• Proceedings of the KSRS Conference
• /
• 2008.10a
• /
• pp.151-154
• /
• 2008

Information on the area and spatial distribution of crop fields is needed for biomass production, arrangement of water resources, trace gas emission estimates, and food security. The present study aims to monitor crops status during the growing season by estimating its aboveground biomass and leaf area index (LAI) from field reflectance taken with a hand-held radiometer. Field reflectance values were collected over specific spectral bandwidths using a handheld radiometer(LI-1800). A methodology is described to use spectral reflectance as indicators of the vegetative status in crop cultures. Two vegetation indices were derived from these spectral measurements. In this paper, first we analyze each spectral reflectance characteristics of vegetation in the order of growth stage. Vegetation indices (NDVI, GNDVI) were calculated from crop reflectance. And assess the nature of relationships between LAI and VI, as measured by the in situ NDVI and GNDVI. Among the two VI, NDVI showed predictive ability across a wider range of LAI than did GNDVI. Specific objectives were to determine the relative accuracy of these two vegetation indices for predicting LAI. The results of this study indicated that the NDVI and GNDVI could potentially be applied to monitor crop agriculture on a timely and frequent basis.

• Korean Journal of Plant Resources
• /
• v.20 no.6
• /
• pp.540-543
• /
• 2007

We have investigated the vegetation in the peninsula located in Ongjeong-Li Seomyeon in Youngweol-gun. Since this is a limestone area, boxtrees, Abelia mosanensis T. H. Chung ex Nakai, and Selaginella stauntoniana Spring were abundant, as these are types of vegetation characteristic of limestone areas. Pinus densiflora S. et Z. was the most dominant woody plant, but vegetational changes, such as the dominance of Quercus variabilis Blume, Quercus dentata Thunb, and Quercus mongolica Fischer, were observed in spots. In particular, the growth of nursery plants of pinus densiflora S. et Z. was not observed, and young trees like Quercus mongolica Fischer grow as low vegetation of Pinus densiflora S. et Z.. Thus, the ecological succession of Quercus mongolica Fischer is predicted. Outside the investigation area, as herbaceous plants, various vegetations were observed, including Selaginella stauntoniana Spring, Thalictrum coreanum H. Lev., Mukdenia rossii(Oliv.) Koidz., Platanthera freynii Kraenzl., Cephalanthera longibracteata Blume, Potentilla dickinsii Franch., Patrinia rupestris(Pall.) Juss., Swertia pseudochinensis H. Hara, Vicia venosa(Willd.) Maxim., Pyrola japonica Klenze ex Alef., Disporum smilacinum A. Gray, Artemisia stolonifera(Maxim.) Kom. for. Stolonifera, Smilax nipponica Miq., Adenophora triphylla var. japonica(Regel) H. Hara, Isodon inflexus(Thunb.) Kudo, Gentiana scabra Bunge for. Scabra, Polygonatum odoratum var. pluriflorum(Miq.) Ohwi, Dioscorea quinqueloba Thunb., Syneilesis palmata(Thunb.) Maxim., Asparagus schoberioides Kunth, Eupatorium japonicum Thunb. ex Murray, Galium kinuta Nakai & Hara, Saxifraga fortunei var. incisolobata, Lilium amabile Palib., Siberian iris, Dictamnus dasycarpus Turcz., Atractylodes ovata(Thunb.) DC., and Lysimachia clethroides Duby.

• Architectural research
• /
• v.25 no.4
• /
• pp.73-84
• /
• 2023

Indoor thermal conditions greatly affect the health and comfort of humans who occupy the space in it. The purpose of this research is to analyze the influence of water and vegetation elements as a microclimate modifier in buildings to obtain thermal comfort through the study of thermal environment models. This research covers two objects, namely public buildings and housing in Makassar City, South Sulawesi Prov-ince - Indonesia. Quantitative methods through field surveys and measurements based on thermal and personal variables. Data analysis based on ASHRAE 55 2020 standard. The data was processed with a parametric statistical approach and then simulated with the Computational Fluid Dynamics (CFD) simulation method to find a thermal prediction model. The model was made by increasing the ventilation area by 2.0 m2, adding 10% vegetation with shade plant characteristics, moving water features in the form of fountains and increasing the pool area by 15% to obtain PMV + 0.23, PPD + 8%, TSV-1 - +0, Ta_25.7℃, and relative humidity 63.5 - 66%. The evaluation shows that the operating temperature can analyze the visitor's comfort temperature range of >80% and comply with the ASHRAE 55-2020 standard. It is concluded that water elements and indoor vegetation can be microclimate modifiers in buildings to create desired comfort conditions and adaptive con-trols in buildings such as the arrangement of water elements and vegetation and ventilation systems to provide passive cooling effects in buildings.

