Affiliation:
1. University of Vienna, Austria
Abstract
Algae encompass a phylogenetically diverse group; its members are placed in the domains Bacteria and Eukarya, in the latter dispersed in five supergroups. Contrary to common assumption, algae are found almost everywhere from aquatic to terrestrial habitats, some of them in symbiotic relationship, others thriving in harsh environments such as deserts, hot springs, or on ice. Around 45% of atmospheric oxygen is released by algae, which underlines their pivotal role in global element cycles. This high diversity is also reflected in different morphologies from microscopic single cells to parenchymatous organisms measuring several meters in size. The total species number is estimated from 70,000 to more than 10,000,000. Algae produce various valuable compounds, but this high natural potential is only marginally being used. To date, only a few taxa are commercially exploited.