山地傾斜度 및 3 要素 施用水準이 草地土壤 및 牧草中 無機養分의 相互均衡과 Grass Tetany 危險性에 미치는 影響

鄭連圭(Yeun-Kyu Jung),李鍾烈(Jong-Yeol Lee) 한국토양비료학회 1986 한국토양비료학회지 Vol.19 No.3

석회 및 3 요소 시용수준이 겉뿌림 산지초지에 미치는 영향 3 . 목초의 무기성분함량 및 3 요소 이용율의 변화

정연규,이종열,심재성 ( Yeun Kyu Jung,Jong Yeal Lee,Jai Sung Shim ) 한국축산학회 1982 한국축산학회지 Vol.24 No.6

This field experiment was undertaken to assess the effects of two rates of Ca(OH)₂ (0, 250 ㎏/l0a) and five rates of N-P₂O_5-K₂O (0-0-0, 0-10-10, 6-15-15, 12-20-20, 24-25-20 ㎏/l0a) on the grassland establishment, forage yield and quality, botanical composition, and persistence of different forage species in a mixed grass/ clover sward established by oversowing method on new reclaimed steep mountain. This third part was concerned with the concentrations and uptake of mineral nutrients, and percentage recovery of NPK. The results obtained were summarized as follows; 1. Liming increased concentrations of N, Ca, Mg and Na in mixed forages, but effect of liming on concentrations of K and P was inconsistent. By increasing the NPK rate, concentrations of N, P, K, Rnd Ns in mixed forages were increased, whereas Ca and Mg concentrations tended to be reduced. 2. Overall values of Mg concentrations in mixed forages were below 0.15%. That value is considerably below 0.15%. That value is considerably below the critical level for forage growth and likelihood of grass tetany ($lt;0.2%). Amounts of individual and total mineral uptake, and total concentration of minerals were increased by both liming and increasing the NPK rate. 3. Liming increased markedly the percent recoveries of N,P and K, Percent recovery of N was reduced by increasing the N rate, whereas those of P and K were inconsistently affected by their application rates. The percent recoveries of N, P and K by mixed forages were highest in the order; K$gt;N$gt;P. 4. Forage quality was greatly influenced by both liming and applications of NPK. Concentrations of N, P, K, Ca, Mg and Na were lower in weeds than in seeded forages.

예취빈도 및 질소수준이 혼파초지에 미치는 영향 2 . 예취 및 N의 효율 , 식생구성비율 , N의 함량 및 회수율

정연규,윤상기,이종열 ( Yeun Kyu Jung,Sang Gi Yun,Jong Yeal Lee ) 한국축산학회 1981 한국축산학회지 Vol.23 No.6

This field experiment was undertaken to assess the effects of cutting frequency (3, 4, 5, 6 times) and N rate (0, 15, 30, 40 ㎏/l0a) on the efficiencies of cutting, the efficiency of the N, the botanical composition, and the percentage recovery and content of N of different forage species and mixed forages within a mixed grass/clover sward, 1. By increasing the cutting frequency, the efficiency of cutting(DM ㎏ per cut) to grass and total yields was reduced, whereas with legumes yield did not change or increased slightly until 5 cuttings. At 6 cuttings it reduced, Efficiency of weed yield was highest with 5 cuttings, 2. The efficiency of N (DM ㎏ per ㎏ N) to grass and total yield was highest with 15㎏ N at all cutting frequencies, It was reduced by increasing the N rate over 15㎏ N, N application to legume yield had minus value with the lowest at 15 ㎏ N, This minus value was lower under frequent cutting, 3. The ratio of grass/clover was greatly increased by increasing the N rate, but this increase was eliminated by increasing the cutting frequency, This ratio was further reduced by increasing cutting until 5 cuttings, which was the lowest. At the 6 cuttings, there was a small increase in the ratio 4. By increasing cutting (spring-summer-autumn), grass was reduced and legume increased. 5. Percentage recovery of N in the mixed sward was increased by increasing the cutting, This was mainly due to the increasing N content in the mixed forage according to the increased ratio of legume and by cutting at a younger stage, and the efficiency of N etc. 6. The efficiencies of cutting and the efficiency of N, the grass/clover ratio, the percentage recovery and the content of N in a mixed sward were all differentially influenced by botanical composition, cutting frequency, N rate and the interaction between all of these factors.

