METHOD FOR DETECTING ROOT RESUMPTION OF A PLANT
Patent Information
- Application Number
- FR2023010360
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2023-09-28
- Publication Date
- 2025-09-05
- Estimated Expiration
- 2043-09-28
AI Technical Summary
Existing methods for detecting root recovery in transplanted trees are unreliable and often destructive, failing to accurately assess the establishment of trees in urban environments due to soil compaction, unsuitable soils, and extreme weather conditions, leading to high post-transplant stress and mortality.
A method using soil water tension measurements from humidity sensors to determine root activity and recovery, involving threshold comparisons and digital data representation to model root dynamics, allowing real-time assessment of root recovery and establishment.
Enables accurate, non-destructive monitoring of root recovery, providing indicators for root activity, level, intensity, and efficiency, enhancing the chances of successful tree establishment in urban settings.
Smart Images
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Abstract
Description
Title of the invention: METHOD FOR DETECTING ROOT RESUMPTION OF A PLANT Technical field
[0001] The invention falls within the field of agronomy and relates more particularly to a method for detecting root recovery of a plant and a measuring station for implementing such a method for detecting root recovery. Prior art
[0002] It is now recognized that urban trees play a beneficial ecosystem role on the environment and on human health through the elimination of atmospheric pollutants, the storage and sequestration of carbon, protection against storms, the mitigation of the impacts of runoff water and flooding, the limitation of heat islands and even the improvement of cognitive development.
[0003] They are therefore considered among the best alternatives to adapt to the weather and climate changes experienced in our cities.
[0004] The first years of a tree's life, also called the recovery period, is generally defined as the period of time required for a tree to regrow its root system and be able to support aerial growth. In other words, recovery is a biological process during which the transplanted tree becomes permanently anchored in its new environment and from which it will be able to fulfill the expected ecosystem services. Indeed, newly transplanted trees suffer from "post-transplant stress" characterized by a modification of physiological functions and a decrease in growth. Roots that arise from seed seedlings develop naturally depending on soil conditions and other parameters such as climate or species, while the roots of transplanted trees are forced to acclimatize to their new environment.In most cases of tree transplants in urban areas, these are nursery trees that lose more than 70% of their root system, which triggers "post-transplant stress".
[0005] However, we are increasingly observing the decline and early mortality of trees in cities. Indeed, they are often subject to difficult growing conditions due to insufficient rooting space, soil compaction, unsuitable soils, high water stress, poor "post-transplant" management and biophysical factors such as climate and extreme weather conditions.
[0006] There is therefore an essential need to know the state of root recovery of the plant. to determine whether it has established itself correctly in its environment.
[0007] There are now methods that use physiological and morphological data of trees, such as the growth of shoots, leaves, trunk or stems.
[0008] Other methods are based on experiments conducted in vitro to understand the phenomena of root growth when others use imaging data capable of representing the architectural and functional structure of root development.
[0009] Root recovery can be partially deduced from observations at the aerial part of the plant by evaluating the growth dynamics of the plant crown over time and by correlation to determine root recovery. This indirect method is not sufficiently reliable to evaluate and optimize the recovery of the tree in its environment.
[0010] Root recovery can also be observed at the underground level thanks to observations by root excavation of the plant, allowing a precise idea of the level of root recovery to be obtained. This more direct method generally results in the death of the plant and is hampered by difficulties in accessing the road in urban environments. Statement of the invention
[0011] The objective of the invention is therefore to solve the aforementioned problems.
[0012] To this end, the invention relates to a method for detecting root regrowth of a plant, characterized in that it comprises the following steps carried out using a central unit and consisting of:
[0013] - record soil water tension measurements in the memory of the central unit over time carried out using at least one humidity sensor placed in the soil on an estimated path of growth of the plant roots,
[0014] - determine whether at least two successive soil water tension measurements are greater than a certain threshold water tension, and in return calculate a rate of change in soil water tension from said at least two identified soil water tensions,
[0015] - compare the rate of change in the calculated soil water tension with a threshold rate of change in soil water tension,
[0016] - create digital data representative of a root activity detection if the the rate of change of the calculated tensiometry is greater than the threshold rate for at least a first given period, and
[0017] - create digital data representative of the detection of a root recovery if during a second given period greater than the first given period, at at least two root activities are detected.
