skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Crop recovery of sup 15 N from microalgae grown in simulated inorganic-wastewater medium

Journal Article · · Journal of Environmental Science and Health, Part A: Environmental Science and Engineering; (USA)
;  [1]
  1. Alabama A and M Univ., Normal (USA)

A greenhouse experiment was carried out using a Decatur silt loam soil to assess the availability and recovery of algal nitrogen (labeled) which was previously grown in simulated inorganic-wastewater medium by grain sorghum. Dried green or blue-green algal biomass providing 175, 350 and 525 mg labeled N/kg of soil was used as sources of nitrogen. Application of 175, 350 and 525 mg N/Kg of soil as algal biomass resulted in the release of 73.2, 126.7 and 181.6 mg N for green and 85.9, 147.6 and 183.3 mg N for blue-green algal biomass, respectively, via mineralization over a 6-week period. These values correspond to 35 to 42% of total N applied as green and 35 to 49% of total N applied as blue-green algal biomass. Grain sorghum plants assimilated 25 to 34% of total N applied as green algae and 24 to 45% as blue-green algae during 6 weeks of growth. The application of above mentioned rates increased the shoots yield by 94, 82, and 65% for green algae and 88, 61, and 61% for blue-green algae, respectively. No significant increase was observed for the application of algal biomass at a rate higher than 175 mg N/kg of soil. Total N uptake by grain sorghum increased significantly due to the addition of algal biomass to the soil. About 58 to 65% of total green algal N and 51 to 65% of total blue-green algal N remained in the soil. Six to 12% of the total N applied as green algae and 4 to 11% as blue-green algae biomass was unaccounted for.

OSTI ID:
5086116
Journal Information:
Journal of Environmental Science and Health, Part A: Environmental Science and Engineering; (USA), Vol. 23:8; ISSN 0360-1226
Country of Publication:
United States
Language:
English