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This content will become publicly available on February 21, 2019

Title: Heterogeneity in nitrogen sources enhances productivity and nutrient use efficiency in algal polycultures

Algae hold much promise as a potential feedstock for biofuels and other products, but scaling up biomass production remains challenging. Here, we hypothesized that multispecies assemblages, or polycultures, could improve crop yield when grown in media with mixed nitrogen sources, as found in wastewater. We grew mono- and poly- cultures of algae in four distinct growth media that differed in the form (i.e. nitrate, ammonium, urea, plus a mixture of all three), but not the concentration of nitrogen. We found that mean biomass productivity was positively correlated with algal species richness, and that this relationship was strongest in mixed nitrogen media (on average 88% greater biomass production in 5-species polycultures than in monocultures in mixed nitrogen treatment). We also found that the relationship between nutrient use efficiency and species richness was positive across nitrogen treatments, but greatest in mixed nitrogen media. While polycultures outperformed the most productive monoculture only 0-14% of the time in this experiment, they outperformed the average monoculture 26-52% of the time. Our results suggest that algal polycultures have the potential to be highly productive, and can be effective in recycling nutrients and treating wastewater, offering a sustainable and cost-effective solution for biofuel production.
ORCiD logo [1] ;  [2] ; ORCiD logo [1] ; ORCiD logo [1]
  1. Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Environmental Sciences Division
  2. Univ. of California, San Diego, CA (United States)
Publication Date:
Grant/Contract Number:
Accepted Manuscript
Journal Name:
Environmental Science and Technology
Additional Journal Information:
Journal Volume: 52; Journal Issue: 6; Journal ID: ISSN 0013-936X
American Chemical Society (ACS)
Research Org:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org:
USDOE Office of Energy Efficiency and Renewable Energy (EERE), Bioenergy Technologies Office (EE-3B)
Country of Publication:
United States
09 BIOMASS FUELS; Algae; biofuel; diversity; polyculture; productivity
OSTI Identifier: