Plant perception mechanism and near-sensing physical two-way synchronous detection platform and use method

Abstract

The application provides a plant perception mechanism and a bidirectional synchronous detection platform for near-sensing physics and a use method. The functional units include a growth chamber system, an illumination system, a radiation detection system, a point cloud detection system and an angle control system. The angle control system is used for controlling the detection angles of the illumination system, the radiation measurement system and the point cloud scanning system respectively, so as to support high-precision multi-angle measurement of light changes, reflection attribute changes and corresponding morphological adjustment of the target plant. Therefore, the application can not only deduce the perception (phototropism and gravitropism) mechanism of the plant from the combined information of the light changes and the corresponding morphological adjustment, but also analyze the near-sensing physics of the plant from the combined information of the light changes and the reflection attribute changes by combining the morphological records at the corresponding moment. Based on the corresponding specific implementation method, the platform can realize bidirectional synchronous detection of the plant perception mechanism and the near-sensing physics.

Description

TECHNICAL FIELD

[0001] The present application relates to a plant perception mechanism and near-sensing physical bidirectional synchronous detection platform and use method, and relates to the fields of plant remote sensing and plant perception. BACKGROUND

[0002] Plant near-sensing physics: the leaf surface reflection of plants can accurately quantify the biochemical parameters of plant leaves, and thus reflect the growth and nutritional status of plants. It has been widely used in the evaluation of carbon cycles in various terrestrial ecosystems, such as precision agriculture and forestry, and has great significance for responding to and achieving the "double carbon" goal. In the laboratory, leaves are mostly cut from plants and immediately laid flat on measuring instruments for observation. The technology of using integrating spheres and DHRF to obtain leaf surface reflection has been quite mature, and high-precision directional-hemispherical reflectance models such as the PROSPECT-PRO model have been derived. In recent years, due to the emergence of leaf clamps and close-range imaging spectrometers, BRF is more suitable than DHRF for inverting leaf chlorophyll content, and BRF is gradually applied to obtain plant leaf surface reflection. However, under the same conditions, the BRF of the same leaf is slightly larger than the DHRF in the entire visible region, because BRF contains the specular reflection component of the leaf, while the measurement of DHRF is often in an integrating sphere, and the specular reflection component is averaged and weakened in the entire hemispherical space. Therefore, in DHRF, when the angle of the incident light relative to the normal of the leaf is small, the specular reflection component can be ignored, resulting in that the value of DHRF often depends only on the diffuse reflection caused by the internal biochemical components of the leaf. The specular reflection of vegetation leaves is itself an interaction between leaf structure and photons, mainly caused by the local or concave or convex structures of the wax layer and leaf veins on the leaf surface, which makes the leaf have a specular reflection property to solar radiation. If the influence of specular reflection is ignored, the model based on DHRF will be directly used for chlorophyll inversion based on BRF, and studies have shown that the chlorophyll content will be severely underestimated. Although some vegetation indices, such as normalized-difference (ND), double-differenceratios (DD) and red edge positions (REPs), are not sensitive to specular reflection, they can be used for DHRF spectral inversion of plant biochemical component content and BRF spectral inversion of plant biochemical component content, but the actual accuracy of the latter is still slightly lower than that of DHRF spectral inversion results, and the model effect depends on the training data set; similarly, the existing BRF-based model can be used to describe the angular reflection characteristics of the leaf, but it focuses more on the inversion of leaf structure parameters and does not consider the influence of internal biochemical components of the leaf.

[0003] Plant perception mechanism: The biggest factor affecting plant growth is the gravity of the earth and the light-induced changes in plant internal hormones and cell structure. In recent decades, researchers' interest in the factors affecting plant growth has focused on the cellular and molecular mechanisms of plant perception of environmental factors and how plants transmit the perceived signals to hormone gradients, particularly auxin gradients, to stimulate asymmetric growth. For the gravitropism of plants, the phenomenon of apical dominance can be explained. Generally, the top of the main stem grows quickly, and the lateral buds grow slowly or are dormant. This phenomenon, in which the top of the main stem grows faster and prevents the emergence of lateral buds or inhibits the growth of lateral branches, is called apical dominance. This phenomenon is common in the plant kingdom, but varies greatly among different plants. Currently, the cause of apical dominance is mostly attributed to the auxin-induced inhibition theory triggered by the top bud and gravity. The auxin-induced inhibition theory has some experimental basis: after removing the top, the lateral buds can grow quickly, and if the cut is coated with lanolin containing auxin, the lateral buds will also grow slowly, that is, the exogenous auxin can replace the inhibition of the lateral buds by the top. However, some people have found that in plants such as Lupinus, the auxin content in the inhibited lateral buds is higher than the optimal concentration required for lateral bud growth. Moreover, the application of cytokinin to the inhibited lateral buds allows the lateral buds to grow (i.e., apical dominance is removed), so it is believed that the reason for the inhibition of lateral buds is that they do not have enough cytokinin. Cytokinin is synthesized in the roots, and the effect of auxin produced by the top bud may control the transport of cytokinin. Since the auxin of the top bud is transported to the lateral buds through polar transport, the concentration of auxin in the top bud is lower than that in the lateral buds, becoming a sink for input material and getting cytokinin preferentially. The high concentration of auxin in the lateral buds prevents them from getting enough cytokinin, and their growth is inhibited. Therefore, due to the effect of gravity, a large amount of auxin is transported uniformly downward from the top of the main stem to the lateral branches, leading to the nearly vertical upward growth of the main stem of woody plants, while the growth of the lateral buds is inhibited. The phototropism of plants is the growth activity induced by the response of plant organs to the stimulation of light incident in a certain direction. Under normal circumstances, the phototropism of plants is a very slow growth process, and some plants can change the posture of their leaves to chase the daily changes in sunlight in a relatively short period of time. The phototropism of plants is because the auxin on the shaded side of the main stem is more and grows faster, while the auxin on the light side is less and grows slower, so the top of the stem grows towards the light source. Plants growing in the wild and receiving uniform light, the stem of which receives the same amount of sunlight, has a uniform distribution of auxin, and the stem grows straight. Plants growing under uneven light, the light side of which receives stronger light, and the auxin on the light side is transferred to the shaded side, causing the main stem to bend towards the light source. Therefore, the phototropic bending of plants is related to the uneven distribution of auxin on the light side and the shaded side. Unidirectional light causes auxin to move to the shaded side, resulting in faster growth on the shaded side than on the light side, and exhibiting phototropic bending.The reason for the auxin moving to the back light side may be related to the potential difference generated at different parts of the organ tip caused by light. The light side is negatively charged, the back light side is positively charged, and the weakly acidic auxin anion is attracted to the back side by the positive charge, resulting in the migration of auxin inside the main stem.

