Question

1. In eutrophic waters, photosynthesis by algae? which one ?

produces carbon dioxide

produces oxygen

causes the amount of alae to decline

Answer 1

Under eutrophic conditions algae produces oxygen by photosynthesis however eutrophic conditions favour the bloom in the algal population which causes an increase in the process of respiration and decomposition which leads to an increase in the level of carbon dioxide in waters.So though at initial stage of eutrophication it seems that high algal population is causing high oxygen concentration but gradually it leads to increased carbon dioxide and death of other water organisms.