Ecosystems, Components, Energy flow and Matter cycling

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Ecosystems, Components, Energy flow and Matter
cycling
All living organisms are composed of cells,
either unicellular i.e. microorganisms, like
bacteria, algae, yeast or multicellular i.e.
fungus, plants, animals Organized in cells,
tissue, organs,
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Some properties of life
-reproduction either a-sexual and or
sexual -growth and development -energy
utilization -response to the environment -evolutio
nary adaptation
What about a virus?
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What is a species?
Historically and still today many different
definitions. Many arguments about what is a
species for example, morphological versus genetic
studies
The Biological Species Definition Defines a
species as a population or group of populations
whose members ( conspecifics) have the potential
to interbreed with one another in nature to
produce viable, fertile offspring.
Problems fossils, asexual reproducing
individuals etc.
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Population
A group of individuals of one species that live
in a particular geographic area. The area is
called a habitat.
Habitat specialist, versus generalists. Which one
is more vulnerable to sudden changes in the
environment (i.e. natural or anthropogenic
changes) ??
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Characteristics of population parameters (i.e.
Population Ecology, or genetics) are driven by
environmental Changes (i.e. daily rhythms,
seasons, climate, weather cycle).

• population size
• -distribution
• -age classes (juveniles, sub adults adults)
• -reproduction (seasonal/a-seasonal)
• -individual genetic variation within a population
• (sexual reproduction, randomness)
• Crucial parameter for ecology and conservation
  biology

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Communities
All organisms that inhabit a particular area
(habitat). An assemblages of populations of
different (plant animal) species living close
enough together for potential interactions. (Commu
nity Ecology) i.e. Bird or plant community, or
coral reef community
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Ecosystems
All organisms in a given area as well as the
abiotic factors with which they interact. It is
a community (assemblages of species) and its
physical environment. For example, rainforest,
coral reef, pineland forest, the
Everglades, Artificial (human-created)
ecosystems include agriculture areas, fish
ponds, lakes, coral reefs etc.
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The One and Only Biosphere
The entire portion of the Earth that is inhabited
by life, the sum of all the planets communities
and ecosystems.
The Biosphere includes the lower atmosphere,
lithosphere (earths crust), and the hydrosphere
(water bodies).
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Fig. 4.6, p. 74
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What sustains Life on Earth

• Sun as an energy resource
• 2. Organic and inorganic material flow through
  the food web

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The Source of Energy
64 of solar energy is reflected or absorbed
Remaining energy 1. Warms the troposphere, and
Lithosphere. 2. Effects on Climate (water
evaporation) 3. Photosynthesis
Fig. 4.8, p. 75