• Korean Journal of Ecology and Environment
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• v.33 no.4 s.92
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• pp.374-379
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• 2000

To elucidate the degradation mechanisms of organic materials in Lake Paldang, oxygen consuming rates in the water column, high molecular weight (HMW) organic materials and aggregates were analyzed. Also the chlorophyll a concentrations and environmental factors were measured three times in 1999. The concentrations of chlorophyll a ranged $5.5{\sim}14.2\;mg/m^3$ with the highest peak of $57.7\;mg/m^3$ at the surface water in April. Chlorophyll a concentration of aggregates retrieved from traps in 5 m and 20 m depths in May were 2779.5, $9044.8\;mg/m^3$, respectively. Those vlaues were more than 6 times higher compared with other months, and more than 49 times higher than water column chlorophyll a. Oxygen consuming rates of water column were in the narrow range of $0.4{\sim}0.5\;mg\;O_2\;l^{-1}\;day^{-1}$. HMW organic materials were using only small amount of oxygen, $0.01{\sim}0.04\;mg\;O_2\;l^{-1}\;day^{-1}$. The aggregates retrieved from 5 m depth by sediment trap consumed the oxygen in the range of $0.48{\sim}0.69\;mg\;O_2\;l^{-1}\;day^{-1}$, while aggregates collected from 20 m depth, 0.88 to $1.04\;mg\;O_2\;l^{-1}\;day^{-1}$. With these results, the HMW appeared not to be degraded in the water column, instead they seemed to be concentrated and affected the sediment oxygen demand.

• Korean Journal of Ecology and Environment
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• v.47 no.1
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• pp.53-61
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• 2014

The origin of particulate organic matter (POM) and food web structure were investigated in Shingu reservoir based on stable isotope analysis from pre-monsoon (July) to post-monsoon (September) 2007. According to the depth in Shingu reservoir, the $^{13}C$ and $^{15}N$ values of POM for pre-monsoon period were nonsignificant distinction, while it was significant variation after rainfall period. The ${\delta}^{13}C$ values of POM in premonsoon period ranged from -25.1‰ to -26.1‰ in whole water column, but the ${\delta}^{13}C$ values of POM in post-monsoon period showed relatively wide range between -23.2‰ and -27.5‰. The apparently lighter values (average -27.5‰) in near bottom water (7 m water depth) demonstrate that POM in high turbid water in post-monsoon period may be derived from the outside terrestrial plants (allochthonous) through heavy rainfall during the summer monsoon period. After rainfall period, $^{13}C$ and $^{15}N$ values of D. brachyurum showed -23.3‰ and 12.2‰, respectively, while B. longirostris showed -27.1% and 8.7%, respectively. It suggested that D. brachyurum mainly feed on POM in autochthonous organic matter pool, but B. longirostris mainly consumed POM in allochthonous organic matter pool after rainfall period. Carbon and nitrogen stable isotope ratios were markedly different among secondary consumers. The carp (C. carpio) and catfish (S. asotus) were in the higher trophic level and crucian carp (C. auratus) and mudfish (M. mizolepis) were in the lower trophic level. $^{13}C$ and $^{15}N$ values of Z. platypus didn't significantly changed between before and after rainfall period. But P. parva and C. auratus apparently changed the $^{13}C$ and $^{15}N$ values after rainfall period. It is suggested that P. parva and C. auratus seem to feed allochthonous food source while Z. platypus depend on autochthonous food source.

