Food chain and food web

1. Marine and freshwater Ecology:
Understanding the Complexities of
Food chains and food Webs
Prepared By: Amani Alsharidah
University Number: 441203711
1443-2021

2. CONTENTS
Introduction Food chain
Food web Marine and
Freshwater fish
Promoting Biodiversity
Artificial reefs
In Saudi Arabia

3. Introduction
• Organisms interact with their community and
environment.
• And because the large number of species life in
the same area or different area. We will have a lot
of interaction between them.
• Our Knowledge of these interaction is limited.

4. Empirical and theoretical studies
divide it to
Simple Complex
Food chain Food web

5. • Food chain is the series of organisms of an ecosystem which
the food and energy present in it and passes with each member.
• A food chain consists of three Trophic Levels.
Food chain

6. Food chain divide to:
In this chain, energy and nutrients
move from plants to the herbivores
then to carnivores or omnivores.
1.The grazing food chain
2. Detrital food chain
• In this chain, its starts with dead
organic matter which is eaten by
animals then to other animals...
• A large amount of energy flows
through this chain.

7. Difference between grazing and detritus food chain
Helps in fixing inorganic nutrients
Take up energy from the detritus,
ensuring maximum utilization and
minimum wastage
Detritivores (decomposers)
Detritus
Fixes inorganic nutrients
Adds energy into the ecosystem
Sun
Green Plant ( producer)
Grazing
Remains of detritus
Begin with
Energy Source
Importance

8. Trophic Levels
Organisms in food chains are grouped into categories
called trophic levels.
First trophic level
1. Producers
Second, third, and
fourth trophic levels
2. Consumers
3. Decomposers

10. 1. Producers (Autotrophs)
• They are the first level of every food chain.
• Autotrophs are usually plants or one-celled
organisms.
• Nearly all autotrophs use a process called
photosynthesis to create Glucose from
sunlight, carbon dioxide, and water.

11. Type of Producers
Most familiar Type
Plants
Tiny organism
Phytoplankton
Larger form of its called
seaweed
Algae
Some type of it.
Bacteria

12. 2. Consumers
The second trophic level consists of
organisms that eat the producers.

13. Consumer
Turtles, Crustaceans,
Sea snails, and many
types of Fishes
Top predators, also
called apex predators,
eat other consumers.
Eat the herbivores
Eat the secondary consumers.
There may be more levels of
consumers before a chain
finally reaches its top predator.
Primary
herbivores
Tertiary
Secondary
Top

14. Depend on what the
consumers eat it can be: Animals eat only
Carnivores
Omnivores
Eat both plants and animals

15. 3. Decomposers
Detritivores and decomposers are the final part of
food chains
Detritivores are organisms that eat non-living plant
and animal remains.

16. The important of decomposers
They turn organic wastes into inorganic materials.
Decomposers complete the cycle of life, returning
nutrients to the soil or oceans for use by autotrophs.
Decomposers like fungi and bacteria complete the
food chain.
This starts a whole new food chain.

17. Aquatic food chain
Producers
1. Phytoplankton
Primary Consumers
Provide food for small fish
2. Zooplankton
3. Small fish
Secondary Consumers
Provide food for large fish
4. Large fish
Tertiary consumers an
animal on the third
trophic level

18. • It is an important ecological concept consist of a number
of food chains meshed together.
• Food web offers an important tool for investigating the
ecological interactions that define energy flows and
predator-prey relationship
Food web

19. Importance of the study of food webs
● Show us how energy flows through an ecosystem.
● Understand how toxins and pollutants become concentrated
within a particular ecosystem. (bioaccumulation)
● Study and explain how the diversity of species is related to
how they fit within the overall food dynamic.
● They may also reveal critical information about the
relationships between invasive species and those native to
a particular ecosystem.

