The Science of Geography
The
term “Geography” is composed of two Greek words ‘Geo’ meaning Earth and "Graphien" means to write.
To
the ancient Greeks Geography was “a Description of the earth”
Geography is the science that studies
the relationships among areas, natural systems, cultural activities and the
interdependence of all these over space.
Why is Geography unique
among all disciplines?
·
Its
primary concern with how things are distributed on the earth’s surface.
·
Its
use of graphics (maps, pictures, photography) in its methods of study.
·
Its
adoption of an interdisciplinary
approach to study problems of the earth.
·
Geography
is not defined by its subject matter (the things it studies) but rather the
approaches it takes to study those materials.
Geography is defined by 5
key themes:
1) Place 2)
Location 3)
Movement
4) Region 5) Human-earth relationships
A bridge between Natural
& Social Sciences
The
human habitat is made up of:
a)
A natural environment comprising
natural features: eg. rivers, weather, soils & vegetation and,
b)
A cultural environment, consisting
of products of human civilization e.g. schools, cities, computers.
(1)
Physical Geography: spatial analysis of
physical elements and processes that make up the environment. The study focuses
on the natural environment (weather, mountains, soil, etc.).
(2)
Human Geography studies products of human
civilization embodied in our cultural environment.
Earth System Concepts
A system refers to “an organized and interrelated set of
things, and their attributes that work together as a unit. The parts are linked
by flows of energy and matter.
A
system that receives inputs of energy and matter and then outputs materials
into surrounding environments is termed: Open System
(e.g. systems in human body)
A
system that is shut off from the surrounding environment and is self-contained
is termed: Closed System (e.g.
the earth system).
Feedback: information and other materials that are returned
to parts of a system to influence its continuous operation.
Negative feedback: Information that tends to stabilize a system
by slowing its rate, or reducing output when its effects are too great
(daylight and photosynthesis).
Positive feedback: Information that encourages response and
hence stimulates growth in the system (dried shrubs & oxygen and
wildfires).
Steady-state equilibrium occurs when rates of
inputs and outputs of energy and matter within the system are constant or fluctuate around a stable average.
Earth’s Spheres
Elements
on the earth can be grouped into two classes:
a)
Biotic elements –
the living system including all plants, animals, and micro-organisms.
b)
Abiotic elements –
the non-living elements of the earth on which living things depend. The are:
1)
Atmosphere – the
mass of air (gases)
2)
Hydrosphere –
all forms of water
3)
Lithosphere - outer part of the solid
earth
4)
Biosphere: Interconnected web that
links all organisms with the physical environment. The worldwide system within
which all life functions.