2002 phytoplankton community composition and cyanobacterial toxins in Lake Champlain, U.S.A

摘要

Lake Champlain is the sixth largest lake in the United States, after the five Great Lakes, with a total surface area ～ 1100 km~2, volume of 2.58 x 10~(10)m~3, length of 200 km and maximum width of 21 km. This deep (maximum depth 122 m), cold water lake is located at the headwaters of the Richelieu River approximately 100 km south of Montreal, Canada bordering the U.S. states of Vermont and New York. While much useful information exists about zoo-plankton communities in Lake Champlain less is known about phytoplankton communities in the lake (Carling et al. 2004, Myer Gruendling 1979, Shambaugh et al. 1999). Previous research has demonstrated the presence, and sometimes prevalence of cyanobacteria, primarily Anabaena spp., in Lake Champlain waters over the past 80+ years (Myer Gruendling 1979). However, little is known about the lakewide distribution of these organisms and, until recently (Boyer et al. 2004), the occurrence of cyanobacterial toxins had not been described. One common toxin-producing genus, Micro-cystis, can represent up to 50 of total algal biomass in some nutrient rich lakes (Wehr Sheath 2003) and produces hepatotoxic peptides called micro-cystins that inhibit zooplankton and can affect other animals. Other potentially toxic species commonly found in Lake Champlain produce neurotoxins such as anatoxin-a from localized blooms (Yang et al. 2001, Boyer et al. 2004).