• Title/Summary/Keyword: Soil water potential

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Prevalence of Pathogenic Bacteria in Livestock Manure Compost and Organic Fertilizer (가축분퇴비와 유기질비료에서 병원성박테리아의 분포도 분석)

  • Jung, Kyu-Seok;Heu, Sung-Gi;Roh, Eun-Jung;Lee, Dong-Hwan;Yun, Jong-Chul;Kim, Kye-Hoon
    • Korean Journal of Soil Science and Fertilizer
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    • v.44 no.5
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    • pp.824-829
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    • 2011
  • In recent years, there has been an increasing public concern about fecal contamination of water, air and agricultural produce by pathogens residing in organic fertilizers such as manure, compost and agricultural by-products. Efforts are now being made to control or eliminate the pathogen populations at on-farm level. Development of efficient on-farm strategies to mitigate the potential risk posed by the pathogens requires data about how the pathogens prevail in livestock manure composts and organic fertilizers. Microbiological analysis of livestock manure composts and organic fertilizers obtained from 32 and 28 companies, respectively, were conducted to determine the total aerobic bacteria count, coliforms, Escherichia coli count and the prevalence of Staphylococcus aureus, Bacillus cereus, Salmonella spp., Escherichia coli O157:H7, Listeria monocytogenes, and Cronobacter sakazakii. The total aerobic bacteria counts in the livestock manure composts and organic fertilizers were in the range of 7 to $9log\;CFU\;g^{-1}$ and 4 to $6log\;CFU\;g^{-1}$, respectively. In the livestock manure composts, coliforms and E. coli were detected in samples obtained from 4 and 2 companies, respectively, in the range of 2 to $5log\;CFU\;g^{-1}$ and $2log\;CFU\;g^{-1}$. In the organic fertilizers, coliforms and E. coli were detected in samples obtained from 4 and 1 companies, respectively, in the range of 1 to $3log\;CFU\;g^{-1}$ and $2log\;CFU\;g^{-1}$. In 3 out 32 compost samples, B. cereus was detected, while other pathogens were not detected. In 28 organic fertilizers, no pathogens were detected. The complete composting process can result in the elimination of pathogens in livestock manure compost and organic fertilizer. The results of this study could help to formulate microbiological guidelines for the use of compost in environmental-friendly agriculture. This research provides information regarding microbiological quality of livestock manure compost and organic fertilizer.

Changes of Microbial Activity and Physicochemical Environment during Composting of Papermill Sludge in a Pilot Plant (제지슬럿지의 퇴비화 과정 중 미생물활성 및 이화학적 환경변화)

  • Chung, Young-Ryun;Chung, Man-Hoon;Han, Shin-Ho;Oh, Say-Kyun
    • Journal of the Korea Organic Resources Recycling Association
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    • v.3 no.2
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    • pp.79-89
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    • 1995
  • Changes of microbial activity and physicochemical environment during composting of papermill sludge(PMS) in the pilot plant equipped with an agitated bed reactor were monitored for establishing the efficient composting system. Microbial activity determined as the evolution of $CO_2$ increased for the first 10 days after introduction of PMS to the reactor and decreased thereafter. Population changes of microorganisms in the reactor-PMS were not typical as in windrow system. The ratio of thermophilic bacteria to mesophilic bacteria, however, increased slowly even 23 days after introduction. Temperature of PMS increased rapidly from the first day and reached $62^{\circ}C$ at 7 days after introduction and decreased slowly thereafter. The acidity of PMS was pH 6.8 initially, increased to pH 8.0 after 7 days and decreased to pH 7.4 after 23 days. Redox potential(Eh) of PMS was -320mV at the beginning of composting, but it was increased with time to reach -15mV after 23 days composting. However, Eh of PMS pre-sterilized before measurement was average 50mV, regardless of composting periods indicating the major role of microorganisms during composting process. Water content of PMS was 67% initially and decreased to about 50% after 23 days composting in the reactor. Less than 13 days-old compost inhibited growth of radish in the container mixture with bed soil. Based on statistical analysis of microbial and physicochemical parameters of PMS during composting, an equation was developed for determining compost maturity. A number of experiments using various organic wastes are required before application of the formular to the practical use.

