• Title/Summary/Keyword: Soil problems

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Survey on the Technical Status of Major Sericultural Farming Areas in Korea (잠업단지의 기술적실태에 관한 조사연구)

  • 김문협;김윤식;강석권
    • Journal of Sericultural and Entomological Science
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    • v.14 no.2
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    • pp.125-154
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    • 1972
  • The major purpose of this survey is to collect the related information on technical aspects for solving the problems which are facing producing farmers and regions, provide scientific facts to farmers related personals and institutions and aimed at contributing the development of sericultural sector in Korea. The results are as follows; (1) The area of mulberry field per a farmer which was selected as sample ranges from 3.0 to 370a with its average 45. 1a. And yet, the average of new cultivated areas is above than that of ordinary ones by 56.3 to 33.8a. The largest area is Honam hill area with 101. 1a and e smallest is Muzinzang with 20.8a. Shortly, a large number of farmer belongs to 11 to 50a with 66.5 per cent. (2) The ratio of clay and loam soils which are inadequte for growing of mulberry trees is 28.3 per cent and particulary high in new cultivated area with 36.2 per cent. And yet, base soil is occupied with 45 per cent of heavy clay and particularly even 54.2 per cent in new cultivated area. On the other hand, the number of areas which the contents of organic matters is relatively low, with 48.2 per cent is near the half, but the ratio of mulberry fields which seems to contain organic matters abundantly is only 7.2 per cent. (3) The varieties of mulberry trees are Ilgirae, Gaeryangseoban, Suwonsang No.4 and Nosang. The ,ratio of the varieties are 33.3%, 25.7%, 18.0% and 10.5%, respectively. Consequently the four varieties enumerated above occupies 93.5 per cent. (4) The mulberry fields are almost composed of exclusive mulberry fields and its ratio was 92.3 per cent. The number of planted trees per 10a arrange from 480 to 1,390 and its average is 846. But most of them nearly belong to 701 to 1,000 with 91.3per cent. (5) The second year's autumn after planting is generally adopted as the first harvesting season, and its ratio is 73.0 per cent, but autumn of the years and next spring are not few, and its ratio are 12.7 and 8.7 per cent. The first harvesting method is relatively normal with 88.8 per cent of ratio. From the viewpoint of harvesting method, picking leaves was applied with 97.7 per cent of ratio in young larvae rearing and picking shoot and picking shoot after harvest with branches were applied with 80.0 per cent of ratio in grown larvae rearing. The ratio of applying the harvesting method of picking leaves were 97.7 and 91.7 per cent in young larva and grown larva in autumn rearings. But there was also picking leaves absolutely with 7.1 per cent of ratio(Chunwon was 47 per cent) and yet, the farmers applying cutting before shooting in spring was no more than 17.8 percent.

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A Study on the Resettlement Policy for the Hwajeon-Farmers of Illegal Reclamation in Gangweon-do (강원도(江原道) 화전정리사업(火田整理事業)에 대(對)한 소고(小考))

  • Kim, Tong Soo
    • Journal of Korean Society of Forest Science
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    • v.22 no.1
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    • pp.7-17
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    • 1974
  • Eighty percent of Gangweon-Do area is mountain forests, and of all others this province has the largest number of "Hwajeon-farmers" (who illegally reclaim the mountain forests to do farming as long as the soil is fertile enough to yield profit, but when it fails, move to other places to repeat the same forest burning, causing tremendous forest damages). In 1965 a 7-year plan was mapped out to exterminate this gipsy-farmers only to be suspended in 1969 to give way to the stronger urge from the national security view-point to first displace those isolated farmers set in deep mountains. In the meantime an increased number of the Hwajeon-farmers burned the forests, working new havoc. To cope with the situation, the provincial government lounched another 4-year plan in 1973 and has been enforcing the resettlement policy with renewed enthusiasm. Whether the plan will succeed depends entirely on the authority involved can solve the problems listed below with regard to the Hwajeon-farmers who are to lose their only means of survival and move down to the low-lands: 1) Their living must be taken care of until they can have definite means of self-supporting. 2) They must be provided with the opportunity to work in connection with the government-sponsored labor programs. 3) Not only the public organizations but also the private firms must give them the priority to get work. 4) The rural revitalization movement must expand the self-help reconstruction projects to absorb their labor powers. 5) The Hwajeon-farmers themselves must have the spirit of self-help and self-supporting. 6) All the citizens in the province must receive and protect them with brethren love. 7) The function of the watch-posts against the Hwajeon-farmers must be strengthened again.

