• Title/Summary/Keyword: Water area

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The Effects of Carbonate Minerals in Gully-pot Sediment on the Leaching Behavior of Heavy Metals Under Acidified Environment (우수관퇴적물에 함유된 탄산염광물이 산성환경에서의 중금속 용출거동에 미치는 영향 평가)

  • 이평구;유연희
    • Economic and Environmental Geology
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    • v.35 no.3
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    • pp.257-271
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    • 2002
  • One of the main interests in relation to heavily contaminated gully-pot sediment in urban area is the short term mobility of heavy metals, which depends on the pH of acidic rainwater and on the buffering effects of carbonate minerals. The buffering effects of carbonates are determined by titration (acid addition). Leaching experiments are carried out in solutions with variable initial HN03 contents for 24h. The gully-pot sediment appears to be predominantly buffered by calcite and dolomite. In case of sediment samples, which highly contain carbonates, pH decreases more slowly with increasing acidity. On the other hand, for the sediment samples, which less contain carbonate minerals, pH rapidly drops until it reaches about 2 then it decreases slowly. The leaching reactions are delayed until more acid is added to compensate for the buffering effects of carbonates. The Zn, Cu, Pb and Mn concentrations of leachate rapidly increase with decreased pH, while Cd, Co, Ni, Cr and Fe dissolutions are very slow and limited. The solubility of heavy metals depends not only on thc pH values of leachatc but also on the speciation in which metals are associated with sediment particles. In slightly to moderately acid conditions, Zn, Cd, Co, Ni and Cu dissolutions become increasingly important. As deduced from leaching runs, the relative mobility of heavy metals at pH of 5 is found to be: Zn > Cd > Co > Ni > Cu » Pb > Cr, suggesting that moderately acid rainwater leach Zn, Cd, Co, Ni and Cu from thc contaminated gully-pot sediment, while Pb and Cr would remain fixed. The buffering effects of Ca- and Mg-carbonates play an important role in delaying as well as limiting the leaching reactions of heavy metals from highly contaminated gully-pot sediment. The extent of such a secondary environmental pollution will thus depends on how well the metals in sediment can be leached by somewhat acidic rain water. Changes in the physicochemical environments may result in the severe environmental pollution of heavy metals. These results are to be taken into account in the management of contaminated sediments during rainstorms.

Feeding Characteristics of the Japanese Anchovy, Engraulis japonicus According to the Distribution of Zooplankton in the Coastal Waters of Southern Korea (한국 남해 연안 해역에서 출현하는 동물플랑크톤의 분포에 따른 멸치 섭이 특성)

  • Kim, Min Jung;Youn, Seok Hyun;Kim, Jin-Yeong;Oh, Chul-Woong
    • Korean Journal of Environmental Biology
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    • v.31 no.4
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    • pp.275-287
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    • 2013
  • The Japanese anchovy Engraulis japonicus is a widespread species in the western North Pacific and major fishery resource. To understand the spatio-temporal variation of anchovy prey items in the coastal waters of southern Korea, the stomach contents of anchovy and the structure of the zooplankton community were analysed at three sites (Jindo, Yeosu and Tong-yeong) from July 2011 to February 2012. The main prey items in Yeosu and Jindo were cyprid stage of barnacle (>35%) and copepod Calanus sinicus (>22%) in July, respectively, while, predominant ones in Tongyeong were small copepods, Paracalanus parvus s.l. (41%) and Corycaeus affinis (22%). During this period, the dominant zooplankton were cladoceran Evadne tergestina (39%) in Yeosu, small copepod, P. parvus s.l. (28%) in Jindo and cladoceran E. tergestina (14%) in Tongyeong. The dominant prey items were barnacle larvae and copepods in summer, phytoplankton and Pseudodiaptomus marinus in autumn and P. parvus s.l. and cold water copepod, Centropages abdominalis in winter. Anchovy prefer the prey item C. sinicus (3%) over E. tergestina (39%), which was a dominant species in the catching site in summer. P. marinus (0.5%) and C. abdominalis (0.9%) were preferred over P. parvus s.l. (30%, 21%) in autumn and winter, respectively. Prey items varied with area and season in the coastal waters of southern Korea. These results suggest that the prey selectivity of anchovy showed high flexibility and adaptability in the study waters.

