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The Potential Acid Sulfate Soils Criteria by the Relation between Total-Sulfur and Net Acid Generation (전황함량과 순산발생능력의 상관관계를 통한 잠재특이산성토양 기준 설정)

  • Moon, Yonghee;Zhang, Yong-Seon;Hyun, Byung-Keun;Sonn, Yeon-Kyu;Park, Chan-Won;Song, Kwan-Cheol
    • Korean Journal of Soil Science and Fertilizer
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    • v.45 no.6
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    • pp.904-909
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    • 2012
  • Acid sulfate soil (ASS) and potential acid sulfate soil (PASS) are distribution in worldwide and originate from sedimentary process, volcanic activity, or metamorphism and are problematic in agriculture and environmental due to their present and potential acidity developed by the oxidation. The PASS was defined as soil materials that had sulfidic layer more than 20 cm thick within 4 m of the soil profile and contained more than 0.15% of total-sulfur (T-S). A tentative interpretative soil classification system was proposed weak potential acid sulfate (T-S, 0.15-0.5%), moderate potential acid sulfate (T-S, 0.5-0.75%) and strong potential acid sulfate (T-S, more than 0.75%). PASS due to excess of pyrite over soil neutralizing capacity are formed. It provides no information on the kinetic rates of acid generation or neutralization; therefore, the test procedures used in acid base account (ABA) are referred to as static procedures. The net acid generation (NAG) test is a direct method to measure the ability of the sample to produce acid through sulfide oxidation and also provides and indication. The NAG test can evaluated easily whether the soils is PASS. The samples are mixed sandy loam and the PAS from the hydrothermal altered andesite (1:3, 1:8, 1:16, 1:20, 1:40, 1:80 and 1:200 ratios) in this study. We could find out that the NAG pH of the soil containing 0.75% of T-S was 2.5, and that of the soil has 0.15% of T-S was 3.8. NAG pH test can be proposed as soil classification criteria for the potential acid sulfate soils. The strong type has NAG pH of 2.5, the moderate one has NAG pH of 3.0, and the weak one has NAG pH of 3.5.

Geochemical and Isotopic Study of the Kumho River (금호강 하천수의 지구화학 및 동위원소 연구)

  • Kim, Yeong-Kyoo;Nam, Eun-Kyung
    • Economic and Environmental Geology
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    • v.42 no.6
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    • pp.527-539
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    • 2009
  • The Kumho River flows through volcanic and sedimentary rocks at upstream and downstream regions and also through industrial district including dyeing complex before it meets the Nakdong River, and as a result, many factors can influence the geochemistry of river water. The concentrations of dissolved ions generally increased as it flows downstream. The concentrations of cations are in the order of Ca>Na>Mg>K, and those of anions are $HCO_3$>$SO_4$>Cl>$NO_3$. These results show that the weathering of sandstone and shale containing carbonate including calcite caused the enrichment of Ca and $HCO_3$. At first 4 sampling sites, Si contents are relatively high mainly due to the weathering of silicate minerals of volcanic rocks. However, Na and $SO_4$ contents are higher at downstream sites due to the industrial and municipal sewage. Piper diagram also shows that the geochemical patterns changed from Ca-$HCO_3$ to Ca-Cl/Ca-$SO_4$ and Na-Cl/Na-$SO_4$ type. When comparing the samples collected in May and July, the concentrations of dissolved ions in July are generally lower than those in May, which indicates that dilution by precipitation played an important role. In July the relative concentration of Ca increased, indicating that Ca in soils probably from fertilizer were mixed into the river water by precipitation. The river waters are mainly from precipitation. The dissolved ions are mainly from weathering of carbonate minerals and pollutants from municipal sewage and discharged water from industrial complex. The composition of oxygen and deutrium isotope in July showed higher values, which is contrary to the amount effect, maybe due to Youngchon Dam. The nitrogen isotope showed lower values in July than those in May, which can be interpreted to indicate mixing of nitrate from soils and fertilizer in the cultivated land by the heavy rain. The isotope composition of nitrate increased downstream, indicating that the influence of sewage and animal manure also increased downstream.

