• Title/Summary/Keyword: Granite soil

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Selection of Ectomycorrhizal Isolates of Tricholoma matsutake and T. magnivelare for Inoculation on Seedlings of Pinus densiflora In Vitro (소나무 유묘에서 송이 외생균근 형성 균주의 선발)

  • Ka, Kang-Hyeon;Park, Hyun;Hur, Tae-Chul;Bak, Won-Chull
    • The Korean Journal of Mycology
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    • v.36 no.2
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    • pp.148-152
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    • 2008
  • We inoculated hypal suspension of Tricholoma matsutake and T. magnivelare were examined on Pinus densiflora seedlings grown in a granite soil substrate with 1/2 PDMP (12 g/l potato dextrose broth, 1.5 g/l malt extract, and 0.5 g/l peptone) medium. Four months after inoculation, the pine seedlings were examined for infection rate, matsutake aroma, and Hartig-net formation. The roots of pine seedling formed ectomycorrhizal roots in the 9 isolates from 12 isolates of T. matsutake and T. magnivelare. However, the seedlings showed different ectomycorrhizae forming rates among the 9 isolates. While matsutake aroma was confirmed from the ectomycorrhizal seedlings, the pine seedling contaminated by bacteria or fungi did not form matsutake ectomycorrhizae with sickening smell. Thus, the aroma was chosen as a good way for the verification of mycorrhizal infection. At the early stage, the mycorrhizal roots showed unramified and branched types without root hair. They also showed thin mantle layers, Hartig-nets, and turned into black color at later stage. Among the examined strains, that of Yecheon isolated in 1995 showed the best infection rate, which indicated that we need to pay attention to the selection of isolates for better result.

A study on applicability of volumetric water content to predict shallow failure (표층붕괴 예측을 위한 체적함수비 적용성 연구)

  • Suk, Jae-Wook;Song, Hyo-Sung;Kang, Hyo-Sub;Kim, Ho-Jong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.12
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    • pp.737-746
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    • 2019
  • Most landslides in the country are shallow failures triggered by intense rainfall. Many researchers have revealed the possibility of predicting shallow failure through the volumetric water content (VWC). This study examined how to determine shallow failure using the gradient characteristics of the volumetric water content. For this, flume experiments were conducted using weathered granite soil. To confirm the saturation state of the surface layer under a rainfall intensity of 30 and 50mm/hr, VWC sensors were installed at depths of 10 and 20 cm on the upper, middle and lower slope. The test results showed that a shallow failure determination using VWC could be applied limitedly according to the slope degree. In addition, the effective cumulative rainfall due to the rainfall infiltration velocity is considered the main factor for the failure time. The failure prediction using the gradient of the VWC depends on the installation location and depth of the sensor. According to the experimental data, the measured value at 20 cm below the slope was most effective. Therefore, an analysis method of VWC and the method of selecting the installation location confirmed through this study can provide important data for presenting the measurement criteria using VWC in the future.

Geochemical Modeling of Groundwater in Granitic Terrain: the Yeongcheon Area (영천 화강암지역 지하수의 지화학적 모델링)