[0004] In recent years, with the continuous development of remote sensing technology, a series of high-precision observation capabilities of laser radar, photometer and other remote sensing instruments have emerged, but the perception mechanism of plant growth and its near-sensing physics have not been comprehensively studied with new technical means. Therefore, fully utilizing the point cloud data and photometric measurement data to jointly carry out the bidirectional synchronous detection of plant perception mechanism and near-sensing physics can solve the bottleneck problem that is difficult to solve in the previous plant physiology research, and start a new era of botanical research. SUMMARY

[0005] The present application aims to at least solve one of the technical problems existing in the prior art. To this end, in view of the above problems, the purpose of the present application is to provide a bidirectional synchronous detection platform and use method for plant perception mechanism and near-sensing physics, which can accurately obtain plant morphological structure attributes, and can quantitatively monitor plants in their original posture and growth state, avoiding the traditional mode of destroying plants to obtain plant biochemical properties.

[0006] In order to achieve the above application purpose, the technical scheme provided by the present application is:

[0007] In a first aspect, the present application provides a bidirectional synchronous detection platform for plant perception mechanism and near-sensing physics, which comprises a growth chamber system, wherein the growth chamber system is provided with a lighting system, a radiation detection system, a point cloud detection system, an angle control system and a support platform;

[0008] The growth chamber system is used to provide constant temperature and humidity for plants and effectively avoid the influence of external radiation on plant growth;

[0009] The lighting system is used to provide plants with incident light sources close to the solar spectrum and isotropic parallel light sources;

[0010] The radiation detection system is used to obtain photosynthetic radiation PAR received by the plant and measure the reflected radiation value of the plant;

[0011] The point cloud detection system is used to observe the shape change and growth of the plant, and based on the point cloud data of the plant, the reflectivity of the plant point cloud is obtained to study the structure characteristics and biochemical characteristics of the plant;

[0012] The angle control system is used to control the angles of the lighting system, the radiation detection system and the point cloud detection system respectively, and to explore the growth of the plant under different incident angles;

[0013] The support platform is used to provide physical support for the lighting system, the radiation detection system and the point cloud detection system.

[0014] Further, the growth chamber system adopts a light-tight growth chamber, a light-shielding curtain is installed in the growth chamber, which can provide a relatively closed space and reduce the interference of natural light sources; the walls of the growth chamber are covered with black cloth, which can reduce the error caused by the reflection and multiple scattering of light on the walls.

[0015] Further, the support platform includes a support base plate, a base for placing plants is arranged on the support base plate, the base can carry plants and at the same time drive the plants to rotate at different angles, so that the plants rotate from a vertical state to an inclined state at different angles, a vertical support rod is arranged on one side of the support base plate, and a horizontal support rod is arranged on the upper portion of the vertical support rod.

[0016] Further, the lighting system includes neon tubes, searchlights and a support plate.

[0017] At least one neon tube is arranged on the vertical support rod through the support plate as a plant growth light source, each neon tube is arranged in a mode that can be independently turned on to ensure that the irradiation light only comes from the side below the plants, which facilitates the differentiation of the gravitropism and phototropism of trees, and the support plate is a dark plate.

[0018] The searchlight is used to emit isotropic parallel light to irradiate the leaves, the searchlight adopts an isotropic light source, and the light spectrum emitted by the isotropic light source is close to the solar spectrum.

[0019] Further, the radiation detection system includes a luminometer and a spectrometer.

[0020] The luminometer is used to measure the spectrum of the neon tubes with different powers and the light flux and the radiation flux of blue light as the main radiation of photosynthesis reaching the stems of saplings at different inclination angles.

[0021] The spectrometer is used to measure the reflected radiation of the leaves observed at different angles to calculate the directional reflectivity and BRDF of the leaves.

[0022] Further, the point cloud detection system adopts a laser radar, which is used to scan the plant morphology to obtain plant point clouds and obtain multi-band reflectivity of the point clouds, which is used to deeply understand the influence of the internal structure mechanism and biochemical components of plants on the tropotropism growth.

