Download Ecosystems - MrsMorritt

Ecosystems: biodiversity and sustainability
Introduction
The word “ecology” comes from the Greek “oikos”, meaning ________________ and “logos”,
meaning ___________________.
In ecology we study “communities at home”, or ecosystems.
Ecosystems 1
Explain the concept of an ecosystem and how ecosystems are interlinked to form
one biosphere.
The Concept of ECOSYSTEM
The ecosystem includes a ________________ and an ________________ part. It also includes the
_____________________ or relationships between these parts. The functioning of this system
depends on the functioning of each of these components;
1. The _______________________, including _______________________
______________________________________________________________
2. The _______________________, including _______________________
______________________________________________________________
3. The __________________________ between these.
4. Ecosystems require an input of ____________________ to “drive “them.
Ecosystems vary in size but must be big enough to allow all of the interactions that are necessary to
maintain it.
Interactions between
organisms and the abiotic
environment
Interactions between
members of the same species
Morritt:C:\My Documents\12 BIOLOGY\Ecosystem Balance\Class notes
Interactions between members of
different species.
-1-
When the presence of a particular species in an ecosystem is of major importance in maintaining an
ecosystem, it is said to be a keystone species.
Examples: In Antarctica the keystone species would be ________________________________.
In a Eucalyptus woodland supporting koalas the keystone species would be __________________
REVIEW OF TERMINOLOGY
ORGANISM
SPECIES
POPULATION
COMMUNITY
HABITAT
NICHE
AUTOTROPH
HETEROTROPH
DECOMPOSER
Morritt:C:\My Documents\12 BIOLOGY\Ecosystem Balance\Class notes
-2-
THE CONCEPT OF THE ECOSYSTEM
In a stable ecosystem ________________________________________________________________
__________________________________________________________________________________
__________________________________________________________________________________
THE BIOSPHERE
Morritt:C:\My Documents\12 BIOLOGY\Ecosystem Balance\Class notes
-3-
The original source of energy for the ecosystem is the _____________________ which radiates
__________________________ energy.
AUTOTROPHS or _____________________ are usually ______________ plants which convert
radiant (light) energy into _____________________ energy in the form of carbohydrates. The
simplest of these are the _________________________ and ________________ is an example of
this.
A word equation for this process of __________________________________;
HETEROTROPHS or __________________________ are organisms that need to eat the simple
carbohydrates, like ______________________ in order to make their own larger molecules such as
________________________, __________________________, or _________________________ .
DECOMPOSERS or “THE LITTLE ROTTERS” are usually ___________________ and
_________________ which digest complex organic molecules and convert them to simple
__________________________ . These may then be cycled through the ecosystem by
_______________________ which absorb them through their ________________.
DETRITIVORES are organisms which feed on dead material. They are usually invertebrates
such as ________________, __________________, and ________________.
MATTER is ___________________________ through an ecosystem.
Eg.
ENERGY _____________________________ through an ecosystem.
Energy enters as ______________ and is converted to ________________ energy. This is then lost
to the ecosystem as ____________________ energy.
BIOMASS and PRODUCTIVITY
Biomass of an ecosystem is the total dry weight of matter in the system. It is measured in dry weight
per unit area (eg. grams per square metre).
Productivity refers to the rate at which this biomass accumulates ie how fast matter is added
(grows). Productivity is measured in dry weight (or energy) per unit are per unit time (eg. grams or
kilojoules per square metre per year).
Morritt:C:\My Documents\12 BIOLOGY\Ecosystem Balance\Class notes
-4-
ENERGY FLOWS THROUGH AN ECOSYSTEM
PRODUCER
Chemical
energy
CONSUMER
DECOMPOSER
Cellular
respiration
New tissue
Chemical
energy
Cellular
respiration
New tissue
Cellular
respiration
New tissue
Chemical
energy
MATTER IS RECYCLED- A GENERAL MODEL
(You have studied the carbon, and nitrogen cycles in detail)
BIOTIC
COMMUNITY
ABIOTIC
COMMUNITY
Morritt:C:\My Documents\12 BIOLOGY\Ecosystem Balance\Class notes
-5-