抄録
A new equipment with an open chamber for measuring evaporation rate from the soil surface is described in this paper. The chamber differs from commonly used chambers due to the fact that it is completely open at the entrance. The chamber covers a ground area of 0.6 m2 and has a volume of 0.3m3. A suction arrangement has been used in passing air through the system and the ventilation rate can be regulated up to a maximum value of 90 m3/h. The evaporation rate measured by the equipment showed good agreement with the evaporation rate measured by a balance both in the laboratory and the field. The net solar radiation was reduced by about 6% due to the chamber. The soil moistureunder the chamber showed good agreement with the simulated values as well as with the soil moisture measured outside the chamber. The pressure difference within and outside the chamber was found to be negligible. The open chamber system minimizes its influence on the natural environment and thus gives better measurements.
