Method for detecting light ecological adaptation type of phytoplankton

Abstract

The invention discloses a phytoplankton light ecological adaptation type detection method, which comprises the following steps: (1) determining a first decline light curve with a step length of 10 s, (2) determining a second decline light curve with a step length of 120 s, (3) fitting to obtain a decline light curve equation: y = y0 + a * exp (-b * x), and (4) comparing the y0 and the b of the phytoplankton under the first descending light curve with the y0 and the b of the phytoplankton under the second descending light curve to determine the photosynthetic ecological adaptation type of the phytoplankton. According to the method, the light ecological adaptation type of the phytoplankton can be rapidly determined by comparing the fitting parameters of the descending light curves with different step lengths, and the method is convenient and rapid. According to the method, the response of the phytoplankton to the light intensity fluctuation is represented by the relationship between the photosynthesis efficiency and the light intensity, the calculation of the electron transfer rate in the conventional light curve determination is avoided, and the fitting equation is simplified.

Description

Technical Field

[0001] The invention relates to the technical field of phytoplankton ecological environment detection, and in particular to a method for detecting phytoplankton light ecological adaptability. Background Art

[0002] There are differences in light conditions in different aquatic ecosystems. As the main primary producers, changes in the community structure of phytoplankton are significantly affected by the light conditions of the water body. Changes in the phytoplankton community structure are mediated by the food chain (web), affecting the productivity and stability of the entire aquatic ecosystem. By identifying the ecological adaptation of phytoplankton to light, changes in the phytoplankton community structure under different light conditions can be predicted, providing basic parameters for ecosystem health assessment.

[0003] Previous studies usually used growth experiments to determine the optimal light intensity for phytoplankton, or determined the adaptability of phytoplankton to strong light by comparing the activity of the xanthophyll cycle. However, the growth-based judgment method is time-consuming and not conducive to rapid judgment; the determination of the xanthophyll cycle requires a large amount of organic extraction reagents and high-performance liquid chromatography, which is prone to secondary pollution and has certain technical requirements for operators.

[0004] Based on the above problems, the present invention discloses a rapid detection method applicable to the photoecological adaptation type of phytoplankton. By comparing the fitting parameters of the descending light curves with different step lengths, the photoecological adaptation type of phytoplankton can be identified within 30 minutes. Summary of the invention

[0005] The purpose of the present invention is to provide a method for detecting the light ecological adaptation type of phytoplankton, which can quickly detect and confirm the light ecological adaptation type of phytoplankton by comparing the fitting parameters of the falling light curves of different step lengths.

[0006] To this end, the present invention provides a method for detecting the light ecological adaptability of phytoplankton, comprising the following steps: (1) Determine the falling light curve with a step length of 10 s The phytoplankton was illuminated for 10 seconds, and the maximum fluorescence F under n light intensities was measured. m and minimum fluorescence F o , and calculate the photosynthesis efficiency under the corresponding light intensity; Draw a first declining light curve according to the n light intensities and corresponding photosynthesis efficiencies; (2) Determine the falling light curve with a step length of 120 s The phytoplankton was illuminated for 120 s, and the maximum fluorescence F at n light intensities was measured. m and minimum fluorescence F o , and calculate the photosynthesis efficiency under the corresponding light intensity; Draw a second declining light curve according to the n light intensities and corresponding photosynthesis efficiencies; (3) Fitting the falling light curve equation According to the first descending light curve and the second descending light curve, the descending light curve equation is fitted as follows: y= y0+ a·exp (-b·x); wherein x is the light intensity, y is the photosynthesis efficiency of phytoplankton when the light intensity is x, y0 is the limit photosynthesis efficiency of phytoplankton calculated by the equation, and b is the rate of change of photosynthesis efficiency with light intensity calculated by the equation; (4) Determining the photosynthetic ecological adaptability of the phytoplankton by comparing the values ​​of y0 and b of the phytoplankton under the first descending light curve and the values ​​of y0 and b under the second descending light curve.