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Investigation on the Actual State of Grassland in Republic of Korea (국내 초지보유농가의 초지실태 연구)

  • Lee, Bae Hun;Kim, Ji Yung;Sung, Kyung Il;Kim, Byong Wan
    • Journal of The Korean Society of Grassland and Forage Science
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    • v.39 no.2
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    • pp.89-96
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    • 2019
  • This study was conducted to investigate 106 grassland farms in six provinces including Chungcheongbuk-do, Gangwon-do, Gyeonggi-do, Gyeongsangbuk-do, Gyeongsangnam-do, Jeju-do, and Jeollanam-do to present their problems and causes by surveying the actual state of grassland farms during three years(2014~2016). The grassland survey was divided into three categories; used as the perennial grasses and annual forage crops (Complied with Grassland Act), not used as the perennial grasses and annual forage crops (Not complied with Grassland Act) and failed to meet the farmer and some items are missing or inaccurate (Insufficient contents). Among the surveyed grassland farm, 68 farms (64.2 %) were complied with Grassland Act but 30 farms (28.3 %) were not complied with Grassland Act. Especially, the 8 farms (26.7 %) not complied with Grassland Act used the grassland as other purposes such as tree growing, golf club and swine farm etc.. Therefore, strict on-site investigation by local governments is required to prevent the grassland from being used by illegal purposes. And there's a strong likelihood that 5 farms (62.5 %) avoided the survey violate the positive law. Grassland grades used by the local administrative agencies were not influenced by the factors affecting the yield (existence and non-existence of overseeding and fertilization by grassland grade, soil pH and organic matter content). This results suggest that there is a fundamental problem on the current grassland grade system based on the yield and the irregular time of investigation and lack of on-site investigation are another causes for inaccurate grassland grade. Therefore, the new method evaluating grassland grades which is not based on yield and the thorough on-site investigation by local administrative agencies are necessary when the grassland grade is evaluated.

The Demand Analysis of Water Purification of Groundwater for the Horticultural Water Supply (시설원예 용수 공급을 위한 지하수 정수 요구도 분석)

  • Lee, Taeseok;Son, Jinkwan;Jin, Yujeong;Lee, Donggwan;Jang, Jaekyung;Paek, Yee;Lim, Ryugap
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.12
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    • pp.510-523
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    • 2020
  • This study analyzed groundwater quality in hydroponic cultivation facilities. Through this study, the possibility of groundwater use was evaluated according to the quality of the groundwater for hydroponic cultivation facilities. Good groundwater quality, on average, is pH 6.61, EC 0.27 dS/m, NO3-N 7.64 mg/L, NH4+-N 0.80 mg/L, PO4-P 0.09 mg/L, K+ 6.26 mg/L, Ca2+ 18.57 mg/L, Mg2+ 4.38 mg/L, Na+ 20.85 mg/L, etc. All of these satisfy the water quality standard for raw water in nutrient cultivation. But in the case of farmers experiencing problems with groundwater quality, most of the items exceeded the water quality standard. As a result of the analysis, it was judged that purifying groundwater of unsuitable quality for crop cultivation, and using it as raw water, was effective in terms of water quality and soil purification. If an agricultural water purification system is constructed based on the results of this study, it is judged that the design will be easy because the items to be treated can be estimated. If a purification system is established, it can use groundwater directly in the facility and for horticulture. These study results will be available for use in sustainable agriculture and environments.

The Diaspora Narrative and Aesthetics in Handol's Tarae (한돌 타래의 디아스포라 서사와 미학)

