• Ocean and Polar Research
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• v.32 no.1
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• pp.53-61
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• 2010

The distribution of coral reefs can be an indicator of environmental or anthropogenic impacts. Here, we present a habitat map of coral reefs developed using high-spatial satellite images. The study area was located on the north-eastern part of Weno island, in the Chuuk lagoon of Federated States of Micronesia. Two fieldwork expeditions were carried out between 2007 and 2008 to acquire optical and environmental data from 121 stations. We used an IKONOS image obtained in December 2000, and a Kompsat-2 image obtained in September 2008 for the purpose of coral reef mapping. We employed an adapted version of the object-based classification method for efficient classification of the high-spatial satellite images. The habitat map generated using Kompsat-2 was 72.22% accurate in terms of comparative analysis with in-situ measurements. The result of change detection analysis between 2000 and 2008 showed that coral reef distribution had decreased by 6.27% while seagrass meadows had increased by 8.0%.

• Water Engineering Research
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• v.2 no.1
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• pp.33-48
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• 2001

For the design of suitable aquatic habitats and habitat management purposes, sensitive descriptors for aquatic areas were identified and analyzed. The classification system of the aquatic areas were developed for natural streams and modified streams in Korea. Relationships among the descriptors of an aquatic area such as channel width, meander wave length, and arc angle have been defined. The analysis indicates that the total mean sinuosity is 1.25 for the main channels of natural streams, whereas the mean value of the sinuosity of modified streams is 1.14. The mean values of the total area, the width, and the length for the sandbars of natural streams are larger than those of modified streams.

• Journal of Korean Society on Water Environment
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• v.33 no.6
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• pp.728-735
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• 2017

Many restoration projects are underway to revive disturbed streams. In order to achieve successful stream restoration, a variety of microhabitats should be created to promote biological diversity. Research on biological classification of microhabitats is essential for biological diversity. However, research on classification using only physical environmental factors has been carried out. The purpose of this study is to classify and quantify the microhabitat of the stream by using macroinvertebrates systematically. In this study, eight wadeable streams and four non-wadeable streams were surveyed to identify the benthic macroinvertebrates in these various microhabitats. Among the physical environmental factors (current velocity, water depth, substrate), the particle size of the substrate was the most influential factor in the emergence of the Habitat Orientaion Groups. Among the HOGs, clinger and burrower were highly correlated with physical environment factors and showed the opposite tendency. The distribution of clinger and burrower according to the physical environmental factors showed two tendencies based on the current velocity (0.3 m/s) and water depth (0.4 m). In addition, the particle size of the substrate showed three trends (${\leq}-5.0$, -5.0 < mean diameter ${\leq}-2.0$, > -2.0). Based on the abundance tendency of these two HOGs, the microhabitats were classified into nine types, from a eupotamic microhabitat to a lentic microhabitat. Classification of the microhabitats using HOGs can be employed for creating microhabitats to promote biological diversity in future stream restoration plans.

• Journal of Wetlands Research
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• v.10 no.2
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• pp.173-178
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• 2008

The habitat composition in the Han-river estuary, where white-naped crane(Grus vipio; endangered migrating bird) spend winter, was analysed by the geographic information system(GIS). And the habitat use pattern of white-naped crane collected by satellite tracking method was analysed. The % composition of seven habitat categories of land cover classification was compared for the buffers of radii 100 m, 200 m, 500 m, and 1 km, respectively, around the white-naped crane position point(n=228), and the statistical analysis was done using chi-square test. The results showed no selective use of habitat area by white-naped crane in the buffers of 100 m, 200 m and 500 m, but showed clear selection of habitat use (p < 0.05) in the case of 1 km buffer.

• Journal of the Korean Institute of Landscape Architecture
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• v.32 no.4
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• pp.28-38
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• 2004

Korean goral (Nemorhaedus caudatus raddeanus) is one of the endangered species in Korea, and the rugged terrain of the Soraksan National Park (373㎢) is a critical habitat for the species. But the goral population is threatened by habitat fragmentation caused by roads and hiking trails. The objective of this study was to develop a potential habitat suitability model for Korean goral in the park, and the model was based on the concepts of fuzzy set theory and multi-criteria evaluation. The process of the suitability modeling could be divided into three steps. First, data for the modeling was collected by using field work and a literature survey. Collected data included 204 points of GPS data obtained through a goral trace survey and through the number of daily visitors to each hiking trail during the peak season of the park. Second, fuzzy set theory was employed for building a GIS data base related to environmental factors affecting the suitability of the goral habitat. Finally, a multiple-criteria evaluation was performed as the final step towards a goral habitat suitability model. The results of the study were as follows. First, characteristics of suitable habitats were the proximity to rock cliffs, scattered pine (Pinus densiflora) patches, ridges, the elevation of 700∼800m, and the aspect of south and southeast. Second, the habitat suitability model had a high classification accuracy of 93.9％ for the analysis site, and 95.7％ for the validation site at a cut off value of 0.5. Finally, 11.7％ of habitatwith more than 0.5 of habitat suitability index was affected by roads and hiking trails in the park.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.11 no.3
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• pp.28-38
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• 2008

