Abstract
This field experiment was undertaken to assess the effects of three levels of inclination ($10^{\circ},\;20^{\circ},\;and\;30^{\circ}$) and four rates of $N-P_2O_2-K_2O$ (O-O-O, 14-10-20, 28-25-25, and 42-40-40kg/10a) on establishment, forage yield and quality and botanical composition of new established mixed grass-clover sward. This first part is concerned with the forage yield, yield component and botanical composition. The results obtained after a two-year experiment are summarized as follows: 1. Dry matter yields of mixed grass-clover sward were greatly decreased by increasing the inclination grade of hilly pasture, whereas it of weeds was not significantly influenced. Comparing with weeds, the establishment of introduced pastures was relatively low with increasing the grade of inclination. 2. By increasing the NPK rate, the yields of grasses and mixed forages and the rate of introduced pastures were greatly increased at all grades of inclination, whereas the change in the weed yield was not significant. 3. There were the differenced in the forage yield and yield component, and efficiency of fertilizers by the grade of inclination, which indicated the necessity of different management on the selection of suitable grass species, seeding rate, amount of fertilizer application, and the methods of grassland establishment, management and utilization.
산지경사도(山地傾斜度)($10^{\circ},\;20^{\circ},\;30^{\circ}$) 및 3요소(要素)($N-P_2O_5-K_2O$) 시용수준(施用水準)(0-0-0, 14-10-10, 28-25-25, 42-40-40kg/10a) 별(別) 겉뿌림 산지초지(山地草地)의 조성(造成), 생산성(生産性), 식생(植生) 및 목초품질등(牧草品質等)에 미치는 영향(影響)을 구명(究明)하였다. 식생구성비율(植生構成比率)에 관(關)해 검토(檢討)하였다. Orchardgrass, Tall fescue, Redtop, Ladino clover를 혼파(混播) 수년초지(水年草地)의 2년간(年間) 시험결과(試驗結果)는 ; 1. 경사도(傾斜度)가 증가(增加)함에 따라서 총건물수량(總乾物收量), 구성초종중(構成草種中) 화본과목초(禾本科牧草) 및 두과목초(荳科牧草)의 수량(收量)은 유의성(有意性)있게 크게 감소(減少)되었으나 잡초수량(雜草收量)은 유의차(有意差)가 없었다. 또한 경사도(傾斜度)가 높아짐에 따라서 파종목초(播種牧草)의 정착율(定着率)이 잡초(雜草)에 비(比)해서 상대적(相對的)으로 낮았다. 2. 3 요소수준(要素水準)의 증가(增加)는 총수량(總數量), 구성초종중(構成草種中) 화본과목초(禾本科牧草)의 수량(收量) 및 목초율(牧草率)을 크게 증가(增加)시켰으나, 잡초(雜草)의 수량변화(收量變化)는 경미(輕微)하였다. 두과목초(荳科牧草)의 수량(收量)은 질소(窒素) 소비수준(少肥水準)에서 가장 높았으며 높은 3 요소수준(要素水準) (특(特)히 질소영향(窒素影響))에서는 감소(減少)되었다. 3. 경사도(傾斜度)에 따라서 생산성(生産性), 수량구성요소(收量構成要素) 및 시비효율이 다른 특성(特性)을 나타내므로 혼파초종(混播草種)의 선택(選擇), 파종량(播種量), 시비량(施肥量), 초지조성(草地造成) 및 관리이용(管理利用) 방법(方法)에 차이(差異)를 두어야 할 것이다.