• Journal of Korean Society of Rural Planning
• /
• v.30 no.1
• /
• pp.57-66
• /
• 2024

This study aimed to develop a precise vegetation cover classification model for small streams using the combination of drone remote sensing and support vector machine (SVM) techniques. The chosen study area was the Idong stream, nestled within Geosan-gun, Chunbuk, South Korea. The initial stage involved image acquisition through a fixed-wing drone named ebee. This drone carried two sensors: the S.O.D.A visible camera for capturing detailed visuals and the Sequoia+ multispectral sensor for gathering rich spectral data. The survey meticulously captured the stream's features on August 18, 2023. Leveraging the multispectral images, a range of vegetation indices were calculated. These included the widely used normalized difference vegetation index (NDVI), the soil-adjusted vegetation index (SAVI) that factors in soil background, and the normalized difference water index (NDWI) for identifying water bodies. The third stage saw the development of an SVM model based on the calculated vegetation indices. The RBF kernel was chosen as the SVM algorithm, and optimal values for the cost (C) and gamma hyperparameters were determined. The results are as follows: (a) High-Resolution Imaging: The drone-based image acquisition delivered results, providing high-resolution images (1 cm/pixel) of the Idong stream. These detailed visuals effectively captured the stream's morphology, including its width, variations in the streambed, and the intricate vegetation cover patterns adorning the stream banks and bed. (b) Vegetation Insights through Indices: The calculated vegetation indices revealed distinct spatial patterns in vegetation cover and moisture content. NDVI emerged as the strongest indicator of vegetation cover, while SAVI and NDWI provided insights into moisture variations. (c) Accurate Classification with SVM: The SVM model, fueled by the combination of NDVI, SAVI, and NDWI, achieved an outstanding accuracy of 0.903, which was calculated based on the confusion matrix. This performance translated to precise classification of vegetation, soil, and water within the stream area. The study's findings demonstrate the effectiveness of drone remote sensing and SVM techniques in developing accurate vegetation cover classification models for small streams. These models hold immense potential for various applications, including stream monitoring, informed management practices, and effective stream restoration efforts. By incorporating images and additional details about the specific drone and sensors technology, we can gain a deeper understanding of small streams and develop effective strategies for stream protection and management.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.26 no.6
• /
• pp.135-154
• /
• 2023

Urban wetlands provide various ecosystem services and are subject to restoration and creation projects due to their increased value in the context of climate change. However, the vegetation structure of wetlands is sensitive to environmental changes, including artificial disturbances, and requires continuous maintenance. In this study, we conducted a vegetation survey of three wetlands created as part of a project to restore urban degraded natural ecosystems and monitored the quantitative changes in wetland vegetation structure using an unmanned aerial vehicle. The vegetation survey revealed 73 species in Incheon Yeonhui wetland, and the change in vegetation composition based on wetland occurrence frequency was 11.5% on average compared to the 2018 vegetation survey results. The vegetation survey identified 44 species in Busan Igidae wetland, and the proportion of species classified as obligate upland plants was the highest at 48.8% among all plants, while the proportion of naturalized plants accounted for 15.9% of all plants. The open water surface area decreased from 10% in May 2019 to 6.7% in May 2020. Iksan Sorasan wetland was surveyed and 44 species were confirmed, and it was found that the proportion of facultative wetland plant decreased compared to the 2018 vegetation survey results, and the open water surface area increased from 0.4% in May 2019 to 4.1% in May 2020. The results of this study showed that wetlands with low artificial management intensity exhibited a tendency for stabilization of vegetation structure, with a decrease in the proportion of plants with high wetland occurrence frequency and a relatively small number of new species. Wetlands with high artificial management intensity required specific management, as they had a large change in vegetation structure and a partially high possibility of new invasion. We reaffirmed the importance of continuous monitoring of vegetation communities and infrastructure for wetlands considering the function and use of urban wetlands, and restoration stages. These research results suggest the need to establish a sustainable wetland maintenance system through the establishment of long-term maintenance goals and monitoring methods that consider the environmental conditions and vegetation composition of wetlands.

