• Journal of The Korean Society of Grassland and Forage Science
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• v.14 no.1
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• pp.50-56
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• 1994

This study was investigated for the purposes of securing forage resource using idled rice paddy recently increased in accordance to a current trend of farm products' liberalization and also of presevation of environment by using cattle sluny as liquid manure, which is seriously increasing these days. In this study, mean annual dry matter yield and its seasonal variation with reed canarygrass, and a optimum rate of cattle sluny application were investigated. The results are as follows: 1. According to the conditions of cutting frequencies(3, 4 and 5 cutting per year), mean annual dry matter yield was recorded from 8.9 tons to 10.9 tons per hectare and was the highest at 3 cutting frequency. 2. The use of cattle sluny with the levels of between 300 and 360 kg N per hectare showed a significantly higher mean annual dry matter yield than that of the control (non-fertilization). 3. The treatments with 3 and 4 cutting frequencies(90 kg Nhdyear, 120 kg Nhdyear) recorded higher dry matter yields than the control of the former level by 1.23 tons and 2.34 tons respectively and in the treatment of 5 cutting frequency, the second level with cattle sluny of 300 kg Nhdyear showed an increased dry matter yield of 2.11 tons compared to the former level(l50 kg Nhdyear). With regards to nitrogen efficiency, one kg of nitrogen is applied to 13.7, 19.4 and 14.1 kg of dry matter yields in the conditions of 3, 4 and 5 cutting frequencies respectively. 4. In view of seasonal variance of annual dry matter yield, the second cut in 3 cutting frequency, the third cut in 4 cutting frequency and the third in 5 cutting frequency showed the highest ratio as 42, 37 and 32% respectively compared to the total. 5. Under the conditions of this study, the 'Input-Output curve' from 5 cutting frequency was the closest to sigmaformed process(i=0.9993) of various cutting frequencies, and the maximum marginal yield in the treatment was obtained at the level of 250 kg Nha with cattle sluny. The economic level of cattle sluny was between 371.0 and 402.2 kg N and the highest dry matter yield was obtained at 489.3 kg Mdyear in the same treatment

• Journal of Environmental Science International
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• v.9 no.2
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• pp.137-144
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• 2000

The observations on the seasonal fluctuation and distributional characteristic of organic matters on surface sediments and its origin were carried out at the 25 stations in Keogeum-sudo, southern coast of Korean Peninsula from February to October in 1993. I made an analysis on the environmental factors for surface sediments such as temperature, ignition loss, chemical oxygen demand, pheopigment, total sulphide, water content, mud content in grain size, COD/IL ratio and COD/sulphide ratio. The results are as follows ; 1) The range of temperature on the surface sediments was between 6.2${\circ}C$ and 24.6${\circ}C$. The highest mean temperatuer of mud was 24.0${\circ}C$ in summer, the lowest 6.6${\circ}C$ in winter. 2) Ignition loss(IL) fluctuated between 1.2% in winter and 16.8% in spring, that is to say, the seasons of increasing in temperature were very high ignition loss. 3) Chemical oxygen demand(COD) showed the highest mean value of 20.52 mg/g dry in summer within the range of 15/46~32.78 mg/g dry, while showed the lowest of 5.79 mg/g dry in winter within the range of 7.4~17.39 mg/g dry. 4) Pheopigment concentrations showed the highest mean value of 4.85 $\mu\textrm{g}$/g dry in autumn within the range of 0.84~9.21 $\mu\textrm{g}$/g dry, while it did the lowest mean value of 1.97 $\mu\textrm{g}$/g dry in summer within the range of 0.23~4.83 $\mu\textrm{g}$/g dry. 5) Total sulphide (H2S) fluctuated between no detect(ND) in spring, and 2.43 mg/g dry in sutumn. The highest mean value was 0.68 mg/g dry in sutumn, the lowest was 0.16 mg/g dry in spring. 6) Water content(WC) and mud content in grain size showed the mean value of 43.2% within the range of 26.5~59.7% and 91.0% within the range of 57.8~99.2%, respectively. 7) By the analytical results on the source of organic matter, it had been dumped from the seaweed farms in Keogeum-sudo coastal waters.

• Journal of Plant Biology
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• v.14 no.4
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• pp.19-26
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• 1971

The sample stand of Pinus rigida plantation was chosen from those at the Choongnam Forest Experiment Station, Choongnam. The diameter at breast height (D) and the height of tree (H) of each tree in the sample plot of 200$m^2$ were measured yearly a from 1967 through 1969. The stand was 12.7-13.4cm in mean diameter and had a stand density of 2,150 trees per ha. The trunk, branches and leaves of each sample tree were separately weighed according to the stratified clip technique. The allometric relation between D2H and dry weight of trunk (Ws), branches (Wb) and leaves (Wl) were approximated by $$W_s=0.05917 (D^2H)^{0.837}$$ $$W_0=0.00655 (D^2H)^{0.989 }$$ $$W_l=0.04466(D^2H)^{0.690}$$ From the above, the standing crops in the sample stand was estimated to be as much as 76.7, 81.7 and 88.2 tons of dry matter, above ground, per ha in 1967, 1968 and 1969, respectively. Annual net production, as the sum of the biomass newly produced during one year, was estimated at 4.97-5.47 tons per ha per year. The respiratory and the photosynthetic rate deduced from theoretical calculations were 0.045 and 0.74kg of dry matter per kg per year. Tentative estimate of annual respiratory loss was made and annual gross production was roughly estimated at 4.4-4.7 and 10.7-12.9 tons of dry matter per ha per year. The ratio of respiratory loss to gross production was approximately 36-41:1.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.5
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• pp.658-664
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• 2002

