• Ocean Science Journal
• /
• v.43 no.4
• /
• pp.175-182
• /
• 2008

Bottlenose dolphins are the only cetaceans regularly observed in the northern Adriatic Sea, but they survive at low densities and are exposed to significant threats. This study investigates some of the factors that influence habitat use by the animals in a largely homogeneous environment by combining dolphin data with hydrological and physiographical variables sampled from oceanographic ships. Surveys were conducted year-round between 2003 and 2006, totalling 3,397 km of effort. Habitat modelling based on a binary stepwise logistic regression analysis predicted between 81% and 93% of the cells where animals were present. Seven environmental covariates were important predictors: oxygen saturation, water temperature, density anomaly, gradient of density anomaly, turbidity, distance from the nearest coast and bottom depth. The model selected consistent predictors in spring and summer. However, the relationship (inverse or direct) between each predictor and dolphin presence varied among seasons, and different predictors were selected in fall. This suggests that dolphin distribution changed depending on seasonal forcing. As the study area is relatively uniform in terms of bottom topography, habitat use by the animals seems to depend on complex interactions among hydrological variables, caused primarily by seasonal change and likely to determine shifts in prey distribution.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.8 no.3
• /
• pp.73-85
• /
• 2005

Natural disturbance and environmental pressure on natural ecosystems are gradually increasing, and the cause is significantly related to large-scale environmental pollution, global warming, decreasing biodiversity and habitat fragmentation. Environmental impact assessment(EIA) in Korea has been focused on distribution and composition of fauna and flora as major evaluation aspects in ecosystem assessment. It is well known that those characteristics of flora and fauna strongly depend on characteristics and quality of habitat and ecosystem. However, there is no items to assess habitat and ecosystems of spatial ecological system in EIA. Many countries are trying to develop the EIA items to consider the spatial characteristics of habitat and ecosystem and those ecological dynamics as well as species level. In this stream, landscape ecology is emerging discipline to examine spatial pattern and ecological process within/between habitats and ecosystems. Landscape ecological analysis, as a special tool for ecosystem evaluation, has been appropriately adopted to the EIA system in the advanced countries. This review paper tries to introducing the possibilities of landscape ecological concept into the Korean EIA system.

• Journal of Korean Society on Water Environment
• /
• v.34 no.1
• /
• pp.10-25
• /
• 2018

This study was conducted to estimate the habitat suitability of 17 benthic macroinvertebrate taxa in the Hwayang stream. Habitat Suitability Index (HSI) of benthic macroinvertebrates from the Hwayang stream was developed based on three physical habitat factors which include current velocity, water depth, and the substrate. The Weibull model was used as a probability density function to analyze the distribution of individual abundance by physical factors. The number of species and the total individual abundance increased along with the increase in current velocity. By means of Canonical Correspondence Analysis (CCA), the relative importance of each factor was determined in the following order: current velocity, water depth, and the mean diameter. The results depicted that, the most influential factor in the growth of benthic macroinvertebrates in the Hwavang system was current velocity. After comparing the analyzed results from the Hwayang stream with the resukts from the Gapyeong stream, the integrated HSI was drawn. The results indicated that current velocity and substrate had similar distributions of HSI in the two streams. This was due to the addition of unmeasured data from previous surveys, or the fact that benthic macroinvertebrates adapted to deeper waters in the Hwayang Stream. Most taxa showed a clear preference for a fast current velocity, deep water depth and coarse substrate except Baetiella, Epeorus, (mayflies), and Hydropsyche (caddisfly).

• Communications for Statistical Applications and Methods
• /
• v.22 no.6
• /
• pp.575-587
• /
• 2015

