• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.22 no.2
• /
• pp.139-147
• /
• 2021

Livestock manure is used as an organic fertilizer to replace chemical fertilizers after sufficient fermentation in an aerobic bioreactor. On the other hand, liquid manure disposal problems occur repeatedly because soil spraying is restricted during the summer when the crops are growing. To use liquid fertilizer (LF) as an additional nutrient source for crops, it is necessary to reduce the amount of suspended solids (SS) in the liquid fertilizer and secure stability problems against pathogenic microorganisms. This study examined the effects of the simultaneous SS removal and E.coli sterilization in the LF using the microbubble (MB) generator (FeMgO catalyst insertion). The remaining SS were further removed using the integrated microbubble and microfilter system. During the floating process in the MB device, the SS were removed by 57.9%, and the coliform group was not detected (16,200→0 MPN/100 mL). By optimizing the HRT of the integrated system, the removal efficiency of the SS was improved by 92.9% under the 0.1h of HRT condition. After checking the properties of the treated LF, 64.5%, 70.1%, 54.9%, and 51.5% of the TCOD, SCOD, PO4-P, and TN, respectively, were removed. The treated effluent from such an integrated system has a lower SS content than that of the existing LF and does not contain coliforms; therefore, it can be used directly as an additional fertilizer.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.36 no.6
• /
• pp.576-585
• /
• 1991

General procedures of seed preparation as conventional guide had been established in China before most of Korean literature documented them. ‘Chwijongbeob’ (method of seed select) was to select good quality of seeds and to discard the rest. In ‘Seonjongbeob’ (method of seed grading) although China employed only ‘Sooseonbeob’ (method of seed select with water), but seeds were selected in order of selection of seeds by winds, selection of seeds by sieve and selection of seed with water in Korea. As compared with the recent techniques, those methods were perfect techniques for selection of good quality seeds of rice, except for method of seed selection by salt water was developed. The method for measurement of seed moisture, and for measurement of melted snow, spoiled urine and extracted juice by boiling water with the bone of livestock were originated from ancient China. The farming books in Korea were more or less followed the above methods. However, these techniques were complicated and impractical interms of validity and rationality. Also, it is judged that these tchniques are more appropriate in dry areas and alkaline soil of China rather than in Korean conditions. The plowing is a work to begin farming, and is operated for air ventilation between atmosphere and earth. Also, this techniques was adopted in the farming books from the early to the late Chosun dynasty without changes. Fields were deep-plowed in the first, in fall (or in spring) and for cultivation, and were shallow -plowed in the second, in spring (or in summer) and in intertillage. The former was for water reserve and land preparation, and the later was for weed control with intertillage. However, plowing in fall which was different from fallowing in dry areas, was recommended in Korea (Jikseol). but was not practiced in Sejongsilrok. This was changed with time, and plowing for cultivation in Korea was interrelated with use of green manure crops, method of plowing of upseting plough, method of manure practice and sometimes dry plowing. In addition, until the 15th century method of using a kind of plowing-tool made of log as farm tools was created to support reclamation for enlargement of farm land in mountaineous and coastal areas. For desolate farm lands by many internal and external disturbances, one tried to recover yield ability by increasing labor productivity from the 17th or 18th century. To do this, ‘Banjongbeob’ (culture method by upset plowing weed control) and ‘Hwanubeob’(culture method by firing weed control) which were cultural methods of ancient China were readapoted but the results were not clearly informed. Also, the reality of those was reexamined in the end of the Chosun dynasty.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.3 no.2
• /
• pp.100-111
• /
• 1983

The research results reported herein had the objectives to understand and analyze the present problems of saemaeul woodland joint cattle grazing system in Kang Won Do and to take steps of improvement. The study results on actual management conditions, problems analyzed and improvement plan of total 208 joint cattle grazing area which was established 105 area in 1981 and 103 area in 1982 were summarized as follows: 1. the effectiveness of joint cattle grazing projects 1) Average daily weight gain of cattle during joint cattle grazing period was 0.4kg, showing higher daily than the conventional feeding of 0.33kg. 2) Increase of total farm income over the conventional feeding system were \1,031,357,320 during the grazing period from May to October in 1982 by adapting the 208 joint cattle grazing system, of which effectiveness of weight gain was \293,075,300 and labor saving was \543,838,750. 3) According to the results of questionaire investigation from 208 joint cattle grazing area, effectiveness of joint cattle grazing system over the conventional system were (1) labor saving, (2) feed cost saving, (3) reduced diseases, (4) increase of number of feeding, (5) inspiration of joint endeavor, (6) effect of more gain, (7) easiness of feeding and feed cost savings. 2. Problems of joint cattle grazing system. 1) Shortages of grass were a problem at second year of joint cattle grazing period due to the low regrowth rate of wild grass. 2) Proper land for woodland joint cattle grazing is belonging to land of Government ownership and it is very hard to get the permission from office of forestry for cattle grazing purpose. 3) It is also difficult to find a proper time of breeding in grazing area by the difficulty of estrus detection. 4) There are a difficulty to give a proper vaccination and medical examination for the grazing cattle. 3. Improvement plans for woodland joint cattle grazing projects. 1) Obtain sufficient roughages by hoof cultivation and oversowing pasture from the second year of joint cattle grazing period. 2) In order to increase the beef production and to use for a calf production area, Government should arrange that all proper grazing land of Government owned in Kang Won Do convert into woodland joint cattle grazing area. 3) Make a good reproductive record by mixed grazing with a excellent breeding cow in a remote area. And carry out the collective artificial insemination with synchronous puberty induced by injection of puberty stimulation hormone. 4) Make a preventive injection for blackleg, twice medication of fasciola hepatica in a year, and spray and medication of tick insecticide. 4. A policy towards upbringing of woodland joint cattle grazing area. 1) Government should thoroughly investigate about a proper land for woodland joint cattle grazing from all forests. 2) When the area is suitable for the woodland joint cattle grazing, though it is national forest or restricted area, government should make it possible to establish a grazing area. 3) On the proper land foe joint cattle grazing in the remote place, Government should support for the road construction and electric fence equipments by using of national funds. 4) There should be an administrative consideration for well promotion of the project that make woodland joint cattle grazing suitable to the characteristics of Kang Won Do. 5) In order to improve the reproduction record, Government should reform the insufficiency of artificial insemination in the joint cattle grazing area. 6) In order to maintain a proper price of cow, Government should carry out the price plan. 7) When there is any request for grassland formation in the woodland joint cattle grazing area, Government should permit it with preference.