[0007] Preferably, when the frequency of light intensity change in the water body is 0.1-10 Hz, if y0 and b under the first descending light curve corresponding to the phytoplankton are greater than y0 and b under the second descending light curve, it means that the phytoplankton has strong adaptability to the water body; and the greater the difference between y0 and b under the first descending light curve and y0 and b under the second descending light curve, the stronger the adaptability of the phytoplankton to the water body.

[0008] Preferably, when the frequency of light intensity change in the water body is 0-0.1 Hz, if y0 and b under the second descending light curve corresponding to the phytoplankton are greater than y0 and b under the first descending light curve, it means that the phytoplankton has strong adaptability to the water body; and the greater the difference between y0 and b under the second descending light curve and y0 and b under the first descending light curve, the stronger the adaptability of the phytoplankton to the water body.

[0009] Preferably, in the step (1) and the step (2), photosynthesis efficiency = (F m -F o ) / F m .

[0010] Preferably, in step (1) and step (2), n is greater than or equal to 10, and the n light intensities decrease in sequence, with the minimum light intensity being 1 μmolphotons m -2 s -1 .

[0011] Preferably, in step (1) and step (2), the n light intensities include at least 5 first light intensities and at least 5 second light intensities, and the first light intensities are greater than or equal to 200 μmolphotons m -2 s -1 , the second light intensity is less than 200 μmolphotons m -2 s-1 .

[0012] Preferably, the difference between two adjacent first light intensities is greater than or equal to 50 μmolphotons m -2 s -1 , and less than or equal to 200 μmolphotons m -2 s -1 .

[0013] Preferably, the difference between two adjacent second light intensities is less than or equal to 50 μmolphotons m -2 s -1 .

[0014] Preferably, in step (1) and step (2), n=12, and the 12 light intensities are: 969 μmolphotonsm -2 s -1 、795μmolphotons m -2 s -1 、705μmolphotons m -2 s -1 、521μmolphotons m -2 s -1 、428μmolphotons m -2 s -1 、336μmolphotons m -2 s -1 、241μmolphotons m -2 s -1 、148μmolphotons m -2 s -1 、104μmolphotons m -2 s -1 、63μmolphotons m -2 s -1 、32μmolphotons m -2 s -1 , 1 μmolphotons m -2 s -1 .

[0015] Compared with the prior art, the advantages and positive effects of the present invention include: The invention can quickly determine the light ecological adaptability of phytoplankton by comparing the fitting parameters of the falling light curves with different step lengths, which is convenient and quick.

[0016] The descending light curve can more truly reflect the adaptability of phytoplankton to light and can avoid the instantaneous light adaptation caused by the sequential increase of light intensity during conventional light curve measurement.

[0017] The present invention characterizes the influence of phytoplankton on light intensity fluctuation by the relationship between photosynthesis efficiency and light intensity, avoids the calculation of electron transfer rate in conventional light curve measurement, and simplifies the fitting equation.

[0018] After reading the specific embodiments of the present invention in conjunction with the accompanying drawings, other features and advantages of the present invention will become more clear. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 are the first descending light curve and the second descending light curve corresponding to the detection of phytoplankton in Example 1 of the present invention; Figure 2 These are the first descending light curve and the second descending light curve corresponding to the detection of phytoplankton in Example 2 of the present invention. DETAILED DESCRIPTION

[0020] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0021] The present invention provides a method for detecting the light ecological adaptability of phytoplankton, comprising the following steps: (1) Determine the falling light curve with a step length of 10 s The phytoplankton was illuminated for 10 s and the maximum fluorescence F at n light intensities was measured. m and minimum fluorescence F o , and calculate the photosynthesis efficiency under the corresponding light intensity; Draw a first declining light curve according to the n light intensities and corresponding photosynthesis efficiencies; (2) Determine the falling light curve with a step length of 120 s The phytoplankton was illuminated for 120 seconds, and the maximum fluorescence F was measured at n light intensities. m and minimum fluorescence F o , and calculate the photosynthesis efficiency under the corresponding light intensity; Draw a second declining light curve according to the n light intensities and corresponding photosynthesis efficiencies; (3) Fitting the falling light curve equation According to the first descending light curve and the second descending light curve, the descending light curve equation is fitted as follows: y= y0+ a·exp (-b·x); wherein x is the light intensity, y is the photosynthesis efficiency of phytoplankton when the light intensity is x, y0 is the limit photosynthesis efficiency of phytoplankton calculated by the equation, and b is the rate of change of photosynthesis efficiency with light intensity calculated by the equation; (4) Determining the photosynthetic ecological adaptability of the phytoplankton by comparing the values ​​of y0 and b of the phytoplankton under the first descending light curve and the values ​​of y0 and b under the second descending light curve.

