New research suggests that Earth is
now characterized by a geologically unprecedented pattern of global energy flow
that is pervasively influenced by humans - and which is necessary for
maintaining the complexity of modern human societies.
Credit: © tr3gi / Fotolia
The
impact humans have made on Earth in terms of how we produce and consume
resources has formed a 'striking new pattern' in the planet's global energy
flow, according to researchers from the University of Leicester.
The
research suggests that Earth is now characterized by a geologically
unprecedented pattern of global energy flow that is pervasively influenced by
humans -- and which is necessary for maintaining the complexity of modern human
societies.
The
new study, published in the journal Earth's Future, is led by Professors
Mark Williams and Jan Zalasiewicz of the University of Leicester's Department
of Geology working with an international team of scholars.
While analyzing the Anthropocene phenomenon -- an epoch where humans dominate Earth's
surface geology -- the team identified that human patterns of production and
consumption are a key factor characterizing the epoch, and when measured
against the billion-year old patterns of planet Earth, they form a striking new
pattern.
Professor
Zalasiewicz said: "Very big changes in our planet's pattern of biological
production and consumption do not happen very often. The appearance of
photosynthesis was one, about two and a half billion years ago. Then, a little
over half a billion years ago, animals like trilobites appeared, to add
scavengers and predators into a food web of increasing complexity.
"Other
major events have happened since, such as five major mass extinctions, but even
measured against these events, human-driven changes to production and
consumption are distinctly new."
Dr
Carys Bennett, co-author on the study from the University of Leicester's
Department of Geology, added: "It is without precedent to have a single
species appropriating something like one quarter of the net primary biological
production of the planet and to become effectively the top predator both on
land and at sea."
In
addition, by digging phosphorus out of the ground and by fixing nitrogen out of
the air to make fertilizers; and by exploiting hundreds of millions of
years-worth of stored carbon-based energy in a still-accelerating trend, humans
are increasing productivity well above natural levels -- and directing much of
it towards animals that have been re-engineered to suit our purposes.
Professor
Zalasiewicz added: "This refashioning of the relationship between Earth's
production and consumption is leaving signals in strata now forming, and this
helps characterize the Anthropocene as a geological time unit.
"It
also has wider and more fundamental importance in signaling a new biological
stage in this planet's evolution."
Archaeologist
Dr Matthew Edgeworth, Honorary Visiting Research Fellow at the University of
Leicester's School of Archaeology and Ancient History, added: "Recent
changes in Earth's biosphere, caused in part by human activity, are starting to
become evident in rock and soil strata. Unprecedented strati-graphic signals are
challenging disciplines like geology and archaeology to assess such changes and
put them in temporal context, relative to other major transitions in Earth's
history."
Dr
Colin Waters of the British Geological Survey said: "Modern human society
is structured around economic production and consumption and our recent
perturbation of the balance between the two, notably since the mid-20th
century, will leave a signal that will provide a lasting legacy of our existence
on this planet."
In
2016 the Anthropocene Working Group led by Professor Zalasiewicz will gather
more evidence on the Anthropocene, which will help inform recommendations on
whether this new time unit should be formalized
and, if so, how it might be defined and characterized.
https://www.sciencedaily.com
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