• The Korean Journal of Malacology
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• v.15 no.1
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• pp.31-39
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• 1999

This study was aimed to describe the population dynamics and secondary production of Tapes philppinarum on Chohwa and Toksan tidal flats in Kwangyang Bay, from June 1994 to July 1995. The size distributions in shell length showed bimodal patterns from June 1994 to April 1995. Thereafter the distribution changed to the passage of time, indicating an increase in shell length. The mean densities decreased gradually with month. Chohwa A sustained highestdensity, followed by Chohwa B, Toksan C, and Toksan D. The recruitment of new year class occurred first on the upper tidal flat, and then moved to the lower tidal flat. The mean biomass in flesh dry weight of each year class increased in spring just before the spawning period, and thereafter decreased progressively. Annual mean biomass wasrecorded as 170.7 g m$\^$-2/ at Chohwa A, 220.7 g m$\^$-2/ at Chohwa B, 21.8 g m$\^$-2/ at Toksan C, and 45.2 g m$\^$-2/ at toksan D. Annual productions of Ruditapes philippinarum were estimated as 259.72 g m$\^$-2/ yr$\_$-1/ at Chohwa A, 359.79 g m$\^$-2/ yr$\_$-1/ at Chohwa B, 45.02 g m$\^$-2/ yr$\_$-1/ at Toksan c, 68.88 g m$\^$-2/ yr$\_$-1/ at Toksan D. Annual productions were much higher on Chohwa tidal flat than those on Toksan tidal flat. While P:B ratio were higher on Toksan tidal flat as 1.70 than those on Chohwa tidal flat as 1.58. In conclusion, the Chohwa tidal flat showed higher biomass and producion of Ruditapes philippinarum, whereas the Toksan tidal flat showed higher P:B ratio. The total amount of potential food might influence on the density, biomass nad produciton, whereas the amount of food and space per individual might influence on the growth rate and P:B ratio.

• Asian Journal of Turfgrass Science
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• v.23 no.1
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• pp.1-8
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• 2009

This study was conducted to investigate the effect of rainfall, irrigation and fertilizer application on water qualities of pond in golf course from May in 2007 year to November in 2008 year. For survey of water quality, it was sampled at $10{\sim}12$ sites(irrigation site 2, drainage site 3, and hazard site $5{\sim}7$) of SKY72 G.C and evaluated with analysis items such as pH, electrical conductivity(EC), DO, SS, T-N, $PO_4$-P, K, Ca, Mg, Na, SAR, BOD and COD. Results obtained were summarized as follows: The value of pH, EC, DO, T-N, P04-P, K, Ca, Mg, Na and SAR was in dry season, but those of SS, BOD and COD in the rainy season. N and P concentration of pond water showed $1.2{\sim}28.8mg/L$ and $0.005{\sim}0.172mg/L$, respectively, and so it was higher than eutrophication level of lakes and marshes recommended by the Ministry of Environment in Korea. As a reault of correlation analysis, EC in the water was significantly(P<0.01) related items such as K, Ca, Mg, Na, SAR and salinity, and SS significantly(P<0.05) BOD and COD. In comparison with a corelation between respective analysis items and rainfall amount, SAR was significantly(P<0.01) positive but T-N negative(P<0.01). As compared with corelation between respective items and irrigation amount, pH was significantly(P<0.01) positive but T-N(P<0.05) and BOD(P<0.01) negative. When it was applied to N, $P_2O_5$ and $K_2O$ in golf course, N and $K_2O$ significantly affected water qualities of pond(P<0.01). These results suggested that a pond water in golf course was affected by the fertilizer application, rainfall and irrigation and EC was adequate monitoring indicator for the evaluating water quality of pond by chemicals influent.

• Journal of Yeungnam Medical Science
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• v.8 no.2
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• pp.174-184
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• 1991

To determine the incidence rate of accidents and its associated factors, a prospective survey was carried out in a rural area of a total of 1,360 residents for 1 year from January 1 to December 31, 1988 in Shin-am Ri, Jungdong Myun, Sangju Kun, Kyungpook Province. Data for accidents were collected by the community health practitioner who is working at Primary Health Post in Shin-am Ri. A total number of accident cases was 85 among 1,360 persons during one year study period, and annual incidence rate was 62.5 per 1,000 persons. The highest incidence rate of accident was observed in the age group of 30-39 was 179.8. The incidence rate of accident in male was 86.5 which was about 2 times that in female. In male, the highest incidence rate was seen in 30-39 age group and in female, 60-69 age group. The highest incidence rate of accident was observed in spring(29.4%) and summer(29.4%), and the lowest in fall(17.7%). The highest incidence rate of accident was observed in Friday(24.5%) by day of week, and between 9 a.m. to 12 a.m. by time zone. The most frequent use of medical facilities was Primary Health Post(51.8%) and the next was clinic(38.8%). Mean duration of treatment was 9.8 days. The accident occured in the room and kitchen(23.5%), in the yard and barn(23.5%), on the road(22.4%). and in the rice field and dry field(20.0%). The causes of accident were motor vehicle accident(20.0%), piercing or cutting(20.0%), collision or fighting(12.9%), and poisoning(11.8%) in order of frequency. The most common type of injury was open wound which was 43.5%. The most common tool of accident was farm machine which was 23.5%. The most common injuried part of body was extremity(55.3%).

