• Animal Systematics, Evolution and Diversity
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• no.spc1
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• pp.1-52
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• 1986

The known Korean sertularian hydroid fauna consists of 41 species(including Sertularella areyi reported by Rho, 1974) of 10 genera in two subfamilies. Of which 20 species have been previously known and the following 21 species are newly recorded in Korean waters (Dynamena cornicina, Sertularella distans. Sertularella tongensis, Sertularella obtusa, Sertularella tenella, Sertularella pedrensis, Sertularella gayi, Abietinaria traski, Sertularia desmoides, Sertularia turbinata, Thuiaria suensoni, Thuiaria plumosa. Thuiaria thuia, Thuiaria nuttingi, Thuiaria similis, Thuiaria articulata, Thuiaria carica, Selaginopsis triserialis, Selaginopsis cornigera, Selaginopsis trilateralis and Selagiopsis pinnata). They were sampled from the depths below 100m. Of 41 species Sertularellla miurensis is the most common species and 10 species, Dynamena cornicina, Sertularella distans, Sertularella lagenoides, Sertularella areyi, Sertularella pedrensis, Sertularella gayi, Sertularia hattorii, Sertularia turbinata, Thuiaria plumosa and Thuiaria articulata are scarcesly founded in Korean waters. 25 out of 41 species are shared with Japan and the remaining 16 species so far have been unknown from Japan. The coastal waters of Korea are divided into three regions, the East Sea, the South Sea and the Yellow Sea, on the basis of the geographical distribution and the community coefficient. Concerning the distribution in each region, 11 species occur in the East Sea, 39 species in the South Sea and 23 species in the Yellow Sea The community coefficient between the South Sea and Yellow Sea(0.733) is higher than those of the South Sea-the East Sea (0.476) and the East Sea-the Yellow Sea(0.438).

• Korean Journal of Remote Sensing
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• v.34 no.5
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• pp.787-799
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• 2018

Accurate and effective mapping is critical step to monitor the spatial distribution and change of flood inundated area in large scale flood event. In this study, we try to suggest methods to use low spatial resolution satellite optical imagery for flood mapping, which has high temporal resolution to cover wide geographical area several times per a day. We selected the Sebou watershed flood in Morocco that was occurred in early 2010, in which several hundred $km^2$ area of the Gharb lowland plain was inundated. MODIS daily surface reflectance product was used to detect the flooded area. The study area showed several distinct spectral patterns within the flooded area, which included pure turbid water and turbid water with vegetation. The flooded area was extracted by thresholding on selected band reflectance and water-related spectral indices. Accuracy of these flooding detection methods were assessed by the reference map obtained from Landsat-5 TM image and qualitative interpretation of the flood map derived. Over 90% of accuracies were obtained for three methods except for the NDWI threshold. Two spectral bands of SWIR and red were essential to detect the flooded area and the simple thresholding on these bands was effective to detect the flooded area. NIR band did not play important role to detect the flooded area while it was useful to separate the water-vegetation mixed flooded classes from the purely water surface.

• Journal of the Korean Association of Geographic Information Studies
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• v.9 no.1
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• pp.66-77
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• 2006

Considering constantly increasing number of internet users and information-oriented society with high speed internet network, the application of computer technology is considered to be valuable in urban planning. Particularly, since using Geographic Information System (GIS) is expected to be the best method to convey the information related to the urban planning. Therefore, this study aims at the development of participation system by using GIS and Internet. The system consists of Basic Module, Disposal Module and Decision Support Module. Each module is designed for expressing planning information and processing database, opinion statement and convenience of citizens, and the effectiveness of administration process and decision making. These are connected each other in a basic and simple form, i.e. Java Script and HTML, and the system was realized through data process, Map date and PostGIS for Mapping, and PHP. Last but not least, this system has been tested on the internet and the result indicated its convenience and availability in actual use concluding that participation system has enough application value on urban planning process.