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Assessment of Groundwater Contamination Using Geographic Information System (지리정보시스템을 이용한 지하수 오염 평가)

  • 전효택;안홍일
    • Journal of the Korean Society of Groundwater Environment
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    • v.5 no.3
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    • pp.129-140
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    • 1998
  • In this study two sites were selected to investigate groundwater contamination and spatial relationship between pollution level and its source. One is the Asan area, agricultural district where pollution sources are scattered. The other is the Gurogu area of Seoul city, industrial district where industrial complex and residential areas are located. Groundwater samples collected from these districts were analysis for chemical constituents. The attribute value files of the chemical constituents of groundwater and the spatial layers have been constructed and the pollution properties have been investigated to find out spatial relationships between the groundwater constituents and pollution sources using CIS. Relatively high contents of Si and HCO$_3$ in groundwater from the Asan area reflect the effect of water-rock interaction, whereas high contents of Cl, NO$_3$, SO$_4$and Ca in groundwater from the Gurogu area are due to the pollution of various sources. Pollution over the critical level of Korean Dinking Water Standard has been investigated from 15 sampling sites out of 40 in the Asan area, and 33 sampling sites out of 51 in the Gurogu area. There is pollution of NO$_3$, Cl, Fe, Mn, SO$_4$and Zn in groundwater from the Gurogu area, and that of NO$_3$, SO$_4$and Zn in groundwater from the Asan area. Principal pollution in both areas is NO$_3$contamination. Deep groundwater from the Asan area is not contaminated with NO$_3$except for one site and most of shallow groundwater near the potential point sources such as factory and stock farm is contaminated seriously. Groundwater from the Gurogu area has been already polluted seriously considering the fact of contamination of deep groundwater. This study reports a spatial relationship between the pollution level and pollution source using GIS.

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Effects of Small Scale Post-Harvest Facility and Hygiene Education on the Level of Microbial Safety in Korean Leeks Production (영양부추 생산농가의 소규모 수확후 처리시설 적용과 위생교육에 따른 미생물학적 안전성 향상 효과)

  • Kim, Se-Ri;Kim, Jin-Bae;Lee, Hyo-Sup;Lee, Eun-Sun;Kim, Won-Il;Ryu, Song-Hee;Ha, Jihyung;Kim, Hwang-Yong;Ryu, Jae-Gee
    • Journal of Food Hygiene and Safety
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    • v.30 no.3
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    • pp.249-257
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    • 2015
  • The purposes of this study were to develop a small scale post-harvest facility, and consequently to evaluate the effects of applying the facility along with hygiene education on the level of microbial safety in Korean leeks production. A total of 135 samples were collected at three Korean leeks farms in Yangju, Gyeonggi province. Food safety indicators (Aerobic plate count (APC), coliform count, and Escherichia coli) and foodborne pathogens (E. coli O157:H7, Salmonella spp., Staphylococcus aureus, Listeria monocytogenes, and Bacillus cereus) on/in the samples were assessed. The microbial load measured as APC with harvesting tools such as comb, chopping board, and knife, at the farms where the small scale post-harvest facility had been operated (Farms A and B) was lower than that at another farm having no post-harvest facility (Farm C) by 1.44~2.33 log CFU / $100cm^2$. Moreover, the chopping board from Farm C was observed being contaminated with B. cereus at 6.03 log CFU / $100cm^2$. The coliform counts from the samples increased by 0.57~1.89 log CFU/g after leeks was submerged in ground water for washing. E. coli was recovered from leeks, soil, and the ground water used in the washing process, while no E. coli O157:H7, Salmonella spp., and L. monocytogenes was detected. Our results indicated that the small scale post-harvest facility developed in this study as well as the hygiene education played an important role in enhancing the level of microbial food safety in the leeks production environment. However, a disinfection technique could be needed during the washing step in order to prevent a potential contamination.

Geochemical Characteristics and Pollution Level of Heavy Metals of Asian Dust in Daejeon Area, 2007 (spring season) (2007년 봄철 대전지역에서 발생한 황사 및 대기부유물의 지구화학적 특성 및 중 금속의 오염도)

