• Title/Summary/Keyword: landscape index

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The Spatial Distribution Analysis of Coastal Wetland Vegetation in Sihwa Lake (시화호 연안습지 식생의 공간 분포 분석)

  • Jeong, Jong-Chul;Cho, Hong-Lae
    • Journal of Environmental Impact Assessment
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    • v.17 no.2
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    • pp.105-112
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    • 2008
  • Human activity has been the major threat to wetlands. Agriculture, industrial development, and urban and suburban sprawl have caused the greatest losses of coastal wetlands. In fact, riceland agriculture, because of the flooding that goes with it, provides some additional wetland habitat not otherwise available. The biggest current source of loss for freshwater coastal wetlands is from urban sprawl. In this study, spatial analysis method such as landscape index were applied to Sihwa area in Ansan city. The SMA (Spectral Mixture Analysis) method using Landsat image showed the change distribution of wetland vegetation from 1996 to 2004. The southern part of Sihwa wetland have been changed with Suda japonica of 24% and reed vegetation of 34% on coastal wetland which were covered with tidal flat.

A Study on a Landscape Structure as a Change of Impervious Cover Rate in the Osan-cheon Watershed (오산천 유역의 불투수면 비율 변화에 따른 경관구조 분석)

  • Jang, Su Hwan
    • Journal of Environmental Impact Assessment
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    • v.17 no.5
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    • pp.289-297
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    • 2008
  • An impervious cover is one of most important factors which effect on a water body environment in a watershed. There are many researches on the impact of an impervious cover on water quality, quantity and ecosystem and most of these researches have been focused on an impervious rate or area in a watershed without considering structure features as like shape, edge, connection of impervious cover. In this study, we focused on a landscape structure which includes shape, density, contiguity, distance, aggregation of land cover type as well as area and rate. The calculation of a landscape indices made to analyse a landscape structure is conducted by applying Fragastats 3.3 program. Osan-cheon watershed where has rapidly urbanized is selected as a study field. Land information for 2002 and 2007 is from land classification maps provided by Ministry of Environment. The result shows that the increasing rate of an impervious cover is more conspicious in Kiheung dam watershed but the fragment of impervious cover areas is shown remarkably in the Osan sub-watershed. The trend of aggregation and connection of impervious covers is increasing. But it was very difficult to say that which type of landscape structure is more beneficial for a watershed management. The implication of this study is to find the need to come over the conventional ways to evaluate landscape structure of a watershed such as rates and areas of impervious cover, and define the importance of landscape feature as like connection, distance, edge density, fragment of impervious covers.

Patterns of Forest Landscape Structure due to Landcover Change in the Nakdong River Basin (토지이용변화에 따른 낙동강 유역 산림경관의 구조적 패턴 분석)

  • Park, Kyung-Hun;Jung, Sung-Gwan;Kwon, Jin-O;Oh, Jeong-Hak
    • Journal of Korean Society of Rural Planning
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    • v.11 no.4 s.29
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    • pp.47-57
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    • 2005
  • The goal of this research is to evaluate landscape-ecological characteristics of watersheds in the Nakdong River Basin by using Geogaphic Information System (GIS) and landscape indices for integation of spatio-temporal informations and multivariate statistical techniques for quantitative analysis of forest landscape. Fragmentation index and change matrix techniques using factor analysis and grid overlay method were used to efficiently analyze and manage huge amount of information for ecological-environmental assessment (land-cover and forest landscape patterns). According to the results based on the pattern analysis of land-cover changes using the change detection matrix between 1980s and 1990s, addition on 750km$^2$ became urbanized areas. The altered 442.04km$^2$ was agricultural areas which is relatively easy for shifting of land-use, and 205.1km$^2$ of forests became urbanized areas, and average elevation and slope of the whole altered areas were 75m and 4$^{\circ}$. On the other hand, 120km$^2$ of urban areas were changed into other areas (i.e., agricultural areas and green space), and fortunately, certain amount of naturalness had been recovered. But still those agricultural areas and fallow areas, which were previously urban areas, had high potential of re-development for urbanization due to their local conditions. According to the structural analysis of forest landscape using the landscape indices, the forest fragmentation of watersheds along the main stream of the Nakdong River was more severe than my other watersheds. Furthermore, the Nakdong-sangju and Nakdong-miryang watersheds had unstable forest structures as well as least amount of forest quantity. Thus, these areas need significant amount of forest through a new forest management policy considering local environmental conditions.