The development in data collection techniques results in high dimensional data sets, where discrimination is an important and commonly encountered problem that are crucial to resolve when high dimensional data is heterogeneous (non-common variance covariance structure for classes). An example of this is to classify microbial habitat preferences based on codon/bi-codon usage. Habitat preference is important to study for evolutionary genetic relationships and may help industry produce specific enzymes. Most classification procedures assume homogeneity (common variance covariance structure for all classes), which is not guaranteed in most high dimensional data sets. We have introduced regularized elimination in partial least square coupled with QDA (rePLS-QDA) for the parsimonious variable selection and classification of high dimensional heterogeneous data sets based on recently introduced regularized elimination for variable selection in partial least square (rePLS) and heterogeneous classification procedure quadratic discriminant analysis (QDA). A comparison of proposed and existing methods is conducted over the simulated data set; in addition, the proposed procedure is implemented to classify microbial habitat preferences by their codon/bi-codon usage. Five bacterial habitats (Aquatic, Host Associated, Multiple, Specialized and Terrestrial) are modeled. The classification accuracy of each habitat is satisfactory and ranges from 89.1% to 100% on test data. Interesting codon/bi-codons usage, their mutual interactions influential for respective habitat preference are identified. The proposed method also produced results that concurred with known biological characteristics that will help researchers better understand divergence of species.

• Journal of Ecology and Environment
• /
• v.32 no.3
• /
• pp.183-189
• /
• 2009

This research focused on the effects of fragmentation on moth diversity in an agricultural land-scape by comparing moth species richness and abundance between hillocks and young secondary forests. We examined five sites from the southwestern part of South Korea: three sites from hillock forest and two from secondary forest. We collected moths bi-weekly from April to October for a 2-year period (2006-2007) with a UV light trap that usually attracts moths within 30 meters. Tree species richness and abundance in $20m{\times}20m$ plots at each moth sampling site showed a substantial difference in tree diversity between the two types of forest habitats. The total abundance and richness of moth species were higher in secondary forests (541 species with 4,998 individuals) than in hillock forests (423 species with 3,913 individuals), irrespective of the distance among the sites. An ordination analysis with NMDS showed that habitat is the most important factor of grouping sites. The food preferences of the dominant moth species i,n each habitat were closely related to the habitat type.

• Journal of the Korean Society of Environmental Restoration Technology
• /
• v.11 no.3
• /
• pp.12-19
• /
• 2008

This study was conducted to investigate the draft data for the habitat environment and massive propagation method of Miscanthus changii, which is classified as rare species. The in-site analysis of the native soil give a indication of pH 5.24~5.48, electric conductivity (EC)0.03~0.02 $dS{\cdot}m^{-1}$, organic matter (OM) 1.13~1.15%, Ca 3.4 $mg{\cdot}kg^{-1}$, K 0.25 $mg{\cdot}kg^{-1}$, Mg 0.53 $mg{\cdot}kg^{-1}$, N 0.23%, P 2.15 $mg{\cdot}kg^{-1}$ showed low and 0.33~9.12 $cmol{\cdot}kg^{-1}$ CEC. Growth and tiller number in rhizome propagation of Miscanthus changii showed that horticulture media (perlite 1+vermiculate 1+peat moss 1) is the most suitable soil to habitat. As for seed propagation, germination percentage is 0% (0/20) at first seeding, 2% (1/50) at second seeding and 2.1% (6/280) at third seeding. The average germination percentage was below 2%. This is the reason why Miscanthus changi disappear at habitat of poor soil environment and low germination. We gained 61 plants that 60 rhizome propagation and 1 by seed propagation, renatural to habitat.

• Journal of Forest and Environmental Science
• /
• v.35 no.1
• /
• pp.61-68
• /
• 2019

The purpose of this study is to evaluate the natural habitat of Hotaria unmunsana Doi, which was first discovered at Mt. Unmun also represents a landscape indicator species for Daegu and Gyeongbuk provinces, and Luciola lateralis Motschulsky, which is the object of experiential activation at festivals in some cities in the region. The spatial range of this study is limited by Daegu City and Gyeongbuk province, and is used to predict the preference of firefly for altitude, slope, direction, shaded relief, riparian buffer zone, river environment, and farmland to analyze the area that best matches the habitat of fireflies. As a result, fireflies are highly influenced by altitude and there may be no large-scale habitats in some areas through the Nakdong and the Baekdu mountain ranges, which occur at high altitude. In most of the cities, we found major habitats around the streams and wetlands. By region, the sites were widely distributed around the cities focused on Nakdong River, and many habitats emerged around the Nakdong River tributary and gentle slopes. In order to preserve and spread the habitat of fireflies, the physical environment as well as their relationship with food chains and symbiotic organisms should be established, and excessive use of pesticides and herbicides in agricultural areas should be avoided.

