Microclimate and evapotranspiration in two wet grassland communities

Abstract

Vertical profiles of soil temperature and of the dry and wet bulb temperature of the air, relative humidity and wind velocity were measured within and above stands ofJunco-Molinietum Preising 1951 (facies ofDeschampsia caespitosa) andCaricetum gracilis Almquist 1929 on selected sunny days during the growing season. Evapotranspiration was computed by means of the heat-budget equation. The principal difference between the two communities has been found in the soil temperature. The stand of theCaricetum gracilis occupies a habitat with a cooler soil and with a higher ground water level than the stand of theJunco-Molinietum coeruleae, facies ofDeschampsia caespitosa. The evapotranspiration per unit ground area was higher by some 20% in theCaricetum gracilis. The evapotranspiration per unit above-ground biomass was much the same in both communities.