• Journal of Ecology and Environment
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• v.47 no.3
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• pp.75-84
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• 2023

Background: Knowledge of the spatial trends of plant invasions in different habitats is essential for a better understanding of the process of these invasions. We examined the variation in invasive alien plant species (IAS) richness and composition at two spatial scales defined by elevation and habitat types (roadside, forest, and cultivated lands) in the Makawanpur district of Nepal. Following an elevation gradient ranging from 500 to 2,400 m asl along a mountain road, plant species cover was recorded within sample plots of size 10 m × 5 m. Systematic random sampling was adopted in every 100 m elevation intervals on three habitat types. Results: Altogether 18 invasive alien plants belonging to eight families were recorded within 60 plots, of which 14 species (representing 80%) were from tropical North and South America. The most common plants by their frequency were Ageratina adenophora, Chromolaena odorata, Bidens pilosa, Lantana camara, and Parthenium hysterophorus. We found a significant relationship between species composition and elevation in the study area. Low-elevation regions had a higher number of alien species as compared to high-elevation regions within different habitat types. Conclusions: The species richness and density of IAS were higher in the road site followed by the cultivated land and forest sites. This pattern occurred throughout the elevation range and habitats. IAS were found mostly in the open land with high sunlight availability. Information from such scientific assessment of invasive alien plants will assist in developing appropriate management plans in the Makawanpur district.

• Journal of Korea Water Resources Association
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• v.51 no.8
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• pp.713-727
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• 2018

This study is to develop an assessment system for stream physical environments by considering stream characteristics. Comprehensively, the descriptions of and steam classification, assessing reach selection, contents of assessment categories and indexes are summarized. Since the physical structure of stream is results of reaction by stream power, streams were classified into three types (as high gradient stream, mid gradient stream and low gradient stream) according to the slope of channel, the grain size of bed material and the characteristics of channel topography. The scale of assessment reach was selected based on 10 or 25 times of channel width according to typical characteristics such as interval of step or riffle and sinuosity in each stream type. The assessment indexes were organized into common indicators such as channel stability, flow status, cross-section shape, bank stability, channel alteration and stream crossing structure, and characteristic indicators by stream type such as effective habitats, bed embeddedness, diversity of flow and frequency of step or riffle. To evaluate the applicability, the assessment system was applied to 9 streams and the results were analyzed and presented.

• Korean Journal of Radiology
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• v.24 no.3
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• pp.235-246
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• 2023

Objective: It is difficult to predict the treatment response of tissue after stereotactic radiosurgery (SRS) because radiation necrosis (RN) and tumor recurrence can coexist. Our study aimed to predict tumor recurrence, including the recurrence site, after SRS of brain metastasis by performing a longitudinal tumor habitat analysis. Materials and Methods: Two consecutive multiparametric MRI examinations were performed for 83 adults (mean age, 59.0 years; range, 27-82 years; 44 male and 39 female) with 103 SRS-treated brain metastases. Tumor habitats based on contrast-enhanced T1- and T2-weighted images (structural habitats) and those based on the apparent diffusion coefficient (ADC) and cerebral blood volume (CBV) images (physiological habitats) were defined using k-means voxel-wise clustering. The reference standard was based on the pathology or Response Assessment in Neuro-Oncologycriteria for brain metastases (RANO-BM). The association between parameters of single-time or longitudinal tumor habitat and the time to recurrence and the site of recurrence were evaluated using the Cox proportional hazards regression analysis and Dice similarity coefficient, respectively. Results: The mean interval between the two MRI examinations was 99 days. The longitudinal analysis showed that an increase in the hypovascular cellular habitat (low ADC and low CBV) was associated with the risk of recurrence (hazard ratio [HR], 2.68; 95% confidence interval [CI], 1.46-4.91; P = 0.001). During the single-time analysis, a solid low-enhancing habitat (low T2 and low contrast-enhanced T1 signal) was associated with the risk of recurrence (HR, 1.54; 95% CI, 1.01-2.35; P = 0.045). A hypovascular cellular habitat was indicative of the future recurrence site (Dice similarity coefficient = 0.423). Conclusion: After SRS of brain metastases, an increased hypovascular cellular habitat observed using a longitudinal MRI analysis was associated with the risk of recurrence (i.e., treatment resistance) and was indicative of recurrence site. A tumor habitat analysis may help guide future treatments for patients with brain metastases.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.3
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• pp.109-118
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• 2015

