• Title/Summary/Keyword: Vegetation

Search Result 4,618, Processing Time 0.102 seconds

Multicriterion Matrix Technique of Vegetation Assessment - A New Evaluation Technique on the Vegetation Naturalness and Its Application - (다항목 매트릭스 식생평가 기법 식생의 자연성 평가에 대한 새로운 기법과 그 적용 -)

  • 김종원;이은진
    • The Korean Journal of Ecology
    • /
    • v.20 no.5
    • /
    • pp.303-313
    • /
    • 1997
  • A new evaluation technique, i.e. multicriterion matrix technique, on the vegetation assessment was proposed and compared with several techniques having been previously used in the environmental impact assessment. Four criterias and 10 subcriterias were selected for two evaluation indices such as vegetation naturalness value and vegetation class. These criterias were characterized by syntaxonomical informations of hemeroby concept and potential vegetation, hierarchical system between criterias, and ordinal scale of vegetation naturalness valuse. Vegetation naturalness values were classified into 11 ordinal levels and condensed to five vegetation classes for facilitating practical use. In the example study two sites were compared by using two indices. This technique could have useful applications for ssessment of regional vegetation. A vegetation map of naturalness described by combination of two indices was proposed in order to illustrate regional vegetation naturalness.

  • PDF

Multi-temporal analysis of vegetation indices for characterizing vegetation dynamics

  • Javzandulam, Tsend-Ayush;Tateishi, Ryutaro;Kim, Dong-Hee
    • Proceedings of the KSRS Conference
    • /
    • 2003.11a
    • /
    • pp.405-407
    • /
    • 2003
  • An attempt has been in this study to delineate the characteristics of spectral signatures of the vegetation in terms of various VIs, particularly made the Normalized Difference Vegetation Index(NDVI), Modified Soil Adjusted Vegetation Index2(MSAVI2) and Enhanced Vegetation Index(EVI). Multitemporal SPOT-4 VEGETATION data from 1998 to 2002 have been used for the analysis. They have been compared with each other for their similarities and differences. The correlations between the vegetation indices observed at various degree of vegetation coverage during their different stages of growth were examined. All of the VIs have shown qualitative relationships to variations in vegetation. Apparently, the NDVI and MSAVI2 are highly correlated for all of the temporal changes, representing the different stages of phenology.

  • PDF

Influences of Urban Trees on the Control of the Temperature (도시의 수목이 기온의 조절에 미치는 영향)

  • 김수봉;김해동
    • Journal of the Korean Institute of Landscape Architecture
    • /
    • v.30 no.3
    • /
    • pp.25-34
    • /
    • 2002
  • The purpose of this paper is to discuss the function of microclimate amelioration of urban trees regarding the environmental benefits of street trees in summer, focusing on the heat pollution-urban heat island, tropical climate day's phenomenon and air pollution. We measured the diurnal variation of air/ground temperatures and humidity within the vegetation canopy with the meteorological tower observation system. Summertime air temperatures within the vegetation canopy layer were 1-2$^{\circ}C$ cooler than in places with no vegetation. Due to lack of evaporation, the ground surface temperatures of footpaths were, at a midafternoon maximum, 8$^{\circ}C$ hotter than those under trees. This means that heat flows from a place with no vegetation to a vegetation canopy layer during the daytime. The heat is consumed as a evaporation latent heat. These results suggest that the extension of vegetation canopy bring about a more pleasant urban climate. Diurnal variation of air/ground temperatures and humidity within the vegetation canopy were measured with the meteorological tower observation system. According to the findings, summertime air temperatures under a vegetation canopy layer were 1-2$^{\circ}C$ cooler than places with no vegetation. Due mainly to lack of evaporation the ground surface temperature of footpaths were up to 8$^{\circ}C$ hotter than under trees during mid-afternoon. This means that heat flows from a place where there is no vegetation to another place where there is a vegetation canopy layer during the daytime. Through the energy redistribution analysis, we ascertain that the major part of solar radiation reaching the vegetation cover is consumed as a evaporation latent heat. This result suggests that the expansion of vegetation cover creates a more pleasant urban climate through the cooling effect in summer. Vegetation plays an important role because of its special properties with energy balance. Depended on their evapotranspiration, vegetation cover and water surfaces diminish the peaks of temperature during the day. The skill to make the best use of the vegetation effect in urban areas is a very important planning device to optimize urban climate. Numerical simulation study to examine the vegetation effects on urban climate will be published in our next research paper.