• Journal of The Korean Society of Grassland and Forage Science
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• v.30 no.4
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• pp.317-324
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• 2010

Recently, fallow paddy land located in the mid-mountain area (FPL) due to a decrease in rice consumption has increased in some regions of our country. So, grasses and forage crops available for years in once sowing should be introduced in FPL. This study was conducted to develop the technique for cultivation of grasses and forage crops using animal manure in FPL The field experiments were carried out from 2007 to 2009 on FPL at Kumsan, Chungbuk province in Korea. Cattle feedlot manure (CFM) was prepared by mixing feces and urine of cattle with rice straw in cattle feedlot for 6 months. The experimental plots were consisted of four treatments; tall fescue-based mixed pasture applied with chemical fertilizer (Control), mono-tall fescue pasture (MTFP), tall fescue-based mixed pasture (TFBMP), mono-Perennial ryegrass (MPR-FCM), mono-Italian ryegrass (MIR-FCM), mono-Red clover (MRC-FCM) and mono-Reed canarygrass (MRCG-FCM) applied with FCM. The field of tall fescue-based pasture had been sown with a grasses mixture containing 'Fawn' tall fescue, 'potomac' orchardgrass, 'Reveille' Perennial ryegrass, and 'kenblue' Kentuky bluegrass, 'Kenland' Red clover. Seeding rates were 16, 6, 4, 2 and $2\;ha^{-1}$, respectively. DM yields of forages and rates of grass coverage was higher in MTFP, TFBMP and MRCG-FCM as compated with control treatment. This result means that FPL has contained with favorable conditions for growing grass, because forage productivity is more than 15 tons per ha per year in fallow paddy land. In addition, the farmer can save the trouble of repeated plowing and sowing every year, due to the introduction of perennial grasses. The farmer must conduct the re-seeding and induce the improvement of management methods for the elevation of the persistence of red clover and perennial ryegrass, because both red clover and perennial ryegrass having high nutritive value and palatability was less persistent. Therefore, we suggest that FPL may be the good land for forage production utilizing FCM and FCM can be applied on FPL without any negative effects on DM production and the property of soil. FPL of Korea can be better utilized by applying FCM to the mono and/or mixed swards.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.2
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• pp.117-124
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• 2012

This study was conducted to estimate Hanwoo carrying capacity when whole crop barley or rye as winter forage crops was grown on different applying sources (chemical fertilizer, cattle or organic fertilizer) and mixed sowing combination with hairy vetch or forage pea during the period of 2008~2010. The experimental plots within whole crop barley or rye were consisted of 7 treatments, which were non-fertilizer, chemical fertilizer (P+K), chemical fertilizer (N+P+K), organic fertilizer, cattle slurry, cattle slurry with hairy vetch, and cattle slurry with forage pea. Each plot was triplicates and experimental treatments were allocated in the randomized complete block design. For whole crop barley, annual mean dry matter (DM) and total digestible nutrients (TDN) yields were the highest in N+P+K plots, but there were no significant differences among organic fertilizer, cattle slurry and mixed sowing with legumes. The TDN and RFV were the highest in mixed sowing plots of forage pea plus cattle slurry application. As 450 kg Hanwoo heifers were fed diets included 70% whole crop barley, organic fertilizer, cattle slurry application and mixed sowing with legumes plots is capable of raising average 2.5 to 2.9 heads/ha a year. For whole crop rye, annual DM, crude protein, and TDN yields of application groups and mixed sowing treatment with legumes showed 6.69~7.13, 0.46~0.51 and 3.95~4.18 ton/ha, respectively. In case of 450 kg Hanwoo heifers fed diets included 70% forage rye, it is estimated that cattle slurry application (mixed sowing with legumes) plots can rear average 3.1~3.3 heads/ha a year. It can be concluded that, on the basis of DM yield, not only mixed sowing with legumes by applying cattle slurry rather than single sowing of whole crop barley or whole crop rye enhanced production yield and feed values, but also it could be a substitute for imported grains as dietary protein sources in the case of feeding Hanwoo.