[0018] The idea behind the invention is to measure the soil moisture level around the roots of the plant to determine root activity in real time and then to model root dynamics of the plants representative of root recovery, ultimately making it possible to anticipate the chances of success of establishing the plant in its environment.
[0019] The method for measuring the root activity of the plant according to the invention can also have the following steps consisting of:
[0020] - calculate the number of root activities during the second given period, plus the number of root activities in said second given period being high and the more the plant shows a significant level of root recovery and in return create digital data representative of a level of root recovery;
[0021] - calculate the number of days during which the plant is in root activity during said second given period, the higher the number of days during said second given period, the more the plant shows a significant intensity of root recovery and in return create a numerical data representative of a certain intensity of root recovery;
[0022] - calculate a first average speed of evolution of the water tension of the soil during said first given period and in return create a digital data representative of an average intensity of root activity during said second given period Atl;
[0023] - calculate a second average speed of evolution of the soil water tension during said second given period and in return create a digital data representative of an average intensity of root activity during said second given period;
[0024] - define a certain root recovery efficiency, said recovery efficiency root recovery being determined by a correlation between the level of root recovery and the intensity of root recovery so that the higher the level of root recovery and the greater the intensity of root recovery during the second given period, the greater the efficiency of root recovery and in return create numerical data representative of a certain efficiency of root recovery during the second given period;
[0025] - calculate a duration during which the water tension of the soil measured by said humidity sensor is constant then compare said calculated duration with a constant soil water tension threshold duration beyond which it is considered that the plant is not in root activity, then create digital data representative of an absence of root activity if the calculated duration is greater than said threshold duration.
[0026] The invention also extends to a measuring station for detecting root recovery of a plant, comprising at least one sensor designed to measure water tensions in the soil and a central unit configured to implement the method according to the invention and a display screen. The central unit is designed to display said digital data representative of the detection of root recovery in several categories on the display screen.
[0027] The categories may also be displayed in the form of color coding on the display screen and / or icons. Brief description of the drawings
[0028] The present invention will be better understood and other advantages will appear on reading the detailed description of the embodiment taken as a non-limiting example and illustrated by the appended drawings, in which:
[0029] [Fig-1] - [Fig.l] is a diagram representing the different stages of the process according to the invention to detect root recovery;
[0030] [Fig.2] - [Fig.2] is a schematic representation of a measuring installation according to the invention using a measuring station according to the invention to implement the root recovery detection method according to the invention. Detailed description of the invention
[0031] The invention relates here to a method for detecting root recovery of a plant 1.
[0032] The term “plant” according to the invention extends to any type of plant intended to be planted in the ground in perennial or annual crops and capable of developing a root network, such as trees, shrubs, crops, lawns, etc. It is understood that the plant is relatively isolated from other plants at the time of transplantation (from 30 cm for annual plants up to 1 m for trees) so that their root systems are not or only slightly entangled.
[0033] The terms “root recovery” of a plant according to the invention represent a certain periodicity of root activity of the plant which corresponds to a state of implantation of the plant in its environment.
[0034] The terms "root activity" according to the invention represent a drying out of the soil attributed to the action of the roots of the plant at a given moment. In other words, a root recovery according to the invention corresponds to a certain dynamic of root activity.
[0035] The method for detecting root recovery according to the invention therefore comprises several steps carried out using a central unit 2 and at least one humidity sensor 3 placed in the soil 4 on an estimated path of growth of the roots 5 of the plant 1.
[0036] The central unit 2 is then configured to recover the soil water tension measurements taken over time by said at least one humidity sensor 3.