Effect of Fly Ash Fertilizer on Paddy Soil Quality and Rice Growth (비산재로 제조한 비료가 논토양 질과 벼 생육에 미치는 영향)

  • Oh, Se Jin;Yun, Hyun Soo;Oh, Seung Min;Kim, Sung Chul;Kim, Rog Young;Seo, Yung Ho;Lee, Kee Suk;Ok, Yong Sik;Yang, Jae E.
    • Journal of Applied Biological Chemistry
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    • v.56 no.4
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    • pp.229-234
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    • 2013
  • Coal ash can be added to agricultural soils to increase the chemical properties of soil such as pH, cation exchange capacity and nutrient availability of - B, Ca, Mo etc-. Therefore, the main purpose of this study was to evaluate the feasibility of fly ash as a soil amendment in paddy soils. Selected fly ash was mixed with bentonite and calcium hydroxide at the ratio of 80:15:5 (w/w) and manufactured as a pellet type at the size of 10 mm. Field experiments were conducted to evaluate the effects of fly ash fertilizer on the soil quality and crop growth compare to the control (no fertilizer) and, - traditional fertilizer. Results showed that soil pH and organic matter in paddy soils after applying the manufactured fly ash fertilizer were not increased compared to the other two treatments. However, the concentration of available phosphate and silicate in paddy soils were higher than those of the control and traditional fertilization. With regard to crop growth, no significant difference was observed between three different treatments. However, the content of protein in the rice grain cultivated with the fly ash fertilizer was higher than in the rice cultivated by other two treatments. Overall, fly ash fertilizer could increase the concentration of available silicate and phosphate in the paddy soil and improve the rice quality. In conclusion, fly ash can be utilized in agricultural soils as soil amendment, especially in the rice paddy soil.

Evaluation of Solidified Fuel Value of Dairy Cattle Manure Digested by Semi-Dry Anaerobic Digestion Method (젖소분뇨 반 건식 혐기소화 잔재물의 고체연료화 가능성 평가)

  • Jeong, Kwang-Hwa;Kim, Jung Kon;Lee, Dong-jun;Cho, Won-Mo;Ravindran, B.;Kwag, Jung-Hoon
    • Journal of the Korea Organic Resources Recycling Association
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    • v.24 no.4
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    • pp.95-103
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    • 2016
  • The objective of this study was to investigate feasibility of semi-dry anaerobic digestion using dairy cattle manure and to evaluate solidified fuel value of semi-dry anaerobic digestate. To evaluate semi-dry anaerobic digestion using dairy cattle manure, 950 mL bottle type anaerobic reactor was set in the constant temperature room maintained at $35^{\circ}C$. To produce anaerobic digestate for making solidified fuel, acrylic cylindrical anaerobic digester(1,000 mm width ${\times}$ 450 mm height) was set in the constant room temperature to carry out batch test of semi-dry anaerobic digestion using same dairy cattle manure. Moisture content of dairy cattle manure and inoculum solution for anaerobic digestion were 80.64% and 96.83%, respectively. The dairy cattle manure and the inoculum solution was mixed by 1:1 ratio(v/v) for anaerobic digestion. Water content and VS/TS(Volatile Solids/Total Solids) of mixture of substrate and inoculum were 89.74% and 83.35%, respectively. In case of non-inoculated anaerobic digester, the biogas was not produced. By the semi-dry anaerobic digestion, the calorific value of the digestate was reduced by 20% compare to fresh dairy cattle manure. In other hand, ash content increased from 15% to 18.4%. The contents of Cr, Pb, Cd and S of pellet produced from anaerobically digested dairy cattle manure were not against the standard regulation for livestock manure solidified fuel. Therefore, it can be used as fuel that anaerobic digestate produced after semi-dry anaerobic digestion using dairy cattle manure.

