The Under Secretary shall conduct research and modeling on the effect of ocean circulation on carbon dioxide uptake from the atmosphere in response to intentional carbon dioxide removal from the ocean. (7) Aquatic biomass cultivation (A) In general The Under Secretary shall research management best practices and phenotype selection for and use of aquatic macroalgae biomass production optimized for carbon dioxide removal, including limited-scale experiments at sea, designed and monitored to avoid impacts beyond the zone of the experiment. (B) Collaboration The Under Secretary shall carry out the activities described in subparagraph (A) in collaboration with the Assistant Secretary for Energy Efficiency and Renewable Energy of the Department of Energy. (C) Risk considerations The Under Secretary shall take all feasible and prudent measures to minimize risk of economic, environmental, and social harm caused by invasive species. (8) Applied alkalinity modification techniques (A) In general The Under Secretary shall conduct limited-scale experiments on alkalinity enhancement techniques at sea, designed and monitored to avoid impacts beyond the zone of the experiment. (B) Collaboration The Under Secretary shall carry out the activities described in subparagraph (A) in collaboration with the Director of the National Science Foundation. (9) Seawater carbon extraction The Under Secretary shall conduct research and modeling on electrochemical seawater extraction, including process design and locations for minimizing resource requirements, downstream chemical and biological impacts, and storage or utilization methods. (10) Ocean fertilization fundamental research (A) In general The Under Secretary shall conduct fundamental research and modeling on the impacts and effectiveness of ocean iron fertilization and nitrogen and phosphorous fertilization research. (B) Collaboration The Under Secretary shall carry out the activities described in subparagraph (A) in collaboration with the Director of the National Science Foundation