  • Lee, Pyeong-Koo;Youm, Seung-Jun;Bae, Beob-Geun
    • Economic and Environmental Geology
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    • v.45 no.3
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    • pp.217-235
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    • 2012
  • We evaluated the geochemical characteristics and their potential pollution of Asian Dusts in Daejeon, Korea during spring 2007. Compared with the chemical compositions of soils in source area of Asian Dust, those of aerosols in Daejeon were enriched with trace elements (ten to hundred fold), inferring that pollutants from China have affected on local environment in adjoining country such as Korea. Chemical analysis of aerosols during Asian dust showed that fine particles ($PM_{2.5}$) contained high contents of trace elements such as Cr, Cu, Pb, Zn, V, S, As, Cd, Co, Ni, Mo, Sb, Cs, Rb, Th, Sc and Y. In the case of TSP (Total Suspended Particle), Zr, Sr, Ba, Li, Th and U were contained much more than other trace elements. The contents of some elements (i.e. Li, Cs, Co, U, Cr, Ni, Rb, V, Th, Y, Sr and Sc) in aerosols collected in Asian Dust period, which are not likely enriched by air pollutants, were higher (2 - 4.2 fold) than those in Non Asian Dust period, indicating that these elements could be used as indicator elements for determining the occurrence of Asian Dust phenomena (especially, Sr, V, Cr & Li). In the case of Asian Dust coming through the big cities and/or industrial areas of China, the domestic aerosols had higher contents of trace elements (such as S, Cd, Zn, Pb, Cu, Mo and As) than those from Northeastern China via North Korea, indicating that the transportation courses of air mass are very important to determine the pollution degrees. Using the enrichment factors of trace elements in aerosols during Asian Dust and Non Asian Dust, we identified that some elements (i.e. S, Zn, Cu, Pb, As, Mo and Cd) were most problematic in terms of environmental hazard aspects, and these elements could affect adverse effects on human health as well as ecosystem and surface environment (soil and water) through long-lived precipitation.

A Study on the Development of Experiential Nature Education Program in the Urban Forest Park - A Case Study of Yeongheung Park in Suwon - (도시 산림공원의 체험형 자연교육 프로그램 개발 연구 - 수원 영흥공원을 대상으로 -)

  • Chang, Ye-Na;Kim, Sung-Hee;Han, Bong-Ho;Choi, Jin-Woo
    • Journal of the Korean Institute of Landscape Architecture
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    • v.47 no.6
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    • pp.12-23
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    • 2019
  • The purpose of this study was to develop and study an experiential natural education program that could emphasize the importance of the natural environment by providing natural experience opportunities using the natural resources of the urban forest parks using Youngheung Park in Suwon, Gyeonggi Province as a target site. The research target was limited to Suwon Yeongheung Park, which had the potential to become a place for education, where urban forest conservation and sustainable use already coexist. The natural education resources derived by surveying and analyzing the basic environment and the ecology of plants and animals in Suwon Yeongheung Park were organized to establish program goals, directions, and themes. Suwon Yeongheung Park is a water-rich forest that forms an ecological system of wetlands, including rice paddies, muknon wetlands, and dungbun, near a valley area. The U-shaped walkway was smoothly formed along the ridge and includes Doran-gil, which is among the Palochrome Road, designated by the city of Suwon. The soil is acidic, with a pH 4.40, due to urban pollution and acid rain, and is not good for plant growth. Most of the artificial forests, natural forests, and arable land were found using land use and extant life surveys. Old trees were distributed in artificial forests, the oak clusters in natural forests, and the fields and darrinones were distributed in the arable areas. As the forest vegetation declined, the cedar forest was underway, and the cedar trees and red bean pear trees were cultivated due to their adaptability to the urban environment. There are 13 large of 180 sacks, one being 109 centimeters in diameter, the largest silvery tree, and 105 oak trees, provide food and shelter for animals. Six species of waterfowl that used the 22 kinds of forest wetlands, while four species of amphibians and two species of reptiles reside in the wetlands. Natural Monument No. 327, Mauryuk, Class II Endangered Wildlife, was also observed in the wetlands. Eight other species of surface dragonflies and three species of butterflies were observed. By systemizing the resources, members, and characteristics of the forest ecosystems in Suwon Yeongheung Park based on five criteria, the program for a hands-on natural education was presented with the aim of understanding the urban forest ecosystem in Suwon Yeongheung Park, having an affinity with the city, and recognizing its relationship with the community and society. However, further research is needed as there are limitations of research on programs characterized by different ages and classes.

