Download PPT for Aug 29 HW

Some Terms and Definitions
• Ecosystems: A grouping of plants, animals, and
microbes occupying an explicit unit of space and
interacting with each other and their
environment.
• Ecotone: Transitional region between different
ecosystems.
Ecosystems: A Description
• Biotic communities: grouping or assemblage
of plants, animals, and microbes.
• Species: different kinds of plants, animals, and
microbes in the community.
• Populations: number of individuals that make
up the interbreeding, reproducing group.
• Associations: how a biotic community fits into
the landscape.
Ecotones on Land
• Shares many of the
species and
characteristics of both
ecosystems
• May also include unique
conditions that support
distinctive plant and
animal species
Terrestrial-to-Aquatic-System Ecotone
• Shares many of the
species and
characteristics of both
ecosystems
• May also include unique
conditions that support
distinctive plant and
animal species
Interrelationships Between Ecosystem Components
“Everythingisconnectedtoeverythingelse”
Interrelationships
Example
abiotic x abiotic
temperature and rainfall = climate
abiotic x biotic
water temperature predicts fish species
biotic x abiotic
human pollution of the environment
biotic x biotic
predator/prey relationships, life cycles,
trophic levels
The Structure of Ecosystems
• Trophic categories
• Trophic relationships: food chains, food webs,
trophic levels.
• Nonfeeding relationships: symbiosis
• Abiotic factors
Autotrophs = Producers = Self feeders
Consumers = Heterotrophs
• Primary consumers =
herbivores = rabbit: eat
plant material
• Secondary consumers
= carnivores = predators
= coyotes: prey are
herbivores and other
animals.
Consumers = Heterotrophs
• Parasites = predator = either plant or animal:
prey are plants or animals.
Detritus Food Web
Trophic Categories
Trophic Relationships: Food Chain
Third-order Consumer
Secondary Consumer
Primary Consumer
Producer
Match Organisms with Trophic Level(s)
Trophic Levels
Organisms
Secondary
Consumer
ThirdOrder
Consumer
Snakes
X
X
Owls
X
X
X
X
Plants
Producer
X
Rabbits
Bacteria
Primary
Consumer
X
X
X
Match Trophic Categories with Trophic Level(s)
Trophic Levels
Category
Autotrophs
Producer
Primary
Consumer
Secondary
Consumer
Third-Order
Consumer
X
X
X
X
X
X
X
X
X
Herbivores
X
Carnivores
Omnivores
Parasites
X
Trophic Relationships Among Producers and
Consumers
Food Webs = Food Chain Interrelationships
Trophic Level Energy Flow
Third-order Consumer 1Kcal
- 10x
Secondary Consumer 10 Kcal
- 10x
Primary Consumer 100 Kcal
- 100x
Producer 10,000 Kcal
Biomass Pyramid
Trophic Levels: Pyramid of Biomass
5
4
3
2
1
Which level is occupied by:
producers?
primary consumers?
secondary consumers?
third-order consumers?
Trophic Levels: Pyramid of Energy
5
4
3
2
1
Which level is occupied by:
producers?
primary consumers?
secondary consumers?
third-order consumers?
Nutrient Cycles and Energy Flow
HW Questions
(answer these 5 questions in a Word doc and bring the word doc to next class (do not submit or email it)!
• Q1. How are “ecotone” and “environmental gradient” similar or
different? Explain your answer.
• Q2. Answer the questions presented in Slide 20 and Slide 21 of
this PPT
• Q3. What is the difference between the biotic community and the
abiotic environmental factors of an ecosystem?
» See next slide for more questions
» (always refer to your Pearson IB textbook p.
14-20 while answering)
HW questions (Contd)
• Q4. Define and compare the terms species, population, association, and
ecosystem.
• Q6. Compared with an ecosystem, what are an ecotone, landscape, biome,
and biosphere?
• Q7. Identify and describe the biotic and the abiotic components of the
ecosystem such as the Gulshan Lake that is a part of your community.
• Q8. Name and describe the roles of the three main trophic categories that
make up the biotic structure of every ecosystem. Give examples of
organisms from each category.