JPH0815157A - Plankton sensor in water - Google Patents

Abstract

PURPOSE:To obtain a small-sized lightweight sensor for measuring the plankton while classifying into plant plankton having chlorophyll pigment and indigo alga having phycobilins pigment. CONSTITUTION:Underwater environment is irradiated sequentially with light having wavelength in the range of 420-520nm (first wavelength) and 540-580nm (second wavelength) emitted from a LED 12. A light receiving section 13 receives fluorescence in the wavelength range of 640-680nm radiated from a plant plankton and an indigo alga, respectively, upon irradiation with first and second wavelength.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sensor for measuring the amount of plankton in water, and more particularly to a method for measuring the amount of plankton in water by a submersion system without collecting a sample.

[0002]

2. Description of the Related Art The amount of plankton in water is measured by collecting water and analyzing it in a laboratory. With this method, it is difficult to measure the true amount of plankton for water in deep areas, where changes in water pressure when pulled up to the surface of the water and changes due to contact with air cannot be avoided. Further, it requires manpower for sampling, transporting, and measuring, and is not suitable for measuring many samples.

For this reason, various attempts have been made to develop a plankton sensor of the water submersion type, but at present, it is large and expensive, and is only used for research. As the underwater type plankton sensor for the research,
Alec Electronics Co., Ltd. chlorotech ACL-100
Although there is a (trade name), the weight in air is as large as 6 kg or more and the excitation wavelength is only 410 to 470 nm, so that there is a problem that only phytoplankton having a chlorophyll pigment can be measured.

[0004] In recent years, along with the development of aquaculture, it has been required to move the school of fish in accordance with the occurrence of plankton in the water. In this case, the plankton in the water can be quickly moved in many places over time. However, there is a problem that the large and expensive one cannot handle this.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a plankton sensor which is lightweight, easy to handle, inexpensive, and capable of measuring plankton other than phytoplankton having a chlorophyll pigment.

[0006]

According to the present invention, a light emitting diode has excitation wavelengths of 420 to 520 nm and 540 to 5 nm.
The amount of phytoplankton in water having a chlorophyll pigment is obtained by sequentially irradiating water with 80 nm and 640 to 740 nm in water to excite the dye contained in the underwater plankton by the former two and receiving the emitted fluorescence by the light receiving part of 640 to 680 nm. And the amount of cyanobacteria having a phycobilin pigment in water are separately quantified, and irradiation light of 640 to 740 nm is received by the light receiving unit as back light scattering to quantify the amount of suspended solids in water. Plankton sensor.

Further, the present invention is characterized in that a water temperature sensor, a conductivity measuring sensor and a water depth measuring sensor are added.

[0008]

According to the present invention, the light emitting diode allows
20 to 520 nm (first wavelength), 540 to 580 nm
Light of (second wavelength) and light of 640 to 740 nm (third wavelength) are sequentially irradiated into water. By the first wavelength,
Excite the chlorophyll pigment of phytoplankton in water,
The 640 to 680 nm emitted fluorescent light is received by the light receiving unit,
The amount of chlorophyll in phytoplankton is quantified from the amount of received light. Further, the phycobilin pigment of cyanobacteria in water is excited by the second wavelength, and the emitted fluorescence of 640 to 680 nm is received by the light receiving part, and the amount of phycobilin in cyanobacteria is quantified from the received light amount. Further, the light receiving section receives the scattered light due to the back light scattering by the suspension in water by the third wavelength, and the amount of the suspension in water is quantified from the received light amount.

Since the generation of plankton is closely related to the water temperature, the salt concentration in water and the water depth, it is preferable to additionally add a water temperature sensor, a water conductivity sensor and a water depth sensor. As these sensors, conventionally used sensors are incorporated and used.

[0010]

The present invention will be described in more detail with reference to the following examples.

FIG. 1 is an overall sectional view of an underwater plankton sensor (hereinafter referred to as "this device") 1 according to an embodiment of the present invention. The device 1 is divided into a lower sensor part 2 and an upper control part 3, both parts of which are screw-connected with each other, and the outside is made of a rigid and pressure-resistant plastic. The control unit 3 is connected by a cable 5 to a measurement base on the ground (not shown). The sensor unit 2 includes a water depth sensor 11, a light emitting diode 12, a light receiving unit 13, a conductivity measuring electrode 14, and a temperature sensor 15 from the tip. The control unit 3 is provided with a central processing unit (CPU) that receives and calculates data from each power source and each sensor for operating these, and stores or transfers the calculation result based on a command from the measurement base.

The light emitting diode 12 which is the center of the device 1.
Is composed of a full-color LED lamp, and the relationship between the wavelength of its continuous spectrum and the light intensity is shown in FIG. A voltage is applied to the light emitting diode 12 to cause it to emit light, and the light to be irradiated into the water is 420 to 520 nm (first wavelength) and 520 to 580 n by the optical glass filter provided on the front surface thereof.
m (second wavelength) and 640-740 nm (third wavelength) wavelength range. And the light emitting diode 12
The front surface of the light receiving portion 13 is made of pressure-resistant transparent plastic.

