• Animal Bioscience
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• 제36권9호
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• pp.1453-1464
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• 2023

Objective: This study investigated the changes in bacterial communities within decomposing swine microcosms, comparing soil with or without intact microbial communities, and under aerobic and anaerobic conditions. Methods: The experimental microcosms consisted of four conditions: UA, unsterilized soil-aerobic condition; SA, sterilized soil-aerobic condition; UAn, unsterilized soil-anaerobic condition; and San, sterilized soil-anaerobic condition. The microcosms were prepared by mixing 112.5 g of soil and 37.5 g of ground carcass, which were then placed in sterile containers. The carcass-soil mixture was sampled at day 0, 5, 10, 30, and 60 of decomposition, and the bacterial communities that formed during carcass decomposition were assessed using Illumina MiSeq sequencing of the 16S rRNA gene. Results: A total of 1,687 amplicon sequence variants representing 22 phyla and 805 genera were identified in the microcosms. The Chao1 and Shannon diversity indices varied in between microcosms at each period (p<0.05). Metagenomic analysis showed variation in the taxa composition across the burial microcosms during decomposition, with Firmicutes being the dominant phylum, followed by Proteobacteria. At the genus level, Bacillus and Clostridium were the main genera within Firmicutes. Functional prediction revealed that the most abundant Kyoto encyclopedia of genes and genomes metabolic functions were carbohydrate and amino acid metabolisms. Conclusion: This study demonstrated a higher bacteria diversity in UA and UAn microcosms than in SA and SAn microcosms. In addition, the taxonomic composition of the microbial community also exhibited changes, highlighting the impact of soil sterilization and oxygen on carcass decomposition. Furthermore, this study provided insights into the microbial communities associated with decomposing swine carcasses in microcosm.

• Journal of Ginseng Research
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• 제4권1호
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• pp.104-120
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• 1980

The effects of temperature on transpiration, chlorophyll content, frequency and aperture of stomata, and leaf temperature of Panax ginseng were reviewed. Temperature changes of soil and air under spade roof were also reviewed. Growth responses of responses of ginseng plant at various temperature were assessed in relation to suseptibillity of ginseng plants. Reasonable management of ginseng fields was suggested based on the response of ginseng to various temperatures. Stomata frequency may be increased under high temperature during leaf$.$growing stage. Stomata aperture increased by high temperature but the increase of both frequency and aperture appears not enough for transpiration to overcome high temperature encountered during summer in most fields. Serial high temperature disorder, i.e high leaf temperature, chlorophyll loss, inhibition of photosynthesis, increased respiration and wilting might be alleviated by high humidity and abundant water supply to leaf. High air temperature which limits light transmission rate inside the shade roof, induces high soil temperature(optimum soil temperature 16∼18$^{\circ}C$) and both(especially the latter) are the principal factors to increase alternaria blight, anthracnose, early leaf fall, root rot and high missing rate of plant resulting in poor yield. High temperature disorder was lessen by abundant soil water(optimum 17∼21%) and could be decreased by lowering the content of availability of phosphorus and nitrogen in soil consequently resulting in less activity of microorganisms. Repeated plowing of fields during preparation seems to be effective for sterilization of pathogenic microoganisms by high soil temperature only on surface of soils. Low temperature damage appeared at thowing of soils and emergence stage of ginseng but reports were limited. Most limiting factor of yield appeared as physiological disorder and high pathogen activity due to high temperature during summer(about three months).

• Applied Biological Chemistry
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• 제26권4호
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• pp.248-254
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• 1983

토양(土壤) 살충제(殺蟲劑)인 thiolix를 토양(土壤) 수분(水分) 조건(條件)과 약제(藥劑)의 농도(濃度) 및 토양(土壤) 미생물(微生物)의 영향에 의한 경시적(經時的) 분해(分解) 양상과 토양(土壤) 효소(酵素)에 미치는 영향을 실험(實驗)한 결과를 요약(要約)하면 다음과 같다. 침수토양(浸水土壤) 조건(條件)에서는 반 토양(土壤) 조건(條件)보다, 밭 토양(土壤) 조건(條件)에서는 수분(水分)이 많을수록 분해(分解)가 촉진되었고 반 토양(土壤) 조건(條件)에서 저농도(低濃度)는 고농도(高濃度) 처리구(處理區)에서보다 분해율(分解律)이 증가(增加)하였다. 살균(殺菌)토양(土壤)이 비살균(非殺菌) 토양(土壤)에서 보다 분해(分解)가 완만했고 포도당 첨가는 분해를 촉진시켰다. TLC와 GLC에 의해 90일 처리시료(處理試料)에서 확인(確認)된 분해산물(分解産物)로는 Thiolix alcoho, Thiolix sulfate, Thiolix ether 등(等)이 있고 미확인(未確認) 물질(物質) 하나가 검출 되었다. 토양(土壤) 효소(酵素) acid phosphatase의 활성(活性)은 처리농도(處理濃度)가 높은 구에서, 수분함량(水分含量)이 낮은 구에서 활성(活性)이 더 저하되었으며 포도당 첨가시엔 더욱 증가하는 경향이었고, urease와 dehydrogenase의 활성(활성)은 처리농도((處理濃度)가 높을수록 더욱 저하되었다.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2001년도 추계 학술대회지
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• pp.34-58
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• 2001

