Download Lesson Overview

Lesson Overview
What is Ecology?
Lesson Overview
3.1 What Is Ecology?
Lesson Overview
What is Ecology?
THINK ABOUT IT
How is Earth, in a scientific sense, a
“living planet”?
Lesson Overview
What is Ecology?
Studying Our Living Planet
Ecology is the scientific study of interactions
among organisms and between organisms and their
physical environment.
Lesson Overview
What is Ecology?
Studying Our Living Planet
The biosphere consists of
all life on Earth and all
parts of the Earth in which
life exists, including land,
water, and the atmosphere.
The biosphere extends
from about 8 km above
Earth’s surface to as far as
11 km below the surface of
the ocean.
Lesson Overview
What is Ecology?
The Science of Ecology
Ecology is the scientific study of interactions among and
between organisms and their physical environment.
Interactions within the biosphere produce a web of
interdependence between organisms and the environments
in which they live.
Organisms respond to their environments and can change
their environments, producing an ever-changing biosphere.
Lesson Overview
What is Ecology?
Ecology and Economics
Economics is concerned with interactions based on money.
Economics and ecology share the same word root oikos
(economics). Indeed, human economics and ecology are linked.
Humans live within the biosphere and depend on ecological
processes to provide such essentials as food and drinkable
water that can be bought and sold for money.
Lesson Overview
What is Ecology?
Levels of Organization
Ecological studies may focus on levels of
organization that include the following:
Individual organism
Lesson Overview
What is Ecology?
Levels of Organization
Population—a group of individuals that belong to
the same species and live in the same area
Lesson Overview
What is Ecology?
Levels of Organization
Community—an assemblage of different
populations that live together in a defined
area
Lesson Overview
What is Ecology?
Levels of Organization
Ecosystem—all the organisms that live
in a place, together with their physical
environment
Lesson Overview
What is Ecology?
Levels of Organization
Biome—a group of ecosystems that
share similar climates and typical
organisms
Lesson Overview
What is Ecology?
Levels of Organization
Biosphere—our entire planet, with
all its organisms and physical
environments
Lesson Overview
What is Ecology?
Lesson Overview
What is Ecology?
Organismal Ecology: how organism's structure, physiology &
behavior meet the challenges of its environment.
Population Ecology: factors that affect population size & changes
through time.
Community Ecology: interactions between species such as
predation & competition affect community structure.
Ecosystem Ecology: energy flow & chemical cycling between
organisms & the environment.
Landscape Ecology: factors controlling exchange of energy,
materials & organisms across ecosystems.
Global Ecology: regional exchange of energy & materials
influences functioning & distribution of organisms across the
biosphere.
Lesson Overview
What is Ecology?
Biotic and Abiotic Factors
Biotic factors: biological (living) factors of an
ecosystem
Abiotic factors: Physical components (nonliving)of
an ecosystem
Lesson Overview
What is Ecology?
Biotic Factors
Biotic factors relating to a bullfrog might include algae
it eats as a tadpole, the herons that eat bullfrogs, and
other species competing for food or space.
Abiotic factors: a bullfrog could be affected by water
availability, temperature, and humidity.
Lesson Overview
What is Ecology?
Biotic and Abiotic Factors Together
The difference between abiotic and biotic factors is
not always clear. Abiotic factors can be influenced by
the activities of organisms and vice versa.
For example, pond muck contains nonliving particles,
and also contains mold and decomposing plant
material that serve as food for bacteria and fungi.
Lesson Overview
What is Ecology?
Biotic and Abiotic Factors Together
Trees and shrubs affect:
amount of sunlight the area receives
range of temperatures
humidity of the air
chemical conditions of the soil.
A dynamic mix of biotic and abiotic factors
shapes every environment.
Lesson Overview
What is Ecology?
Ecological Methods
Regardless of their tools, modern ecologists use three
methods in their work: Each approaches relies on
scientific methodology!
observation
experimentation
modeling
Lesson Overview
What is Ecology?
Observation
Observation is often the first step in asking
ecological questions.
Questions may form the first step in designing
experiments and models.
Lesson Overview
What is Ecology?
Experimentation
Experiments can be used to test hypotheses.
An ecologist may set up an artificial environment in
a laboratory or greenhouse, or carefully alter
conditions in selected parts of natural ecosystems.
Lesson Overview
What is Ecology?
Modeling
Many ecological events occur over such long periods
of time or over such large distances that they are
difficult to study directly.
Ecologists make models to help them understand
these phenomena.
Lesson Overview
What is Ecology?
Sampling Techniques
Random sampling is usually carried out when the area under study is fairly uniform,
very large, and or there is limited time available. When using random sampling
techniques, large numbers of samples/records are taken from different positions
within the habitat.
Systematic sampling is when samples are taken at fixed intervals, usually along a
line. For example you might use a transect to show the changes of plant species
as you moved from grassland into woodland.
Lesson Overview
What is Ecology?
Stratified sampling
Stratified sampling is simply the process of identifying areas within an overall
habitat, which may be very different from each other and which need to be
sampled separately. Each individual area separately sampled within the overall
habitat is then called a stratum.