• 제목/요약/키워드: Anthropogenic Factors

검색결과 174건 처리시간 0.026초

Spatio-Temporal Distributional Changes of Bamboo (대나무의 시.공간적 분포역 변화)

  • 공우석
    • Journal of the Korean Geographical Society
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    • 제36권4호
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    • pp.444-457
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    • 2001
  • Present work aims to analyse the spatio-temporal distribution of Korean bamboos. The northern limit of Korean bamboo species occurs at Baekryung Island(124°10'E, 37°55'N), Hoochang(41°22'N) and Myungchon(129°41\`E, 41°10'N). The presence of bamboo fossils in Korea dates back from Tertiary, but widespread use of bamboos can be noticed since 1454. Reconstructed ranges and temporal changes of bamboo, based upon the eight historical records from 15th to 20th centuries, indicates that both climatic and anthropogenic factors were responsible for the changes of distributional range. The spread of bamboos was balanced by its disappearance due to regional development, and the total bamboo area showing little change. Due to the tendency to spread extensively by means of underground stems, bamboos often invade adjacent forests and disturb natural vegetation. Proper management and conservation strategies, therefore, are required for the maintenance of rural landscape.

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Occurrence of Vanadium in Groundwater of Jeju Island, Korea (제주도 지하수 내 바나듐의 산출 특성)

  • Hyun, Ik-Hyun;Yun, Seong-Taek;Kim, Ho-Rim;Kam, Sang-Kyu
    • Journal of Environmental Science International
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    • 제25권11호
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    • pp.1563-1573
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    • 2016
  • The aim of this study was to evaluate the occurrence of vanadium in Jeju Island groundwater, focusing on the spatio-temporal patterns and geochemical controlling factors of vanadium. For this, we collected two sets of groundwater data: 1) concentrations of major constituents of 2,595 groundwater samples between 2008 and 2014 and 2) 258 groundwater samples between December 2006 and June 2008. The concentrations of groundwater vanadium were in the range of $0.2{\sim}71.0{\mu}g/L$ (average, $12.0{\mu}g/L$) and showed local enrichments without temporal/seasonal variation. This indicated that vanadium distribution was controlled by 1) the geochemical/mineralogical composition and dissolution processes of original materials (i.e., volcanic rock) and 2) the flow and chemical properties of groundwater. Vanadium concentration was significantly positively correlated with that of major ions ($Cl^-$, $Na^+$, and $K^+$) and trace metals (As, Cr, and Al), and with pH, but was negatively correlated with $NO_3-N$ concentration. The high concentrations of vanadium (>$15{\mu}g/L$) occurred in typically alkaline groundwater with high pH (${\geq}8.0$), indicating that a higher degree of water-rock interaction resulted in vanadium enrichment. Thus, higher concentrations of vanadium occurred in groundwater of $Na-Ca-HCO_3$, $Na-Mg-HCO_3$ and $Na-HCO_3$ types and were remarkably lower in groundwater of $Na-Ca-NO_3$(Cl) type that represented the influences from anthropogenic pollution.

The Metallic Elements of PM10 and PM2.5 in Western Region of Busan in the Springtime of 2005 (2005년 봄철 부산 서부지역 PM10, PM2.5의 금속성분 특성)

  • Jeon, Byung-Il
    • Journal of Environmental Impact Assessment
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    • 제16권5호
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    • pp.327-340
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    • 2007
  • The $PM_{10}$ and $PM_{2.5}$ aerosols were collected at Busan from March to May, 2005, and the concentrations of some metallic elements were analysed to study their characteristics. The mean concentration of $PM_{10}$ was $66.5{\pm}23.0{\mu}g/m^3$ with a range of 22.2 to $118.1{\mu}g/m^3$. The mean concentration of $PM_{2.5}$ was $46.1{\pm}17.2{\mu}g/m^3$ with a range of 9.7 to $83.3{\mu}g/m^3$. The ratio of $PM_{2.5}/PM_{10}$ was 0.69 at Busan. The distribution of metallic elements for $PM_{10}$ and $PM_{2.5}$ were Cd${\ldots}$ ${\ldots}$ $PM_{10}$ were $94.9{\mu}g/m^3$ and $63.7{\mu}g/m^3$, respectively. And The mean mass concentrations of Asian dust and non Asian dust in $PM_{2.5}$ were $56.9{\mu}g/m^3$ and $45.1{\mu}g/m^3$, respectively. The mean values of crustal enrichment factors for five elements (Cd, Cu, Pb, V and Zn) were all higher than 10, possibly suggesting the influence of anthropogenic sources. The soil contribution ratios for $PM_{10}$ and $PM_{2.5}$ were 20.5% and 19.4, respectively.

