Popis článku
Rozdílný průběh teplot na vrchní a spodní straně jehličí výhonů sazenic jedle v jarním období.[Different run of temperature on upper and lower side of shoots of European fir seedlings in spring] 66 - 71.
Název článku: | Rozdílný průběh teplot na vrchní a spodní straně jehličí výhonů sazenic jedle v jarním období |
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Číslo: | 1 |
Rok: | 2014 |
Autor: | Ondřej Špulák |
The paper aims to evaluate the temperature dynamics of upper and lower side of shoots of European fir seedlings during spring. Calibrated miniature thermocouples were stuck to the upper and lower surface of needles on shoots of six young firs ca 45 cm in height (i.e. six replications). Two sunny periods with frosts and one overcast period with rain were evaluated. Temperatures were recorded every minute. Data were evaluated in relation to air and soil temperatures, global radiation, wind speed and precipitation recorded every hour. In sunny days, temperatures of upper side of shoots were higher compared to lower side, with maximum difference in about 11 a.m. During cloudless nights, temperatures of lower side of shoots were higher. Afternoon and night temperatures of the lower side of shoots in clear days were increased by convection from soil surface. In cloudy days with rain, the temperature differences during day and night were insignificant. Wind decreased temperature differences in daily and night hours.