This is a basic presentation of ecology.

1. -----------------------------------Education--------------------
University of Chittagong ,Bangladesh and
Florida Gulf Coast University, Florida, USA
Name: - Hafez Ahmad
I am passionate about Hydrology, GIS, remote sensing ,
Ecology and Wildlife research .
----------------------------------- Research-----------------------
----------------------------------- Experiences/ previous jobs-
I worked (Oct 2020- NOV 2021) for Wildlife Conservation
Society(WCS) Bangladesh Program as A Marine Data
Management officer, WCS Bangladesh
Mississippi State University
Department of Wildlife, Fisheries and Aquaculture
Mobile: +8801785601208
Email: ha626@msstate.edu
Thompson Hall ,220 (18) , 9AM to 2 PM
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2. Introduction to Ecology
The word ecology was given by Biologist Hackle in 1869. it derived from Greek words “oikos”,
meaning habitat or place of living and “logos” meaning to study.
Ecology- The scientific study of interactions
between organisms and their environments,
focusing on energy Transfer.
The fundamental idea behind the study of
ecology is that all organisms are
interdependent.
What do organisms need to survive?
1. Food
2. Water
3. shelter
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3. Environmental Factors
The environment is made up of two factors
a. Biotic factors- All living organism inhabiting the earth
(i.e. plants, animals, and bacteria)
a. Abiotic factors- nonliving parts of the environment
(i.e. temperature, soil, light , rainfall)
3 https://www.homeworklib.com/qaa/894110/what-are-biotic
and-abiotic-factors-in-an

4. Biosphere
Ecosystem
Community
Population
Organism
Unicellular or multicellular form
exhibiting characteristics of life: Fish, human
A group of organisms of one species living in the
same place at the same time
Several interacting populations that inhabits
a common environment and are interdependent
Population in community and the abiotic
factors with which they interact (ex. Marine)
Life supporting portions of earth composed of
air, land freshwater and salt water
Levels of Ecological Organization
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5. Ecosystem
Ecosystem is a physical place where plants, animals,
As well as weather and landscape work together to form
A bubble of life. It contains abiotic and biotic components.
It can be very large (tropical rainforest )or very small(pond).
Typical lake Ecosystem
Every factor in an ecosystem depends on every other factor, either
directly or indirectly. A change in the temperature of an ecosystem will
often affect what plants will grow there, for instance. Animals that
depend on plants for food and shelter will have to adapt to the
changes, move to another ecosystem. But Climate change and global
warming are leading threats to the ecosystems.
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https://www.biologyonline.com/tutorial
s/freshwater-producers-and-consumers

6. Classification of Ecology
Based on Environment or habitat
1. Aquatic ecology- study of the plants and animals
that live in our rivers , streams, ocean, lake and their
interactions
a. Marine ecology : Ocean , deep sea and estuary.
b. Freshwater ecology
I. Lotic (running water) : river, stream
II. Lentic (standing water): pond , lake
2. Terrestrial ecology : study of interaction of organism
on land.
a. Grassland ecology: ecology of grasslands, which are
regions dominated by grass species but containing other
non-woody plants
b. Forest ecology: ecology of wooded areas, including
rainforest, deciduous and evergreen, temperate and
boreal forest.
c. Desert ecology : study of interactions between both
biotic and abiotic components of desert environments
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https://www.behance.net/gallery/12437951/Natu
re-Forest-Ecology-Art
https://www.dvarminz.
com/index.php?main_
page=product_info&pr

7. Types of species interactions
Parasitism Commensalism Mutualism
Neutralism Commensalism
Competition Parasitism
Species B
Species
A
+
0
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- 0 +
Symbiosis is a close ecological relationship between the individuals of two (or more) different species.
Sometimes a symbiotic relationship benefits both species, sometimes one species benefits at the other's expense,
and in other cases neither species benefits.
Ecologists use a different term for each type of symbiotic relationship:
Commensalism -- one species benefits, the other is unaffected
Parasitism -- one species benefits, the other is harmed
Competition -- neither species benefits
Neutralism
Mutualism
-- both species are unaffected
-- both species benefit
Mutualism Commensalism
Parasitism 7

8. Habitat and Niche
Habitat – the place in which an organism lives out its life .i.e. address. And Niche- The role of a
species play in a community. . i.e. Job
Ex. Honey bees lives in the bee hive , forest (Habitat)
Honey bees job is to pollinate flowers to make honey (Niche)
Habitat focuses on how the environment impacts the organism while Niche focuses on how the
organism impacts the environment.
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Niche
Habitat
Niche

9. There are 3 main types of feeding relationships
1. Producer-consumer: Producer: all autotrophs (plants) trap energy
from the sun. Consumer (heterotrophs) they ingest food containing
the sun’s energy. Consumers are divided into
a. Primary consumers (plant eaters). They directly depend on the plants
for their food. Insects, deer, cow
b. Secondary consumers (meat eater). They feed on primary
consumers. Frog, cat, snake , foxes
c. Tertiary consumers (meat eaters). They feed on secondary consumers.
tigers, lions
2. Predator-prey: predators are biotic limiting factors . They control
population
Size by feeding on prey. This needs balanced.
3. Parasite-host: The parasite lives on or in the body of the host. A few
examples of parasites are tapeworms, fleas.
Feeding relationships
Trophic levels
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https://onlinesciencenotes.com/trophic-
levels-and-ecological-pyramids/

10. Food Chain Food Web
The arrow points to the eater and shows the transfer of trapped energy
Food webs show all of the possible paths
That energy can take in the ecosystem.
It also shows how organism are dependent on
each other in the ecosystem
A food chain shows a one way flow of energy
in an ecosystem. A food chain is a linear
network of links in a food web starting from
producer organisms and ending at an apex
predator species, detritivores, or decomposer
species.
Each level of a food chain represents a
different trophic level.
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https://www.thinglink.com/scene/786024112798564354

11. Assignment and quiz
1. What is the role of organisms in the ecosystems? 1 points
2. Explain different between habitat and niche 2 points
3. Why are you interested in studying aquatic ecology? 5 points
1. Abiotic component of the Lake ecosystem
a. Plants
b. Fish
c. Temperature
d. Birds
2. The natural place of an organism or community is known as
a. Niche
b. Biome
c. Habitat
d. Habit
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Ans. 2-3 page,11 font single spaced , Due Jan 13 at 11:59pm

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