An ecosystem is a complete community of living organisms and the
nonliving materials of their surroundings. Thus, its components include
plants, animals, and microorganisms; soil, rocks, and minerals; as well as
surrounding water sources and the local atmosphere. The size of ecosystems
varies tremendously. An ecosystem could be an entire rain forest, covering a
geographical area larger than many nations, or it could be a puddle or a
backyard garden. Even the body of an animal could be considered an
ecosystem, since it is home to numerous microorganisms.
Ecology continued
 Ecology is the study of how organisms interact with
one another and with their environment.
 Ecology helps us to understand how all insects,
animals, plants, humans every organism affects one
another.
Ecology
 We often think of pests as annoying little bugs like
mosquitoes. The real definition of a pest is organisms
that cause problems to humans. Indeed pests are
annoying but they are essential in our environment
and the food chain. Although they are pests to humans
they are food for other organisms. So as you can see
there are many factors that affect the food chain, from
the tiniest insect to the largest animal.
Ecology
Ecology
 The biotic factors are the living components of an
ecosystem ---- the plants, animals, and other living
things. In a lake ecosystem you could find the
following biotic factors such as fish, snails, frogs, water
lilies and plankton. The abiotic factors include the
physical components such as air, soil, water, heat, and
light. In a lake ecosystem you could find the following
abiotic factors such as water, rocks, sand and minerals.
 The two factors that determine climate are latitude
(distance from the equator) and altitude (elevation
above sea level). Different ecosystems prosper in
different climate and places.