『Abstract
Chemical weathering of bedrock is critical to maintaining terrestrial
life, and climate, typically as manifested by precipitation, is
often identified as having a first-order control on rates of chemical
weathering. The ability of precipitation to dissolve rock, however,
is modulated by the properties of the overlying soil that influence
the contact time between water and minerals. Flume experiments
were conducted to investigate the hydrological controls on rates
of chemical weathering. Solute concentrations of runoff flowing
across synthetic bedrock overlain by nonreactive pseudosoils of
differing hydraulic conductivities were measured to examine the
role of seepage velocity in influencing weathering rates on steep
slopes. The results suggest that, where weathering is not limited
by the supply of fresh minerals, weathering rates should increase
with decreasing hydraulic conductivity. In addition, a mathematical
relationship between hydraulic conductivity and chemical weathering
on hillslopes is introduced to explore the hydrological controls
on feldspar and calcite dissolution rates. The mathematical model
supports the results from the experiments.
Keywords: chemical weathering; soil production; dissolution; hydraulic
conductivity; advective-dispersion equation; hillslope hydrology』
Introduction
Materials and methods
Results
Mathematical model
Discussion and conclusion
Acknowledgments
References cited