  • Shin, Sa-Bin
    • Journal of Popular Narrative
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    • v.26 no.3
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    • pp.189-219
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    • 2020
  • This study is an analysis of Handol Heung-Gun Lee's Tarae, which is a coinage combining the Korean words for "playing an instrument" and "song", in terms of narrative and aesthetics. The components for analysis are the phenomena and nature of binary oppositions between nature and human beings, between alienation and interest, between division and unification, and between diaspora and people of the national community. Tarae in the period from the late 1970s to the early 1990s described the experience of pain and loss from non-resistance and disobedience in protest against social problems that emerged during the era of miliary dictatorship, such as industrialization, urbanization, reckless development, Westernization, university-oriented education, the gap between rich and poor, human alienation, and the conflicts arising from the division of the nation. After Handol overcame the lack of creative motivation with self-reflection and effort, Tarae took the form of a diaspora epic meta-narratives integrating the "sound of nature and his true nature" and "the awareness of diaspora and the spirit of the Korean people". The epics of the homeland, the national soil and the people, which began with "Teo", became more intense in terms of a sense of diaspora as they shifted their focus from an origin to a path with "Hanmoejulghi" as the turning point. Handol seeks inspiration in the source of narrative rather than in music. His Tarae focuses on "adding rhythm for lyrics". For this reason, the semiotic features of Tarae have a limitation in that its extrinsic phonology is simple even if its intrinsic meaning (i.e., emotion of sadness) is profound and subtle. In order to elicit sympathy from the audience and impress them, it is necessary to strike a balance between the implicit (semantic) part and the explicit (phonological) part. To share the emotion of sadness with more people, it is necessary to strengthen phonological elements. Sympathy for sadness and deep impression on the audience are more often induced by the mood of similar sentiments than by the stories of the same experience. The aesthetics of sadness in Tarae began with the narratives of past experience which were expressed in the contexts of loss, loneliness, and poverty that Handol had experienced since childhood. However, the aesthetics of sadness, deepened over the period of a long hiatus in Handol's career as a composer, formed the narratives of ultimate salvation, embodying even the diaspora experience of others (e.g., displaced people, overseas adoptees, ethnic Koreans in Russia, victims of Japanese military sexual slavery, etc.). This gave Tarae the potential to go beyond the limits of the ethnic group of Korea. Tarae, as a "dispersed sound", can benefit from the appeal of deep sadness at the point of contact with other forms of world music. It may form a global diaspora discourse because Tarae is oriented towards interculturalism rather than anti-multiculturalism. The future challenge and goal of Handol's Tarae would be to continue to find areas of sympathy and broaden the horizon of awareness as diaspora music.

Study on the Herb Remedies of ENT, Eyes, Teeth and Skin Problems (이비인후, 안, 치아 및 피부증상의 민간요법에 관한 고찰)

