构筑根孔湿地夏季浮游植物群落结构特征

Phytoplankton community structure in constructed root-channel wetlands in summer

湿地通过复杂的物理、化学、生物过程改变水质状态,而浮游植物能够快速、准确地反映环境变化并广泛应用于水质评价。2013年夏季对嘉兴市石臼漾构筑根孔湿地（运行5年）与贯泾港构筑根孔湿地（运行初期）的浮游植物群落结构进行了调查,分析了湿地内部浮游植物变化特征,识别其主要影响因素。结果表明,贯泾港湿地分布浮游植物5门70种（含变种）,石臼漾湿地浮游植物6门68种（含变种）。绿藻门是贯泾港和石臼漾湿地浮游植物种类最主要的构成类群,分别占总种类数的46%和49%。贯泾港湿地浮游植物细胞数量在1 478.43×10^4～18 544.24×10^4cells/L之间变化,均值为9 374.69×10^4cells/L,变化幅度较大;石臼漾湿地浮游植物细胞数量整体低于贯泾港湿地,在598.58×10^4～3 587.71×10^4cells/L之间变化,均值为2 526.36×10^4 cells/L。贯泾港湿地和石臼漾湿地水体水质处于β-中污型到α-中污型,整体上呈现出石臼漾湿地水质优于贯泾港湿地。研究表明,湿地不同的运行时期对浮游植物群落结构产生了影响。

Wetlands ameliorate water quality through complex physical,chemical,and biological processes,and phytoplankton can reflect environmental changes rapidly and accurately and have been widely adopted for evaluating water quality. An investigation of the phytoplankton community structure was conducted in the water bodies of the Shijiuyang and Guanjinggang constructed root-channel wetlands in summer 2013. We analyzed the variation in phytoplankton characteristics within wetlands and revealed the major factors influencing the variation. A total of 70 phytoplankton species（ including varieties） belonging to five phyla were identified in the Guanjinggang wetland during its initial operation period,whereas 68 phytoplankton species were identified in the Shijiuyang wetland belonging to six phyla after five years of operation. The main phylum was Chlorophyta in both the Guanjinggang and Shijiuyang wetlands,accounting for 46% and 49% of the total species,respectively. Phytoplankton density in the Guanjinggang wetland was from 1 478. 43 × 10^4 to 18 544. 24 × 10^4 cells / L,with relatively greater variation and mean value（ 9 374. 69 × 10^4 cells / L） than that of the Shijiuyang wetland. The Shijiuyang wetland had less phytoplankton and the algal cell density ranged from 598. 58 × 10^4 cells / L to 3 587. 71 × 10^4 cells / L（ mean：2 526. 36 × 10~4 cells / L）. Water quality of both wetlands ranged from the β-mesosaprobic to the α-mesosaprobic pattern. The Shijiuyang wetland had better water quality than the Guanjinggang wetland overall. Results suggested that operation duration affected the phytoplankton community structure in the constructed root-channel wetlands.