• Journal of Environmental Impact Assessment
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• v.25 no.3
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• pp.190-208
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• 2016

This study was carried out to understand the spatial distribution and conservation, restoration plan for vegetation in the Hwaeom wetland protected area. Total 29 phytosociological releves consisted of 117 plant species (unidentified species contained) was made during field studies conducted at 2008 and 2013 applying Braun-Branquet method. The collected vegetations were arranged 8 plant communities and thus divided hydric types (Drosera rotundifolia-Eleocharis congesta community, Carex forficula-Molinia japonica community) and xeric types (Miscanthus sinensis community, Rhododendron yedoense var. poukhanense community, Tripterygium regelii community, Carex gifuensis-Quercus mongolica community) under moisture conditions. The hydric types growing in hydric conditions distributed along hollowed out ground or the water channel that have a key qualification to protect. In the wetland protected area, the hydric vegetation types were mostly covered about 3.8% and the xeric types dominating by Miscanthus sinensis were most wildly distributed about 51.5%. Various woody plant species invaded the place. In 2008, invasion plants observed with total 14 species - 8 tree species (227 individual), 6 shrub species (51 individual) and alders (Aluns japonica) found in 2013. We suggested finding out that the sustainable conservation and management in Hwaeom wetland should be setting up plan focused on activity and variability such as continuous monitoring (changing vegetation types, spatial distribution, invasion plants) and zonation management (core zone, buffer zone, transition zone).

• Journal of Korean Society for Geospatial Information Science
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• v.21 no.4
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• pp.73-81
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• 2013

Ordinary least squares (OLS) regression is the primary statistical method in previous studies for vegetation distribution patterns in relation to landform. However, this global regression lacks the ability to uncover some local-specific relationships and spatial autocorrelation in model residuals. This study employed geographically weighted regression (GWR) to examine the spatially varying relationships between NDVI (Normalized Difference Vegetation Index) patterns and changing trends of landform (elevation, slope) and solar intensity (insolation and duration of sunshine) in Mt Geum-gang of North-Korea. Results denoted that GWR was more powerful than OLS in interpreting relationships between NDVI patterns and landform/solar intensity, since GWR was characterized by higher adjusted R2, and reduced spatial autocorrelations in model residuals. Unlike OLS regression, GWR allowed the coefficients of explanatory variables to differ by locality by giving relatively more weight to NDVI patterns which are affected by local landform and solar factors. The strength of the regression relationships in the GWR increased significantly, by showing regression coefficient of higher than 70% (0.744) in the southern ridge of the experimental area. It is anticipated that this research output will serve to increase the scientific and objective vegetation monitoring in relation to landform and solar intensity by overcoming serious constraints suffered from the past non-GWR-based approach.

• Proceedings of the KSRS Conference
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• 2003.11a
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• pp.516-518
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• 2003

This study discusses an effort to build a model to link normalized difference vegetation indices (NDVI) and socio-economic indicators derived from village survey (1990, 1993, 1996, and 2000) statistical data in Bekasi, West Java, Indonesia. Socio-economics indicators of sub-district level, in this study the number of agricultural households (AH), are aggregated from village level data. NDVI from Landsat-TM resolution data (1989 and 1997) are computed to detect land use/land cover (LULC) dynamics in the sub-district areas. Attention is mainly paid on the examination of agricultural land cover changing in the sub-district level. NDVI measurements might be used to predict AH dynamics as showed by computed linear regression models.

• Korean Journal of Environment and Ecology
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• v.37 no.1
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• pp.13-34
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• 2023

Many ecologists try to understand plant communities and societies' changing processes by interacting with environmental factors. Plant communities formed in the sidings of streams, which are more dynamic than forest vegetation, are closely related to the disturbance regime of streams. U. pumila, which forms communities at the edges of streams, is distributed over the central and northern regions of the Korean Peninsula. In this study, we intended to explain the regeneration of U. pumila communities in the upstream region of the Namhangang River. Heights from the stream surface to the mid-high points of communities increased when the age class of U. pumila communities increased. On the other hand, the height of U. pumila tended to increase and decrease as the age class increased. The richness (S), evenness (J'), diversity (H'), and maximum diversity (H'max) also showed a tendency to increase and then decrease as the age class increased. On the other hand, the number of stems per individual and density (D) decreased as the age class increased. Seedlings of U. pumila failed to regenerate in the communities at the intermediate or higher stage of the age class. Regeneration of seedlings occurred in the spaces formed by the flooding, which occurred periodically in streams. After regeneration, U. pumila communities grew like a single organism. On the other hand, the plant species consisting of U. pumila communities exhibited a process in which the S and H' increased and then decreased as they developed. In other words, we determined that the changes in the species compositions were associated with changes in each species' environment and community. A space where seeds can regenerate seedlings should be provided for the regeneration of U. pumila communities. In the mid/upstream region of the Namhangang River, where the present study focused, newly formed communities were rare because the space required to regenerate U. pumila ceased to exist. Accordingly, we suggest securing an appropriate space for the regeneration of seedlings to maintain the U. pumila communities in the upstream region of the Namhangang River.

