Summary
International Symposium on Nonlinear Theory and its Applications
2005
Session Number:4-2-5
Session:
Number:4-2-5-4
Study on a Water Environmental Problem From a Viewpoint of a Nonlinear Complex System
Tomoaki Itayama, Akihiro Koide, Tomoyuki Yasukawa, Hitoshi Shiku, Tomoyasu Matsue, Yuhei Inamori,
pp.142-145
Publication Date:2005/10/18
Online ISSN:2188-5079
Summary:
Toxic cyanobacteria grows in many eutrophicated lakes and causes many acute environmental problems. We analyzed the phenomena of vast proliferation of toxic cyanobacteria in an eutrophicated lake using a nonlinear model equation of population dynamics determined. In the nonlinear model equation of cyanobacterial we used, we focused on the interaction of rise of the pH and pressure from the zooplankton. The rise of pH is according to the proliferation of cyanobacteria. This equation was numerically solved and the vast proliferation of cyanobacteria was determined as a bifurcation phenomenon. However, it is not sufficient to only use simple and conceptual model analysises to tackle real environmental problems. To deal with the real complex system of natural environments or natural ecosystems, we are developing on a Lab-on-a-Chip device to rapidly measure the properties of many species of plankton and microbes in real water ecosystems. The combinatorial methodology as a powerful tool for a complex system analysis can be introduced into environmental studies by use of this new device that we are developing. Both the simplified analysis and the combinatorial method are very important for solving real environmental problems.