This study was performed to propose the site selection plan for the restoration of the target Reeve's turtle (Maunemys reevesii) habitat and has developed the AHP model to select the optimal site for Reeve's turtle habitat restoration on the basis of the Reeve's turtle Habitat Suitability Index (HSI) items (factors and variables). The assessment areas were established by the Reeve's turtle HSI factors such as breeding space, feed, cover, water, threatening factors and others and the sub-assessment items by each assessment area were established based on the Reeve's turtle HSI variables. The weighting values of the assessment areas and items were calculated by the developed AHP method. The weighting values of the 5 assessment areas were arranged in order as breeding space(0.293), food(0.273), water(0.217), cover(0.113), and threatening factor(0.104). The final weighting values of the 17 assessment items were arranged in order of height as all kind of food(0.222), water depth(0.096), altitude of spawning ground(0.093). The scoring criteria according to the assessment items and factors were marked and applied by equal intervals considering the criteria by HSI items of the Reeve's turtle and finally the scoring criteria diagram as been proposed for the optimal site selection of the Reeve's turtle habitat restoration.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.8 no.3
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• pp.53-66
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• 2005

The objective of this study is the classification of priority areas for the implementation of green roof by evaluating environmental deterioration in Seoul. Non-permeable pavement, air pollution, habitual floods, energy use, heat island and green space are considered in this assessment indicators. The expert questionnaire survey was conducted in order to determine the most important indicators. These indicators were then, thoroughly evaluated. As a result, high priority areas for the implementation of green roof were deduced in the following order of the districts : Jung, Sungdong, Jungrang, Youngdungpo, Jongro and Kangnam. The highest priority areas were determined to be crowded business-commercial areas. Low priority areas are analyzed in the following order of the districts : Kwanak, Nowon, Seocho and Dobong. The result of this study can be utilized for environmental planning and decision of related policies. Additionally, it can be promoted that awareness of implementing green roof of citizens, policy makers and building owners and effect of green networking between inside and outside Seoul can be increased.

• Environmental Engineering Research
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• v.13 no.3
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• pp.107-111
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• 2008

Water quality contamination issues are of critical concern to human health, whilst pesticide release generated from irrigated land should be considered for protecting natural habitats and human health. This paper suggests new method for evaluation and analysis using the GIS technique based on integrated spatial modeling framework. The pesticide use on irrigated land is a subset of the larger spectrum of industrial chemicals used in modern society. The behavior of a pesticide is affected by the natural affinity of the chemical for one of four environmental compartments; solid matter, liquid, gaseous form, and biota. However, the major movements are a physical transport over the ground surface by rainfall-runoff and irrigation-runoff. The irrigated water carries out with the transporting sediments and makes contaminated water by pesticide. This paper focuses on risk impact identification and assessment using GIS technique. Also, generated data on pesticide residues on farmland and surface water through GIS simulation will be reflected to environmental research programs. Finally, this study indicates that GIS application is a beneficial tool for spatial pesticide impact analysis as well as environmental risk assessment.

• Journal of Korean Society for Geospatial Information Science
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• v.20 no.3
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• pp.11-18
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• 2012

Increasing concern about biodiversity has lead to a rise in demand on the spatial assessment of biological resources such as biodiversity assessment, protected area selection, habitat management and restoration in Korea. The purpose of this study is to create species richness map through data collection and modeling techniques for wildlife habitat assessment. The GAM (Generalized Additive Model) is easy to interpret and shows better relationship between environmental variables and a response variable than an existing overlap analysis and GLM (Generalized Linear Model). The study area delineated by a large watershed contains Jirisan national park, Mt. Baekun and Sumjin river with three kinds of protected areas (a national park, a landscape ecology protected area and an otter protected area). We collected the presence-absence data for wildlife (mammals and birds) using a stratified random sampling based on a land cover in the study area and implemented natural and socio-environmental data affecting wildlife habitats. After doing a habitat use analysis and specifying significant factors for each species, we built habitat suitability models using a presence-absence model and created habitat suitability maps for each species. Biodiversity maps were generated by taxa and all species using habitat suitability maps. Significant factors affecting each species habitat were different according to their habitat selection. Although some species like a water deer or a great tit were distributed at the low elevation, most potential habitats for mammals and birds were found at the edge of a national park boundary or near a forest around the medium elevation of a mountain range. This study will be used for a basis on biodiversity assessment and proected area selection carried out by Ministry of Environment.