Development of a Fusion Vegetation Index Using Full-PolSAR and Multispectral Data

  • Kim, Yong-Hyun;Oh, Jae-Hong;Kim, Yong-Il
    • Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
    • /
    • v.33 no.6
    • /
    • pp.547-555
    • /
    • 2015
  • The vegetation index is a crucial parameter in many biophysical studies of vegetation, and is also a valuable content in ecological processes researching. The OVIs (Optical Vegetation Index) that of using multispectral and hyperspectral data have been widely investigated in the literature, while the RVI (Radar Vegetation Index) that of considering volume scattering measurement has been paid relatively little attention. Also, there was only some efforts have been put to fuse the OVI with the RVI as an integrated vegetation index. To address this issue, this paper presents a novel FVI (Fusion Vegetation Index) that uses multispectral and full-PolSAR (Polarimetric Synthetic Aperture Radar) data. By fusing a NDVI (Normalized Difference Vegetation Index) of RapidEye and an RVI of C-band Radarsat-2, we demonstrated that the proposed FVI has higher separability in different vegetation types than only with OVI and RVI. Also, the experimental results show that the proposed index not only has information on the vegetation greenness of the NDVI, but also has information on the canopy structure of the RVI. Based on this preliminary result, since the vegetation monitoring is more detailed, it could be possible in various application fields; this synergistic FVI will be further developed in the future.

Actual Vegetation Potential Natural Vegetation of Pukhansan National Park, Mid-western Korea (북한산국립공원의 현존식생과 잠재자연식생)

  • 이은복
    • The Korean Journal of Ecology
    • /
    • v.20 no.6
    • /
    • pp.439-450
    • /
    • 1997
  • The potential natural vegtation of the Pukhansan National Park area, mid-western Korea, was inferred from the actual vegetation. With the phytosociological classification and field surveys, the actual vegetation map of the park area was made on a scale of 1:25, 000, including fourteen communities. By the analyses of the species diversity, the age structure, the human interferences and various informations on vegetation changes, two pathways of late stage succession from Pinus densiflora forests to the climatic climax were suggested. One is from Quercus serrata forests to Q. mongolica forests throughout the mountain and the other, from Q. variabilis or Q. acutissima forests to Carpinus laxiflora forests in lower parts. Considering the vegetation changes, the potential natural vegetation of the park area mainly composed of Q. mongolica, C. laxiflora, P. densiflora and Zelkova serrata forest as the climatic and/or edaphic climax was inferred.

  • PDF

On the Thermal Effect of Vegetation Canopy to the Surface Sublayer Environment Part 1 : Numerical Experiment (Vegetation Canopy의 접지층 환경에 대한 열적 영향 제1부 : 수치실험)

  • 진병화;황수진
    • Journal of Environmental Science International
    • /
    • v.8 no.2
    • /
    • pp.145-150
    • /
    • 1999
  • To estimate the thermal effect of the vegetation canopy on the surface sublayer environment numerically, we used the combined model of Pielke's1) single layer model for vegetation and Deardorff's2) Force restore method(FRM) for soil layer. Application of present combined model to three surface conditions, ie., unsaturated bare soil, saturated bare soil and saturated vegetation canopy, showed followings; The diurnal temperature range of saturated vegetation canopy is only 20K, while saturated bare soil and unsaturated bare soil surface are 30K, 35K, respectively. The maximum temperature of vegetation canopy occurs at noon, about 2 hours earlier than that of the non-vegetation cases. The peak latent heat fluxes of vegetation canopy is simulated as a 600Wm-2 at 1300 LST. They have higher values during afternoon than beforenoon. Furthermore, the energy redistribution ratios to latent heat fluxes also increased in the late afternoon. Therefore, oasis effect driving from the vegetation canopy is reinforced during late afternoon compared with the non-vegetated conditions.

  • PDF

Study on Forest Vegetation Classification with Remote Sensing

  • Yuan, Jinguo;Long, Limin
    • Proceedings of the KSRS Conference
    • /
    • 2002.10a
    • /
    • pp.250-255
    • /
    • 2002
  • This paper describes the study methods of identifying forest vegetation types, based on this study, forest vegetation classification method based on vegetation index is proposed. According to reflectance data of vegetation canopy and soil line equation NIR=1.506R+0.0076 in Jingyuetan, Changchun, China, many vegetation index are calculated and analyzed. The relationships between vegetation index and vegetation types are that PVI identifies broadleaf forest and conifer forest the most easily, the next is TSAVI and MSAVI, but their calculation is complex. RVI values of different conifer trees vary obviously, so RVI can classify conifer trees. In a word, combination of PVI and RVI is evaluated to classify different vegetation types.

