A Comparative Study Of Remote Sensing And Its Application In The Phycocyanin Extraction Method

At present, most of the lakes of China have shown varying degrees of eutrophication, especially the Taihu Lake, Chaohu Lake and other lakes in Yangtze River Basin. Accompanied by eutrophication, algal bloom outbreaks frequently when a serious threat to sustainable social and economic development and ecological security of the the catchment lakes. Therefore, the monitoring of eutrophic lake and the establishment of early warning and forecast about algal blooms mechanism are particularly important. In the lake water environment monitoring technology, compared with the traditional monitoring techniques, remote sensing technology for its continuous, dynamic, real-time and cyclical characteristics, showed a huge advantage. However, the evaluation and the building of remote sensing retrieval model, depends on the measured data of water quality parameters. Cause of many lakes outbreaks algal blooms mainly are cyanobacteria, the phycocyanin is indicative pigment of cyanobacteria, for eutrophic lake water, the extraction technology of phycocyanin is study few. Take the eutrophic lake Chaohu lake for example, using the cultured Microcystis aeruginosa and Chaohu water cyanobacteria as the extract objects of phycocyanin. Use filter collect the cyanobacterial cell. Use repeated freezing and thawing method by liquid nitrogen broke the cyanobacterial cell, with the extraction agent extract phycocyanin and UV-visible spectrophotometry method for the determination of phycocyanin, to compare three different buffer (Tris-HC1, Phosphate buffer, Asolectin-CHAPS) for extraction. By the comparative analysis of the absorption spectrum of phycocyanin and the concentration and the relationship between phycocyanin and chlorophyll-a to compare the three buffers. Absorption spectra show that all the characteristic absorption peak of phycocyanin are emerged at620nm. Experimental results show that, AC buffer and PBS buffer are better than the Tris-HCl buffer in extraction efficiency. AC buffer is more expensive and also more difficult to obtain and save, which make it not suitable for large-scale use. So we recommended PBS buffer as usual buffer for meeting the requirements of large-scale water quality monitoring. Furthermore, based Simis’s phycocyanin retrieval model and ASD spectrometer measured spectral data, estimating the phycocyanin in Chaohu Lake. Estimation results compared with the measured phycocyanin concentration data. The results showed that:in practice, Simis retrieval model does not apply for the region which cyanobacterial blooms appear, but the model are suitable for normal water bodies.