• Title/Summary/Keyword: organic index

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Effect of Foulant Characteristics on Membrane Fouling Index (오염물질의 특성이 막오염 지수에 미치는 영향)

  • Park, Chanhyuk;Kim, Hana;Hong, Seungkwan
    • Journal of Korean Society of Water and Wastewater
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    • v.19 no.6
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    • pp.775-780
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    • 2005
  • This study was performed to investigate the effect of foulant characteristics on Membrane fouling index such as Silt Density Index (SDI) and Modified Fouling Index (MFI). A linear relationship was found relating the fouling index (both SDI and MFI) on particle concentration, but fouling index values were nonlinearly (exponentially) with increasing organic concentration. When organic matter was the primary cause of fouling, the MFI was not accurately predicted due to internal fouling such as pore adsorption. The fouling index was determined mainly by particle characteristics when both particle and organic coexisted in the feed water. This observation was attributed to lessening of organic pore adsorption by particle cake layer formed on the membrane surface. Bench-scale actual fouling experiments demonstrated that permeate flux declines much faster with feed water containing particles than organic matters although fouling potential predicted by SDI values were identical, indicating that the accurate prediction of fouling potential requires the development of fouling index reflecting different foulant characteristics.

Insect Diversity in Non-organic and Organic Chinese Cabbage and Pepper Farms (유기 재배 및 관행 재배 배추와 고추밭의 곤충상 조사)

  • Jin, Joon-Ho;Cho, Sae-Youll
    • The Korean Journal of Pesticide Science
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    • v.14 no.3
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    • pp.255-260
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    • 2010
  • Insect diversities in non-organic and organic Chinese cabbage and pepper fields were studied in 2009. Sixty-two species in 9 orders and 24 species in 6 orders were collected in organic and non-organic Chinese cabbage fields, respectively. In pepper fields, insect diversity was also higher in organic fields than in non-organic ones. Dominance index, diversity index, richness index, and evenness index in organic fields were higher than those in non-organic fields.

Latitudinal Differences in the Accumulation of Soil Organic Matter in Selected Kroean Forest Types (한반도의 몇 삼림형에 따른 임토육기물 축종량의 위도적차이에 대해서)

  • 임양재
    • Journal of Plant Biology
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    • v.14 no.1
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    • pp.5-13
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    • 1971
  • Accumulation of soil organic matter and its vertical distribution at different latitudes in peninsular Korea were studied in the soil of four different forest types viz. Pinus densiflora forest, Castanea forest, Quercus acutissima forest and Carpinus laxiflora forest. Among them, accumulation of soil organic matter in Cheju sites, with a mean annual temperature of 15$^{\circ}C$, was maximum with increasing latitude, soil organic matter concentration decreased. Considering the relationship between concentration of soil organic matter and some climatic conditiions, it seems that concentrations of soil organic matter is a function of annual temperature, especially warmth index or cold index.

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Verification of Silt Density Index (SDI) as a fouling index for reverse osmosis (RO) feed water (역삼투 공정 파울링 지표로서 SDI(Silt Density Index)의 적합성 검증)

  • Kim, Su-Han;Kim, Chung-H.;Kang, Suk-H.;Lee, Won-T.;Lim, Jae-L.
    • Journal of Korean Society of Water and Wastewater
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    • v.25 no.4
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    • pp.489-495
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    • 2011
  • Silt Density Index (SDI) has been used as a fouling index for reverse osmosis (RO) processes for decades. In order to decrease RO fouling, feed water should meet SDI standard, which was used to select a proper pretreatment system for RO processes. However, SDI is supposed to be sensitive only to particles larger than 0.45 ${\mu}m$ in terms of diameters while nanoparticles and dissolved organic matter can be potent foulants for RO processes. Our study started from the suspected performance of SDI as a RO fouling index. SDI data from pilot plants located world wide including South Korea were collected and analyzed. Suspended partcle concentration (i.e., turbidity and particle counts), and dissolved organic matter concentration (i.e., dissolved orgnaic carbon (DOC) concentration) data were also collected and compared to SDI values of same water samples. We found that SDI values were not only affected by suspended particle concentration but also by dissolved organic matter concentration. Therefore SDI can be used as a reasonable fouling index for RO feed water because the main foulants for RO processes are suspended particle and dissolved organic matter.

