Transcript Introduction to Marine Life

Introduction to Marine
Ecosystems
Ocean Ecosystem
• An ecosystem is a level of organization
that includes living things and their
environment
• Living things cannot exist without their
environment
• Most of our planet is covered by the ocean
or marine ecosystem
Structure and Function of an
Ecosystem
What the ecosystem is made up of and how it works are linked and
influence each other…
STRUCTURE
Amount of non living
materials
FUNCTION
Interactions between living
things
How living conditions vary
with time and space
Characteristics of living things
Cycling
LAND vs OCEAN
• Ocean is wetter than land
– Materials can be dissolved in ocean water
– Gametes can be dispersed more easily
– Harder for smaller things to move through
water
• Ocean is more vast than land
– Harder to find mates and food
• Ocean is more supportive than land
– Body structure will be different than land
animals
• Living in aquatic environment will shape
biology and adaptations of marine life
ABIOTIC and BIOTIC FX
Physical or non-living parts of the
environment that influence living things are
called abiotic factors
examples:
Living factors which influence living things
are called biotic factors
examples:
Abiotic Factors in the Ocean
• Inorganic nutrients like: C,N,H,P,S,Fe,Si
• Motion in the ocean: upwelling, currents,
tides
• Dissolved materials like gases and salts
• Climate: temperature, light, pressure
• Variations in time and space
Inorganic Nutrients
• Most of the ocean is nutrient poor
• Only 10 percent of the surface
area of the global ocean supports
half the world’s fisheries
• Nitrogen, phosphorus, iron and
silica are like fertilizer for ocean
plants
Source of nutrients
– Runoff from land, animal feces and
decomposition
– all this material sinks out of reach
Surface nutrients get used up (by plants to
make plant tissue) they become a limiting
factor for the growth of new plants which
are only found in surface waters
Nutrients are returned to surface waters by a
special type of current called 'upwelling'
Other Ways Nutrients are
Replaced
• Winter storms, after the thermocline has
disappeared
• Deep water currents can be deflected by
underwater island chains
Motion-Upwelling
• Upwelling is a vertical current,
bringing nutrient rich water from the
bottom to the surface.
• Upwelling areas support a lot of life
• Occur off the west coasts of
continents or in the middle of the
equatorial parts of oceans.
• Upwelling is often seasonal
www.coolclassroom.org/cool.../upwellingtutorial.html
Why Upwelling Happens
• Earth's rotation and strong
seasonal winds push surface
water away from coasts
• Deep water rises on the edges
of continents to replace it.
uwgb.edu
Motion-Tides
• Alternating rise and fall of sea level
– Produced by gravitational attraction to moon
and sun as well as the rotation of the Earth
• Tides produce strong currents up to 5 m/s
•
• http://www.oc.nps.edu/nom/day1/partc.html
Motion-Tides
• Area on the beach exposed between high
and low tide is intertidal zone
• Organisms must deal with breaking
waves, exposure above water, and daily
variations in water temperature and
salinity
• Adaptations, such as firm attachment to
rocks and shells to hold in moisture, to
deal with these conditions.
http://geosci.sfsu.edu/courses/geol102/ex9.html
Marine Life and Tides
• Some marine life time their feeding
and reproduction to the high or low
tide cycle
• Horseshoe crabs come ashore to
mate on the night of a high tide in
May
• Eggs hatch 2 wks later on a high tide
and are washed into the ocean
Motion-Currents
Motion-Currents
• Ocean currents move heat around the globe
and affect local climate
• Driven by atmospheric winds and Earth’s
rotation
• Found in upper 400m and speeds around 1 m/s
• Pollution, marine life and food can be stuck in
currents and moved around the globe
Dissolved Materials
• Seawater is fresh water plus dissolved
materials like salts, minerals and gases
• Amount of material dissolved depends on
temperature of water
Dissolved Gases
• Oxygen, carbon dioxide and nitrogen
• Dissolve into the ocean from the
atmosphere through wave action also
released at the surface back into
atmosphere
• Dissolve better in cold water
• Animal life and plant life can change
the chemistry of ocean gases
Dissolved Gases
• Plants photosynthesize, animals respire,
bacteria decompose
• Plants use CO2 and produce O2
• Animals use O2 and produce CO2
• Decomposition uses O2 and produces CO2
• Around 500 m water runs out of
oxygen
–Bacteria and other animals are
using it during decomposition
and respiration
–No photosynthesis at this depth
• Animals in this region and lower
have large gills, modified
hemoglobin or are inactive
Gas Exchange and Carbon Cycle
• Oceans absorb and store large amounts of
CO2
– Contain about 50 X the amount found in the
atmosphere
• biological pump -some of the absorbed
CO2 is used in the food web by
phytoplankton, or used to make shells and
then consumed and pooped out
• gas is trapped in the deep ocean
(sequestered) until brought to surface by
currents
Ocean Acidification
• CO2 is changed to carbonic acid as it
dissolves in seawater
– More CO2 dissolving, more acidic ocean is
becoming
– 30% increase in acidity since IR
• Marine life that produce calcium carbonate
shells are negatively impacted by
increasing acidity (coral, clams, mussels,
oysters, some algae)
• The photos below show what happens to a
pteropod’s shell when placed in sea water
with pH and carbonate levels projected for
the year 2100. The shell slowly dissolves
after 45 days. Photo credit: Used with
permission, National Geographic Images
Dissolved Salts
• Dissolved salts/ minerals come from land
and underwater volcanic activity
• Average salinity is 35 parts per thousand
• Salts change water density and
differences in density contribute to the
creation of water masses and deep ocean
circulation
• Thermohaline circulation, also called the
Global Ocean Conveyor, moves water
between the deep and surface ocean
worldwide
Figure 1: Relative proportions of dissolved salts in seawater. (Source: PhysicalGeogr
• Thermohaline circulation, also called the
Global Ocean Conveyor, moves water
between the deep and surface ocean
worldwide.