  • Cho, Kyoul-Ja;Kang, Hyun-Sook
    • Journal of East-West Nursing Research
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    • v.1 no.1
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    • pp.50-71
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    • 1997
  • The intention of this study is to apprehend the con. tents and methods of herb remedies that are commonly conducted when there are health-problem cases of ENT, eyes, teeth and skin. Methods of this study are divided into two stages : 1) For a period of six months from December 1994 to June 1995, some 40 persons who are believed to be well versed with herb remedies have been randomly chosen, and we made a survey on herb remedies by symptoms: and 2) we have endeavored to make their grounds evident through the studies on literatures with the focus on the basic data collected. Their results are as follows: 1) When one feels a pain in ears, such herb remedies are employed as pouring the vapor into ears, which is made by steaming Alaska pollack, or as applying or wiping with the juices of radish or the ginkgo, or' alum. Applying the radish juice is effective for sterilization and fever removal: and applying the ginkgo juice is effective for cleanliness. But, plastering alum, sesame oil or castor oil, or pouring the vapor of Alaska pollack into ears are perhaps effective but do not have any pharmacologic grounds. 2) When one bleeds at the nose, such kinds of herb remedies are applied as stimulating nose or head with cold water, pressing nose or ridge of nose, or filling up nares with mashed mugworts. In addition, they have utilized garlic or leeks. Such methods as stimulating with cold water or just pressing nose and ridge of nose is based on reasonable grounds, i.e. vasoconstriction and vascular compression ; and applying mashed garlic on the sole of foot is good for the circulation of Qui ; and the use of mugworts and leeks is based upon the pharmacological function of hemostasis. 3) When one feels a sore throat such kinds of herb remedies are employed as gargling or rinsing throat with brine, drinking hot gruel or water, or drinking the juice of mugwort, radish, ginger or Chinese quince. Gargling with brine or drinking the juice of mugwort, radish or ginger is based upon the pharmacological function of pain alleviation, fever removal, and detoxication. 4) When a boil is formed in mouth, such herb remedies are applied as spreading honey, brine or alum water, and taking gall nut, Chinese matrimony vine, lotus root, etc, for drugs. Spreading honey, brine or water that is made by infusing gallnut, Chinese matrimony vine, lotus root is based upon such functions as hematosis, astriction, antibacterial, and antiphlogistic, Alum, eggplant and licorice are said to be effective, but their pharmacological effects have no grounds. 5) When one has conjunctivitis such herb remedies are commonly applied as irrigation with brine and dropping breast milk in eyes. Moreover, such other drugs are used as plantain. shepherd's purse, and purslane, etc. The use of brine, breast milk, plantain, shepherd's purse and purslane is based upon such functions as sterilization, antiphlogistic, disinfection and pain relieving. Eriocaulon sieboldianum, bean stem, bean pod and narcissus leaves are said to be effective, but their pharmacological action have no basis. When one has a stye, such herb remedies are applied as extracting eyelashes, stimulating by a massage of middle finger, third finger or big toe, as well as sear ing with a heated bamboo comb that is fine-toothed. Other than these, plantain and nightshade's nuts are used as drugs for it. Extracting eyelashes corresponds with exclusing suppurative node and draining the stye of pus ; and the use of plantain is based upon disinfection: and nightshade's nuts are said to be effective, however, their pharmacological action has no grounds. 6) For a treatment of toothache, such herb remedies are commonly employed as rinsing mouth with brine and holding cold water or gasoline in the mouth ; and as the drugs that are believed to be effective have been Welsh onion, ginger and castor-oil, plant, etc. The use of Welsh onion is based upon pain killing, antiinflammatory actions, and the use of ginger is based upon detoxication and disinfection ; and seeds of castor-oil plants are said to be effective, but they have no pharmacological basis. 7) When one has hives, such herb remedies are commonly applied as rubbing burned straw in affected parts, exposing to its smoke, rubbing with salt, sweeping down with a broom, and spreading and drinking boiled water of trifoliate orange. The use of cassia tora seeds, walnut, aloe and radish is said to be effective. The use of cassia tor a seeds has the functions of intestinal order, anti-paralysis, etc. The use of walnut has resulted in an increase of blood by invigorating spirits ; and the use of aloe is based upon disinfection, antibiotic, anti-salt, antihistamine and detoxication action. But, the effects of radish juice and straw's smoke have no pharmacological grounds. 8) When one gets a boil, such herb remedies are commonly used as applying a plaster, paste of flour mixed with yolk, soy sauce or honey, as well as spreading pounded elm tree. Other remedies that have been said to be effective are ; heating with mugwort, brine, wild rocambole, aloe, onion, squid's bone, etc. The use of mugwort is based upon pain killing, astringent antiinflammatory and tranquility. Wild rocambole is based upon the generation and maintenance functions of cell-joining textures ; elm tree upon antiphlogistic ; aloe upon fever removal and antiphlogistic ; onion on pain killing, fever removal, antiphlogistic and tranquility ; squid's bone on astriction: and brine or vinegar on sterilization. Pine resin and gardenia seed are said to be effective, but they have no pharmacological basis. 9) When one cuts his skin, such herb remedies are commonly employed as spreading mugwort's juice or squid's bone powder, or pressing the wounds. In addition, kalopanax, onion and fine soil are employed. The use of mugwort, kalopanax and squid's bone is based upon such functions as hemostasis, sedation, pain killing, antibacterial ; and fine soil is said to be effective, but it has no pharmacological basis. 10) When one suffers from whitlow, such herb remedies are commonly utilized as heating with boiled soy sauce, spreading soybean paste, or dipping into eggs, etc. Other drugs that have been employed are onion root, brine, eggplant, potato, loach, etc. The use of onion is based upon pain killing and antiphlogistic functions ; and that of brine upon antiphlogistic function. The use of soy sauce or soybean paste, fomentation, eggplant, potato and loach is said to be effective, but it has no pharmacblogic ground. 11) For the treatment of frostbite, such herb remedies are commonly used as dipping the affected part into frozen soybean sack, using boiled water of eggplant stem, garlic caulis, onion, hot pepper, caulis. Onion is based upon antiphlogistic and tranquility actions garlic upon disintection, metabolic exacerbation, tonic and aphrodisiac actions and the use of eggplant and hot pepper is based upon help blood circulation, dissolution and excretion of waste matters in vein. 12) For the treatment of burn, such herb remedies or drugs are commonly used as cleansing with Korean gin, spreading eggs, cleansing with cold water and soap water ; and as brine, cactus, moss, soybean paste, oil, etc. The cleansing with Korean gin, cold water, soap water, brine, vinegar is based upon cleaning and sterilizing functions ; and the use of cucumber is based upon nu. trition provision, and strengthening of resisting power by adjustment of metabolism. The use of potato, cactus, moss, oil and eggs is said to be effective, but their phamacological functions are not clarified. In view of the above results, we can realize that the drugs that have been employed in herb remedies are quite diverse. However, in regard to majority of herb remedies that have been employed by symptoms, the pharmacological functions of their drugs have not been clarified, and they are merely known as effective. Furthermore, they have not been recorded in the literature as yet ; and we confirm that there have been many herb remedies that were executed without the proper knowlege of their effects. It is now our view that the results of this survey may be utilized for consulting data in regard to the use of herb remedies.

