Method of determining value of transpiration stream in plants and apparatus for making the same

No information given. When employing the invented method of determining transpiration stream in plants by measuring deformation of temperature field, first a temperature field is created in a portion of a plant skeleton around section of axis forming with a transversal plane an angle ranging from 0 to 45 degrees , whereupon heat propagation in axial and tangential direction is measured, whereby there is measured both the temperature difference within the temperature field between the first measuring point above the axis section and the second measuring point beneath the axis section, where the first and the second measuring points are situated in an axial plane passing through the axis section and the distance thereof from the axis section is equal, and the temperature difference between the third measuring point and the fourth measuring point being both arranged at a small tangential distance from an axial plane passing through the first and the second measuring points, whereupon the value of temperature difference between the first and the second measuring points is divided by the value of temperature difference between the of third measuring point and the fourth measuring point and the result is multiplied by a constant taking in account the skeleton thermal conductivity, specific heat of water, and mutual arrangement of the measuring points. The apparatus for making the above described method comprises four thermometers (2, 3, 4, 5) being situated at measuring points, a heat source (1) placed within the axis section and a measuring central unit to which the thermometers (2, 3, 4, 5) are connected.