Within the paper, an overview of organic farming in Europe countries is given and the Principle and skills of organic agriculture is shortly reported with special regard to Germany. The overview information on European organic farming is covered such as (1)development of organic farming, (2) organic farming organizations, (3)standards and certification, (4)implementation of EU council regulation, (5)state support, (6)implementation of Agenda 2000, (7)training and education, (8)advisory service and research situation. In the paper the principle and skills for organic farming which are practiced actually in the German organic farms is also reported. How to maintain and increase the fertility and microbiological activity of the soil by (1)cultivation of legumes, green manures or deep-rooting crops in multi-annual rotation system, (2)incorporation in the soil organic material, by-products from livestock farming is one of the major principle to organic crop production. Pest and diseases and weeds are controlled by any one, or a combination of the following measure; (1) choice of appropriate species and varieties, (2)appropriate rotation programs, (3)mechanical cultivation, (4)protection of natural enemies of pests through provision of favourable habitat and ecological buffer zone, (5)diversified ecosystems, (6)flame weeding, (7)natural enemies, (8)bio-dynamic preparations, (9)mulching and mowing, (10)grazing of animals, (11)mechanical controls, (12)steam sterilization.

• Journal of Ginseng Research
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• 제28권3호
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• pp.149-156
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• 2004

The objectives of this study were to investigate the morphology of mycorrhizal roots, and the effects of root age and soil texture on the mycorrhizal infection in ginseng (Panax ginseng C. A. Meyer) growing in Korea. Ginseng roots at ages of two to six years were collected from fields in late June. Their infection by arbuscular mycorrhizal fungi(AMF) was studied by clearing the roots and staining fungal hyphae with trypan blue. Root infection varied greatly depending on the developmental stages of young roots. Young tertiary roots, in diameter of smaller than 0.8 mrn, formed during the current growing season had root hairs and were frequently and in some cases heavily infected by AMF. Hyphal coils and arbuscules were abundant, while vesicles were rarely observed. Older secondary or tertiary roots in diameter of bigger than 1.0 mm with fully differentiated primary xylem formed during the previous growing season had no root hairs, and were not infected at all. The rates of mycorrhizal infection in the young tertiary roots were not affected by the age of the ginseng plants, suggesting that fungal populations might have not much changed during the aging of the cultivated fields up to six years. The differences in the infection rates among the different ages of ginseng were caused by differences in the amount of young tertiary roots in the samples. Soil texture, either sandy loam or clay loam, did not affect the rate of root infection. There were large variations in the infection rates among the different farms and locations within a farm. It strongly suggested that infection rates of the ginseng roots by AMF would be influenced by the practice of the farmers, possibly by avoiding consecutive planting, introduction of new topsoil, and the ways of handling the soil before transplanting the ginseng, such as fumigation or sterilization that might have affected indigenous inoculum sources of the AMF.

• 한국토양비료학회지
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• 제34권2호
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• pp.98-104
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• 2001

가. 우수 토양관리농가의 토성은 대부분 SiL이나 SL이었으며 점토함량은 7%~15%범위이었다. 토양의 용적밀도는 우수 토양관리농가 0.89, 인근농가 1.10이었고, 작토심은 평균 23.1cm로 인근농가 17.8cm 보다 깊었으며, 토양입단함량은 우수 토양관리 농가 61.6, 인근농가 54.2%이었다. 나. 토양의 화학성은 우수토양관리농가가 인근농가에 비해 pH, OM, $NO_3-N$가 양호한 편이었다. 다. 토양선충밀도는 우수 토양관리농가가 인근농가에 비해 뚜렷한 경향이 없었으나, 방선균의 밀도는 우수 토양관리 농가가 인근농가나 노지에 비하여 많은 편이었고, 토양병원성세균인 후사리움밀도는 두 농가를 제외하고는 우수토양관리농가가 인근에 비해 적었다. 라. 우수 토양관리농가의 공통특징은 정식전에는 담수+심경, 거친유기물을 시용하고 화학비료를 지양했으며, 정식 후에는 정적판수와 자가액비(+영양제)위주로 양수분을 공급하며, 휴한기에는 담수+태양열소독이나, 우기시 피복물제거, 옥수수 등 제염작물 재배 및 논으로의 환원 등이었다.

