General approaches for calculating critical loads of heavy metals

General Approaches for Calculating Critical Loads of Heavy Metals Discussing the problems related to the critical load calculation, an attention should be paid to (i) selection of a receptor of concern, (ii) critical limits, (iii) possible calculation methods, (iv) the necessary input data and (v) the various sources of error and uncertainty (de Vries andBakker, 1998a, 1998b). 

Deriving Biogeochemical Parameters for Critical Loads of Heavy Metals Selection of a Receptor of Concern 

In general terms, a receptor is defined as an ecosystem of interest that is potentially polluted by a certain load of heavy metal. 

Soil microbes. Effects include reduced microbial biomass and/or species diversity, thus affecting microbial processes such as enzyme synthesis and activity, litter decomposition, associated with carbon and nitrogen mineralization, and soil respiration  

Soil fauna, including invertebrates, like nematodes and earthworms. Effects are connected with biodiversity, productivity and biomass changes  

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