[0023] Further, the angle control system adopts a ring device, the ring device comprises a first rotatable and slidable ring-shaped mechanical arm, a second ring-shaped mechanical arm and a ring-shaped track, ends of the first ring-shaped mechanical arm, the second ring-shaped mechanical arm and the ring-shaped track are movably connected with the transverse support rod, wherein:

[0024] The searchlight is arranged on the first ring-shaped mechanical arm, which can not only ensure that the searchlight appears at different azimuth angles of the plant, but also can present different zenith angles at different azimuth angles, which is more conducive to determining the directional reflection characteristics of the plant.

[0025] The radiation receiving probe of the spectrometer is arranged on the second ring-shaped mechanical arm, which ensures that the reflected radiation of the plant leaves at different azimuth angles and different zenith angles is received, and the BRDF characteristics of the plant are obtained.

[0026] The photometer is arranged on the second ring-shaped mechanical arm, which can measure the light flux reaching the stem of the sapling at different inclination angles.

[0027] The laser radar is placed on the ring-shaped track, which can completely scan the morphological characteristics of the entire plant.

[0028] Further, the reference plate is arranged on the support platform, the angle of the reference plate can be adjusted, which is used for distance correction and radiation intensity correction of the photometer and the laser radar, and the error existing in the use process is corrected.

[0029] Further, the BRDF characteristics of the leaves calculated according to the PROSPECULAR model are used to estimate the biochemical composition content and the surface roughness of the leaves without contact. Since BRDF is the ratio of two minima, it cannot be directly obtained. First, the BRF of the leaves is calculated:

[0030] The relationship between BRDF and BRF is as follows:

[0031]

[0032] Wherein, is the BRDF of the Lambertian surface;

[0033]

[0034] Wherein, dL leaf and dL reference are the leaf radiance and the reference plate radiance measured at the same azimuth angle, respectively, ρ λ is the reflectivity of the reference plate at the wavelength.

[0035] In a second aspect, the application also provides a method for using the bidirectional synchronous detection platform of plant perception mechanism and near-sensing physics, comprising:

[0036] The photometer directly measures the effective photosynthesis radiation received by the plant under different powers and different incident angles of the neon lamp tube, and obtains the PAR and the radiation flux of the blue light as photosynthesis based on the integral of the tilt angle and the lamp tube power;

[0037] The laser radar obtains the plant point cloud, observes the change of the plant growth caused by the interaction of the phototropism and the gravitropism of the plant under the dual influence of gravity and light, obtains the tilt angle of the plant leaf relative to the incident light source, and obtains the multi-band reflectivity data based on the scanned point cloud, studies the response of the plant reflectivity characteristics to different light sources, and determines the relationship between the plant structure parameters and biochemical component content related to the plant reflectivity characteristics and the plant tropism growth based on the point cloud reflectivity data.

[0038] The directional reflectivity characteristics of the leaf under different azimuth angles are measured by the searchlight and the spectrometer at different angles, the ecological properties and biochemical component content of the leaf are reflected, and the relationship between the biochemical state and the growth condition of the whole plant is reflected, so that the quantitative research on the biochemical parameters of the whole plant is realized.

[0039] The application has the following characteristics due to the above technical solutions:

[0040] 1、The platform of the application integrates the laser radar and the photometer, on the one hand, the laser point cloud data obtained based on the laser radar improves the error problem caused by the low-precision estimation measurement or actual contact measurement of the plant shape change in the traditional plant perception mechanism research, on the other hand, the multi-dimensional plant reflectivity data are used to contactlessly obtain the internal structure information and the plant biochemical component content, and the reflectivity data reflecting the real-time internal structure change and the biochemical component content change are creatively linked to the plant growth perception mechanism, so that the single-dimensional problem in the previous plant perception mechanism research is solved.

[0041] 2、The application does not avoid the specular reflection component of the plant leaf surface reflection in the traditional quantitative remote sensing, but uses multi-angle observation of the plant leaf reflection, simultaneously considers the specular reflection component and the diffuse reflection component of the plant leaf reflection, uses the PROSPECULAR model to separate the leaf specular reflection and the diffuse reflection, and in the case of allowing the existence of the specular reflection, can simultaneously inverse the leaf surface structure parameters and the internal biochemical component content, and further realizes the quantitative research on the biochemical parameters of the whole plant.

[0042] 3、Traditional quantitative remote sensing research of single plant often carried out on the single leaf of the plant, which needs to be destructively removed from the plant and quickly laid flat on the measuring instrument, changing its original structure, and then measuring its reflectivity or biochemical component content, and then obtaining the health status, growth status and other target information of the whole plant, which cannot completely reflect the posture, structure and biochemical component content of the plant in the original state. The present application sets a laser radar and a spectrometer capable of multi-angle observation, which can not only accurately obtain the plant morphological structure attributes, but also can quantitatively monitor the plant in the original posture and growth state, avoiding the traditional means of destroying the plant form to obtain the biochemical properties of the plant. The present application also creatively couples the plant growth characteristics (phototropism and gravitropism) monitoring with multi-angle remote sensing observation, and further explores the relationship between the biochemical component content of plant leaves, leaf structure parameters and growth trend.