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The Status, Problems and Countermeasure of Direct Rice Seeding in Honam Province - On Weed control - (호남지방(湖南地方) 직파재배(直播栽培)의 현황(現況), 문제점(問題點) 및 대책(對策) - 잡초방제적(雜草防除的) 측면(側面)에서 -)

  • Ryang, Hwan-Seung;Kim, Jong-Seog
    • Korean Journal of Weed Science
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    • v.12 no.3
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    • pp.271-291
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    • 1992
  • This study was conducted to survey the situation of direct rice seeding in Honam province in Korea to investigate problems and seek countermeasure of weed control in direct rice seeding. The total area of direct rice seeding in the south-western part of Korea (Chonbuk, Chonnam, and Chungnam) was 1650.8ha (732.1ha for direct seeding in dry field and 918.7ha for direct seeding in flooding field) in 1992. The followings are summary of the study. 1. In case of direct rice seeding in dry field, butachlor EC and G at 3 to 5 DAS was mostly selected by farmers to control weeds in dry field. Benthiocarb or chlornitrofen was also used in few cases. At 10 to 14 DAS just before rice emergence, tank misture of butachlor EC and paraquat was treated by some farmers. At 35 to 40 days, after flooding mixture of sulfonylurea derivatives was sequentially applied. Surviving weeds including barnyardgrass were finally controlled by mixture of bentazon+quinclorac WP foliage application. 2. In case of direct rice seeding in flooding field, weed control were mostly unsuccessful partially due to wrong selection of herbicide and missing the optimum application time. Three relatively successful weed control in the survey were summarized as follows. 1) Oxadiazon EC, butachlor or benthiocarb were treated just after puddling(5 to 7 days before seeding). then mixture of bentazone+quinclorac WP or sulfonylurea derivatives was sequently applied to control remaining weeds at 20 days after seeding. 2) Mixtures of bensulfuronmethyl+dimepiperate G, pyrazosulfuronethyl+molinate G, or bensulfuronmethyl+mefenacet+dymron G were applied at 11 days after puddling when barnyardgrass were at 2.0 leaf stage. Phytotoxicity was not found in case of mixture of bensulfuronmethyl+dimepiperate G but found in the other two cases but disappeared later. 3) Mixtures of bensulfuronmethyl+quinclorac G., pyrazosulfuronethyl+quinclorac G or betazone and quinclorac G were treated after 18 to 20 days after puddling when barnyardgrass was within 3.0 leaf stage. It showed good weed control in both annuals and perrenials without phytotoxicity. On the contrary, other sulfonylurea derivatives such as middle periodic herbicide showed poor weed control against barnyardgrass, so that sequential treatment of bentazone+quinclorac WP mixture was required. 3. Herbicidal characteristics and optimum application time of 45 rigistered herbicides in Korea were analyzed to discover new substitute for quinclorac mixture, that showed excellent weed control against barnyardgrass at its 3 leaf stage or older. The analysis revealed that 70% of herbicides were for preemergence and the others were post periodic herbicide. Most farmers favor to apply herbicide when rice seedlings completely rooted, at this time barnyardgrass are at 2.5-3.0 leaf stage. Therefore herbicide of which optimum application time had long is required. In this study. 6 middle periodic herbicides among sulfonylurea derivatives and 2 quinclorac mixture were selected and evaluated their weeding spectrums at different leaf stage of barnyardgrass in both soil application in flooding condition and foliage application in dry paddy field. The order of weeding spectrum in magnitude was as follows : bentazone+quinclorac WP> bentazone + quinclorac G>bensulfuronmethyl + quinclorac G>pyrazosulfuronethyl + quinclorac G> pyrazosulfuronethyl + Molinate G>bensulfuronmethyl + mefenacet + dymron G>bensulfuronmethyl + mefenacet G>bensulfuron methyl+benthiocarb G. The above results coincided with that of the survey. In conclusion, there is no proper substitute for quinclorac mixrure, which can control barnyardgrass at 3.0 leaf stage or even older. Therefore quinclorac should be supplied continuously to farmers in order to anchor direct rice seeding in Korea. Author suggested the followings to eastablish direct rice seeding technology effectively and quickly : 1) A tentatively named "The research committee for direct rice seeding" which was composed of farmers. researchers and goberment. should be eastablished to cooperate effectively. 2) Development of a pricise direct rice seeding machine for both dry and flooding paddy field. which is workable regardless of condition and varieties of seeds. 3) Study on protecting rice seed and seedling from sparrows. 4) Systematic studies of weed control techniques in direct rice seeding to standardize herbicide application. 5) Studies on farm-land reformation. techniques of precise land preparation. and direct rice seeding using an airplane.

