Method and system for continuously monitoring water conductivity of xylem of woody plant in situ

Abstract

The invention discloses a method and a system for continuously monitoring the water conductivity of xylem of a woody plant in situ. The method comprises the following steps: S1, respectively measuringwater potential psi s and up at the upper end and water potential [psi]s and down at the lower end of the xylem by adopting a stem water potential instrument; S2, measuring the xylem liquid flow rateQ based on a heat balance principle or a heat pulse principle; and S3, monitoring the xylem water conductivity Kh according to the xylem water potential and the liquid flow flux, wherein the xylem water conductivity Kh is equal to Q / (dP / dx), Q is the liquid flow flux, dP is the water potential difference between the upper end and the lower end, dP is equal to [psi]s, up-[psi]s, down and dx are the length of a liquid flow path. According to the method, independent and continuous water potential and liquid flow measurement is combined, the water conductivity of the woody plants is continuouslymeasured in situ according to a water conductivity calculation formula, basic data support can be provided for calculation of the specific conductivity, the leaf specific conductivity and the embolization threshold value of the plants, and a firm and reliable new method is provided for hydraulic development of the plants.

Description

technical field [0001] The invention belongs to the technical field of xylem hydraulic conductivity observation, and in particular relates to a method and system for in-situ continuous monitoring of xylem hydraulic conductivity of woody plants. Background technique [0002] Xylem hydraulic conductivity is defined as the liquid flow through plant xylem under unit pressure gradient per unit length and unit time. As an important indicator of plant hydraulic structure characteristics, it is widely used in related studies such as plant water transport, xylem embolization, and drought tolerance. . [0003] At present, the commonly used methods for measuring the hydraulic conductivity of plants at home and abroad include anatomical method, "washing method", high-pressure flow meter method and evaporation flux method. Anatomical methods usually measure the diameter of xylem vessels, and the theoretical hydraulic conductivity is calculated by the Hagen-Poiseuille equation. The flush...

AI Technical Summary

Problems solved by technology

The above methods need to cut the stem section during the measurement process, resulting in the instantaneous loss of xylem tension and artificial embolization caused by air entry; at the same time, these methods cannot continuously monitor the change process of xylem hydraulic conductivity under field conditions, and the xylem hydraulic conductivity Continuous change is crucial for understanding plant responses to drought stress and more

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