[0043] In summary, the present application can be widely applied in plant mechanism research. BRIEF DESCRIPTION OF DRAWINGS

[0044] Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The accompanying drawings are included to provide a description of the preferred embodiments and are not intended to limit the scope of the present application. Throughout the drawings, the same reference designates the same elements. In the drawings:

[0045] Figure 1 The principle diagram of the two-way synchronous detection platform of plant perception mechanism and proximal sensing physics of the embodiment of the present application;

[0046] Figure 2 The structural diagram of the two-way synchronous detection platform of plant perception mechanism and proximal sensing physics of the embodiment of the present application;

[0047] Figure 3 The flow chart of data acquisition and data processing of the two-way synchronous detection platform of plant perception mechanism and proximal sensing physics of the embodiment of the present application. DETAILED DESCRIPTION

[0048] It is to be understood that the terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. The terms "comprises", "comprising", "includes", "including" and "has" are inclusive and therefore specify the presence of stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof. The method steps, processes, and operations described herein are not to be construed as necessarily requiring their performance in the particular order

[0049] Although the terms first, second, third, etc. can be used herein to describe various elements, components, regions, layers and / or sections, these elements, components, regions, layers and / or sections should not be limited by these terms. These terms can be only used to distinguish one element, component, region, layer or section from another region, layer or section. Terms such as "first", "second", and other numerical terms when used herein do not imply a sequence or order unless clearly indicated by the context. Thus, a first element, component, region, layer or section discussed below could be termed a second element, component, region, layer or section without departing from the teachings of the example embodiments.

[0050] Spatially relative terms, such as "inner", "outer", "beneath", "below", "lower", "above", "upper", and the like, can be used herein for ease of description to describe one element or feature's relationship to another element(s) or feature(s) as illustrated in the figures. The spatially relative terms are intended to encompass different orientations of the device in use or operation in addition to the orientations depicted in the figures.

[0051] The application provides a plant perception mechanism and near-sensing physical two-way synchronous detection platform and a use method, and relates to the technical field of plant perception mechanism and near-sensing physical two-way synchronous detection platform.

[0052] Exemplary embodiments of the present application will be described in greater detail below, with reference to the accompanying drawings. While exemplary embodiments of the present application are shown in the drawings, it is understood that the present application can be embodied in various forms without being limited by the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the application to those skilled in the art.

[0053] Embodiment one: as shown in the figure, the embodiment provides a plant perception mechanism and near-sensing physical two-way synchronous detection platform, which comprises a growth chamber system 1, a lighting system 2, a radiation detection system 3, a point cloud detection system 4, an angle control system 5 and a support platform 6. Figure 1

[0054] The growth chamber system 1 is used for providing constant temperature and humidity for plants, effectively avoiding the influence of external radiation (mainly natural sunlight) on plant growth and reducing multiple scattering in the chamber.

[0055] The lighting system 2 is used for providing incident light sources close to the solar spectrum and isotropic parallel light sources for plants.

[0056] The radiation detection system 3 is used for acquiring photosynthetically active radiation (PAR) received by plants and measuring the radiation value reflected by plants. ​

[0057] The point cloud detection system 4 is used to observe the shape change and growth of the plant, and is based on the point cloud data of the plant to obtain the reflectivity of the plant point cloud, study the structural characteristics and biochemical characteristics of the plant.

[0058] The angle control system 5 is used to control the angles of the lighting system 2, the radiation detection system 3 and the point cloud detection system 4 respectively, and to explore the growth of the plant under different incident angles.

[0059] The support platform 6 is used to provide physical support for the lighting system 2, the radiation detection system 3 and the point cloud detection system 4.

[0060] In a preferred embodiment of the present application, the growth chamber system 1 can adopt a light-tight growth chamber, and the lighting system 2, the radiation detection system 3, the point cloud detection system 4 and the angle control system 5 are arranged in the growth chamber.

[0061] Further, a light-blocking curtain is installed in the growth chamber, which can provide a relatively closed space and reduce the interference of natural light sources.

[0062] Further, the walls of the growth chamber are covered with black cloth, which can reduce the error caused by the reflection and multiple scattering of light on the walls, which causes the non-phototropic side of the plant to also be illuminated.

[0063] Further, the temperature and humidity of the growth chamber need to be fully controlled to ensure that a constant environment can be provided. The specific implementation process can be controlled as needed, for example: the humidity control of the growth chamber is mainly based on the humidity sensor to monitor the humidity of the growth chamber. The humidifier and dehumidifier can adjust the working intensity according to the current humidity level. The humidity sensor can be connected to a control system, and the humidifier or dehumidifier can be automatically started or stopped through the control system. The temperature control of the growth chamber mainly depends on the air conditioning system and the ventilation system. The air conditioning system sets a constant temperature range, and the best temperature for plant growth is usually between 18℃ and 25℃. At the same time, the ventilation system is installed to ensure air circulation and prevent the indoor temperature from being too high. In addition, in cold seasons, a heater can be used in the growth chamber to maintain the room temperature. The heater is provided with a temperature control device to avoid excessive high or low temperature.

[0064] In a preferred embodiment of the present application, as shown in Figure 2As shown, the support platform 6 comprises a support base plate 61, and a base 62 for placing plants is arranged on the support base plate 61, the base 62 can carry plants and simultaneously drive the plants to rotate, so that the plants rotate from a vertical state to an inclined state at different angles. A vertical support rod 63 is arranged on one side of the support base plate 61, and a horizontal support rod 64 is arranged at the upper portion of the vertical support rod 63. The purpose of installing the plants on the base 62 capable of being inclined at different angles is to explore the individual influence of gravitropism on the growth of plants and the comprehensive influence of gravitropism and phototropism on the growth of plants.

