• Journal of Environmental Science International
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• v.17 no.8
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• pp.841-856
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• 2008

This research outlines a new method for evaluation of shellfish production in Gamak Bay based on the concept of EMERGY. Better understanding of those environmental factors influencing oyster production and the management of oyster stocks requires the ability to assess the real value of environmental sources such as solar energy, river, tide, wave, wind, and other physical mechanisms. In this research, EMERGY flows from environment sources were 76% for shellfish aquaculture in Gamak Bay. EMERGY yield ratio, Environmental Loading Ratio, and Sustainability Index were 4.26, 0.31 and 13.89, respectively. Using the Emergy evaluation data, the predicted maximum shellfish aquaculture production in Gamak Bay and the FDA (Food and Drug Administration, U.S.) designated area in Gamak Bay were 10,845 ton/y and 7,548 ton/yr, respectively. Since the predicted shellfish production was approximately 1.3 times more than produced shellfish production in 2005, the carrying capacity of Gamak Bay is estimated to be 1.3 times more than the present oyster production.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.465-475
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• 2001

Based on the community structural attributes, such as species composition, diameter and height distribution, topographic position, and species diversity in the natural deciduous forest of Mt. Gari area, this study suggested desirable species and composition ratio to achieve ecological management of forests so as to maintain forest stability and enhance economical values. The results are as follows : 1. Twenty-five tree species were growing in the study forest. Of these Quercus mongolica, Pinus densiflora, Juglans mandshurica, Quercus serrata, Cornus controversa, Acer mono, Fraxinus rhynchophylla, and Tilia mandshurica were selected for desirable species through the evaluation of dominant and dominant potential. Kalopanax pictus, considered to be highly valuable species, was also included. 2. Taking account of different species composition pattern by topographic positions, we select as desirable species of J. mandshurica, C. controversa, Q. mongolica, A. mono, T. mandshurica, and F. rhynchophylla in the valley area, Q. mongolica, Q. serrata, A. mono, T. mandshurica, F. rhynchophylla, and K. pictus in the mid-slope area, and Q. mongolica, P. densiflora, Q. serrata, and Fraxinus rhynchophylla in the ridge area. 3. Based on the estimation of species diversity index for the overstory components, the reasonable forest stability levels of the indices were estimated at 1.96, 1.68, 1.94, and 1.27 for whole forest, valley, midslope, and ridge, respectively. 4. The recommended species composition ratios in the study forest were suggested Q. mongolica to be 30%, A. mono, F. rhynchophylla, Q. serrata, and T. mandshurica to be 10%~15%, J. mandshurica, P. densiflora, and C. controversa to be 5%~10%, and K. pictus to be 5%.

• Journal of Korean Society of Forest Science
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• v.79 no.2
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• pp.115-126
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• 1990

This study was performed to find differences in phototaxis response of the larva, adult emergence, sex ratio and gall formation rate of Thecodiplosis japonensis Uchida et Inouye between two areas, north and south. Larvae from these two areas, Hweng-sung in north and Moo-an in south, both considered to be the sities of severe outbreak of the insect recently, were collected from the floor and transported to the entomology larboratory, Won-Kwang University in Iri, then overwintered. These larvae were used for various experimental purposes on various dates. The following results were obtained. 1. The sizes of larvae reached 2.45 in length, 0.70 in width for north, and 2.50 in length, 0.72 in width for sourth. It seems that the differents were not significant. 2. It is known that Leaving gall of larvae to the ground for the hibernation usually occurs on rainy days. For the larvae dispersion, the phototaxis response of the larvae was hypothesized. To check this, the author manipulated some different illumination intensities adjusting the distance between the glass tube in which 100 larvae were contained and electric bulb. The glass tubes were blackened all but except a small portion. The phototaxis responses between two areas seemed to be different particularly at low light intensities, 45, 145 and 1000 lux, The larvae from north assembled to the clear portion of the glass tube were more than 30 out of 100, however less than 30 in south sample regardless of the time passage. In either cases, the saturation points came after about 8 to 10 hours. If temperature units were used, the phototaxis curve= after 1 hour illumination between two areas provided significant differences. 3. The adult emergence of south area was lagged 10 days later than that of north area. The accumulated effective day-degrees of temperature for adult emergence were $934^{\circ}C$ for north area and $1180^{\circ}C$ for south area. The emerging duration of north area appeared to be in late May through the early of July and the peak emergence occurred in middle June that was approximately 15days earlier than that of south area. The sex ratio of female to male, regardless of area, was approximately 3 : 1. 4. The rates of gall formation of the red pine(Pinus densiflora Siebold et Zuccarini), 6-year-old seedlings, were as low as 9.94% for north area and 8.87% for south area. Through the close observation, the author presumed that the population reduction was greatly affected during the prepupa stage by relative moisture content and predators, such as spiders and ants presented on the ground.