• Korean Journal of Ecology and Environment
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• v.49 no.3
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• pp.153-175
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• 2016

Daecheong Reservoir has suffered eutrophication and water-blooms by blue-green algae from initial impoundment, and algae alert system (AAS) was introduced in 1997. The purpose of this study was to investigate the effect of rainfall and hydrological factors in increase or decrease variability of green-tide and prolonged AAS, studied and analyzed the current situation of AAS has been operating for 19 years (1997~2015) in Daecheong Reservoir. The total issued number of AAS was 46 times, the most frequent period in August and September were 22 times (752 days) and 16 times (431 days), respectively, it accounted for 82.6%. Many number and frequency during this period were significantly associated with rainfall, various discharge and water level. Rainfall and hydrological events are associated with the rainy season of monsoon-Changma and the typhoon, it was concentrated in June~September, total rainfall in this period accounted for 69.9% of the annual rainfall. An increase in inflows was dependent on the intensity, frequency and the amount of rainfall. Accounted for 68.4% of the total annual inflow, it was a time when the most rapidly changing hydrological variability in the reservoir. The total outflow was closely related to rainfall, and compared the distinctive characteristics of hydropower generation and watergate-spillway discharge. In addition, the upreservoir zone of Daecheong Reservoir could be vulnerable to green-tide by regulating discharge of the upstream dam. The issue of AAS was strongly related to the with and without of watergate-spillway discharge. The watergate-spillway discharge had a total of 25 times, it was maximum 17 days from July to September in the year. And the opening times and each duration of the watergate were 1~4 times and the range of 3~37 days, respectively. When the watergate opened, the issue of AAS was maintained to 13 years and the movement of water bodies and green-tide was great about five times than that of non-open, had a profound effect on prolonged AAS within reservoir. In Daecheong Reservoir, Chusori (CHU) area of the So-ok Stream was still showing serious symptoms green-tide levels in the summer, but Janggye (JAN) waters of the main reservoir was pointed out that more important. AAS will be operated by an absolutely consider the rainfall and hydrological effects around the watergate-spillway discharge. The measures of green-tide will be included in the limnological studies more suited to the characteristics of the watershed and reservoir of the our country. Finally, from now on, we will prepare the systematic management and guidelines for vulnerable zone water-blooms that are the source within the reservoir before the monsoon rather than waiting for the arrival of green-tide on the operating stations of AAS.

• Journal of Environmental Policy
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• v.4 no.2
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• pp.31-55
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• 2005

Dangsan forests and Rural Community Forests(RCF) have been historical assets for the rural communities of more than 40,000 in Korea and they have provided an identity through the cultural heritage. The Dangsan forests and the RCF are parts of a unique cultural landscape in the rural areas as components of stream landscape. In many cases, the Dangsan forests and the RCF are located close to stream corridors. The objective of this study was to understand the function of the Dangsan forests and the RCF on stream water quality and to evaluate its ecological landscape values. Through the consideration of international concensus and domestic government policy for close-to-nature stream, we could find out that Dangsan forests and RCF's have close relationship with the close-to-nature streams. The water quality of the streams close to the Dangsan forests and the RCF are maintained with local culture. It is also compared to the streams located where Dangsan forests and the RCF are absent. Eight study sites were selected. Water samples were collected at three different locations at each study site. Water samples were analyzed for temperature, pH, total P, total N, dissolved oxygen, EC, BOD, COD and SS. Aquatic invertebrates were observed as water quality indicator species. The results showed that the number of aquatic invertebrate species, GPI, DO, EC, BOD, and SS were significantly improved in stream water due to the presence of the Dangsan forests and the RCF. The role of Dangsan forests and the RCF was evident in the conservation of stream landscape and rural culture as well as in maintaining stream water quality. The management schemes of the streams with Dangsan forests and the RCF's are also suggested.