Evaluation of MODIS-derived Evapotranspiration at the Flux Tower Sites in East Asia (동아시아 지역의 플럭스 타워 관측지에 대한 MODIS 위성영상 기반의 증발산 평가)

  • Jeong, Seung-Taek;Jang, Keun-Chang;Kang, Sin-Kyu;Kim, Joon;Kondo, Hiroaki;Gamo, Minoru;Asanuma, Jun;Saigusa, Nobuko;Wang, Shaoqiang;Han, Shijie
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.11 no.4
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    • pp.174-184
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    • 2009
  • Evapotranspiration (ET) is one of the major hydrologic processes in terrestrial ecosystems. A reliable estimation of spatially representavtive ET is necessary for deriving regional water budget, primary productivity of vegetation, and feedbacks of land surface to regional climate. Moderate resolution imaging spectroradiometer (MODIS) provides an opportunity to monitor ET for wide area at daily time scale. In this study, we applied a MODIS-based ET algorithm and tested its reliability for nine flux tower sites in East Asia. This is a stand-alone MODIS algorithm based on the Penman-Monteith equation and uses input data derived from MODIS. Instantaneous ET was estimated and scaled up to daily ET. For six flux sites, the MODIS-derived instantaneous ET showed a good agreement with the measured data ($r^2=0.38$ to 0.73, ME = -44 to $+31W\;m^{-2}$, RMSE =48 to $111W\;m^{-2}$). However, for the other three sites, a poor agreement was observed. The predictability of MODIS ET was improved when the up-scaled daily ET was used ($r^2\;=\;0.48$ to 0.89, ME = -0.7 to $-0.6\;mm\;day^{-1}$, $RMSE=\;0.5{\sim}1.1\;mm\;day^{-1}$). Errors in the canopy conductance were identified as a primary factor of uncertainty in MODIS-derived ET and hence, a more reliable estimation of canopy conductance is necessary to increase the accuracy of MODIS ET.

A Study on Value of Geumseonjeong as a Scenic Spot (금선정의 명승적 가치에 관한 연구)

  • Choi, Ji-Young;Lee, Jin-Hyang;Lee, Jae-Keun
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.30 no.1
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    • pp.113-124
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    • 2012
  • The Confucian culture of the Chosun Dynasty has a great effect on the construction of ByeolSeo gardens. Among them, especially the gardens built in Gyeongsang Province areas, where a great number of Confucian scholars were produced in the beautiful natural environment, have maintained various heritage of Confucian culture established by the scholars. Along with the Nakdong River, we can find so many cultural assets of buildings such as head houses, ByeolSeo gardens, including the literary remains such as administrative certificates, poetry and prose, and records of pavilions, which show the trace of the scholars who followed the instructions of the doctrines of Chu-tzu. The Geumseonjeog located in Punggi County, Gyeongsangbuk Province, which was the ByeolSeo gardens possessed by Geumgye Whang Jun-ryang(1517-1563), who was the governor of the area and one of the representative students of Toigye Lee Whang. The building is located nearby the Geumseon Valley with beautiful natural scenery under Sobaek Mountain. Especially the pine forest around the valley boasts a unique natural setting. This study is aimed to analyze the value of natural scenic spot of the Geumseonjeong through the surveys on surroundings, topography, vegetation and water system. including the value of humanistic elements focused on the writings such as 'Geumgyejip' written by Whang Jun-ryang and Lee Whang, another 'Geumgyejip' written by Ryu un-ryong, and 'Geumgyejeongsajungsugi' written by Hong Gyeong-ryeom. And also, the scenic spot value of the signboards such as the 'Geumgyejeongsajungsugi' written by Ryu un-ryong, 'Geumgyejeong' by Lee Han-il, 'Geumgyejeong' written by Jo Un-hyeong and 'Geumgyejeongsa, written by Lee Jung-gi, was analyzed. And the historical and cultural value was analyzed through the semantic interpretation of the series of poetry and pose and the old map established in 1872. In respect of the scenery, the surroundings of the Geumseon Valley boast the outstanding settings as the clean mountain stream in front of the Geumseonjeong makes a beautiful harmony with the pine forest. The pine forest surrounding the Geumseon Valley has played a secret role in the history of the village. Considering the fact that the pine forest was expressed in the map of Punggi County produced in 1872, it may be assumed that the forest was regarded to have historical and scenic value in those times. Considering the fact that the words like 'Beautiful' and 'Scenic spot' were used in the writings like 'Geumgyejip' and there were meeting places around the valley, we can recognize the value of the place as a scenic spot. The beautiful natural scenery surrounding the ByeolSeo gardens, and the increase in humanistic value of the poetry and prose, including the administrative certificates, has recently brought about the cases in which some scenic spots of the ByeolSeo gardens were designated as cultural assets. According to the value as a scenic spot and semantic interpretation of the Geumseonjeong, the pavilion appeared to have a great scenic spot value as a ByeolSeo gardens, so that this study was designed to prepare criteria with which the pavilion may be designated as a scenic spot of ByeolSeo gardens.