• Journal of Ecology and Environment
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• v.48 no.1
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• pp.85-95
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• 2024

Background: In Korea, riparian zones and some floodplains have been converted into agricultural fields and urban areas. However, there are essential for maintaining biodiversity, as they are important ecological spaces. There are also very important spaces for humanity, as they perform various ecosystem services in a changing environment including climate change. Due to the importance of rivers, river restoration projects have been promoted for a long time, but their achievement has been insignificant. Development should be pursued by thoroughly evaluating the success of the restoration project. Ecological restoration is to accelerate succession, a process that a disturbed ecosystem recovers itself, with human assistance. Ecological restoration can be a test bed for testing ecological theories in the field. In this respect, ecological restoration should go beyond a 'simple landscaping exercise' and apply ecological models and theories in restoration practice. Results: The cross-section of the restored stream is far from natural rivers due to its steep slope and artificial material. The vegetation profiles of the restored streams did not reflect the flooding regime of the river. The species composition of the vegetation in the restored stream showed a significant difference from that of the reference stream, and was also different from that of an unrestored urban stream. Although species richness was high and the proportion of exotic species was low in the restored stream, the effect was offset by the high proportion of gardening and landscaping plants or obligate terrestrial plants. Conclusions: Based on both the morphological and ecological characteristics of the river, the restoration effect in the restored stream was evaluated to be very low. In order to solve the problems, a systematic adaptive management plan is urgently required. Furthermore, it is necessary to institutionalize the evaluation of restoration effects for the development of river restoration projects in the future.

• Journal of Ecology and Environment
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• v.34 no.2
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• pp.149-156
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• 2011

Phenological variables derived from remote sensing are useful in determining the seasonal cycles of ecosystems in a changing climate. Satellite remote sensing imagery is useful for the spatial continuous monitoring of vegetation phenology across broad regions; however, its applications are substantially constrained by atmospheric disturbances such as clouds, dusts, and aerosols. By way of contrast, a tower-based ground remote sensing approach at the canopy level can provide continuous information on canopy phenology at finer spatial and temporal scales, regardless of atmospheric conditions. In this study, a tower-based ground remote sensing system, called the "Phenological Eyes Network (PEN)", which was installed at the Gwangneung Deciduous KoFlux (GDK) flux tower site in Korea was introduced, and daily phenological progressions at the canopy level were assessed using ratios of red, green, and blue (RGB) spectral reflectances obtained by the PEN system. The PEN system at the GDK site consists of an automatic-capturing digital fisheye camera and a hemi-spherical spectroradiometer, and monitors stand canopy phenology on an hourly basis. RGB data analyses conducted between late March and early December in 2009 revealed that the 2G_RB (i.e., 2G - R - B) index was lower than the G/R (i.e., G divided by R) index during the off-growing season, owing to the effects of surface reflectance, including soil and snow effects. The results of comparisons between the daily PEN-obtained RGB ratios and daily moderate-resolution imaging spectroradiometer (MODIS)-driven vegetation indices demonstrate that ground remote sensing data, including the PEN data, can help to improve cloud-contaminated satellite remote sensing imagery.

• Journal of Korean Society of Forest Science
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• v.12 no.1
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• pp.13-21
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• 1971

As one part of the ecological studies of Korean white pine plantation, a synecological survey was made on the undergrowth vegetation of Korean white pine plantations of different age class i.e., 5, 15, 25, 35, and 40 year age classes under which shrub and ground vegetation were distinctly different. And, the results are summarized as follows. 1. In shrub, the important species is Corylus heterophylla var. japonica and the dominant species in each age-class stand are as follows; 5 year-class ; Quercus mongolica, Lespedeza Maximowiczi. 15 year-class ; Corylus heterophylla var. japonica, Lespedeza Maximowiczi. 25 year-class ; Corylus heterophylla var. japonica. 35 year-class ; Corylus heterophylla var. japonica, Maackia amurensis. 40 year-class ; Corylus heterophylla var. japonica. 2. The higher the age class of the plantation are, the lower the height and the density of the shrub become. 3. Dominant species of ground-vegetation under the shrub of each age-class are as follows; 5 year-class ; Arundinella hirta var. cilia, Miscanthus purpurascens. 15 year-class ; Arundinella hirta var. ciliata, Potentilla Freyniana. 25 year-class ; Physematium manchuriense, Viola xanthopetala, Rubus craegifolius. 35 year-class ; Viola xanthopetala, Rubus crataegifolius. 45 year-class ; Viola xanthopetala, Rubus crataegifolius. 4. The standing crops of ground vegetation under the shrub were decreased with increasing age-class, which also caused the decreasing height and density and changing floristic composition of the shrub. 5. The ratio of the standing crop of root to the standing crop of shoot was increased as the age class increased. 6. The floristic composition of ground vegetation has shown a change from heliophyte to sciophytes on the sere.

