2. Marine Ecology
Group 2:
Bueno, Riomel
Cordeñera, Donna
Falcis, Mary Grace

3. Marine Ecology is the scientific study of marine-life
habitat, populations, and interactions among
organisms and the surrounding environment
including their abiotic (non-living physical and
chemical factors that affect the ability of organisms
to survive and reproduce) and biotic factors (living
things or the materials that directly or indirectly
affect an organism in its environment).
Marine ecology is a subset of the study of marine
biology and includes observations at the
biochemical, cellular, individual, and community
levels as well as the study of marine ecosystems and
the biosphere.

4. TROPHIC
STRUCTURE
TROPHIC LEVELS
All organisms in an ecosystem
can be placed in trophic levels
depending on what energy
source they rely upon and how
they provide energy for other
organisms in the food web.
With the exception of life near
hydrothermal vents in the deep
ocean, life is always dependent
directly or indirectly on the
energy from the sun.

5. ENERGY FLOW
The food chain consists of trophic levels, or the levels
within the food chain in which energy is transformed. Due
to basic principles of thermodynamics, energy is always lost
to the environment any time an organism at one trophic
level uses the energy from the trophic level below.

6. COMPONENTS OF AN ECOSYSTEM
There are four parts to every ecosystem: the abiotic
environment (e.g. geology or geography), producers (e.g.
phytoplankton), consumers (e.g. shrimp) and decomposers
(e.g. bacteria). Energy from the sun and abiotic nutrients
such as carbon dioxide or minerals are taken in by
producers and transformed into usable energy through
photosynthesis. Consumers, like herbivores, are dependent
on producers to convert sunlight, water, and carbon dioxide
into glucose, which can be then be divided through
respiration to recover the sun's energy. Carnivores are
secondary consumers if they only prey on herbivores and
tertiary consumers if they eat other carnivores.
Decomposers, the organisms responsible for decomposing
dead animal and plant matter, are able to break down
organic waste back into minerals that can be used by
producers.

7. BIOMASS
When biomass is produced through photosynthesis, the
amount can be measured in terms of primary
production.

8. NUTRITIONAL GROUPS
Organisms in the food chain are categorized into three
basic nutritional groups in reference to what kind of
carbon, energy, or electron source is utilized to make
energy. Heterotrophic organisms use organic substrates
and autotrophic organisms use inorganic substrates to
obtain carbon. The reducing equivalent source is how
organisms get electrons to reduce for biological
processes. Lithotrophic organisms utilize inorganic
compounds to get electrons and organotrophic
organisms use organic compounds to get electrons
necessary for biological processes. Phototrophic
organisms use light energy and chemotrophic
organisms, like those found near hydrothermal
vents, use energy from chemical sources.

9. BIOTIC STRUCTURE
Biotic structure describes the
way organisms interact within
an ecosystem. The opposite of
biotic is abiotic, which includes
the physical and chemical
factors present in the
environment. Every organism in
a species has a limit of
tolerance, zone of stress, and
optimum range for the abiotic
factors present in its
environment. Ecosystems can
be simplified into three basic
groups of organisms:
producers, consumers, and
decomposers. Some organisms
can be in more than one
category.

10. FOOD CHAINS AND FOOD WEBS
Food webs illustrate the relationship between animals
and what they feed on in the biotic community. Food
webs also show how material and energy is transferred
and lost within the ecosystem.

11. FOOD CHAINS
A food chain is different from a food web because it
illustrates only one energy and nutrient path in an
ecosystem. Each platform is a trophic level with one
organism that begins with one primary producer and
ends with a secondary or tertiary consumer.

12. FOOD WEBS
Food webs are more intricate than food chains and
illustrate the feeding relationships between a numbers of
organisms at different trophic levels in an ecosystem.

13. TROPHIC LEVELS
Trophic levels are the platforms in the food chain that
indicate a position for a particular organism. In a very
basic way, a trophic level will indicate whether an
organism is a foundation species, primary consumer, or
secondary consumer. Information about whether the
organism eats plants or animals can also be obtained.
Most often trophic levels are used to determine how
much energy is lost from the primary producers up to
the tertiary consumers. For each trophic level in the food
chain, energy is lost due to the laws of thermodynamics.

14. SYMBIOSIS
Symbiosis is a term most often used to describe two
organisms living in a close association that benefits both
of their survival.

15. COMPETITION
Species better adapted to their environment are able to
survive and produce offspring. In biological
terms, fitness refers to the number of offspring an
organism is able to produce (versus the most well-
known term indicating greater physical strength).

16. PREDATORS
The common definition of a predator is one that hunts
and kills other organisms for food. It could be claimed
that herbivores are predators due to some similarities in
their style of seeking and eating food.

17. THE STRUCTURES AND
ADAPTATIONS TO MARINE
LIVING
The ocean covers the majority of the planet, yet it
remains a little understood realm as scientists are
limited in the study of habitats that lack physical
boundaries and can span thousands of miles.
Each form of marine life has become adapted to a
specific niche with a relatively narrow variation in
salinity, temperature, and light. The high salt content
found in the ocean can support the large bodies of giant
squids and whales, which has allowed them to evolve
without the use of strong limbs for support.
Nevertheless, salt water exerts enormous pressure on
the air spaces of marine animals at depth (fluids like
blood are practically incompressible).

