• Korean Journal of Remote Sensing
• /
• v.38 no.2
• /
• pp.153-166
• /
• 2022

Waterstorage is one of the factorsthat most directly represent the amount of available water resources. Since the effects of drought can be more intuitively expressed, it is also used in variousstudies for drought evaluation. In a recent study, hydrological drought was evaluated through information on observing reservoirs with optical images. The short observation cycle and diversity of optical satellites provide a lot of data. However, there are some limitations because it is vulnerable to the influence of weather or the atmospheric environment. Therefore, thisstudy attempted to conduct a study on estimating the drought index using Synthetic Aperture Radar (SAR) image with relatively little influence from the observation environment. We produced the waterbody of Baekgok and Chopyeong reservoirs using SAR images of Sentinel-1 satellites and calculated the Reservoir Area Drought Index (RADI), a hydrological drought index. In order to validate the applicability of RADI to drought monitoring, it was compared with Reservoir Storage Drought Index (RSDI) based on measured storage. The two indices showed a very high correlation with the correlation coefficient, r=0.87, Area Under curve, AUC=0.97. These results show the possibility of regional-scale hydrological drought monitoring of SAR-based RADI. As the number of available SAR images increases in the future, it is expected that the utilization of drought monitoring will also increase.

• Korean Journal of Environmental Biology
• /
• v.24 no.4
• /
• pp.359-367
• /
• 2006

The vascular plants of this site were identified as 641 taxa through field investigation; 101 families, 340 genera, 547 species, 80 varieties, 12 forms, 1 subspecies and 1 hybrid. Based on the Rare plants of the Forest Service and Korea Forest Research Institute, 9 taxa were listed except implanted species; Loranthus tanakae, Aristolochia manshuriensis, Aristolochia contorta, Viola albida, Cypripedium macranthum, Schpolia japonioa, Acanthopanax chiisanensis, Rhododendron micranthum. Based on the Korean endemic plants, 18 taxa were listed; Salix purpurea var, japonica, Asarum sieboldii var. mandshuricum for. misnadrum, Persicaria lapathifolia for. alba, Pseudostellaria sylvatica, Aconitum pseudolaeve var. erectum, Corydalis maculata, Corydazis albipetala, Corydalis grandicazyx, Cardamine amaraeiormis, Chrysosplenium barbatum, Filipendula glaberrima, Lespedeza x tomentella, Acanthopanax chiisanensis, Melampyrum setaceum var. nakaianum, Weigela subsessilis, Adenophora triphylla var. hirsute, Cirsium setidens, Saussurea pseudogracilis. Specific plant species by floral region were total 81 taxa (12.6%); Prunus yedoensis in class V, 13 taxa (Thuja orientalis, Cimicifuga heracleiiolia, Sedum middendorffianutn, Rhododendron micranthum, etc.) in class IV, 17 taxa (Equisetum palustre, Aceriphyllum rossii, Angelica gigas, Cirsium setidens, etc.) in class III, 15 taxa (Heloniopsis orientalis, Lychnis cognata, Saxifraga oblongifolia, Viola orientalis, etc.) in class II, 35 taxa (Hosta capitata, Cimicifuga simplex, Chrysosplenium flagelliferum, Campanula punctata, etc.) in class I. So, the naturalized plants were listed 53 taxa and the naturalization index was 8.2%, urbanization index was 20.7%.

• Korean Journal of Environment and Ecology
• /
• v.23 no.2
• /
• pp.105-115
• /
• 2009

The naturalized plants in the Byeonsanbando National Park were listed 88 taxa composed of 24 families, 65 genus, 83 species and 3 varieties and 2 forms by field survey. The naturalized plants divided into pattern by survey of annual plants ratio is 38 taxa (43.2%) by life form spectrum and perennials is 28 taxa (31.8%), biennials is 19 taxa (21.6%), two trees (Robinia pseudoacacia, Ailanthus altissima) and one shrub (Amorpha furticosa) were founded. According to analysis results form place of origin, Europe covered 26 taxa (37.1%), North America covered 23 taxa (32.8%). Naturalized degree 3 plants, as common but not abundant, founded as 28 taxa (31.8%) were hold most highly ratio, naturalized degree 1 plants founded as 8 taxa (9.1%) were hold lowest. Introduction period 1 covered 39 taxa (44.3%) have had highest score and period 2 covered 16 taxa (18.2%) have had lowest scores. In addition, the urbanization index based on 271 taxa was 32.5% and Ambrosia artemisiaefolia is growing by ecosystem disturbing wild plants. Meanwhile, Ambrosia artemisiaefolia have confirmed into district of introduction in the Byeonsanbando National Park were damage the human body of plants develop an allergy to pollen. Therefore, management counterplan of the sequel of monitoring them might be required, introduction into naturalized plants are grasp of ecological characteristics and systematical management plan from this point of time by require.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.15 no.2
• /
• pp.19-29
• /
• 2012