[0022] Preferably, when the frequency of light intensity change in the water body is 0.1-10 Hz (dramatic light intensity change), if y0 and b under the first descending light curve corresponding to the phytoplankton are greater than y0 and b under the second descending light curve, it means that the phytoplankton has strong adaptability to the water body; and the greater the difference between y0 and b under the first descending light curve and y0 and b under the second descending light curve, the stronger the adaptability of the phytoplankton to the water body.

[0023] Preferably, when the frequency of light intensity change in the water body is 0-0.1 Hz (light intensity changes slowly), if y0 and b under the second descending light curve corresponding to the phytoplankton are greater than y0 and b under the first descending light curve, it means that the phytoplankton has strong adaptability to the water body; and the greater the difference between y0 and b under the second descending light curve and y0 and b under the first descending light curve, the stronger the adaptability of the phytoplankton to the water body.

[0024] The present invention uses a first descending light curve to simulate a water body with drastic changes in light intensity, and uses a second descending light curve to simulate a water body with slow changes in light intensity. If y0 and b of the first descending light curve of phytoplankton are both greater than y0 and b under the second descending light curve, it means that the phytoplankton has a strong adaptability to water bodies with drastic changes in light intensity. If y0 and b of the second descending light curve of phytoplankton are both greater than y0 and b under the first descending light curve, it means that the phytoplankton has a strong adaptability to water bodies with slow changes in light intensity. Through the above method, the present invention can conveniently and quickly detect and determine the light ecological adaptability type of phytoplankton.

[0025] Preferably, in the step (1) and the step (2), photosynthesis efficiency = (F m -F o ) / F m .

[0026] Preferably, in step (1) and step (2), n is greater than or equal to 10, and the n light intensities decrease in sequence, with the minimum light intensity being 1 μmolphotons m -2 s -1 .

[0027] Preferably, in step (1) and step (2), the n light intensities include at least 5 first light intensities and at least 5 second light intensities, and the first light intensities are greater than or equal to 200 μmolphotons m -2 s -1 , the second light intensity is less than 200 μmolphotons m -2 s -1 .

[0028] Preferably, the difference between two adjacent first light intensities is greater than or equal to 50 μmolphotons m -2 s -1 , and less than or equal to 200 μmolphotons m -2 s -1 .

[0029] Preferably, the difference between two adjacent second light intensities is less than or equal to 50 μmolphotons m -2 s -1 .

[0030] Preferably, in step (1) and step (2), n=12, and the 12 light intensities are: 969 μmolphotonsm -2 s -1 、795μmolphotons m -2 s -1 、705μmolphotons m -2 s -1 、521μmolphotons m -2 s -1 、428μmolphotons m -2 s -1 、336μmolphotons m -2 s -1 、241μmolphotons m -2 s -1 、148μmolphotons m -2 s -1 、104μmolphotons m -2 s -1 、63μmolphotons m -2 s -1 、32μmolphotons m -2 s -1 , 1 μmolphotons m -2 s -1 . Example

[0031] The phytoplankton in this embodiment is flat algae living in closed culture ponds.