Characteristics of Natural Arsenic Contamination in Groundwater and Its Occurrences (자연적 지하수 비소오염의 국내외 산출특성)

  • Ahn Joo Sung;Ko Kyung-Seok;Lee Jin-Soo;Kim Ju-Yong
    • Economic and Environmental Geology
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    • v.38 no.5 s.174
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    • pp.547-561
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    • 2005
  • General characteristics of groundwater contamination by As were reviewed with several recent researches, and its occurrence in groundwater of Korea was investigated based on a ffw previous studies and a groundwater quality survey in Nonsan and Geumsan areas. In Bangladesh, which has been known as the most serious arsenic calamity country, about $28\%$ of the shallow groundwaters exceeded the Bangladesh drinking water standard, $50{\mu}g/L$, and it was estimated that about 28 million people were exposed to concentrations greater than the standard. Groundwater was characterized by circum-neutral pH with a moderate to strong reducing conditions. Low concentrations of $SO_4^{2-}$ and $NO_3^-$, and high contents of dissolved organic carbon (DOC) and $NH_4^+$ were typical chemical characteristics. Total As concentrations were enriched in the Holocene alluvial aquifers with a dominance of As(III) species. It was generally agreed that reductive dissolution of Fe oxyhydroxides was the main mechanism for the release of As into groundwater coupling with the presence of organic matters and microbial activities as principal factors. A new model has also been suggested to explain how arsenic can naturally contaminate groundwaters far from the ultimate source with transport of As by active tectonic uplift and glaciatiion during Pleistocene, chemical weathering and deposition, and microbial reaction processes. In Korea, it has not been reported to be so serious As contamination, and from the national groundwater quality monitoring survey, only about $1\%$ of grounwaters have concentrations higher than $10{\mu}g/:L.$ However, it was revealed that $19.3\%$ of mineral waters, and $7\%$ of tube-well waters from Nonsan and Geumsan areas contained As concentrations above $10{\mu}g/:L.$. Also, percentages exceeding this value during detailed groundwater quality surveys were $36\%\;and\;22\%$ from Jeonnam and Ulsan areas, respectively, indicating As enrichment possibly by geological factors and local mineralization. Further systematic researches need to proceed in areas potential to As contamination such as mineralized, metasedimentary rock-based, alluvial, and acid sulfate soil areas. Prior to that, it is required to understand various geochemical and microbial processes, and groundwater flow characteristics affecting the behavior of As.

How to Reflect Sustainable Development, exemplified by the Equator Principles, in Overseas Investment (해외투자(海外投資)와 지속가능발전 원칙 - 프로젝트 파이낸스의 적도원칙(赤道原則)을 중심으로 -)

  • Park, Whon-Il
    • THE INTERNATIONAL COMMERCE & LAW REVIEW
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    • v.31
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    • pp.27-56
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    • 2006
  • Today's financial institutions usually take environmental issues seriously into consideration as they could not evade lender liability in an increasing number of cases. On the international scene, a brand-new concept of the "Equator Principles" in the New Millenium has driven more and more international banks to adopt these Principles in project financing. Sustainable development has been a key word in understanding new trends of the governments, financial institutions, corporations and civic groups in the 21st century. The Equator Principles are a set of voluntary environmental and social guidelines for sustainable finance. These Principles commit bank officers to avoid financial support to projects that fail to meet these guidelines. The Principles were conceived in 2002 on an initiative of the International Finance Corporation(IFC), and launched in June 2003. Since then, dozens of major banks, accounting for up to 80 percent of project loan market, have adopted the Principles. Accordingly, the Principles have become the de facto standard for all banks and investors on how to deal with potential social and environmental issues of projects to be financed. Compliance with the Equator Principles facilitates for endorsing banks to participate in the syndicated loan and help them to manage the risks associated with large-scale projects. The Equator Principles call for financial institutions to provide loans to projects under the following circumstances: - The risk of the project is categorized in accordance with internal guidelines based upon the environmental and social screening criteria of the IFC. - For Category A and B projects, borrowers or sponsors are required to conduct a Social and Environmental Assessment, the preparation of which must meet certain requirements and satisfactorily address key social and environmental issues. - The Social and Environmental Assessment report should address baseline social and environmental conditions, requirements under host country laws and regulations, sustainable development, and, as appropriate, IFC's Environmental, Health and Safety Guidelines, etc. - Based on the Social and Environmental Assessment, Equator banks then make agreements with borrowers on how they mitigate, monitor and manage the risks through a Social and Environmental Management System. Compliance with the plan is included in the covenant clause of loan agreements. If the borrower doesn't comply with the agreed terms, the bank will take corrective actions. The Equator Principles are not a mere declaration of cautious banks but a full commitment of lenders. A violation of the Principles in the process of project financing, which led to an unexpected damage to the affected community, would not give rise to any specific legal remedies other than ordinary lawsuits. So it is more effective for banks to ensure consistent implementation of the Principles and to have them take responsible measures to solve social and environmental issues. Public interests have recently mounted up with respect to environmental issues on the occasion of the Supreme Court's decision (2006Du330) on the fiercely debated reclamation project at Saemangeum. The majority Justices said that the expected environmental damages like probable pollution of water and soil were not believed so serious and that the Administration should continue to implement the project seeking ways to make it more environment friendly. In this case, though the Category A Saemangeum Project was carried out by a government agency, the Supreme Court behaved itself as a signal giver to approve or stop the environment-related project like an Equator bank in project financing. At present, there is no Equator bank in Korea in contrast to three big banks in Japan. Also Korean contractors, which are aggressively bidding for Category A-type projects in South East Asia and Mideast, might find themselves in a disadvantageous position because they are generally ignorant of the environmental assessment associated with project financing. In this regard, Korean banks and overseas project contractors should care for the revised Equator Principles and the latest developments in project financing more seriously. It's because its scope has expanded to the capital cost of US$10 million or more across all industry sectors regardless of developing countries or not. It should be noted that, for a Korean bank, being an Equator bank is more or less burdensome in a short-term period, but it must be conducive to minimizing risks and building up good reputation in the long run.