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Geochemical Equilibria and Kinetics of the Formation of Brown-Colored Suspended/Precipitated Matter in Groundwater: Suggestion to Proper Pumping and Turbidity Treatment Methods (지하수내 갈색 부유/침전 물질의 생성 반응에 관한 평형 및 반응속도론적 연구: 적정 양수 기법 및 탁도 제거 방안에 대한 제안)

  • 채기탁;윤성택;염승준;김남진;민중혁
    • Journal of the Korean Society of Groundwater Environment
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    • v.7 no.3
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    • pp.103-115
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    • 2000
  • The formation of brown-colored precipitates is one of the serious problems frequently encountered in the development and supply of groundwater in Korea, because by it the water exceeds the drinking water standard in terms of color. taste. turbidity and dissolved iron concentration and of often results in scaling problem within the water supplying system. In groundwaters from the Pajoo area, brown precipitates are typically formed in a few hours after pumping-out. In this paper we examine the process of the brown precipitates' formation using the equilibrium thermodynamic and kinetic approaches, in order to understand the origin and geochemical pathway of the generation of turbidity in groundwater. The results of this study are used to suggest not only the proper pumping technique to minimize the formation of precipitates but also the optimal design of water treatment methods to improve the water quality. The bed-rock groundwater in the Pajoo area belongs to the Ca-$HCO_3$type that was evolved through water/rock (gneiss) interaction. Based on SEM-EDS and XRD analyses, the precipitates are identified as an amorphous, Fe-bearing oxides or hydroxides. By the use of multi-step filtration with pore sizes of 6, 4, 1, 0.45 and 0.2 $\mu\textrm{m}$, the precipitates mostly fall in the colloidal size (1 to 0.45 $\mu\textrm{m}$) but are concentrated (about 81%) in the range of 1 to 6 $\mu\textrm{m}$in teams of mass (weight) distribution. Large amounts of dissolved iron were possibly originated from dissolution of clinochlore in cataclasite which contains high amounts of Fe (up to 3 wt.%). The calculation of saturation index (using a computer code PHREEQC), as well as the examination of pH-Eh stability relations, also indicate that the final precipitates are Fe-oxy-hydroxide that is formed by the change of water chemistry (mainly, oxidation) due to the exposure to oxygen during the pumping-out of Fe(II)-bearing, reduced groundwater. After pumping-out, the groundwater shows the progressive decreases of pH, DO and alkalinity with elapsed time. However, turbidity increases and then decreases with time. The decrease of dissolved Fe concentration as a function of elapsed time after pumping-out is expressed as a regression equation Fe(II)=10.l exp(-0.0009t). The oxidation reaction due to the influx of free oxygen during the pumping and storage of groundwater results in the formation of brown precipitates, which is dependent on time, $Po_2$and pH. In order to obtain drinkable water quality, therefore, the precipitates should be removed by filtering after the stepwise storage and aeration in tanks with sufficient volume for sufficient time. Particle size distribution data also suggest that step-wise filtration would be cost-effective. To minimize the scaling within wells, the continued (if possible) pumping within the optimum pumping rate is recommended because this technique will be most effective for minimizing the mixing between deep Fe(II)-rich water and shallow $O_2$-rich water. The simultaneous pumping of shallow $O_2$-rich water in different wells is also recommended.

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