18. CHORDATE ORIGINS
Animals in the Phylum Chordata include the vertebrates
and some of the more primitive nonvertebrates like the
protochordates, lancelets, acorn worms, tunicates, and
the pterobranchs. The first vertebrates appearing in the
fossil record during the Cambrian age were animals that
resembled fishes and had respiratory gills formed by
pharyngeal gill slits located in a set of pouches. The first
purpose of the skeleton and scales were to protect the
animal, to add support to the notochord, and to keep the
brain protected. Later, a true backbone (rather than a
notochord) evolved in marine animals.

19. REPTILES
The reptiles came about as a novel group of terrestrial
animals from the amphibians. Reptiles were extremely
successful on land and quickly became the dominant
animal for the next 150 million years. When mammals
evolved, they took over the dominant position leaving
the reptiles to crawl back into the ocean. The reptiles
that survived include the snakes, turtles and lizards
many of which have changed a little so they can live
more successfully in salt-water environments.

20. MAMMALS
Marine mammals include the Order Cetacea (porpoises
and whales), the Order Carnivora (animals like
seals), and the Order (dugongs, manatees and sea
cows). Marine mammals are still warm-blooded and have
to keep the temperature of their bodies above that of
the ocean. Adaptations that have helped solve this
problem include the reduction of surface area and the
increase in internal volume, a fatty layer of blubber
under very thick skin, and a reduction in the amount of
blood going to areas in contact with the cold water.
Unlike land animals, marine mammals are also able to
dive very deep into the water without getting the bends
because as they dive down deeper they exhale instead
of inhale like we do.

21. ANIMALS WITH SHELLS
About 500 million years ago, animals with hard-shells
became prominent in the fossil record in the Phylum
Molluska. The evolution of an impenetrable shell was
obviously a very helpful trait for an animal to possess
because now mollusks are found in almost every known
environment. Animals with hard shells are protected
from predation and drying out and some can even use
their shell to float if necessary among other things.

22. EFFECTS OF POLLUTION AND
HUMAN ACTIVITIES ON THE
MARINE LIFE
Oceans constitute around 70% of the surface of earth
and are an important part of the ecological cycle. Oceans
are vast water resources and are home to millions of
plants and organisms. Unabated human-activity has
resulted in degradation of marine life and there are
several species of organisms that are on the verge of
extinction. The harmful and toxic substances that come
out of industries are dumped into oceans, putting plants
and animals to grave risks.

23. Causes of Ocean
Pollution
Marine transportation
and oil spills: Oil spills are
a major cause of ocean
pollution. Oil is spilled
mostly from oil containers
which are being transported
from one place to another
on ships. Oil spills can also
be a result of leakage from
aircraft flying over the
ocean.

24. Garbage and sewage: The
garbage and sewage that is
dumped by ships
deliberately into the oceans
is one of the biggest
contributors to ocean
pollution. Garbage and
sewage contains toxic
chemicals and these can
stay in the ocean for a long
time.

25. Acid rain: Acid rain is not
a natural phenomenon but a
result of industrial and
automobile pollution.
Poisonous gases from these
sources are released in the
environment which when
combined with rainwater
forms acid rain. Acid rain
facilitates the transfer of
harmful gases to oceans.

26. Impact of Ocean Pollution on Marine Life
Like humans, marine organisms also need oxygen for
their survival. Oxygen is present in the dissolved form
in the oceans and the toxic substances have an ability
to absorb this dissolved oxygen, thus resulting in
decrease in the oxygen levels inside the oceans.
Pollutants also stimulate the growth of certain
organisms that are harmful for marine organisms.
The contamination of ocean water with poisonous
chemicals and toxins has already killed hundreds of
thousands of marine organisms and many more are
under the threat of extinction. The chemicals also
have far-reaching effects as these interfere with the
genetic make-up of organisms and cause various
physiological changes. Because of this continuous
exposure to chemicals and toxins, around two-thirds
of marine life has been declared as 'threatened
species'.

27. ECONOMIC REGULATIONS
Ecosystems are controlled by a multitude of
factors, each influencing the other. Almost all living
organisms rely on the energy from the sun. Organisms
at the base of the food chain, such as phytoplankton and
plants, use the sun's energy directly. Organisms higher
on the food chain receive energy from the sun indirectly.
The only organisms on the planet capable of producing
energy without the sun are microorganisms called
chemoautotrophs that often live near deep sea vents
and synthesize energy through a chemical process.

28. ENERGY
There are thousands of species of primary producers in
the ocean that convert inorganic carbon into organic
compounds. phytoplankton’s are responsible for 95% of
all primary production and use energy from the sun
directly. These primary producers absorb energy from
the sun through pigments inside the chloroplasts or
through membranes in the cytoplasm of bacterial cells.

29. “There are things in life that are
yet to be discovered, mysteries to
be solved and puzzles to be put
together, but never forget to
treasure what we have now and
what we loved the most.”