[0065] Further, multiple support platforms 6 can be installed simultaneously according to needs. Since the observation of the phototropism and gravitropism of plant growth only relies on one sample, there is a large accidental error, therefore, multiple platforms and multiple plants of the same kind can be arranged in the growth chamber for observation of the growth of plants, so as to reduce the influence of accidental errors, and if multiple similar growth chamber systems can be used simultaneously, then multiple groups of plants can be experimented simultaneously, which can be set according to needs, and details are not described herein.

[0066] In a preferred embodiment of the present application, the lighting system 2 comprises a neon lamp tube 21, a support plate 22 and a searchlight 23. In this embodiment, the neon lamp tube 21 is a ring-shaped neon lamp tube 21, and this is an example and is not limited thereto.

[0067] The vertical support rod 63 is provided with a ring-shaped neon lamp tube 21 as a plant growth light source through the support plate 22. In this embodiment, two ring-shaped neon lamp tubes 21 are vertically arranged on the support plate 22, and this is an example and is not limited thereto, and can be set according to actual needs. It should be noted that different power ring-shaped neon lamp tubes 21 arranged in a vertical line are used to simulate sunlight of different intensities in this embodiment, and each ring-shaped neon lamp tube 21 is arranged in a mode capable of being independently turned on to ensure that the light only comes from the side below the plants, so that the gravitropism (vertical upward growth of tree seedlings) and phototropism (movement of tree seedlings towards the light source) of trees can be more accurately distinguished.

[0068] Further, the ring-shaped neon lamp tube 21 is used to provide an incident light source close to the solar spectrum to the plants. According to needs, the ring-shaped neon lamp tube 21 can adopt different lighting powers, and the lighting power of the ring-shaped neon lamp tube 21 can be controlled by replacing the ring-shaped neon lamp tube, and 55W, 40W and 22W can be selected. If a ring-shaped neon lamp tube with a light power of 15W is needed, a filter can be arranged in front of the 22W ring-shaped neon lamp tube to obtain the filter, and the filter is detachable, which is designed to provide other power light sources in addition to fixed power.

[0069] Further, the model of the ring-shaped neon lamp tube 21 can be OSRAM FC 865, and this is an example and is not limited thereto.

[0070] Further, the support plate 22 is used for supporting and fixing the annular neon lamp 21, and the support plate 22 can be selected as a dark plate, because a white plate can cause a large degree of reflected light to reach the growth chamber wall, and finally cause multiple scattering to cause the overall growth chamber to be too bright, and cause the plants to receive light sources that are not from a single side of an anisotropic light source, and the dark plate can greatly absorb the radiant energy emitted by the light source to the support plate.

[0071] Further, the searchlight 23 is used for emitting a parallel light of isotropic light to irradiate the leaves, and the searchlight 23 is selected as an isotropic light source, and the selection of the isotropic light source is preferably close to the solar spectrum, because the solar incident light reaching the ground plants is an isotropic light source, and the selection of the isotropic light source close to the solar spectrum in the growth chamber is to achieve simulation in the growth chamber. The searchlight 23 is generally provided as a plurality of circular lamp tubes arranged in parallel, and the function is mainly to supply plant growth, and the searchlight 23 is also preferably close to the solar spectrum, and the light source generally has a small caliber, so that a small scattering loss can be ensured, and the light source is used to obtain the reflectivity data of the plants. In order to be able to irradiate the leaves with parallel incident light, it is ensured that the incident light source is unidirectional, which facilitates the calculation of the BRF of the leaves, and then the directional-directional reflectance characteristics of the leaves are obtained.

[0072] In a preferred embodiment of the present application, the radiation detection system 3 comprises a photometer 31 and a spectrometer 32.

[0073] The photometer 31 is used for measuring the spectrum of the annular neon lamp 21 with different powers, and the photometer 31 measures the light flux reaching the tree trunk at different inclination angles, so that the photosynthetic active radiation (PAR) can be calculated. The photometer 31 is mainly used to measure the spectrum of the annular neon lamp 21 with different powers (15W, 22W, 40W, 55W), and to obtain the PAR and the radiation flux of the blue light as the main radiation of photosynthesis based on the integral of the inclination angle and the lamp power.

[0074] The spectrometer 32 is used for measuring the plant reflected radiation value, and the spectrometer 32 is used to measure the leaf reflected radiation observed at different angles, and the directional-directional reflectivity and the BRDF (bidirectional reflectance distribution function) of the leaves can be calculated, wherein the directional-directional reflectivity represents that the solid angles of the incident radiation and the reflected radiation tend to 0, and is generally defined as the ratio between the reflected radiation and the incident radiation; the BRDF is a basic parameter for describing the spatial distribution of the reflection characteristics of the object surface, and mainly describes the characteristics that the reflectivity of the object changes with the incident direction and the reflection direction, and the size depends on the spectral characteristics, spatial structure, incident, and reflection direction variables of the object itself.

[0075] In a preferred embodiment of the present application, the point cloud detection system 4 adopts a laser radar 41 (LiDAR). The laser radar 41 is used to scan the plant morphology and obtain the point cloud, and obtain the multi-band reflectivity of the point cloud. On the one hand, the laser radar is used to observe the diameter growth change of the plant stem, and the tropotropism growth of the plant is observed by observing the morphological change of the plant; on the other hand, the laser radar is used to obtain the multi-band reflectivity of the point cloud. The laser radar used in the present application can not only obtain the three-dimensional morphology of the plant by scanning the target, but also each point cloud after scanning has the multi-band reflectivity of the target in the visible-near infrared range, so that the influence of the internal structure mechanism and biochemical composition of the plant on the tropotropism growth can be deeply understood.

