• Title/Summary/Keyword: Coastal vegetation

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Flow Resistance Analysis for Lower Naesung Stream Considering Grain and Bedform Roughness (사립조도와 하상형상조도를 고려한 내성천 하류의 흐름저항 분석)

  • Ji, Un;Kim, Ji-Sung;Lee, Chan Joo
    • Journal of Korea Water Resources Association
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    • v.46 no.12
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    • pp.1209-1220
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    • 2013
  • Roughness coefficients calibrated by flow modeling using the 1-dimensional numerical model were analyzed for the downstream section of Naesung Stream in this study. Also, the bedform configuration at the Hyangseok Station was predicted for measured and simulated hydraulic conditions of flows and total flow roughness was estimated with the coefficient of grain roughness. The Manning's n coefficients calibrated by numerical modeling and estimated by considering of grain and bedform roughness were compared and examined. As a result, the Manning's n by numerical modeling was greater than the coefficient range estimated by grain and bedform roughness at the low flow regime due to the other factors such as vegetation, sinuosity, and sand bar. However, the Manning's n by numerical modeling was included in the coefficient range by grain and bedform roughness at the transition and high flow regime over $500m^3/s$ of flow discharge.

Enhancing LANDSAT TM to update the structural analysis of the Mirs Bay Basin, Hong Kong, China

  • Leung, K.F.;Vohora, V.K.;Chan, L.S.;Malpas, J.G.
    • Proceedings of the KSRS Conference
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    • 2003.11a
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    • pp.295-297
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    • 2003
  • The coastal provinces of South China have been uniquely shaped by various tectonic events. During the midlate Mesozoic tectono-thermal event, the oblique subduction of the Paleo Kula-Pacific plate beneath the Eurasian plate has created a complicated tectonic setting for the whole region. However, the mechanism of this event is not completely understood. In this paper, we discuss the advantages of using LANDSAT TM satellite imagery over a small part of the region - the Mirs Bay Basin which is largely covered by dense vegetation and where limited outcrops is seen. The use of satellite imagery complements field mapping and the result shows a prominent sinistral offset along the eastern margin of the Mirs Bay Basin, which was not previously recognized on the ground.

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Distribution of Azotobacter in Rhizosphere and Sea (Rhizosphere와 해수에 있어서의 Azotobacter의 분포)

  • 홍순우;최영길
    • Korean Journal of Microbiology
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    • v.12 no.1
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    • pp.15-24
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    • 1974
  • This experiment has been carried out with a view to elucidating the distribution of Azotobacter and their population size in rhizosphere and sea and designed ro compare the results with some environmental factors. Results of the experiment are summarized as follows: 1) It was observed that the population sizes of Azotobacter were decided upon the moisture content of soil and that the soil pH was one of the most impertant factors influencing the distribution of Azotobacter. 2)Population sizes of Azotobacter in rhizosphere were changed in accordance with the kinds of vegetation on soil: The rhizosphere where bamboo, corn, legume, and oak inhabit showed the largest population size of Azotobacter. On the other hand, rhizosphere of ginseng revealed no Azotobacter. However, the largest population of general fungi were measured at the rhizosphere. 3)Comparing the population sizes of general microbes in rhizosphere with those of non-rhizosphere, the population sizes of microbes in rhizosphere are larger than those of non-rhizosphere. 4)In coastal environments, population sizes of Azotobacter in surface water of sea are similar to those of the soil(mud) of tidal land. But the sizes are generally smaller than those of terrestrial soils.

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A Study on the Flora of Osik Island and its Neighboring Two Islands (筽篒度와 燐近 島嶼의 植物相에 關한 硏究)

  • Kim, Doo Young;Jeom Sook Lee
    • The Korean Journal of Ecology
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    • v.7 no.3
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    • pp.158-169
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    • 1983
  • An investigation on the floras of Osik island and its neighboring two islands, 13km west of Gunsan, showed that there were a total of 305 kinds belonging to 81 families, 132 genus, 259 species, 42 varieties, 4 formas. Of the 305 kinds collected 213 kinds were herb and 92 kinds were woody plant. Seven species of evergreen broad-leaved trees including Euonymus japonica T., Eurya japonica T. and Elaeagnus macrophylla T. etc. are listed in the Norae-sum and Ga-do. The vegetations of Norae-sum and Ga-do were more favorable than that of Osik-do which vegetation was destructed by human inerferences. Coastal plants in these areas were about 30 species. It is interest that the floras of these areas were very similar to that of Gogunsangun-do (r=0.97) inspite of adjacency to inland area.

