• Korean Journal of Environment and Ecology
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• v.29 no.3
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• pp.333-343
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• 2015

This research aims at identifying the goshawk's possible and replaceable breeding ground by using the MaxEnt prediction model which has so far been insufficiently used in Korea, and providing evidence to expand possible protection areas for the goshawk's breeding for the future. The field research identified 10 goshawk's nests, and 23 appearance points confirmed during the 3rd round of environmental research were used for analysis. 4 geomorphic, 3 environmental, 7 distance, and 9 weather factors were used as model variables. The final environmental variables were selected through non-parametric verification between appearance and non-appearance coordinates identified by random sampling. The final predictive model (MaxEnt) was structured using 10 factors related to breeding ground and 7 factors related to appearance area selected by statistics verification. According to the results of the study, the factor that affected breeding point structure model the most was temperature seasonality, followed by distance from mixforest, density-class on the forest map and relief energy. The factor that affected appearance point structure model the most was temperature seasonality, followed by distance from rivers and ponds, distance from agricultural land and gradient. The nature of the goshawk's breeding environment and habit to breed inside forests were reflected in this modeling that targets breeding points. The northern central area which is about $189.5 km^2$(2.55 %) is expected to be suitable breeding ground. Large cities such as Cheongju and Chungju are located in the southern part of Chungcheongbuk-do whereas the northern part of Chungcheongbuk-do has evenly distributed forests and farmlands, which helps goshawks have a scope of influence and food source to breed. Appearance point modeling predicted an area of $3,071 km^2$(41.38 %) showing a wider ranging habitat than that of the breeding point modeling due to some limitations such as limited moving observation and non-consideration of seasonal changes. When targeting the breeding points, a specific predictive area can be deduced but it is difficult to check the points of nests and it is impossible to reflect the goshawk's behavioral area. On the other hand, when targeting appearance points, a wider ranging area can be covered but it is less accurate compared to predictive breeding point since simple movements and constant use status are not reflected. However, with these results, the goshawk's habitat can be predicted with reasonable accuracy. In particular, it is necessary to apply precise predictive breeding area data based on habitat modeling results when enforcing an environmental evaluation or establishing a development plan.

• Korean Journal of Environment and Ecology
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• v.24 no.1
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• pp.62-68
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• 2010

This study was conducted to find out how the germination, phenology and leaf morphology of Phytolacca insularis(endemic species of Korea) and P. americana(alien species) react to the global warming situation. Seed and seedlings of two species were sampled and placed under two separate conditions for the experiment. One of the seed and seedlings was treated in the glass house with control(ambient $CO_2$+ambient temperature, (AC-AT), and the other with control(elevated $CO_2$+ elevated temperature, EC-ET), over the period of one year, 2008-2009. The germination rate of two species was fast, and the time of their germination started early, when they were treated at EC-ET than at AC-AT. Furthermore, the germination rate of Phytolacca insularis(endemic species of Korea) was found to be comparatively lower than that of P. americana(alien species). The former showed only vegetative growth whereas the latter showed both vegetative growth and reproductive growth in one year period. The more $CO_2$ degree and temperature increased, phenological responses of two species, including leaf growth, the formation of flower stems, flowering, and fruit maturing, became much faster, and the time of their leaf-yellowing was delayed. The lamina length of P. insularis was not significantly affected by elevated $CO_2$ and temperature. The lamina length of P. americana, on the other hand, became longer at EC-ET than at AC-AT, but the leaf width of both species increased at EC-ET. As for the number of leaves, both species showed no difference. Finally, the ratio of the leaf area of P. insularis was high at AC-AT, but P. americana was high at EC-ET. These results indicate that P. americana, aliens species, reacts more sensitively to global warming than P. insularis, endemic species, does.

• Korean Journal of Environment and Ecology
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• v.24 no.1
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• pp.14-25
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• 2010

