• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.3
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• pp.145-150
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• 1986

The experiments were conducted to study the influence of growth location and cutting microelements macro-and on managements in temperate grasses in Korea and West Germany from 1975 to 1979. The field trials were designed as split plot with three grass species of Dactylis glomerata L., Lolium perenne L. and Festuca pratensis Huds under three cutting regimes at grazing stage, silage stage and hay stage. The results obtained are summarized as follows: 1. Concentrations of macro-and microelements in temperate grasses showed a different response to growth location and growing season. P concentration in the plants was decreased under hot stress in summer, whereas Mg and Na tended to be increased. The seasonal changes in K and Zn were not significant. 2. Morphological growth stage was to be found as an important factors influenced to mineral components. P and K contents in temperate grasses tended to be decreased as morphological development especially under high temperature in Suweon and Cheju. Ca and Mg were less affected by morphological stage and cutting managements. 3. Mean value of Ca/P ratio in the plants were 1.58, 1.33 and 1.21 for meadow fescue, perennial ryegrass and orchardgrass, respectively. Ca/P ratio in grasses tended to be increased as morphological development. 4. Zn deficiency in the plants occured in all grass species and experimental sites. Mean Zn concentration of the plant were 34.2%, 31.2% and 37.8% for Suweon, Cheju and Taekwalyong, respectivelly. Na deficiency occured in orchardgrass and meadow fescue, especially in taekwalyong. Cool temperature resulted in a decrease of Na absorption and accumulation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.3
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• pp.3-12
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• 1992

Forage grasses and legumes ar$\varepsilon$ the mam component of livestock diets in Canada. There are over 30 million ha of grassland in Canada and there is a large, undeveloped land base in fringe areas suitable for forage production. The short growing s season limits the grassland farming to the southern p parts of Canada. The win!er season is long and in most parts of Canada cold temperatures, fr$\varepsilon$ezmg, and thawing, and diseases exert sever$\varepsilon$ stress on overwintering forage plants. The development of persistent cultivars is essential for sustained production particularly in the fringe areas with short growmg s$\varepsilon$ason. The seasonality of dry matter production is a result of high growth rates in early summ$\varepsilon$r and low dry matter accumulation in late summer and fall. Innovative management practIces a and cultivars with improved regrowth capacity are n necessary to overcome such skewed production pattern and to extend effiectlVe grazmg season l Improved pasture production is an important part of reducing costs in livestock operations and remaining competitive. It is suggested that applying available technology would increase pasture productivity and reduce d$\varepsilon$pendence on stored feeds thus improving profitability of small producers in particeular. Reducing nutrient losses during harv$\varepsilon$stmg, s storage, and feeding is essential for improved production efficiency during confinement. The devclopment of low cost and labor saving methods of ensiling is critical for improved efficiency and profitability of forage based enterprises Livestock industries must respond to consumer preferences for low fat and cholesterol foods. Research and development of entire production systems is emphasized for dev$\varepsilon$loping viabl$\varepsilon$ enterprises. It is increasingly difficult to secure resources for r$\varepsilon$search, education, and extension, and alliane$\varepsilon$s and cooperation must expand among organizations with interests in forage based livestock systems.

• Korean Journal of Breeding Science
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• v.41 no.4
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• pp.649-653
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• 2009

