基于复杂网络同步特征的水华暴发数值模型

A numerical model of algal bloom based on the synchronization of complex networks theory

基于复杂网络的同步特征和藻类动力学生长特性,以汉江近年来水华污染的现场监测资料为例,并结合氮磷浓度、水温等实测数据构建了水华暴发的数值模型,用以描述藻类生长和水华暴发的动力学机制;同时,利用达到指定藻生物量临界值的网格数规模作为判定水域是否暴发水华以及规模大小的依据,从复杂网络同步特性的角度验证了水华暴发的临界性和全局突发性,进而揭示了水华暴发现象是水域子区域整体协同作用的结果.计算结果表明,如果达到临界值的网格数超过指定的规模,相应水域将暴发水华,且网格达到峰值状态持续的时间越长,水华污染越严重.

According to on-site observations and monitoring data,including total concentrations of nitrogen and phosphorus and water temperature,a numerical model was constructed based on characteristics of alga growth and synchronization of complex networks theory. This model could help us understand the intercorrelations of the dynamic mechanism of algal bloom and the complex evolution of algal growth in the Hanjiang river. Criteria for the evolution of an algal bloom and its scale were based on whether the grid scale reached the specified algal concentration. The criticality and the holistic emergency of the algal bloom were verified by synchronization. We demonstrate that an algal bloom is the result of synergic action of the whole valley＇s water system. Our results show that as soon as the grids exceed the specified scale in the numerical model,algal bloom pollution would occurs in the corresponding valley water system,and the duration of the peak states in the grid is proportional to the scale of the algal bloom.