Vegetation activity

The influence that variations of temperature and levels of atmospheric CO2 and O2 have on chemical weathering are more subtle. Temperature appears to have a direct effect on weathering rate (White and Blum, 1995). The silica concentration of rivers (Meybeck, 1979, 1987) and the alkalinity of ground waters in carbonate terrains (Harmon et al., 1975) are both positively correlated with temperature variations. It is not clear, however, whether temperature-related variations in weathering rates are largely due to variations in vegetational activity that parallel temperature variations. 

BeerUng D. J. (1999) The influence of vegetation activity on the dole effect and its implications for changes in biospheric productivity in the mid-holocene. Proc. Roy. Soc. of London Ser. B-biol. Set 266(1419), 627-632. 

Recent Slow Rate of COj Increase and Vegetation Activity... 

The vegetation activity has grown in the Northern Hemisphere in accord with the surface warming in the 1986-91. 

Of the 373 (cereal) or 399 (fmit and vegetables) active agents analyzed, those with N2 > 3% are listed. 

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