Analysis Of Algal Growth Mechanism And Construction Of Its Multi-agent Model

The study of algae growth is an important subject in the field of water environment.There are many factors affecting algae growth and the influence mechanism is more complex.Because there are many factors affecting the growth of algae and the influence mechanism is more complex under under natural conditions,there will be lake flow,wind and waves and other factors,which further affect our study on the growth mechanism of algae.Therefore,the ecosystem of "water-sediment-Vallisneria natans" was constructed in the laboratory,and the changes of algae growth and water quality indexes were continuously observed.Variance analysis and correlation analysis were used to analyze the variation characteristics of water quality indicators,and partial least square regression analysis was used to evaluate the factors affecting algae growth.On the basis of experimental research,the dynamic simulation model of algae growth is constructed by using multi-agent modeling method.The findings of the study are as follows:(1)In this study,variance analysis and correlation analysis were used to analyze the change characteristics of water quality index and its relationship with algae growth.Based on the advantages of Partial Least Squares Regression(PLS)in solving multicollinearity and explaining the importance of independent variables to dependent variables,chlorophyll a was used as the characterization of algae growth,and partial least squares regression analysis was used to evaluate the main influencing factors of algae growth in simulated algae lakes and simulated grass lakes respectively.The results showed that the factors closely related to algae growth in simulated algal lakes were pH,TDS,DO,conductivity and ORP.According to the regression coefficient,chlorophyll a concentration decreased with the increase of conductivity,and increase with the increase of pH,TDS,DO and ORP.The factors closely related to algae growth in simulated grass lakes were turbidity,temperature,ammonia nitrogen,TP,ORP and N/P.According to the regression coefficient,chlorophyll a concentration decreased with the increase of ORP and N/P,and increase with the increase of turbidity,water temperature,TP and ammonia nitrogen.(2)Based on the theory and method of multi-agent modeling,the whole system is divided into multi-agent layer,environment layer and interaction layer.In the multi-agent system,the algae agent,the Vallisneria natans agent and the sediment agent are constructed,and the properties and behavior rules of the three kinds of agents are reasonably set on the basis of previous research results.The algal growth and its important environmental elements,such as light,temperature,nutritional salts and so on,were constructed.In the interaction layer,the interaction between agent and other agents and between agent and the environment was realized by accessing the internal variables of the agents.(3)Based on the NetLogo platform,the three-dimensional environment space of algae growth is constructed,and the foreground interface and background program are designed for simulation experiment,and the multi-agent model of algal growth is realized.By setting different environmental variables and the number of subjects,the dynamic evolution of algae growth in different environments is simulated,and the growth and evolution process of algae is observed from the micro level and macro level respectively,so as to prove the validity and rationality of the model.