Numerous studies suggested that fish assemblage structure reflects the status of stream ecosystems. The status of streams integrity, including various trophic levels, water quality and habitat degradation, can be assessed by fish assemblages. In this study, we investigated the relationships between fish assemblages and streamline geometry of streams. Previous studies suggested that geomorphologic parameter can be a critical factor of permeability between adjacent two systems. From a landscape ecological perspective, edges may partially control the flow rate of energy between two adjacent systems. Thus, the Streamline geometry can be a geomorphologic parameter that exhibits the integrity of stream. We selected the Nakdong river for study areas, which is one of major rivers and the longest (525 km) River in South Korea. We used the revised IBI representing overall ecological characteristics of Korean fish assemblages and eight sub-assessment criteria of IBI, collected from 82 sampling sites in the Nakdong River. For calculating the Streamline geometry, we measured fractal dimension index that generally used in biology, ecology and landscape ecology. We used the digital land-use/land-cover map and generated a 1-km buffer for each sampling site and refined the shape of the Streamlines. Pearson correlation analyses were performed between Streamline geometry and IBI and sub-assessment criteria of IBI. The results show that IBI and eight sub-assessments of fish are significantly correlated with geometry of Streamline. The fractal dimension of Streamline geometry were related with IBI (r = 0.48) and six sub-assessments of IBI, including total number of native fish and native species, the number of riffle benthic species, sensitive species, tolerant species and native insectivore. Especially, the number of tolerant species(r = -0.52) and native insectivore(r = 0.52) show strong correlation with geometry of Streamline. These results indicate that lower Streamline geometry can result in poor fish assemblages, while higher geometry of Streamline can enhance fish assemblages by potentially supplying insects and better habitat conditions. We expect the results of our study to be useful for stream restoration and management. However, we see the necessity of study investigating the mechanisms how Streamline geometry affect fish assemblages.

• Korean Journal of Environment and Ecology
• /
• v.32 no.1
• /
• pp.66-76
• /
• 2018

This study surveyed the species and population of dragonflies in 20 study sites in the Junam wetland in May and July 2015 to investigate the relationship between the dragonflies and the inhabited environment. We measured the environmental factors such as the area of emergent plants, the area of floating and floating-leaved plants, the area of water surface, the area of water plants, and the nearby land-use type and analyzed the relationship to the dragonfly species, population, and diversity index. We found 757 dragonflies belonging to 21 species of 6 families. The area of floating and floating-leaved plants and the area of water surface affected the species diversity. The area of floating and floating-leaved plants and the area of surface water, in particular, showed the positive correlation with the species richness and the dominance value, respectively. The area of water surface showed the negative correlations with Shannon's diversity index and evenness. Among the type of surrounding land-uses, the dry fields and orchards showed significantly lower average species richness than wetlands. Among the species, Cercion calamorum and Crocothemis servilia were positively correlated with floating and floating-leaved plants. Cercion v-nigrum and Epophthalmia elegans were positively correlated with the area of water surface, and Ischnura asiatica and Ceriagrion nipponicum were negatively correlated. The recent uncontrolled proliferation of lotus colony in the Junam wetland is likely to affect greatly the species composition of dragonflies which have a close relationship with plant species.

• Korean Journal of Environment and Ecology
• /
• v.36 no.5
• /
• pp.525-534
• /
• 2022

In this study, we investigated the psychological and physiological effects of experiences in real natural forests and virtual forests using artificially controllable VR. The experiment tested 60 adult college students in a natural forest and a graduate seminar room where external light was blocked. It evaluated the effects of the natural and the VR forest environments by comparing the psychological and physiological recovery of the subjects. Psychometric testing using the PANAS psychological index showed increased positive emotions and decreased negative emotions after experiencing forest scenery in the natural and VR forest environments. And a stress index, based on measuring cortisol in saliva, decreased significantly in the subjects in both environments. The experiment results can be used to support the creation of a psychological and physiological recovery environment with VR for those who cannot go to the natural forest due to certain restrictions such as physical distance, mobility difficulties, etc. It is expected that the results will be the basis for further research into the visual effects of forest healing and also for widening the use of VR, a technology of the fourth industry, in the field of forestry.

• Journal of the Korean Institute of Landscape Architecture
• /
• v.50 no.6
• /
• pp.30-41
• /
• 2022

This study investigates the heat mitigation effects and thermal comfort improvement due to urban parks during summer. Self-developed monitoring devices to measure long-term microclimate data were installed in three spots, including the park plaza, waterside, and roadside in Seoul Forest Park, and measurements were taken from July 9 to July 30. The results of the measurement are as follows. The daily temperature of the park plaza and waterside were found to be 2.7℃ and 2.9℃ lower than the roadside and 5.5℃ and 7.4℃ lower than the roadside from 10:00 to 16:00. In addition, the Universal Thermal Climate Index (UTCI) measurement was applied to measure the thermal comfort at each point. In the average daily analysis, a significant difference was found between the park plaza, the waterside, and the roadside, and a greater difference was found between 10:00 to 16:00. Also, although there was no significant difference due to the weather condition, a statistically significant difference was also found in the average PM₁₀ and CO₂ concentrations. It is found to be higher in the order from the roadside, park plaza, and waterside for PM₁₀ concentration and park plaza, roadside, and waterside for CO₂. In sum, although the difference in measured microclimate data and thermal comfort index results were different depending on the time and weather conditions at the three points, the park plaza and waterside, which are located inside the park, showed improved thermal comfort conditions and lower temperatures than the roadside outside the park.