The Business Model & Feasibility Analysis of the Han-Ok Residential Housing Block (한옥주거단지 사업모델구상 및 타당성 분석)

  • Choi, Sang-Hee;Song, Ki-Wook;Park, Sin-Won
    • Land and Housing Review
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    • v.2 no.4
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    • pp.453-461
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    • 2011
  • This study is to derive a project model based on potential demand for Korean-style houses, focusing on new town detached housing sites that LH supplies and to test validity of the derived model and to present the direction and supply methods of the projects. The existing high-class new town Korean-style housing developments that have been considered were found to have little business value due to problems in choice of location and discordance of demand, so 6 types of projects were established through the methods of changes in planned scale, combined use, and subdivision of plot of land based on the results of survey. The type that has the highest business value among the project models was block-type multifamily houses, and this can be interpreted as the increase in total construction area leading to increase inrevenues of allotment sales due to economies of scale. The feasibility of mass housing model in which small-scale Korean-style houses are combined with amenities was found to be high, and if the same project conditions as those of the block-type multifamily houses are applied, the business value of the Korean-style tenement houses was found to be high. Besides, the high-class housing models within block-type detached housing areas are typical projects that the private sector generally promotes, and the construction cost was found to be most expensive with 910 million won per house. In order to enhance the business value of the Korean-style housing development, collectivization such as choice of location, diversification of demand classes, optimization of house sizes, and combination of uses is needed. And in order to adopt Korean-style houses in the detached housing sites, the adjustments and division of the existing planned plots are needed, and the strategies to cope with new demand through supplying Korean-style housing types of sites can be suggested. Also breaking away from the existing uniform residential development methods, the development method through supplying original land that is natural land not yet developed besides basic infrastructures (main roads and water and sewage) can be considered, and as the construction of more than 1~2 stories building is impossible due to the structure of Korean-style house roof and furniture. So it can be suggested that original land in the form of hilly land is considered to be most suitable to large-scale development projects.

Study on Morphological Characteristics of Rice Soils in Mangeong-Dongjin and Yeongsan Watersheds (영산강(榮山江)과 만경(萬頃)·동율강유역(東律江流域)의 답토양분포(畓土壤分布)에 관(關)하여)

  • Kim, Han-Myoung;Cho, Guk-Hyun;Yoo, Chul-Hyun;Eun, Mu-Young;Rho, Sung-Pyo;Shin, Yong-Hwa
    • Korean Journal of Soil Science and Fertilizer
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    • v.17 no.2
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    • pp.125-133
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    • 1984
  • To obtain the basic date for the improvement of cultural and managemental problems caused by soil characteristics and soil productivity in rice cultivation of Honam area, morphological characteristics of rice soils were investigated in Mangeng-Dongjin and Yeongsan Water-sheds, and compaired differences between two major Watersheds. The results obtained are summarized as follows: 1. According to U.S.D.A. Soil Taxonomy Classification System, eight great groups are distributed in rice soils of two major Watersheds. More than 50% of rice paddy soils are classified as Haplaquepts. 2. Two Watersheds are quite different in soil parent materials. In Mangeong-Dongjin Watershed, most soils (55.1%) are derived from fluvic-marine deposits. Remainders are derived from local alluvium (24.7%) and alluvium (14.2%). But in Yeongsan Watershed, the order is local alluvium>alluvium>fluvio-marine deposits. 3. Rice soils occur mostly in coastal and inland flat-site with the slope of less than 2% (57.8%) in Mangeong-Dongjin Watersheds. However, in Yeongsan Watershed, flat-site and low undulating terrace are mostly distributed (52.9%). 4. About 81.9, 61.4 and 53.3% of rice soils are classified as fine textured in Yeongsan, Dongjin, and Mangeong Watersheds, respectively. 5. More normal paddy soils and less sandy paddy soils are distributed in Yeongsan Watershed. The results indicate that more rice soils are classified as productivity classes of I and II in Yeongsan Watershed than in Mangeong-Dongjin Watersheds.