• 한국지하수토양환경학회지:지하수토양환경
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• 제19권6호
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• pp.49-58
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• 2014

This study was implemented as a part of the experiment to develop two kinds of soil-based Benzo[a]pyrene (BaP) proficiency testing materials (PTMs) for soil analysis. A test was carried out for the check of solubility of the reference material (high purity reagent) using several solvents. Another test was also conducted for the evaluation of homogeneity and stability of two kinds of candidate soil reference materials. The test analysis of BaP in terms of the candidate materials was conducted according to the Standard Soil Analytical Methods by Ministry of Environment. Dissolution of the reference material was shown to vary depending on solvent type and was higher in the order of Dichloromethane > Acetone > Acetone/MeOH (9 : 1) > N-hexane. In addition, the slope on calibration curve for BaP standard solutions was largest on BaP standard solutions prepared with dichloromethane of the tested solvents. Such tendency appeared egually in the commercial BaP standard solution. Therefore, it is thought to be reasonable to use dichloromethane as the solvent in case of the standard stock solution that is used for the measurement of BaP concentration in soil. ISO 13528 and IUPAC protocol were used for verification of homogeneity on the two kinds of soil candidate materials, Both candidate materials were sufficiently homogeneous. Stability assessment of the two candidate materials was made according to ISO Guide 35 and the result showed that both batches did not have any long-term and short term stability issues that might occur during shipping. However, monitoring results of BaP concentration in soil showed that BaP concentration of the two batches measured at 15 days after the sample preparation was reduced by about 24~37% compared with that of the samples measured on 0 day of the sample preparation. Identification was done with several treatments such as irradiation and sterilization etc. The major cause was shown to be irradiation to the samples.

• 한국약용작물학회:학술대회논문집
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• 한국약용작물학회 2011년도 춘계학술발표회
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• pp.168-169
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• 2011

• 농약과학회지
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• 제3권2호
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• pp.8-18
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• 1999

살균제 $^{14}C$-propiconazole의 토심별 분해를 멸균 및 비멸균 조건의 토양에서 조사하였다. Propiconazole을 토양에 7.55 mg/kg의 수준으로 처리한 후 배양기간 동안 발생된 $^{14}CO_{}2$ 양, 유기용매 추출 및 추출불가 잔류량, 그리고 분해산물을 등을 조사하였다. 배양기간 20주 동안 방출된 약제의 $^{14}CO_{2}$는 멸균 토양의 경우 토심에 따라 $0.7{\sim}1.3%$ 수준이었으며 비멸균 토양의 경우 $4.8{\sim}7.6%$이었다. 토양중 유기용매 추출불가 방사능은 멸균 토양의 경우 토심에 따라 $11.2{\sim}22.12%$ 수준이었으며 비멸균 토양의 경우 $22.1{\sim}41.9%$로서 비멸균 토양에서 더 높았다. 토양중 추출불가 잔류량은 주로 humin에 분포하였으며 배양시간에 따라 증가하였다. 토양중 propiconazole의 주요 분해산물은 수산화 치환된 형태 및 ketone성 화합물이었으며 멸균 토양에서는 모화합물만이 검출되었다. Propiconazole의 토양중 휘발성 물질 및 $CO_{2}$ 생성량과 잔류 및 분해특성은 이 화합물이 화학적 및 생물학적 분해에 안정함을 시사하였다.

• 농약과학회지
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• 제7권3호
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• pp.182-187
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• 2003

제초제 mefenacet의 토양 중 분해 특성을 알아 보고자 2 종의 토양을 비살균 토양을 대조로 하여 몇가지 조건으로 전처리한 다음 120일 동안 항온배양하면서 그 잔류량을 분석한 결과 약제처리 후 70일 경과시 대조토양은 $55\sim63%$가 분해 소실되었으나 살균토양에서는 $32\sim33%$, 담수토양에서는 $33\sim35%$가 소설 되어 mefenacet의 분해에 토양 미생물의 활성이 크게 영향을 끼치는 것으로 나타났다. 또한 mefenacet의 토양 중 분해에 미치는 수분함량의 영향을 조사한 결과 90 일간 배양 시 그 반감기는 포장 용수량의 20%와 50%에 해당하는 7.8%, 19.5%의 수분이 첨가된 토양에서는 각각 83과 82일 이었으며 80%인 31.2%의 수분이 첨가된 토양의 반감기가 61일로 단축되어 토양 수분 함량이 높을수록 mefenacet의 토양 중 분해 소실이 빠르게 일어남을 알 수 있었다. 결과적으로 mefenacet의 토양 중 분해 소실에는 토양 성분 중 유기물 함량과 토양 수분 함량이 중요한 인자로 작용하며 토양 미생물이 토양 성분과 더불어 mefenacet의 분해에 중요한 역할을 하고 있음을 시사하고 있다.