석회 및 3 요소 시용수준이 겉뿌림 산지초지에 미치는 영향 1 . 토양특성 , 초기생육 , 총 건물수량 및 내용연한의 변화

정연규,박병훈,이종열 ( Yeun Kyu Jung,Byung Hoon Park,Jong Yeal Lee ) 한국축산학회 1982 한국축산학회지 Vol.24 No.6

This field experiment was undertaken to assess the effects of two rates of Ca(OH)₂ (0, 250 Kg/l0a) and five rates of N-P₂O_5-K₂O (0-0-0, 0-10-10, 6-15-15, 12-20-20, 24-25-20 Kg/l0a) on the grassland establishment, forage yield and quality, botanical composition, and persistence of different forage species in a mixed grass/clover sward established by oversowing method on new reclaimed steep mountain. This first part is concerned with the soil properties, vigour of early growth, total yield of mixed forages, and persistence of grassland. The results obtained were summarized as follows; 1. Organic matter in soil was increased by both landuse of grassland and liming. Liming raised pH, increased P and Ca, and reduced Mg in soil, whereas that had inconsistent effect on concentrations cf K and Na. Organic matter, pH, P, Ca, Mg, and K in soil after a 7-year experiment were lower at the optimum rate of NPK than at the low rate. 2. The vigour at early growth of forages was enhanced by liming. Averaging over all NPK treatments and 7 experimental years, the yearly mean yield of mixed forages was increased 21% by liming over no lime. The only one-time liming at establishment of oversown grassland had consistent effect on the yield during 7 experiment years without depression of lime effiency. By increasing the NPK rate, emergence and early growth of seeded forages were enhanced, and yields of mixed forages were greatly increased. 3. The oversown grassland in mountainous area was well established and had high yielding during 7 experiment years with both liming at establishment and 24-25-20 (N-P₂O_5-K₂O) Kg/l0a/year. Lowest application rates of N-P₂O_5-K₂O to perform the economical yielding of oversown grassland ($gt;650 Kg/l0a in DM, and$gt;50% in rate of seeded forages) were 12-20-20Kg/l0a rate at no lime and 6-15-15 at lining.

예취빈도 및 질소수준이 혼파초지에 미치는 영향 1 보 . 건물수량 및 수량구성요소의 변화

정연규,윤상기,김상철,이종열 ( Yeun Kyu Jung,Sang Gi Yoon,Sang Chul Kim,Jong Yeal Lee ) 한국축산학회 1981 한국축산학회지 Vol.23 No.4

This field experiment was undertaken to assess the effects of cutting frequency (3,4,5,6 times) and N rate (1,15,30,40 ㎏/l0a) on the yield and persistence of different forage species within a mixed grass/clover sward. 1. Under frequent cutting, dry matter yields of grasses were usually reduced at all of the rates of N, whereas yields of legumes generally increased except at a cutting frequency of 6 at the low rate of N. Weeds increased at high rate of N and reduced at the low rates. Total yield was highest with 4 cuttings. 2. By increasing the N rate, yields of grasses, weeds and the total yield were increased at all cutting frequencies, whereas yields of legumes were reduced. N fertilizer had a greater effect on grass yield than on weeds, so the percentage of weeds in the sward was reduced as a result of fertilizing with N. 3. Optimum cutting frequency and N rate were correlated with each other. Grass and total yields were highest with 4 cuttings and 30 N, legume was highest with 5 cuttings and O N, and weeds was highest with 5 cuttings and 40 N. Generally, infrequent cutting and high rate of N had negative effects on clover and weeds. 4. At the low rate of N, yields of grass and weeds, and total yield were highest with infrequent cuttings. At the high rate of N, the yield of legume was highest with frequent cuttings. 5. Yields of grass, legume and weeds in mixed sward were differentially influenced by cutting and N fertilizer (main effects and interaction = P $lt; 0.01).