• The Korean Journal of Ecology
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• v.26 no.5
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• pp.281-287
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• 2003

We present the first analysis of moor vegetation on the Moojechi of Ulsan including syntaxonomy and syndynamics. We classified plant communities according to the Braun-Blanquet approach. In order to better understand ecological alteration processes and changing species compositions along successional gradients we also examined synecological differences using Principal Coordinate Analysis(PCoA) in terms of moisture gradient, species richness, and community structure. Classification resulted in one association and five plant communities occupying distinct moor habitats: Hypericum laxum-Eleocharis acicularis for. longiseta community, Drosera rotundifolia-Eleocharis congesta community, Platanthero-Molinietum japonicae ass. nova hoc loco, Molinia japonica-Alnus japonica community, Miscanthus sinensis-Pinus densiflora community, and Convallaria keiskei-Quercus serrata community. Due to synecological correspondences and floristic similarities in supraregional perspective, Platanthero-Molinietum can be assigned to existing higher syntaxonomic units of Molinion and Molinietalia in Braun-Blanquet system, established in Japan. We propose to extend their range and designate the new class Molinietea japonicae representative to the intermediate moor (Zwischenmoor) vegetation in Northeast Asia. PCoA resulted in four types showing a sequencess of succession: Needle spike-rush type, moor-grass type (incl. alder forest type), eulalia type, and oak forest type. A combination of edaphic conditions (soil eutrphication and soil moisture) and hydrologic patterns of moor ecosystem related to topography, occurring as result of external geophysical forces, controls inter alia spatial patterns and floristic compositions of moor plant communities.

• Korean Journal of Remote Sensing
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• v.36 no.5_2
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• pp.975-988
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• 2020

Change detection is the process of identifying changes by observing the multi-temporal images at different times, and it is an important technique in remote sensing using satellite images. Among the change detection methods, the unsupervised change detection technique has the advantage of extracting rapidly the change area as a binary image. However, it is difficult to understand the changing pattern of land cover in binary images. This study used grid points generated from seamless digital map to evaluate the satellite image change detection results. The land cover change results were extracted using multi-temporal KOMPSAT-3A (K3A) data taken by Gimje Free Trade Zone and change detection algorithm used Spectral Angle Mapper (SAM). Change detection results were presented as binary images using the methods Otsu, Kittler, Kapur, and Tsai among the automated threshold selection algorithms. To consider the seasonal change of vegetation in the change detection process, we used the threshold of Differenced Normalized Difference Vegetation Index (dNDVI) through the probability density function. The experimental results showed the accuracy of the Otsu and Kapur was the highest at 58.16%, and the accuracy improved to 85.47% when the seasonal effects were removed through dNDVI. The algorithm generated based on this research is considered to be an effective method for accuracy assessment and identifying changes pattern when applied to unsupervised change detection.

• Korean Journal of Environment and Ecology
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• v.32 no.3
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• pp.313-322
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• 2018

To investigate the changing patterns of sub-alpine forest vegetation due to climate change requires accumulation of contiguous reference data and continuous monitoring. Furthermore, it is crucial to monitor short-term ecological change of lower level vegetation to understand the trend of long-term vegetation change. Therefore, this study carried out a vegetation survey and tree diameter measurement in 36 plots of Mt. Jiri inhabited by Abies koreana species from 2015 to 2017 to examine the short-term dynamics of Abies koreana seedling and the change of vegetation distribution according to altitude. We analyzed the importance value and MIV (mean importance value) of major species by each stratum as well as the importance value and species diversity index of major species and the change of seedling population by altitude. The results showed that Abies koreana had the highest importance value on tree layer, Rhododendron schlippenbachii on shrub layer and Tripterygium regelii on herb layer. MIV was high in the order of Abies koreana, Rhododendron schlippenbachii and Acer pseudosieboldianum. Regarding the species composition and species diversity index (H') along the altitudinal gradient, Sasa borealis showed high MI and low H' in the elevation less than 1,500 m, and IV of Tripterygium regelii and H' of herb layer were high in the elevation of 1,700 - 1,800 m. Abies koreana seedling decreased by 22.4% from 1,250 n/ha in 2015 to 970 n/ha in 2017 (p <0.05) throughout the investigated area. The decline rate along seedling and sapling height were 22.9% in less than 10 cm, 3.4% in 10-30 cm, 8.9% in 30-50 cm, 39.3% in 50-100 cm, and 55.1% more than 100 cm. Few of A. koreana seedlings appeared due to the dominance of Sasa borealis in the elevation of 1,500 m or less and due to the dominance and high species diversity of Tripterygium regelii in the elevation of 1,700-1,800 m. On the other hand, many of A. koreana seedlings appeared in the elevation of 1,600-1,700 m due to no distribution of S. borealis and T. regelii species in that altitude range. Therefore, we concluded that those seedlings and saplings of A. koreana could be more stable in the altitude of 1,600-1,700 m.