Changes in Barely Yield and Soil Physcio-Chemical Properties Affected by Long-Term Fertilization to the Upland Soil

밭토양(土壤)에서 삼요소(三要素) 장기연용(長期連用)에 의(依)한 대맥(大麥) 수량(收量) 및 토양(土壤)의 이화학적(理化學的) 성질변화(性質變化)

A long term fertilizer trial has been conducted on a silty clayloam soil with barley as test crop since 1975. The treatments included NPK, NK, NP, and PK, and no fertilizer. This paper is to report the barley yield trend during 16 years(1975~1990) and the soil chemical properties and nutrient uptake by barley in 1990. Following is the summary of the results. 1. The average yield of barley in 16 years were in the order of NPK(100%) > PK(69%) > NP(55%) > No Fertilizer(35%) > NK(24%). Of special interst was that in 16th year the yield of barley in NK plot, namely without P, was nil. 2. In NK plot where the yield of barley was nil in 16th year, the uptake of N, P, and K by plant was lowest amomg the treatments and N, K fertilizer uptake efficiencies were nagative. 3. The soil analysis in 16th year revealed that in NK plot the pH, the available P and exchangeable Ca and Mg were very low. In 16 years average, there was positive correlation between the yield of barley and available P and exchangeable Mg in the soil. One interesting point was that in 16th year the $NO_3-N$ in the soul was relatively high, but N uptake by barley was very low.

밭토양(土壤)에서 비료(肥料)의 장기(長期) 연용(連用)이 대맥(大麥)의 생육(生育) 및 수량(收量)에 미치는 영향(影響)을 구명(究明)코자 미사질(微砂質) 식양토(埴壤土)인 우평통(牛坪統)에 무비(無肥), P.K, N.K, N.P 및 N.P.K구(區)를 처리(處理)하여 1975~1990년(年)까지 16년간(年間)의 년차간(年次間) 수량변화(收量變化), 16년차(年次) 수확기(收穫期) 식물체(植物體) 부위별(部位別) 양분흡수량(養分吸收量) 및 토양성질(土壤性質) 변화(變化)를 조사(調査)한 결과(結果)는 다음과 같다. 1. 삼요소(三要素) 대조구(對照區)에 비(比)하여 각요소(各要素) 결제구(缺除區)의 수량감수정도(收量減收程度)는 P.K$P_2O_5$와 $K_2O$ 흡수량(吸收量)이 전처리중(全處理中) 가장 적었고 특(特)히 N와 $K_2O$의 흡수이용률(吸收利用率)은 부(負)의 수치(數値)를 보였다. 4. 시험후(試驗後) 토양분석결과(土壤分析結果) N.K 처리구(處理區)에서 토양(土壤) pH가 매우 낮았고, 또한 토양중(土壤中) $P_2O_5$, Ca, Mg 함량(含量)은 매우 적었으며, 16년간(年間) 평균토양중(平均土壤中) 인산(燐酸) 및 고토함량(苦土含量)과 대맥수량(大麥收量)과는 정(正)의 상관(相關)을 보였으나, 16년차(年次) 시험(試驗) 후(後) 토양중(土壤中) $NO_3-N$ 함량(含量)은 매우많은 반면(反面) 식물체(植物體) 질소(窒素) 및 기타(其他) 성분(成分) 흡수량(吸收量)은 매우 적었다.