Research And Simulation On Blue-green Algae Bloom In Taihu Lake

Blue-green algae,widely distributed almost all over the world,is one kind of the most ancient and primitive algae plants. A visual characteristic of the bloom is that there is a large amount of algae pellets accumulating and increasing step by step in the water body. The toxin and peculiar smell that blue-green algae releases out destroy the ecological balance and endanger human life and health directly and it is of great significance to study the mechanism of blue-green algae outbreak.With the progress of science and technology, the technologies such as integrated circuits, wireless communications, embedded computing and micro-sensor achieve rapid development and make it possible to comprise a wireless sensor network by a large number of low-cost, low power, multi-function miniature sensor. "Sensing China" put forward will simulate an unprecedented advance in WSN(wireless sensor network). In virtual Taihu lake system developed for some Supervising Department in Suzhou, the paper presents a method for the algae simulation based on wireless sensor networks and particle system theory. The basic idea of this method is to analyse the dominant factors of algae bloom, design a set of temperature and transparency measurement system online with WSN. The system is able to supply the real data of some dominant factors and guarantee the real-time data transmission by GPRS. Through analyzing the objective law of particle growth and the action forces of particles in the water,we establish mathematical models which control the growth and movements of particles. Blue-green algae in Taihu Lake has random, complex movements and growth, and it consists of a huge number of blue-green algae particles, so we use CPU and GPU to carry on the simulation of bloom in Taihu Lake in order to take full advantage of efficiency of GPU programming and its parallel processing capabilities. Practice has proved that the method can be a good simulation of the outbreak process.We construct simulation scenarios for the simulation, Catmull-Rom algorithm is used to simulate the lake bottom and a rotating sky demo is used to simulate the blue sky while adopting the approach of perturbing the texture coordinate to carry out refraction on the lake and obtaining the reflection of sky dome based on the principle of light reflection. Finally, we synthetize the scenes to realize the real-time simulation and rendering of particles and satisfy the task.