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Feeding Behavior of Crustaceans (Cladocera, Copepoda and Ostracoda): Food Selection Measured by Stable Isotope Analysis Using R Package SIAR in Mesocosm Experiment (메소코즘을 이용한 지각류, 요각류 및 패충류의 섭식 성향 분석; 탄소, 질소 안정동위원소비의 믹싱모델 (R package SIAR)을 이용한 정량 분석)

  • Chang, Kwang-Hyeon;Seo, Dong-Il;Go, Soon-Mi;Sakamoto, Masaki;Nam, Gui-Sook;Choi, Jong-Yun;Kim, Min-Seob;Jeong, Kwang-Seok;La, Geung-Hwan;Kim, Hyun-Woo
    • Korean Journal of Ecology and Environment
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    • v.49 no.4
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    • pp.279-288
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    • 2016
  • Stable Isotope Analysis(SIA) of carbon and nitrogen is useful tool for the understanding functional roles of target organisms in biological interactions in the food web. Recently, mixing model based on SIA is frequently used to determine which of the potential food sources predominantly assimilated by consumers, however, application of model is often limited and difficult for non-expert users of software. In the present study, we suggest easy manual of R software and package SIAR with example data regarding selective feeding of crustaceans dominated freshwater zooplankton community. We collected SIA data from the experimental mesocosms set up at the littoral area of eutrophic Chodae Reservoir, and analyzed the dominant crustacean species main food sources among small sized particulate organic matters (POM, <$50{\mu}m$), large sized POM (>$50{\mu}m$), and attached POM using mixing model. From the results obtained by SIAR model, Daphnia galeata and Ostracoda mainly consumed small sized POM while Simocephalus vetulus consumed both small and large sized POM simultaneously. Copepods collected from the reservoir showed no preferences on various food items, but in the mesocosm tanks, main food sources for the copepods was attached POM rather than planktonic preys including rotifers. The results have suggested that their roles as grazers in food web of eutrophicated reservoirs are different, and S. vetulus is more efficient grazer on wide range of food items such as large colony of phytoplankton and cyanobacteria during water bloom period.

Effects of Dietary Nutrient Levels on Growth Performance, Blood Urea Nitrogen, and Meat Quality in Finishing Pigs (비육돈에 있어서 영양소 및 원료 첨가수준이 다른 사료의 급여가 생산성, 혈중 요소태질소 및 육질특성에 미치는 영향)

  • Shin, Seung-Oh;Cho, Jin-Ho;Kim, Hae-Jin;Chen, Ying-Jie;Yoo, Jong-Sang;Wang, Yuan;Huang, Yan;Kim, In-Ho
    • Food Science of Animal Resources
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    • v.27 no.4
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    • pp.387-391
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    • 2007
  • This study was conducted to evaluate effects of dietary nutrient levels on growth performance, blood urea nitrogen, and meat quality in finishing pigs. A total of ninety six pigs ($Landrace{\times}Yorkshire{\times}Duroc$) were used in this 66 day study. Dietary treatments included 1) T1 (ME 3,441 kcal/kg, CP 16.30%, Lysine 0.93%), 2) T2 (ME 3,433 kcal/kg, CP 17.00%, Lysine 1.00% and 3) T3 (ME 3,449 kcal/kg, CP 17.00%, Lysine 1.00%). During the overall period, there were no significant differences in ADG (average daily gain), ADFI (average daily feed intake), gain/feed ratio or BUN (blood urea nitrogen) among the treatments (p>0.05). The $b^*$ value of M. longissimus dorsi muscle color significantly increased (p<0.05) with T3 treatment compared to T2 treatment. However, there were no differences in the $L^*\;and\;a^*$ values, pH, M. logissimus dorsi area, drip loss, cooking loss, TBARS and WHC (water holding capacity) for pigs fed the various treatments (p>0.05). The total feed cost per kg of weight gain was not significantly different among the various dietary treatments (p>0.05). In conclusion, these results show no effects of dietary nutrient levels on growth performance and meat quality in finishing pigs, and also suggest that a high nutrient density diet may not be a beneficial feeding strategy for finishing pigs in terms of cost.