This study was conducted to determine a proper feeding regime for lactating Holstein cows during the warm season in Taiwan. In Feeding Trial, 21 lactating Holstein cows were randomly allotted into three feeding regimes in a Completely Randomized Design. The feeding regimes were roughage fed ad libitum along with concentrate fed either twice daily (2C) or four times daily (4C), and total mixed ration (TMR) for 8 weeks. No significant differences among the three feeding regimes were found in body weight changes, and intakes in terms of dry matter, crude protein and net energy. For milk yield and 4% FCM yield, 4C were higher than the other two feeding regimes (p<0.05). No significant differences were found in milk compositions or differences noted in the yields of the respective milk components. TMR was worse than 2C and 4C (p<0.05) in milk production efficiencies in terms of dry matter intake per kg milk yield, crude protein intake per kg milk protein yield, as well as dry matter intake, net energy intake and crude protein intake per kg 4% FCM yield. Three ruminally fistulated Holstein dry cows were randomly assigned into the same three feeding regimes in a 3${\times}$3 Latin Square Design. No significant differences were found among the feeding regimes in ruminal pH, ammonia nitrogen, total VFA concentration, molar percentages of VFA, and acetic acid: propionic acid ratio (C$_2$/C$_3$). Taken all together, roughage fed ad libitum and concentrate fed four times daily was the better feeding regime for lactating cows during the warm season in Taiwan.

• Journal of The Korean Society of Grassland and Forage Science
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• v.42 no.3
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• pp.146-154
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• 2022

This experiment was conducted to evaluate the growth characteristics and productivity of silage corn varieties developed in Korea. Corn cultivation was carried out using the experimental field in the Pyeongchang campus of Seoul National University (550 m above sea level). There have 10 domestic cultivars (Gwangpyeongok, Dacheongok, Yanganok, Jangdaok, Cheongdaok, Daanok, Sinhwangok, Sinhwangok II, Pyeonggangok, and Hwangdaok) with one imported cultivar (P1543) which tested as a control, and randomized block design with three replications. Among the 100-grains weight of the seeds, Dacheongok was the heaviest, and the germination rate for each variety was 74.6% on average, while that of Daanok and Sinhwangok were over 90%. Sinhwangok was the fastest in tasseling and silking date. The number of days required to be silking date was as slow as 85 days in Dacheongok, Cheongdaok and Pyeonggangok, and as fast as 80 days or less in Sinhwangok, Sinhwangok II and Hwangdaok. The plant height of P1543 was the highest as 344cm, and Hwangdaok and Daanok were short. In terms of the ratio of ears, Daanok had the highest rate of 60.18%, and Jangdaok and Dacheongok had the lowest. There was no significant difference in dry matter content in stover, but P1543 was generally higher in ear and total dry matter content. The dry matter yield was highest in P1543, and the yield of TDN was significantly higher in P1543 and Yanganok. There was a significant difference in the crude protein content of ears and the dry digestibility of stems (p<0.05), while there was no significant difference in the content of each part or element. Combining the above results, Yanganok was the highest in terms of yield, and Dacheongok, Sinhwangok and Pyeonggangok were also recommended for domestically grown corn varieties in the mountainous regions of Gangwon-do.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.45 no.6
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• pp.356-360
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• 2000

With isogenic waxy and non-waxy rice cultivars, growth responce as affected by leaf-removal treatment were examined in various fertilizer application. Vertical dry matter of culm was significantly decreased from ground upto 10cm. Culm dry matter of waxy rice was more steadily decreased than that of non-waxy rice. Starch content of culm in non-waxy rice was higher than waxy rice, and that in waxy and non-waxy rice were the lowest in three leaf-removal but no difference in single leaf-removal. Flag leaf in waxy rice and 2 nd leaf in non-waxy rice were dominantly affected yield by leaf-removal. The 1000-grain weight and rippend grain ratio of non-waxy rice were more higher than waxy rice and that in waxy and non-waxy rice were the lowest value in three leaf-removal but no difference in single leaf-removal treatments.

