zones of the ocean and coastline (littoral or intertidal zones)

name the 5 zones of the ocean from surface level to deepest level (including meters)

epipelagic (0-200m)

mesopelagic (200-1,000m)

bathypelagic (1,000-4,000m)

abyssopelagic (4,000-6,000m)

hadopelagic (6,000-seafloor)

which zones of the ocean make up the deep sea?

bathypelagic

abyssopelagic

hadopelagic

what are the zones of the ocean divided on?

divided based on light penetration and depth

describe the epipelagic zone

• AKA the photic zone

• contains most light

• contains planktonic organism

• separated into two zones

describe the neritic epipelagic zone

over coastline, near shore

describe the oceanic epipelagic zone

beyond continental shelf

describe the mesopelagic zone

• AKA twilight zone

• light slowly degrades 200m-1,000m where it becomes completely absent

• organisms have specialized adaptations here

in which zones do trenches occur in

hadopelagic zone

describe the deep sea

• the largest habitat on planet

• animals have are small, reduced eyes, hermaphroditic, some are bioluminescence

define an intertidal zone

area of land between high tide and low tide

define a continental shelf

shallow part of the continental margin

• gently sloping

• covered in sediments

define a continental slope

begins at the shelf break (slope abruptly gets steeper) and descends down to the deep sea

define a continental rise

where the sediment from the slope collect and form a more gradual decline

define a abyssal plain

a very gentle slope less than 1 degree toward the mid-ocean ridge

define a mid-ocean ridge

an underwater mountain range, formed by plate tectonics

what is used to map the seafloor?

side scan sonar

type of sonar that transmits sound pulses and the time interval between emission and return of pulse is recorded

describe benthic environments

• low availability of food

• no light (no photosynthesis)

• falling remains of dead orgainsm (whale falls)

• low temp (0-2 celsius)

• high pressure

what did Dr Robert Ballard do?

in 1977 he did research a long Galapagos Rift and noticed temp spikes in data

discovered hydrothermal vents

what was launch ALVIN

• HOV (human occupied vehicle)

• launched to research vents

where are hydrothermal vents located?

in divergent centers, within mid-ocean ridges

describe how hydrothermal vents are formed

cold water seeps into the crust and is geothermically heated (dissolves minerals from rocks, turning it black), the superheated water then escape the crust through a fissure above

these vents are hot, low in oxygen, and rich in metals and hydrogen sulfide

the chemicals contained from these vents are the basis for chemosynthesis

what are the three types of hydrothermal vents?

black smokers, white smokers, and seeps

characterized by different physical, chemical factors (minerals, temp, and flow)

describe a black smoker

• hottest

• darkest plumes

• high in sulfur

• can form chimneys (vents) up to 18 stories tall

describe a white smoker

• rich in barium, calcium, and silicon (so they are lightly colored)

• cooler plumes

• smaller chimneys

describe seeps

• coolest and weakest flow

• the sometimes shimmer due to difference in water temp

• can sometimes bubble due to presence of gases

define isostasy

means weighing the same

• buoyant properties of layers of rocks due to density and thickness

• explains why there are shallower seas above a continental plate than over an oceanic plate

what does the water depth of a continental shelf depend on?

• isostatic changes in land height

• changes in sea level

define the principle of isostatsy

if the crust in higher, then it is thicker/less dense

if the crust is lower, then it is thinner/more dense

which is more dense: continental crust or oceanic crust?

the oceanic crust is more dense (contains basalt) and the continental crust is less dense (contains granite)

define weathering

the breaking down of rocks

• due to exposure to atmosphere

• little movement of particles involved

describe chemical weathering

chemical composition changes through exposure to water/oxygen

describe physical weathering

broken into small pieces without changing chemical composition (temp change)

• constant heating and cooling of rocks weaken structure, breaks apart

describe organic (biological) weathering

living organisms complete weathering process

ex: lichen release special compounds that beak down rock, aiding production of soil

define erosion

the movement and transportation of broken down material by natural agents to new locations

describe ice erosion

glaciers move over land, break rock, and carry them to new location

describe gravity erosion

ex: cliff rock fall; gravity helps move rock from cliff edge to ocean below

describe wind erosion

strong breeze picks up sediment, carries it to new location

describe water erosion

ex: river runoff carrying material to new location

define deposition

the delivery of particles in a new location

define sedimentation

the deposition of suspended particles from water; left there to accumulate

• forms deltas Δ or fan shaped structure

define the littoral zone

the area where land meets sea

what impacts the nature of littoral zones

• shape of the shore

• wave action and erosion

• the substrate that makes up the shore

• the organisms that live there

define a rocky shore

any shoreline that has a rocky substrate but may vary in slope and composition of rocks

describe what can be found at a rocky shore

• boulders, stones, pebbles

• granite or igneous rocks (resistant to weathering)

• sandstone (easily broken down)

• very steep cliffs to horizontal flat rocks

• rock pools

describe some characteristics of a rocky shore

• most exposed type of shore

• most resistant to erosion

  • very little sedimentation due to speed of water coming in

• largest boulders at top of shore

• HIGH biodiversity

• stable substrate - large rocks and algae

describe the biodiversity of a rocky shore

• high biodiversity

• substrate provides many places for animals to live

what are the environmental factors that influence rocky shores?

• desiccation (extreme drying) - species near tip of shore exposed to air for long periods

• temp

• wave action

• light intensity

• aspect (N, E, S, W)

• slope

• nature of substrate

describe the formation of sandy shores

by the erosion of sandstone and sedimentation of sand particles by waves

describes some characteristics of sandy shores

• LOW biodiversity

• erosion of sandstone

• deposition of sand by sea - bc of wave action

• slope gradually toward sea

• VERY unstable - wind easily can remove fine sand that makes up shore

describe the biodiversity of sandy shores

• no shelter for organisms at the surface so they have to burrow to survive

• organisms have to adapt to environment

LOW BIODIVERSITY

describe a muddy shore

• least exposed to erosion and weathering due to little to no wave action

• allows for the deposition of silt particles

• little slope and makes mud flats

what are the three types of muddy shores?

estuaries, deltas, mangroves

describe an estuary

• form in semi enclosed body of water where fresh and saltwater meet (BRACKISH)

• water is very murky as the slow flow of water allows for particles to settle

describe the formation of a delta

• form at the mouth of a river where it meets the sea, river carries suspended sediment until it reaches a sea

describe how deltas use sedimentation

• the flow rate decreases and sediments begin to settle at bottom of river

• sediments deposit and accumulate into a fan shaped structure

• over time the delta will form tributary channels of river

define a mangrove

trees, shrubs that live in tropical/subtropical saline environments between latitudes 25 N and 25 S

form woodland habitats

describe the conditions of a mangrove area

• grow in saltwater with a large tidal range where deposition is more frequent than erosion due to calmer waters with reduced wave action

• temp of region needs to be mild to warm year round

• will grow best in areas with health coral reefs offshore due to protection provided by reefs

what are mangroves adapted to?

• wide range of salinity

• low oxygen concentrations

what are pneumatophores?

root like structures that obtain oxygen directly from air

describe the root systems of mangroves

extensive root systems

• trap particles suspended in water

• filters water

• reduce water flow

• increases deposition of sediments

• dissipates wave energy

• protects coastal area from erosion