• 환경위생공학
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• 제8권2호
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• pp.123-148
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• 1993

Over the past-decade of reform and opening up to the outside world, China#s GNP doubled which now ranks eighth in the world, making an average 9.6% increase annually. Some industrial products such as steel, crude oil and power generation rank fourth in the world, while output of coal and cement rank first. In the agricultural sector, China ranks first in the output of grain, cotton, meat and basically solved the problem of providing food and daily necessities for 22% of the world#s population, The Chinese government has set the objectives in environmental protection plan to be achieved by the year 2000 together with ecological protection. During the Seventh Pive-Year Plan(1985-90), Chains#s annual investment in controlling environment pollution was about 10 billion Yuan, or 0.7% of her GNP, while during the Eighth Five-Year Plan, effort will be made to increase such investments, in terms of the GNP, possibly to 0.85"1% . However, the expanding development including industrial production will increase large amounts of pollutants into the environment and efforts are underway to deal with these pollution. *대한위생학회장 Regional community are faced with serious environmental problems. For instance, so called# Yellow Sand Storm# from China is one of the case. Recently, to make matter worse, acid rain and dry depositation from transboundary air pollution is tend to increase mainly because of emissions from mainland China. Therefore, the countries concerned in the region, should seek to promote international cooperation on environmental issues. An overall aspects of development and environmental programs in China are presented.

• 한국물환경학회지
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• 제32권1호
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• pp.15-22
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• 2016

This study aims to analyze the changes in the benthic macroinvertebrate community before and after a restoration project in a eutrophic stream. Species diversity and species richness increased at the points where the channel changed from standing water to running water. However, species diversity and richness decreased at the points where only riparian restoration was implemented, and the concentration of suspended solids increased, while biochemical oxygen demand and total phosphorus decreased and the concentration of dissolved oxygen increased. In such reaches, functional feeding groups went from collector-filterers to collector-gatherers, and habitat orientation groups changed from clingers to burrowers.

• The Korean Journal of Ecology
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• 제18권4호
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• pp.513-513
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• 1995

분리된 자원을 공급한다. 소척추동물과 포식자의 관계에서 동질로화된 서식지는 소척추동물의 생태적 지위를 단일화시켰으며, 숨을 곳의 급격한 감소로 인해 소척추동물의 군집 밀도를 큰 규모로 변동시킨다. 동질화된 서식지는 또한 서식지 구조의 복잡성을 사라지게 함으로써 종의 다양성이 감소된다는 연구결과를 검토하였다. 실험적연구에서 동질화된 서식지는 소척추동물의 서식밀도와 안정성의 감소, 세력권의 증가로 인한 종간경쟁, 분산의 증가로 특징지워졌다. 따라서 서식지의 이질성 유지는 종의 다양성과 보존의 기능을 높여주는데 기여함을 알게 되었다.

• The Korean Journal of Ecology
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• 제18권3호
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• pp.341-351
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• 1995

The relationship between land uses and water quality was investigated at Kyong-an Stream. Some 70% of this watershed was forested area, half of which was comprised of Pinus densilflora community. Concentrations of $NH_4^{+},\;NO_3^{-},\;NO_2^{-}, total nitrogen, $Cl^{-},\;PO_4^{3-}$, DO, and BOD increased gradually from upstream to downstream, whereas heavy metals did not have such tendancy with the exception of a few sites. Urban area was significantly correlated with hardness and chloride concentration. Relationship among phosphate concentration(P), cultivated field area(F), and stream length(S) in each basin was P = 1.7912 F/S＋0.0103. the concentration of $NH_4^{＋}$ was positively correlated with the population size and cow density within the catchment. The effect of urban area(U) and stream length of the pH(pH) was represented by pH = -4.7344 U/S＋6.52. It can be concluded that the control of nonpoint source pollution as well as point source pollution is one of the important problems of water quality management, especially geological properties must be considered for sustainable development.

• The Korean Journal of Ecology
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• 제20권3호
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• pp.157-162
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• 1997

Changes on soil physical and chemical properties following the forest fire in Kosung area in Kangwon province were examined. Twenty seven sampling plots[16 burned (8 low intensity fire, 8 high intensity fire) and 11 unburned plots] from Pinus densiflora community were chosen and soil samples from three depths(0-5, 5-15, 15-25 cm) under the forest floor were collected. Forest fire in the area affected soil chemical properties. Soil pH, available phosphorus, base saturation, K, Ca, and Mg on the surface soil(0-5cm) in the burned areas compared with the unburned areas were increased, while soil properties on the subsurface soil(5-25 cm) were not changed. Organic matter, total nitrogen, available phosphorus, and exchangeable cations following the high in tensity fire on the surface soil were generally lower than those in the low intensity fire areas. This indicates that these nutrients on high intensity fire areas may be volatilized. The results suggest that the fire effects on soil chemical properties were confined mainly to the surface soil and were different between the high and the low intensity fire types.

