基于ELCOM-CAEDYM模型的太湖蓝藻水华早期预测探讨

The discussion of the early forecasting of cyanobacteria bloom in the Lake Taihu based on ELCOM-CAEDYM model

结合太湖蓝藻水华形成的"四阶段理论",基于澳大利亚西澳大学水研究中心开发的ELCOM-CAEDYM耦合模型框架构建了太湖水华蓝藻生态动力学模型,对蓝藻水华的形成进行模拟,分析了太湖蓝藻水华早期预测的可行性.结果表明:该模型在较长时间尺度上对春季复苏阶段及生长上浮阶段蓝藻水华的形成模拟效果较好,蓝藻生物量模拟值与站点调查值的误差变化范围在1.0%～70.4%,平均误差为28.0%,与MODIS卫星反演值的误差变化范围在3.8%～83.9%,平均误差40.5%;但越冬阶段蓝藻生物量模拟输出值与站点调查值的误差变化范围在3.0%～143.6%,平均误差为40.1%,与MODIS卫星反演值的误差变化范围在9.7%～118.4%,平均误差为48.8%,表明模型对蓝藻越冬过程模拟能力还不强,应在蓝藻越冬机制模拟计算方面进一步改进,以满足蓝藻水华早期预测的需要.

An ecological dynamic model for cyanobacteria bloom in Taihu Lake was structwed based on the theory of ＂four phases of cyanobacteria bloom development＂ and the coupling model of ELCOM - CAEDYM developed by Centre for Water Research, University of Western Australia. The cyanobactetia bloom development was modeled and the possibility for early forecast of cyanobacteria bloom in Taihu Lake was discussed. The model outputs met well with the cyanobacteria biomass in a large temporal scale coveting the phases of anabiosis, growth and upfloat. The differences between modeled data and field-determined （or surveyed） ones varied in the range 1.0%-70.4% with a mean of 28.0%. The differences between modeled data and the inferred ones from MODIS satellite imagery varied in the range 3.8%-83.9% with a mean of 40.5%. However, the model outputs weakly reflected the cyanobacteria biomass in the phase of overwintering, the differences ranged from 3.0% to 143.6% with a mean of 40.1% between modeling data and the field-determined ones, and from 9.7% to 118.4% with a mean of 48.8% between the modeled data and the inferred ones from MODIS satellite imagery. The simulation of cyanobactetia overwintering need to be improved to better serve the early forecast of eyanobaeteria bloom.