[0032] The method for detecting the light ecological adaptation type of phytoplankton in this embodiment comprises the following steps: (1) Determine the falling light curve with a step length of 10 s The phytoplankton was illuminated and the light intensity was adjusted to 969 μmolphotons m 2 s -1 After 10 s of illumination, a saturation pulse was applied again and the maximum fluorescence F at this light intensity was measured. m and minimum fluorescence F o , and calculate the photosynthesis efficiency (F m -F o ) / F m ; The light intensity was then adjusted down to 795 μmolphotons m -2 s -1 、705μmolphotons m -2 s -1 、521μmolphotons m -2 s -1 、428μmolphotons m -2 s -1 、336μmolphotons m -2 s -1 、241μmolphotons m -2 s -1 、148μmolphotons m -2 s -1 、104μmolphotons m -2 s -1 、63μmolphotons m -2 s -1 、32μmolphotonsm -2 s -1 , 1 μmolphotons m -2 s -1 The step length of illumination corresponding to each light intensity is 10 s, and the photosynthesis efficiency corresponding to each light intensity is calculated.

[0033] The first declining light curve is drawn according to the above 12 light intensities and the corresponding photosynthesis efficiency, such as Figure 1 As shown, the curve corresponding to the solid circle is the first falling light curve.

[0034] (2) Determine the falling light curve with a step length of 120 s The phytoplankton was illuminated and the light intensity was adjusted to 969 μmolphotons m -2 s -1 After 120 s of illumination, a saturation pulse was applied again and the maximum fluorescence F at this light intensity was measured. m and minimum fluorescence F o , and calculate the photosynthesis efficiency (F m -F o ) / F m ; The light intensity was then adjusted down to 795 μmolphotons m -2 s -1 、705μmolphotons m -2 s -1 、521μmolphotons m -2 s -1 、428μmolphotons m -2 s -1 、336μmolphotons m -2 s -1 、241μmolphotons m -2 s -1 、148μmolphotons m -2 s -1 、104μmolphotons m -2 s -1 、63μmolphotons m -2 s -1 、32μmolphotonsm -2 s -1 , 1 μmolphotons m -2 s -1 The step length of illumination corresponding to each light intensity is 120 s, and the photosynthesis efficiency corresponding to each light intensity is calculated.

[0035] The second descending light curve is drawn according to the above 12 light intensities and the corresponding photosynthesis efficiency, such as Figure 1 As shown, the curve corresponding to the hollow circle is the second falling light curve.

[0036] (3) Fitting the falling light curve equation According to the first descending light curve and the second descending light curve, the descending light curve equation is fitted as follows: y= y0+ a·exp (-b·x); wherein x is the light intensity, y is the photosynthesis efficiency of phytoplankton when the light intensity is x, y0 is the limit photosynthesis efficiency of phytoplankton calculated by the equation, and b is the rate of change of photosynthesis efficiency with light intensity calculated by the equation; (4) The photosynthetic ecological adaptability of phytoplankton can be determined by comparing the values ​​of y0 and b under the first decreasing light curve and y0 and b under the second decreasing light curve.

[0037] The phytoplankton in this embodiment is flat algae living in a closed breeding pond. The light intensity of the water in the closed breeding pond changes slowly, and the frequency of the light intensity change of the water is usually 0-0.1 Hz.

[0038] Through detection, the y0 of the second descending light curve corresponding to the flat algae is -0.18, b is 0.011, and the y0 of the first descending light curve corresponding to the flat algae is -0.34, b is 0.010. The y0 and b of the second descending light curve corresponding to the flat algae are greater than the y0 and b of the first descending light curve corresponding to the flat algae, indicating that the flat algae have strong adaptability to water bodies with slow changes in light intensity; and the greater the difference between the y0 and b of the second descending light curve and the y0 and b of the first descending light curve, the stronger the adaptability of the flat algae to water bodies with slow changes in light intensity.

[0039] Through Example 1, it can also be verified that the detection method of the photosynthetic ecological adaptability type of phytoplankton of the present invention is correct. Example

[0040] The phytoplankton in this example is Prorocentrum donghaiense living in the red tide area of ​​the Yangtze River Estuary.

