• Title/Summary/Keyword: Changes in vegetation

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Effect of a Sudden Increase in Light Intensity on Normalized Difference Vegetation Index (NDVI) Reflected from Leaves of Tobacco (급격한 광도 변화가 담배 잎에서 반사되는 Normalized Difference Vegetation Index에 미치는 영향)

  • Suh, Kyehong
    • Journal of Environmental Science International
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    • v.26 no.4
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    • pp.543-547
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    • 2017
  • Normalized Difference Vegetation Index (NDVI) has played an important role in assessing green plant biomass through remote sensing on global scale since the early 1970s. The concept of NDVI is based on the fact that green plants show higher reflection in near-infrared region than in visible region of the electromagnetic spectrum. However, it is well known that the relocation of chloroplasts in plant leaf cells may dramatically change the optical properties of plant leaves. In this study I traced the changes in the reflectance and transmittance properties of Tobacco leaves at the wavelengths of 660 and 800 nm after a sudden increase in light intensity. The results showed that NDVI of leaves gradually decreased from 72.7% to 69.9% when exposed to a sudden increase in light intensity from 30 to $1,200{\mu}mol/m^2{\cdot}s$. This means that the error resulting from the physiological status of the plant should be accounted for a more precise understanding of ground truth corresponding to the data from the remotely acquired images.

Analysis of LANDSAT Images of Estimated Vegetation Index and Paddy Area (수도경작지 식생변화 추정을 위한 여주, 양평, 광주 LANDSAT 데이터 분석)

  • Jung, Won-Kyo;Rim, Sang-Kyu;Shin, Jae-Sung
    • Korean Journal of Soil Science and Fertilizer
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    • v.30 no.2
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    • pp.135-139
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    • 1997
  • Vegetation indices were analyzed from the LANDSAT images of Yeoju, Kwangju and Yangpyong Gun of Kyunggi Province, obtained on September 22, 1983 and September 12, 1994, to evaluate the changes in landuses. It was found that there were notable changes in the landuses in the observed area over 11 years. Particularly, in Choweol Myun of Kwanju Gun, in Yangpyong Eup of Yangpyong Gun, and in Heungcheon Myun of Yeoju Gun, decrease in the area under vegetatin was most remarkable. These changes in the area under vegetatin are considered as the results of the construction of highways and the expansion of urban areas. The LANDSAT images overestimated the area under rice cultivation, when compared to the official statistic year book. However, it was found that the areas of the land under rice cultivation estimated by LANDSAT images for each Myun were close enough to those from the official statistics suggesting that the LANDSAT images can be used for the estimation of landuse status.

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Analysis of Early Revegetation Effect in Rock Slopes using Vegetation-Plant (식생플랜트를 이용한 암반비탈면의 조기녹화 효과분석)

  • Ma, Ho-Seop;Kang, Won-Seok;Park, Jin-Won
    • Journal of the Korean Society of Environmental Restoration Technology
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    • v.13 no.5
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    • pp.81-89
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    • 2010
  • This study was conducted to evaluate the effects of early revegetation by analyzing the characteristics of germination and growth of Chrysanthemum zawadskii using vegetation-plant in rock slopes. After making up a growing basis of approximately 20-cm depth and 10-cm diameter by using a boring machine, the surface of rock slopes was planted with vegetation-plant. The number of germinating populations by soil media was 41 in H.s, 4 in T.s, 3 in M.s, and 0 in M.g.s. The germination rate (%) by soil media was 20.0% in H.s, 3.3% in T.s, 2.5% in M.s and 0% in M.g.s. In monthly changes of growth rate, the aspect was northwest direction, the soil media was H.s, and the treatment was microorganism plot. The main factors affecting survivorship and growth of population were soil media and treatment plot. The interaction between each factor had a good effects in bearing x treatment plot, soil media x treatment plot. but, it is recommended that the mulching of vegetation plant is highly needed to help the germination of seed and growth of vegetation because of loss of seed and soil media occurred due to rainfall. Therefore, The result suggests that the revegetation technique using boring in rock slope was very efficient in respect of the early revegetation and the landscape.

Studies on Vegetation for Ecological Restoration of Salt Marshes in Saemangeum Reclaimed Land - Germination Strategies and Character of Halophytes - (새만금 간척지일대 염습지 생태복원을 위한 식생학적 연구 - 염생식물 발아 전략 및 특성 -)

  • Kim, Chang-Hwan
    • Journal of Environmental Science International
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    • v.18 no.4
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    • pp.451-462
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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 young sapling. From the results of laboratory analysis into dynamics of the saplings of halophyte, it was revealed that the germination ratio of the dry area and submerged area decreases in the order of Suaeda asparagoides, Suaeda japonica, Salicornia herbacea, Atriplex gmelini and Aster tripolium.

