• Journal of The Korean Society of Grassland and Forage Science
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• v.43 no.1
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• pp.11-21
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• 2023

This study was conducted to estimate the damage of Whole Crop Corn (WCC; Zea Mays L.) according to abnormal climate using machine learning as the Representative Concentration Pathway (RCP) 4.5 and present the damage through mapping. The collected WCC data was 3,232. The climate data was collected from the Korea Meteorological Administration's meteorological data open portal. The machine learning model used DeepCrossing. The damage was calculated using climate data from the automated synoptic observing system (ASOS, 95 sites) by machine learning. The calculation of damage was the difference between the dry matter yield (DMY)_normal and DMY_abnormal. The normal climate was set as the 40-year of climate data according to the year of WCC data (1978-2017). The level of abnormal climate by temperature and precipitation was set as RCP 4.5 standard. The DMY_normal ranged from 13,845-19,347 kg/ha. The damage of WCC which was differed depending on the region and level of abnormal climate where abnormal temperature and precipitation occurred. The damage of abnormal temperature in 2050 and 2100 ranged from -263 to 360 and -1,023 to 92 kg/ha, respectively. The damage of abnormal precipitation in 2050 and 2100 was ranged from -17 to 2 and -12 to 2 kg/ha, respectively. The maximum damage was 360 kg/ha that the abnormal temperature in 2050. As the average monthly temperature increases, the DMY of WCC tends to increase. The damage calculated through the RCP 4.5 standard was presented as a mapping using QGIS. Although this study applied the scenario in which greenhouse gas reduction was carried out, additional research needs to be conducted applying an RCP scenario in which greenhouse gas reduction is not performed.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.4
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• pp.387-392
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• 2016

This study was conducted to ameliorate the productive performance of Hanwoo cow using hill pasture grazing system. Twenty seven animals aged 9 were designed to divide with 3 groups which were Control (restricted concentrate and hay for 5 months), T1 (restricted concentrate and pasture grazing ad libitum for 5 months) and T2 (restricted concentrate, 30 g/head of mineral nutrients and pasture grazing ad libitum for 5 months). Average daily gains increased higher in the order of T2, Control and T1. The conception rate of Control, T1 and T2 after artificial insemination during post-grazing period were 88.9%, 100%, 100%, respectively. In conclusion, the results indicated that hill pasture grazing system might enhance not only the productive performance of Hanwoo cow but also profit for conventional feeding system.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.1
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• pp.1-10
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• 1999

To find out the way to be able to prolong the grazing years of mixed pasture under Cheju summer-hot weather, an experiment designed with split plot (main plot : 3 cutting-plant height such as 15cm, 30cm and 45cm and sub plot : 4 white clover varieties such as Regal, Tahora, Brown and SRVR) was carried out at Cheju Agricultural Experiment Station during the period from Sept. 1994 to Oct. 1996 Dry matter yield in 15cm plant height in cutting dates has shown significantly lower increase than those in 30 and 45cm(P<0.05). There was highiy significant increase in dry matter yield of Brown plot when compared with other varieties of white clover in 2nd year(P<0.01). There was no difference on botanical composition of mixed sward as affected by plant height in cuttings dates in 2nd year. The percentage of white clover tends to lower in white clover varieties Brown and SRVR when compared with Regal and Tahora. The rate of weed was not affected by plant height in cutting dates and white clover variety in mixed pasture at last cutting time of 2nd year. In 15cm plant height, concentration of ADE and NDF was the lowest one while P contents was the highest one(P<0.01). Potassium contents was the lowest one in 30cm plant cutting height(P<0.05), and nitrogen showed statistically interaction between plant cutting height and white clover variety(P<0.01). White clover variety was no effective on concentration of constituents in mixed pastures. In conclusion, white clover variety SRVR harvested at 15cm plant height is effective on nutrient value of pasture and balance of grass and white clover in botanical composition.

• Journal of The Korean Society of Grassland and Forage Science
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• v.12 no.1
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• pp.59-66
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• 1992

An experiment was conducted to determine the effects of seeding rates and nitrogen fertilization levels on the agronomic characteristics, nutritive value and forage yield of spring oat(Avena sativa L.). This experiment was undertaken over a period of 2 months from September to November, 1987. The results obtained are summarized as follows : Increased seeding rates of 120, 160 and 200kg/ha decreased emergence rates by 93.4, 71.4 and 70.6 %, respectively(P<0.05). Tillering was decreased by higher seeding rates(P<0.05) and that of 120kg/ha of seeding rate with 200kg/ha of nitrogen fertilization level was highest by 3.3. Among three seeding rates, tillering of 200 kg/ha of nitrogen fertilization level was lowest by 2.1. Leaf width was influenced by seeding rates. When seeding rate was increased, narrow leaf width (P

