510 likes | 1.11k Views
Marine Ecology. Ecology is the study of the inter-relationships between the physical and biological aspects of the environment. It is the study of how organisms adapt to their environment and in turn alter it. 9-1. Ocean Habitats.
E N D
Ecology is the study of the inter-relationships between the physical and biological aspects of the environment. It is the study of how organisms adapt to their environment and in turn alter it.
9-1 Ocean Habitats There are two major marine provinces: the benthonic (bottom) and the pelagic (water column). • The benthonic environment is divided by depth into the: Intertidal zone, Sublittoral zone, Bathyal zone, Abyssal zone, and the Hadal zone • The pelagic environment is divided into the Neritic Zone and the Oceanic Zone
9-1 Ocean Habitats The ocean can also be divided into zones based upon depth of light penetration. • The photic zone is the depth where light is sufficient for photosynthesis. • The dysphotic zone is where illumination is too weak for photosynthesis. • The aphotic zone receives no light from the surface because it is all absorbed by the water above.
9-2 Classification of Organisms In 1735 Linnaeus developed the taxonomic classification used in zoology. • The categories are from largest to smallest: Kingdom, Phylum, Class, Order, Family, Genus and Species. • The name of a species consists of the genus name combined with a trivial name. • The genus name begins with a capital.
9-2 Classification of Organisms The five major kingdoms in the ocean are: Monera, Protista, Fungi, Metaphyta and Metazoa. • Monera are the bacteria and blue-green algae. • Protista are single-celled organisms with a nucleus. • Fungi are abundant in the intertidal zone and are important in decomposition. • Metaphyta are the plants that grow attached to the sea floor. • Metazoa include all multicellular animals in the ocean.
9-3 Classification of Lifestyle Marine organisms can also be classified by lifestyle. • Plankton are the organisms which float in the water and have no ability to propel themselves against a current. • They can be divided into phytoplankton (plants) and zooplankton (animals). • Nekton are active swimmers and include marine fish, reptiles, mammals, birds and others. • Benthos are the organisms which live on the bottom (epifauna) or within the bottom sediments (infauna). • Some organisms cross from one lifestyle to another during their life, being pelagic early in life and benthonic later.
9-4 Basic Ecology Environmental factors in the marine environment include: temperature, salinity, pressure, nutrients, dissolved gases, currents, light, suspended sediments, substrate (bottom material), river inflow, tides and waves. • Ecosystem is the total environment including the biota (all living organisms) and non-living physical and chemical aspects. • Temperature can control distribution, degree of activity and reproduction of an organism. • Salinity can control the distribution of organisms and force them to migrate in response to changes in salinity.
9-4 Basic Ecology • Hydrostatic pressure is the pressures exerted by a column of water surrounding an organism.
9-5 Selective Adaptive Strategies More than 90% of marine plants are algae and most are unicellular and microscopic. • To photosynthesize (produce organic material from inorganic matter and sunlight) plants must remain within the photic zone. • Diatoms are single cells enclosed in a siliceous frustrule (shell) that is shaped as a pillbox. • Dinoflagellates are single cells with two whip-like tails (flagella).
9-5 Selective Adaptive Strategies Zooplankton include the copepods and foraminifera. • Copepods are small herbivores (plant-eating organisms) that filter diatoms from the water. • Foraminifera are single-celled, microscopic organisms which build shells of calcium carbonate.
9-5 Selective Adaptive Strategies The morphology of fish has evolved to allow them to move through the water easily. • The fish’s body must overcome three types of drag (resistance): Surface drag, Form drag, and Turbulent drag. • Speed is dependent upon body length, beat frequency, and the aspect ratio of the caudal fin. • Aspect ratio is the ratio of the square of the caudal fin height to caudal fin area: AR = (Caudal Fin Height)2/Caudal Fin Area • There are three basic body forms, each adapted to a different life style. • There is a strong correlation between predation success and body form.
9-5 Selective Adaptive Strategies Intertidal benthonic communities generally display vertical zonation that parallels sea level. • Zonation reflects the amount of time the area is submerged and the ability of the organism to survive the stress of exposure. • Benthonic communities also vary in response to substrate (bottom material).