南方湿热环境下基于铁假说理论研究富铁湖泊藻华生消过程和机理

According to Leibig Law of the Minimum，trace metal elements are the crucial limiting nutrients of algal blooms in eutrophic lakes. The studies of effects of trace metal elements on algal blooms are hot issues and very difficult, because of the complicated relations between them. On basis of Iron Hypothesis, this project will study forming mechanisms and influencing factors of algal blooms of rich-iron-lakes under hygrothermal environment of Southern China. It will confirm the types and critical concentrations of algal available iron, by studying the influencing mechanisms of different types and concentrations of iron on algal biomass, growth velocity, Chlorophyll a, generation time, etc. And through researches on relationships between changing processes of portions and concentrations of iron types and developing of algal population and forming of preponderant algae, it will comfirm the effects of different iron sources on forming trends of preponderant algae. It also will explain the coupling impacts of macro-components and iron on algal blooms, with the changing rules of iron、carbon and nitrogen during the process of algae absorbing iron. The project tries to analysis the dynamic evolution of algal blooms from the aspect of trace metal elements, explore the driving mechanisms on algal blooms by iron sources. Those expected achievements can support to solve the issue of limiting factors of algal blooms, make progress to predicating methods, control harmful algal blooms, and protect the safety of drinking water.

按利贝格最小值定律，富营养湖泊中微量金属元素成为藻华爆发的关键限制营养元素，但由于微量金属元素对藻华的影响表现为"限制、促进"相互交替的复杂关系，相关研究是藻华预警技术的研究热点和难点问题。课题基于铁假说理论，系统研究南方湿热环境下富铁水体中藻华的生消过程和影响机制。通过研究铁的不同形态和浓度对藻类生物量、比生长速率、叶绿素含量、世代时间的影响，确定藻可利用铁的类型和临界浓度；考察铁的形态比例、浓度变化过程和藻种群分布演变、优势藻确立过程之间的协变关系，判断铁源对藻华优势藻的形成趋势影响；研究藻吸收铁过程中碳、氮等常量元素的浓度变化规律，阐释常量元素和铁对藻华生消过程的耦合影响。课题致力于从微量金属营养关键限制作用的角度剖析藻华生消的动态演变过程，探究水中铁源与藻华生消之间的驱动关系，为解决藻华控制关键因素问题，完善藻华预警技术，控制有害藻华，保障饮用水供水安全提供新的理论和技术依据。

按利贝格最小值定律，富营养湖泊中微量金属元素成为藻华爆发的关键限制营养元素，但由于微量金属元素对藻华的影响表现为“限制、促进”相互交替的复杂关系，相关研究是藻华预警技术的研究热点和难点问题。课题基于铁假说理论，以南方湿热环境下富铁水体中常见的蓝藻、绿藻、硅藻为藻源，采用人工培养方法，系统的研究离子态铁（Fe2+、Fe3+）及络合态铁（柠檬酸铁铵、EDTA-Fe 、腐殖酸铁、草酸铁）对藻类增殖及优势藻形成过程的影响及机制。通过研究铁的不同形态和浓度对藻类增殖过程的影响，确定藻可利用铁的类型和临界浓度；考察铁的形态、浓度变化过程对藻种群分布演变的协变关系，判断铁源对藻华优势藻的形成趋势影响；研究藻吸收铁过程中磷、氮常量元素对藻类增殖的影响，阐释常量元素和铁对藻华生消过程的交互作用。课题致力于从微量金属营养关键限制作用的角度剖析藻华生消的动态演变过程，探究水中铁源与藻华之间的驱动关系，为解决藻华控制关键因素问题，完善藻华预警技术，控制有害藻华，保障饮用水供水安全提供新的理论和技术依据。