The Groups and Distribution Characteristics of Fine Organic Autotrophic Particles in a Subtropical Reservoir Using Flow Cytometry

Flow cytometry was applied in the study of the groups and spatial distribution characteristics of the fine particles in Bantou—Shidou Reservoir, a subtropical reservoir in Xiamen,China. The fine organic autotrophic particles in reservoir could be divided into four groups conspicuously: R2 group in the smallest size with much phycoerythrin but little chlorophyll; R1 and R4 groups in relatively large size: R1 group with certain phycoerythrin and chlorophyll, while R4 group with no phycoerythrin but much chlorophyll; R3 group in the largest size with certain phycoerythrin and a large amount of chlorophyll. All the sampling stations in Shidou ( upper reaches) and Bantou ( lower reaches) reservoirs contain maximum R1 group with quantity between 35.41-46.85×106 ind/L and 23.39-43.02×106 ind/L; and minimum R3 group with quantity between 0.20-0.58×106 ind/L and 0.22-0.78×106 ind/L. The quantity of fine organic autotrophic particles is larger than that of organic azoic particles and inorganic particles. In view of the spatial distribution, R1 and R3 groups distribute unevenly in Shidou reservoir, while R2 and R4 groups change a little in quantity in different sampling stations and distribute much evenly. Moreover, in Bantou reservoir, R1, R2 and R3 groups distribute unevenly in the sampling stations, while R4 group distributes relatively evenly. The fast and multi-parameter detection capacity of Flow cytometry provides a much effective mean for the research on water fine organic autotrophic particles.