Investigations on the Adsorption Characteristics of $SO_2$ Gas on Fixed Bed Manganese Nodule Column (고정(固定) 흡착층(吸着層)에서 망간단괴(團塊)의 $SO_2$ 가스 흡착(吸着) 특성(特性)에 관한 연구(硏究))

  • Baek, Mi-Hwa;Kim, Dong-Su;Jung, Sun-Hee;Park, Kyoung-Ho
    • Resources Recycling
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    • v.15 no.4 s.72
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    • pp.3-12
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    • 2006
  • The feasibility for the employment of manganese nodule as an adsorbent for $SO_{2}$ gas has been investigated. The specific surface area of manganese nodule particle, which used in the experiments, was ca. $221.5m^{2}/g$ and the content of sulfur in manganese nodule was observed to significantly increase after $SO_{2}$ was adsorbed on it. The EPMA for the distilled water-washed and methanol-washed manganese nodule particle after $SO_{2}$ adsorption showed that its sulfur content was slightly decreased to 14.7% and 13.1% respectively, from 15.4% before washing. The XRD analysis of manganese nodule showed that todorokite and birnessite, which are manganese oxides, and quartz and anorthite were the major mineralogical components and weak $MnSO_{4}$ peaks were detected after $SO_{2}$ was adsorbed on manganese nodule. For an comparative investigation, limestone was also tested as an adsorbent for $SO_{2}$, however, no peaks for $CaSO_{4}$ were found by XRD analysis after the adsorption of $SO_{2}$. As the size of adsorbent increased, time for breakthrough was decreased and the adsorbed amount of $SO_{2}$ was also diminished. The $SO_{2}$ adsorption was hindered when its flow rate became high and the adsorption capacity of manganese nodule was observed to be superior to that of limestone. In addition, the mixture of manganese nodule and limestone did not show an increase in the adsorption of $SO_{2}$. Finally, as the temperature was raised, the adsorbed amount of adsorbate on manganese nodule was found to be decreased.

Methods that can be Substituted for Earth Healing of Seedling by Using the Plastic Vinyl and their Micro-climatical Characteristics (프라스틱비닐제품(製品)을 이용(利用)한 가식대치방법(假植代置方法)과 미기상학적(微氣象學的) 특성(特性))

  • Ma, Sang Kyu;Lee, Jang Soo
    • Journal of Korean Society of Forest Science
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    • v.47 no.1
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    • pp.44-51
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    • 1980
  • In order to find out the suitable methods that can omit the earth healing and increase the survival through improving the seedling-healing and transportable methods. Several trials with plastic vinyl have been done and its results are as follows: 1. Though P. rigitaeda seedling have been stored in the black and white vinyl sack for 35 days in the storehouse. This seedling have survived with very high percentage as Table 1. This means that the earth healing work at the nursery or planting area can be omitted if seedling sould be stored in the storehouse by using the vinyl sack. The possibilities of long-period storage in the black and white vinyl sack seem to be come from the reasons that air humidity in the sack is nearly 100% and its air temperature is only around $15^{\circ}C$ with very little difference between day and night time. This sack also can be utilized in place of the planting sack, and though this sack with seedling have been laid under direct sunshine for 1 to 2 days. Any difference between the sack stored in the storehouse has not been observed on the survival specially Table 2. 2. When the bundled seedling have been covered with the black and white vinyl instead of earth healing, even if these seedling have been laid for 18 days under the vinyl. This seedling show us high survival as Table 3. High humidity with nearly 95%, very little difference of air temperature between day and night time under the vinyl and not so big difference between out-and inside temperature could be reasons of high survival to be considered. So through covering by the black and white vinyl. The labour power for earth healing works can be saved also. 3. In order to protect the healed seedling from the direct sunshine and the eva-transpiration. Black vinyl net and reed mat could be effective for this purpose. Because vinyl net could intercept around one to third, reed mat two to third of total solar energy and also suppress more than 50% of total water loss by the transpiration.

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