• Title/Summary/Keyword: Community engineering

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A Study on the Characteristics and Management Plan of Old Big Trees in the Sacred Natural Sites of Handan City, China (중국 한단시 자연성지 내 노거수의 특성과 관리방안)

  • Xi, Su-Ting;Shin, Hyun-Sil
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.41 no.2
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    • pp.35-45
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    • 2023
  • First, The spatial distribution characteristics of old big trees were analyzed using ArcGIS figures by combining basic information such as species and ages of old big trees in Handan City, which were compiled by the local bureau of landscaping. The types of species, distribution by ages of trees, ownership status, growth status, and diversity status were comprehensively analyzed. Statistically, Styphnolobium, Acacia, Gleditsia, and Albizia of Fabaceae accounted for the majority, of which Sophora japonica accounted for the highest proportion. Sophora japonica is widely and intensively distributed to each prefecture and district in Handan city. According to the age and distribution, the old big trees over 1000 years old were mainly Sophora japonica, Zelkova serrata, Juniperus chinensis, Morus australis Koidz., Dalbergia hupeana Hance, Ceratonia siliqua L., and Pistacia chinensis, and Platycladus orientalis. Second, as found in each type of old big tree status, various types of old big tree status were investigated, the protection management system, protection management process, and protection management benefits were studied, and the protection of old big tree was closely related to the growth environment. Currently, the main driving force behind the protection of old big trees is the worship of old big trees. By depositing its sacredness to the old big tree and sublimating the natural character that nature gave to the old big tree into a guiding consciousness of social activities, nature's "beauty" and personality's "goodness" are well combined. The protection state of the old big tree is closely related to the degree of interaction with the surrounding environment and the participation of various cultures and subjects. In the process of continuously interacting with the surrounding environment during the long-term growth of old big trees, it seems that a natural sanctuary was formed around old big trees in the process of voluntarily establishing a "natural-cultural-scape" system involving bottom-up and top-down cross-regions, multicultural and multi-subjects. Third, China focused on protecting and recovering old big trees, but the protection management system is poor due to a lack of comprehensive consideration of historical and cultural values, plant diversity significance, and social values of old big trees in the management process. Three indicators of space's regional characteristics, property and protection characteristics, and value characteristics can be found in the evaluation of the natural characteristics of old giant trees, which are highly valuable in terms of traditional consciousness management, resource protection practice, faith system construction, and realization of life community values. A systematic management system should be supported as to whether they can be protected and developed for a long time. Fourth, as the perception of protected areas is not yet mature in China, "natural sanctuary" should be treated as an important research content in the process of establishing a nature reserve system. The form of natural sanctuary management, which focuses on bottom-up community participation, is a strong supplement to the current type of top-down nature reserve management in China. Based on this, the protection of old giant trees should be included in the form of a nature reserve called a natural monument in the nature reserve system. In addition, residents of the area around the nature reserve should be one of the main agents of biodiversity conservation.

The Limnological Survey of a Coastal Lagoon in Korea (2): Lake Hyangho (동해안 석호의 육수학적 조사(2): 향호)

  • Kwon, Sang-Yong;Lee, Jae-Il;Kim, Dong-Jin;Kim, Bom-Chul;Heo, Woo-Myung
    • Korean Journal of Ecology and Environment
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    • v.37 no.1 s.106
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    • pp.1-11
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    • 2004
  • The limnological characteristics of a coastal lagoon were studied in Lake Hyangho, one of a series of brackish lagoons along the eastern coast of Korea. Phytoplankton community structure, physical factors, and chemical factors were surveyed from May 1998 through November 2002 on a two-month interval basis. Temperature, salinity, Secchi disc transparency, TN, TP, organic matter content of sediment, chlorophyll a concentration, dominant phytoplankton species, and phytoplankton cell density were measured. Salinity gradient was formed between the overlying freshwater stream water and the permeated seawater at the bottom. The chemocline was persistent at the depth of 2 ${\sim}$ 5 m that caused discontinuities of salinity, DO, and temperature profiles. The inversion of vertical temperature profiles with higher temperature in deeper layer was observed in early winter. Secchi disc transparency was very low with the range of 0.1 to 1.1m. TP, TN, and Chl. a concentration in the epilimnion was 0.011 ${\sim}$ 0.238 mgP $L^{-l}$, 0.423 ${\sim}$ 2.443 mgN $L^{-l}$, and 0.7 ${\sim}$ 145.2 mg $m^{-3}$, respectively. Sediment was composed of silt and coarse silt. COD, TP, and TN content of dry sediment were 19.7 ${\sim}$ 73.3 mg$O_2\;g^{-1}$, 0.61 ${\sim}$ 1.32 mgP $g^{-l}$ and 0.64 ${\sim}$ 0.88 mgN $g^{-l}$, respectively. Dominant phytoplankton species were chlorophytes (Ankistrodesmus falcatus) and cyanobacteria (Oscillatoria sp. and Merismopedia tennuissima). The total cell density was in the range of 560 ${\sim}$ 35,255 cells $mL^{-l}$.

