US 11,913,885 B2
Method and apparatus for calculating abundance of specific species of phytoplankton, and method and apparatus for detecting sign of red tide occurrence caused by specific species of phytoplankton
Mitsuo Yoshida, Nishinomiya (JP); and Hiroharu Kato, Nishinomiya (JP)
Assigned to JFE ADVANTECH CO., LTD., Hyogo (JP)
Appl. No. 17/598,420
Filed by JFE Advantech Co., Ltd., Hyogo (JP)
PCT Filed Feb. 20, 2020, PCT No. PCT/JP2020/006889
§ 371(c)(1), (2) Date Sep. 27, 2021,
PCT Pub. No. WO2020/195412, PCT Pub. Date Oct. 1, 2020.
Claims priority of application No. 2019-061670 (JP), filed on Mar. 27, 2019.
Prior Publication US 2022/0163451 A1, May 26, 2022
Int. Cl. G01N 21/64 (2006.01); A01K 61/13 (2017.01)
CPC G01N 21/6486 (2013.01) [A01K 61/13 (2017.01); G01N 2201/062 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A method for calculating an abundance of specific species of phytoplankton, the method comprising:
irradiating a reference sample containing a phytoplankton group with excitation light, the phytoplankton group containing a plurality of kinds of phytoplankton, the plurality of kinds of phytoplankton possibly including specific species of phytoplankton, and the specific species of the phytoplankton emitting fluorescence by absorbing the excitation light;
measuring an intensity of the fluorescence emitted from the reference sample in each of two wavelength bands and calculating a reference sample intensity ratio that is a ratio of intensities of these two;
measuring a reference sample total fluorescence intensity that is an intensity in a substantially entire wavelength band of the fluorescence emitted from the reference sample;
counting a reference abundance of the specific species of the phytoplankton contained in the reference sample;
calculating an other species plankton intensity ratio, that is a ratio of intensities in the two wavelength bands of the fluorescence emitted from other species of a phytoplankton other than the specific species of the phytoplankton in the phytoplankton group, based on the reference sample intensity ratio, the reference sample total fluorescence intensity, and the reference abundance;
irradiating an analysis sample, which is expected to have similarity with the reference sample with respect to composition of the phytoplankton group, with excitation light;
measuring an intensity of the fluorescence emitted from the analysis sample in each of the two wavelength bands and calculating an intensity ratio that is a ratio of intensities of these two;
measuring a total fluorescence intensity that is an intensity in a substantially entire wavelength band of the fluorescence emitted from the analysis sample; and
calculating an abundance of the specific species of the phytoplankton that may be contained in the analysis sample based on the other species plankton intensity ratio, the intensity ratio, and the total fluorescence intensity.