[0037] It will be understood that several humidity sensors 3 may be arranged on the estimated path of growth of the roots 5 of the plant 1, such as, for example, a first humidity sensor 3a arranged as close as possible to the roots in the root ball of the plant 1, a second humidity sensor 3b distant from the first humidity sensor 3a on a horizontal plane and a third humidity sensor 3c distant from the second humidity sensor 3b on a vertical plane.
[0038] Said at least one humidity sensor 3 according to the invention is here designed to measure a water content or a water tension, here called water tension. The conversion of the water content to the water tension and vice versa is possible thanks to a suitable pedotransfer function. In addition, the measured water content or water tension data are always converted into absolute values to facilitate reading of the data. For example, when the humidity sensors measure a water tension, the measured data are expressed in ohms then converted into mbar, for example between 0 and 2000 mbar, and finally converted into absolute values.
[0039] The soil water tension measurements may be recorded in a database 6, so that the database 6 includes for each humidity sensor 3 a plurality of water tension measurements taken over time. Indeed, the plant 1 which has just been transplanted only has roots 5 at the level of its root ball, roots 5 which will tend to develop horizontally then vertically relative to the root ball.
[0040] The root activity can therefore evolve at the level of the sensors 3 depending on their position relative to the root ball.
[0041] Also, in addition to the humidity data measured by the humidity sensors 3 in real time, the database 6 according to the invention comprises, for each plant 1 monitored, at least one or more of the following distinctive criteria: the type of species of the plant (for example its essence, the genus, etc.), the climatic region in which the plant is located, the texture of the root ball, the year of planting, the planting context (earth-stone mixture, open ground or planting pit) and the geographical coordinates of the plant.
[0042] The central unit 2 according to the invention can then be configured to determine whether at least two successive soil water tension measurements, taken from the same humidity sensor 3, are greater than a certain threshold water tension a.
[0043] The threshold water tension a according to the invention corresponds here to the minimum tensiometry value taken into account to be able to determine root activity. This means that below the threshold water tension a, no root activity can then be determined.
[0044] The central unit 2 is then configured to calculate in return a rate of change in the water tension of the soil at the level of each sensor from said at least two identified soil water tensions and to compare the rate of change of the calculated soil water tension with a threshold rate of change [3 of the soil water tension.
[0045] The threshold speed [3 of evolution of the water tension according to the invention corresponds here to the value of the minimum speed of evolution of water tension of the soil from which it is possible to determine a root activity.
[0046] The threshold speed [3] was determined in advance by carrying out an in situ analysis on a large number of plants (trees, shrubs, etc.). Plants planted simultaneously were dug up successively over several years to be able to observe the evolution of the roots.
[0047] The threshold speed [3 according to the invention will for example be between 0.1 and 10 mbar / hour depending on the choice of the different distinctive criteria listed above.
[0048] The threshold speed [3 of evolution of the water tension therefore corresponds to a certain speed of decrease of the humidity of the soil 4 above which the decrease of the humidity of the soil 4 is attributed to the presence and activity of roots 5. It can therefore be considered that a speed of decrease of the humidity of the soil 4 below the threshold speed [3 corresponds substantially to a low speed of drying of the soil 4, by evaporation for example.
[0049] It is understood that if several humidity sensors 3 are used, each sensor will use its own successive water tension measurements to calculate the rate of change of the water tension of the soil at said sensor. The central unit 2 will also be able to calculate the rate of change of the water tension of the soil at several sensors at different or identical times as required.
[0050] It is also understood that different threshold speeds [3 of evolution of the water tension can be used depending on the depth at which the humidity sensor is positioned, the type of soil, the type of plant monitored, etc.
[0051] The central unit 2 according to the invention will also be configured to create digital data representing a detection of root activity if the speed of evolution of the calculated tensiometry is greater than the threshold speed [3 during at least a first period Atl, then to create digital data representing the detection of a root recovery if during a second period At2 greater than the first period Atl, at least two root activities are detected.