Analysis on Characteristics of Aquatic Ecosystem Environment in Junam Reservoir (주남저수지의 수생태환경 특성에 대한 분석)

  • Park, Kyung-Hun;Seo, Jeoung-Yoon;You, Ju-Han
    • Korean Journal of Environment and Ecology
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    • v.26 no.5
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    • pp.694-706
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    • 2012
  • The purpose of this study was to offer the raw data for conservation and restoration of aquatic ecosystem by surveying and analysing a water quality, sediment, benthic macroinvertebrate, fish and hydrophyte in Junam reservoir. In the result of analysing the water quality, pH was 8.2~8.4, 6.0~7.5mg/${\ell}$ in COD, 10.0~10.3mg/${\ell}$ in SS, 8.3~11.5mg/${\ell}$ in DO, 0.1mg/${\ell}$ in T-P and 1.2~1.3mg/${\ell}$ in T-N. In case of the sediments, Cd was 0.47~0.52mg/kg, 7.08~7.43mg/kg in Cu, 0.22~0.32mg/kg in As, 0.02~0.03mg/kg in Hg, 6.20~7.45mg/kg in Pb, 32.80~39.70mg/kg in Ni, 513.0~543.0mg/kg in F and 137.0~140.0mg/kg in Zn. $Cr^{6+}$ was not detected. The benthic macroinvertebrates were 432 individuals including 3 phyla, 5 classes, 9 orders, 26 families, 33 genera and 39 species, and the ecological score of benthic macroinvertebrate community(ESB) was 25. The fishes were 8 families and 14 species, and the invasive alien species were 2 taxa including Micropterus salmoids and Lepomis macrochirus. The hydrophytes were 63 taxa including 28 families, 42 genera, 56 species, 1 subspecies and 6 varieties. The emergent plants were 38 taxa(60.3%), 5 taxa(7.9%) in floating-leaved plants and each 10 taxa(15.9%) in free-floating plants and submerged plants.

Evaluation of the Nutrient Removal Performance of the Pilot-scale KNR (Kwon's Nutrient Removal) System with Dual Sludge for Small Sewage Treatment (소규모 하수처리를 위한 파일럿 규모 이중슬러지 KNR® (Kwon's nutrient removal) 시스템의 영얌염류 제거성능 평가)

  • An, Jin-Young;Kwon, Joong-Chun;Kim, Yun-Hak;Jeng, Yoo-Hoon;Kim, Doo-Eon;Ryu, Sun-Ho;Kim, Byung-Woo
    • Clean Technology
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    • v.12 no.2
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    • pp.67-77
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    • 2006
  • A simple dual sludge process, called as $KNR^{(R)}$ (Kwon's Nutrient Removal) system, was developed for small sewage treatment. It is a hybrid system that consists of an UMBR (Upflow multi-layer bioreactor) as anaerobic and anoxic reactor with suspended denitrifier and a post aerobic biofilm reactor, filled with pellet-like media, with attached nitrifier. To evaluate the stability and performance of this system for small sewage treatment, the pilot-scale $KNR^{(R)}$ plant with a treatment capacity of $50m^3/d$ was practically applied to the actual sewage treatment plant, which was under retrofit construction during pilot plant operation, with a capacity of $50m^3/d$ in a small rural community. The HRTs of a UMBR and a post aerobic biofilm reactor were about 4.7 h and 7.2 h, respectively. The temperature in the reactor varied from $18.1^{\circ}C$ to $28.1^{\circ}C$. The pilot plant showed stable performance even though the pilot plant had been the severe fluctuation of influent flow rate and BOD/N ratio. During a whole period of this study, average concentrations of $COD_{cr}$, $COD_{Mn}$, $BOD_5$, TN, and TP in the final effluent obtained from this system were 11.0 mg/L, 8.8 mg/L, 4.2 mg/L, 3.5 mg/L, 9.8 mg/L, and 0.87/0.17 mg/L (with/without poly aluminium chloride(PAC)), which corresponded to a removal efficiency of 95.3%, 87.6%, 96.3%, 96.5%, 68.2%, and 55.4/90.3%, respectively. Excess sludge production rates were $0.026kg-DS/m^3$-sewage and 0.220 kg-DS/kg-BOD lower 1.9 to 3.8 times than those in activated sludge based system such as $A_2O$ and Bardenpho.