  • Koh, Yong-Kwon;Kim, Chun-Soo;Bae, Dae-Seok;Yun, Seong-Taek
    • Journal of the Korean Society of Groundwater Environment
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    • v.5 no.4
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    • pp.192-202
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    • 1998
  • We investigated the geochemistry and environmental isotopes of granite-bedrock groundwater in the Yeongcheon diversion tunnel which is located about 300 m below the land surface. The hydrochemistry of groundwaters belongs to the Ca-HCO$_3$type, and is controlled by flow systems and water-rock interaction in the flow conduits (fractures). The deuterium and oxygen-18 data are clustered along the meteoric water line, indicating that the groundwater are commonly of meteoric water origin and are not affected by secondary isotope effects such as evaporation and isotope exchange. Tritium data show that the groundwaters were mostly recharged before pre-thermonuclear period and have been mixed with younger surface water flowing down rapidly into the tunnel along fractured zones. Based on the mass balance and reaction simulation approaches, using both the hydrochemistry of groundwater and the secondary mineralogy of fracture-filling materials, we have modeled the low-temperature hydrogeochemical evolution of groundwater in the area. The results of geochemical simulation show that the concentrations of Ca$\^$2+/, Na$\^$+/ and HCO$_3$and pH of waters increase progressively owing to the dissolution of reactive minerals in flow paths. The concentrations of Mg$\^$2+/ and K$\^$+/ frist increase with the dissolution, but later decrease when montmorillonite and illitic material are precipitated respectively. The continuous adding of reactive minerals, namely the progressively larger degrees of water/rock interaction, causes the formation of secondary minerals with the following sequence: first hematite, then gibbsite, then kaolinite, then montmorillonite, then illtic material, and finally microcline. During the simulation all the gibbsite is consumed, kaolinite precipitates and then the continuous reaction converts the kaolinite to montmorillonite and illitic material. The reaction simulation results agree well with the observed, water chemistry and secondary mineralogy, indicating the successful applicability of this simulation technique to delineate the complex hydrogeochemistry of bedrock groundwaters.

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Present Deterioration Situation and Study on the Cleaning of the Surface of the Octagonal nine storied pagoda of Woljeongsa Temple (월정사팔각구층석탑의 손상현황과 표면오염물 제거연구)

  • Hwang, Jeong Eun;Kim, Sa Dug;Jung, Hee Soo
    • 보존과학연구
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    • s.33
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    • pp.125-148
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    • 2012
  • The Octagonal nine storied pagoda of Woljeongsa Temple consists mainly of granite with the rockforming minerals quartz, plagioclase, microcline, and biotite. The surface of the stone stupa is light brown that has been discolored by the rust from the metal ornament and aids. The surface of the stylobate and roof stone is colonized by biological contaminants. Therefore, a comprehensive deterioration diagnosis was carried out in this study, and conservation treatment was conducted. It was proven that the $Fe^{2+}$ yield increases depending on the count of poultice used with oxalic acid, but the $Mg^{2+}$, $Al^{3+}$, and $Ca^{2+}$ yields were marginal following the preliminary test. Therefore, the use of poultice is an effective way of removing the rust, and only marginally influences the rock. The biological contaminants were removed through dry cleaning, and the soil located under the contaminants was removed through wet cleaning. Based on this, the dry and wet cleaning of all the biological contaminants, and the use of poultice with oxalic acid, were done to remove the rust. For the conservation treatment of the metal ornament, the rust was removed through physical cleaning, and anticorrosion treatment was performed on the iron ornament using Renaissance wax and copper ornament by BTA.

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Rare Earth Element Contents of the Ginsengs and their Soils, Keumsan area (금산 인삼과 토양의 희토류 원소 함량관계)

  • Song, Suck-Hwan;Min, Ell-Sik;Yoo, Sun-Kyun;Lee, Yong-Gyoo
    • Journal of Ginseng Research
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    • v.30 no.1
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    • pp.31-40
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    • 2006
  • Ginsengs(1-3 years old) from the Keumsan were analysed for the rare earth element(REE) contents and compared with their soils from the biotite granite(CR), phyllite(PH) and shale(SL) areas. In the soils, high REE contents and correlations were found in the SL. In the ginsengs, high element contents were shown in the SL. High correlations were found in the 3 year. In the upper parts, the 2 year of the GR was mainly high. Comparing with the same aged ginsengs, high elements were shown in the SL. Positive correlations were dominated and high correlations were shown in the 3 year ginsengs. In the root parts, the GR was high in the 2 year while the PH and SL were high in the 3 year. Comparing with the same ages, high elements were shown in the SL. High correlation relationships were found. Comparing between upper and root parts, the upper parts were mainly high, LREE showed big differences and relative ratios of the 2 year were mainly high. Comparing between soils and ginsengs, the soils were mainly high. Ratios between soils and root parts(soils/root parts) were higher than those of the upper parts. Ratios of the LREE showed big differences relative to those in the HREE and the ratios increased with ages. Overall results suggested that ginsengs of the SL were similar to those of soils and those of the PH showed big differences.

