductivity of saturation extract could be estimated conveniently, using the electrical conductivity of extract from various different soil-water suspensions. 3.The total salt concentration could be expressed in the electrical conductivity, but there was a little difference by soil textures. 4.The regression analysis showed that the relationship between the electrical conductivity of saturation extract and the exchangeable sodium percentage during the desalinization of reclaimed lands could be described by a linear regression equation. 5.The value of pH showed a tendency to increase according as the exchangeable sodium percentage decreased during the desalinization of reclaimed tidelands.

• 한국환경복원기술학회지
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• 제9권1호
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• pp.72-88
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• 2006

The optimal environmental ranges of the establishment phase for the distribution of Zizania latifolia and Typha angustifolia was determined to develop a set of basic data and criteria of planting substrate for the restoration, conservation and management of wetlands. The study was carried at 17 wetlands in the Kyunggi-do and Gyeongsangnam-do region where inland wetlands place intensively in June, 2005. Total 127 quadrats were sets in growing areas of Zizania latifolia and Typha angustifolia. $NO_3-N$, K, Ca, Mg and Na in the water variables and soil texture, LOI (loss on ignition), soil pH and soil conductivity in the soil variables were analyzed. The optimal range of water depth for the distribution of Zizania latifolia was -5~39cm, $NO_3-N$ content of water was <0.01~0.19ppm, K content of water was 0.1~5.9ppm, Ca content of water 0.5~44.9ppm, Mg content of water was 1.2~11.9ppm, Na content of water 3.4~29.9ppm, water conductivity was 48~450${\mu}S$/cm, respectively. The optimal range of LOI for the distribution of Zizania latifolia was 1.7~11.9%, soil conductivity was 25.5~149.9${\mu}S$/cm, respectively. The optimal range of water depth for the distribution of Typha angustifolia was -20~24cm, $NO_3-N$ content of water was <0.01~0.19ppm, K content of water was 0.2~2.9ppm, Ca content of water 0.6~19.9ppm, Mg content of water was 0.2~5.9ppm, Na content of water 3.5~19.9ppm, water conductivity was 96~450${\mu}S$/cm, respectively. The optimal range of LOI for the distribution of Typha angustifolia was 2.4~15.9%, soil conductivity was 17.6~149.9${\mu}S$/cm, respectively. The optimal soil texture were loam, silt loam and sandy loam in both species. The lower water depth (-20~40cm) is appropriate to increase biodiversity in both species dominated community and it is better to maintain water depth of 40~100cm for water purification. Both species appear frequently in the soil with high silt content.

• 한국환경농학회지
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• 제19권4호
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• pp.300-308
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• 2000

혐기적 토양조건하에서 제초제 $^{14}C-bifenox$의 분해를 조사하고자 하였다. $^{14}C-bifenox$를 미사질양토와 사양토에 각각 2.1 mg/kg 수준으로 처리한 후, 180일 동안 $25^{\circ}C$의 혐기적 조건하에서 배양하였다. 배양기간동안 bifenox의 무기화, 유기용매 추출성 및 추출불가 잔류량, 그리고 분해산물 등을 조사하였다. 배양기간 180일 동안 방출된 약제의 $^{14}CO_2$는 미사질양토와 사양토에서 각각 1.97%와 0.9% 수준이었다. 사양토에서의 추출불가 잔류량은 시험기간동안 표지된 $^{14}C$가 79.12%까지 눈에 띠게 증가하였고, 미사질양토에서 보다 그 양이 더 많았으며 이는 두 토양이 갖는 서로 다른 물리화학적 특성과 유기물 함량의 차이에서 기인된 것으로 판단되었다. 또한 추출불가 잔류량은 주로 humin에 분포하였으며 배양시간에 따라 증가하였다. 토양 중 bifenox의 주요 분해산물은 최종산물인 nitrofen, 5-(2,4-dichlorophenoxy)-2-nitrobenzoate 2,4-dichlorophenoxy aniline 그리고 methyl 5-(2,4-dichlorophenoxy) anthranilate으로 확인되었다. Bifenox의 토양 중 휘발성 물질 및 $CO_2$ 생성량과 잔류 및 분해독성은 이 화합물이 화학적 및 생물학적 분해에 안정함을 시사하였다.

• 한국약용작물학회지
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• 제7권4호
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• pp.282-287
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• 1999

