Daily Changes in Red-Pepper Leaf Surface Temperature with Air and Soil Surface Temperatures

엄기철,이병국,김영숙,엄호용 한국토양비료학회 2014 한국토양비료학회지 Vol.47 No.5

This study was conducted to investigate the changes in daily surface temperature of red pepper leaf comparedto air and soil surface temperature. The maximum, minimum and average daily temperatures of red pepper leafwere 27.80, 11.40 and 19.01°C, respectively, which were lower by 0.10, 7.60 and 3.86°C than air temperature,respectively, and lower by 15.00, 0.0 and 4.38°C than soil surface temperature, respectively. Mean deviationsof the difference between measured and estimated temperature by the E&E Model (Eom & Eom, 2013) for theair and surface temperature of red pepper leaf and soil were 0.64, 1.82 and 4.77°C, respectively. Therelationships between measured and estimated scaled factor of the air and surface temperature of red pepperleaf and soil were very close to the 1:1 line. Difference between air and surface temperature of red pepper leafshowed a linear decreasing function with the surface temperature of red pepper leaf. Difference between soilsurface temperature and air and surface temperature of red pepper leaf linearly increased with the soil surfacetemperature.

토양수분함량 측정 방법별 오차분석에 의한 비교

엄기철,유관식,엄기태 한국토양비료학회 1988 한국토양비료학회 학술발표회 Vol.1988 No.40

수도권 과밀의 진단과 처방 수도권의 변모 현황과 문제

엄기철 대한지방행정공제회 1989 도시문제 Vol.24 No.5

N/A

국토확장 - 얻는 것과 잃는 것

嚴基哲 세계평화교수협의회 1984 廣場 Vol.1984 No.135

한국어 조사 '이/가', '을/를'의 기능과 의미 연구 : 격조사의 설정 여부를 중심으로

엄기철 동국대학교 국어교육과 2002 동국어문학 Vol.14 No.-

삼각함수 및 극좌표와 Scaling technique에 의한 기상 Data의 새로운 해석

엄기철,김이열,임채일,박용환,박민서 한국기후변화학회 2020 한국기후변화학회지 Vol.11 No.5

This study focus on a new data analysis method using trigonometric function, polar coordinate, scaling technique. The principle results are as follows : (1)Yearly variation is greater than 10-day variation for mean air temperature and mean relative humidity. (2) Models of maximum relative humidity, mean relative humidity and minimum relative humidity were developed using the trigonometric function Y = a sin [ b (X = c) (Pi / 720) ] + d. (3)Balance and dependence between mean air temperature and mean relative humidity are analyzed based on distance and angle in polar coordinate. (4)The change ratio of balance angle in polar coordinate according to mean air temperature is a function of that temperature, but the ratio according to scaled factor is constant.

우리나라의 잠재증발산량 변동양상 예측모형 개발

엄기철,정필균,김태완,유성녕,박소현 한국토양비료학회 2011 한국토양비료학회지 Vol.44 No.5

The model to estimate potential evapotranspiration (PET) was developed using periodic function. Average PET during 30 years for 67 areas was 2.36 mm day^-1, and those were distributed with the range of 1.42∼3.45 mm day^-1. The period of PET change was 16∼32 years according to area.

Species Diversity Analysis of the Aquatic Insect in Paddy Soil

엄기철,한민수,이병국,엄호용 한국토양비료학회 2013 한국토양비료학회지 Vol.46 No.3

The aquatic insect collected at six areas (each 2 for mountain area, plain field, and urban area) from 2009to 2011 were classified to analyze the distribution and diversity of species. Frequency (number of aquatic insect: N), number of species (S), similarity index (C), richness index (R1, R2), variety index (V1, V2),evenness index (E1, E2, E3, E4, E5), and dominance index (D1) were investigated. Total N and S were 143 and 84, respectively. C matrix of 153 combinations was constructed with the average of 0.542. The average C of 3 years (0.659) was 9.9% P , more higher than the average C of 6 areas (0.560). The average values of the index of 18 plots were 2.28, 0.17, 1.24, 1.08, 0.07, 0.06, 0.01, 0.87, 0.31, 0.93 for R1, R2,V1, V2, E1, E2, E3, E4, E5, D1, respectively. The order in the coefficient of variation (CV) of the indicator for 18 plots was N (70.0%) > E3 (54.9%) > E1 (49.6%) > R2 (40.5%) > S (35.3%) > R1 (33.7%)> E2 (28.4%) > E5 (15.9%) > V1 (11.1%) > E4 (6.3%) > V2 (5.1%) > D1 (4.8%). The correlation matrix with 66 combinations between the indexes was constructed with statistical significance for 33combinations. However, R1, V1, E2 and D1 were the proper indexes to represent species diversity of aquatic insect based on the correlation matrix and the theory of statistical independence. The richness index was highest in mountain, variety index in urban area, and evenness index in plain field. However,the dominance index was lowest in urban area.

