Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
4398582 | Journal of Great Lakes Research | 2013 | 8 Pages |
Abstract
The composition and both the temporal and spatial distribution of phytoplankton were studied in Lake Poyang; samples were collected every 3 months from January 2009 to October 2011 at 15 sites. The phytoplankton community was found to belong to seven groups, with Bacillariophyta dominating. No significant difference was observed in the phytoplankton community structure at any of the sites (p = 0.2371), except one site; however, the structure was significantly different with regard to annual and seasonal trends (p = 0.0001 and p < 0.0001, respectively). Aulacoseira granulata, Synedra acus, Fragilaria virescens, and Cryptomonas erosa were the main contributors to the dissimilarity in temporal distribution. Although the nutrient concentrations for 3 years combined were relatively high (mean total nitrogen was 1.719 mg Lâ 1 and mean total phosphorus was 0.090 mg Lâ 1), phytoplankton biomass was low (mean total biomass of 0.203 mg Lâ 1). The underwater light condition, as indicated by the Secchi depth, was shown to be the principal limiting factor in regulating the growth of phytoplankton, and the transparency coincided with biomass variation on a seasonal level. The effect of nutrients on phytoplankton may be concealed by the water level, which varied over a wide range among different seasons. However, the annual trend for the biomass was associated with the nutrient concentration, which increased yearly and initiated the development of phytoplankton. The biomass is high in the south and low in the north, which may be the result of greater underwater light climate and high nutrient concentrations in the southern area.
Related Topics
Physical Sciences and Engineering
Earth and Planetary Sciences
Earth and Planetary Sciences (General)
Authors
Zhaoshi Wu, Yongjiu Cai, Xia Liu, Cai Ping Xu, Yuwei Chen, Lu Zhang,