[0076] Further, as shown in Figure 3 After the laser radar 41 obtains the plant morphology data, the data quality needs to be processed through point cloud registration, point cloud repair and thinning, point cloud denoising, point cloud feature extraction, point cloud segmentation, point cloud classification, and the like, so that the obtained plant point cloud can be put into use. For example, before the tropotropism growth is monitored for two consecutive weeks, the laser radar records the daily average diameter growth rate of the plant stem 10 cm away from the base and the shape fitting curve formed by fitting the point cloud every 2-3 days.

[0077] In a preferred embodiment of the present application, a reference plate is further included, which can be arranged on the support platform 6, and the specific position is not limited, as long as it does not affect the plant to receive light. The reference plate can be adjusted when fixed to adjust the radiation angle, and is used to correct the distance and radiation intensity of the two data of the luminometer 31 and the laser radar 41, and correct the errors existing in the use process of the instrument.

[0078] In a preferred embodiment of the present application, the angle control system 5 includes a ring-shaped device capable of controlling different angles of the searchlight 23, the luminometer 31, the spectrometer 32 and the laser radar 41. The ring-shaped device includes a first ring-shaped mechanical arm 51, a ring-shaped track 52 and a second ring-shaped mechanical arm 53, and the ends of the first ring-shaped mechanical arm 51, the ring-shaped track 52 and the second ring-shaped mechanical arm 53 are movably connected with the transverse support rod 64. The ring-shaped device surrounds all the systems except the growth chamber system, so that all the morphological structures and posture changes of the plant can be completely scanned.

[0079] Further, the searchlight 23 is arranged on the rotatable and slidable first ring-shaped mechanical arm 51, which can not only ensure that the searchlight appears at different azimuth angles of the plant, but also can present different zenith angles at different azimuth angles, which is more conducive to determining the directional reflection characteristics of the plant.

[0080] Further, the luminometer 31 is arranged on the rotatable and slidable second ring-shaped mechanical arm 53, and the luminometer 31 mainly obtains radiation through a probe.

[0081] Further, the radiation receiving probe of the spectrometer 32 is arranged on the rotatable and slidable second annular mechanical arm 53, so as to receive the reflected radiation of the plant leaves at different azimuth angles and different zenith angles, and facilitate the acquisition of the BRDF characteristics of the plant.

[0082] Further, the laser radar 41 is arranged on the rotatable and slidable annular track 52, and can completely scan the morphological characteristics of the entire plant.

[0083] In a preferred embodiment of the present application, for the common model PROSPECT model used to simulate the reflectivity of the leaves, the input condition of the model forward is the biochemical component content of the leaves, and the present application uses the non-contact measurement of the leaves, so that the inversion is only performed in the reverse direction. For the inversion of the PROSPECT model, the reflectivity and the transmissivity of the leaves are used to inversely deduce the biochemical component content of the leaves, but the input reflectivity is the directional-hemispherical reflectivity, that is, the reflectivity measurement of a single light source on the leaves in the integrating sphere, and the reflectivity in the present application is the directional-directional reflectivity. If the specular reflection component is ignored, the biochemical component content of the leaves will be seriously misestimated. The prior art proposes a PROSPECULAR model, which couples the PROSPECT model with a specular reflection function, and divides the reflected radiation into the specular reflection component and the diffuse reflection component, so as to not only evaluate the leaf surface roughness causing the specular reflection of the leaves, but also evaluate the biochemical component content of the leaves according to the diffuse reflection component, and better adapt to the present application. Therefore, the present application discards the idealized PROSPECT model in the traditional research, and uses the more accurate PROSPECULAR model to simulate the reflectivity of the leaves, so as to reflect the structure and the biochemical component of the plant leaves. The present application can obtain the morphological and attitude information of the leaves. The morphological information of the leaves mainly refers to the shape, size (width, thickness, etc.), leaf structure, veins, surface texture, etc. of the leaves. The attitude information of the leaves mainly refers to the inclination angle of the leaves relative to the normal line, the arrangement mode, the twist or bending, the orientation of the leaves, etc. Therefore, the azimuth angle of the leaves receiving the probe lamp radiation can be constructed, and the biochemical component content and the leaf surface roughness of the leaves can be non-contact estimated according to the BRDF characteristics of the leaves calculated by the PROSPECULAR model. It should be noted that the BRDF is the ratio of two very small values, so it cannot be directly obtained, and the BRF of the leaves needs to be calculated first.

[0084] The relationship between the BRDF and the BRF is as follows:

[0085]

[0086] wherein, is the BRDF of the Lambertian surface.

[0087] The final result often depends on the actual measurement, i.e. BRF:

[0088]

[0089] where dL leaf and dL reference are the leaf radiance and the reference plate radiance measured at the same azimuth, which requires that the reference plate in the present application can also rotate at a certain angle; p λ is the reflectivity of the reference plate at the waveband.

[0090] In summary, in monitoring plant growth and exploring plant perception mechanism, the plant perception mechanism and proximate physical two-way synchronous detection platform in the present application is set in a growth chamber environment with stable temperature and humidity, the incident radiation is emitted by the neon lamp installed on the dark plate, transmitted through a short distance of air to the plant and the photometer, and the photometer can directly measure the photosynthesis radiation (PAR) received by the plant. Every 2-3 days, the growth condition of the plant is scanned by the laser radar, and the point cloud obtained by scanning can realize non-contact accurate measurement of the stem diameter of the plant and the morphological changes caused by tropic growth.