• Korean Journal of Environment and Ecology
• /
• v.37 no.5
• /
• pp.403-414
• /
• 2023

This study aimed to evaluate the ecosystem services and environmental sustainability index(ESI) of the Hasidong-Anin coastal sand dune ecological and landscapes conservation area using rapid assessment tools. As a result, the analysis of the environmental sustainability index, derived from the evaluation of ecosystem services in the Hasidong-Anin coastal sand dune ecological and landscapes conservation area, revealed that regulating services, cultural services, and supporting services were all rated below 50%. Especially, cultural and supporting services were identified as lacking. With these results, a SWOT analysis was conducted to develop strategies for enhancing ecosystem services in the Hasidong-Anin coastal sand dune ecological and landscapes conservation area. Six approaches were formulated, involving leveraging strengths as opportunities (SO strategy), minimizing threats using strengths (ST strategy), utilizing opportunities to address weaknesses (WO strategy), and mitigating weaknesses and threats (WT strategy). In the future, when promoting projects to enhance ecosystem services in the Hasidong-Anin coastal sand dune ecological and landscapes conservation area, it will be essential to address issues such as the restoration of currently damaged areas and prevention of future erosion-related damages. This will lead to an elevation of the value of the Hasidong-Anin coastal sand dune ecological and landscape conservation area.

• Journal of Environmental Impact Assessment
• /
• v.33 no.2
• /
• pp.53-63
• /
• 2024

Biodiversity holds significant importance within the framework of environmental impact assessment, being utilized in site selection for development, understanding the surrounding environment, and assessing the impact on species due to disturbances. The field of environmental impact assessment has seen substantial research exploring new technologies and models to evaluate and predict biodiversity more accurately. While current assessments rely on data from fieldwork and literature surveys to gauge species richness indices, limitations in spatial and temporal coverage underscore the need for high-resolution biodiversity assessments through species richness mapping. In this study, leveraging data from the 4th National Ecosystem Survey and environmental variables, we developed a species distribution model using Random Forest. This model yielded mapping results of 24 mammalian species' distribution, utilizing the species richness index to generate a 100-meter resolution map of species richness. The research findings exhibited a notably high predictive accuracy, with the species distribution model demonstrating an average AUC value of 0.82. In addition, the comparison with National Ecosystem Survey data reveals that the species richness distribution in the high-resolution species richness mapping results conforms to a normal distribution. Hence, it stands as highly reliable foundational data for environmental impact assessment. Such research and analytical outcomes could serve as pivotal new reference materials for future urban development projects, offering insights for biodiversity assessment and habitat preservation endeavors.

• Korean Journal of Environment and Ecology
• /
• v.31 no.2
• /
• pp.252-265
• /
• 2017

This study aims to analyze the landscape ecological characteristics of green spaces within built up area of high density and evaluate the potential applicability of green patches, thereby introducing urban garden for generating green networks in residence areas. To this end, Yeoksam-Dong was selected as the site area since it is classified as both green initiative zone and alienated area of park service in Seoul. First, the current condition of green spaces in Yeoksam-Dong was identified by five categories: Street trees, private garden, public pocket garden, rooftop garden, and park. Then, the landscape index analysis through FRAGSTATS and connectivity assessment via multi-buffer zone analysis were carried out for analyzing the green networks and evaluating the potential value of green space. The results showed that the degree to which green areas in the site were distributed is arranged in the order of street tree, private garden, public pocket garden, park, and rooftop garden. In case of the street trees whose total core area (TCA, $1,618m^2$) is as high as the park's ($1,128m^2$). Private garden has potential for green network in built up area of high density by gardening since the shape of the patches are irregular (ED = 78.1m/ha) and the average distance among the patches is close (ENN=33.9m). Public pocket garden has also potential for gardening according to the result that it was found to be distributed evenly (LPI=5.7%, SHEI=0.9) with exposing external disturbance ($TCA=66m^2$). For the green network, 84% of all the study site is covered by small green network in 50m butter range of connected green area. The effect of green network was expected through gardening in public pocket garden (27%) and street tree (26%). Accordingly, it is encouraged to actively utilize street tree, private gardens, and rooftop gardens and to establish the urban gardens like local-based community gardens in public pocket garden where a variety of activities can be carried out near residential areas. By doing so, green networks can effectively be established in built up area with high density. The results of this study can contribute positively to fostering the creation of various types of urban gardens.