A method for detecting photosynthetic parameters of different layers of kelp

Abstract

The present invention discloses a method for detecting the photosynthetic parameters of different layers of kelp, belonging to the field of algae ecology. The method uses a specific device to slice and layer the kelp, and cross-sections the kelp leaf surface into the upper surface layer, the middle medullary layer, and the lower surface layer. The photosynthetic parameters of each layer are detected respectively to obtain the contribution of each layer to the photosynthesis of the kelp. The measurement results show that the parameters of the upper and lower cortical layers are significantly higher than those of the middle medullary layer, and the parameters of the lower layer are slightly higher; the measurement results of the content of each photosynthetic pigment show that the pigment content of the upper and lower cortical layers is significantly higher than that of the middle medullary layer, and the content of each pigment in the lower layer is slightly higher. The two measurement results are highly consistent, indicating that the present invention has carried out a relatively uniform stratification treatment on the kelp tissue. The present invention is simple to operate, easy to implement, has a small workload, and is highly efficient. It fundamentally solves the problem of measuring the photosynthetic parameters of each layer of kelp tissue.

Description

Technical Field

[0001] The present invention belongs to the field of algae ecology and specifically relates to a method for detecting photosynthetic parameters of different layers of kelp. Background Art

[0002] Kelp, an important economic large-scale brown algae, is the world's most productive cultivated large seaweed species. my country is the world's largest kelp farmer, producing nearly 90% of the world's total. Large-scale offshore kelp cultivation not only provides a rich source of raw materials for the food, chemical, and pharmaceutical industries, but also plays a crucial role in mitigating and remediating coastal eutrophication.

[0003] Research indicates that kelp exhibits a structural organization similar to that of terrestrial tree canopies, and that the canopy effect of its thallus optimizes the community's total photosynthesis. However, the optical properties and chemical microenvironment of kelp tissue, and their role in light harvesting and photosynthesis, remain understudied. Kelp is morphologically divided into upper and lower cortical layers and a central medullary layer, but lacks specialized cell types known from terrestrial systems, such as epidermal cells that focus light or palisade cells that facilitate carbon dioxide exchange and light funneling. In many macroalgae, a densely pigmented cortical lipid surrounds a more transparent medulla, which is hypothesized to have light-guiding properties in addition to its involvement in the translocation of photosensitized substances. Kelp's thallus exhibits differentiated plastids, with well-developed chloroplasts in the outer cortex and reduced thylakoid content in the medullary layer. It is currently unclear whether kelp's photosynthetic tissue exhibits an interplay between physical structure, light climate, and photosynthetic performance similar to the canopy interactions seen in terrestrial leaves.

[0004] Ecophysiological studies of macroalgal photosynthesis as a function of light are typically conducted by measuring variable chlorophyll fluorescence on the surface or by determining the photosynthetic pigment content of the entire tissue using gas chromatography. However, these methods share a common characteristic: the information retrieved is limited to the surface of the measured photosynthetic system; the photosynthetic efficiency of different layers of kelp has not been investigated in the prior art. Summary of the Invention

[0005] The purpose of the present invention is to provide a method for detecting the photosynthetic parameters of different layers of kelp. The method of the present invention slices and layers the kelp, and respectively detects the size of the photosynthetic parameters of each layer to obtain the contribution of each layer to the photosynthesis of the kelp.

[0006] The present invention is achieved through the following technical solutions:

[0007] A method for detecting photosynthetic parameters of different layers of kelp comprises slicing and stratifying the kelp, cross-cutting the kelp leaf surface into an upper surface layer, a middle pith layer and a lower surface layer, and detecting the size of the photosynthetic parameters of each layer respectively to obtain the contribution of each layer to the photosynthesis of the kelp.

[0008] Furthermore, the base of the kelp was selected for detection.

[0009] Furthermore, when kelp is horizontally layered, fresh kelp leaves must be used and cannot be frozen or embedded.

[0010] Furthermore, a device for stratifying fresh kelp leaves is provided, which includes a workbench, a slicer and a pressing piece; the workbench includes a machine tool that allows manual adjustment and a metal gasket. During operation, the metal gasket is fixed with the machine tool, and the sample is placed on the metal gasket. The sample is then pressed with the pressing piece, and the slicing operation is performed with a knife holder equipped with a blade.

[0011] As a preferred embodiment, the workbench consists of a machine tool and a metal gasket. The machine tool includes three fixed blocks of the same size, namely the first fixed block, the second fixed block and the third fixed block. Two metal rods connect the first fixed block, the second fixed block and the third fixed block in series, and the upper ends of the three fixed blocks remain horizontal. The first fixed block and the third fixed block are fixed on the connecting rod. The second fixed block located in the middle can move along the connecting rod. The second fixed block and the third fixed block are passed through a manually rotated threaded rod. The threaded rod is horizontal with the metal rod. The threaded rod can make the second fixed block move along the metal rod, thereby fixing the metal gasket together with the outermost first fixed block.

[0012] As a preferred embodiment, the workbench consists of a machine tool and a metal gasket; the metal gasket is made of two metal sheets, one long and one short, stacked and bonded together, and the groove formed by the two sheets of different lengths is the sample fixing groove.