[0041] The method for detecting the light ecological adaptation type of phytoplankton in this embodiment comprises the following steps: (1) Determine the falling light curve with a step length of 10 s The phytoplankton was illuminated and the light intensity was adjusted to 969 μmolphotons m -2 s -1 After 10 s of illumination, a saturation pulse was applied again and the maximum fluorescence F at this light intensity was measured. m and minimum fluorescence F o , and calculate the photosynthesis efficiency (F m -F o ) / F m ; The light intensity was then adjusted down to 795 μmolphotons m -2 s -1 、705μmolphotons m-2 s -1 、521μmolphotons m -2 s -1 、428μmolphotons m -2 s -1 、336μmolphotons m -2 s -1 、241μmolphotons m -2 s -1 、148μmolphotons m -2 s -1 、104μmolphotons m -2 s -1 、63μmolphotons m -2 s -1 、32μmolphotonsm -2 s -1 , 1 μmolphotons m -2 s -1 The step length of illumination corresponding to each light intensity is 10 s, and the photosynthesis efficiency corresponding to each light intensity is calculated.

[0042] The first declining light curve is drawn according to the above 12 light intensities and the corresponding photosynthesis efficiency, such as Figure 2 As shown, the curve corresponding to the solid circle is the first falling light curve.

[0043] (2) Determine the falling light curve with a step length of 120 s The phytoplankton was illuminated and the light intensity was adjusted to 969 μmolphotons m -2 s -1 After 120 s of illumination, a saturation pulse was applied again and the maximum fluorescence F at this light intensity was measured. m and minimum fluorescence F o , and calculate the photosynthesis efficiency (F m -F o ) / F m ; The light intensity was then adjusted down to 795 μmolphotons m -2 s -1 、705μmolphotons m -2 s -1 、521μmolphotons m -2 s -1 、428μmolphotons m -2 s -1 、336μmolphotons m-2 s -1 、241μmolphotons m -2 s -1 、148μmolphotons m -2 s -1 、104μmolphotons m -2 s -1 、63μmolphotons m -2 s -1 、32μmolphotonsm -2 s -1 , 1 μmolphotons m -2 s -1 The step length of illumination corresponding to each light intensity is 120 s, and the photosynthesis efficiency corresponding to each light intensity is calculated.

[0044] The second descending light curve is drawn according to the above 12 light intensities and the corresponding photosynthesis efficiency, such as Figure 1 As shown, the curve corresponding to the hollow circle is the second falling light curve.

[0045] (3) Fitting the falling light curve equation According to the first descending light curve and the second descending light curve, the descending light curve equation is fitted as follows: y= y0+ a·exp (-b·x); wherein x is the light intensity, y is the photosynthesis efficiency of phytoplankton when the light intensity is x, y0 is the limit photosynthesis efficiency of phytoplankton calculated by the equation, and b is the rate of change of photosynthesis efficiency with light intensity calculated by the equation; (4) The photosynthetic ecological adaptability of phytoplankton can be determined by comparing the values ​​of y0 and b under the first decreasing light curve and y0 and b under the second decreasing light curve.

[0046] The phytoplankton in this embodiment is Prorocentrum donghaiense living in the red tide area of ​​the Yangtze River Estuary. The light intensity of the water body in the red tide area of ​​the Yangtze River Estuary changes dramatically, and the frequency of light intensity change of the water body is usually 0.1-10 Hz.

[0047] Through detection, the y0 of the first descending light curve corresponding to Prorocentrum donghaiense was 0.31 and b was 0.02, and the y0 of the second descending light curve corresponding to Prorocentrum donghaiense was -0.26 and b was 0.005. The y0 and b of the first descending light curve corresponding to Prorocentrum donghaiense were greater than the y0 and b of the second descending light curve corresponding to Prorocentrum donghaiense, indicating that Prorocentrum donghaiense has a strong adaptability to water bodies with drastic changes in light intensity; and the greater the difference between y0 and b under the first descending light curve and y0 and b under the second descending light curve, the stronger the adaptability of Prorocentrum donghaiense to water bodies with drastic changes in light intensity.

[0048] Through Example 2, it can also be verified that the detection method of the photosynthetic ecological adaptability type of phytoplankton of the present invention is correct.

[0049] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for a person skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to replace some of the technical features therein by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions claimed to be protected by the present invention.