This study was carried out to investigate the soil salinity and salt spray drift of the indigenous windbreak trees, and its main purpose was to provide basic data for the selection of salt-tolerant trees in the saline coastal region in the South Sea of Korea. The soil salinity($EC_{1:5}$)was $0.18dSm^{-1}$, which was an average degree of the whole areas of investigation whose salinity degree ranged from $0.05dSm^{-1}$ to $0.58dSm^{-1}$. The level of soil salinity gradually decreased as it moved farther inland, except the belt I. The level of decreasing soil salinity was found to be in the following order: belt II, belt III, belt I, belt IV. The degree of soil salinity was $EC_{1:5}$ $0.22dSm_{1:5}$, $0.22dSm_{1:5}$ $0.19dSm^{-1}$ and $0.13dSm^{-1}$ respectively. The total 110 taxa, which consisted of 45 families, 74 genus, 101 species, and 9 varieties, were found to be tolerant to both soil salinity and salt spray drift. The trees that grow in the highest degree of salinity($EC_{1:5}$ $0.50dSm^{-1}$)were Parthenocissus tricuspidata(Siebold & Zucc.), Planch and Lonicera japonica Thunb. The next group of trees that grow in the high degree of salinity ranging from $EC_{1:5}$ 0.41 to $0.50dSm^{-1}$ was Cudrania tricuspidata(Carr.) Bureau ex Lavall$\acute{e}$e, Rubus parvifolius L., Zanthoxylum schinifolium(Siebold & Zucc.), Hedera rhombea(Miq.) Bean., Robinia pseudoacacia L., Quercus serrata Thunb., Callicarpa dichotoma(Lour.) K. Koch, and so on. The woody species which grew in the entire belts were Pueraria lobata(Willd.) Ohwi and Vitis flexuosa Thunb., and Vitex rotundifolia L. f. which was known to be highly tolerant to salt spray drift was found only in belt I. The woody species with high important value(IV) were Zelkova serrata(Thunb.) Makino., Celtis sinensis Pers., Koelreuteria paniculata Laxmann, Mallotusjaponicus(Thunb.) Muell. Arg., Trachelospermum asiaticum(Siebold & Zucc.) NAKAI, and Pueraria lobata(Willd.) Ohwi. These species were classified as native windbreak trees that are comparatively more tolerant to salt spray drift than other kinds.

• Korean Journal of Environment and Ecology
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• v.31 no.5
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• pp.444-454
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• 2017

There are many ongoing studies of infectious diseases as the major factor responsible for global declining of the amphibian population. Although some point out the amphibian rearing facilities like frog farms as one of the important sources of harboring and spreading amphibian infectious pathogens in the wild, there have been few related studies in South Korea. In this study, we investigated the bacterial and fungal colonies on the skin and in the internal organs of frogs and tadpoles collected inside and outside of Dybowski's brown frog farms in Inje, Goesan, and Gongju to compare the difference according to the region and between inside and outside the farm. We also intended to classify the bacteria collected from the tadpoles into species by analyzing 16s rDNA gene sequences. The result showed that the number of bacterial colonies found in the skin and gut of frogs and the number of fungal colonies found in the skin and liver of frogs collected in Goesan was significantly greater than those in the frogs in Inje. However, there was no difference between the frogs collected inside and outside of farms in both regions. In the case of tadpoles, the number of fungal colonies in the tadpoles collected from Gongju was greater than that in the tadpoles collected from Inje. The comparison of inside and outside frog farms showed that there were more bacterial colonies on the skin of the tadpoles collected from inside than outside the frog farm in Inje and more bacterial colonies in the organs of the tadpoles collected from outside than inside the farm in Gongju. The frogs with higher condition factor (body weight/snout-vent length*100) showed fewer bacterial colonies on the skin and fewer fungal colonies in the heart, but there were no significant relationships in tadpoles. We identified the total of 15 genera and four phyla of bacteria, but the difference according to regions and between inside and outside farm was not evident. The result of this study indicates that the different conditions according to the locality of farm and between inside and outside farm cause the difference in the population sizes of bacterial and fungal colonies and that it can affect the overall health condition of Dybowski's brown frogs in the farm. Moreover, the result suggests that effective disease control in the facility is greatly necessary to ensure successful operation of amphibian rearing facility and to prevent the possible spread of diseases from the facility to the wild.

• Korea journal of population studies
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• v.26 no.2
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• pp.1-32
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• 2003

An analysis on cause-specific mortality at the provincial level provides essential information for policy formulation and makes it possible to draw hypotheses regarding various diseases and causes of death. Although the mortality level and causes of death at the provincial level are determined by the multiple effects of socioeconomic, cultural, medical and ecological factors, this study primarily intends to examine similarities and differences of cause-specific mortality at the provincial level. Utilizing the registered death and the registered population as of 1998, the delayed death registration and unreported infant deaths were supplemented at the provincial level and age-standardized death rates and life tables were calculated. Regarding the mortality level due to all causes, major findings were as follow: (1) For both sexes as a whole, Seoul showed the lowest mortality level, and Jeonnam showed the highest mortality level; and (2) The differences of the mortality level among provinces were greater for males than females and for those less than 65 years than those 65 years and over. Regarding the cause-specific mortality level revealed in all indicators (cause-specific age-standardized mortality rates and the probability of dying at birth due to a specific cause for males, females, and both sexes combined respectively), the major findings were as follow: (1) The mortality level due to heart diseases was the highest in Busan and the lowest in Gangweon; (2) The mortality level due to liver diseases was the highest in Chonnam; and (3) The mortality level due to traffic accidents was the highest in Chungnam and the lowest in Inchon. As the mortality differentials at the provincial level are related to various factors, exploratory statistical analysis is attempted for the 25 explanatory variables including socioeconomic variables and 90 mortality variables. Mortality due to all causes are related to socioeconomic variables. Among cause-specific mortality, mortality due to liver diseases and traffic accidents is related to socioeconomic variables. Finally, the need to improve the quality of death certificate is discussed.

• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.51-60
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• 1977

In order to determine ecological variations of flowering date and yields under the different seasonal cultures, and to select the higher yielding varieties which were adaptable to Korean climate, 100 mungbean cultivars were sown at the interval of 15 days from April 22 to July 21 in 1976. The results obtained are summarized as follows: 1. The number of days required to flowering from seeding were decreased by delaying the seeding date. 2. When accumulated temperature at first flowering from seeding were reached $945-1,126^{\circ}C$, the mungbean cultivars started to flower regardless of seeding dates. Especially, when mungbean was planted around standard planting date, the plants flowered for very short duration. 3. There were highly significant correlations between the number of days from seeding to flowering at each seeding date and standard planting date. 4. Yields per plant were tend to decrease with the delay of seeding date but there were no significant difference between seeding dates. Therefore, it appears that mungbean can be planted for longer period of time compared to other crops such as rice and soybean. 5. Highly significant correlations were found between the number of days of first flowering and yields per plant at most seeding dates. 6. It may be feasible to grow high yielding mungbean cultivars such as CES 140, LM 2100, LM 690, L 576 and LM 689 after harvesting of spring vegetables in May and before planting of fall vegetables.

• Journal of the Korean association of regional geographers
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• v.5 no.2
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• pp.47-117
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• 1999

This study concern with the pattern of Pusan Station shopping district within Pusan City, Korea, one of the special functioned shopping district within Pusan City. This paper will serve as a part of series studies which attempt to clarify the internal structure of Pusan as a whole. Part(II) of this study deals with the functions including living related, restaurants and others. The pattern of floors, size of shops, street corners and widths of streets were also analysed. The results are as follows: 1. In terms of numbers of firms in living related function, Pusan Station shopping district is the $7{\sim}8th$ ranked central place among nine the highest centers within Pusan City. Pusan Station shopping district has not much promoted vertical spatial differentiation comparatively, and also it's intensity of land use is the lower among nine the highest centers. It is presented that intimate relationship between intensity of vertical land use and classes of central places within the city. The ratio of inns and hotels in Pusan Station shopping district is third ranked in Pusan City. And the size of inns and hotels in this area is the most largest among the nine highest ranked central places within Pusan City. These presented that the traditional characteristics of station area as a special functioned shopping district. Inns and hotels mainly located along the narrower and back street. And it forms agglomerated areas or 'an alley of inns' at the inner parts of blocks, some like a 'hidden flower'. In Korea, 'alley' means that an area of specialization gains the prestige, traditionally. 2. Restaurants mainly locate along the narrower and back streets. And agglomerated areas of restaurants coincide with the agglomerated area of drinking places. It shows that these two kinds of functions need the same locational conditions. The ratio of Chinese restaurants is the highest in the Pusan Station shopping district. It's due to the agglomerated area these kinds of restaurants at the 'China town'. 3. Pusan Station shopping district has been formed along the streets within the residential areas. It's means that this shopping district now at the initial or middle growth era in development stage of shopping areas. 4. In general, wholesales and light manufacturing are located at peripheries within shopping district. But in Pusan Station shopping district, it dose not appear these spatial pattern. It shows that this area is lower ranked central place and not much progressed in spatial differentiation. 5. Particular firms which customers and workers have stayed more longer period of time are located at the far from the first floor. This vertical spatial differentiation is similar to the horizontal sequences. 6. Firms which have more ability of rental payment are located at street comers such as banks and pharmacies. In Pusan Station shopping district commercial facilities could not invade into the second third floors at narrower streets and first floor of back streets, still now.

