Marine Biology DISL

Jennifer Estes || 2025 Session 1

Delta

Head of the bay

Mouth of the Bay

Seawater primarily enters through here

Depositional Environment

Where sediment is deposited on the bay bottom

CTD

Conductivity, Temperature, Depth

Profiles

Changes in salinity, temperature, dissolved oxygen, or other parameters as functions of depth

Hydrocast

The act of lowering, then raising a meter through the water column each time

Thermocline

A zone located beneath the surface in which a rapid decrease in temperature occurs relative to the change in depth

Pycnocline

Density gradient

Stratified

A water column that has ‘layers’

PPT or ‰

Salinity units in parts per thousand

Halocline

A sharp change in salinity with depth

Refractometer

Typical hand-held device for measuring salinity

Nomographs

Specially designed plots showing the relationship between dissolved oxygen, salinity, and temperature

Hypoxic

When DO is below 2.0mg/L

Anoxia

No oxygen, DO is 0 mg/L

Jubilees

A periodic bout or sustained period of hypoxia or anoxia

Winkler Titration

Most common chemical method to determine dissolved oxygen content of water

Polarographic Electrode

The sensor used to profile dissolved oxygen by establishing a current between a cathode and an anode

Benthic

Bay bottom

Pelagic

Water column

Plankton (general)

Microscopic organisms

Nekton

Macroscopic organisms

Infauna

Organisms that live within the sediments

Grabs and Cores

Remove a chunk of the sediments

Sleds and Dredges

Drag along sediment surface

Plankton (specific)

Free-living organisms in pelagic marine environments that are unable to swim against a current of approximately 1 knot

Phytoplankton

Category of plankton that contain chlorophyll and photosynthesize

Net Plankton

Mega-, meso-, macro-, and microplankton caught in nets

Meroplankton

Species that spend only part of their life as plankton

Holoplankton

Species that spend their whole life as plankton

Bacterioplankton

Planktonic bacteria

Viroplankton

Marine viruses

Mycoplankton

Planktonic fungi

Neuston

Organisms restricted to the air-water interface

Oceanic Plankton

Species that occur