  • PDF

Global Warming and Alpine Vegetation

  • Kong, Woo-seok
    • The Korean Journal of Ecology
    • /
    • v.22 no.6
    • /
    • pp.363-369
    • /
    • 1999
  • Reconstruction of the past vegetational changes of Korea in connection with climate changes enables to understand the impacts of past and future global warming on alpine vegetation. Despite the early appearance of the cold-tolerant vegetation since the Mesozoic Era. the occurrence of warmth-tolerant vegetation during the Oligocene and Miocene implies that most of alpine and subalpine vegetations have been confined to the alpine and subalpine belts of northern Korean Peninsula. The presence of cold-episodes during the Pleistocene. however. might have caused a general southward and downslope expansions of cold-tolerant alpine and subalpine vegetation. But the climatic warming trend during the Holocene or post-glacial period eventually has isolated cold-tolerant alpine and subalpine vegetation mainly in the northern Korea. but also on scattered high mountains in the southern Korea. The presence of numerous arctic-alpine and alpine plants on the alpine and subalpine belts is mainly due to their relative degree of sensitivity to high summer temperatures. Global warming would cause important changes in species composition and altitudinal distributional pattern. The altitudinal migration of temperate vegetation upward caused by climatic warming would eventually devastate alpine plants.

  • PDF

Drone-based Vegetation Index Analysis Considering Vegetation Vitality (식생 활력도를 고려한 드론 기반의 식생지수 분석)

  • CHO, Sang-Ho;LEE, Geun-Sang;HWANG, Jee-Wook
    • Journal of the Korean Association of Geographic Information Studies
    • /
    • v.23 no.2
    • /
    • pp.21-35
    • /
    • 2020
  • Vegetation information is a very important factor used in various fields such as urban planning, landscaping, water resources, and the environment. Vegetation varies according to canopy density or chlorophyll content, but vegetation vitality is not considered when classifying vegetation areas in previous studies. In this study, in order to satisfy various applied studies, a study was conducted to set a threshold value of vegetation index considering vegetation vitality. First, an eBee fixed-wing drone was equipped with a multi-spectral camera to construct optical and near-infrared orthomosaic images. Then, GIS calculation was performed for each orthomosaic image to calculate the NDVI, GNDVI, SAVI, and MSAVI vegetation index. In addition, the vegetation position of the target site was investigated through VRS survey, and the accuracy of each vegetation index was evaluated using vegetation vitality. As a result, the scenario in which the vegetation vitality point was selected as the vegetation area was higher in the classification accuracy of the vegetation index than the scenario in which the vegetation vitality point was slightly insufficient. In addition, the Kappa coefficient for each vegetation index calculated by overlapping with each site survey point was used to select the best threshold value of vegetation index for classifying vegetation by scenario. Therefore, the evaluation of vegetation index accuracy considering the vegetation vitality suggested in this study is expected to provide useful information for decision-making support in various business fields such as city planning in the future.

The effect of vegetation parameter characteristics of the multi-layer vegetation model on wind for numerical simulation of micro-meteorology (미기상 수치모의를 위한 다층식생모델의 식생 팍라메타가 바람에 미치는 영향)

  • 오은주;이화운;정용현
    • Journal of Environmental Science International
    • /
    • v.12 no.6
    • /
    • pp.605-613
    • /
    • 2003
  • In order to make use of the protection effect against wind by the vegetation, it examined whether it should make what vegetation form and arrangement using the 2-dimensional non-hydrostatic model. When the foliage shielding factor increases, it becomes hard to take in protection effect against wind in a residential section. When it makes height of vegetation high, it becomes hard to take in protection effect against wind with height. In the comparison in the case where vegetation high is gradually made low toward wind-stream from a vegetation, and the case of making it low gradually, although former tends to receive the protection effect against wind by the vegetation, attenuation of wind velicity becomes large. In the comparison in the case where foliage shielding factor and distribution of density of leaf are gathered gradually toward wind-stream from a vegetation. It has been understood to evaluate to height the influence that the vegetation multi-layer model by which the heat revenue and expenditure in the direction of the vegetation height is considered is used, and to characterize the vegetation group by the parameter setting.