Population Changes of Moths (Insecta: Lepidoptera) from Mt. Wolchul National Park, Jeollanam-do, Korea

  • Choi, Sei-Woong;Park, Marana;Chang, Young-Hyo
    • Journal of Ecology and Environment
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    • v.30 no.3
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    • pp.245-250
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    • 2007
  • We investigated the moth fauna and monthly changes in moth populations at three sites - Dogapsa, Gyungpodae and Muwisa - in Mt. Wolchul National Park, Jeollanam-do, South Korea. From February to October, 2006, we collected a total of 1677 individuals comprising 348 species in 14 families. Monthly changes in the abundance of species and individuals showed an M-shaped pattern, with the highest peak in June and a second high peak in August. The diversity of the three dominant families (Noctuidae, Geometridae and Pyralidae) at the three sites varied, possibly due to differences in vegetation and other environmental factors. Diversity at Dogapsa was relatively higher than Gyungpodae and Muwisa, but, the fauna at Dogapsa more closely resembled Muwisa than Gyungpodae. 28 species occurred at the same time in all three sites, included the families Geometridae (14 species), Noctuidae (9 species), Pyralidae (2 species), Arctiidae (1 species), Nolidae (1 species), and Limacodidae (1 species). The present study provided baseline information about biodiversity and phenological patterns of moth abundance and permitted evaluation of moth biodiversity as a monitoring tool for vegetation structure and environmental change.

A Study on the Priority Area Selection for Updating FDB Attributes using MODIS Product (MODIS Product를 활용한 FDB 속성 갱신 대상지역 선정 연구)

  • Park, Wan-Yong;Eo, Yang-Dam;Kim, Yong-Min;Kim, Chang-Jae
    • Journal of the Korea Institute of Military Science and Technology
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    • v.16 no.1
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    • pp.65-73
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    • 2013
  • FDB(Feature DataBase) attributes have been produced by using the resource data prior to the year 2002. Due to this reason, the attributes need to be updated to the up-to-date ones. In this regards, this study focuses on the way of finding areas whose attributes need to be updated. Forest and crop classes were chosen as target classes among FDB features. MODIS Landcover data and FDB are, first, compared to detect the changed forest and crop areas from 2001 to 2008. Then, vegetation vitality changes are analyzed using MODIS annual NDVI data. Based on the change detection and the vegetation vitality analysis, the index of area selection for updating FDB attributes is proposed in this study.

Vegetation of Gangcheonsan Provincial Park in Cheollabuk-do (강천산 군립공원의 식생)

  • Kim, Ha-Song;Oh, Jang-Geun;Jun, Ji-Young
    • Korean Journal of Ecology and Environment
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    • v.46 no.1
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    • pp.25-32
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    • 2013
  • This study examined the status of the vegetation around Gangcheonsan provincial park located in Sunchang-gun in Jeollabuk-do and Damyang-gun in Jeollanam-do from June 4 to October 12, 2011. Gangcheonsan vegetation was arranged 9 plant communities in accordance with data of 28 releves. Major forest vegetation included Quercus variabilis communityand Quercus variabilis-Quercus serrata community, Pinus densiflora community, and Pinus densiflora-Quercus variabilis community (evergreen coniferous forest in all), and Phyllostachys nigra var. henonis community (plantation). Wetland vegetation included Salix gracilistyla community (riverbank forests), Phragmites japonica community, and Polygonia thunbergii community. Gangcheonsan Provincial Park has beautiful scenery that is in harmony with fantastically-shaped rocks, waterfalls, and valleys and conserves a specific plant community habitat distributed through the forest wetlands including its valleys. It is necessary to conduct long-term monitoring with its focus on Pinus densiflora community, Lycoris koreana community, and Lycoris squamigera community in the provincial park to grasp the characteristics of ecological inhabit changes in major communities and provide active methods for conservation, restoration, and publicity.

Urban Thermo-profiles and Community Structure of Quercus mongolica Forests along an Urban-rural Land Use Gradient: Implications for Management and Restoration of Urban Ecosystems

  • Cho, Yong-Chan;Cho, Hyun-Je;Lee, Chang-Seok
    • Journal of Ecology and Environment
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    • v.32 no.3
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    • pp.167-176
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    • 2009
  • Land cover changes associated with urbanization have driven climate change and pollution, which alter properties of ecosystems at local, regional, and continental scales. Thus, the relationships among urban ecological variables such as community composition, structure, health, soil and functioning need to be better understood to restore and improve urban ecosystems. In this study, we discuss urban ecosystem management and research from a futuristic perspective based on analyses of vegetation structure, composition, and successional trends, as well as the chemical properties of soils and the distribution of heat along an urban-rural gradient. Urban thermo-profile analysis using satellite images showed an obvious mitigating effect of vegetation on the Seoul heat island. Community attributes of Quercus mongolica stands reflected the effects of urbanization, such as pronounced increases in disturbance-related and pollution-tolerant species, such as Styrax japonica and Sorbus alnifolia. Retrogressive successional trends were detected in urban sites relative to those in rural sites. Changes in the urban climate and biotic environment have the potential to significantly influence the practice and outcomes of ecological management, restoration and forecasting because of the associated changes in future bio-physical settings. Thus, for management (i.e., creation and restoration) of urban green spaces, forward-thinking perspectives supported by historical information are necessary.