Research On The Detection System Used For The Concentration Of Chlorophylla In Seawater

At present, the pollution in the sea is serious, and there are Red Tides all around the world. The Red Tides which are caused by the excessive propagation of the phytoplankton not only cause a tremendous damage on economy but also threaten human's health and even the life. So, it is very important to measure the concentration of phytoplankton.There are many methods to measure the concentration of phytoplankton, and in this paper we use the fluorescence method. The exciting light with its wavelength determinate causes the chlorophyll-a to emit the fluorescence, and there is a relationship between the fluorescence and the concentration of phytoplankton, so we can get the concentration of phytoplankton by measuring the intensity of the fluorescence. Compared with other methods, it is precise, fast, with good repeatability, easy to sample, and can be used in situ in practical application.This paper introduces the research actuality, the emission process of the chlorophyll, the principle of the fluorescence method, and main factors which influence the intensity of the fluorescence. The detection system designed according to the character of the fluorescence is described in detail. The system contains two parts, one is how to emit fluorescence, and the other is how to detect the fluorescence. At the end of this paper, some experiments are carried out, and the fluorescence method is compared with the method using spectral photometer. At last, the capability of the system is discussed and some advice about how to improve the system is given.