Influence of Dissolved Ions on Geochemical Dissolution of Uranium in KURT Granite (KURT 화강암 내 우라늄의 지화학적 용출특성에 미치는 용존이온의 영향)

  • Cho, Wan Hyoung;Baik, Min Hoon;Ryu, Ji-Hun;Lee, Jae Kwang
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.16 no.3
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    • pp.281-290
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    • 2018
  • In order to understand the long-term behavior of radionuclides in granite environments, geochemical behavior characteristics of uranium in granitic host rock of KURT (KAERI Underground Research Tunnel) were investigated by dissolution experiment with different reaction time and solutions. In the dissolution experiment, significantly increased dissolution levels of uranium from granite powder samples were identified during the reaction time of 0~10 days for reaction solutions ($UD-CO_3$ and UD-Bg) containing a large amount of $CO_3{^{2-}}$. On the other hand, significantly increased dissolution levels of uranium were also identified for reaction solutions containing Na and Ca after 60 days. Dissolution of uranium continuously increased in reaction solutions of $UD-CO_3$ ($44.61{\mu}g{\cdot}L^{-1}$), UD-Bg ($41.01{\mu}g{\cdot}L^{-1}$), UD-Na ($26.87{\mu}g{\cdot}L^{-1}$), UD-Ca ($20.26{\mu}g{\cdot}L^{-1}$), UD-CaSi ($17.03{\mu}g{\cdot}L^{-1}$), and UD-Si ($10.47{\mu}g{\cdot}L^{-1}$) in the experimental period of ~270 days. However, after day 270, dissolution of uranium showed a decreasing tendency. This is thought to have occurred because existing uranium in granite samples reached the limit of dissolution by interaction with reaction solutions. Concentrations of dissolved uranium and points of maximum concentration value were found to differ depending on the $CO_3{^{2-}}$ presence in the mixed reaction solution and on the geochemical type of the water. It is estimated that differences in the reaction rate between the granite sample and the reaction solution are due to the influence of dissolved ions in the reaction solution.

Vegetation Succession and Vegetation Management of the Pinus densiflora S. et Z. Forest in the Beopjusa Area, Songnisan National $Park^{1a}$ (속리산국립공원 법주사지구 소나무림 식생천이와 식생관리 연구)

  • Lee, Kyong-Jae;Ki, Kyong-Seok;Choi, Jin-Woo
    • Korean Journal of Environment and Ecology
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    • v.23 no.2
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    • pp.208-219
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    • 2009
  • This study is to establish a management method for conservation through comparison and analysis on vegetation structures of Pinus densiflora forest around Beopjusa area for past 17-year. The spatial range of the study was $3.6km^2$ from maintenance office to Beopjusa area. The analysis results of the actual vegetation showed that the ratio of vegetation were composed of 64.7% of Pinus densiflora forest, 3.2% of mixed forest of P. densiflora and deciduous broadleaf trees and 5.9% of deciduous broadleaf tree community out of overall area, 360ha. The type of P. densiflora forest were categorized into four communities; community having high potential of succession, community having low potential of it, the community being in the process of succession and community being in the process of natural selection. The succession tendency was in order of the community having low potential of succession(P. densiflora forest), having high potential of it(P. densiflora forest which is deciduous broadleaf trees are dominating in sub-canopy layer), being in the process of succession(P. densiflora-Prunus sargentii and P. densiflora-Quercus serrata community) and being in the process of natural selection(Q. serrata-P. densiflora and Q. aliena-P. densiflora community). In terms of vegetation management, P. densiflora forest having high potential of succession was needed to remove deciduous broadleaf trees in the sub-canopy layer and the community being in the process of succession was required to be pruning the branch in the canopy layer. Lastly, the community being in the process of natural selection was suggested to let it be in succession, since it is hard to be in the status of P. densiflora Forest.