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Variations of Properties and Microbial Community during Fermentation of Makgeollies by Isolated Yeasts from Traditional Makgeollies (전통막걸리에서 분리한 효모균주를 이용한 막걸리 발효과정 중의 물성 및 미생물 군집의 변화)

  • Jeon, Myong Je;Jang, Min Kyung;Lee, Sol Jee;Park, Sung Hwan;Kim, Mihyang;Sohn, Jae Hak;Lee, Han-Seung;Lee, Dong-Geun;Lee, Sang-Hyeon
    • Journal of Life Science
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    • v.23 no.6
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    • pp.796-803
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    • 2013
  • Property changes and bacterial characterizations by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) were investigated during the fermentation of Makgeollies by 5 isolated yeast strains. Changes of pH were large between day 0 (pH 6) and day 2 (pH 3) and showed less variation after then. ANOVA analyses revealed that pHs were statistically different with fermentation times (p<0.001), while strains (p=0.60) did not. Acidities were changed from 0.19 to 1.04% and showed rather high increase from day 2, and fermentation times (p<0.001) and strains (p=0.006) represented statistical differences. All strains showed less than 0.150% at amino-type nitrogen contents except S strain showed 0.442% at day 8, and there were no statistical differences with fermentation times (p=0.4558) and strains (p=0.3513). Saccharinities of C strain were higher from day 4, and fermentation times (p<0.0001) and strains (p=0.007) showed statistical differences. Large variation of alcohol concentrations (%) were observed between day 0 (0%) and day 2 (10%) and showed less variation after day 2, and there was no statistical difference with strains. Dominant prokaryotes were Lactobacillus fermentum and Pediococcus pentosaceus, which producing acids and functional materials. Dominant eukaryote was Saccharomyces cerevisiae, which might be resulted from addition of yeasts.

Effect of a Floating Photovoltaic System (FPV) at Chungju Dam (Cheongpung Lake) on Water Quality (충주댐(청풍호) 수상태양광 시설이 호수 수질에 미치는 영향)

  • Kim, Hak Jun;Kwak, Suhknam;Yoon, Min;Kim, Il-Kyu;Kim, Young-Sung;Kim, Dong-sub
    • Korean Journal of Ecology and Environment
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    • v.52 no.4
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    • pp.293-305
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    • 2019
  • In this study we investigated the effect of a floating photovoltaic (FPV) system in Cheongpung Lake on water quality. The FPV with a tilt angle of 33° covered ca. 0.04% of surface area (97 ㎢) of Chungju Lake. The water qualities of the whole lake before and after installation of FPV were first compared. DO, BOD, TOC, and Chl-a of the whole lake were increased, while conductivity decreased after installation period at the significance level of 0.05. This change was probably due to the increased influx of nutrients by 40% resulting from increased precipitation during the same period. We also measured water quality parameters on May and Nov. 2017 at the FPV center (FPVC) and nearby control sites, and compared water quality. The result showed that the FPVC and nearby sites were not significantly different (p>0.05), demonstrating that the FPV does not cause a decline of water quality. The water temperature, light intensity, and phytoplankton community were also measured. The water temperature was not different between the sites, while the light intensity decreased to 27~50%. Despite reduced light intensity at FPVC, the phytoplankton standing crops and the number of species were not significantly different (p>0.05). However, in the early November samples, standing crops was significantly higher in FPVC than control with periphytic diatoms belonging to Aulacoseira genus being dominant. This may be due to the temporal water body behavior or local retention of current by FPV system. This study may provide a measure of future installation of a FPV system.

