PHYTOPLANKTON COMMUNITY IN THE SMALL SUBSIDED LAKES AROUND HUAINAN COAL MINE SUBSIDENCE AREAS

To investigate phytoplankton community and aquatic environmental factors, three small lakes at PXPJ site, PXGQ site and PXXQ site in Huainan Panxie coal mine subsidence area were chosen over the four seasons from 2013 to 2014. A total of 131 species of phytoplankton were identified, which belong to 7 phyla, 9 classes, 25 orders, 34 families and 70 genera. The primary phytoplankton species were Cyanophyta, Chlorophyta, and Bacillariophyta. Chlorophyta, Cyanophyta, and Bacillariophyta had 59, 24 and 22 species, respectively accounting for 45.0%, 18.3% and 16.8% of the total specie, respectively. The predominant species at PXPJ site are Chlorophyta, Bacillariophyta and Cryptophyta, ranging from 77.5% to 90.5% to the total algal cells. The predominant species at PXGQ in summer and autumn is Cyanophyta accounting for 61.5% and 46.2%, respectively. Cyanophyta is the major one at PXXQ site but distributes differently over season - 94.6% ratio in spring, 74.7% in summer, and 81.8% in autumn, respectively. The abundance, diversity and uniformity of the three small subsided lakes could be influenced by the the difference of eco-hydrological environment conditions. Canonical correlation analysis (CCA) showed that light, temperature, nutrient content and ratios (TN/TP) were the key factors affecting the different characteristics of phytoplankton community in subsided lakes.