• The Korean Journal of Ecology
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• v.10 no.1
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• pp.7-16
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• 1987

The content of Pb and Cd in the soil, producer, 1st consumer and 2nd consumer by the distance from two highway with different construction years and traffic volumes was measured from 1984 through 1986. The result was compared with that of a control in Yangsu-ri near Mt. Unak, Namyangju-gun, Kyunggi-do. The producers in the area of Yangjae-done are composed of 27 species of floras with Glycine soja being the dominant species while those in Shingal 20 species, with Leesia japonica being the dominant species. The faunas in the former area include 37 families and 69 species, with insects being dominant. In the area of Yangjae-dong, the biomass by trophic levels increased from the ration of 1/400 between producer and 1st consumer to the ratio of 1/10 between 1st consumer and 2nd consumer. The Pb content of soil, producer, 1st consumer and 2nd consumer in Yangjae-done near the Kyungbu highway with traffic jam has the sigingacant difference of 1% level at the vicinity of 10 meters and it is the same with that of Shingal area nearthe Youngdong highway with relatively sparse traffic except for the 2nd consumer. In case of cadmium content, the 1st and 2nd consumer has 1% signigicant difference near the Kyungbu highway and other trophic levels have no diference. Besides, the content of Pb and Cd at the site 1, 2 and 3 within the range of 100 meters from the two highways has 1% significant difference from that of a control while the site 4 has no difference.

• Journal of the Korean Geographical Society
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• v.28 no.3
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• pp.213-226
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• 1993

In Korea, the urban studies of geography have mainly dealt with such a series of research as system of urban place and internal structure of urban area. The existing studies have been carried out with ecological approach. Ecologists, now a days, regard organiation and transfor-mation of the urban space as the process of invasion, succession, and segregation. However it is more proper that cities should be considered not as fragmantary objects, as some ecologists insist, but as synthetic ones in social structure. This research, with adopting a case of the renewasl of central area in Seoul, tried to make it clear that the formation and transition of the city is a product of social structure and examined polical and economic logic which exists in variation of urban space in detail. The results of this study are as follows; Urban renewal of central area is closely related with production and reproduction in capitalist society. In urban center, as business activities had increased since 1973 due to decen-tralization of production process, the necessity of reorganizing the land use in existing central area accordingly increased. The urban renewal program of central area in Seoul was inrroduced under such situation. The urban renewal of central area reflecting the capital logic has changed the central area with six hundred year's tradition. From the urban renewal of central area, not only was the central area, which traditionally had been mixed with various fun-ctions, simplified into the unitary area of busi-ness, but also physical landscape changed. As the land lot in renewal area expanded into regular shape, buildings became larger and taller. The program tremendously raised the price of related area. Aiming at these profits caused by the raised price, a great number of capitalists participated in the program. And as the benefit ratio of the manufacture sector continuously dropped with the economic recession, the pro-gram was carried out much more vigorously. That was because the idle capital accumulated during the recession was invested in property sector and was self-proliferated. The urban renewal raised the land value of central area and drove out the people living in this area. The people moved into the whole parts of the city resulting diffused squatter settlements. And the urban changes in central area were results of the policy of municipal authorities, who supported and systematized the changes lawfully and administratively, as well as reali-zation of capital logic. Due to the renewal policies of central area in Seoul, much more renewals by the only capitalists were carried out than those by the people themselves living in that area. The integration of land ownership in the law of urban renewal shows the reason of that. Moreover, the law allows the third deve-loper to participate in the tasks and admits the land expropriation rights. The municipal autho-rities guaranteed the profitability of the tasks through finacial aid, tax benifit, and relaxation of regulations for construction. As examined above, the changes in the land use of urban space have been led not by the ecological process of development of the city itself, but by the restructuring of capitalism and the intervention of the government authorities.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.20 no.4
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• pp.1-13
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• 2017