• The Korean Journal of Ecology
• /
• v.19 no.5
• /
• pp.431-451
• /
• 1996

The present studwas undertaken to classify and describe the riverside vegetation around Hanchon (36°27’-36°51’N, 128°15’-128°37’E), a tributary in the upper stream area of Nak-tong River, South Korea by methods of the ZM school of phytosociology. As a result the vegetation was divided into twenty three associations and communities belonging to ten classes. Reflecting various human impacts in the past, the associations and communities of the Artemisietea principis were most plentiful there. The vegetation units obtained in the present study were as follows: A. forest vegetation A-1 Fagetea crenatae:Zelkova serrata community, Larix leptolepis community; B. Shrub vegetation B-1 Salicetea sachalinensis:Salicetum gracilistylae, Salicetum graciliglandis assoc. nov., B-2 Rosetea sachalinensis:Salicetum gracilistylae, Salicetum graciliglandis assoc. nov., B-2 Rosetea multiflorae:Stephanandra incisa community, Lycium chinense community; C. Grassland vegetation C-1 Lemnetea minoris:Spirodela polyrhiza-Lemna paucicostata community, C-2 Bidentetea tripartiti:Polygonetum thunbergii, Polygonetum sieboldii-hydropiperis, Panico Polygonetum hydropiperis, Pharagmitetea :Oenantho- Phalaridetum arundinaceae, Phragmitetum japonicae, Miscanthetum sacchariflori, Phragmites australis community, C-4 Artemisietea principis:Artemisia princeps community, Impatiens textori community, Lactuco indicae-Humuletum japonicae, Pueraria lobata-Humulus japonicus community, Pennisetum alopecuroides community, C-5 chenopodietea:Echinochloa crus-galli var. orizicola community, Digitaria adsecendens community, Polygonum nodosum community, C-6 Miscanthetea sinensis: Miscanthus sinensis community, C-7 Plantaginetea:Eragrotis multicaulis-Plantago asiatica community. It is inferred that the endemic vegetation units in the riverside vegetation of Korea are very rare, because most of the vegetation units obtained in the present study are common with those of Japan. Among the above vegetation units, the Salicetum graciliglandis was established as a new association. On the other hand, the associations and communities of classes characterizing the riverside vegetation increased with a decrease of human impacts from the downstream to the upstream in Hanchon, while the number of the naturalized plants was the reverse. Also based on the present phytosociological work, the relation between the vegetation units and their environmental conditions and the restoration ecology and nature conservation of the riverside vegetation were discussed here in detail.

• Korean Journal of Remote Sensing
• /
• v.40 no.1
• /
• pp.9-18
• /
• 2024

Small streams, despite their rich ecosystems, face challenges in vegetation assessment due to the limitations of traditional, time-consuming methods. This study presents a groundbreaking approach, combining unmanned aerial vehicles(UAVs), convolutional neural networks(CNNs), and the vegetation differential vegetation index (VDVI), to revolutionize both assessment and management of stream vegetation. Focusing on Idong Stream in South Korea (2.7 km long, 2.34 km² basin area)with eight diverse revetment methods, we leveraged high-resolution RGB images captured by UAVs across five dates (July-December). These images trained a ResNeXt101 CNN model, achieving an impressive 89% accuracy in classifying vegetation cover(soil,water, and vegetation). This enabled detailed spatial and temporal analysis of vegetation distribution. Further, VDVI calculations on classified vegetation areas allowed assessment of vegetation vitality. Our key findings showcase the power of this approach:(a) TheCNN model generated highly accurate cover maps, facilitating precise monitoring of vegetation changes overtime and space. (b) August displayed the highest average VDVI(0.24), indicating peak vegetation growth crucial for stabilizing streambanks and resisting flow. (c) Different revetment methods impacted vegetation vitality. Fieldstone sections exhibited initial high vitality followed by decline due to leaf browning. Block-type sections and the control group showed a gradual decline after peak growth. Interestingly, the "H environment block" exhibited minimal change, suggesting potential benefits for specific ecological functions.(d) Despite initial differences, all sections converged in vegetation distribution trends after 15 years due to the influence of surrounding vegetation. This study demonstrates the immense potential of UAV-based remote sensing and CNNs for revolutionizing small-stream vegetation assessment and management. By providing high-resolution, temporally detailed data, this approach offers distinct advantages over traditional methods, ultimately benefiting both the environment and surrounding communities through informed decision-making for improved stream health and ecological conservation.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.21 no.4
• /
• pp.83-99
• /
• 1994