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The Distribution Analysis of Coastal Wetland Vegetation Using Landscape Index (경관지수에 의한 연안습지 식생의 분포 분석)

  • Jeong, Jong-Chul;Cho, Hong-Lae
    • Proceedings of the KSRS Conference
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    • 2008.03a
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    • pp.39-43
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    • 2008
  • 경관을 구성하는 다양한 요소들의 공간적 분포 패턴과 상호 관계를 정량적으로 분석하기 위하여 다양한 경관지수가 개발되어 사용되고 있다. 경관구조 및 변화특성을 정량적으로 해석하기 위한 노력은 1950년대 후반부터 기하학적 이론을 기초로 하여 제기되어 왔으며, 최근에는 원격탐사, GIS, 정보이론, 프랙탈 이론에 근거한 지표 등이 도입되어 사용되고 있다. 본 연구에서는 연안습지 식생의 발달과 분포 특성을 공간적으로 해석하기 위해 Landsat 영상에 분광혼합분석 기법을 적용하여 선정한 지표면 식생비율을 10개 클래스로 구분한 후 각 클래스에 대해 경관지수를 적용하여 식생비율의 시-공간적 변동 특성을 분석하였다. 새만금방조제를 비롯한 많은 연안습지에 생성되는 습지식생의 공간적 분포를 변화탐지 하고 이들의 시-공간적 분포에 영향을 미치는 요인을 해석하여 연안습지의 보존과 개발에 대한 기초 정보를 위성자료를 통해 추출 분석하였다.

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Studies on the Environmental Changes with the Urbanization of Ansan City (안산시의 도시화에 따른 환경변화에 관한 연구)

  • Yim, Yang-Jai;Jeyong Kang
    • The Korean Journal of Ecology
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    • v.11 no.4
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    • pp.201-212
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    • 1988
  • Ansan city in the coastal area of the mid-western Korea is known as a newly industrialized city(73.44$Km^2$, 127, 000 persons), with the increase rate of 27.8% in population and mean density of 1, 732 persons/$Km^2$. According to the census of the city(1986), it consists of cultivated field(36.8%), forest(34.2%), industrial area(7.4%), residential area(4.1%) and others(12.5%). The forest vegetation in the city is composed of four associations and two subassociations as follows; Pinus rigida, Pinus densiflora-Rhododendron mucronulatum, Quercus mongolica-Rhododendron mucronulatum and Robinia pseudo-acacia asociation, and Quercus mongolica-Corylus sieboldiana var. mandshurica and Robinia pseudoacacia-Alnus hirsuta subassociation. Various environmental conditions have been changed with the progress of urbanization of the city, since 1977. For example, a heat island phenomenon, which is the air temperature of 2 or 3$^{\circ}C$ higher in the central area than that of the boundary area, and floral changes caused by air pollutants such as decreasing bryophyte species along increasing SO$_2$ concentration.

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Studies on Vegetation for Ecological Restoration of Salt Marshes in Saemangeum Reclaimed Land - Population Formation Strategies of Halophytes - (새만금 간척지일대 염습지 생태복원을 위한 식생학적 연구 -염생식물의 개체군 형성 전략-)

  • Kim, Chang-Hwan
    • Journal of Environmental Science International
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    • v.18 no.4
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    • pp.463-471
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    • 2009
  • A study on vegetation in the Mangyeong River and Dongjin River basins and the surrounding regions of the Saemangeum Reclaimed Land was conducted in a series of efforts to determine the expected ecological changes in the salt marshes, to restore their vegetation, to explore the restoring force of halophyte, to examine the community mechanism and, ultimately, to rehabilitate marshy land vegetation along the lakeside, coastal dune and salt marshes of the Saemangeum Project Area. The findings of the study may be summed up as follows: Five species such as Suaeda japonica, Salicornia herbacea, Atriplex gmelini, Aster tripolium and Suaeda asparagoides that are mostly distributed in the estuary of the Saemangeum Reclaimed Land were analyzed to examine the mechanism of halophyte to maintain their community. To find out the strategies of plants for survival and the cause of forming community structure, a research was made as for appearance ratio of biomass, root lengths and germination. With regard to biomasses of halophyte, the biomass of Suaeda japonica increases rapidly, while Salicornia herbacea adopts a strategy of unstable growth pattern by which the biomass increases slowly in parallel with its slow speed of growth since initial appearance of young sapling. In contrast, Suaeda asparagoides, Atriplex gmelini and Aster tripolium choose to adapt themselves to environment promptly by being transformed into life form of annual or biennial plant, a pattern that is presumed to be favorable and stable for survival in the later stage of growth. In short, there is a sharp distinction among the 5 species: i.e. Suaeda japonica that begins to grow fast in the length of surface and underground section but slows down from the mid-stage on; Salicornia herbacea that grows slowly in the beginning step but starts to step up from the middle onward; Atriplex gmelini and Aster tripolium growing slowly in the initial stage but fast later on; and Suaeda asparagoides that turns from the constant growth in the beginning to rapid growth in the later period. The outcomes of the analysis into status of growth and influencing factors of Suaeda japonica in the sowing field that is most widely prevalent in the Saemangeum Reclaimed Land as a sort of ecological pioneer in the salt marshes showed that the average size of grass lands, density and number of individuals increase in the natural sowing field as well as in the plowing field regardless of their physical as well as physico-chemical features of the soil as the season progresses from June to October of a year.

