Abstract
To find out the optimum split application ratios of fertilizer nitrogen and potassium in the newly opened pasture at spring, a field experiment was conducted. Two levels of nitrogen and potassium application and three split application ratios of both fertilizer were treated by split design with 4 replications. The experiment was carried out from March, 1984 to October, 1985 on the experimental field of the Livestock Experiment Station in Suweon. The results obtained are summarized as follow: 1. Total DM yield was not showed signigicant difference among split application ratios of nitrogen and potassium. 2. DM yield of grasses was 4,854 kg/ha in heavy basal application of N and $K_2$O (160 kgN: 140 kg $K_2$O/ha), it was significantly increased by 16% than of conventional dressing (80 kg N: 70 kg $K_2$O/ha). But there was almost no difference in dry matter among N and $K_2$O split application ratios. 3. Dry matter yield of legume in heavy basal dressing was decreased by 23% than that of conventional dressing. In the methods of NK application, dry matter yield of legume was tended to decrease by 3% with equal application and 9% with heavy dressing in autumn, when compared with that of heavy dressing in spring. 4. There was no significant difference in dry matter yield of native species between different basic fertilization levels, but dry matter yield of native species was decreased by 6% with equal application and more increased by 11% with heavy dressing in autumn, when compared with the yield of heavy dressing in spring. 5. In aspect of the botanical composition, the percentage distribution of grasses was increased and the ratio of legume was greatly decreased by heavy dressing at basal fertilization. Also for good maintenance of botanical composition, it is suggested that the equal split application of N and $K_2$O was desirable.
본(本) 시험(試驗)은 춘파초지조성시(春播草地造成時) 목초(牧草)의 정착(定着)과 수량(收量) 및 식생변화(植生變化)를 조사(調査)하기 위(爲)하여 조성시(造成時)의 기비량(基肥量)을 2수준(水準)($N:P_2O_5:K_2O=80:200:70$ 및 160:200:140kg/ha), 관리시(管理時)의 질소(窒素) 및 가리(加里) 분시방법(分施方法)을 3수준(水準)(봄 다비(多肥), 균등분시(均等分時), 가을 다비(多肥))으로 하여 분할구법(分割區法) 4반복으로 포장(圃場) 배치(配置)하여 1984년 3월부터 1985년 10월까지 축산시험장(畜産試驗場)에서 실시(實施)하였던 바 그 결과(結果)를 요약(要約)하면 다음과 같다. 1. 총(總) 건물수량(乾物收量)은 조성시(造成時)의 기비수준(基肥水準)이나 관리시(管理時)의 분시방법간(分施方法間)에 대차(大差)없었다. 2.화본과목초(禾本科牧草)의 총(總) 건물수량(乾物收量)은 조성시(造成時) N=160, $P_2O_5=200$ 및 $K_2O=140kg/ha$ 시용(施用)한 처리(處理)가 4,854kg/ha로서 보비(普肥)에 비(比)해 16% 증수(增收)되었으며 분시방법간(分施方法間)에는 별차이(別差異)가 없었다. 3. 두과목초(荳科牧草)의 총(總) 건물수량(乾物收量)은 조성시(造成時) 증시(增施)한 구(區)가 보비(普肥)에 비(比)해 23% 감소(減少)되었으며 분시방법간(分施方法間)에서는 봄 다비(多肥)에 비(比)해 균등분시(均等分施)는 3%, 가을다비(多肥)는 9% 감소(減少)되었다. 4. 야초(野草)의 건물수량(乾物收量)은 조성시(造成時)의 기비수준(基肥水準)에는 대차(大差)없었으나 분시방법(分施方法)에서는 봄 다비(多肥)에 비(比)해 균등분시(均等分施)는 6% 감소(減少)되었고 가을 다비구(多肥區)는 11% 증가(增加)되었다. 5. 식생구성비율(植生構成比率)에 있어서 조성시(造成時)의 다비(多肥)는 보비(普肥)에 비(比)해 화본과(禾本科)는 증가(增加)되었고 두과(荳科)는 감소(減少)되었으며 분시방법(分施方法)에 있어서는 균등분시(均等分施)가 비교적(比較的) 양호(良好)하였다. 6. 이상(以上)의 결과(結果)를 종합(綜合)해 볼 때 춘파초지조성시(春播草地造成時)의 목초(牧草) 정착(定着)을 위(爲)한 기비량(基肥量)은 N : 160, $P_2O_5$ : 200 및 $K_2O$ : 140kg/ha가 수량(收量) 및 식생유지면(植生維持面)에서 좋을 것으로 생각되며 분시방법(分施方法)은 균등분시(均等分施)가 좋을 것으로 사료(思料)된다.