• Korean Journal of Environmental Agriculture
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• v.14 no.1
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• pp.1-6
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• 1995

This experiment was carried out to clarify the evapotranspiration and water use efficiency in rice plant canopy. Two rice cultivars, Daechungbyo(japonica type) and Samgangbyo(Tongil) were planted on the field of Suwon Weather Forecast Station in 1989. Evapotranspiration, dry matter production and leaf area of rice plant were measured to investigate the water use efficiency. There was significant correlation between cumulative evapotranspiration and dry matter production of aboveground. The parameter of linear regression was 4.13. The ratio of cumulative top dry matter production per cumulative evapotranspiration was increased until $5.5{\sim}5.9$ leaf area index. The de Wit's "m" value revealed maximum record at heading-flowering stage. At the harvest, the values were ranged from 175.5 to 191.7. The parameter of cumulative solar radiation to dry matter production was $1.011{\sim}1.248$. The evapotranspiration ratio(g.water/g.DW) of Samgangbyo(278) was higher than that of Daechungbyo (299.9). The efficiency of evapotranspiration(g.DW/g. water) was 1.58 in Daechungbyo and 1.98 in Samgangbyo.

• Journal of The Korean Society of Grassland and Forage Science
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• v.6 no.1
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• pp.24-30
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• 1986

This experiment was carried out in order to study the effect of fertilizer application and seasonal changes on the productivity of the native reed (Phragmites communis Trinius) on the reclaimed tidal flate in Chonnam province. The samples of reed were taken at about 30-days interval from May to October, 1982 and evaluated plant height, blade & sheath-stem ratio, grass yield, the feed compositions and in vitro dry matter digestibility (IVD). The results are summarized as follows: 1. Plant height, grass yield, crude protein content and in vitro dry matter digestibility of the reed were significantly increased by fertilizer application, and ADF content was significantly decreased. 2. According to the significance test of coefficience, there was a significant negative correlation (P<0.05) between in vitro dry matter digestibility and plant height, grass yield, and the content of crude fiber and ADF, but a positive correlation (P<0.05) between in vitro dry matter digestibility and blade & sheath-stem ratio, and the content of crude protein and crude fat.

• Journal of The Korean Society of Grassland and Forage Science
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• v.13 no.4
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• pp.294-299
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• 1993

This expeiment was conducted to evaluate the effect of the different planting and harvest date on dry matter yield and feed value of forage oat (Avena sativa L.). Seeds were planted on September 1 (first), September 11 (second) and September 21 (third planting date) by hand between rows 30cm and harvest were achieved on November 7 (first) and November 19 (second harvest date) 1992. 1. The plant height was influenced by planting and harvest date. the first planting date showed the tallest plant height. 2. Dry matter (DM) content decreased with delaying planting date from first to third planting date, DM varied from 15.1 to 13.5% and increased with delaying harvest date from first to second harvest date at the same planting date. 3. Leaf weight ratio increased delaying planting date from first to third planting date, varied from 52 to 77%. 4. The content of crude protein increased with delaying planting date from first to third planting date, varied from 14.3 to 25.4% NDF and ADF contents were influenced by planting date and harvest date, it was decreased with delaying planting date. 5. The dry matter yields per ha decreased with delaying planting date: it was 6, 705, 5, 520, and 2, 315 kg at first, second and third planting date, respectively. Significant difference has been obtained among planting date(P<.01). The dry matter yields increased with delaying harvest: it was 4, 027 kg at first and 5, 667 kg at second harvest(P<.01). 6. According to the results obtained from this study. it is suggested that planting date on September 1 and harvest date on November 19 would be recomendable for fall oat forage production.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.12
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• pp.1719-1724
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• 2016

The objective of this study was to determine the effects of physically effective neutral detergent fiber (peNDF) content in total mixed ration (TMR) on dry matter intake, digestibility, and chewing activity in fattening Hanwoo (Bos taurus coreanae) heifers. The experiment was designed as a replicated $3{\times}3$ Latin square using 12 heifers. Fattening heifers were offered one of three diets [high (T1), medium (T2), and low (T3) peNDF] obtained by different mixing times (3, 10, and 25 min) for the same TMR feed. The peNDF content of TMR was determined by multiplying the proportion of dry matter retained by a 1.18 mm-screen in a Penn State Particle Separator by the dietary NDF content. The $peNDF_{1.18}$ content was 30.36%, 29.20%, and 27.50% for the T1, T2, and T3 diets, respectively (p<0.05). Dry matter intake was not affected by peNDF content in TMR. Total weight gain in T1 group was significantly higher (p<0.05) than in T2 and T3 groups. However, weight gain did not differ between T2 and T3 groups. The feed conversion ratio decreased with an increase in the peNDF content (T1: 12.18, T2: 14.17, and T3: 14.01 g/g). An increase in the peNDF content of TMR was associated with a linear increase in the digestibility of dry matter, crude protein, crude fiber, neutral detergent fiber, and acid detergent fiber (p<0.05). Also, an increase in peNDF content of the TMR resulted in a linear increase in the number of chews in eating and ruminating (p<0.05), and consequently in the number of total chews (p<0.05). These results indicate that peNDF content affects digestibility and chewing activity. Consequently, the peNDF content of TMR should be considered for improving feed efficiency, digestibility, body weight gain, and performance in fattening heifers.