To compare basic information and to inspect impacts situations between 1987 and 1992, this study was executed in Chongnung valley of Mt. Puk'an. And to provide basic informations through the change of plant species diversity, some methods were applied and analyzed such as the degree of environmental impacts and belt-transect method. The results were summarized as follows; 1. In order to find environmental impacts by visitor, the degree of environmental impacts class that was proposed by Kwon(1991) was implicated. In 4 sites, total area of over impact class 2 is 86,692$m^2$ and area of impacts class 4-6 that is impossible to recover naturally is 36,856$m^2$. Totally, the impacted area was profounded qualitatively and quantitatively against 1987's. 2. In the vegetation change by visitor's impacts, species diversity was rapidly decreased as nearer the campsite and trail. And in the basal area and coverage, lower layer species was sensitively changed. Trampling-resistent species is as following; Robinia pseudoacacia, Lespedeza cyrtobotrya, Staphylea bumalda, Clerdendron trichotomum, Stephanandra incisa, Rubus crataegifolius, Lespedeza maximowiczii, Weigela subsessilis, Rosa multiflora, Zanthoxylum schinifolium, Lindera obtusiloba, Callicarpa japonica, Sorbus alnifolia, Symplocos mongolica and so on. In the results of soil hardness test, that was decreased as far away from campsite and trail. 3. In the 4 sites selected in Chongnung valley of Puk'ansan Natioal Park, management plans was largely divided 4 category, such as trail improvement, facilities setting, ecotone vegetation establishment, and vegetation rehabilitation. And a suggestion was provided to each site.

• Korean Journal of Remote Sensing
• /
• v.2 no.2
• /
• pp.79-94
• /
• 1986

TM data, which have better resolution in spatial and spectral than MSS data, were used for this study, and several Image Processing Techniques (IPT) were examined for finding the best IPT to fit to lineament extraction and mineralized zone mapping. The Ryeongnam area was selected as test area, because the area is one of major mineralized zones in Korea and its hydrothermal alteration zone is wider and deeper than other areas. The spatial filtering method is most optimum one for limeament extraction: that is, the directional spatial filtering is most efficient to detect N-S, E-W direction lineaments on the image, and the high boost filtering can be applied for mapping all direction lineaments. The ratio method was selected for detecting altered zone. It is possible to make several tens combinations in ratio with 7 bands of TM data, but considering spectral characteristics of each band of TM to the geological meterials and vegetation, the band 4/band 3(A), band 5/band 7(B), and B/A ratio methods were chosen among them. The 5/7 ratio image did not show clearly the altered area due to noise from vegetation cover, so the 4/3 ratio imae was used for trying to decrease the effect of vegetation. As a result the B/A ratio image showed quite nicely the altered zone of the test area. In conclusion, the spatial filtering is the best image processing techniques for lineament mapping, and the B/A ratio image in TM data is useful for the mineralized zone mapping.

• Journal of Environmental Impact Assessment
• /
• v.20 no.4
• /
• pp.477-487
• /
• 2011

In this study, we deduced the best estimation methodology for amount of carbon sequestration by vegetation, through the case study using the data obtainable from the environmental assessment procedure. Our results showed that the estimation methodology using the national vegetation map was the best for the strategic environmental assessment, whileas those using the vegetation growth equation were applicable for environmental impact assessment procedure. Furthermore, we found that the amount of carbon sequestration by farmland and/or grassland, not by vegetation, was not negligible. Therefore, we concluded that the area of farmland and/or grassland need to be taken into account during the landuse planning.