Community Structure and Distribution of Natural Seaweed Beds on the Eastern Coast of Korea (동해안 천연 해조장의 군집구조와 분포 특성)

  • Park, Gyu Jin;Ju, Hyun;Choi, Ok In;Choi, Chang Geun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.23 no.4
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    • pp.338-346
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    • 2017
  • Natural seaweed beds and habitat environments were investigated using quantitative and qualitative methods from May to December 2015 at 3 sites in Gangneung, Uljin, and Busan along the eastern coast of Korea. In total, 9 green, 23 brown, and 64 red algal taxa were identified. The biomass of the seaweed at Gangneung was 173.2 to $613.8wet\;wt.g/m^2$ of Dictyota divaricata, 360.8 to $520.4wet\;wt.g/m^2$ of Symphyocladia linearis, and 25.9 to $470.8wet\;wt.g/m^2$ of Undaria pinnatifida. At Uljin, these numbers were 5.5 to $256.2wet\;wt.g/m^2$ of Plocamium telfarirae and 46.8 to $241.5wet\;wt.g/m^2$ of Agarum clathratum. The biomass of Sargassum coreanum and Ecklonia cava were 388.1 to $6,972.4wet\;wt.g/m^2$ and 194.9 to $958.5wet\;wt.g/m^2$, respectively, at Busan. S. coreanum and E. cava showed higher biomass compared to other seaweed at Busan. The biomass rate represented an average of 19.2 percent of the total population, ranging from 0.0 to 55.5 percent in Gangneung. In Uljin, the average was calculated as 63.8 percent, and this figure was 48.5 percent in Busan. The percentage of barren ground averaged 46.7 percent in Gangneung and 91.1 percent in Uljin. Uljin showed the highest percentage of barren ground compared to other regions. Sea urchin density appeared to be $6.0ind./m^2$ in Gangneung, $7.0ind./m^2$ in Uljin, and $2.0ind./m^2$ in Busan, with the lowest sea urchin density being that of Busan. In conclusion, the composition of species, appearance ratio, and abundance of vegetation found were similar to previous studies, but it is thought that continuous monitoring is needed due to concerns about physical and chemical pollution caused by global warming, climate change, and coastal development.

PM2.5 Simulations for the Seoul Metropolitan Area: (II) Estimation of Self-Contributions and Emission-to-PM2.5 Conversion Rates for Each Source Category (수도권 초미세먼지 농도모사 : (II) 오염원별, 배출물질별 자체 기여도 및 전환율 산정)

  • Kim, Soontae;Bae, Changhan;Yoo, Chul;Kim, Byeong-Uk;Kim, Hyun Cheol;Moon, Nankyoung
    • Journal of Korean Society for Atmospheric Environment
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    • v.33 no.4
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    • pp.377-392
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    • 2017
  • A set of BFM (Brute Force Method) simulations with the CMAQ (Community Multiscale Air Quality) model were conducted in order to estimate self-contributions and conversion rates of PPM (Primary $PM_{2.5}$), $NO_x$, $SO_2$, $NH_3$, and VOC emissions to $PM_{2.5}$ concentrations over the SMA (Seoul Metropolitan Area). CAPSS (Clean Air Policy Support System) 2013 EI (emissions inventory) from the NIER (National Institute of Environmental Research) was used for the base and sensitivity simulations. SCCs (Source Classification Codes) in the EI were utilized to group the emissions into area, mobile, and point source categories. PPM and $PM_{2.5}$ precursor emissions from each source category were reduced by 50%. In turn, air quality was simulated with CMAQ during January, April, July, and October in 2014 for the BFM runs. In this study, seasonal variations of SMA $PM_{2.5}$ self-sensitivities to PPM, $SO_2$, and $NH_3$ emissions can be observed even when the seasonal emission rates are almost identical. For example, when the mobile PPM emissions from the SMA were 634 TPM (Tons Per Month) and 603 TPM in January and July, self-contributions of the emissions to monthly mean $PM_{2.5}$ were $2.7{\mu}g/m^3$ and $1.3{\mu}g/m^3$ for the months, respectively. Similarly, while $NH_3$ emissions from area sources were 4,169 TPM and 3,951 TPM in January and July, the self-contributions to monthly mean $PM_{2.5}$ for the months were $2.0{\mu}g/m^3$ and $4.4{\mu}g/m^3$, respectively. Meanwhile, emission-to-$PM_{2.5}$ conversion rates of precursors vary among source categories. For instance, the annual mean conversion rates of the SMA mobile, area, and point sources were 19.3, 10.8, and $6.6{\mu}g/m^3/10^6TPY$ for $SO_2$ emissions while those rates for PPM emissions were 268.6, 207.7, and 181.5 (${\mu}g/m^3/10^6TPY$), respectively, over the region. The results demonstrate that SMA $PM_{2.5}$ responses to the same amount of reduction in precursor emissions differ for source categories and in time (e.g. seasons), which is important when the cost-benefit analysis is conducted during air quality improvement planning. On the other hand, annual mean $PM_{2.5}$ sensitivities to the SMA $NO_x$ emissions remains still negative even after a 50% reduction in emission category which implies that more aggressive $NO_x$ reductions are required for the SMA to overcome '$NO_x$ disbenefit' under the base condition.