Landscape Scale Ecosystem Evaluation for Sustainable Landuse Planning (지속가능한 토지이용을 위한 경관규모 생태계평가기법 연구)

  • Hwang, Kook-Woong;Park, So-Yoon
    • Journal of the Korean Association of Geographic Information Studies
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    • v.6 no.1
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    • pp.78-84
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    • 2003
  • The purpose of this study is to evaluate the ecosystem soundness in landscape scale using landscape indices, and to extract regional information that can be used for sustainable landuse planning. About BongWha-gun, the landcover classification using Landsat TM images and patch analysis ware carried out, and some landscape indices were calculated using geographic information system(GIS) and patch analyst program. As the results of this study, Seokpo, Jaesan and Sochun got higher scores in landscape indices related to the ecosystem soundness. But, Bonghwa-eup got lowest scores in the 10 regions. When compared with normalized difference vegetation index(NDVI), this result showed consistency to some degree. Although, there needs more supplementary studies, it is anticipated that landscape scale ecosystem evaluation using landscape indices can gives us some informations related to sustainable landuse planning.

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Analyzing Change of Discomfort Index for Transpiration of Street Tree (도시 가로수의 증산 작용으로 인한 불쾌지수 변화 분석)

  • Yun, Seok-Hwan;Lee, Dong-Kun;Park, Chae-Yeon
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.23 no.5
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    • pp.29-43
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    • 2020
  • Thermal environment of city is getting worse due to severe urban heat island caused by climate change and urbanization. The cooling effect of street tree is regarded as a effective way to ameliorate the urban heat environment. The effect is largely made up of shadow formation and transpiration. This study aims to identify how the transpiration affects the discomfort index by analyzing comprehensive impact of the transpiration on the air temperature and relative humidity. The changes in the amount of transpiration, air temperature, and relative humidity were estimated for Seogyo-dong area which has a lot of floating population in Seoul, at 2 p.m. in dry day in July and August. On average, the transpiration of the street tree decreased the temperature 0.3℃ and increased the relative humidity 2.6% in an hour. As a result of these changes in temperature and humidity, the discomfort index rose mostly(0.036 on average). It was always get rise especially on the day when the discomfort index was above 80(0.05 on average). However, compared with the significant change in temperature and humidity, the variation of the discomfort index itself was very slight(up to 0.107). Therefore, the effect of transpiration by the street trees might not be effective in the planning to improve the thermal environment(especially on the day when the discomfort index is high). It is necessary to select the species of trees and planting location considering the cooling effect of shade formation synthetically.

Effects of Underground Container Types on Plant Growth of Viburnum odoratissimum var. awabuki and Quercus glauca (아왜나무와 종가시나무의 생육에 대한 지중매입형 컨테이너의 효과)

  • Choi, Su-Min;Shin, Hyeon-Cheol;Huh, Keun-Young;Jeong, Hyeon-Jong
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.15 no.3
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    • pp.67-74
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    • 2012
  • This study was carried out to cultivate evergreen-leaved tree container seedlings having low cost of equipment and easy to control. Two species of V. odoratissimum var. awabuki and Q. glauca planting in respective underground container were showed survival rate above 90%. The Relative growth rates of height was good in non-treatment and root collar diameter was no significant difference between treatments. The T/R ratio was respectively 1.1, 1.0 in container type of F, G. and root's biomass products was more effective than others. A container type of F showed better Quailty index than others with 16.2 values. Q. glauca was higher T/R ratio in root development than shoot and the quality index was high in container type of E, D with 4.0. 3.5, respectively. On the basis of the results obtained in this study, we can concluded that the underground container type was suitable to F in V. odoratissimum var. awabuki and to D or E in Q. glauca.

Assessment of the Distribution of the Street Trees of Suwon City for Biodiversity

  • Choi, Sun A;Kim, Shin Won
    • KIEAE Journal
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    • v.14 no.5
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    • pp.49-57
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    • 2014
  • This research is about analysis and evaluation of biodiversity of Suwon's street tree, then understanding the problem of it and finally finding a solution. Because the increasing damage of the street trees by disease and insects, insecticide is applied to prevent further damage. However, this insecticide is found to be cancer genic and causing hygienic threat to civilians. Therefore, by gathering Suwon's internal statistics about Suwon's street tree, the trees are divided into three categories, tall evergreen trees, deciduous trees, shrubs following Frank's 30-20-10 theory(1990). Also, according to species diversity index, the problem of disease and insect is researched in terms of biodiversity, and here we suggests solutions to counter such problems. According to the results, the trees planted in Suwon was found to be 31 families, 43 genus and 58 species. The most used kinds, almost 85% of the whole species, are found to be Rhododendron indicum (L.) Sweet, Buxus koreana Nakai ex Chung & al, Euonymus japonicus Thunb, Ligustrum obtusifolium Siebold & Zucc. Besides these, the rest of 15% of street trees had little variety. Therefore, it is necessary to plant tree variously and equally in terms of biodiversity. If this Frank's 10-20-30 solution is not enough to completely solve coulure problem, then further research will be done on soil properties, and local features for improvement of Suwon street tress.