• Korean Journal of Environment and Ecology
• /
• v.36 no.3
• /
• pp.318-326
• /
• 2022

The Convention on Biodiversity (CBD) recommends that 17% of the land be designated as a protected area to counter global environmental problems. Korea also realized a need to designate protected areas according to the international level and explain the significance of designating protected areas. Accordingly, studies on ecosystem services are required. In Korea, the protected areas are designated as national parks, provincial parks, and county parks by hierarchy under the Natural Parks Act. However, as priority was on political and administrative aspects, research on ecosystem service value evaluation and habitat management were concentrated in national parks, and provincial and county parks were relatively neglected. Therefore, more studies on provincial and county parks are necessary. In this study, habitat quality for Gajisan Provincial Park, where there were few studies on habitat management and ecosystem service valuation, was evaluated using the InVEST Habitat Quality model among the InVEST models. The analysis results were compared with 16 mountainous national parks. The results showed that the habitat quality value of Gajisan Provincial Park was 0.83, higher than that of the surrounding areas. The analysis of habitat quality in three districts showed 0,84 for the Tongdosa and Naewonsa districts and 0.83 for the Seoknamsa district. By use district, the nature conservation district, the natural environment district, the cultural heritage district, and the park village district had the highest habitat quality value in that order. Compared with the existing habitat quality analysis results of national parks, Gajisan Provincial Park showed naturalness at the level of Mudeungsan National Park. These results can be used as objective data for establishing policies and management plans to preserve biodiversity and promote ecosystem services in provincial parks.

• Spatial Information Research
• /
• v.15 no.2
• /
• pp.135-146
• /
• 2007

The purpose of this study was to ascertain and analyze environmental factors of subgenus Lycoctonum in Korea for conservation and management of rare high land plant species by GIS. We derived the habitat model of Lycoctonum from GPS coordination, habitat factors and digital topology maps. Suitable altitude fur the subgenus Lycoctonum is from 470m to 1320m, and northern slopes(between 15.5 and 36 degrees) are ideal for the Lycoctonum populations. In addition to altitude, slope and aspect, deciduous forest and approximation to water source were found as important factor. Using GIS and the Lycoctonum habitat model, we overlaid elevation, aspect, slope and land cover layers and analyzed buffer from the water source on two topology maps, Yang-Soo and Mock-Dong. After making prediction map for Lycoctonum habitat, we verified the existence of Lycoctonum populations on the predicted sites through field survey. Through this research, we're convinced that GIS software is powerful tool for plants conservation, such as finding unknown habitat or selecting alternative habitat.

• Korean Journal of Plant Resources
• /
• v.10 no.4
• /
• pp.422-427
• /
• 1997

Vegetation and environment in natural habitats of Aster scaber and Epimedium koreanum around Chunchon was studied to eatablish agroforestry technology for high quality production of wild vegetable. The number of species within the quadrat in natural habitat of Aster scaber was respectively 20, 26, and 25 in Chunchon A, Mt. Yeonyup A, and Mt. Yeonyup B. The number of species within the quadrat in natural habitat of Epimedium koreanum was respectively 15, 32, and 26 in Chunchon B, Bukbangmyon, and Mt. Taeryong. The dominant species in habitat of Aster scaber was respectively Artemisia keiskeana, Disporun smilacinum, and Calamagrostis arundinacea in Chunchon A, Mt. Yeonyup A, and My. Yeonyup B while that in habitat of Epimedium koreanum was respectively Pteridium aquilinum. Artemisia keiskeana, and Disporun smilacinum in Chunchon B, Bukbangmyon, and Mt. Taeryong. Soil pH in habitats of Aster scaber and Epimedium koreanum ranged from 4.5 to 5.3. The contents of organic matter in habitat soil ranged from 1.5% in Chunchon A to 5.5% in Mt. Yeonyup B. The contents of ammonia-nitrogen and nitrate-nitrogen in soil were respectively 0.0043 mg/kg in habitat of Aster scaber and 0.0025mg/kg in habitat of Epimedium koreanum.