Dry Matter Yield and Nutrients Uptake of Sorghum${\times}$Sudangrass Hybrid Grown with Different Rates of Livestock Manure Compost (가축분퇴비 시용 수준에 따른 수수${\times}$수단그라스 교잡종의 건물생산 및 양분 흡수)

  • Lim, Sang-Sun;Lee, Sang-Mo;Lee, Seung-Heon;Choi, Woo-Jung
    • Korean Journal of Soil Science and Fertilizer
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    • v.43 no.4
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    • pp.458-465
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    • 2010
  • To investigate the growth and nutrient uptake response of sorghum${\times}$sudangrass ($S{\times}S$) hybrid to different rate of livestock manure compost, a field experiment was conducted in the experimental grassland of Chonnam National University. Six treatments were laid out in a randomized block design with triplicates; control (no input), synthetic fertilizer (20 g N $m^{-2}$ and 20 g $P_2O_5\;m^{-2}$), compost 1 (3.4 g N $m^{-2}$ and 3.6 g $P_2O_5\;m^{-2}$), compost 2 (6.8 g N $m^{-2}$ and 7.2 g $P_2O_5\;m^{-2}$), compost 4 (13.4 g N $m^{-2}$ and 14.4 g $P_2O_5\;m^{-2}$), and compost 6 (20.2 g N $m^{-2}$ and 21.6 g $P_2O_5\;m^{-2}$). Ninety days after treatment, above-ground parts of the plants were harvested and measured for dry matter yield (DMY) and amounts of nutrients (N and P) uptake. Synthetic fertilizer application achieved the greatest DMY (2.4 kg $m^{-2}$) and nutrient uptake (38.3 g N $m^{-2}$ and 15.3 g $P_2O_5\;m^{-2}$). Increasing compost application rate tended to enhance DMY accumulation and nutrient uptake (P<0.01), but DMYs of compost 4 (1.9 kg $m^{-2}$) and 6 (1.8 kg $m^{-2}$) treatments were not different. Therefore, it was suggested that application compost alone may not achieve DMY of $S{\times}S$ hybrid compatible to synthetic fertilizer application. As nutrient uptake efficiency data showed that availability of compost P could be better than SF, it might be a strategy to apply compost as P source with supplementary N application such as liquid manure, SF or green manure if necessary considering availability of N input and the yield goals.

Effects of Cyanobacterial Bloom on Zooplankton Community Dynamics in Several Eutrophic Lakes (부영양호수에서 남조류 bloom이 동물플랑크톤 군집변화에 미치는 영향)

  • Kim, Bom-Chul;Choi, Eun-Mi;Hwang, Soon-Jin;Kim, Ho-Sub
    • Korean Journal of Ecology and Environment
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    • v.33 no.4 s.92
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    • pp.366-373
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    • 2000
  • Toxin production and low digestibility of cyanobacteria are known to cause low exploitability of cyanobacteria by zooplankton. In this study, we compared relative tolerance and compatibility of zooplankton taxa in eight eutrophic lakes, exposed to frequent cyanobacterial blooms, uring the summer season of 1999. Microcystis, Anabaena, Oscillatoria and Phormidium were common cyanobacteria in all lakes. with relatively lower $NO_3-N$ concentration (<0.2 mgN/l) and TN/TP ratio (<20), compared with other lakes where colonial cyanobacteria dominated. Rotifers were dominant zooplankton in most lakes, and among them, Keratella, Polyarthra and Hexathra were common. The laboratory feeding experiment showed that relative copepods that greatly decreased (90%) after 4 day when cyanobacteria were used as the food source of zooplankton, while rotifers gradually increased with the change of dominant taxa from Keratella through Pompholyx to Monostyla. These results suggest that rotifers may be capable of coexisting with cyanobacteria by exploiting them for the food source.

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