[0091] Embodiment two: the use method of the plant perception mechanism and proximate physical two-way synchronous detection platform provided by the present application, comprising:

[0092] S1, directly measuring the effective photosynthesis radiation received by the plant under different powers and different incident angles of the annular neon lamp 21 by the photometer 31, and integrating the PAR and the radiation flux of blue light as the main radiation of photosynthesis based on the tilt angle and the lamp power.

[0093] S2, observing the change of the plant growth caused by the interaction of the phototropism and the gravitropism of the plant under the double influence of gravity and light by the plant point cloud obtained by the laser radar 41, and simultaneously obtaining the tilt angle of the plant leaves relative to the incident light source; secondly, the point cloud obtained by the laser radar 41 in the present application can obtain multi-waveband reflectivity data, which can not only be compared with the plant reflectivity factor obtained by the ordinary light source to study the response of the plant reflectivity characteristics to different light source types, but also can explore the relationship between the plant structure parameters and biochemical component content related to the plant reflectivity characteristics and the tropic growth of the plant based on the point cloud reflectivity data.

[0094] Further, the spectral curve of the reflectivity of the plant leaf at 400nm-2500nm can reflect the health condition, structural attribute and biochemical component content, and a large number of leaf reflectivity models can be used to obtain the attribute values according to the measured reflectivity, and the platform can continuously obtain the structural parameters and biochemical component content of the plant at different growth moments according to the continuously measured reflectivity, and establish the relationship between the changes and the tropistic growth of the plant.

[0095] S3, the directional reflection characteristics of the leaf at different azimuth angles measured by the searchlight 23 and the spectrometer 32 at different angles can reflect the ecological attribute and biochemical component content of the leaf to a certain extent, and further reflect the relationship between the biochemical state and the growth condition of the whole plant.

[0096] Further, since the leaf specular radiation observed by the application at multiple angles does not contain the biochemical component information inside the leaf, according to the Fresnel formula, this part of radiation is partially polarized light, so the application can also be used for polarization remote sensing research, which will help to deepen the method and rule of vegetation remote sensing polarization observation, for example, how the leaf inclination angle distribution function affects the polarization reflection characteristics of vegetation, and further affects the vegetation biochemical parameter inversion. At the same time, the plant multi-angle polarization data obtained by the application can be further analyzed for the polarization reflection and filtering characteristics of vegetation at different observation scales, and if it can be effectively considered in the quantitative remote sensing model, it can be used to explore the hot spot effect of vegetation remote sensing and the absorption, single and multiple scattering intensity characteristics of vegetation to different wave bands of electromagnetic waves, improve the accuracy of the existing polarization reflectivity model, and further extend and develop the known polarization effect of light in the vegetation canopy, which will help to improve the accuracy of the existing canopy biochemical parameter inversion model of trees, forests and other trees, and further better understand the global forest system carbon sink and carbon cycle, and do a good job in carbon peak and carbon neutralization in the new era. In addition, the application can accurately measure and provide plant multi-angle observation hyperspectral reflectivity data, and this type of data is currently almost not available in the corresponding public data set type, and this type of multi-angle data set can solve many difficult problems that limit the development of vegetation remote sensing.

[0097] Each of the embodiments in the specification is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other. Each of the embodiments focuses on the difference from other embodiments. In the description of the specification, the description of the terms "one preferred embodiment", "further", "specifically", "in this embodiment", and the like means that the specific features, structures, materials or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the embodiments of the specification. In the specification, the illustrative description of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any appropriate manner in any one or more embodiments or examples. Furthermore, the person skilled in the art can combine and combine the different embodiments or examples described in the specification and the features of the different embodiments or examples without contradiction.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can still modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacement for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application.

Claims

1. A two-way synchronous detection platform for plant sensing mechanisms and proximity physics, characterized in that, The platform includes a growth chamber system, which is equipped with a lighting system, a radiation detection system, a point cloud detection system, an angle control system, and a support platform. The growth chamber system is used to provide plants with constant temperature and humidity and effectively avoid the impact of external radiation on plant growth; The lighting system is used to provide plants with an incident light source close to the solar spectrum and an isotropic parallel light source; The radiation detection system is used to acquire the photosynthetic radiation PAR received by the plant and to measure the radiation value reflected by the plant. The point cloud detection system is used to observe changes in the shape and growth of plants, and to study the structural and biochemical characteristics of plants by obtaining the reflectivity of plant point clouds based on the point cloud data. The angle control system is used to control the angles of the lighting system, radiation detection system and point cloud detection system respectively, to explore the growth of plants under different incident angles; The support platform is used to provide physical support for the lighting system, radiation detection system, and point cloud detection system; wherein: Under the photosynthetic radiation (PAR) received by the plant, the changes in plant growth caused by the interaction of phototropism and gravitational pull under the dual influence of gravity and light are observed through plant point cloud. The tilt angle of plant leaves relative to the lighting system is obtained. At the same time, multi-band reflectance data are obtained based on the scanned point cloud. The response of plant reflectance characteristics to different light source types is studied. The relationship between plant structural parameters and biochemical component content related to plant reflectance characteristics obtained based on point cloud reflectance data and plant tropism growth is determined. Based on the directional reflection characteristics of leaves measured at different azimuth angles under different lighting angles, the ecological attributes and biochemical content of the leaves are reflected, thereby reflecting the relationship between the biochemical state and growth status of the entire plant, and realizing a close-range physical quantitative study of the biochemical parameters of the whole plant.