[0013] As a preferred embodiment, the slicer consists of a knife holder and a blade; the knife holder is an inverted "U"-shaped metal block, and a slit is provided at the top of each arm of the "U"-shaped metal block for fixing the blade, and the edge of the blade is perpendicular to the two arms of the "U"-shaped metal block.

[0014] As a preferred embodiment, this device uses a frosted acrylic sheet as a pressing plate. Since kelp tissue has a high amount of gelatin on its surface, the frosted surface provides a good fixation for the pressing plate when slicing. Furthermore, the acrylic's translucency allows for a clear view of the sample's position during slicing.

[0015] The beneficial effects of the present invention compared with the prior art are as follows:

[0016] When measuring the chlorophyll fluorescence parameters and photosynthetic pigment content of tissues in different layers of kelp, the present invention selected the thicker basal tissue of the kelp for slicing and evenly divided the tissue into three layers. The measurement results of the chlorophyll fluorescence parameter Fv / Fm and the light response curve showed that the parameters of the upper and lower cortical layers were significantly higher than those of the middle medulla layer, and the parameters of the lower layer were slightly higher; the measurement results of the content of each photosynthetic pigment showed that the pigment content of the upper and lower cortical layers was significantly higher than that of the middle medulla layer, and the content of each pigment in the lower layer was slightly higher. The two measurement results were highly consistent, indicating that the present invention has carried out a relatively uniform stratification treatment on the kelp tissue. The present invention is simple to operate, easy to implement, has a small workload, and is highly efficient, and fundamentally solves the problem of measuring the photosynthetic parameters of each layer of kelp tissue.

[0017] The present invention solves the difficulties and safety hazards of current manual slicing of kelp tissue through a self-made slicing device. The working table of the slicing device can adjust the thickness of the slices, the pressing plate effectively fixes the kelp tissue, and the slicer improves the stability and safety of the slicing process. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the three-dimensional structure of the slicing device according to embodiment 1 of the present invention;

[0019] Figure 2 Schematic diagram of the three-dimensional structure of the slicing device machine tool in Example 1 of the present invention;

[0020] Figure 3 This is a schematic diagram of the three-dimensional structure of the metal gasket of the slicing device in Example 1 of the present invention;

[0021] Figure 4 Schematic diagram of the three-dimensional structure of the slicer of Example 1 of the present invention; a, front view, b, bottom view;

[0022] Figure 5 This is a histogram of the photosynthetic pigment content of different layers of the kelp base in Example 2 of the present invention;

[0023] Figure 6 This is a histogram of chlorophyll fluorescence parameters Fv / Fm of different layers at the base of kelp in Example 2 of the present invention;

[0024] Figure 7 This is a trend diagram of the light response curves of different layers at the base of kelp in Example 2 of the present invention.

[0025] In the figure: 1. slicer, 2. metal gasket, 3. first fixed block, 4. second fixed block, 5. third fixed block, 6. metal rod, 7. threaded rod, 8. groove, 9. knife holder, 10. blade. DETAILED DESCRIPTION

[0026] The technical solutions of the present invention will be clearly and completely described below in conjunction with specific embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

[0027] Example 1

[0028] A method for detecting photosynthetic parameters of different layers of kelp, comprising slicing and stratifying the kelp, cross-cutting the kelp leaf surface into an upper surface layer, a middle pith layer, and a lower surface layer, detecting the size of the photosynthetic parameters of each layer respectively to obtain the contribution of each layer to the photosynthesis of the kelp; and selecting the base of the kelp for detection.

[0029] The kelp is cut into three layers transversely using a slicing device such as Figure 1 As shown, it includes a workbench, a slicer 1 and a pressing piece made of acrylic material.

[0030] like Figure 2-3 As shown,

[0031] The workbench consists of a machine tool and a metal gasket 2. The machine tool includes three fixed blocks of the same size, namely the first fixed block 3, the second fixed block 4 and the third fixed block 5. Two metal rods 6 connect the three fixed blocks in series, and the upper ends of the three fixed blocks remain horizontal. The first fixed block 3 and the third fixed block 5 are fixed on the connecting rod. The second fixed block 4 in the middle can move along the connecting rod. The second fixed block 4 and the third fixed block 5 are passed through a manually rotated threaded rod 7. Rotating the threaded rod 7 can make the second fixed block 4 move along the connecting rod, thereby fixing the metal gasket 2 together with the outermost first fixed block 3, and the horizontal position of the gasket can be finely adjusted by manually rotating the threaded rod 7 of the machine tool.

[0032] As a preferred embodiment, the workbench consists of a machine tool and a metal gasket 2; the metal gasket 2 is made of two metal sheets, one long and one short, glued together, and the groove 8 formed by the two sheets of different lengths is the sample fixing groove.