봄배추의 시비반응(施肥反應)에 미치는 토양수분(土壤水分) Potential의 영향(影響)

엄기철,손응용,유순호,Eom, Ki-Cheol,Son, Eung-Ryong,Yoo, Sun-Ho 한국토양비료학회 1983 한국토양비료학회지 Vol.16 No.2

토양수분조건에 따른 시비반응을 구명(究明)하기 위하여 본량(本良) 사양토(砂壤土)에서 토양수분처리($M_0$무관수, $M_1$-0.1~-1.0bar, $M_2$-0.1bar~-0.5bar, $M_3$-0.1~-0.2bar)와 시비수준(施肥水準)(N-P-Kkg/10a, 0-0-0, 11.5-10-12.5, 23-20-25, 34.5-30-37.5)을 달리하여 봄배추의 생육상태(生育狀態), 물소모량(消耗量), 양분흡수량, 비료이용율(肥料利用率), 수량 등을 조사(調査)한 결과(結果)는 다음과 같다. 1) 20cm 깊이에서 토양수분 Potential이 -2.0bar 이하(以下)일 때 물소모량은 감소(減少)하였고 비료(肥料)에 의(依)한 생장량(生長量)의 증가는 없었다. 2) 배추의 양분흡수량(養分吸收量)은 시비량(施肥量)의 증가에 따라 토양수분 Potential이 낮을 때는 감소(減少)하는 경향(傾向)이었고, 토양수분 Potential이 높을 때는 증가하는 경향(傾向)이었다. 3) 질소(窒素)와 가리(加里)의 이용율(利用率)은 토양수분 Potential과 시비수준(施肥水準)이 정비례관계(正比例關係)에 있어야 이용율(利用率)이 증대되었다. 4) 봄배추의 수량(收量)은 토양수분 Potential이 낮을 때에는 시비량(施肥量)을 증가시켜도 증수가 없었으며, 토양수분 Potential이 높을 때에는 각(各) 시비수준(施肥水準) 공(共)히 증수효과(增收效果)가 있었고 그 효과(效果)는 다비수준(多肥水準)에서 더욱 뚜렷하였다. 5) 토양수분 Potential을 높게 유지(維持)시킬 경우(境遇)에는, 시비량(施肥量)을 증가시킴에 따라 봄배추 수량(收量)이 거의 직선적(直線的)인 증가경향을 보여, 최대수량을 낼 수 있는 비료요구량(肥料要求量)이 크게 증가되었다. Differences in fertilizer responses of Chinese cabbage to soil water status were investigated in a field experiment. The growth pattern, water use, nutrient uptake, apparent efficiency of fertilizer and yield were analyzed under the 4-different fertilizer levels (N-P-K rate, kg/10a: 0-0-0 Fo, 11.5-10-12.5 Fo.5, 23-30-25 F1.0, 34.5-30-37.5 F1.5 and under the 4-different soil water status levels (non irrigated plot Mo, -0.1 to -1.0 bars M1, -0.1 to -0.5 bars M2, -0.1 to -0.2 bars M3). The soil was Bonryang sandy loam in the experimental farm of the Institute of Agricultural Sciences, Suweon. The growth and yield responses to the fertilizer levels showed a large difference between F0 and F0.5 but little differences were recognized between F0.5, F1.0 and F1.5 when the soil water potentials at 20-cm soil depth were lower than -2.0 bar. Under the well irrigated soil conditions, M2, and M3, the growth and yield responses to the fertilizer levels were significantly increased and the nutrient requirements were increased as well. The total uptake of nutrients decreased as the fertilizer amounts increased when the soil water potentials were low, while the total uptake of nutrients increased when the soil water potentials were high. Therefore, in considering nutrient availability of the applied fertilizers, the soil water status should be taken into account.

Yield Response of Soybean to Drought Stress under Different Fertilizer Level

엄기철,정필균,고문환,김영숙,이경은 한국토양비료학회 2013 한국토양비료학회지 Vol.46 No.4

This study was conducted to investigate the yield response of soybean to drought stress in 1984 and 1986 at the experiment field of the National Academy of Agricultural Science using experiment plots with different soil water tension and fertilizer levels. The average yield response factor (YRF) of soybean to evapotranspiration (ET) calculated as [(Ya/Ym)/(ETa/ETm)], where Ya, average yield; Ym, maximum yield; ETa, average ET; and ETm, maximum ET, was 0.91 with the range from 0.74 to 1.16. Relationship between yield index (YI = [Ya/Ym]) and evapotranspiration index (ETI = [ETa/PET]) was YI = 0.87·(ETI) + 0.09. Relationship between YI and the maximum soil water tension (Hmax) was YI = 1.23 - 0.23·log (Hmax). Relationship between YI and the days of drought stressed (Dr) was YI = 0.877·exp (-0.01·Dr). The relation between YI and fertilizer level (F) was YI = -0.21·F2 + 0.36·F + 0.33, under very serious drought condition as the maximum soil water tension was 0.3 MPa.