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BIOGEOGRAPHY
Theme 1:
THE RELATIONSHIP BETWEEN GEOGRAPHY,
BIOGEOGRAPHY AND ENVIRONMENTAL
MANAGEMENT
Lecture 1
What is Biogeography?
Biogeography: the large-scale geographic
pattern in the distribution of species, and the
causes and history of this distribution. Zoogeography
Phytogeography
Lecture 2
Environmental Science: the study of the complex
interactions of human populations with matter and
energy resources; it incorporates aspects of the
natural and social sciences, business, law,
technology, and other fields.
Lecture 3
Vicariance biogeography:
The distribution of organisms depends on their
normal means of dispersal; e.g., disjunctions are
explicable in terms of new barriers (rivers, rises in
sea-level, etc.) having split formerly continuous
ranges, rather than in terms of the organisms hopping
over already existing barriers.
The Gaia Principle
First described by James Lovelock in 1979, the Gaia Principle describes the
Earth as a single, living organism, with all its biological, geological,
chemical and hydrological processes acting in concert, to regulate the planet
and ensure its survival through an exquisite array of feedback loops.
An example of a Gaia feedback loop is the relationship between plants and
carbon dioxide. When carbon dioxide levels rise in the atmosphere, plants
are able to grow better and extract more carbon dioxide – thereby
“balancing” the Earth as a complex system.
But some scientists criticise the Gaia Principle because it can’t be tested.
They say it is impossible for “stabilising” feedback loops to evolve as
described by Lovelock, and argue that the Earth is ever-changing