2. The bidirectional synchronous detection platform for plant sensing mechanisms and proximity physics according to claim 1, characterized in that, The growth chamber system uses an opaque growth chamber with blackout curtains installed inside to provide a relatively enclosed space and reduce interference from natural light sources. The walls of the growth chamber are covered with black cloth to reduce the error caused by light reflection and multiple scattering on the walls, which would result in the non-phototropic surfaces of the plants also being exposed to light.

3. The bidirectional synchronous detection platform for plant sensing mechanisms and proximity physics according to claim 1, characterized in that, The support platform includes a support base plate, on which a base for placing plants is provided. The base plate can support the plants and can also rotate the plants at different angles, allowing the plants to rotate from a vertical state to an inclined state at different angles. A vertical support rod is provided on one side of the support base plate, and a horizontal support rod is provided on the upper part of the vertical support rod.

4. The bidirectional synchronous detection platform for plant sensing mechanisms and proximity physics according to claim 3, characterized in that, The lighting system includes a neon lamp, a searchlight, and a support plate; At least one neon lamp is installed on the vertical support rod via the support plate as a light source for plant growth. Each neon lamp is configured to be turned on independently to ensure that the light source only comes from the side and below the plant, making it easy to distinguish between the gravitational and phototropic properties of the tree. The support plate is made of dark-colored material. The searchlight is used to emit isotropic parallel light to illuminate the blades. The searchlight uses an isotropic light source, and the spectrum emitted by the isotropic light source is close to the solar spectrum.

5. The bidirectional synchronous detection platform for plant sensing mechanisms and proximity physics according to claim 4, characterized in that, The radiation detection system includes a photometer and a spectrometer; The photometer is used to measure the spectrum of the neon lamp tubes with different powers, and to measure the luminous flux reaching the stem of the seedling and the radiative flux of blue light, the main radiation for photosynthesis, at different tilt angles. The spectrometer is used to measure the reflected radiation of the blades observed from different angles, and to calculate the directional reflectance and BRDF of the blades.

6. The bidirectional synchronous detection platform for plant sensing mechanisms and proximity physics according to claim 5, characterized in that, The point cloud detection system uses lidar to scan plant morphology to obtain plant point clouds and acquire multi-band reflectance of the point clouds, which is used to gain a deeper understanding of the internal structural mechanisms and the influence of biochemical components on directional growth in plants.

7. The bidirectional synchronous detection platform for plant sensing mechanisms and proximity physics according to claim 6, characterized in that, The angle control system employs a ring-shaped device, which includes a rotatable and slidable first ring-shaped robotic arm, a second ring-shaped robotic arm, and a ring-shaped track. The ends of the first ring-shaped robotic arm, the second ring-shaped robotic arm, and the ring-shaped track are movably connected to the transverse support rod, wherein: The searchlight is mounted on the first annular robotic arm, which not only ensures that the searchlight appears at different azimuth angles of the plant, but also presents different zenith angles at different azimuth angles, which is more conducive to determining the directional reflection characteristics of the plant. The radiation receiving probe of the spectrometer is mounted on the second annular robotic arm to ensure that it receives the reflected radiation from plant leaves at different azimuth angles and different zenith angles, thereby obtaining the BRDF characteristics of the plant. The photometer, mounted on the second circular robotic arm, is capable of measuring the light flux reaching the trunk of the seedling at different tilt angles. The lidar, placed on the circular track, is capable of completely scanning the morphological features of the entire plant.

8. The two-way synchronous detection platform for plant sensing mechanism and proximity physics according to claim 7 further includes a reference plate, which is disposed on the support platform. The angle of the reference plate is adjustable and is used to perform distance correction and radiation intensity correction on the photometer and lidar, correcting errors that exist during use.

9. The bidirectional synchronous detection platform for plant sensing mechanisms and proximity physics according to claim 8, characterized in that, Based on the BRDF characteristics of the leaves calculated using the PROSPECULAR model, the biochemical content and surface roughness of the leaves are estimated non-contactly. Since BRDF is the ratio of two minimum values, it cannot be obtained directly; therefore, the BRF of the leaves is calculated first. The relationship between BRDF and BRF is as follows: in, It is a BRDF on the surface of a Lambertian matrix; Among them, dL leaf and dL reference These are the blade radiance and reference plate radiance measured at the same azimuth angle, respectively, ρ λ It is the reflectivity of the reference plate in this band.

10. A method of using a two-way synchronous detection platform based on the plant sensing mechanism and proximity physics as described in any one of claims 7-9, characterized in that, include: The effective photosynthetic radiation received by the plant under different power and incident angles of the neon lamp is directly measured by the photometer. The PAR and the radiant flux of blue light as photosynthesis are obtained based on the tilt angle and the lamp power integration. By using the plant point cloud acquired by the lidar, the changes in plant growth caused by the interaction of phototropism and gravitropism under the dual influence of gravity and light are observed. The tilt angle of plant leaves relative to the incident light source is obtained. At the same time, multi-band reflectance data are obtained based on the scanned point cloud to study the response of plant reflectance characteristics to different light source types. The relationship between plant structural parameters and biochemical component content related to plant reflectance characteristics and plant tropism growth is determined based on the point cloud reflectance data. Based on the directional reflectance characteristics of leaves measured at different azimuth angles using searchlights and spectrometers at different angles, the ecological attributes and biochemical content of the leaves are reflected, thereby reflecting the relationship between the biochemical state and growth status of the entire plant, and realizing close-sensory physical quantitative research on the biochemical parameters of the whole plant.

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