Effectiveness of Controling Micro Climate by the Pine (Pinus Densiflora) Forests of the Temple in Southeast Area of Korea (영남권 사찰림일대 소나무장령림의 미기후 조절 효과 연구)

  • Hong, Suk-Hwan;An, Mi-Yeon;Kang, Rae-Yeol;Choi, Song-Hyun
    • Korean Journal of Environment and Ecology
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    • v.34 no.4
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    • pp.294-303
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    • 2020
  • This study aimed to examine was conducted to the ability of microclimate control in old pine forests by surveying pine forest in Buddhist temples, where the pine forest are stably growing through active protection in the Gyeongnam region, and comparing variation characteristics of microclimate characteristics (temperature and humidity) and distribution of vegetation type. The study sites were pine forests protected well by Buddhist temples (Haein-sa, Beomeo-sa, Tongdo-sa, and Bulguk-sa) in the southeast region of Korea and thus known for stably growing young pine trees. According to the vegetation distribution status analysis, these pine forests did not have a high ratio of pine trees. Except for Tongdo-sa, the ratio of deciduous forest and mixed (deciduous and pine trees) forest had a much larger presence than that of pine forest. Measured data of microclimate showed that the Tongdo-sa area had significantly different characteristics compared to the other three areas. Tongdo-sa area showed a significantly higher diurnal range of temperatures and humidity than the other three areas, in both spring and summer. It is due to the difference in vegetation management. The forests around Tongdo-sa are mostly pine forests, except for the developed areas, while those in the other three areas have a dominant ratio of deciduous brad-leaved forests. Intensive control of pine forest is not effective in mitigating microclimate, i.e., temperature and air humidity. Stress caused by rising temperatures and decreasing air humidity is blamed for the decline of pine forests. Thus, the current active management of pine forests, such as the Tongdo-sa case, has been found to have a greater negative impact on the temperature and humidity stress. Therefore, we believe that a new change in forest management is necessary to increase the effect of mitigating the microclimate of pine forests.

The physiological characteristics of Pleurotus ferulae Lanzi (아위버섯균의 생리적 특성)

  • Kim, Dae-Sik;Chai, Jung-Ki;Wi, Kye-Moon;Yoon, Dai-Ryoung;Oh, Deuk-Sil;Chang, Kyoung Soo;Son, Han-Gil
    • Journal of Mushroom
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    • v.2 no.2
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    • pp.88-96
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    • 2004
  • This study was executed to decide the physiological characteristics of Ferule mushroom. Four strains of Ferule mushroom were tested to select a superior strain in its mycelial growth. The pertinent substrates, temperature and pH ranges for the growth of selected strain were determined. And then, the wood rotting ability and type of the Ferule mushroom were determined. The superior strain F-2 among four strains was selected, on the basis of its vegetative mycelial growth and density on agar media. Mycelial growth of F-2 was the best on MYPA among other tested synthetic or semi-synthetic media. The temperature range for pertinent mycelial growth was about $25{\sim}34^{\circ}C$ and best at $30^{\circ}C$. The optimum pH range on MYPA was 5.0~6.0. The mycelial growth was mostly stimulated by soluble starch at cont. 1% (w/w) and secondly, maltose among several carabon sources and by mixed solution of YE(0.25%) and ME(0.25%) but not by ME alone. Cell thining and erosion of Pinus rigida wood by the mycelia of Ferule mushroom were found only on a few cell but largely at wood block test, indicating that the softwood rotting ability of Ferule mushroom mycelia was not so good. The result of polarized light microscopy appeared that cellulose of some tracheides showing the S3 layer lost brifringence was degraded by Ferule mushroom. But only part of cellulose of P. rigida wood was degraded by Ferule mushroom, because most of wood cells continued to showing briefingence. A largely degraded ray parenchyma and longitudinal parenchyma cell and partly thinning and erosion of hardwood(Quercus serrata) cell was found and it indicates that the rotting ability of Ferule mushroom mycelia on hardwood was higher than on softwood. It could be concluded that the difference in the wood rot by Ferule mushroom between the hardwood and softwood was made by the difference of chemical constitutions between them, especially in the contents and the types of lignin. Ferule mushroom was considered as white rotter as a result of bavendam test, although more research should be required.

