||Basic Research in the Aquatic Environment: Effects of Eutrophication on Phytoplankton Populations and Selected Species of Aquatic Vascular Plants.
Mulliga, Hugh F. ;
||Cornell Univ., Ithaca, N.Y. Water Resources and Marine Sciences Center.
||DI-14-01-0001-1533; OWRR-B-011-NY; 06835,; B-011-NY(1)
Water pollution control ;
Weed control ;
Aquatic weeds ;
Biological productivity ;
Water chemistry ;
Phophorus inorganic acids ;
Nitrogen cycle ;
||Most EPA libraries have a fiche copy filed under the call number shown. Check with individual libraries about paper copy.
Changes in nutrient concentration are reflected in changes in plant populations. Planktonic algae and benthic plants are in direct competition. An increase in one componenet usually is accompanied by a decline in the population of the other. Continuous fertilization with N and P above the level of .05 mg N/l and .005 mg P/l leads to a dominance in the summer phytoplankton population. A cessation of enrichment causes the plant population to return to natural levels. The concentrations of P-PO4 remain high and it appears that nitrogen is the more limiting of the two elements under natural conditions. Prolonging the cover of the ice has the same consequence as adding additional nitrogen to the water. Although aquatic environments can recover rapidly from enrichment and re-establish near normal vegetation conditions, they are liable to be easily disturbed by unusual natural occurrences such as prolonged ice cover due to exceptionally cold winters.