基于光照和温度环境条件下杜氏盐藻的生长数学模型构建

Growth Mathematical Model Construction of Dunaliella Salina based on the Environmental Conditions of Light and Temperature

杜氏盐藻作为重要的经济微藻,在能源和制药等行业取得应用,其规模养殖工艺已经成熟,但其工艺的可调控和稳定性较差,限制其产业化发展。研究采用实验与数学模型相结合方式,添加光照和温度变量因子,将Logistic微分方程进行改进,构建盐藻生长数学模型。通过实验研究不同光照和温度条件对盐藻生长速率和生物量的影响,结果表明光照强度和温度对杜氏盐藻的生物量积累和生长速率影响都较为明显,且两者对盐藻生长的影响方式分别符合光照模型和温度动力学模型。采用Matlab粒子群优化算法根据实验数据对改进的Logistic模型参数进行优化,校准了8个模型参数,并对模型进行预测验证,获得具有一定精度和可预测性的盐藻生长阶段数学模型。根据模型模拟,盐藻的生物量在一定范围内都随着光照强度的增强而增加,随着温度增加先增长后降低,确定了盐藻生长的最佳光照条件为108μmol/m^(2)s^(2),最佳温度条件为305.15 K。

As an important economical microalgae,Dunaliella salina has achieved applications in the energy and pharmaceutical industries,and its large-scale culture process has been matured.But its process is less adjustable and stable,which limits its industrialisation development.In this study,the variables of light and temperature were added to improve the logistic differential equation,and the growth mathematical model of D.salina was constructed by the combination of experiments and mathematical models.The results of different light intensity and temperature conditions on the effects of growth rate and biomass,showed that the effects of two enviromental conditons on the algae growth were both obvious,and both influence ways the algae growth conformed to the light and temperature kinetic models,respectively.The Matlab particle swarm optimisation algorithm was used to optimise the parameters of the improved logistic model based on the experimental data.Eight model parameters were calibrated,the model was validated for prediction and a growth mathematical model of D.salina was obtained with certain accuracy and predictability.According to the model simulation,the biomass of the algae increased with the increase of light intensity in a certain range,and increased firstly and then decreased with the increase of temperature.The optimal enviromental conditions for the algae growth were determined to be the light intensity of 108μmol/m^(2)s^(2)and the temperature of 305.15 K.