[0033] As a preferred embodiment, Figure 4 As shown, the slicer 11 consists of a knife holder 9 and a blade 10; the blade 10 is a blade specially used for cryo-microtome. The knife holder 9 is an inverted "U"-shaped metal block. The top of each arm of the "U"-shaped metal block is provided with a slit for fixing the blade 10. The edge of the blade 10 is perpendicular to the two arms of the "U"-shaped metal block. As a preferred embodiment, the distance between the two arms of the "U"-shaped metal block is greater than the width of the first fixing block 3 and the second fixing block 2 after fixing the metal gasket 2.

[0034] As a preferred embodiment, this device uses a frosted acrylic plate as a pressing plate to press against the sample during slicing. Since kelp tissue has a high amount of colloid on its surface, the frosted surface provides a good fixation, and the acrylic's translucency allows for a clear view of the sample's position during slicing.

[0035] A thicker kelp base tissue sample was selected and trimmed into a rectangular shape for pre-slicing. During slicing, the relatively flat cross-section of the sample was pressed against the groove 8 formed by the two metal plates that make up the metal gasket 2. The slicer 1 was placed on the two fixed blocks that fixed the metal gasket 2. One hand pressed the kelp tissue sample with an acrylic pressing piece, and the other hand slowly pushed the slicer 1. When the blade 10 pressed against the groove 8, the sliding slicer 1 stopped, and the slicing operation was completed. The thickness of the cut tissue slice was measured using a macrometer, and the measurement result was the initial slice thickness. After that, the sample was selected for the formal experiment and its overall thickness was measured using a macrometer. One-third of the measurement result was the slice thickness required for the experiment. The result was compared with the initial slice thickness to adjust the height of the metal gasket 2 stuck between the first fixed block 3 and the second fixed block 4 so that the sample to be cut was higher than the upper surface of the first fixed block 3 and the second fixed block 4. After adjusting the height, two formal slicing processes were performed to obtain a three-layer kelp base tissue sample with uniform thickness. The samples were placed in a culture dish filled with seawater and stored at 10°C until use.

[0036] Example 2 Determination of photosynthetic parameters of different layers at the base of kelp

[0037] The slicing-processed kelp base tissue sample obtained in Example 1 was subjected to gas chromatography to determine the content of photosynthetic pigments such as chlorophyll a, chlorophyll c, and violaxanthin. Figure 5 It can be clearly seen that photosynthetic pigments are mainly concentrated in the upper and lower cortical layers of kelp tissue, the middle medulla layer has less pigment content, and the pigment content of the lower cortical layer is slightly higher than that of the upper cortical layer.

[0038] The sliced kelp base tissue sample obtained in Example 1 was subjected to the determination of chlorophyll fluorescence parameters Fv / Fm and light response curve by a PAM instrument. Figure 6 It can be seen that the Fv / Fm values of the upper and lower cortical layers are significantly higher than those of the middle medulla layer, and the value of the lower cortical layer is slightly higher than that of the upper layer. The measurement results are basically consistent with the content of photosynthetic pigments. Figure 7 As can be seen, the peak values of the light response curves for the upper and lower cortical layers are significantly higher than those for the middle medulla layer, and the peak value for the lower cortical layer is slightly higher than that for the upper layer. These results are consistent with the photosynthetic pigment content and the chlorophyll fluorescence parameter Fv / Fm. The high consistency of the test results for these three photosynthetic parameters indicates that the slicing device provided by the present invention achieves relatively uniform stratification of kelp tissue.

[0039] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for detecting photosynthetic parameters of different layers of kelp, characterized in that: The kelp was sliced and layered, and the leaf surface of the kelp was cut into the upper surface layer, the middle pith layer and the lower surface layer. The photosynthetic parameters of each layer were tested to obtain the contribution of each layer to the photosynthesis of the kelp. The method uses a device for slicing fresh kelp leaves, the device comprising a workbench, a slicer, and a pressing sheet; the workbench comprises a machine tool that allows manual adjustment and a metal gasket; during operation, the metal gasket is fixed by the machine tool, a sample is placed on the gasket, the sample is then pressed with the pressing sheet, and a knife holder equipped with a blade is used for slicing; the metal gasket is formed by laminating and gluing two metal sheets, one long and one short, together; the groove formed by the two sheets of different lengths serves as a sample fixing groove; The machine tool includes three fixed blocks of the same size: a first fixed block, a second fixed block, and a third fixed block. Two metal rods connect the three fixed blocks in series, and the upper ends of the three fixed blocks are kept horizontal. The first and third fixed blocks are fixed to the connecting rod. The second fixed block in the middle can move along the connecting rod. The second and third fixed blocks are penetrated by manually rotating threaded rods. Rotating the threaded rods can move the second fixed block along the connecting rod, thereby clamping and fixing the metal gasket together with the outermost first fixed block. The slicer consists of a knife holder and a blade; the knife holder is an inverted "U"-shaped metal block, and a slit is provided at the top of each arm of the "U"-shaped metal block for fixing the blade, and the edge of the blade is perpendicular to the two arms of the "U"-shaped metal block.

2. A method for detecting photosynthetic parameters of different layers of kelp according to claim 1, characterized in that, The base of the kelp was selected for testing.

3. A method for detecting photosynthetic parameters of different layers of kelp according to claim 1, characterized in that: The surface of the pressing sheet is a frosted surface.

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