• Journal of Bio-Environment Control
• /
• v.21 no.3
• /
• pp.192-198
• /
• 2012

Experiments were conducted to investigate the optimum concentration of nutrient solution in hydroponics for strawberry 'Ssanta' bred at Gyongsangbuk-do Agricultural Research & Extension Services. Nutrient solutions for strawberry, which made by Yamazaki, were supplied EC (Electrical Conductivity) 0.6, 0.8, 1.2, and $1.8dS{\cdot}m^{-1}$ after planting on cocopeat medium during experiment period. Growth of shoot of strawberries did not show statistical differences among treatments. Fruit length showed the longest in EC $0.8dS{\cdot}m^{-1}$ in all clusters. In the second flower cluster, fruit length showed longer in EC 0.8 and $1.2dS{\cdot}m^{-1}$ than EC 0.6 and $1.8dS{\cdot}m^{-1}$. In the third flower cluster, it showed the longest in EC 0.8 and $1.2dS{\cdot}m^{-1}$, followed by 0.6 and $1.8dS{\cdot}m^{-1}$. The longest was in EC $0.8dS{\cdot}m^{-1}$ and the shortest in EC $1.8dS{\cdot}m^{-1}$ in the fourth flower cluster. Fruit diameter did not show significant differences among treatments, but longest in EC 0.8 and $1.2dS{\cdot}m^{-1}$ in all clusters. The heaviest mean fruit weight appeared in EC $0.8dS{\cdot}m^{-1}$ in all flower clusters. And heavier in EC $1.2dS{\cdot}m^{-1}$ in the second and third clusters. Also the weight was significantly light in plants grown in EC 0.6 and $1.8dS{\cdot}m^{-1}$ in the second and third cluster. Soluble solids of fruit was the highest in EC $0.6dS{\cdot}m^{-1}$ in all clusters. As the results, we came to the conclusion that the optimum EC for strawberry 'Ssanta' was EC $0.8{\sim}1.2dS{\cdot}m^{-1}$ in this experiment.

• Journal of Sericultural and Entomological Science
• /
• v.47 no.2
• /
• pp.68-77
• /
• 2005

A characteristic of subtropical zones region MK-T2 compares with an gaeryangppong, and the 9-10 schedule the times when a leaf blooms to are fast, and ratio that a branch edge by the colds becomes lean showed 5.7%, and a growth of the new branch which went out delivers 67.2 cm, mulberry loaves of the new branch which went out, and 18.6, a form of a leaf is the 1.10 that length of a leaf grew more a bit than width of a leaf up. Thickness of a leaf is $228.2{\mu}m$, and an area is more similar than gaeryangppong as $225.6cm^2$. in plant taxonomy, the hair whom the style exists short with 0.7 mm, and go to the pistil head inside so as to be rare is distributed, and belong to Dolichostylae Pubescentes. The new branch cutting which executed without remedy processes was independent of a thickness of a case branch, and the form and 100% root was said, and an gaeryangppong compared with the fact that 10% root went out of 15 mm ideal, and was excellent very, and looked, a root went out a root the soil and water, all showed a characteristic to go out at central of a branch bases at 45% ratio. Length was 24.6 mm, and were water rate 78.8%, and mulberry of MK-T2 was carrying together sweetness and acidity to pH 4.7 while, besides, arrival was 19.21 Brix%. A larva period and pupa ratio, cocoon thickness ratio are almost similar to gaeryangppong, or weight of one cocoon, cocoon thickness, 20,002 cocoon quantity shows some results to drop, and be soft of a leaf, and feed value certifications are comparatively top-ranking. As a result of having analyzed amino acid of the 3rd day of 5th silkworm larva which bred to MK-T2, a collation absorbing an gaeryangppong went, and looked, but compared with a collation in case of tests to eat MK-T2, and looked, and the lie collations were not detected a difference at Leu, but MK-T2 tests were detected mutual almost similar amino acid creation. medical efficacy of the 3rd day of 5th silkworm larva ethanol extract which bred to MK-T2 and black results, histologic a case did not appear at HE dyeing about the kidney organization which extracted form the rats which ate a silkworm ethanol extract and dyeing all chemical organization immunity, and one step protein revelation became lower with almost unidentified levels.

• Korean Journal of Weed Science
• /
• v.12 no.3
• /
• pp.271-291
• /
• 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.