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or harmony between elements that can easily be broken by external interference.
Any anthropomorphic projection of harmony or stability to ecosystems is naïve
however. The history of evolution is the history of change: species, their diversity,
morphology and physical distribution, the chemical composition of the biosphere,
the geography of the earth—all have changed significantly over evolutionary time.
The ecosystem's stability is seemingly transitory then, tied to the shifts in species
distribution and environment.
2.3.1 Biological Ecosystems
Of course, ecosystems and Ecology are the domain of Biology, where we find a
formal understanding, along with many inspirational ideas on the functional re-
lationships found in real biological ecosystems. Modern Ecology is the study of
species and their relations to each other and their environment. The term “Ecology”
originated with the German Biologist and Naturalist, Ernst Haeckel,
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who, in 1866,
defined it as the “science of the relationship of the organism to the environment”,
signifying the importance of different species embedded in specific environments.
The term “Ecosystem”, from the Greek (o
ικ
o
ς
, household;
λ
o
γ
o
ς
, knowledge) is
attributed to the British Ecologist, Sir Arthur Tansley, who coined it from fellow
Botanist Arthur Clapham. It grew out of debates at the time about the similarity of
interdependent communities of species to “complex organisms”. Importantly, Tans-
ley's use of the term ecosystem encompassed “the inorganic as well as the living
components” (Tansley
1939
), recognising that the organism cannot be separated
from the environment of the biome, and that ecosystems form “basic units of na-
ture” (Willis
1997
).
Contemporary definitions of ecosystems begin with the work of American Ecolo-
gists Eugene and Howard Odum. Eugene wrote the first detailed Ecology text,
Fun-
damentals of Ecology
, published in 1953. Odum recognised energy flows, trophic
levels,
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functional, and causal relationships that comprised the ecosystem. Willis
defines the modern concept of an ecosystem as “a unit comprising a community
(or communities) of organisms and their physical and chemical environment, at any
scale, desirably specified, in which there are continuous fluxes of matter and energy
in an interactive open system” (Willis
1997
).
In more modern terms, Scheiner and Willig (
2008
) nominate seven fundamental
principles of ecosystems:
1. Organisms are distributed in space and time in a heterogeneous manner (inclu-
sionary rule).
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Danish biologist Eugen Warming is also attributed as the founder of the science of Ecology.
8
Autotrophs
, such as plants, produce organic substances from simpler inorganic substances, such
as carbon dioxide;
heterotrophs
unable to perform such conversions, require organic substances as
a source of energy.