• Journal of Wetlands Research
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• v.22 no.2
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• pp.81-91
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• 2020

As part of method for ecologically utilizing abandoned paddy, potential of the abandoned paddy as a target site for ex-situ conservation of 9 endangered species of different life form was confirmed by considering the nature of rice paddy. In order to create Dum-bung, a component of traditional Korean rice paddy, a part of the abandoned paddy was modified to change the water environment. The seeds, asexual reproductive and sexually reproductive individuals of each endangerd species were transplanted into the abandoned paddy to observe the survival rate and phenological response for 1 year, and then monitored for 2 years. As a result, Hydrophyte 4 taxa (Euryale ferox, Saururus chinensis, Dysophylla yatabeana, Menyanthes trifoliata), Geophyte taxa 1 (Epilobium hirsutum), and Hemicryptophyte taxa 1 (Cicuta virosa) could be introduced into the abandoned paddy. In particular, Euryale ferox, Dysophylla yatabeana, and Menyanthes trifoliata should be introduced into Dum-bung, and Saururus chinensis, Epilobium hirsutum, and Cicuta virosa should be introduced into paddy wetland. Growth of Euryale ferox and Brasenia schreberi was inhibited by herbaceous species, and the growth of Epilobium hirsutum was inhibited by herbivores. Therefore, in order to help efficient settlement of endangered plants introduced in abandoned paddy, it is necessary to remove herbs that inhibit growth and to manage herbivores. In addition, it is necessary to prevent the collapse of paddy bank by planting on the paddy field trees or herbaceous forming vegetation mat. When using abandoned paddy ecologically, it is effective to diversify the moisture environment by creating a Dum-bung to increase biodiversity.

• Journal of Distribution Science
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• v.10 no.7
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• pp.33-41
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• 2012

The purpose of this study is to analyse the state of the energy industry and to determine the efficiency of its functioning on the basis of energy conservation principle and application of innovative technologies aimed at improving the ecological modernisation of agricultural sectors of Kazakhstan. The research methodology is based on an integrated approach of financial and economic evaluation of the effectiveness of the investment project, based on calculation of elasticity, total costs and profitability, as well as on comparative, graphical and system analysis. The current stage is characterised by widely spread restructuring processes of electric power industry in many countries through introduction of new technical installations of energy facilities and increased government regulation in order to enhance the competitive advantage of electricity market. Electric power industry features a considerable value of creating areas. For example, by providing scientific and technical progress, it crucially affects not only the development but also the territorial organisation of productive forces, first of all the industry. In modern life, more than 90% of electricity and heat is obtained by Kazakhstan's economy by consuming non-renewable energy resources: different types of coal, oil shale, oil, natural gas and peat. Therefore, it is significant to ensure energy security, as the country faces a rapid fall back to mono-gas structure of fuel and energy balance. However, energy resources in Kazakhstan are spread very unevenly. Its main supplies are concentrated in northern and central parts of the republic, and the majority of consumers of electrical power live in the southern and western areas of the country. However, energy plays an important role in the economy of industrial production and to a large extent determines the level of competitive advantage, which is a promising condition for implementation of energy-saving and environmentally friendly technologies. In these circumstances, issues of modernisation and reforms of this sector in Kazakhstan gain more and more importance, which can be seen in the example of economically sustainable solutions of a large local monopoly company, significant savings in capital investment and efficiency of implementation of an investment project. A major disadvantage of development of electricity distribution companies is the prevalence of very high moral and physical amortisation of equipment, reaching almost 70-80%, which significantly increases the operating costs. For example, while an investment of 12 billion tenge was planned in 2009 in this branch, in 2012 it is planned to invest more than 17 billion. Obviously, despite the absolute increase, the rate of investment is still quite low, as the total demand in this area is at least more than 250 billion tenge. In addition, industrial infrastructure, including the objects of Kazakhstan electric power industry, have a tangible adverse impact on the environment. Thus, since there is a large number of various power projects that are sources of electromagnetic radiation, the environment is deteriorated. Hence, there is a need to optimise the efficiency of the organisation and management of production activities of energy companies, to create and implement new technologies, to ensure safe production and provide solutions to various environmental aspects. These are key strategic factors to ensure success of the modern energy sector of Kazakhstan. The contribution of authors in developing the scope of this subject is explained by the fact that there was not enough research in the energy sector, especially in the view of ecological modernisation. This work differs from similar works in Kazakhstan in the way that the proposed method of investment project calculation takes into account the time factor, which compares the current and future value of profit from the implementation of innovative equipment that helps to bring it to actual practise. The feasibility of writing this article lies in the need of forming a public policy in the industrial sector, including optimising the structure of energy disbursing rate, which complies with the terms of future modernised development of the domestic energy sector.