Claims

1. A method for detecting the light ecological adaptability of phytoplankton, characterized in that: The steps include: (1) Determine the falling light curve with a step length of 10 s The phytoplankton was illuminated for 10 s and the maximum fluorescence F at n light intensities was measured. m and minimum fluorescence F o , and calculate the photosynthesis efficiency under the corresponding light intensity; Draw a first declining light curve according to the n light intensities and corresponding photosynthesis efficiencies; (2) Determine the falling light curve with a step length of 120 s The phytoplankton was illuminated for 120 seconds, and the maximum fluorescence F was measured at n light intensities. m and minimum fluorescence F o , and calculate the photosynthesis efficiency under the corresponding light intensity; Draw a second declining light curve according to the n light intensities and corresponding photosynthesis efficiencies; (3) Fitting the falling light curve equation According to the first descending light curve and the second descending light curve, the descending light curve equation is fitted as follows: y= y0+ a·exp (-b·x); wherein x is the light intensity, y is the photosynthesis efficiency of phytoplankton when the light intensity is x, y0 is the limit photosynthesis efficiency of phytoplankton calculated by the descending light curve equation, and b is the rate of change of photosynthesis efficiency with light intensity calculated by the descending light curve equation; (4) Determining the photosynthetic ecological adaptability of the phytoplankton by comparing the values ​​of y0 and b of the phytoplankton under the first descending light curve and the values ​​of y0 and b under the second descending light curve.

2. The method for detecting the light ecological adaptation type of phytoplankton according to claim 1, characterized in that: When the light intensity variation frequency of the water body is 0.1-10 Hz, if y0 and b under the first descending light curve corresponding to the phytoplankton are greater than y0 and b under the second descending light curve, it means that the phytoplankton has strong adaptability to the water body; The greater the difference between y0 and b under the first descending light curve and y0 and b under the second descending light curve, the stronger the adaptability of phytoplankton to the water body.

3. The method for detecting the light ecological adaptation type of phytoplankton according to claim 1, characterized in that: When the light intensity variation frequency of the water body is 0-0.1 Hz, if y0 and b under the second descending light curve corresponding to the phytoplankton are greater than y0 and b under the first descending light curve, it means that the phytoplankton has strong adaptability to the water body; The greater the difference between y0 and b under the second descending light curve and y0 and b under the first descending light curve, the stronger the adaptability of phytoplankton to the water body.

4. The method for detecting the light ecological adaptation type of phytoplankton according to claim 1, characterized in that: In the step (1) and the step (2), photosynthesis efficiency = (F m -F o ) / F m .

5. The method for detecting the light ecological adaptation type of phytoplankton according to claim 1, characterized in that: In the step (1) and the step (2), n is greater than or equal to 10, and the n light intensities decrease in sequence, with the minimum light intensity being 1 μmolphotons m -2 s -1 .

6. The method for detecting the light ecological adaptation type of phytoplankton according to claim 1, characterized in that: In step (1) and step (2), the n light intensities include at least 5 first light intensities and at least 5 second light intensities, and the first light intensities are greater than or equal to 200 μmolphotons m -2 s -1 , the second light intensity is less than 200 μmolphotons m -2 s -1 .

7. The method for detecting the light ecological adaptation type of phytoplankton according to claim 6, characterized in that: The difference between two adjacent first light intensities is greater than or equal to 50 μmolphotons m -2 s -1 , and less than or equal to 200 μmolphotons m -2 s -1 .

8. The method for detecting the light ecological adaptation type of phytoplankton according to claim 6, characterized in that: The difference between two adjacent second light intensities is less than or equal to 50 μmolphotons m -2 s -1 .

9. The method for detecting the light ecological adaptation type of phytoplankton according to claim 1, characterized in that: In the step (1) and the step (2), n=12, and the 12 light intensities are: 969 μmolphotons m -2 s -1 、795μmolphotons m -2 s -1 、705μmolphotons m -2 s -1 、521μmolphotons m -2 s -1 、428μmolphotonsm -2 s -1 、336μmolphotons m -2 s -1 、241μmolphotons m -2 s -1 、148μmolphotons m -2 s -1 、104μmolphotons m -2 s -1 、63μmolphotons m -2 s -1 、32μmolphotons m -2 s -1 , 1 μmolphotons m -2 s -1 .

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