Gong Dan-Dan, Liu De-Fu, Zhang Jia-Lei, Yang Zheng-Jian, Zhu Xiao-Ming, Tan Qian-Ru
Engineering Research Center of Eco-environment in Three Gorges Reservoir Region, Ministry of Education, College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang 443002, China.
Key Laboratory of Ecological Remediation of Lakes and Rivers and Algal Utilization of Hubei Province, School of Civil Architecture and Environmental Engineering, Hubei University of Technology, Wuhan 430068, China.
Huan Jing Ke Xue. 2016 Jun 8;37(6):2149-2157. doi: 10.13227/j.hjkx.2016.06.018.
In order to study the mechanism of the habitat disturbance of reservoir on algae blooms, some interior control experiments about the feature of algal diversity and the succession of community structure under different temperature disturbance cycle but the same amplitude condition were conducted, based on the intermediate disturbance hypothesis and combined with algal community habitat selection theory and ecological functional groups of algae. The results showed that:① the intermediate disturbance would accelerate the growth of algae and increase their diversity. Under the gradient of the intermediate disturbance group Δ22℃/48h, the diversity of phytoplankton was the highest, and the biomass reached the maximum, however, without absolute dominant algal species. While in the high frequency disturbance group Δ22℃/24h the biodiversity was relatively lower, but the algae biomass was reduced. ② the periodical change of temperature had obvious influence on the succession of the phytoplankton community, and the dominant species also presented certain differences. The succession of the algal advantageous function group followed the basic rule of X()→J()→S() or X (), and the community structure also presented a trend that the C/CR type algae took advantage and the superiority was gradually replaced by R type algae. When the high temperature disturbance was frequent, the R type algae (S) was distinctly ascendant. During the experiment, the community structure was given priority to the C/R strategy algae with no or low disturbance. However, the coexistence of algae with different growth strategies was evident in group Δ22℃/48h. Meanwhile, the S strategy algae (L) resistant to high temperature stress began to emerge.
为研究水库生境扰动对水华的作用机制,基于中度干扰假说,结合藻类群落生境选择理论及藻类生态功能群,开展了不同温度干扰周期但幅度相同条件下藻类多样性特征及群落结构演替的室内对照实验。结果表明:①中度干扰会促进藻类生长并增加其多样性。在中度干扰组Δ22℃/48h梯度下,浮游植物多样性最高,生物量达到最大,但无绝对优势藻种。而在高频干扰组Δ22℃/24h中生物多样性相对较低,藻类生物量降低。②温度的周期性变化对浮游植物群落演替有明显影响,优势种也呈现一定差异。藻类优势功能群的演替遵循X()→J()→S()或X()的基本规律,群落结构也呈现出C/CR型藻类占优且优势逐渐被R型藻类取代的趋势。高温干扰频繁时,R型藻类(S)明显占优。实验期间,无干扰或低干扰时群落结构以C/R策略藻类为主。但在Δ22℃/48h组中不同生长策略的藻类共存明显。同时,耐高温胁迫的S策略藻类(L)开始出现。