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.4
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• pp.287-296
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• 2002

A field trial was conducted from May to November 2000 at four regions of Jeju province(Jeju, Seogwipo, Susan Seongsan and Keumak Hallim) to estimate adaptation, dry matter yield and nutrient value of kenafs(Everglades 41 and China Choung-pi 3) and a sorghum-sudangrass hybrid(Pioneer 947). Total dry matter(DM) yields of sorghum-sudangrass hybrid Pioneer 947, kenaf Everglades 41 and kenaf China Chong-pi 3 were 7,313, 4,653 and 5,238 kg/ha(P<0.05), respectively, kenaf China Chong-pi 3 being the highest. The region specific dry matter(DM) yields of Jeju, Seogwipo, Seongsan and Hallim area were 5,040, 5,663, 7,283 and 4,950kg/ha, respectively, showing that Seogwipo was the highest. Average DM yields of two kenaf varieties were 4,946, and 3,246 kg/ha for 1st time-cutting and 2nd time-cutting, respectively. The average dry matter(DM) yield of kenaf was significantly higher in the 1st time-cutting than the 2nd time. No significant difference in neutral detergent fiber(NDF) and acid detergent fiber(ADF) contents was found among three varieties. The average crude protein(CP) content of kenaf was higher than that of sorghum-sudangrass hybrid(P<0.05) and was higher in 2nd time-cutting than in 1st time-cutting(P<0.05). There were no significant difference in the heavy metal content of soil either between the sorghum hybrid and kenafs or between two kenaf varieties. In conclusion, the average dry matter(DM) yield of kenaf was lower than that of sorghum hybrid, Contrarily the crude protein(CP) content of kenafs was higher than that of the sorghum hybrid. The average dry matter(DM) yield of kenaf showed higher in 1st time-cutting than 2nd time-cutting, while the crude protein(CP) content of kenafs decreased with time.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.4
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• pp.286-293
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• 1993

This study was carried out to determine the effects of the fertilization levels and oversowing treatment on liveweight gain of glazing cattle, changs of botanical composition, and dry matter(DM) yield in tall fescue dominant mixed pasture during the grazing period. The treatments were T$_1$(low fertilizing; 120-100-100 kg/ha), T$_2$(medium fertilizing; 280-200-200 kg/ha) and T$_3$(medium fertilizing+oversowing). The botanical composition of tail festuce was increased in T$_1$ and that of tall fescue, orchardgrass and pernnial ryegrass in T$_3$ was 30.5%, 23.8% and 24.1%, respectively. The total forage DM yield was the highest in T$_3$, and the average stocking rate (animal unit; AU) per day during the grazing period in T$_1$, T$_2$ and T$_3$ was 2.4 AU. 3.0 Au and 3.3 AU, respectively. The total grazing days (animal unit day; AUD) in T$_3$(664 AUD) was higher than that of T$_1$, and T$_2$. There is no significant difference in average daily liveweight gain per head among the treatments but daily liveweight gain per ha in T$_3$ was higher than that of T$_1$, and T$_2$. The total liveweight gain per ha during the grazing period in T$_1$, T$_2$ and T$_3$ was 601kg. 762kg and 877kg, respectively. The herbage consumption per day per 100kg LW was similer among the treatments but crude protein, P, K and Ca contents in herbage were increased with medium fertilization levels(T$_2$) and with oversowing(T$_3$).

• Journal of The Korean Society of Grassland and Forage Science
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• v.29 no.3
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• pp.211-216
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• 2009

Approximately 43 million tons of livestock manure (LM) are produced each year on Korean farms. LM can be utilized as a valuable resource and/or it can contaminate water by runoff and leaching through the soil, when LM has been thoughtlessly applied to the land and directly discharged into the water. This experiment was carried out to investigate the effect of no-till system and LM application on dry matter (DM) yield of silage corn and $NO_3$-N concentration in leaching water of lysimeter installed in the experimental field. The treatments were replicated three times in split plot design. Main plots consisted of tillage systems, such as conventional tillage (CT) and no-tillage (NT). Sub plots consisted of the type of LM, such as chemical fertilizer (CF), composted cattle manure (CCM) and composted swine manure (CSM). The control plots were fertilized as commercial chemical fertilizer. DM yields of corn increased significantly in order to CF > CCM > CSM (p<0.05). DM yield of corn in CT increased as comparing with that of corn in NT. Plant height, ear height and stem diameter also increased in order to CF > CCM > CSM. In addition, the root weight in CT was increased as comparing with that of corn in NT. However, there was no interaction effects of between type of LM and tillage system. $NO_3$-N concentration in leaching water of LM application was less than 10 ppm, but $NO_3$-N concentration in CF exceeded 10 ppm which is safety level of drinking water during summer time (rainfall season).

