太湖附泥藻类时空分布及与环境因子的关系

为探讨太湖附泥藻类时空分析及与N、P等环境因子之间的关系，在不同季节采取太湖不同湖区表层沉积物，采用常规理化分析方法测定环境中的氮、磷含量及其他理化指标，利用高效液相色谱技术(HPLC)分析附泥藻类光合色素叶绿素a(Chl.a)、叶绿素b(Chl.b)、岩藻黄素(Fuco)及玉米黄素(Zea)含量。结果表明：太湖水体及表层沉积物N、P浓度空间差异明显，水体中TN、TP及总溶解性磷均表现为梅梁湾>贡湖湾>胥口湾，且空间差异显著(P<0.05),而胥口湾表层沉积物中TP及Fe-P含量显著低于梅梁湾及贡湖湾(P<0.05)。太湖附泥藻类生物量(Chl.a)及3种特征色素含量存在显著的时空差异。从空间上看，Chl.a最高值出现在贡湖湾，其值为(12.79±3.69)μg/g,最低值出现在胥口湾，其值为(2.46±1.14)μg/g。在秋季及夏季，贡湖湾附泥藻类Chl.a及3种特征色素含量高于梅梁湾，梅梁湾又高于胥口湾；在春季，梅梁湾附泥藻类Chl.a高于贡湖湾及胥口湾。从季节上看，附泥藻类Chl.a与特征色素Chl.b变化一致，梅梁湾与胥口湾在春季较高，夏季和秋季相对较...

TEMPORAL-SPATIAL DISTRIBUTION OF EPIPELIC ALGAE AND ITS RELATIONSHIP WITH ENVIRONMENTAL FACTORS IN THE TAIHU LAKE

To understand the environmental variables responsible for regulating epipelic algal community composition and biomass in the surface sediment, habitat-linked heterogeneity in algal taxon-specific pigmentschlorophyll a(Chl.a), chlorophyll b(Chl.b), fucoxanthin(Fuco), zeaxanthin(Zea)] in surface sediment were investigated in the Lake Taihu by using high-performance liquid chromatography in different seasons. At the same time, the concentrations of nitrogen and phosphorus and other physical and chemical indexes in the environment were determined by conventional methods. The result showed that total nitrogen, total phosphorus and dissolved total phosphorus concentrations in the water body varied significantly in space (P<0.05) and were in an order of Meiliang bay>Gonghu bay>Xukou bay. In addition, the concentrations of TP and iron-bound phosphorus (Fe-P) from surface sediments in Xukou bay were significantly lower than those in Meiliang bay and Gonghu bay (P<0.05). The epipelic algal biomass in the surface sediment was the highest in Gonghu bay with a value of (12.79±3.69) μg Chl.a/g, while the value of (2.46±1.14) μg Chl.a/g was the lowest in Xukou bay. Algal biomass in the surface sediment varied in an order of Gonghu bay>Meiliang bay>Xukou bay in autumn and summer, and in an order of Meiliang bay>Gonghu bay>Xukou bay in spring. In Xukou bay and Meiliang bay, algal biomass and Chl.b in the surface sediment was higher in spring and lower in summer and autumn, while in Gonghu bay, algal biomass in the surface sediment was high in autumn, followed by summer and spring. Based on pigment ratios of Chl.b (Fuco, Zea) to Chl.a, the algal community was dominated by diatom, followed by cyanobacteria in the surface sediments of Lake Taihu. The results of redundancy analysis (RDA) showed that the phosphorus in the surface sediment, especially the concentration of inorganic phosphorus, was the major environmental factor affecting the development of epipelic algae. The results can provide references for further understanding the ecological functions of epipelic algae and eutrophication control in the Taihu Lake.