[0052] The period Atl is defined in advance and can be entered into the configuration of the central unit 2. For example, the first duration Atl can be taken as a certain number of days, for example between 1 and 7 days, preferably 3 days.
[0053] The second period At2 will necessarily be greater than the first period Atl and could last, for example, several days, weeks, months or even several years. function of the plant to monitor, for example here 1 year for a fruit tree.
[0054] In addition to being able to detect root recovery of the plant, the method according to the invention also makes it possible to determine indicators providing additional information on root recovery.
[0055] Among these indicators, the method according to the invention makes it possible to characterize a certain level of root recovery, consisting of calculating, using the central unit 2, the number of root activities during the period At2. The central unit is then configured to create digital data representative of a certain level of root recovery so that the higher the number of root activities in said period At2, the more the plant 1 will have a significant level of root recovery. In other words, the higher the number of root activities in said period At2, the more the plant 1 will be well established in the soil 4.
[0056] Another indicator according to the invention corresponds to a certain intensity of root recovery calculated using the central unit 2 and corresponding to the number of days during which the plant 1 is in root activity during said second given period At2. The central unit 2 is then configured to create a digital data item representative of said intensity of root recovery so that the higher the number of days during said second given period At2, the greater the intensity of root recovery of the plant 1 will be.
[0057] The method according to the invention also makes it possible to produce an indicator corresponding to an average intensity of root activity during said first given period Atl. For this, the central unit is configured to calculate a first average speed Vml of evolution of the water tension of the soil 4 during said first given period Atl and then to create in return a digital data item representative of an average intensity of root activity during said second given period Atl.
[0058] Another indicator according to the invention may be determined by the central unit 2 and corresponds to an average intensity of root activity during said second given period At2. The central unit 2 will in this case be configured to calculate a second average speed Vm2 of evolution of the water tension of the soil during said second given period At2 then to create in return a digital data item representative of an average intensity of root activity during said second given period At2.
[0059] Another indicator according to the invention corresponds to a certain efficiency of root recovery. For this, the central unit 2 will be configured to correlate the level of root recovery with the intensity of root recovery so that the higher the level of root recovery and the greater the intensity of root recovery during the given period At2, the greater the efficiency of root recovery will be. The unit central 2 will in return produce digital data representative of said certain root recovery efficiency during the given period At2.
[0060] The central unit 2 according to the invention may also be configured to provide an indicator of absence of root activity. For this, the central unit 2 will be configured to calculate a duration At3 during which the water tension of the soil measured by said humidity sensor is constant, to compare said calculated duration At3 with a threshold duration y of constant water tension of the soil beyond which it is considered that the plant is not in root activity, and to create digital data representative of an absence of root activity if the calculated duration is greater than said threshold duration.
[0061] The implementation of the method according to the invention for the detection of root regrowth will comprise the following successive steps:
[0062] At a step 100, each humidity sensor 3 makes measurements of water tension in the soil 4 and feeds the database 6 in memory of the central unit.
[0063] At a step 200, the central unit 2 determines whether at least two successive soil water tension measurements 4 are greater than a certain threshold water tension (a), and calculates, at a step 300, in return a rate of change in the soil water tension from said at least two identified soil water tensions 4.
[0064] At a step 400, the central unit 2 compares the rate of change of the calculated soil water tension with a threshold rate of change [3 of the soil water tension.
[0065] At a step 500, the central unit creates digital data representing a detection of root activity if the speed of evolution of the calculated tensiometry is greater than the threshold speed (|3) during at least a first given period Atl.
[0066] And finally, at a step 600, the central unit creates digital data representing the detection of a root recovery if during a period At2 greater than the period Atl, at least two root activities are detected.
