[Variations of canopy temperature in Quercus variabilis plantation and their relations with micrometeorological factors].

Based on the canopy temperature and micrometeorological data of Quercus variabilis in its main growth season (from May to August) in hilly areas of North China in 2011, this paper analyzed the variations of canopy temperature (T(c)) in Q. variabilis plantation and their relations with micrometeorological factors in typically clear days and cloudy days. From 9:00 to 17:00 in clear days, the boundary layer of canopy was unstable, and the mean T(c) was 3.55 degrees C higher than the mean air temperature (T(a)). In cloudy days, the variations of T(c) were gentler than those in clear days. The T(c) was significantly correlated with T(a), net solar radiation (R(n)), relative humidity, and wind speed, with a multiple correlation coefficient being 0. 825. The T(a) and R(n) were the dominant meteorological factors controlling T(c), and their affecting degree on T(c) was associated with weather condition.