Figure 2

Diversity of microbial communities in sediment oil agglomerates (SOAs), SOA-surrounding sands, and control sands over the 3 year time course. Incubation time is represented as days after SOA deployment. (a) Alpha-diversity is calculated based on Shannon indices and (b) the number of observed OTUs (Student’s t test: p-value = 0.015* and 0.001***).