• Journal of Environmental Impact Assessment
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• v.28 no.3
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• pp.287-298
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• 2019

This study found that wildlife crossing created through environmental impact assessments didn't reduce the number of wildlife accidents on the road by review of "A Study on the Legal and Institutional Review for Reproving Bio-Mobile in Environmental Impact Assessment(2018)". Specific considerations to be reviewed at each stage of the environmental impact assessment consultation were presented for practical site application. Therefore, in this study, the consultation steps for environmental impact assessment were presented in five stages, including planning, design, construction, monitoring, maintenance and management, and detail of the items to be reviewed by public officer. It will be able to prevent loss of habitats and improve biodiversity by improving the practice and institutional problems that were planned and designed at the time of construction.

• Journal of Environmental Impact Assessment
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• v.22 no.3
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• pp.277-290
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• 2013

This study was carried out to propose the new procedure to apply Habitat Evaluation Procedure(HEP) of target species using delphi technique, which is suitable to develop endangered species with few researches and ecological knowledges. To identify habitat quality of specific species in development project site, we can develop habitat model and create habitat suitability maps. In this study, we select the Common Kestrel(Falco tinnunculus) as target species in four areas(Paju, Siheung, Ansan, Hwaseong) which is located near the Seoul metropolitan area. The Delphi technique was selected to get the reliable information on the species and habitats requirements. Through the delphi approach, seven habitat components were determined as suitable variables for the Common Kestrel: density($n/km^2$) of small mammals, area($km^2$) of bare-grounds, pasturelands and riparian, and open area(%), spatial distribution and area of croplands, landscape diversity, breeding sites(tall trees, cliffs, high-rise buildings), and the length of shelf. Habitat variables used in this model were classified into two categories: % of suitable land-cover type(open areas, croplands, pasturelands, wetlands, and baregrounds) and the quality of feeding sites(within 250m from edges of woodlands). Habitat quality of the Common Kestrel was assessed against occurred sites derived from the nationwide survey. Predicted habitat suitability map were closely related to the observed sites of the endangered avian species in the study areas. With the habitat suitability map of the Common Kestrel, we assess the environmental impacts with habitat loss after development project in environmental impact assessment.

• Journal of Environmental Impact Assessment
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• v.19 no.4
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• pp.381-396
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• 2010

It is essential to consider strategies, spatial planning, and reflection of sustainability for the creation of sound urban spaces. To this end, there is a need for plans that can secure better sustainability through strategic environmental assessment (SEA) of plans. This study examined the literature and available precedent to develop a SEA model for administrative plans for urban development including metropolitan plans, urban master plans and urban management plans. In the course of development of the model, environmental issues associated with the urban plans were analyzed by classifying them into ten categories, including "spatial planning," "conservation planning," "greenbelt systems," "habitats." and etc. according to their rank. Furthermore, those issues were reflected on the development of environmental evaluation indices for the plans. Overall and detailed environmental indices that can be applied to the administrative plans for urban development including metropolitan plans, urban master plans and urban management plans were devised for five stages: (1) Establishment of development goals and strategy, (2) Analysis of current status and characteristics, (3) Conceptualization of spatial structure, (4) Planning for each department, and (5) Execution and management. Sub plans are more detailed and concrete. Criteria based on the evaluation indices, when performing evaluations on plans based on each environmental assessment index in reference to experts and the literature, were used to forecast their effects, i.e. whether they had a positive, negative, or no effect or relationship, or whether their effects was uncertain. Based on the forecasts, this study then presents means to establish more improvable plans. Furthermore, by synthesis of the effects according to each index and integration of the process, plans were analyzed overall. This study reflects the characteristics of the present time period based on issues in the SEA process and techniques in upper level administrative plans being newly established, and presents them according to the stage of each plan. Furthermore, by forecasting the effect of plans by stage, this study presents proposals for improvement, and in this aspect, can be meaningful in promoting plan improvements through SEA.