A Comparative Study on Diversity of Algae in Coal Mine Impacted and Unimpacted Streams of Jaintia Hills, Meghalaya

The present paper deals with a comparative study on diversity of algal communities in the AMD (acid mine drainage) impacted streams with that of unimpacted streams of Jaintia Hills, Meghalaya. A total of 113 taxa were recorded from unimpacted streams belonging to six major algal groups Bacillariophyceae (56), Chlorophyceae (42), Cyanophyceae (9), Euglenophyceae 4), Chrysophyceae (1) and Rhodophyceae (1), whereas only 34 taxa were recorded from AMD impacted streams belonging to 4 groups. Bacillariophyceae (24), Chlorophyceae (4), Cyanophyceae (4), and Euglenophyceae (2). Out of 4 Chlorophyceaen members, two filamentous green algal species belonging to Ulotrichales namely Microspora and Klebsormidium were found to form thick algal mat covering the whole stream bed in the AMD streams. Other 32 members were recorded from the rocky bottom and dead leaves and twigs. Bacillariophyceae has been found to be the most dominant group and Navicula was the most dominant genus. 22 members from Bacillariophyceae 4 from Chlorophyceae, 2 from Euglenophyceae and 3 from Cyanophyceae were common in both impacted and unimpacted streams. The change in diversity could be attributed to the significant differences in pH, acidity, dissolved oxygen, free Carbon dioxide and sulphate content of the water bodies of impacted streams.