Adsorption Characteristics of Heavy Metal and VOCs of Pyrolysis Char from Organic Waste Sludge (유기성 폐슬러지의 열분해 차르에 대한 중금속 및 VOCs 흡착특성)

  • Park, Sang-Sook;Kang, Hwa-Young
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.2
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    • pp.130-137
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    • 2005
  • This research programme include investigation of the adsorption behavior of heavy metals and VOCs by Pyrolysis char for using landfill cover material. The volatile potions in the sludge gasified during the pyrolysis period and gave birth to porosity throughout the matrix. The result of the ad/desorption experiment of nitrogen to find out the formation of some pore by the gasification of the volatile matter, we can certify that the pyrolysis char($14.56\;m^2/g$) has increased twice more than the organic wasted sludge($6.68\;m^2/g$) in specific surface area. The pyrolysis char has the adsorption characteristic of medium type of Type II and V in BDDT classification, and showed a little micro pore. In the adsorption experiment of ethylbenzene and toluene, as a result of applying the Freundlich adsorption isotherms, the pyrolysis char was higher in the adsorptivity of ethylbenzene and toluene than the granite and the organic wasted sludge. The results of the heavy metal adsorption test for the char indicated that it had some ability of adsorption. It is suggest that pyrolysis char has some advantages for utilizing as landfill covers because the pyrolysis char can adsorb/absorb hazardous substances from the landfill sites and inhibit the ground water and soil contamination.

Properties of Cementless Loess Mortar Using Eco-Friendly Hardening Agent (친환경 무기질 고화재를 사용한 무시멘트 황토모르타르의 특성)

  • Jung, Yong-Wook;Kim, Sung-Hyun;Lee, Dong-Gyu
    • Journal of the Korean Recycled Construction Resources Institute
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    • v.3 no.4
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    • pp.355-365
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    • 2015
  • This study examined the fluidity and strength properties, water resistance, durability, and freeze-thaw of cementless loess mortar using an eco-friendly hardening agent. The experimental result indicates that 28 days compressive and flexural strength of the loess mortar was increased regardless of the weathered granite soil and loess mixture ratio as the replacement ratio of the hardening agent increases. The strengths were significantly increased until 14 days regardless of the hardening agent, while the effect on the strengths increasement was relatively low after 14 days. Thus, the strength development of loess mortar concrete was found to be faster than that of the normal concrete. In addition, when the hardening agent of 10% was used, the average flexural strength was 1.7MPa which is insufficient compared to the 28-day flexural strength of 4.5MPa for the paving concrete. However, the flexural strengths of the loess mortar concrete using the hardening agents of 20% and 30% were 4.0MPa and 5.3MPa, respectively. Thus, the hardening agent need to be at least 20% so that the loess mortar can be used for paving concrete. The experiment for water resistance shows that the repeated absorption and dry reduced mass regardless of the mixing ratio of the loess. The maximum length change also decreased with increasing the substitution rate loess mixture ratio and the hardening agent. The result of the freeze-thaw resistance test indicates that the relative dynamic modulus of elasticity at 300 cycle freeze-thaw with the hardening agents of 20% and 30% were 75% and 79%, relatively. Thus, the hardening agent of at least 20% is required to obtain the relative dynamic modulus of elasticity of 60% for the loess mortar.

