FIG 1.
Bicultures outperform monocultures in three measures of bio-oil production. Bicultures, on average, yield greater algal biomass (A), fatty acid methyl ester as a weight percentage of the algal biomass (B), and total estimated mass of fatty acids (C). (D) Bicultures outperform monocultures when simultaneously considering quantity and quality of algal biomass (nested linear model on Euclidean distance to optimum: F1,34 = 2.9, P < 0.01). The “optimum” is the top rank of each metric observed in the study. As illustrated with the multifunctionality threshold approach, 43% of bicultures versus 25% of monocultures fall within the upper quadrant, indicating higher than average biomass yield and quality, via FAME percentage of biomass. Numbers indicate species identities: 1, Chlorella sorokiniana; 2, Closteriopsis acicularis; 3, Cosmarium turpinii; 4, Pandorina charkowiensis; 5, Scenedesmus acuminatus; 6, Selenastrum capricornutum; 7, Staurastrum punctulatum; 8, Tetraedron minutum.