Other
Scientific paper
May 1995
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1995gecoa..59.1729w&link_type=abstract
Geochimica et Cosmochimica Acta, vol. 59, Issue 9, pp.1729-1747
Other
90
Scientific paper
Climatic effects on chemical weathering are evaluated by correlating variations in solute concentrations and fluxes with temperature, precipitation, runoff, and evapotranspiration ( ET ) for a worldwide distribution of sixty-eight watersheds underlain by granitoid rock types. Stream solute concentrations are strongly correlated with proportional ET loss, and evaporative concentration makes stream solute concentrations an inappropriate surrogate for chemical weathering. Chemical fluxes are unaffected by ET , and SiO 2 and Na weathering fluxes exhibit systematic increases with precipitation, runoff, and temperature. However, warm and wet watersheds produce anomalously rapid weathering rates. A proposed model that provides an improved prediction of weathering rates over climatic extremes is the product of linear precipitation and Arrhenius temperature functions. The resulting apparent activation energies based on SiO 2 and Na fluxes are 59.4 and 62.5 kJ·mol -1 , respectively. The coupling between temperature and precipitation emphasizes the importance of tropical regions in global silicate weathering fluxes, and suggests it is not representative to use continental averages for temperature and precipitation in the weathering rate functions of global carbon cycling and climatic change models. Fluxes of K, Ca, and Mg exhibit no climatic correlation, implying that other processes, such as ion exchange, nutrient cycling, and variations in lithology, obscure any climatic signal. The correlation between yearly variations in precipitation and solute fluxes within individual watersheds is stronger than the correlation between precipitation and solute fluxes of watersheds with different climatic regimes. This underscores the significance of transport-induced variability in controlling stream chemistry, and the importance of distinguishing between short-term and long-term climatic trends. No correlation exists between chemical fluxes and topographic relief or the extent of recent glaciation, implying that physical erosion rates do not have a critical influence on chemical weathering rates.
Blum Alex E.
White Art F.
No associations
LandOfFree
Effects of climate on chemical weathering in watersheds does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Effects of climate on chemical weathering in watersheds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Effects of climate on chemical weathering in watersheds will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1060337