代亮亮,张云,李双双,刘瑶,李根保.不同营养水平下沉水植物的抑藻效应[J].环境科学学报,2019,39(6):1801-1807
不同营养水平下沉水植物的抑藻效应
- Inhibition of algae growth by submerged macrophyte at different nutrient levels
- 基金项目：国家水体污染控制与治理科技重大专项（No.2013ZX07102-005）
- 代亮亮
- 1. 中国科学院水生生物研究所淡水生态与生物技术国家重点实验室, 武汉 430072;2. 贵州省生物研究所, 贵阳 550000
- 张云
- 中国科学院水生生物研究所淡水生态与生物技术国家重点实验室, 武汉 430072
- 李双双
- 河北工程大学能源与环境工程学院, 邯郸 056038
- 刘瑶
- 中国科学院水生生物研究所淡水生态与生物技术国家重点实验室, 武汉 430072
- 李根保
- 中国科学院水生生物研究所淡水生态与生物技术国家重点实验室, 武汉 430072
- 摘要：控制水体的营养盐浓度，尤其是磷浓度，可以控制藻类水华的发生.然而，经济成本很高.相对藻类而言，沉水植物对水体营养盐升高敏感性更低，且沉水植物的存在可以改变藻类的群落结构和生长速率.为探讨沉水植物在营养盐与蓝藻水华控制关系中的作用，本研究探讨了有无水生植物存在下，不同营养盐浓度（磷浓度分别为0.025、0.05、0.1 mg·L-1，对应地表水Ⅲ~Ⅴ类）下蓝藻水华暴发（chlorophyll-a >10 μg·L-1）的频率、强度和持续时间.结果表明，初始藻浓度为5 μg·L-1和10 μg·L-1情况下，3种磷浓度下都会发生水华，磷浓度的升高会导致蓝藻水华暴发的强度和持续时间增加.然而，在加入水生植物金鱼藻后，初始藻浓度为5 μg·L-1的条件下，没有形成水华.初始藻浓度为10 μg·L-1的条件下，各处理组在实验初始时会形成短暂水华，之后，各处理组的叶绿素a浓度均低于10 μg·L-1，显示蓝藻生长受到抑制.因此，沉水植物存在情况下，在营养盐较高的水体，蓝藻水华也不会发生.
- Abstract：It is expensive to control the occurrence of algae blooms by lowering nutrient concentration of aquatic environment, especially for phosphorus. Compared with algae, submerged macrophyte is insensitive to the increase of nutrient concentration. Most importantly, submerged macrophyte can change the community structure and growth rate of algae. In order to examine the role of submerged macrophyte in the nutrient and control of cyanobacterial blooms, we studied the effects of submerged macrophyte on the frequency, intensity and persistent period of cyanobacteria blooms (chlorophyll-a >10 μg·L-1) at different phosphorus levels (0.025, 0.05, 0.1 mg·L-1, corresponding to surface water classes Ⅲ~Ⅴ). The results demonstrate that cyanobacteria blooms occurred at all the three concentrations of phosphorus at initial algae concentration of both 5 and 10 μg·L-1. The increase of phosphorus concentration led to higher intensity and longer period of cyanobacteria blooms. After submerged macrophyte Ceratophyllum demersum was added, there was no algae bloom at initial algae concentration of 5 μg·L-1 whereas transient algae blooms occurred in all groups at initial algae concentration of 10 μg·L-1. The chlorophyll-a concentration of each groups was lower than 10 μg·L-1, indicating the growth of cyanobacteria was suppressed by submerged macrophyte. Therefore, the cyanobacterial blooms will not occur in the presence of submerged macrophyte, even in the high nutrient concentration in water body.