Click on image for full size
Image courtesy Argonne National
Laboratory
• Image courtesy Argonne National Laboratory
Marine vertebrates control internal salt and water
concentration by osmoregulation
http://marinebio.org/oceans/ocean-chemistry.asp
Climate: temperature, light, pressure
• Ocean conditions vary with depth and with
latitude
http://climate.lanl.gov/
http://geosci.sfsu.edu/courses/geol102/ex9
.html
•
http://geosci.sfsu.edu/courses/geol102/ex9.html
Animal Adaptations and Pressure
• Ocean life has adapted to deep
ocean and 1000x our pressure with
lightweight skeletons, little
musculature, and reduced metabolic,
growth and reproductive rates.
• Diving mammals have rib cages that
collapse and expand in result to
changing pressure
Yelloweye rockfish with barotrauma. Shows esophagus protruding from mouth and
bulging eyes (exophthalmia). (Credit: Image courtesy of Oregon State University)
Water Depth vs Light
• Photosynthetic organisms use light to make
sugars.
• Sunlit area (top 100 meters) contains 90%
of marine life
• Colors of penetrate thru water differently
– Red light filters out first and blue light
goes the furthest
– Red animals are essentially invisible in
deep waters
blog.hotelclub.com
cdnn.info
driftline.wordpress.com
Animal Adaptations and Temperature
• Average ocean temp is 3  C
• Colder temps reduce the metabolic rate
• In very cold waters fish have a special
protein like antifreeze to keep tissues from
freezing
• Lighter colored animals stay cooler than
darker colored animals and are found in
warmer waters
• Some marine life have thick layers of fat to
insulate their bodies
Variations in Time and Space
• Characteristics of ocean water change
with depth and season
• Many marine organisms migrate daily or
seasonally because of these variations
Openlibrary.org
Biotic Factors in the Ocean
• Characteristics of living things
• Diversity: How many and what types of
things live there
• Interactions between living things:
competition, predation, symbiosis
Characteristics of Life
•
•
•
•
•
•
Made of cells
Getting energy
Growth and development
Reproducing
Respond to environment
Maintaining homeostasis
Naturalseasponge.com
Diversity of Living Things
• Systematics- Groups organisms for
classification and study
• Describes the evolutionary relationships
between orgs
• Earliest life forms evolved in the ocean
Diversity of Living Things
• Two main division are based on cell structure
• Prokaryotes – Kingdom Moneran / bacteria
group
– Lack a nucleus and membrane bound organelles
• Eukaryotes- All other kingdoms
– Have a nucleus and membrane bound
organelles
http://io.uwinnipeg.ca/~simmons/1116/images/bactloco.gif
http://www.biol.tsukuba.ac.jp/~inouye/ino/etc/dinoflagellates.jpg
Diversity of Living Things
• The broadest category of life starts at the top
and includes one or more of the succeeding
categories
• Domain of life
– Kingdom
• Phylum
–Class
»Order
Family
Genus and species
Diversity of Living Things
• Every organism has a two part name
unique to itself-Binomial Nomenclature
– Can only interbreed with other organisms of
its kind
• Genus species or Genus species
– Prevents confusion if a species is known by
many common names
• Example: Common dolphin is known as
Delphinus delphis
Interaction Between Living
Things
• Competition
– A habitat can only support a fixed number of
individuals
• Limits on space, nutrients, mates etc..
– May result in extinction of a species or niche
segregation ( both species become more
specialized and can then coexist)
– Winners and losers change based on varoius
factors like stability of ecosystem, predation
Interaction Between Living
Things
• Predation- one organism hunts, kills and
eats another organism
– Over time prey evolve adaptations to avoid
predation which prey must adapt to as well
– Arms race between two organisms
• Important in culling weak or sick animals
from the population
• Some are keystone species which
promote the diversity of species in a
habitat
eyesonafrica.net
Interactions between living
things
• Symbiosis- living together of unlike
organisms
– Mutualistic- Both species benefit from the
relationship
• Remora and shark: remora gets food scraps,
shark has parasites removed
michaelmcfadyenscuba.info
– Commensal- one species benefits and the
other has no benefit or harm
• Hermit crab and a snail (shell)
myfishtanks.info
– Parasitic- one species benefits but the other is
harmed
• Female and male anglerfish
http://www.ma
rineparasites.c
om/gallery.htm
l#44
s15.zetaboards.com