extinction and recovery, interactions among groups, and the effects of
geographic scale. 7
Much can be learned from studies of present-day systems, but access to the
geological record also permits these issues to be explored over longer time scales
and over a wider range of Earth system states. Major scientific breakthroughs are
inevitable because of the enormous growth in the power of new techniques and of
conceptual advances in the contributing biological, geological, and geochemical
disciplines. Geobiological research results bear directly on a wide array of
important scientific and societal issues, including the nature of the Critical Zone,
the stability and resilience of ecosystems under stress, and the origin and
evolution of life itself.
Geobiological processes operate over a wide spectrum of temporal and
spatial scales—from small-scale, rapid exhalation of O 2 by cyanobacteria, to
cycling of carbon through communities of marine phytoplankton and rain forests,
to restructuring of regional and global ecosystems in the wake of major extinction
events, to shifts in reef composition in response to slowly changing rates of
seafloor spreading ( Figure 2.4 ). Understanding the complex interactions that
occur across such a broad space-time spectrum is challenging and requires an
integrated approach that treats ecosystems as components of larger geosystems.
Recent Advances
Over the past decade, Earth scientists have gained much better appreciation
of the impact of living organisms on their surroundings, which is forcing a
critical reexamination of the relative importance of the various factors that
control Earth processes.
Climate Studies
Biominerals provide a sink for atmospheric CO 2 , and their formation is
directly linked to the supply of calcium and magnesium from chemical
weathering of silicate and carbonate minerals. Organic by-products may, in turn,
increase dissolution rates of silicate minerals by factors ranging from 2 to more
than 100. Such biological-climate feedback mechanisms (including
7 See also Dynamic History of the Earth-Life System: A Report to the National Science
Foundation on Research Directions in Paleontology, results of a workshop held in
Washington, D.C., March 6-9, 1999.
SCIENCE OPPORTUNITIES
46
About this PDF file: This new digital representation of the
original work has been recomposed from XML files created
from the original paper book, not from the original
typesetting files. Page breaks are true to the original; line lengths,
word breaks, heading styles, and other typesetting-specific
formatting, however, cannot be retained,
and some typographic errors may have been accidentally inserted.
Please use the print version of this publication as the authoritative
version for attribution.
geographic scale. 7
Much can be learned from studies of present-day systems, but access to the
geological record also permits these issues to be explored over longer time scales
and over a wider range of Earth system states. Major scientific breakthroughs are
inevitable because of the enormous growth in the power of new techniques and of
conceptual advances in the contributing biological, geological, and geochemical
disciplines. Geobiological research results bear directly on a wide array of
important scientific and societal issues, including the nature of the Critical Zone,
the stability and resilience of ecosystems under stress, and the origin and
evolution of life itself.
Geobiological processes operate over a wide spectrum of temporal and
spatial scales—from small-scale, rapid exhalation of O 2 by cyanobacteria, to
cycling of carbon through communities of marine phytoplankton and rain forests,
to restructuring of regional and global ecosystems in the wake of major extinction
events, to shifts in reef composition in response to slowly changing rates of
seafloor spreading ( Figure 2.4 ). Understanding the complex interactions that
occur across such a broad space-time spectrum is challenging and requires an
integrated approach that treats ecosystems as components of larger geosystems.
Recent Advances
Over the past decade, Earth scientists have gained much better appreciation
of the impact of living organisms on their surroundings, which is forcing a
critical reexamination of the relative importance of the various factors that
control Earth processes.
Climate Studies
Biominerals provide a sink for atmospheric CO 2 , and their formation is
directly linked to the supply of calcium and magnesium from chemical
weathering of silicate and carbonate minerals. Organic by-products may, in turn,
increase dissolution rates of silicate minerals by factors ranging from 2 to more
than 100. Such biological-climate feedback mechanisms (including
7 See also Dynamic History of the Earth-Life System: A Report to the National Science
Foundation on Research Directions in Paleontology, results of a workshop held in
Washington, D.C., March 6-9, 1999.
SCIENCE OPPORTUNITIES
46
About this PDF file: This new digital representation of the
original work has been recomposed from XML files created
from the original paper book, not from the original
typesetting files. Page breaks are true to the original; line lengths,
word breaks, heading styles, and other typesetting-specific
formatting, however, cannot be retained,
and some typographic errors may have been accidentally inserted.
Please use the print version of this publication as the authoritative
version for attribution.