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Acid Drainage and Damage Reduction Strategy in Construction Site: An Introduction (건설현장 산성배수의 발생현황 및 피해저감대책)

  • Kim, Jae-Gon
    • Economic and Environmental Geology
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    • v.40 no.5
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    • pp.651-660
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    • 2007
  • Acid drainage has been recognized as an environmental concern in abandoned mine sites for long time. Recently, the environmental and structural damage by acid drainage is a current issue in construction sites in Korea. Here, the author introduces the type of damages by acid drainage in construction sites and emphasizes the importance of geoscience discipline in solving the problem. Metasedimentary rock of Okcheon group, coal bed of Pyeongan group, Mesozoic volcanic rock. and Tertiary sedimentary and volcanic rocks are the major rock types with a high potential for acid drainage upon excavation in Korea. The acid drainage causes the acidification and heavy metal contamination of soil, surface water and groundwater, the reduction of slope stability, the corrosion of slope structure, the damage on plant growth, the damage on landscape and the deterioration of concrete and asphalt pavement. The countermeasure for acid drainage is the treatment of acid drainage and the prevention of acid drainage. The treatment of acid drainage can be classified into active and passive treatments depending on the degree of natural process in the treatment. Removal of oxidants, reduction of oxidant generation and encapsulation of sulfide are employed for the prevention of acid drainage generation.

Characterization of Streptomyces netropsis Showing a Nematicidal Activity against Meloidogyne incognita (Meloidogyne incognita에 살선충활성을 보이는 신규 Streptomyces netropsis의 살선충 특성 규명)

  • Jang, Ja Yeong;Choi, Yong Ho;Joo, Yoon-Jung;Kim, Hun;Choi, Gyung Ja;Jang, Kyoung Soo;Kim, Chang-Jin;Cha, Byeongjin;Park, Hae Woong;Kim, Jin-Cheol
    • Research in Plant Disease
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    • v.21 no.2
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    • pp.50-57
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    • 2015
  • Control of nematode has become difficult owing to the restricted use of effective soil fumigant, methyl bromide, and other non-fumigant nematicides. Therefore, it is urgently necessary to develop microbial nematicide to replace chemical nematicides. In this study, the 50% aqueous methanol extraction solution of fermentation broths of 2,700 actinomycete strains were tested for their nematicidal activity against second stage of juveniles (J2s) of Meloidogyne incognita. As the results, only the 50% aqueous methanol extraction solution of AN110065, at 20% equivalent to 10% fermentation broth, showed strong nematicidal activity with 78.9% of mortality 24 h after treatment and 94.1% of mortality at 72 h. The 16S rRNA gene sequencing showed that the strain sequence was 99.78% identical to Streptomyces netropsis. The extract of S. netropsis AN110065 fermentation broth was successively partitioned with ethyl acetate and butanol and then the ethyl acetate, butanol and water layers were investigated for their nematicidal activity against the M. incognita. At $1000{\mu}g/ml$, ethyl acetate layer showed the strongest activity of 83.5% of juvenile mortality 72 h after treatment. The pot experiment using the fermentation broth of AN110065 on tomato plant against M. incognita displayed that it evidently suppressed gall formation at a 10-fold diluent treatment. The tomato plants treated with the fermentation broth of S. netropsis AN110065 did not show any phytotoxicity. The results suggest that S. netropsis AN110065 has a potential to serve as microbial nematicide in organic agriculture.