Forest soil, metal flux

The values of output metal fluxes mentioned above vary as a function of spatial distributed parameters including climate, soil and forest-type data. As a basis for computing critical loads, an overlay of three maps was made ... 

We have considered only two biogeochemical metal fluxes (accumulation in wood biomass and leaching) that exist in the forest ecosystems. Both of these fluxes contribute to the removal of heavy metals from soil solution and, consequently, to the ecosystem depletion in HM. The calculated values of critical loads of lead ranged from < 50g/ha/yr. to > 250g/ha/yr. Cadmium critical loads are within the limits < 5 and > 25 g/ha/yr. 

Atmospheric dry and wet deposition contribute significantly to the metal fluxes in forest soils (Lindberg et al. 1982). An assessment of dry deposition and foliar leaching of mercury and selected trace metals based on washed foliar and surrogate surfaces has been recently presented by Rea et al. (2000). In another set of investigations. 

In forest ecosystems these symbols stand for CL(M) is critical load of a heavy metal (g ha-1 a-1) Mu is metal net uptake in wood biomass under critical loads conditions (g ha-1 a 1) Mle(crit) is critical leaching flux of metal with drainage water (from the uppermost 10 cm soil layer) (g ha-1 a-1). 

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