『Abstract
Quantitative understanding of variability in weathering fluxes
on the modern Earth is limited because little is known about where
the most important weathering reactions take place. This is partly
because the locus of weathering is difficult to measure empirically.
Inverse analysis of a parametric model presented here provides
first-order constraints on variability in the thickness of the
zone of active weathering. Results suggest that the effective
thickness of the weathering zone varies relatively little across
several orders of magnitude of denudation rate. At low to moderate
denudation rates, reactions in soils may dominate weathering fluxes
at the catchment scale, but the contribution from soil weathering
decreases at higher denudation rates. Consequently, increased
erosion leads to higher weathering fluxes, sustained by progressively
greater contributions from weathering in bedrock. The effect of
climate (temperature and runoff) on weathering fluxes is apparently
weaker at low denudation rates than at high denudation rates,
such that erosion, and potentially associated bedrock weathering,
may be important for maintaining climate-stabilizing feedbacks
in Earth's carbon cycle. 』
Introduction
Reaction rates
Parameterizing weathering zone thickness
Inverse analysis of weathering thickness
Variation in weathering flux
Role of climate and implications for carbon-cycle feedbacks
Acknowledgments
References cited