Watershed Classification Using Statistical Analysis of water Quality Data from Muju area (무주지역 수질특성자료의 통계학적 분석에 의한 소유역 구분)

  • 한원식;우남칠;이기철;이광식
    • Journal of Soil and Groundwater Environment
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    • 제7권3호
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    • pp.19-32
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    • 2002
  • This study is objected to identify the relations between surface- and shallow ground-water and the seasonal variation of their qualities in watersheds near Muju area. The water type shows mainly Ca-$HCO_3$type. Heavy-metal contamination of surface water is locally detected, due to the mixing with mine drainage. In October nitrate concentration is especially high in densely populated area. Cluster Analysis and Principal Component Analysis are implemented to interpret the complexity of the chemical variation of surface- and ground-water with large amount of chemical data. Based on the cluster analysis, surface-water was divided into five groups and ground-water into three groups. Principal Component Analysis efficiently supports the result of cluster analysis, allowing the identification of three main factors controlling the water quality. There are (1) hydrogeochemical factor, (2) anthropogenic factor and (3) heavy metal contaminated by mine drainage.

Cytochrome oxidase subunit I (COI) DNA sequence divergence between two cryptic species of Oryzias in South Korea

  • In, Dong-Su;Choi, Eun-Sook;Yoon, Ju-Duk;Kim, Jeong-Hui;Min, Jun-Il;Baek, Seung-Ho;Jang, Min-Ho
    • Journal of Ecology and Environment
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    • 제36권3호
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    • pp.159-166
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    • 2013
  • Oryzias latipes and Oryzias sinensis are indigenous species found in Japan, China, and other East Asian countries, including Korea. Based on morphological differences, the species have been classified distinctly. However, the range of morphological characters such as the number of gill rakers, vertebrae, and spots on the lateral body overlaps and is too vague for clear identification, so their classification based on their morphological characteristics remains uncertain. In this study, the mitochondrial cytochrome oxidase subunit I (COI) gene, which is used for DNA barcoding, was applied to clarify interspecific variation of O. latipes and O. sinensis. Intraspecific genetic diversity was calculated to identify correlations with geographic distributions. We studied two species collected from 55 locations in Korea. All individuals carried a 679-base pair gene without deletion or insertion. Between species, 525 base pairs of the gene were shared. The Kimura two parameter (K2P) distance of O. latipes and O. sinensis was 0.41% and 1.39%, respectively. Mean divergence within genera was 23.5%. Therefore, the species were clearly different. The distance between O. latipes and O. sinensis was 14.0%, which is the closest within genera. Interestingly O. latipes from the Japanese and Korean group represented 16.5% distant. These results were derived from geohistorical and anthropogenic environmental factors. The O. latipes haplotypes were joined in only one group, but O. sinensis was divided into two groups, one is found in the Han River and upper Geum River watershed; the other is found in the remaining South Korean watersheds. Further studies will address the causes for geographic speciation of O. sinensis haplotypes.

Characteristics of Fine Particles Measured in Two Different Functional Areas and Identification of Factors Enhancing Their Concentrations (강원도 춘천과 영월에서 측정한 미세먼지 농도 특성 및 고농도 원인 분석)

  • Cho, Sung-Hwan;Kim, Hyun-Woong;Han, Young-Ji;Kim, Woo-Jin
    • Journal of Korean Society for Atmospheric Environment
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    • 제32권1호
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    • pp.100-113
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    • 2016
  • In this study, the characteristics of $PM_{2.5}$ and $PM_{2.5-10}$ concentrations were identified in two different functional areas including Chuncheon and Youngwol, Korea. Even though the anthropogenic emission rates of $PM_{2.5}$ and $PM_{10}$ are approximately four times higher in Youngwol than in Chuncheon their atmospheric concentrations were statistically higher in Chuncheon. In Chuncheon, both $PM_{2.5}$ concentrations and the ratio of $PM_{2.5}/PM_{10}$ increased as relative humidity (RH) increased possibly because the inorganic and/or organic secondary aerosols were actively formed at high RH. This result was also supported by that $PM_{2.5}$ concentration was enhanced under the fog and mist conditions in Chuncheon. On the other hand, both $PM_{2.5}$ and $PM_{2.5-10}$ concentrations clearly increased with the southerly winds blown from the cement production facility in Youngwol. In addition, high $PM_{2.5-10}$ concentrations were observed with high wind speed, low relative humidity, and high $NO_2$ concentrations in Youngwol, suggesting that $PM_{2.5-10}$ was generated through the physical process including crushing and packing procedures followed by resuspension from cement and lime factory.

Heavy Metals in Surface Sediments from Kwangyang Bay, South Coast of Korea (광양만 표층퇴적물의 중금속 함량 및 분포)

  • Lee, Chang-Bok;Koh, Chul-Hwan;Cho, Yeong-Gil
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • 제5권2호
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    • pp.131-140
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    • 2000
  • Heavy metals (Fe, Mn, Cr, Co, Cu, Ni, Zn, Pb) were determined in ninety-one surface sediments collected from Kwangyang Bay, south coast of Korea. The data show that the Fe, Cr, Ni, and Zn distribution in the bay can be described by metal vs. grain size relationship. However, the distribution pattern of Mn, Co, Cu and Pb were found to be changed because they are anthropogenically enriched to sediment. Correlation matrix and R-mode factor analyses revealed that two important factors controlling the distribution of metals in the bay are grain size and anthropogenic input.