As shown in FIG. 3, when phytoplankton having chlorophyll excited by the light of the first wavelength is in the irradiation range, it emits fluorescence of 640 to 680 nm. This fluorescence is received by the light receiving unit 13. The amount of phytoplankton in the irradiation range is proportional to the amount of fluorescence emitted when the intensity of the excitation light is constant, so that the amount of phytoplankton can be measured from the amount of received light. The quantitative range of the device 1 is 0 to 100 μg / L, and the resolution is 0.01 μm.
g / L. The same applies to the quantification of cyanobacteria having a phycobilin pigment with light of the second wavelength. These are called fluorescence intensity methods, and the present invention does this using two wavelengths.

When the light of the third wavelength is applied to the suspension in water, the light of the same wavelength is reflected. Since this reflected light is also proportional to the amount of suspended matter in the light irradiation range, the amount of suspended matter in water can be measured from the amount of light received by the light receiving section. The quantitative range of the device 1 is 0 to 1000 FTU, and the resolution is 0.1 FTU.
Is.

The measuring range of the light emitting diode 12 and the light receiving portion 13 is about 5 cm in front of the device in the shaded portion in FIG.

FIG. 5 is a sectional view taken along the line VV of FIG. Here, a three-electrode type electrode 14 is provided so as to face the outer surface of the main body.
It is measured with 1 to 4%, 0.0005% resolution and 0.001% accuracy. A thermistor type thermometer 15 is provided on the outer surface of the main body, and the water temperature is in the range of -5 to 35 ° C.
It can be obtained with a resolution of 0.002 deg and an accuracy of 0.01 deg.

A strain gauge type water depth gauge is provided at the tip of the present apparatus 1, and the strain gauge type water gauge is 0 to 70 m, 0 to 350 m, 0.
The water depth is measured with 0.1% FS linearity with a resolution of 0.01% FS, switching to a water depth in the range of -700 m, 0-2100 m or 0-3500 m.

The measurement is carried out by the built-in clock at intervals designated by one second or more and transmitted to the measurement base. As a result, the plankton around the fish farm is divided into phytoplankton and cyanobacteria, and the amount of suspended solids, water temperature, conductivity, and water depth are simultaneously transmitted to the measurement base over time, allowing quick movement of the school of fish. it can. In addition, data at a location far away from the measurement base is stored in the device 1 without being transmitted.

Further, the first wavelength and the second wavelength selected here are within a range where there is no interference due to Raman scattering of water as shown in Table 1.

[0020]

[Table 1]

Further, since the light emitting diode is used as the light source, the present apparatus 1 can be lightened to about 1 kg and downsized, and water temperature, conductivity, water depth and suspended matter can be measured simultaneously.

[0022]

As described above, according to the present invention, a light emitting diode can be used in the range of 420 to 520 nm and 540 to 58 nm.
By irradiating water with a wavelength of 0 nm, the plankton in the water can be separately quantified by dividing it into phytoplankton having a chlorophyll pigment and cyanobacteria having a phycobilin pigment, and the weight and size can be reduced. In addition, water temperature, conductivity, water depth, and the amount of suspended matter, which are closely related to the plankton measurement, can be measured at the same time.

[Brief description of drawings]

FIG. 1 is a sectional view of an embodiment of the present invention.

FIG. 2 is a graph showing a relationship between wavelength and light intensity of a light emitting diode used in the present invention.

[Fig. 3] When the plankton 21 of a plant is irradiated with light,
It is explanatory drawing explaining the state which emits fluorescence.

FIG. 4 is an explanatory diagram showing a range measured by the device.

5 is a cross-sectional view taken along the section line VV in FIG.

[Explanation of symbols]

 1 Plankton sensor (this device) 2 Sensor section 3 Control section 5 Cable 11 Water depth sensor 12 Light emitting diode 13 Light receiving section 14 Electrode 15 Temperature sensor

Claims (2)

[Claims] 1. A light emitting diode having an excitation wavelength of 42
0-520 nm, 540-580 nm and 640-7
Light of 40 nm is sequentially irradiated into water, and the former two excite the dye contained in the plankton in water to emit fluorescence of 64 nm.
The amount of phytoplankton in water having a chlorophyll pigment and the amount of cyanobacteria having a phycobilin pigment in water were separately quantified by receiving light with a light receiving unit of 0 to 680 nm, 640
An underwater plankton sensor, characterized in that irradiation light of ˜740 nm is received by the light receiving unit as backscattering light and the amount of suspended matter in water is quantified. 2. The underwater plankton sensor according to claim 1, further comprising a water temperature sensor, a conductivity measuring sensor and a water depth measuring sensor.