• Journal of Life Science
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• v.30 no.4
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• pp.331-342
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• 2020

The suppression of neuroinflammatory responses in microglial cells can be considered a key target for improving the progression of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease (PD), and Huntington's disease (HD). Asparagus cochinchinensis has traditionally been used as a medicine to treat fever, cough, kidney disease, breast cancer, inflammatory diseases, and brain diseases. In this study, we investigated the neuroprotective mechanism of an aqueous extract from A. cochinchinensis root (AEAC), particularly its anti-inflammatory effects on lipopolysaccharide (LPS)-activated BV-2 microglial cells. BV-2 cells were treated with four different concentrations of AEAC. No significant toxicity was detected in BV-2 cells treated with AEAC. Nitric oxide (NO), cyclooxygenase-2 (COX-2) mRNA, and inducible nitric oxide synthase (iNOS) mRNA levels were 21% lower in the AEAC+LPS group than in the Vehicle+LPS group. Lower proinflammatory (TNF-α and IL-1β) and anti-inflammatory cytokine (IL-6 and IL-10) levels were also detected in the AEAC+LPS group than in the Vehicle+LPS group, albeit at varying rates. Moreover, the phosphorylation of mitogen-activated protein kinase (MAPK) members after LPS treatment was significantly recovered in the AEAC-pretreated group compared to the Vehicle+LPS group, enhancement of the phosphorylation of mitogen-activated protein kinase (MAPK) members after LPS treatment was significantly recovered in the AEAC-pretreated group, while cell cycle arrest at the G2/M phase caused by LPS treatment was less severe in the AEAC+LPS group. The increase in reactive oxygen species (ROS) generation induced by LPS treatment was also lower in the AEAC-pretreated group than in the Vehicle+LPS group. This is the first study to show that AEAC exerts anti-neuroinflammatory activity against LPS stimulation by regulating the MAPK signaling pathway, the cell cycle, and ROS production.

• Korean Journal of Ecology and Environment
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• v.48 no.4
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• pp.253-262
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• 2015

The sustainability of Cypripedium japonicum, a rare plant designated by the Korea Forest Service, is threatened due to artificial factors such as habitat loss and climate change etc. and internal factors such as changes in biological properties of the habitat etc. but conservation research has not been performed in South Korea. The objective of this study is to establish the species conservation strategies by analyzing the characteristics of their habitats, including: 1) Population characteristics, and 2) habitat analysis of the vegetation and abiotic environments. From April to September, 2014, population characteristics [density (stems $m^{-2}$), flowering rate (%), and leaf area ($cm^2$)] in Cypripedium japonicum habitats such as Chuncheon (CC), Hwacheon (HC), Muju (MJ), and Gwangyang (GY) and vegetation characteristics (plant sociological research and ordination analysis), and abiotic environments [temperature ($^{\circ}C$), relative humidity (%), transmitted light ($mol{\cdot}m^{-2}{\cdot}d^{-1}$) and canopy openness (%)] were measured. Cypripedium japonicum was mainly distributed at elevation 450 to 990 m and 5 to $30^{\circ}$ slope. Slope direction was shown as 0 to $110^{\circ}$. Habitats temperature (mean $18.94^{\circ}C$) was well matched to seasonal changes. Differences among sites showed greater level according to latitude difference. It showed the highest in habitat, GY located in the South. On the other hand, relative humidity (77.38%) didn't show much difference among sites. The average degree of canopy openness was 18.17%. It showed the highest at HC (22.1%) and the lowest at MJ (16.1%). The average degree of transmitted light was $9.1mol{\cdot}m^{-2}{\cdot}d^{-1}$. It showed the highest at CC ($10.6mol{\cdot}m^{-2}{\cdot}d^{-1}$) and the lowest at GY ($6.87mol{\cdot}m^{-2}{\cdot}d^{-1}$). Chlorophyll content showed average 26.12 SPAD. It showed the highest at MJ (30.64 SPAD value) and the lowest at HC (23.69 SPAD value). Leaf area was average $253.35cm^2$. It showed the highest at CC ($281.51cm^2$) and the lowest at HC ($238.23cm^2$).