• Journal of The Korean Society of Grassland and Forage Science
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• v.35 no.2
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• pp.87-92
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• 2015

This experiment was conducted to evaluate the effect of seeding methods and application levels of nitrogen fertilizer on the yield and forage quality of whole crop rice (WCR). The WCR variety "Namil" was directly seeded on April 25 and transplanted on May 25. Five levels of nitrogen fertilizer were applied (90, 110, 140, 170 and 200 kg/ha). There were no significant differences (p<0.05) of the emergence date, heading date and disease resistance based on the nitrogen fertilizer rates; however, the WCR became dark at higher nitrogen fertilizer rates. The plant height increased at higher nitrogen fertilizer rates and the tiller number showed the same trend. In contrast to a direct seeding method, transplanting increased the tiller number. The dry matter (DM) content did not show a certain tendency based on nitrogen fertilizer rates, while the fresh and dry matter yields increased with incremental changes of the nitrogen fertilizer rates (p<0.01), and the transplant method increased the yield size. In yield analysis, the plot direct-seeded with 140 kg N/ha and the transplanting with 170kg N/ha showed the highest yields. The crude protein (CP) content increased with higher nitrogen fertilizer rate, but there was no significant differences between transplant and direct-seeding methods. The content of ADF (acid detergent fiber) and NDF (neutral detergent fiber) increased with higher nitrogen fertilizer rate, but total digestible nutrient (TDN) content decreased with increased nitrogen levels. Although high nitrogen applications increased the fresh and DM yields, the 140 kg/ha nitrogen fertilizer level is recommended as the proper nitrogen fertilizer level, considering both yield and the environments.

• Journal of Food Hygiene and Safety
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• v.22 no.4
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• pp.273-278
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• 2007

Recently, the demand for the powdered products to process raw grains and vegetables has been expanded, and the growth possibility of their fields(markets) in the future will be highly valued with the westernization of living environment and the change of the dietary life. We have bought and analyzed the 111 products of raw grains and vegetables from the large-sized marts, markets and internet orders from March to October 2006. The rate of moisture content was $1.7{\sim}12.5%$. We also found out that the foods over 10% moisture content was 8 of those samples we bought or collected. Their ash rates were averagely $0.3{\sim}8.6%$. The number of those foods that the alien substances were detected was 2. The tar pigments, artificial sweeteners and sulfur dioxides of components that contained food additives were not detected. Each detection range of Cadmium, Lead and Arsenic of the injurious heavy metals was non-detectable $(nd){\sim}0.55,\;nd{\sim}4.52,\;nd{\sim}0.10mg/kg$, while the average detection content were 0.08, 0.48, 0.01 mg/kg. By investigating the contamination degree of the microflora, we discovered that the number of the aerobic plate count, B. cereus over 1,000 cfu/g and C. perfringens over 100 cfu/g was 36 (32.4%), 9 (8.1%) and zero, and that the whole sanitation condition of the products of powdered raw grains and vegetables circulated in the market was not so good.

• Journal of The Korean Society of Grassland and Forage Science
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• v.19 no.2
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• pp.115-120
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• 1999

This experiment was carried out to investigate the effects of additives on the quality of alfalfa(Medicago sativa L.) silage at the forage experimental field, National Livestock Research Institute, RDA, Suwon in 1996. The experiment was arranged in a randomized block design with three replications. The treatments consisted of different additives(control, formic acid, molasses, inoculant A and inoculant B). Crude protein(CP) and Nitrogen free extract(NFE) content of alfalfa silage with additives were higher compared with those obtained control, but Crude ash(CA) and Crude fiber(CF) content of control(11.5 and 39.6%) were higher than those of additive treated plots. ADF and NDF contents of control silage were the highest as 36.2 and 48.6%, respectively, and increased by 4% compared with those obtained before ensiling. The acidity(pH) of control was the highest(5.45), but the lowest in inoculant A(4.32). Inoculant teratment significantly reduced acidity of silage compared with control. DM content of control silage was the lowest but DM loss of control silage was higher than that of additive treated silage. Ammonia-N content was the highest at formic acid treatment and level of Lactobacillus was decreased at control and formic acid treated silage. Total organic acid and lactic acid content of inoculant A and inoculant B were higher than those of other treated plots. The results of this study indicate that the treatment of LAB(Lactic acid bacteria) could be recommended as producing high quality of alfalfa silage.