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Water Quality Properties of Tributaries of Daechung Lake, Korea (대청호 유입지천의 수질 특성)

  • Shim, Moo Joon;Yoon, Jae Yong;Lee, Soo Hyung
    • Korean Journal of Ecology and Environment
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    • 제48권1호
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    • pp.12-25
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    • 2015
  • The tributaries of Daechung Lake play an important role in controlling eutrophication in the lake, which is used for agricultural purposes and as potable water. However, water quality properties were not extensively studied in the tributaries of Daechung Lake. The objectives of this study are to investigate spatial and temporal properties of water quality and to characterize streams which could threaten water quality of Daechung Lake. For this study, water samples were weekly or monthly collected from February 2014 to October 2014 in 9 streams. Water quality parameters analyzed in this study include biochemical oxygen demand (BOD), chemical oxygen demand (COD), total organic carbon (TOC), total nitrogen and phosphorus (TN and TP), suspended solids (SS), and chlorophyll a. Based on temporal distribution and principal component analysis, BOD, COD, TOC, SS, and TP were controlled by not only river discharge that increased during summer due to heavy rain fall, but also due to anthropogenic input (e.g., bridge construction and/or agricultural activity). Dilution is also one of the factors explaining TN and conductivity, both of which decreased with increased discharge. Generally, concentrations of contaminants (BOD, COD, TOC, TN and TP) in the tributaries were higher than those of Daechung Lake. However, pollution load indicated that only the main channel of Geum River and Sook Stream may largely influence lake waters, attributed mostly to their large volumes. This implies that the main channel and Sook Stream are the major influences on the water quality of Daechung Lake.

Assessment of the Pollution Levels of Organic Matter and Metallic Elements in the Intertidal Surface Sediments of Aphae Island (압해도 조간대 표층퇴적물의 유기물 및 금속원소 오염도 평가)

  • Hwang, Dong-Woon;Park, Sung-Eun;Kim, Pyoung-Jung;Koh, Byoung-Seol;Choi, Hee-Gu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • 제44권6호
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    • pp.759-771
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    • 2011
  • We evaluated the pollution levels of organic matter and metallic element (Fe, Cu, Pb, Zn, Cd, Ni, Cr, Mn, As, and Hg) in the intertidal surface sediments of Aphae Island using several sediment quality guidelines (SQGs) and assessment techniques for sediment pollution. Based on the textural composition of sediment, the surface sediments were classified into two main sedimentary facies: slightly gravelly mud and silt. The concentrations of chemical oxygen demand (COD) and acid volatile sulfide (AVS) in the sediments ranged from 4.6-9.9 (mean $7.4{\pm}1.1$) $mgO_2/g{\cdot}dry$ and from ND-0.53 (mean $0.04{\pm}0.10$) mgS/$g{\cdot}dry$, respectively. These values were considerably lower than those reported from a farming area in a semi-enclosed bay of Korea and for SQGs in Japan. The metallic element concentrations in the sediments varied widely with the mean grain size and organic matter content, implying that the concentrations of metallic elements are influenced mainly by secondary factors, such as bioturbation, the resuspension of sediment, and anthropogenic input. The overall results for the comparison with SQGs, enrichment factor (EF), and geoaccumulation index ($I_{geo}$) indicate that the surface sediments are slightly polluted by Cr and Ni, and moderately polluted by As. Our results suggest that the intertidal surface sediments of Aphae Island are not polluted by organic matter or metallic elements and the benthic conditions are suitable for healthy organisms.

Species Alterations Caused by Nitrogen and Carbon Addition in Nutrient-deficient Municipal Waste Landfills

  • Kim, Kee-Dae
    • Journal of Ecology and Environment
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    • 제30권2호
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    • pp.161-170
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    • 2007
  • The ultimate target of restoring waste landfills is revegetation. The most effective method for increasing species richness and biomass in nutrient limited waste landfills is the use of fertilizers. The aim of the present study was to investigate the effects of nitrogen fertilizer, and the addition of carbon through sawdust, sucrose and litter, on vegetation dynamics at a representative municipal waste landfill in South Korea: Kyongseodong. A total of 288 permanent plots $(0.25m^2)$ were established and treated with nitrogen fertilizer (5, 10 and $20Ng/m^2$), sawdust $(289g/m^2)$ sucrose $(222g/m^2)$ and litter $(222g/m^2)$. The aboveground biomass was significantly enhanced by nitrogen fertilizer at 5 and $10Ng/m^2$, compared with the control plots. The total cover of all plant species increased significantly on plots treated with 5 and $20Ng/m^2$, as well as on those treated with sawdust and sucrose, compared with the control plots. The higher species richness after nitrogen fertilization of 10 to $20Ng/m^2$, and the sawdust and sucrose treatment demonstrated that this was an appropriate restoration option for nutrient deficient waste landfills. This study demonstrated positive nutrient impacts on plant biomass and species richness, despite the fact that municipal waste landfills are ecosystems that are highly disturbed by anthropogenic and internal factors (landfill gas and leachate). Adequate N and C combined treatments will accelerate species succession (higher species richness and perennial increase) for restoration of waste landfills.