• Korean Journal of Ecology and Environment
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• v.44 no.4
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• pp.396-406
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• 2011

To analyze between water quality and community structure of benthic macroinvertebrates, we selected four reservoirs (Lake Sayeon, Lake Daeam, Seonam reservoir and Lake Hoeya) in Ulsan-si and studied them from February 2010 to October 2010. The annual mean BOD (Biochemical Oxygen Demand) in the four lakes was $14.2mg\;L^{-1}$, and Seonam reservoir had the highest deviation in BOD. The maximum BOD for every lake was in February and their minimum in May, except for Lake Hoeya whose minimum was in July. The means of various nutrients were as follows: TN $0.051mg\;L^{-1}$, TP $0.100mg\;L^{-1}$, $NH_3-N\;0.606mg\;L^{-1}$, and $NO_3-N\;0.014mg\;L^{-1}$. The maximum TN was measured in June and the maximum and minimum TP were measured in March and in May respectively in the four lakes. Benthic macroinvertebrates were surveyed in April and October 2010. The number of benthic macroinvertebrates species was in the range of 16~36 and the average number of individuals were 58~208 inds. $m^{-2}$. Seonam reservoir, which has the highest mean TN ($0.082mg\;L^{-1}$) and $NO_3-N$($0.023mg\;L^{-1}$), had the largest number of species (36 species, 208 inds. $m^{-2}$). Pearson's correlation between the number of macro invertebrates species and TN was 0.962 (P<0.05), and between the species and $NO_3-N$ was 0.999 (P<0.05). These results show that the number of benthic macroinvertebrates species of the four lakes in Ulsan-si is significantly correlated with TN and $NO_3-N$.

• Korean Journal of Ecology and Environment
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• v.46 no.3
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• pp.332-342
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• 2013

We collected zooplankton from May to October, 2011, with the aim of understanding the zooplankton community distribution and food web interaction between the open water and littoral (aquatic plants) zones in two small reservoirs with different land covers (Sobudang, Myeongdong). Small-sized reservoirs are more abundant in South Korea, and a total of 51 and 65 species of zooplankton were identified at the two small reservoir (Sobudang and Myeongdong), where zooplankton densities were more abundant in the littoral zone than in the open water zone. Cladocerans and copepods densities were also higher in the littoral zone, in contrast, rotifers showed higher densities in the open water zone (t-test, P/0.05). Epiphytic zooplankton dominated at the littoral zone (Lecane, Monostyla, Alona and Chydorus) because aquatic plants provided refuge spaces for attachment. Some rotifers (e.g. Brachionus, Keratella and Polyarthra) were more abundant in the open water zone because of their small size, which might help them to go unnoticed by predators. In two-way ANOVA, rotifers related to two reservoirs or habitat space (littoral zone and open water zone), but cladocerans and copepods showed a statistically significant relationship on only two reservoirs. The results of stable isotope analysis showed that zooplankton in the littoral zone tended to depend on organic matter attached to aquatic plants as a food source, which indicates the avoidance of competition of zooplankton with other macro-invertebrates (e.g. Damselfly larva, Cybister brevis and Neocardina denticulate). As a result, zooplankton community distribution is determined by not only habitat space (aquatic plant zone and open water zone) but also by food source (phytoplankton).