Trials are made with laying hens divided into 4 groups, which are being given rations containing lead and cadmium corresponding to those existing in regions with high technogenic Clark. Two new criteria are proposed for improvement of the efficiency of anthrozoocenosis management, which define the chemical heterogeneity of the biosphere at organism and sub-organism level: distribution Clark and safety Clark. | New criteria for chemical heterogeneity of the biosphere Distribution of cadmium and lead in laying hens
