Jin-Il Yun, Kyung-Sook Cho, Heon Hwang, Eun Woo Park, and Seong-In
Cho. 1998. Estimating microclimatic elements of a fully developed paddy
rice canopy based on standard weather data. Korean J. of Meteorology 34:216-221
Please note this article was published in Korean and is not included
in these pages.
Air temperature(Ti) and dew point temperature(Tid) within a paddy rice
canopy, which are closely related to major disease pests onset, were estimated
from a standard weather data by using simple regression schemes:
Ti = 4.08 + 1.48F + 0.8To + 0.034RHo
Tid = -62.7 + 0.71F + 0.158RHo + ln(To)
where To and RHo are observed air temperature and relative humidity
at a nearby standard weather station, respectively. F is hourly temperature
deviation between the within-canopy and the standard weather station a
time t, and can be expressed as a Fourier function with a form of
F = -0.2 + 0.8cos(0.2618(t - 12)). The coefficients of determination were
0.86 and 0.69 at 99% confidence level for tempearture and dew point equation,
respectively. According to a CART (classification and regression tree)
analysis, dew is assumed to be present on rice leaves if dew point depression
is below 0.96C. Independent data sets were used to evaluate the schemes
for estimating microclimates of paddy fields during the stem elongation
period (from maximum tillering to heading stage) of rice plants. Results
showed a stron feasibility of using these schemes for converting standard
weather data to canopy microclimate data regardless of the sky condition.
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