Thermal pulse sap flow or water flux density measuring apparatus capable of correcting space and measuring method

Abstract

The invention reveals a thermal pulse sap flow or water flux density measuring apparatus capable of correcting space and a measuring method. The measuring apparatus comprises a base, temperature probes and a heating probe, wherein the temperature probes and the heating probe are fixed on the base, a first temperature measurement element and a second temperature measurement element are respectively arranged in each temperature probe along the axis direction of the temperature probe, the two temperature measurement elements are both connected with a data acquisition device, and a heating wire is arranged in the heating probe and connected with a heating device. According to the measuring apparatus and the measuring method provided by the invention, each temperature probe employs at least two temperature measurement elements, so measurement errors of sap flow in plants or water flux density in soil caused by bending deformation of the temperature probes or heating probes due to external causes in practical application are reduced. Moreover, the apparatus has the advantages of a simple structure, low cost, convenience in usage and rapid and accurate measurement.

Description

technical field [0001] The invention relates to the field of measurement technology, and more particularly relates to a thermal pulse stem flow or water flow measurement device and method capable of correcting spacing. Background technique [0002] Measurement of soil water flux. [0003] The measuring device for measuring water flux by thermal pulse method includes three parallel stainless steel probes, the heating probe in the middle position, and the other two are temperature probes equipped with temperature measuring elements, which are arranged on both sides of the heating probe, respectively For upstream temperature probes and downstream temperature probes such as figure 1 As shown in , the maximum value of the temperature difference recorded by the upstream and downstream temperature probes was used to estimate the water flux in the soil. [0004] Under steady-state water flow, the heat conduction equation is: [0005] ∂ T...

AI Technical Summary

Problems solved by technology

However, in practical applications, whether it is for stem flow measurement or soil water flow measurement, it is easy to cause the temperature probe to be deformed by external forces and other factors

For example, when measuring the stem flow of trees, if the method of punching holes in advance is used, due to technical problems, it is easy to cause the temperature probe spacing to deviate from the original spacing. In addition, factors such as tree growth will eventually lead to the measured tree stem flow Flow measurements are subject to large errors

For the measurement of soil water flux, the temperature probe or heating probe may be bent due to foreign matter in the soil, such as the existence of stones, tree roots, alternation of freezing and thawing, and distortion during installation; the above All situations change xu and xd, so that the calculated stem flow or water flux deviates greatly from the actual stem flow or water flux

Images