浅水湖泊水生态数学模型研究及应用

该文针对珠三角感潮浅水湖泊水环境模拟问题,在二维水流-污染物输移耦合数学模型基础上,结合WASP(water quality analysis simulation program)水生态数学模型原理,考虑溶解氧、氨氮、硝酸盐氮、有机氮、无机磷、有机磷、碳生化需氧量和叶绿素a等8个水质变量及其相互作用的溶解氧平衡子系统、氮循环子系统、磷循环子系统和浮游植物动力学子系统,建立了浅水湖泊水生态数学模型。通过室内实验系统模拟了珠三角某典型感潮人工湖泊外江来水营养条件对蓝藻生长的影响,确定了蓝藻生长速率等关键模型参数,并模拟了湖泊不同换水方案下叶绿素a的时空分布规律,为控制湖泊水体富营养化、预防蓝藻水华爆发提供科学依据。

Research and application of water ecology numerical model for shallow lakes

According to the numerical simulation of water quality in tidal lakes in the Pearl River Delta,a water ecology numerical model for shallow lakes is proposed based on a coupled flow-transport model and eutrophication theory of WASP (water quality analysis simulation program).The proposed model considers eight water quality indices,including dissolved oxygen (DO),ammonia nitrogen (NH3-N),nitrate nitrogen (NO3-N),organic nitrogen (ON),inorganic phosphorus (OPO4),organic phosphorus (OP),carbon biochemical oxygen demand (CBOD),and chlorophyll-a.The interactions of eight water quality indices are modeled by four subsystems of the dissolved oxygen balance,nitrogen cycle,phosphorus cycle,and phytoplankton dynamics.The proposed model is applied to an artificial lake in the Pearl River Delta.The model parameter such as the growth rate function of cyanobacteria is determined by laboratory experiments,and the spatial and temporal distribution of chlorophyll-a under different scheme of water replacement is simulated by the proposed model.Results show that the proposed method can provide evidence for the control of eutrophication in tidal lakes.