Wpływ warunków meteorologicznych na strumień ciepła w glebie

Daily sum of positive (directed into soil) heat flux relationships with meteorological elements were analysed basing on the data collected during the summer days without rainfall on the fields with bare soil. The soil heat flux density (at 1 cm depth) in the daily course was calculated by means of a combined method, i.e. from the heat storage changes within 1-20 cm layer of soil (at half-hour steps) and the soil heat flux at 20 cm depth determined by the gradient method. The meteorological data contained : sunshine duration, cloudiness, water vapor deficiency, wind speed, mean daily air temperature, daily air temperature amplitude and air temperature mean value changes from day to day. The regression equations between sums of positive soil heat flux and the meteorological data combinations, as well as the determination coefficients and standard errors of estimation were established. It was stated, that to estimate daily sum of heat flux into soil on the basis of meteorological elements it is more reasonable to use the equation with only three most important meteorological data (sunshine duration, air temperature amplitude and air temperature changes from day to day) than with all of them.