• Journal of Ecology and Environment
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• 제34권3호
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• pp.323-331
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• 2011

Biodiversity and the community composition of micro-eukaryotic organisms were investigated in the Upo wetland in Korea using molecular analysis. Molecular identification was performed using cytochrome oxidase I (COI) and small subunit ribosomal DNA (SSU rDNA). The genomic DNA was isolated directly from soil samples. The COI and SSU rDNA regions were amplified using universal primers and then sequenced after cloning. In a similarity search of the obtained sequences with BLAST in the Genbank database, the closely related sequences from NCBI were used to identify the amplified sequences. A total of six eukaryotic groups (Annelida, Arthropoda, Rotifera, Chlorophyta, Bacillariophyta, and Stramenopiles) with COI and six groups (Annelida, Arthropoda, Rotifera, Alveolata, Fungi, and Apicomplexa) with SSU rDNA genes were determined in the Upo wetland. Among 38 taxa in 20 genera, which are closely related to the amplified sequences, 10 genera (50%) were newly reported in Korea and five genera (25%) were shown to be distributed in the Upo wetland. This approach is applicable to the development of an efficient method for monitoring biodiversity without traditional taxonomic processes and is expected to produce more accurate results in depositing molecular barcode data in the near future.

• Journal of Ecology and Environment
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• 제34권3호
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• pp.295-305
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• 2011

Many studies have suggested the positive effects of grazing by large herbivorous mammals on seed dispersal, but little is known about how herbivores could affect the fate of ingested seeds. This study examined the effects of seed ingestion by sika deer (Cervus nippon) on seed fate in a temperate grassland established in an urban park long resided by high densities of sika deer. I compared species composition and seasonal traits of seed abundance and maturity in the grassland community with those in deer fecal pellets. In total, 27 herbaceous species were observed, including the predominant Zoysia japonica. Seed phenology and production differed among the three dominant species (Z. japonica, Digitaria violascens, and Hydrocotyle maritima). Pellets contained at least 26 species of herbaceous seeds, and their abundance differed among species. Of the 26 species, 15 were observed in the vegetation at the study site. The peak of seed abundance in pellets for the dominant species appeared 1 month after the peak of inflorescence production (but most of the inflorescences were immature and susceptible to digestion) and consequently corresponded to the peak of mature inflorescence. Because sika deer are likely to ingest seeds at any maturity stage in the grassland and immature seeds are less hardened, ingested immature seeds can suffer great losses. The results suggested that the survival of germable seeds with great losses of immature seeds may be a factor determining which plant species can be successfully dispersed by herbivores.

• Journal of Ecology and Environment
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• 제32권4호
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• pp.221-227
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• 2009

This study describes time lag responses between hydrological variables and phytoplankton biomass in a regulated river system, the lower Nakdong River in South Korea. The lower Nakdong is a typical flow-controlled lotic system, and its limnological characteristics are influenced by climatic variation such as monsoons and summer typhoons. Mean rainfall in the area during summer is about 1,200 mm, which comprises >60% of annual rainfall. Our results show that the regulation of flow in the Nakdong by multi-purpose dams from 1995 to 2004 affected phytoplankton dynamics. Diatom blooms occurred in winter, when the limited discharge allowed for proliferation of the phytoplankton community. Using multiple regression analysis, we detected significant time-delayed relationships between hydrological variables and phytoplankton biomass. These results may be useful for water resource managers, and suggest that 'smart flow' control would improve water quality in large regulated river systems of the Republic of Korea.

• Journal of Ecology and Environment
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• 제33권4호
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• pp.317-323
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• 2010

Nutrient availability is a critical component of agroecosystems, and is relevant to both above- and below- ground interactions. The principal objective of this study was to determine how the cessation of fertilization affects the communities of weeds and soil organisms in a corn/wheat field. Changes in dominant weed species, substrate-induced respiration, and the population density of nematodes and microarthropods were evaluated. Microbial substrate-induced respiration (SIR) and the population density of microarthropods decreased following the cessation of fertilization and were partly correlated with the aboveground weed biomass. The cessation of organic fertilizer application but continuing application of inorganic fertilizer reduced the population density of nematodes. In response to the cessation of fertilization, weed communities were dominated by species with little dependency on fertilization. Amaranthus retroflexus was identified as the most dominant species in the corn field; however, it was replaced by Digitaria ciliaris after the cessation of fertilization. In the wheat field, the cessation of fertilization led to a rapid reduction in the biomass of most weeds, except for Vicia angustifolia, supposedly as the result of symbiotic nitrogen fixation. Additionally, the fact that weed biomass was partially correlated with SIR or the population density of microarthropods may reflect a mutual feedback between soil organisms and weeds. The results indicate that the cessation of fertilization alters communities of weeds and soil organisms through changes in weed biomass and interactions with symbiotic microorganisms.

• 한국환경과학회지
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• 제22권9호
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• pp.1141-1152
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• 2013

Insect fauna were surveyed in 2011 at Ungok wetland, Obeygol, located in Gochang, Jeonbuk, Korea. In total, 149 species belonging to 11 orders and 57 families were surveyed. Among them, Lepidopterans composed 23.5% (35 species) of the total insect numbers surveyed, comprising the most abundant group, and followed by Coleoptera, Hemiptera, and Odonata with a composition of 22.1% (33 species), 17.4% (26 species), and 10.1% (15 species), respectively. Bothrogonia japonica Ishihara was the most dominant species, and followed by Gastrophysa atrocyanea Motschulsky and Celastrina argiolus (Linnaeus). Phytophagous insects accounted for 60 percent of the total species. Dominance index was the highest in spring by 0.21. Diversity, richness, and evenness indices were the highest in summer by 4.07, 11.84 and 0.96, respectively. In the study area, the legally-protect species were grouped into five groups; 9 export-restricted species, 17 endemic species, 28 indicator species, 1 climate-sensitive biological indicator and 3 southern characteristic species. Additionally, twenty forest insect pest species were surveyed, belonging to 5 orders and 15 families. Therefore, it is required to conduct long-term monitoring and appropriate management based on the ecological characteristic of the habitats to continuously conserve and maintain of wetland.