挺水植物对湖泊水质数值模拟过程的影响

Influence on Emerged Plant in the Process of Numerical Simulation About Lake Water Quality

将environmental fluids dynamics code(EFDC)模型和CE-QUAL-ICM模型相结合,建立了内蒙古乌梁素海富营养化模型.在建模过程中,考虑挺水植物分布情况及其密度、高度、直径等形态指标,并将考虑挺水植物影响与未考虑挺水植物影响的氮磷模拟过程进行计算、对比、分析.结果表明,考虑挺水植物影响的氮磷浓度模拟值与实测值变化趋势基本一致,而未考虑挺水植物影响的氮磷浓度模拟值未能反映实测值的变化趋势,可见,湖泊挺水植物的存在对氮磷浓度的迁移转化起着关键的作用.同时,在模拟过程中明显提高了运算效率和模拟精度,表明考虑挺水植物影响的富营养化模型能够较好地反映湖区内某位置氮磷浓度的动态模拟结果,能够为湖泊管理部门提供一定的参考.

An eutrophication model on Wuliangsuhai Lake in Inner Mongolia is established through combining the environmental fluids dynamics code model with CE-QUAL-ICM model.In this model,the distribution of emergent plants,density,height,diameter and other morphological indicators to be considered.At the same time,nitrogen and phosphorus are calculated,compared and analyzed by whether to consider the impact of emergent plants to nitrogen and phosphorus in the simulation process.The result shows that the trend of simulated and measured values on nitrogen and phosphorus by considering the impact of emergent plants is consistent;however simulated values can’t reflect the measured values if not to considering the impact of emergent plants.It can clearly be seen that emergent plants plays a key role in migration and transformation of nitrogen and phosphorus,which improve the efficiency and simulation accuracy.Overall eutrophication model considering the impact of emergent plants can better reflect dynamic simulation results on the concentration of nitrogen and phosphorus in the region of a lake;also can provide some reference to lake management.