Syntaxonomical and Synecological Research of Forest Vegetation on Mt. Byeokbang (벽방산 산림식생의 군락분류와 군락생태)

  • Choi, Byoung-Ki;Huh, Man-Kyu;Kim, Seong-Yeol
    • Journal of Life Science
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    • v.25 no.6
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    • pp.646-655
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    • 2015
  • A phytosociological survey carried out using the Z.-M. School’s methodology and system of numerical-classification analyses, this study sought to classify the syntaxa of forest vegetation on Mt. Byeokbang and to collect basic data on the transitional zones of the southern Korean peninsula’s coastal region. The syntaxa were classified into three physiognomic types and nine communities, including (1) evergreen coniferous forests (Eurya japonica-Pinus thunbergii community and Ardisia japonica-Pinus densiflora community), (2) summer-green, broad-leaved forests (Chloranthus japonicus-Quercus serrate community, Syneilesis palmata-Quercus mongolica community, Quercus acutissima community, Carpinus turczaninovii var. coreana community, Fraxinus siebolidiana-Quercus dentate community, and Deutzia glabrata-Lindera erythrocarpa community), and (3) artificial afforestation (Alnus firma afforestation). The Chloranthus japonicus-Quercus serrata community, Syneilesis palmata-Quercus mongolica community, Fraxinus siebolidiana-Quercus dentata community, Carpinus turczaninovii var. coreana, community and Deutzia glabrata-Lindera erythrocarpa community were closely evaluated for national vegetation naturalness. It was confirmed that the Carpinus turczaninovii var. coreana community was endemic to Korea. Most syntaxa were defined as a secondary forestation due to various human activities (e.g., forest fires, logging, digging, climbing, etc.). The results of a canonical-correspondence analysis (CCA) showed that human activities, altitude, humus depth, rock cover ratio, slope, etc. were the main ecological factors determining the classified plant communities’ distribution patterns.

A Pilot Study on Environmental Understanding and Estimation of the Nak-Dong River Basin Using Fuyo-1 OPS Data (Fuyo-1 OPS 자료를 이용한 낙동강 하류지역의 환경계측 시고)

  • Kim, Cheon
    • Korean Journal of Remote Sensing
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    • v.12 no.2
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    • pp.169-198
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    • 1996
  • The objectives of this investigation are : 1. To analyze spectral signature and the associated vegetation index for geometric illumination conditions inf1uenced by low solar elevation and high slope orientations in mountainous forest. 2. To assess the accuracy of the spectral angle mapper classification for the a winter land cover in comparison with the maximum likelihood classification. 3. To produce the image of water quality and water properties that could be used to estimate the water pollution sources and the tide-included by turbid water in estuarine and coastal areas. These objectives are to characterize environmental and ecological monitoring applications of the Nak-Dong River Basin by using Fuyo-1 OPS VNIR data acquired on December 26, 1992. The results of this paper are as follows : 1. The spectral digital numbers and vegetation indexes (NDVI and TVI) of mountainous forest are higher on the slope facing the sun than on the slope hidden the sun under low sun elevation condition. 2. The spectral angle mapper algorithm produces a more accurate land cover classification of areas with steep slope, various aspects and low solar elevation than the maximum likelihood classifier. 3. The maximum likelihood classification images can be used for identifying the location and movement of both freshwater and salt water, regardless of geometric illumination conditions. 4. The color-coded density sliced image of selected water bodies by using the near-infrared band 3 can provide distribution of the water quality of the Lower Nak-Dong River. 5. The color-coded normalized difference vegetation index image of the selected mountain forest is suitable to classify winter vegetation cover types, i.e., forest canopy densities for slope orientations.