Transcript Plankton
Life in the Ocean 1) Plankton-drifters 2) Nekton- the swimmers 3) Benthic- bottom dwellers Nekton Benthic Plankton Plankton Plankton- organisms that are at the mercy of (drift with) the currents Types of Plankton At least three classification schemes are used to categorize plankton Plankton bloom during 1997 El Nino Photosynthetic Ability 1) Photosynthetic ability • Phytoplankton- can photosynthesize2) • 2) Zooplankton- do not photosynthesize • 3) Bacterioplankton- bacteria, some photosynthesize, some do not Phytoplankton – The photosynthetic organisms that are very important in oxygen production, more so than terrestrial plants. – Diatoms and dinoflagellates dominate the larger groups – Nanophytoplankton are the most important photosynthetic organisms in the oceans Diatoms- the earth’s most abundant, successful, and efficient single-celled phytoplankton Diatoms- they possess two interlocking valves made primarily of silica, these valves contribute to biogenous sediments. Dinoflagellates – class of microscopic single celled flagellates (have whip like tail for propelling) Florentinia Cleistosphaeridium Red Tides Responsible for red tides (see assignment) Coccolithophores • Small single celled autotrophs covered with disks of calcium carbonate • In areas of high abundance they can make waters appear milky Nanoplankton (or picoplankton)very small phytoplankton (a high number of species are this kind) Zooplankton- animal members of the plankton community • These are heterotrophs which means they do not produce their own food and rely on outside sources for nutrients • These graze on the diatoms and dinoflagellates • Shrimp like animals (copepods) are the most abundant Foraminefera- planktonic amoeba like animals with a calcium based shell Extend filaments to snare food Krill Giant Jellyfish Bacterioplankton Microscopic single celled Life History 2) Life History Characteristics a) Holoplankton-entire life span is within the plankton community Most zooplankton are this type b) Meroplankton- part of the life span is within the plankton community, often larvae of the nekton and benthic organisms Planktonic mantis shrimp larvae Tube anenome Larval spiny lobster 1) Size (Table 2.1) • Femtoplankton- little known group, viroplankton fall here • Piccoplankton 0 - 0.002 mm Ultraplankton 0.002 - 0.0055 mm Nannoplankton 0.005 - 0.06 mm Microplankton 0.06 - 0.5 mm Mesoplankton 0.5 - 1.0 mm Macroplankton 1.0 mm - 1.0 cm Megaloplankton greater than 1.0 cm • The last four groups are called net plankton because they can be caught with plankton nets. • The first three groups are obtained through centrifugation, filtering, or settling of samples. Plankton nets Net is hauled slowly for a known distance behind a ship and organisms carefully removed • These scientists developed a form of SCUBA diving called "bluewater diving" in order to observe plankton directly in the field. In this form of research diving, a group of divers are attached to a small boat via a "down-line". This leaves them free to collect and observe without the danger of floating too far from the boat or sinking too deep • Researchers can now use high technology submersibles to study creatures that live in the deep sea. Plankton counters Why Collect and Study Plankton? 1)They form the bottom of the food chain in the sea and are very important in ocean food webs. In other words, the abundance of plankton directly correlates to the abundance of other marine organisms (fish, whales etc.) 2) Red tides Manta ray feeding on plankton krill Blue shark feeding on krill