Selection of the Optimum Organic Matter Index for Surface Water Quality Management (지표수 수질관리를 위한 적정 유기물질지표 선정)

  • Han, Dae Ho;Choi, Ji-Yong
    • Journal of Environmental Policy
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    • v.10 no.4
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    • pp.61-80
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    • 2011
  • Through concentrated investments in environmental regulations centered around BOD, which is a biodegradable matter index, and basic environmental infrastructures, national BOD pollution level has continuously improved. Nonetheless, limitations of BOD management system has become evident through nation-wide stagnation and/or increases of refractory organic matters, such as COD, at main drinking water sources, and the need for a new index, which can easily indicate different environmental conditions, has increased. Therefore, this study suggests a new organic management index for a proper management of surface water. $COD_{Cr}$ and TOC were examined as candidates for surface water quality management index, and it was found that TOC was more appropriate than $COD_{Cr}$ as an organic matter management index. Through this study, it was found that TOC possesses following qualities: a more representative index; international acceptability; monitoring program is easier; better availability of analysis techniques; better accuracy and precision of analysis; less time required for analysis; ease of operation; management of disinfection byproducts; connection with present policies; existence of foreign and domestic application case studies; and correlation with water ecosystem.

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Distribution Characteristics of Organic Carbon and Nutrient in Effluent of Land-based Aquaculture Farms around Wando in Korea (하계 완도 주변 육상 양식장 배출수 중 유기탄소 및 영양염의 분포 특성)

  • GyuRi Kim;Yujeong Choi;Tae–Hoon Kim
    • Ocean and Polar Research
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    • v.45 no.3
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    • pp.103-111
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    • 2023
  • To evaluate the impact of effluents from land-based fish farms on the coastal ocean of Wando, Korea, we analyzed inorganic nutrients, particulate organic carbon (POC), dissolved organic carbon (DOC), and colored dissolved organic matter (CDOM) in the effluent and influent of land-based fish farms during the summer (July) of 2021. The average concentrations of nutrients (Dissolved inorganic nitrogen, phosphorus, and silicate; DIN, DIP, and DSi, respectively) in the effluents of this study area were 17±3.7 μM, 1.4±0.7 μM, and 14±1.6 μM, respectively. The average concentrations of POC and DOC were 37±22 μM and 81±13 μM, respectively, with POC accounting for about 30% for total organic carbon in effluents. The Reduced Dissolved Inorganic Nitrogen/Total Dissolved Inorganic Nitrogen ratio (0.7), potential short-period index, indicates that the discharge of nutrients excreted by the fish and unconsumed feed into coastal water results in such nutrients being deposited and accumulated in the sediment. Subsequently, this continuous accumulation triggers the release of ammonium ions during organic matter decomposition, and the ammonium-enriched waters that encroach on fish farms as influent seem to be due to the diffusion of high concentrations of ammonium from bottom sediment. Furthermore, we used fluorescence indices to examine the characteristics of organic matter sources, obtaining mean values of 1.54±0.19, 1.06±0.06, and 1.56±0.06 for the humification index, biological index, and fluorescence index, respectively, in the effluent. These results indicate that the organic matters had an autochthonous origin that resulted from microbial decomposition, and such organic matters were rapidly generated and removed by biological activity, likely supplied from the sediment. Our results suggest that the effluent from land-based fish farms could be a potential source of deoxygenation occurrence in coastal areas.

A Task and Valuation on Farm Animal Welfare for Organic Livestock (유기축산을 위한 농장동물복지의 과제와 평가)

  • Yoo, Duck-Ki
    • Korean Journal of Organic Agriculture
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    • v.15 no.3
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    • pp.237-256
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    • 2007
  • Organic farming is promoted financially in the Republic of Korea since 2000. The, entire segment shows a very dynamic development since that time. Now, a large bouquet of measures are offered which target the promotion of organic farming. This article presents a study about the Task and Valuation on farm animal welfare for Organic Livestock. Among the supports are grants for organically managed livestock farm, investment incentives, the promotion of organic livestock husbandry, the promotion of producer co-operatives, the development of farm animal right index for animal health and animal welfare, publicity measures and measures to raise consumer awareness as well as the support of training, extension and research in the field organic livestock farming. Government must ensure that necessary incentives and sanctions are in place to maintain and improve animal welfare standards and they must be delivered appropriately. Animal welfare legislation provides essential protection for economy, environment, animals and society as a whole, must be properly observed.