• Korean Journal of Remote Sensing
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• v.36 no.6_1
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• pp.1277-1290
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• 2020

Water resources which is formed of surface and groundwater, are considered as one of the pivotal natural resources worldwide. Since last century, the rapid population growth as well as accelerated industrialization and explosive urbanization lead to boost demand for groundwater for domestic, industrial and agricultural use. In fact, better management of groundwater can play crucial role in sustainable development; therefore, determining accurate location of groundwater based groundwater potential mapping is indispensable. In recent years, integration of machine learning techniques, Geographical Information System (GIS) and Remote Sensing (RS) are popular and effective methods employed for groundwater potential mapping. For determining the status of the integrated approach, a systematic review of 94 directly relevant papers were carried out over the six previous years (2015-2020). According to the literature review, the number of studies published annually increased rapidly over time. The total study area spanned 15 countries, and 85.1% of studies focused on Iran, India, China, South Korea, and Iraq. 20 variables were found to be frequently involved in groundwater potential investigations, of which 9 factors are almost always present namely slope, lithology (geology), land use/land cover (LU/LC), drainage/river density, altitude (elevation), topographic wetness index (TWI), distance from river, rainfall, and aspect. The data integration was carried random forest, support vector machine and boost regression tree among the machine learning techniques. Our study shows that for optimal results, groundwater mapping must be used as a tool to complement field work, rather than a low-cost substitute. Consequently, more study should be conducted to enhance the generalization and precision of groundwater potential map.

• Korean Journal of Medicinal Crop Science
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• v.24 no.5
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• pp.386-392
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• 2016

Background: Sorghum is a major cereal food crop used in many parts of the world. It has been grown on a subsistence level by farmers, under various conditions of environmental stresses in the semi-arid tropics of Africa and Asia. This plant has received significant attention because of its ability to reduce cholesterol in the blood, and its anti-dementia, antioxidant, and antimicrobial properties. It is possible to develop a functional and commercially viable sorghum variety by using superior cultivars of sorghum. The objective of this study was to build a database of superior sorghum accession. Methods and Results: We used 250 sorghum accessions collected from different geographical bioregions in Korea. We determined various agronomic characters including germination rate and ear length of these accessions. To determine the antioxidant capacity, we measured the 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity, 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt radical scavenging activity, total phenolic contents, and total flavonoid contents. Accession 189 showed higher germination (> 80%) than the other accessions. Higher 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity was observed in 11-SB-078 ($RC_{50}$; $1.89{\pm}2.88{\mu}g/m{\ell}$), and higher 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)-diammonium salt radical scavenging activity was recorded in 11-SB-116 ($RC_{50}$; $35.48{\pm}2.42{\mu}g/m{\ell}$) than in the other accessions. The ear length ranged from 15 cm to 48 cm, the total phenolic contents ranged from $3mg{\cdot}GAE/g$ to $77mg{\cdot}GAE/g$, and total flavonoid contents ranged from $0.09mg{\cdot}QE/g$ to $1.07mg{\cdot}QE/g$. Conclusions: Among 250 sorghum accessions, we selected 10 with both superior agronomic characters and highly functional food quality.

• Korean Journal of Ecology and Environment
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• v.44 no.2
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• pp.195-202
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• 2011

This study analyzed and modeled the relationships between the probabilities of two exotic species occurrence (i.e. largemouth bass and blue gill) and environmental factors such as climatic and geographical variables using Generalized Additive Models (GAM), Generalized Liner Models and Classification Tree Analysis (CTA). The most moderate occurrence probability of largemouth bass was predicted using GAM with an area under the curve (ADC) of 0.88 and Kappa of 0.42, while those of blue gill was suggested by using CTA with an AUC of 0.92 and Kappa of 0.44. The most significant environmental variable in terms of changes in deviance for both species was the annual air temperature for the occurrence probability. Dams had stronger effect on the occurrence of largemouth bass than blue gill. Model development and prediction for the occurrence probability of fish species and richness are necessary to prevent further spread of exotic fishes such as largemouth bass and blue gill because they can threaten habitats of native river ecosystem through various mechanisms.

• Korean Journal of Agricultural and Forest Meteorology
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• v.10 no.1
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• pp.1-8
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• 2008