A Study on the Analysis of Connectivity for Green Space Planning in Daejeon Metropolitan City (대전시 녹지계획을 위한 연결성 분석에 대한 연구)

  • Cheong, Yong-Moon;Kim, Sun-Tae;Kim, Myoung-Soo
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.5 no.6
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    • pp.14-23
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    • 2002
  • Daejeon is a large city in Korea and very high-speedly developing city. Recently urban area is expanding and large forest patch is fragmenting into small habitats because of urban sprawl. The fragmentation of large forest patch decreases the size of habitats and increases the loss of biodiversity in urban area. This study is to analysis the connectivity of green space of Daejeon metropolitan city, and suggest the optimum location of greening site and corridor in order to increase the connectivity of green space of Daejeon metropolitan city. The findings of this study are as follows; (1) The result of this study showed that ${\alpha}$ and ${\gamma}$ index are -0.24 and 0.20. A ${\alpha}$ index is very low and a ${\gamma}$ index is relatively low. (2) The dispersion was very high, for urban forest patches were isolated through fragmentation. Therefore, it needed ecological corridors in order to connect the patches. (3) A urban streams were very important in connectivity of urban green space. Urban riparian corridor must be preserved and restored. (4) A urban green space policy and planning must be prepared to increase the connectivity and assessment of alternatives must be accomplished from perspective of connectivity. The results of this study show the practical implications in perspective of green space planning and policy in Daejeon metropolitan city. The suggestions by findings of this study are to connect green space between large forest patch in urban fringe and island green space in inner city. Also, It is required that urban stream is restored to natural feature for use of corridor by wildlife.

The Appropriate Mounding Height and Selection of Ornamental Trees on the Considering of Environmental Characteristics in the Apartment Complex - In the case of Sanggyoi-Dong Sanitary Sandfill - (생육환경특성을 고려한 아파트단지내 조경수목 선정 및 적정 성토높이 - 상계동 쓰레기 매립지를 중심으로 -)

  • Lee, Kyong-Jae;Han, Bong-Ho;Cho, Woo
    • Korean Journal of Environment and Ecology
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    • v.11 no.1
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    • pp.137-148
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    • 1997
  • This study was conducted to select appropriate woody species and to propose appropriate woody species and to propose appropriate mounding hight through analysis of soil characteristics, planting state, draining state, growth amount and injured index of woody species. Soil acidity was pH 5.9~7.4, as alkaline soil. The state of draining was proved to be inappropriate for the growth of woody species because of bad draining state. Injured index of woody species were Prunus serrulata var, spontanea in deciduous tree because of polluted water leaked from sanitary landfill and density of planting tree. Appropriate mounding heignt of the planted area which was itensive injured wood species was not less than 80cm. Appropreate woody species in wanggyoi-dong apartment complex were Zelkova serrata, Acer trifloum, Acer buergerianum, Sophora japonica, Ailanthus altissima and appropriate mounding height was not less than 50~60cm.

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Dynamics of Forest Community Structure at the Valley of Piagol and Daeseonggol in the Jirisan National Park(I) (지리산국립공원 피아골과 대성골 지역의 산림군집구조 동태(I))

  • Oh, Koo-Kyoon;Kim, Yong-Shik;Oh, Jang-Guen;Ki, Young-Bum
    • Korean Journal of Environment and Ecology
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    • v.22 no.5
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    • pp.514-520
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    • 2008
  • The permanent monitoring plots were installed in 2001 for long-term monitoring the structure of forest communities at the Piagol(Valley) and Daeseonggol(Valley) in the Jirisan National Park, and monitored the forest structure in the studied sites in 2001 and 2006. Dominant species at Piagol and Daeseonggol was Carpinuslaxiflora and Quercus mongolica respectively. Based on the distribution of major species' stem diameter, the species diversity index was higher in Piagol than that of Daeseonggol. The distribution of diameter in major tree species in the studied sites showed a stable plant community structure. The forest of Piagol, which is positioned in the valley, showed a quite a different composition of species from that of Daeseonggol, which is positioned on the slope. In the last five years, the overall grows rate of Piagol Forest decreased by $6.4m^2$ per hectare, while Daeseonggol Forest increased by about $8.27m^2$ per hectare. I think that this is because of the fact that a lot of large old trees have died.