Stress Analysis of Fill Dam by FEM (FEM에 의한 필댐의 응력해석(應力解析))

  • Kang, Yea Mook;Cho, Seong Seup;Yang, Hae Jin
    • Korean Journal of Agricultural Science
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    • v.19 no.1
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    • pp.79-90
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    • 1992
  • The embankment material of Andong Dam was the decomposed granite soil, and FEM analysis with settlement and stress characteristics were studied in this thesis. and also the results were as follows: 1. The vertical settlement of dam quite nearly coincides with the calculated one by FEM. A maximum value of the measured and the calculated is 40cm and 42cm, respectively, at the EL. 130m. 2. The measured settlement values of the central parts in elevation are nearly the same as those of the calculated, and the settlement values in order of magnitude are in core, filter, random and rock. 3. Horizontal deformation of max. 21cm in downstream is larger than that of max. 17cm in upstream, which is highly influenced by the water pressure of reservoir water level and the earth pressure of coffer dam in upstream. 4. Reverse arching effect of vertical stress in streamflow section are caused by the difference of stiffness, because stiffness is larger in core zone than in filter zone. 5. Load transfer ratio which is the ratio of principal stress of core zone and filter zone is 1.06, which clearly showes the reverse arching effect in vertical stress.

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Quantitative Deterioration Assessment and Microclimatic Analysis of the Gyeongju Seokbinggo (Ice-storing Stone Warehouse), Korea (경주석빙고의 정량적 훼손도 평가와 미기후환경 분석)

  • Kim, Ji-Young;Lee, Chan-Hee;Lee, Myeong-Seong
    • Journal of Conservation Science
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    • v.25 no.1
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    • pp.25-38
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    • 2009
  • The Gyeongju Seokbinggo (Treasure No. 66) is an ice-storing stone warehouse, consisting mainly of alkaligranite which shows milky white color and medium-grained textures with drusy cavities. As results of deterioration assessment, the deterioration rates were determined as crack (12.5%), disjoining (6.7%), breaking-out (25.1%), exfoliation (20.9%), efflorescence (6.5%), brown discoloration (9.8%), darkgray discoloration (2.0%) and biological discoloration (36.5%). Comprehensive physical deterioration rate and discoloration rate were calculated as 43.7% and 68.7%, respectively, that indicates the Seokbinggo has been severely weathered. Indoor relative humidity was above 90% except in winter season. Indoor microclimate was hardly fluctuating although indoor microclimate was dependent on the outdoor climate. The main cause of deterioration was high relative humidity and a long time of wetness due to penetration of rain, underground water and condensation. It was identified that the water brought out biological discoloration, dissolution of minerals, structural movement and efflorescence, and the dust from the ground soil in front of the entrance accelerated brown and dark gray discoloration on the stone surface.

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Geochemistry and Stable Isotopes of Carbonated Waters in South Korea (남한 탄산수의 지구화학적 특성과 안정동위원소 조성)

  • 윤정아;김규한
    • Journal of the Korean Society of Groundwater Environment
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    • v.7 no.3
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    • pp.116-124
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    • 2000
  • Geochemical and isotopic analyses were carried out to investigate hydrochemical characteristics, source of carbon species in the carbonated waters in South Korea. Most Korean carbonated waters from different geologic settings are characterized by a Ca-HCO$_3$type with a relatively low pH range from 5.3 to 6.3 (avg. 6.0). The concentrations of cations and anions in the carbonate waters are in the order of Ca$^{2+}$>Na$^{+}$>Mg$^{2+}$>Si$^{4+}$>Fe$^{2+}$>K$^{+}$ and HCO$_3$$^{-}$>SO$_4$$^{2-}$>Cl$^{-}$, respectively. The HCO$_3$$^{-}$ ion is more enriched in the carbonated water from the sedimentary rock and granitic rock of Mesozoic age in the Gyungsang basin(GII) and the Precambrian metamorphic rock and Jurassic granitic rocks of the Gyunggj massif in the Gangwon province(GⅠ) than those of the meta-sedimentary rock and granite in the Ogcheon zone(GⅢ). Based on the oxygen and hydrogen isotopic data, the carbonated waters are derived from the meteoric water, showing apparent latitude and altitude effects. The $delta$$^{13}$C values of carbon species in the carbonated water are in between -6.23 and 0.0 $textperthousand$, suggesting inorganic source of carbon originated from the carbonate mineral and carbonate rock in the aquifer.

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