본(本) 시험(試驗)은 1997년(年)부터 1998년(年)까지 2년간(年間) 사각 pot를 이용하여 식양토, 미사질양토, 사양토 등 3토성(土性)을 처리하여 년수별 생육과 수량 및 품질에 미치는 영향을 알고자 시험하였던 바 얻어진 결과를 요약하면 다음과 같다. 토성처리간 년수별 길경(桔硬) 경장의 경시적(輕視的) 변화를 보면 1년생(年生)은 7월(月) 10일(日)에서 8월(月) 10일(日) 사이, 2년생(年生)은 5월(月) 20일(日)에서 6월(月) 20일(日) 사이에서 최고로 성장 하였고 엽수, 분얼수, 분지수는 식양토가 양호하였으며, 사양토, 미사질양토 순(順)으로 많았다. 1년생(年生) 길경(桔硬)의 출현기 는 토양처리간 차이가 없었고 개화기는 식양토가 가장 빠르고 엽수 및 분얼수도 많았으며 주근장, 지근수, 주근경도 식양토가 사양토, 미사질양토보다 크고, 2년생(年生)도 같은 경향을 보였다. 건근수량(乾根收量)은 식양토에서 1년생(年生)은 274kg/10a, 2년생(年生)은 934kg/10a로 가장 많았고, 다음이 사양토. 미사질양토 순(順)이었고, 주근(主根) 표피색(表皮色)은 식양토는 담갈색, 사양토, 미사질양토 갈색이었으며, 주근육색(主根肉色)은 식양토가 황백색이였다. 길경(桔硬) 1년색(年生), 2년생(年生)의 엑스 함량은 사양토가 1년생(年生) 47. 1%, 2년생(年生)은 36.3%로서 가장 높았고, 다음이 미사질양토, 식양토 순(順)이었으며, 반면에 조(粗)사포닌 함량은 식양토가 1년생(年生)은 3.0%, 2년생(年生)은 3.6%로서 많은 편이었으나 토양 처리간 유의성은 인정되지 않았다.

• 한국토양비료학회지
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• 제27권1호
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• pp.33-39
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• 1994

시설원예지(施設園藝地) 토양(土壤)의 염농도(鹽濃度) 및 화학성분(化學成分)의 조성(組成)에 영향(影響)을 주는 요인(要因)을 밝히기 위하여 중북부지역(中北部地域)(양주, 고양, 화성, 평택, 수원)의 40개(個) 농가(農家)를 대상(對象)으로 하우스의 내부(內部)와 외부토양(外部土壤)을 표토(表土)(0~15cm)와 심토(深土)(15~30cm)별(別)로 채취(採取)하여 입경분석(粒徑分析) 및 화학분석(化學分析)을 실시하고 이 결과(結果)를 각(各) 요인별(要因別)로 검토(檢討)하여 얻어진 내용(內容)을 요약(要約)하면 다음과 같다. 1. 시설원예지(施設園藝地) 토양(土壤)의 화학적(化學的) 성질(性質)은 포토(表土)에서 평균치(平均値)로 pH 5.8, EC $3.59mScm^{-1}$, O.M 4.2%, 유효태 $P_2O_5$ 1,178 ppm, $NO_3-N$ 180 ppm, 유효태 $SO_4{^{2-}}$ 353 ppm, $Cl^-$ 240 ppm, 치환성 Na 0.40me/100g이었다. 2. 하우스 내부(內部) 토양(土壤)은 표토(表土)에 있어 하우스 외부토양(外部土壤)에 비(比)하여 질산태(窒酸態) 질소(窒素), 유효(有效) 황(黃), 염소(鹽素)의 함량(含量)은 2.5~3배, 치환성(置換性) 염기함량(鹽基含量)은 1.2~1.8배, EC는 2.8배 높았고 pH는 0.3 낮았다. 이 경향(傾向)은 심토(深土)에서도 같았다. 3. 토성(土性)의 분포비율(分布比率)은 사양토(砂壤土) 32.5%, 양토(壤土) 37.5%, 미사질양토(微砂質壤土) 30.0%이었고 염농도(鹽濃度), 질산태(窒酸態) 및 암모니아태(態) 질소(窒素)와 유효(有效) 황(黃)의 함량(含量)은 세입질(細粒質)인 미사질양토(微砂質壤土)에서 높았고, 유효인산(有效燐酸)의 함량(含量)과 pH값은 사양토(砂壤土) 쪽에서 높았다. 4. 유기물(有機物)과 유효인산(有效燐酸)의 함량(含量)은 경작년수(耕作年數)가 오래된 토양(土壤)일수록 높았으나 염농도(鹽濃度)를 비롯하여 질산태질소(窒酸態窒素), 유효(有效) 황(黃), 염소(鹽素) 및 치환성(置換性) Mg와 Na의 함량(含量)은 경작년수(耕作年數)가 2~4년(年) 토양(土壤)이 5년(年) 이상(以上)된 토양(土壤)보다 더 높았다. 5. 다중회귀(多衆回歸) 분석(分析) 결과(結果) 염농도(鹽濃度)에 미치는 기여도(寄與度)는 $NO_3-N$ > 유효태 $SO_4{^{2-}}$ > 치환성 Na > $Cl^-$ > 유효태 $P_2O_5$ > $NH_4-N$ > 치환성 Mg, 치환성 Ca의 순(順)으로 음(陰)이온이 우세(優勢)하게 작용(作用)하였다. 6. 염농도(鹽濃度) EC에 대한 총 음(陰)이온 함량(含量)(${\sum}A$)과 총 양(陽)이온 함량(含量)(${\sum}C$)과의 상관계수(相關係數)는 각각 $r=0.932^{**}$, $r=0.452^{**}$로 나타났다.