• Fire Science and Engineering
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• v.25 no.4
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• pp.8-21
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• 2011

This study surveyed historical records on outbreak and features of forest fires during Chosun Dynasty's 518 years in being and analyzed the Annals of the Chosun Dynasty; The Diaries of the Royal Secretariat, archives from Records of the Border Defense Council, The Compilation of Ministry Proposals, Posthumous Records of King Cholchong etc. Forest fires were most prevalent and extreme during King Hyunjong (14 cases) and King Sunjo (13 cases) due to strong wind, and the biggest-ever forest fire broke out in the fourth year of King Soonjo (1804) in the east coast of Korea in Kangwon province. The fire had resulted in 61 fatalities and 2,600 destroyed houses. Forest fire in the east coast of Korea, Kangwon province, in the $13^{th}$ year of King Hyeonjong (1672) is recorded to have caused the highest number of deaths, 65people. The most frequent cause of forest fires during Chosun Dynasty was unidentified (42 cases), followed by accidental fire (10 cases), arson or lightning (3 cases), fire during hunting (2 cases), play with fire by children, destruction of patty fields and dry fields by fire and house fire (1 case respectively). By region, 56 % of forest fires erupted in the east coast (39 cases) and this was followed by the west sea (9 cases), Seoul and central region (8 cases) and the southern part of Korea (7 cases). By season, spring was found to be most vulnerable to forest fire as it accounted for 73 % of the total amounting to 46 cases. Behind were summer (11 cases), winter (6 cases) and autumn (0 case). Specifically, most forest fire broke out on April and May, which is the same as today. Archives and literature indicate that the person who involved in forest fire by accidental as well as arson had to be punished by banishment, expulsion from government office and public hanging. Also, officials in charge of the region that suffered forest fire were subject to reprimand. In conclusion, risk and gravity of forest fires were evident during the Chosun Dynasty as specified in historical archives and share many similarities with today's forest fires in terms of the duration and regional patterns.

• Korean Journal of Organic Agriculture
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• v.21 no.2
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• pp.207-217
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• 2013

This study was conducted to estimate organic Hanwoo carrying capacity when whole crop wheat and triticale as winter forage crops were grown on different applying sources (no fertilizer, organic fertilizer or cattle slurry), and mixed sowing in combination with hairy vetch and forage pea at the level of 50% cattle slurry application during the period of 2009~2011. The experimental plots were consisted of 5 treatments. Each treatment was triplicates and allocated in the randomized complete block design. For whole crop wheat, annual mean dry matter (DM) yield was significantly (P<0.05) higher for fertilizer application treatments than for no fertilizer treatment, and crude protein (CP) yield was significantly (P<0.05) higher for forage pea and hairy vetch-mixed sowing treatments than for no fertilizer and organic ferilizer treatments. Mean CP, total digestible nutrients (TDN) and relative feed value (RFV) contents of legumes-mixed sowing treatments was significantly (P<0.05) higher than those of other treatments. As diets replaced with 70% whole crop wheat were provided for 450kg of Hanwoo heifers, legumes-mixed sowing treatments could raise more heifers than organic fertilizer and no fertilizer treatments. For triticale, annual mean DM, CP and TDN yields were significantly (P<0.05) higher for fertilizer application treatments than for no fertilizer treatment, and CP content of legumes-mixed sowing and cattle slurry application treatments was significantly (P<0.05) higher than that of other treatments. When 450kg of Hanwoo heifers were fed on diets replaced with 70% triticale, it was estimated that legumes-mixed sowing treatments at the level of 50% cattle slurry application could rear average 3.3~3.4 heads/ha/year, which was significantly (P<0.05) higher than no fertilizer treatment (2.5 heads/ha/year). It was indicated that DM yields of whole crop wheat and triticale were much more effective in cattle slurry application than organic fertilizer, and Legumes-mixed sowing at the level of 50% cattle slurry application rather than whole crop wheat or triticale alone increased yields per unit area and nutritional value such as CP content. In conclusion, it is conceived that whole crop wheat or triticale produced in the manner above can be used instead of grains imported as dietary protein sources in the organic Hanwoo feeding regimen.

