Biological Data
The A.P. Biology and Freshwater Ecology classes used in situ light/dark bottle method to determine both the gross and net primary productivity, the ability of autotrophic organisms to fix inorganic carbon in organic compounds. Since the light bottle allows both photosynthesis and respiration and the dark bottle only respiration, oxygen gain or loss from initial oxygen levels can be used to determine the extent of photosynthetic reactions and the resulting fixing of carbon. Because of low light penetration, both gross and net primary productivity fall off sharply with increasing depth, and net productivity is actually negative at greater water depths because of the dominance of respiration through decomposition and algae maintenance. This trend has been enhanced by the success of algae in the pond as it eutrophies and light availability to lower depths becomes more limited.
Other data - Fish from Anderson Pond
Video Clips of Organisms found in Anderson Pond (Note: opening videos in a new window with WinDVD4 will give the best results)
Phylum Rotifera - Rotifers are invertebrates characterized by a corona of cilia on their anterior end which is used to generate currents to direct phytoplanktonic food into their mouths. They are usually between 100um - 500um long, and some genera are able to withstanding very low concentrations of oxygen for extended periods of time.
Order Cladocera & Phylum Rotifera - The cladocerans belong to the phylum Crustacea and have the characteristic carapace that covers the thoracic and abdominal regions. They are between 0.2mm - 3.0mm long. Complex movements of the thoracic legs create currents that allow for the filter-feeding of algae and protozoa. Close inspection allows for the viewing of the dorsal heart beating to circulate body fluid through an open circulatory system. Many species can withstand low oxygen conditions.
Order Copepoda - Copepods are also crustaceans that freely swim and feed on phytoplankton in the water column. They are generally from 0.3mm - 2.0mm long. Most copepods are far more tolerant to oxygen deficiency than the cladocerans.