"Cheongan" is a new japonica rice variety developed from a cross between SR15225-B-22-1-2-1 and Iksan431 in summer season, 1997 by National Institute of Crop Science, RDA. The line SR15225-B-22-1-2-1 has good canopy architecture and multi-disease and insect resistance, and Iksan431 has translucent milled rice and good eating-quality. Heading date of Cheongan is August 13 in central lowland and mid-mountainous areas. "Cheongan" having culm length of 84 cm shows relatively semi-erect pubescent leaf blade and rigid culm, tolerance to lodging with and good canopy architecture. This variety has 14 tillers per hill and 126 spikelets per panicle. It shows tolerance to heading delay and spikelet sterility comparable to Hwaseongbyeo when exposed to cold stress. Leaf senescence of Cheongan progresses slowly during the ripening stage and the viviparous germination ratio was 59 %, similar to that of Hwaseongbyo. "Cheongan" shows moderately resistance to blast disease, but susceptible to stripe virus and brown planthopper. The milled rice of "Cheongan" exhibits translucent, clear non-glutinous endosperm and medium short grain. It shows similar amylose content of 18.7%, gelatinization temperature, and similar palatability of cooked rice compared to Hwaseongbyeo. The milled rice yield of this cultivar is about 5.54 MT/ha at ordinary season culture in local adaptability test for three years. Especially, "Cheongan" has better milling properties of higher 98.4% and 73.9% in the percentage of head rice in milled rice and milling recovery of head rice, respectively, than those of Hwaseongbyeo. "Cheongan" could be adaptable to the central and mid-southern plain area, and mid-western coastal area of Korea.

• Journal of The Korean Society of Grassland and Forage Science
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• v.41 no.4
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• pp.223-233
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• 2021

The objective of this study was to investigate the effect of gypsum on the dry matter yield and the chemical composition of alfalfa in reclaimed tideland with soil dressing. The experimental site was Sukmoon reclaimed tideland. The tideland was reclaimed approximately 17 to 33 years ago and the 70 cm of soil was top-dressed. The soil that covers the reclaimed tideland brought from the island did not treat di-salinized. Treatments were consisted of three groups; control group where no gypsum (G0) was applied and two experimental groups where 2 ton/ha (G2) and 4 ton/ha (G4) of gypsum were applied, respectively. The first harvest was conducted when the alfalfa reached early flowering (open the flower 10%), and after that subsequent harvest was conducted at approximately 35 days intervals. The dry matter yield of the alfalfa showed that G2 was significantly higher in the first year than G0 and G4, and G2 tended to be higher in the second year than G0 and G4, although there were no significant differences between treatments. The reason for the high dry matter yield in G2 was that the soil pH and EC of the soil were at marginal and ideal levels and the coverage and alfalfa botanical composition were also high. In both years, there were no differences in the crude protein, neutral detergent fiber and acid detergent fiber contents and relative feed value between gypsum treatments. Meanwhile, the results in the first and second years showed that the alfalfa dry matter yield were negatively affected by droughts stress in spring and concentrated precipitation in summer. Therefore, this study suggests gypsum treatment in reclaimed tidal land could increase the dry matter yield of alfalfa, and 2 ton/ha of gypsum was the optimum rate.

• Ecology and Resilient Infrastructure
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• v.8 no.2
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• pp.79-87
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• 2021

Because active interactions occur among vegetation, hydrology, and geomorphology in riparian systems, any changes in one of these factors can significantly affect the other two. In this study, we evaluated these interactions at four sites (two in Gajeong and two in Hahan) along the Seomjin-gang River that was substantially devastated by an extreme flood in 2020. We examined the relationship between the riparian vegetation and the hydraulic characteristics of the flood using remote sensing, hydraulic modeling, and field surveys combined. The evaluation results showed that the floods caused a record-breaking rise of up to 43.1 m above sea level at the Yeseong-bridge stage gauge station (zero elevation 27.4 m) located between the Gajeong and Hahan sites, with the shear stress being four times higher in Hahan than in Gajeong. Additionally, the water level during the flood was estimated to be a maximum of 1 m higher depending on the location in the presence of riparian plants. Furthermore, both sites underwent extensive biological damage due to the flood, with 78-80% loss in vegetation, with preferential damage observed in large willow species, compared to Quercus acutissima. The above findings imply that all plant species exhibit different vulnerabilities towards extreme floods and do not induce similar behavior towards events causing a disturbance. In conclusion, we developed strategies for effectively managing riparian trees by minimizing flood hazards that could inevitably cause damage.