title: Analysis of algal bloom risk with uncertainties in lakes by integrating self-organizing map and fuzzy information theory.
abstract: Algal blooms are a serious problem in waters, which damage aquatic ecosystems and threaten drinking water safety. However, the outbreak mechanism of algal blooms is very complex with great uncertainty, especially for large water bodies where environmental conditions have obvious variation in both space and time. This study developed an innovative method which integrated a self-organizing map (SOM) and fuzzy information diffusion theory to comprehensively analyze algal bloom risks with uncertainties. The Lake Taihu was taken as study case and the long-term (2004-2010) on-site monitoring data were used. The results showed that algal blooms in Taihu Lake were classified into four categories and exhibited obvious spatial-temporal patterns. The lake was mainly characterized by moderate bloom but had high uncertainty, whereas severe blooms with low uncertainty were observed in the northwest part of the lake. The study gives insight on the spatial-temporal dynamics of algal blooms, and should help government and decision-makers outline policies and practices on bloom monitoring and prevention. The developed method provides a promising approach to estimate algal bloom risks under uncertainties.
authors.affiliation: RCEES, Chinese Academy of Sciences, Shuangqinglu 18, Beijing 10085, China; China Three Gorges University, Daxuelu 8, Yichang 443002, China; CEER, Nanjing Hydraulics Research Institute, Guangzhoulu 223, Nanjing 210029, China. Electronic address: qchen@rcees.ac.cn.
authors.forename: Qiuwen
authors.initials: Q
authors.lastname: Chen
authors.affiliation: RCEES, Chinese Academy of Sciences, Shuangqinglu 18, Beijing 10085, China.
authors.forename: Han
authors.initials: H
authors.lastname: Rui
authors.affiliation: RCEES, Chinese Academy of Sciences, Shuangqinglu 18, Beijing 10085, China.
authors.forename: Weifeng
authors.initials: W
authors.lastname: Li
authors.affiliation: RCEES, Chinese Academy of Sciences, Shuangqinglu 18, Beijing 10085, China.
authors.forename: Yanhui
authors.initials: Y
authors.lastname: Zhang
mesh_terms: D017753:Ecosystem; D004784:Environmental Monitoring / Q000379:methods*; D005068:Eutrophication; D017143:Fuzzy Logic; D007257:Information Theory; D060106:Lakes / Q000737:chemistry; D015233:Models, Statistical; D035501:Uncertainty; D014876:Water Pollution / Q000706:statistics & numerical data*
keywords: Algal bloom; Fuzzy information theory; Risk uncertainty; SOM; Taihu Lake