T-max plant stem flow measuring method and device thereof

Abstract

The invention relates to a T-max plant stem flow measuring method and a device thereof. A heater is arranged on a plant stem; a detection temperature sensor is arranged at a position with a distance of XD from the heater at the downstream of the stem flow on the stem; a compensation temperature sensor is arranged on the stem, which is not influenced by the thermal pulse, at the upstream or downstream of the stem flow; the detection temperature sensor and the compensation temperature sensor form a temperature difference detector; a heating controller is reset and starts a timer after controlling the heater arranged on the plant stem to emit the thermal pulse for heating the plant stem; a temperature difference signal acquired by the temperature difference detector finds a peak point of thetemperature different signal out by preamplification, gain amplification, lowpass filtering, half-wave rectification, alteration index amplification, threshold detection, differentiation and zero-crossing detection; and the timer is turned off at the peak point; and a time recorded by the timer is substituted in the stem flow computing formula of the T-max method so that the capacity of measuringthe low-speed stem flow by using the T-max method is greatly improved. The T-max plant stem flow measuring method and the device thereof have the advantages of low cost, high precision, high reliability, little heat flux, wide measurement range and convenient use.

Description

Technical field: [0001] The invention relates to a method and a device for measuring plant sap flow by adopting heat pulse tracing technology, in particular to a T-max method for measuring plant sap flow and a device thereof. Background technique: [0002] During the transpiration process of plants, the water absorbed by the root system from the soil is continuously transported to the leaves through the stem flow of the plant, and finally emitted to the atmosphere through the stomata of the leaves. During this process, the liquid in the stem of the plant is always in a state of flow , and the size of plant stem flow can reflect the change of plant transpiration, so the method of measuring plant stem flow can determine the transpiration water consumption of plants. There are many methods to measure plant stem sap flow with marker tracer, the more common ones are isotope tracer method and thermodynamic method. [0003] The thermodynamic method or thermal technology method can...

AI Technical Summary

Problems solved by technology

Because the mechanical contact of the relay has pull-in action delay, individual differences and fatigue errors, it cannot be ignored for the heating time of only a few tenths of a second, which affects the precise control of the heating amount

[0007] The above traditional T-max plant sap flow measurement device has low heating accuracy and high cost, especially the ability to measure low-speed sap flow is even worse, and has a tendency to gradually fade out of the application field. It is urgent to adopt updated technical solutions to obtain better Superior technical performance and lower production costs

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