[0067] The invention also extends to a measuring station 7 designed to detect root recovery of a plant 1. The measuring station 7 according to the invention will comprise at least one humidity sensor 3 designed to measure water tensions of the soil 4, a display screen 8 and a central unit 2 configured to implement the method according to the invention and display said digital data representative of the detection of root recovery in several categories. A first category may for example represent a detection of root recovery, a second category may for example represent a level of root recovery, a third category may for example represent an intensity of root recovery, and a fourth category may represent a certain average intensity of root recovery.
[0068] Each category may include subcategories to represent the root recovery developments upward or downward.
[0069] Without restricting the scope of the invention, the categories may be displayed in the form of a color code on the display screen 8 and / or in the form of icons.
Claims
Claims
1. Method for detecting root regrowth of a plant (1), characterized in that it comprises the following steps carried out using a central unit (2) and consisting of: - recording (100) in the memory of the central unit measurements of soil water tension (4) over time carried out using at least one humidity sensor (3) arranged in the soil on an estimated path of growth of the roots (5) of the plant, - determining (200) whether at least two successive soil water tension measurements are greater than a certain threshold water tension (a), and calculating (300) in return a rate of change of the soil water tension from said at least two identified soil water tensions, - comparing (400) the calculated rate of change of the soil water tension with a threshold rate of change (|3) of the soil water tension,- create (500) a digital data item representing a detection of root activity if the rate of change of the calculated tensiometry is greater than the threshold rate (|3) during at least a first given period (Atl), and - create (600) a digital data item representing the detection of root recovery if during a second given period (At2) greater than the first period (Atl), at least two root activities are detected.,
2. Method for detecting root recovery of a plant according to claim 1, characterized in that it comprises a step consisting of calculating the number of root activities during the second given period and in that the higher the number of root activities in said second given period, the more the plant shows a significant level of root recovery and in that it comprises a step consisting of creating in return a digital data item representative of a level of root recovery.
3. Method for detecting root recovery of a plant according to claim 1, characterized in that it comprises a step consisting of calculating the number of days during which the plant is in root activity during said second given period and in that the higher the number of days during said second given period, the more the plant shows a significant intensity of root recovery and in that it includes a step consisting of creating in return a digital data representative of a certain intensity of root recovery.
4. Method for detecting root recovery of a plant according to any one of the preceding claims, characterized in that it comprises a step consisting of calculating a first average speed (Vml) of evolution of the water tension of the soil during said first given period and in creating in return a digital data item representative of an average intensity of root activity during said first given period.
5. Method for detecting root recovery of a plant according to any one of the preceding claims, characterized in that it comprises the step of calculating a second average speed (Vm2) of evolution of the water tension of the soil during said second given period and to create in return a digital data item representative of an average intensity of root activity during said second given period.
6. Method for detecting root recovery of a plant according to claims 4 and 5, characterized in that it comprises a step consisting of defining a certain efficiency of root recovery, said efficiency of root recovery being determined by a correlation between the level of root recovery and the intensity of root recovery so that the higher the level of root recovery and the greater the intensity of root recovery during the given period At2 and the greater the efficiency of root recovery and to create in return digital data representative of a certain efficiency of root recovery during the given period At2.
7. Method for detecting root recovery of a plant according to claim 1, characterized in that it comprises the steps of calculating a duration (At3) during which the water tension of the soil measured by said humidity sensor is constant, comparing said calculated duration with a threshold duration (y) of constant water tension of the soil beyond which it is considered that the plant is not in root activity, then creating digital data representative of an absence of root activity if the calculated duration is greater than said threshold duration.
8. Measuring station (7) designed to detect root recovery of a plant, comprising at least one sensor designed to measure soil water tensions and a central unit configured to implement the method according to any one of the preceding claims, characterized in that the station comprises a display screen (8) and in that the central unit is designed to display said digital data representative of the detection of root recovery in several categories on the display screen.
9. Measuring station according to claim 8, characterized in that the categories are displayed in the form of color code on the display screen and / or icons.