The purpose of this study are to compare existing presence-absence predictive models and to predict suitable habitat for Goral (Nemorhaedus caudatus raddeanus) that is an endangered and protected species in Seoraksan national park using the best model among existing predictive models. The methods of this study are as follows. First, 375 location data and 9 environmental data layers were implemented to build a model. Secondly, 4 existing presence-absence models : Generalized Linear Model (GLM), Generalized Addictive Model (GAM), Classification and Regression Tree (CART), and Artificial Neural Network (ANN) were tested to predict the Goal habitat. Thirdly, ROC (Receiver Operating Characteristic) and Kappa statistics were used to calculate a model performance. Lastly, we verified models and created habitat suitability maps. The ROC AUC (Area Under the Curve) and Kappa values were 0.697/0.266 (GLM), 0.729/0.313 (GAM), 0.776/0.453 (CART), and 0.858/0.559 (ANN). Therefore, ANN was selected as the best model among 4 models. The models showed that elevation, slope, and distance to stream were the significant factors for Goal habitat. The ratio of predicted area of ANN using a threshold was 31.29%, but the area decreased when human effect was considered. We need to investigate the difference of various models to build a suitable wildlife habitat model under a given condition.

• Journal of The Geomorphological Association of Korea
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• v.24 no.4
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• pp.57-73
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• 2017

The formation of the lava dam of the paleo lake blocked the entrance to the Chatancheon River on the Jeongok lava plateau and it suddenly transformed the terrestrial ecosystem into the aquatic one by the overflow. The spiders in the lava dam adapted in the wetland and evolved into water spiders that could survive by forming bubble houses. Since then, the lava dam was connected to the present Hantangang River due to the dissection and the lake became a terrestrial environment, a small area of marsh composed of primarily clay soil layer. Change in water level of the habitat and thus the extension of the terrestrial area made the species a endangered now. This study carried out frequency of occurrence, degree of wetness and plant habitats of the vascular plant in the water spider habitat. As a result of this study, total 180taxa are of 55 (30.6%) wetland plant groups and of 113 (62.8%) upland plant groups except facultative plant groups. Among the wetland plant groups, the Isachne globosa community occupied the largest area, where the water spiders were most observed. The result of this study, the classification and the types of vascular plant species, would provide useful information for the sustaining healthy wetland ecosystem and the restoration of the habitat for the water spiders.

• Ecology and Resilient Infrastructure
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• v.1 no.2
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• pp.82-93
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• 2014

In recent years, "ecological river restoration" taking into account the flood control, water utilization and environmental aspects of rivers is actively being investigated. However, it is hard to understand the inhabitation conditions of living organisms that live on the river with distinct characteristics have been fully reflected, and with the use of limited methods, it ends in uniformed composition of artificial rivers and a mere customary stream channel maintenance, resulting in frequently disturbed stream channel habitats As a fundamental study for investigating the habitats of living organisms that live on rivers, this study intends to examine each habitat type by dividing domestic rivers into sand rivers and gravel rivers depending on the nature of rivers and dividing sections of each river into central river sections and natural river sections. As a result, more diverse habitat types of organisms were found in the gravel rivers rather than in the sand rivers, and the habitat types of organisms in the central river sections where the river restoration project have been already conducted reached approximately 56.3 % of those that appeared in the natural river sections.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.16 no.2
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• pp.53-69
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• 2011

Classification of estuaries based on their multi-component and multidisciplinary processes is important for the systematic management of estuaries. In this study, an integrated GlS-based analysis system including high resolution aerial photographies and topographic maps was used to classify 463 estuaries based on estuarine circulation pattern, geomorphological feature, natural habitat distribution and characteristics of land use. These estuaries were divided into two basic types, open and closed. Two hundred and thirty five systems were open estuaries comprising of forty one mountainous type (OM), eighty sevcn sandpit type (OS) and one hundred seven funnel type (OF). Each type of open estuary was further classified into three types based on habitat distribution and land use characteristics resulting in total ninc types of open estuaries. Two hundred and twenty eight estuaries were closed systems comprising of one hundred and forty four blocked type (CB directly) and eighty four lake type (CL, indirectly). CB type estuary was further classified into three types based on habitat distribution and land use characteristics. This estuarine classification scheme can be applied to provide a framework for effective management strategies of individual estuaries to estimate the management priority and strategy.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.18 no.1
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• pp.1-12
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• 2015

Beginning of the human ecology in 1920s, the efforts for applying the environmental values to a policy have been embodied by the enactments of international agreement and relevant laws. The government has been struggling to adopt the environmental values for the policy by enacting the relevant laws and establishing the environmental value evaluation information (environmental conservation value assessment map, eco-natural map, biotope map). In spite of the efforts to apply the environmental value assessment information for the habitat potential of wildlife, the application is being challenged by the discrepancy in methods and criteria. Thus this study intends to measure the potential of wildlife habitat and apply it to the spatial value classification for the application plan of wildlife habitat potential in policy. Maxent was used for the habitat potential and the land types were classified depending on the surface and land use pattern of cadastral map. As a result, the policy matrix including conservation strategy(CS), restoration strategy(RS), practical use strategy(PS) and development strategy(DS) has been deduced as CS $13.05km^2$(2.38%), RS $1.64km^2$(0.30%), PS $162.42km^2$(29.57%) and DS $8.56km^2$(1.56%). CS was emerged mostly on forest valleys and farmlands, and RS was appeared in the road area near the conservation strategy areas. Boryung downtown and Daecheon Beach were the center of DS, while the forest and farmlands were presented as PS. It is significant that this study suggest the new approaching method by comparing the wildlife habitat potential with the land type. Since this study evaluated the environmental value by one species of leopard cat (Prionailurusbengalensis) with Maxent model, it is necessary to apply the habitat potential measuring method for various target species as further research.