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Processing Conditions and Quality Stability of Frozen Seasoned Sardine Meat during Frozen Storage (냉동 정어리 조미육의 가공 및 저장중의 품질안정성)

  • LEE Eung-Ho;OH Kwang-Soo;AHN Chang-Bum;LEE Tae-Hun;CHUNG Young-Hoon
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.20 no.3
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    • pp.191-201
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    • 1987
  • Seasoned sardine meat was prepared to extend the use of sardine for human consumption, and processing conditions and storage stability of frozen seasoned sardine meat were studied during storage at $-20^{\circ}C$. The fish was beheaded, gutted and cleaned in a washing tank. The washed fish was then put through a belt-drum type meat separator which separates the flesh iron the bone and skin. Mechanically deboned fish meat was mixed with $20.6\%$ emulsion curd, $0.5\%$ table salt, $2.0\%$ sugar, $0.4\%$ sodium bicarbonate, $0.2\%$ polyphosphate, $0.1\%$ monosodium glutamate, $0.3\%$ onion powder, $0.1\%$ garlic powder, $0.1\%$ ginger powder, $3.0\%$ soybean protein and $0.1\%$. In sodium erythorbate. This seasoned sardine meat was frozen with contact freezer, packed in a carton box and then stored at $-20^{\circ}C$. The pH, volatile basic nitrogen, viable cell counts, peroxide value, carbonyl value, thiobarbituric acid value, taste compounds, fatty acid composition, salt extractable nitrogen, drip, texture, and color values of the products were determined during frozen storage. The results showed that lipid content in products could be controlled by using emulsion curd, and flavor and texture could be improved by adding spices and soybean protein, and lipid oxidation could be retarded by $0.1\%$ sodium erythorbate. Judging from the results of chemical experiments and sensory evaluation, the products can be preserved in a good quality for 120 days during frozen storage.

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Ecological Investigations on the Managed Forests in Northwestern Europe and Tree Seed-Orchard System (북구(北歐)의 우량임분(優良林分)의 생태(生態) 및 채종원(採種園) 체계(體系)에 관(關)한 연구(硏究))

  • Kim, Chi Moon
    • Korean Journal of Agricultural Science
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    • v.9 no.1
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    • pp.239-249
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    • 1982
  • The outlines of superior stands, including species mixed, age classes, canopies, and ecological conditions of the stands, were examined in the forests of west Germany, Sweden, and Netherland. The establishment schemes of tree seed orchards for the production of high genetic quality seed were also investigated in the present study. 1. The meteorological conditions, abundant in precipitation and high in relative humidity, prove it to be oceanic climate characteristics in the Scandinavia located in high latitude and north-western part of Europe. The photo periodical characteristics following to day-length and the frost times determine the patterns of tree growth and distribution as well as the tree adaptability due to bud-setting and bud-flushing in Sweden forest. 2. The European forests are generally characterized by dense multistoried forest type composed of upper stories of tall tree species such as Norway spruce, fir, Scots pine and beech, lower stories of shade tolerant poles and saplings of spruce, fir, beech, and floor vegetations covered with birch, oak and hornbeam etc. 3. The single tree selection method and group shelterwood method are commonly applied for silvicultural system but shelterwood method and clearcutting method practiced partially in limited area. Badischer Femelschlagbetrieb and Bayerischer Femelschlagbetrieb are popularized to the regeneration of Schwarzwald but selection method applied in part. 4. Tree cuttings are properly limited so as not to exceed annual increment volume for the sustained yield and the preservation of ecosystem in European forest management. Land preservation and recreation function are more interested with the promotion of wood production in the forest management. 5. Careful attentions are paid to the reforestation of the introduced exotic species, such as Douglas-fir, red oak, pines from America, Japanese larch, Italian poplar etc., with concern against the insect and pest damage, and the meteorological damage. 6. Some intensive studies on tree improvement, such as selection of plus tree, selection of plus stand for seed collection, provenance trial, progeny test of clone, hybrid seed orchard for clone complexing, are performed in the countries and the great part of the seed required for reforestation are supplied from the seed orchard established in Sweden and Netherland.

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