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Studies on the Correlation between SPF Index and Skin Irritation Index of Sunscreens (자외선 차단제의 SPF 지수와 피부자극지수와의 상관성 연구)

  • 김종원;서수경;최주영;박창원;서경원;김규봉;김광진;김재희;이선희
    • Biomolecules & Therapeutics
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    • v.10 no.4
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    • pp.246-252
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    • 2002
  • In recent years, the safety of sunscreens has been challenged based on the reports of their adverse effect on users; dermatitis, allergic contact dermatitis and photo allergic contact dermatitis. The unscientific idea that higher SPF sunsreen is good for health mealeads many users to tend to prefer higher SPF sunscreen. In the toxicological aspect, the need to investigate the safety of sunscreens is steadily increasing. However, there were few studies on the correlation between sun protection factor (SPF) and the safety of sunscreens. The objective of this study was to assess whether there was a correlation between SPF and the safety of sunscreens. We measured in vitro SPF index using homosalate as a standard and examined the toxicity tests such as primary skin irritation tests, ocular irritation test and skin sensitization test. Homosalate (HS), octyl methoxycinnamate (OMC), octyl salicylate (OS), octocrylene (OC) as UVB organic filter and benzophenone-3 (BP3), butyl methoxy dibenzoil methane (BMDM) as UVA organic filter, and titanium dioxide (TD), zinc oxide (ZO) as inorganic filters were used. The skin irritation indexes in rabbits treated with HS, OMC, OS, BP3, and BMDM were significantly increased as SPF indices were increased. Neither ocular irritation in rabbits nor skin sensitization in guinea pigs were increased. It suggests that there might be a good correlation between SPF and the skin irritation indices of organic UV filters and skin irritation might be one of most sensitive index to assess the safety of sunscreens.

Distribution Patterns of the Organic Pollution Indicators at Subtidal on Coast Developmentsin Korea (국내 연안개발에 따른 조하대 유기물 오염지표종 분포 연구)

  • Han, Hyoung-Sum;Lee, Seung-Hyun;Kim, Jong-Chun;Son, Dae-Sun;Ma, Chae-Woo
    • Journal of Environmental Impact Assessment
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    • v.29 no.2
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    • pp.112-121
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    • 2020
  • Organic pollution due to coastal development increases the distribution of organic pollution indicators (OPI) and disturbs benthic ecosystems by increasing the number of organic pollution indicators dominant in the target area. However, there is a little researches on the organic pollution levels of benthic ecosystems in subtidal target coast of all over Korea. Therefore, this study analyzed the distribution of macrobenthos in subtidal around the coast development sites of EIA, confirmed the distribution of OPI, and produced the benthic health index-map (organic pollution level) of all coasts of Korea. The benthic health index of the sites was calculated using the density of each OPI, and the image program was used for the benthic health index-map. Organic pollution levels varied by projects for EIA and OPI. Lumbrineris sp. was found to be dominant throughout the coast and correlated with the benthic health index in Korea. Through this study, we will be able to confirm the future organic pollution level in the subtidal ecosystems of the project for EIA through the results of research to macrobenthos in subtidal for EIA. In addition, the distribution of Lumbrineris sp. OPI can be used as an indicator to indirectly evaluate the organic pollution level of the development site.

Comparative Insect Biodiversity Analyses on the Agricultural Ecosystems of Goesan District of Korea (괴산군 지역 농업 생태계의 곤충 다양성 비교 분석)

  • Kim, Hoon;Sun, Yan;Lee, Seung-Min;Ku, Bon-Jin;Ku, Yun-Mo;Kim, Tae-Yeon;Moon, Myung-Jin
    • Korean Journal of Organic Agriculture
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    • v.29 no.4
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    • pp.539-559
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    • 2021
  • Agricultural ecosystem biodiversity monitoring and community variation analysis of insects were conducted from 2016 to 2018 in selected conventional and organic farming fields in Goesan district, Chungcheongbuk-do, South Korea. The total number of 1,125 species in 16 orders and 207 families were identified. The numbers of species collected in the locations practicing organic farming were greater than the conventional farming both in the paddy fields (564 vs. 383 species) and the upland fields (471 vs. 365 species). Among them, Hemiptera had the most abundant of species, followed by Diptera, Hymenoptera, Coleoptera and Araneae. We calculated various index values of biodiversity (diversity index H', richness index R, evenness index J', dominance index D, and similarity index QS) based on quantitative measurements of species and individuals collected over three years of field monitoring. Variations in biodiversity index values in different agricultural systems show that the positive effect of organic farming is to produce more biodiversity than conventional farming systems. When compared to other index results reported in Korea, Japan and China, the richness index was higher and other index values were at similar levels.