20. Trophic Levels in a Food Web
The Same as the food chain
Who Can talk about it
?

22. • Energy enters a community when plants
and algae trap light energy during
photosynthesis.
• They change the light energy into chemical
energy in glucose, which then moves
through the community as different
organisms eat each other.
• Some energy is stored through fossilisation,
while most of it is lost through heat
dissipating into the environment.
Energy Flow

23. Keep our ocean clean

24. Types of food webs
1. Energy Flow
2.Fossil
3. Functional

25. It is depict the
relationships between organisms in
an ecosystem by quantifying and
showing the energy flow between
organisms.
1. Energy flow food webs

26. In a fossil food web, scientists attempt
to reconstruct the relationships
between species based on available
evidence from the fossil record.
2. Fossil Food Webs

27. It depict the
relationships between organisms in
an ecosystem by depicting how
different populations influence the
growth rate of other populations
within the environment.
3. Functional Food Webs

28. Freshwater & Marine Ecosystem
• Its cover more than three-quarters of the
Earth’s Surface.
• Its providing an array of critical
ecosystem services, from participating in
various biogeochemical cycles and
nutrient exchange, to providing natural
protection and habitat, to degrading and
dispersing many environmental
pollutants.

29. The main difference between freshwater and marine
water fish
1.Habitat
2. Species
3. Physiology

30. • Freshwater fish live in
streams, rivers and lakes.
• They can adapt to a change in
habitat, like the rise and fall in
water levels, temperature and
oxygenation levels.
Freshwater Marine water
• Marine life refers to fish
living in oceans and seas.
• These are also known as
saltwater fish because they
can only stay alive in waters
with high salinity levels.
• A marine animal's habitats
include coral reef and
seagrass bed.
1. The habitat

31. • Freshwater fish can be cold
water or tropical.
• Cold water species include
trout and goldfish.
• Tropical freshwater species
are catfish and angelfish.
Freshwater Marine water
• Marine fish are all cold-water
fish.
• These include seahorses,
sharks, common dolphin and
tuna.
2. The Species

32. • Freshwater fish retain more
salt in their bodies than in the
water they live in.
• This is why they can survive in
waters with less than 0.05
percent salinity
Freshwater Marine water
• Saltwater fish lose water to
their surroundings through
the process of osmosis.
• They need to drink lots of
salty water to maintain a
healthy body.
3. The Physiology

33. Promoting Biodiversity
Artificial reefs Coral reefs are home to
invaluable ecological and
economic richness, nurturing
marine species and providing a
natural defense against coastal
erosion.

34. Reefs across the globe have been degraded
by natural and human pressures.
Those in the Arabian Gulf are no exception,
being at risk of disappearance from a
combination of climate change factors and
human activities such as fishing, dredging,
and marine pollution.
Promoting Biodiversity
Artificial reefs
In Saudi Arabia

35. Aramco has actively promoted the growth of
marine life in the Gulf with planned and
unplanned artificial reefs.
In total, 3,247 reef blocks have been
deployed at 25 sites in the Arabian Gulf,
alongside a reef structure in Jizan, Red Sea.
Deployment sites in the Arabian Gulf include
the region of Manifa, Abu Ali, Jubail, Ras
Tanura, Jana Island, Safaniya and Khafji.
Promoting Biodiversity
Artificial reefs
In Saudi Arabia

36. Seasonal monitoring of the artificial reefs
examined productivity, species biodiversity and
fish numbers.
The results indicated that the central part of the
Arabian Gulf, specifically the region of Manifa,
Abu Ali, Jubail and Ras Tanura was the area with
the highest abundance of reef fish, the highest
biodiversity of reef organisms, and the highest
biomass productivity
Promoting Biodiversity
Artificial reefs
In Saudi Arabia

37. THANKS!
Does anyone have any questions?

38. References
https://kids.britannica.com/students/assembly/view/90131
https://www.aramco.com/en/sustainability/minimizing-
environmental-impact/biodiversity-and-land-use/promoting-
biodiversity/artificial-reefs
https://www.nature.com/scitable/knowledge/library/food-web-
concept-and-applications-84077181/
https://www.majordifferences.com/2013/02/difference-between-
grazing-and-detritus.html
https://animals.mom.com/tiger-barb-water-needs-3423.html
https://encounteredu.com/multimedia/images/energy-flow-in-the-
marine-community