巢湖水华蓝藻原位生长率的时空变化及其环境影响因子

原位生长率是研究藻类生长、衰亡、种群演变、生产力估算,以及藻类对环境变化响应的重要指标,针对水华蓝藻原位生长率的测定,目前还缺乏成熟可靠的手段.本研究利用改进的原位培养法,根据培养前后藻蓝素浓度的变化,对巢湖东、中、西3个湖区水华蓝藻的原位生长率进行周年调查.结果 表明,巢湖水华蓝藻的原位生长率变化范围在-1.16～0...

Spatial-temporal variations of the in-situ growth rate of bloom-forming cyanobacteria and their environmental factors in Lake Chaohu, China

In-situ growth rate is an important parameter for algae to study their growth, death, population variation, productivity and response to environmental changes. Currently, there is a lack of mature and accurate method to determine the in-situ growth rate of bloom-forming cyanobacteria. In this study, an improved in-situ incubation method base on the change of phycocyanin were used to investigate the annual net in-situ growth rate of bloom-forming cyanobacteria in the eastern, central and western lake areas of Lake Chaohu. The results showed that the net in-situ growth rate of bloom-forming cyanobacteria ranged from -1.16 to 0.69 d^-1. The growth rates in the surface layer were higher than those in the middle layer, and those in the bottom layer were the lowest and negative in most months. In terms of spatial distribution, the growth rates from high to low were the eastern, central and western lake areas. The growth rates were the highest in spring (April to June) and the lowest in winter (January to February). Spearman correlation analysis showed that growth rate was positively correlated with dissolved total phosphorus (DTP) and temperature, which indicates that DTP and temperature are the key environmental factors affecting the in-situ growth rate of bloom-forming cyanobacteria in Lake Chaohu.