The concept of growing degree-days (GDD) is widely accepted as a tool to relate plant growth, development, and maturity to temperature. Information on GDD can be used to predict the yield and quality of several crops, flowering date of fruit trees, and insect activity related to agriculture and forestry. When GDD is expressed on a spatial basis, it helps identify the limits of geographical areas suitable for production of various crops and to evaluate areas agriculturally suitable for new or nonnative plants. The national digital climate maps (NDCM, the fine resolution, gridded climate data for climatological normal years) are not provided on a daily basis but on a monthly basis, prohibiting GDD calculation. We applied a widely used GDD estimation method based on monthly data to a part of the NDCM (for Hapcheon County) to produce the spatial GDD data for each month with three different base temperatures (0, 5, and $10^{\circ}C$). Synthetically generated daily temperatures from the NCDM were used to calculate GDD over the same area and the deviations were calculated for each month. The monthly-data based GDD was close to the reference GDD using daily data only for the case of base temperature $0^{\circ}C$. There was a consistent overestimation in GDD with other base temperatures. Hence, we estimated spatial GDD with base temperature $0^{\circ}C$ over the entire nation for the current (1971-2000, observed) and three future (2011-2040, 2041-2070, and 2071-2100, predicted) climatological normal years. Our estimation indicates that the annual GDD in Korea may increase by 38% in 2071-2100 compared with that in 1971-2000.

• Korean Journal of Agricultural and Forest Meteorology
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• v.22 no.2
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• pp.47-56
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• 2020

Decline of pine forests happens in Korea due to various disturbances such as insect pests, forest fires and extreme climate, which may further continue with ongoing climate change. For conserving and reestablishing pine forests, understanding climate-induced future shifts of pine tree distribution is a critical concern. This study predicts future geographical distribution of Pinus densiflora, using Maximum Entropy Model (MaxEnt). Input data of the model are locations of pine tree stands and their environmental variables such as climate were prepared for the model inputs. Alternative future projections for P. densiflora distribution were conducted with RCP 4.5 and RCP 8.5 climate change scenarios. As results, the future distribution of P. densiflora steadily decreased under both scenarios. In the case of RCP 8.5, the areal reductions amounted to 11.1% and 18.7% in 2050s and 2070s, respectively. In 2070s, P. densiflora mainly remained in Kangwon and Gyeongsang Provinces. Changes in temperature seasonality and warming winter temperature contributed primarily for the decline of P. densiflora., in which altitude also exerted a critical role in determining its future distribution geographic vulnerability. The results of this study highlighted the temporal and spatial contexts of P. densiflora decline in Korea that provides useful ecological information for developing sound management practices of pine forests.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.3
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• pp.364-372
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• 1995

On the outbreak of paralytic shellfish poisoning in April 1993 in most of shellfish harvesting areas in Jinhae Bay, Korea, to clarify the toxin production of causative organism Alexandrium species, 19 axenic clonal isolates established from the benthic resting cysts in three different stations of those culture grounds were subjected to PSP toxin analysis by HPLC. Individual toxin content per cell was highly variable among the strains isolated from a sampling area and originated from an individual cyst. Average toxin contents in those areas revealed higher values of 54-70 fmol/cell. Toxin profiles included C1/C2(epiGTX8/GTX8), GTX1/GTX4 and neoSTX as the major components, and GTX2/GTX3, GTX5, C4, dcSTX and STX as the minor or sporadic ones. neoSTX on the dominant toxins showed not only most diverse compositional changes comprising $5-54 mol\%$ ranges but also no detection on the half of the strains examined, which were implicated in arising of heterogeneity with a genetic trait within a geographical region. When average toxin composition was compared, carbamate toxins comprised large proportions of $57\%,\;54\%\;and\;67\%$ as total toxin in St. 1, St. 2 and St. 4, respectively. These results suggested that an extensive paralytic shellfish toxification in Jinhae Bay could be largely due to the production of highly potent carbamate toxins in the causative dinoflagellate Alexandrium species.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.419-428
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• 2013

We identified the diversity, geographical distribution, ecological characteristics of birds, trees, and flowers species designated as local government symbols as a means for understanding public awareness on biodiversity. A total of 114 species including 48 birds, 40 flowers, 36 tree species belonging to 40 orders 59 families 90 genus were designated as natural symbols. Pica pica (L.) in birds, Rhododendron schlippenbachii Maxim. among flowers, have also been designated as symbols. The tree Ginkgo biloba L. was designated with the highest frequency. Local governments located coastal area were selected bird species of the Laridae family and the tree species Camellia japonica L., of Pinaceae as their natural symbols. In contrast, local governments located inland have designated resident bird species such as P. pica and Columba rupestris (Pallas) and flower species from the Ericaceae as natural symbols widely distributed and easily observed throughout South Korea. However, many local governments have designated the same species as a natural symbol based on their size color and public appeal and popularity. The information about the popular species and their ecological traits are useful for establishing the criteria as flagship or iconic species selection and their roles in habitat conservation.