Phytoplankton Function Groups And Their Spatial And Temporal Succession Characteristics In Hongfeng Reservoir And Baihua Reservoir, Guizhou Province

Hongfeng Reservoir and Baihua Reservoir is located at Guizhou Province. Different from traditional approach of community identification, this study identified functional groups of phytoplankton to understand the distribution patterns of the two reservoir. Phytoplankton and water samples were taken in dry period(November 2012), level period(April 2013) and wet period(July 2013). And in order to explore the effect of the river on the reservoir of phytoplankton functional group composition change and water quality, in mid-august to late-September 2013 and late march to late may 2014 took water and Phytoplankton sample from the surface of Maixi River estuary in Baihua Reservoir everyday and took the same sample in different depth everyweek, and explore the long-term succession characteristics of Hongfeng Reservoir phytoplankton functional groups by collecting and analyzing phytoplankton data of Hongfeng Reservoir.The results showed: there existed 102 genera and 7 phyla phytoplankton in Hongfeng Reservoir, 109 genera and 7 phyla phytoplankton in Baihua Reservoir, in Baihua,green algae had the largest number of species, followed by cyanobacteria. Phytoplankton community structure were characterized by dry period Cyclotella sp. as the dominant species(genus), Pseudanabaena limnetica in wet period as the dominant species; Phytoplankton abundance composition showed distinct seasonal change and vertical variation,specific performanced dry season < level period <wet period, Phytoplankton abundance of the surface layer to the bottom layer showed a gradually decreasing trend.Results suggested that there were 25 functional groups of phytoplankton in Hongfeng reservoir and 22 functional groups of phytoplankton in Baihua Reservoir. Frequency analysis found that functional group P、 B、D、J、Lo、MP,LM in the two reservoirs in the frequency distribution was greater than 50%,they were a common functional groups.The seasonal changes among 3 sampling points were generally the same. of phytoplankton functional groups in each sampling point decreased in the dry period and increased in the level period and wet period.The dominant functional groups had obvious distribution patterns: Hongfeng reservoir, J/B/P in the dry period, S1/J/B/F in the level period and S1/ D/J in the wet period. For vertical change: in Hongfeng Reservoir, phytoplankton functional group changed in two sample points JJW and HW as 6m was the cut-off point, functional groups of Baihua Reservoir easily changed in 10-15 m depth and bottom.The strategy of phytoplankton growth followed the law: Hongfeng Reservoir, CR in dry period�'R/CR/CS in level period �'R in wet period, Baihua Reservoir, R/CR in dry period�'CR/C in level period �'R in wet period, advantage phytoplankton functional groups could fully grown with ideal conditions of material supply and energy input, the phytoplankton functional groups showed more tolerance than other groups with the increased of energy restriction.The functional groups P, B, J, S1 played a dominant role in the seasonal succession of two reservoirs. The habitat characteristics of main functional groups are adapted to the eutrophication water, codon P habitat template: eutrophic epilimnia, codon S1 habitat template: turbid mixed environments, codon J habitat template: shallow, mixed, highly enriched systems(including many low-gradient rivers), codon B habitat template: mesotrophic small- and medium-sized lakes with species sensitive to the onset of stratification. Besides, the analysis of environmental factors showed that temperature was the most important factor which influence the spatial and temporal distribution of phytoplankton functional groups. Nitrogen and phosphorus were the second important driving factors for he spatial and temporal distribution of phytoplankton functional groups. It could be concluded that Hongfeng and Baihua Reservoir in a state of meso-eutrophic by the correlation of phytoplankton functional groups and aquatic environment.Phytoplankton of Maixi River estuary in Baihua Reservoir had high abundance in the two periods and a increasing trend with temperature, Maixi River estuary had low water transparency and high mixing degree, its phytoplankton had no obvious vertical stratification.A total of 23 functional groups of phytoplankton were identified, S1 is absolute advantage function group for a long time. It could be concluded that Maixi River in a state of eutrophic by the correlation of phytoplankton functional groups and aquatic environment, Baihua Reservoir functional groups composition and water quality is affected by it.From 1980 to now, the succession characteristics of Hongfeng Resevoir dominat functional groups composition is: functional group M(Microcystis) and H1(Aphanijomenon) transformed into S1(Pseudanabaena limnetica) which accounts for absolute advantage. The change of nutrient conditions is drivers of succession.