• Journal of The Korean Society of Grassland and Forage Science
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• v.32 no.4
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• pp.411-418
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• 2012

This study was conducted to develop the technique for cultivation of forage crops using swine slurry in fallow paddy land located in the mid-mountain area (FPL). The field experiments were carried out from 2007 to 2009 on FPL at Kumsan, Chungbuk province in Korea. Swine slurry was prepared which decayed for 6 months. The experimental plots were consisted of seven treatments; tall fescue-based mixed pasture applied with chemical fertilizer (Control), mono-tall fescue pasture (MTF), tall fescue-based mixed pasture (TFBM), mono-Perennial ryegrass (MPR), mono-Italian ryegrass (MIR), mono-Red clover (MRC and mono), Reed canarygrass (MRCG) applied with swine slurry. The field of tall fescue-based pasture had been sown with a grasses mixture containing 'Fawn' tall fescue, 'potomac' orchardgrass, 'Reveille' Perennial ryegrass, and 'kenblue' Kentuky bluegrass, 'Kenland' Red clover. Seeding rates were 16, 6, 4, 2 and 2 (kg) per ha, respectively. DM yields of forages and rates of grass coverage were higher in MTF, TFBM and MRCG as compared with control treatment. This result means that FPL has contained with favorable conditions for growing grass, because forage productivity is more than 14.5 tons per ha per year in fallow paddy land. In addition, the farmer can save the trouble of repeated plowing and sowing every year, with the introduction of perennial grasses. The farmer must conduct the re-seeding and induce the improvement of management methods for the elevation of the persistence of red clover and perennial ryegrass, because both red clover and perennial ryegrass having high nutritive value and palatability was less persistent. Therefore, we suggest that FPL may be the good land for forage production utilizing swine slurry and swine slurry can be applied on FPL without any negative effects on DM production and the property of soil. FPL of Korea can be better utilized by applying swine slurry to the mono and/or mixed swards.

• Journal of The Korean Society of Grassland and Forage Science
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• v.38 no.1
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• pp.61-73
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• 2018

The objective of this study was to investigate the suitable method for rapid establishment of grassland according to forage species, mixed pastures and installation of mesh at 35 degree angle of cutting area in the middle region of Korea. In agronomic characteristics after wintering, vegetation coverage of Tall fescue(TF) was 74% in monoculture, which was the highest among 3 forage crops. Meanwhile average vegetation coverages of monoculture and mixed pasture were 67 and 92% in treated of mesh, which were 4 and 18% higher than untreated of mesh, respectively. In botanical composition, TF of monoculture and Orchardgrass(OG) and TF oriented mixed were indicated over 94% forage coverage. Meanwhile forage coverages Kentucky bluegrass(KBG) and Red top(RT) of monoculture and Perennial ryegrass(PRG) oriented mixture were 89, 81 and 92% in treated of mesh, which were 7, 6 and 5% higher than untreated of mesh, respectively. In forage productivity, dry matter yield(DMY) of TF(12,537kg/ha) and KBG(11,897kg/ha) of monoculture were significant(p<0.05) higher than RT(9,604kg/ha). Meanwhile DMY of OG(12,227kg/ha), TF(12,823kg/ha) and PRG(11,871kg/ha) oriented mixed were not significant difference(p>0.05). In forage quality of monoculture, in the first year, crude protein of KBG was 13.6%, which was the highest among 3 forage species. Also neutral detergent fiber(NDF) of TF was 56.5%, which was the lowest among 3 forage species. In mixed pasture, in the second year, NDF and acid detergent fiber of PRG oriented mixed were 56.5 and 34.3%, respectively, which was the lowest among 3 mixed pasture. In conclusion, forage species TF was more suitable on initial rootage and continuous forage coverage, OG and TF oriented mixed were more suitable on continuous forage coverage. Also the installation of mesh showed positive effects on initial rootage and maintain forage ratio.

• Journal of Wetlands Research
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• v.16 no.1
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• pp.61-72
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• 2014

To present a guideline on the construction and management of artificial wetlands for high biomass production, three emergent macrophytes (Phragmites australis, PA; Typha angustifolia, TA; and Zizania latifolia, ZL) were planted under two substrates conditions (general soil with and without moss peat) and two water levels (5 cm and 20 cm) and monitored for three years. ZL showed greater growth performance rather than the others not only at early growth phase in the first year [shoot height, 200 cm; above-ground dry weight (AGDW), 500 $g/m^2$] but also in the last year (ZL, 1,100 $g/m^2$; TA, 770 $g/m^2$; and PA, 450 $g/m^2$ of AGDW). ZL with rapid growth at the early growth phase was not affected by naturally introduced weeds, whereas slower and poorer growth of PA and TA at the early growth phase resulted in relatively higher introduction and establishment of natural weeds. In turn, such introduced weeds negatively contributed to the growth of PA and TA particularly under shallow water (5 cm) with the substrate condition including moss peat. We suggest a plant material with rapid and great growth at the early phase such as ZL for reducing possible negative influences by the natural weeds and wild animals for high biomass production in constructed wetlands. A pre-growing process in greenhouse prior to planting might be an useful option to raise the competitiveness of those species when planting PA and/or TA. In addition, we recommend that integrated weed management system with utilizing various options at the most appropriate timing must be applied for maintaining sustainable high biomass production at the artificial wetlands.