Environmental Significance

Metals recycling rate


Quantity of recycled and secondary metals consumption/Total metals consumption

Materials efficiency and cyclicity

Renewable net carbon balance


Forest growth/Forest products harvested

Global carbon balance of sources and sinks, land use, ecosystem disruption

Output intensities

Green productivity


Quantity of solid wastes/Quantity of total solid physical outputs

Materials efficiency and cyclicity

Intensity of use for residues

MMT/$106 GDP

Generation quantity for selected materials waste streams/GDP in constant dollars

Relationship of waste generation to economic activity

Leak indices

Dissipation index


Quantity of materials dissipated into the environment/Total material outputs

Materials efficiency and cyclicity, media contamination

Nutrient and metals loadings

mg/liter and kg/km2

Concentrations of pollutants in water bodies, and land deposition of nutrients and heavy metals/Defined area

Materials monitoring and accounting, media contamination

Environmental trade index


Net mass value of waste and emissions generated from foreign trade in manufactured products and raw resources

Domestic resource consumption, domestic environmental burden caused by exported goods

Mining efficiency

Mining wastes


Quantity of wastes generated/ Ton of finished product

Solid wastes, acid mine drainage

By-product recovery


Total by-product recovery/Total output

Materials efficiency, solid wastes

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