• Korean Journal of Agricultural and Forest Meteorology
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• v.14 no.4
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• pp.196-206
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• 2012

Studies of seasonal changes in $C_3/C_4$ mixed communities are rare, particularly in Asian summer monsoon climate zones. In our present study, seasonal changes in the profile and coverage of $C_3$ and $C_4$ plants were investigated in 2009 in Haenam, Yeongdong and Cheorwon regions of South Korea (all at different latitudes). The aim was to estimate the impacts of temperature and sunshine duration on species composition and transition timing of the $C_3$ and $C_4$ plants. From our results, the number of $C_3$ plants was found to increase from early spring to mid-May, and then decrease again until September in the Haenam and Yeongdong regions, but continuously increase from early spring to September in the Cheorwon region under relatively low summer temperatures. On the other hand, the number of $C_4$ plants increased from June or July to September in all three regions. These seasonal changes in species number and ratio have a direct impact upon species diversity which is highest when there are no dominant species. The relative coverage and relative summed dominance ratio (SDR') of the $C_3$ plants decreased from spring to autumn, but increased for the $C_4$ plants during this time in an exponential fashion with increasing accumulated temperature and sunshine duration. The transition timing from $C_3$ to $C_4$ plants occurred when the sum of sunshine duration for the days with daily mean temperature above $5^{\circ}C$ was 1017 hrs for the SDR'.

• Korean Journal of Environment and Ecology
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• v.23 no.5
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• pp.431-438
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• 2009

The main purpose of this research is to prepare and provide basic materials for the propagational strategy of eelgrass by investigating on the morphological adaptation of Korean Zostera marina to ocean currents. An eelgrass plant mainly consists of rhizome, leaf sheath, leaves and roots. The rhizome is the horizontal stem of the plant that serves as the backbone from which the leaves and roots emerge. The leaf sheath is the bundle at the base of the leaves that holds the leaves together, protecting the meristem, the primary growth point of the shoot. Leaves originate from a meristem which is protected by a sheath at the actively growing end of the rhizome. As the shoot grows, the rhizome elongates, moving across or within the sediment, forming roots as it progresses. The aggregated leaves from the leaf sheath are found to have two cell layers on one side and multiple layers of airy tissues called aerenchyma on the other. The aerenchyma tissues are developed in multi-layered cell structures surrounding the veins which are formed in the leaf sheath. Generative shoots are made of rhizomes, which are circular or ovoidal, stem, and spathe and spadix. The transverse section of rhizome and the stem and central floral axis is found to be circular, ovoid and in the shape of convex respectively, and the vascular bundle, which is a part of transport system, has one large tube in the center and two small tubes on both sides. The layers of collenchyma cells numbered from 12 to 15 in the stem, and from 7 to 12 in the rhizome. The seed coat is composed of sclereids, small bundles of sclerenchyma tissues, which prevent the influx of sea water from the outside and help endure the environmental stress. In conclusion, alternative multi-layer structure in circular, convex type aggregated leaf base are interpreted to morphological adaption as doing tolerable elastic structure through movement of seawater. The generative shoots develop long slim stem and branches in circular or ovoidal shapes to minimize the adverse impacts of sea current, which can be interpreted as the plant's morphological adaptation to its environment.

• Korean Journal of Environment and Ecology
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• v.32 no.4
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• pp.413-424
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• 2018

The study analyzed the effects of topographic structures and altitude in mountainous parks in Mt. Namsan in Gyeongju on the generation of anions. The temperature was at ridge ($9.82^{\circ}C$) > valley ($8.44^{\circ}C$), the relative humidity valley (59.01 %) > ridge (58.64 %), the solar radiation ridge ($34.40W/m^2$) > valley($14.69W/m^2$), the wind speed ridge (0.63m/s) > valley(0.37m/s), and the negative ion valley($636.81ea/cm^3$) > ridge($580.04ea/cm^3$). In the valley, the correlation with altitude was verified for the temperature, relative humidity, solar radiation, and negative ion generation in the valley. The relative humidity, solar radiation, and negative ion indicated a positive correlation while the temperature had a negative correlation. In the ridge, the correlation with altitude was verified for the temperature, relative humidity, wind speed, solar radiation, and negative ion generation. The relative humidity, solar radiation, and negative ion generation indicated a positive correlation while the temperature and wind speed had a negative correlation. The regression analysis showed the prediction equation of y=-0.006x+9.663 (x=altitude, y=temperature) in the valley and y=-0.009x+11.595 (x=altitude, y=temperature) in the ridge for the temperature, y=0.027x+53.561 (x=altitude, y=relative humidity) in the valley and y=0.008x+56.646 (x=altitude, y=relative humidity) in the ridges for the relative humidity, and y=0.027x+53.561 (x=altitude, y=negative Ion generation) in the valley and y= 0.008x+56.646 (x=altitude, y=negative Ion generation) in the ridge for the negative ion generation.