The purpose of this study is to analyze a term of decade of water quality data of the Mulgum intake station on the Nakdong river(dam) to find the cause of algal blooms and to set an alternative to prevent artificial lake water pollution. Our study shows that water quality changes have regular periodic regularity and there was a certain correlation between specific analytical items. According to the analysis results of each factor, the decline in precipitation was not the main reason for algal blooms. TP concentration had a slight effect on Chl-a concentration but was not a limiting nutrient of a bloom. TN concentration had a strong correlation with Chl-a and strongly negative correlation with temperature, but was not a bloom's limiting nutrient, and was only a dependent variable. As the temperature was negatively correlated with the Chl-a concentration, it is found that the aspect of the ecological influence of the temperature was the most important factor of the phytoplankton concentration change. The N/P ratio lies under a power function with a high degree of reliability by the TP concentration, and the phenomenon appeared to be the same as the results of two other comparative areas. This result confirms that TN is dependent on TP and the biota in the lake that TN is a dependent variable whose concentration is determined by TP it. In conclusion, the increase in lake bloom is the result of a food chain change, and it is necessary to control the ecosystem by the food chain in the lake in order to reduce the lake's bloom. In particular, it is important to keep the benthic ecosystem as wide as possible in the aerobic state.

• Journal of Environmental Impact Assessment
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• v.24 no.1
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• pp.51-65
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• 2015

The flora distributed around Mt. Hwangseok were summarized as 495 taxa including 97 families, 295 genera, 394 species, 4 subspecies, 80 varieties and 17 forms. In the component ratio of taxa, pteridophyta was 4.2%, 1.2% of gymnospermae, 78.8% of dicotyledonae and 15.8% of monocotyledonae. The rare plants were 9 taxa including Aconitum chiisanense, Eranthis stellata, Aristolochia contorta, Viola albida and so forth. The Korean endemic plants were 13 taxa including Populus tomentiglandulos, Pseudostellaria coreana, Aconitum pseudolaeve, Thalictrum actaefolium var. brevistylum and so forth. The specific plants by floristic region were 16 taxa including Cimicifuga heracleifolia, Sanguisorba longifolia, Symplocarpus renifolius, Betula davurica and so forth. The plants adaptable to climate change were 11 taxa including Aconitum pseudolaeve, Ajuga spectabilis, Carex okamotoi, Rhynchosia volubilis and so forth. The naturalized plants were 20 taxa including Fallopia convolvulus, Rumex crispus, Phytolacca amrericana, Robinia pseudoacacia and so forth. The invasive alien plant was Aster pilosus. The emergence of local ecologically important species, set the correct range for the core and buffer zone, transition zone, coded will be necessary, the distribution of the specialty plant areas and rare plants, an area management plan should be organized by nature. In addition, a variety of assessment techniques and accurate data to establish the validity of the core area is also set to acquire.

• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.4
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• pp.392-402
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• 2020

We investigated the concentrations of acid volatile sulfide (AVS), ignition loss (IL), total organic carbon (TOC), total nitrogen (TN), and metallic elements (As, Cd, Cr, Cu, Fe, Hg, Mn, Pb, and Zn), in August 2015, to determine the spatial distribution and pollution status of organic matter and metals in the surface sediment of Jinju Bay, a spraying shellfish farming area, Korea. The concentrations of organic matter and metallic elements were significantly higher in the southern part of the bay than in the mouth and center of the bay. The C/N ratio (5.7~8.0) in the sediment represents the dominance of organic matter of oceanic origin in the surface sediment of the study area. The concentrations of AVS, TOC, and metals (As, Cd, Cr, Cu, Hg, Pb, and Zn) were much lower than the values of the sediment quality guidelines applied in Korea. Based on the results of the pollution load index (PLI) and ecological risk index (ERI), the metal concentrations in the surface sediment of Jinju Bay have a weakly negative ecological effect on benthic organisms although the sediments with high metal pollution status are distributed in the southern parts of the bay, with high dense shellfish farming areas. Thus, the surface sediments in Jinju Bay are not polluted with organic matter and are slightly polluted with metallic elements.

• The Korean Journal of Ecology
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• v.20 no.5
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• pp.385-391
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• 1997

To investigate the degrees of toxification in the serpentine areas, serpentinites and adjacent metamorphic rocks and soils from the serpentinite, metamorphic area and transitional area(mixed soil) between serpentinite and metamorphic rocks are collected from the Hongseong-Gun, Chungnam. A plant, Geochemically, the serpentinites are high in the nickel, chromium and cobalt content whereas the metamorphic rocks show high zinc, scandium, molybdenum and iron contents. The serpentine soils are high in the nickel, chromium and cobalt contents whereas the non-serpentine soils show high zinc and iron contents. Heavy metal contents in the G. oldhamiana are high in the serpentine soil relative to the mixed soil. Ratio of the iron to nickel contents for the G. oldhamiana are low in the serpentine soil(49) relative to the mixed soil(216). Of the G. oldhamiana, most of the heavy metal contents except zinc and molybdenum are high in the root relative to the aboveground vegetation. Comparing with rocks, the G. oldhamiana is low in the all of heavy metal contents relative to the serpentinite. Uptake of zinc by the G. oldhamiana is high in the serpentinites and metamorphic rocks whereas uptake of scandium and iron by the G. oldhamiana is very high in the serpentinite area.

• The Korean Journal of Ecology
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• v.12 no.2
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• pp.83-108
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• 1989

To discern general tendency in relatively pure even-aged pine stands, to group the stands and to perceive neighbourhood effects a total of 39 sites of pine stand was surveyed from nearby Seoul (12 sites), Chunsung, Kangwon (13 sites) and Sosan, Chungnam (14 sites), for herb and shrub species 32, 19; 37, 19 and 41, 14 in the respective areas from September 1987 to July 1988. In terms of detrended correspondence analysis (DECORANA), the stands were subjected to ordinate with 16 physical variables and the vegetational variables. The resource ratio (N:P, N:K, P:K) as physical variables also was tried out in the DECORANA as well as independent variable (N.P.K). The outcome did not show any meaningful difference. It is suggested that there seems to be no apparent interaction among the elements in the study. Three vertical vegetation componeent, that is, tree layer, shrub layer, herb layer were subjccted to DECORANA independently, pairwisely and as a whole (a total 7 combinations). Of those analysis herb layer trial alone seems to indicate relatively clearer differences among the physical variables. In the stands nearby Seoul first axis indicated soil field capacity and exchangeable cations (K, Ca and Na) and second axis did not show any tendency. For the Chunsung stands first axis also revealed soil field capcity and amount of arganic matter and second axis showed amount of exchangeable cation (K, Ca and Na), In the Seosan 1st axis indicated pH and exchangeable cations (K, Ca and Na). For the 39 sites 4 clusters in terms of herb layer might be defined: Peucedanum terebinthaceum-Cymbopogon tortilis-Polygala japonica-Festuca ovina (1); Atractylodes japonica-Patrina scabiosaefolia (2); Potentilla fragarioides-Atractylodes (3); and Cymbopogon tortilis (4). In the neighbourhood effects study in terms of the basal area distribution, Thiessen polygon area and Gini coefficient for the Pinus thunbergii stands of Seosan the Thiessen polygon area approach seems to indicate earlier (30 years old) neighbourhood effect than the others (45 years).