- Material flow accounting
Material flow accounting (MFA) is the study of material flows on a national or regional scale. It is therefore sometimes also referred to as regional, national or economy-wide material flow analysis.
The goal of material flow accounting is to ensure national planning, especially for scarce resources, and to allow forecasting. It also allows to assess environmental burdens through economic activities of a nation or to determine how material intensive an economy is.
The principle concept underlying MFA is a simple model of this interrelation between the economy and the environment, in which the economy is an embedded subsystem of the environment. Similar to living beings, this subsystem is dependent on a constant throughput of materials and energy. Raw materials, water and air are extracted from the natural system as inputs, transformed into products and finally re-transferred to the natural system as outputs (waste and emissions). In order to highlight the similarity to natural metabolic processes, the terms “industrial” or “societal” metabolism have been introduced.
In MFA studies for a region or on a national level the flows of materials between the natural environment and the economy are analyzed and quantified on a physical level. The focus may be on individual substances (e.g. Cadmium flows), specific materials, or bulk material flows (e.g. steel and steel scrap flows within an economy). Research on MFA is strong in Germany, Austria and the United States. Researchers in this field are organized in the ConAccount network.
Statistics related to material flow accounting are usually compiled by national statistical offices, using economic, agricultural and trade statistics measuring the exchange of material between different products available in an economy.
Terms and Indicators
Statistics related to material flows are usually combined in different indicators. Some of these indicators are listed below. More information on how the statistics are collected, under what legal framework and how they are defined is available on Economy-wide material flow accounts
The following indicators are commonly used in material flow accounting to measure the resource efficiency of a country or region:
Total Material Requirement (TMR) includes the domestic extraction of reources (minerals, fossil fuels, biomass), the indirect flows caused by and associated with the domestic extraction (called "Hidden Flows") and the imports.
Domestic Material Input (DMI) summarizes the domestic extraction of reources and the imports, but excludes the indirect flows associated with the domestic extraction, since they are sometimes difficult to quantify.
Direct Material Consumption (DMC): this indicator accounts all materials that are consumed within or remain in the domestic environment. The quantity is the domestic material input minus the exports out of the economy.
Domestic Processed Output (DPO) is defined by the OECD as "the total mass of materials which have been used in the national economy, before flowing into the environment. These flows occur at the processing, manufacturing, use, and final disposal stages of the economic production-consumption chain."
Total Domestic Output (TDO) includes the domestic processed output (DPO) plus the hidden flows associated with the domestic production.
Net Addition to Stocks (NAS), the materials that are neither released to the domestic environment nor exported, but contribute to a physical increase of the economic processing system itself, e.g. infrastructure, buildings, machinery or other durable goods.
Hidden Flows are materials that are extracted or moved, but do not enter the economy. According to OECD, the "displacement of environmental assets without absorption into the economic sphere", such as overburden from mining operations.
- ^ Definition taken from http://www.materialflows.net
- ^ ConAccount
- ^ OECD Glossary http://stats.oecd.org/glossary/detail.asp?ID=6403
- ^ OECD Glossary http://stats.oecd.org/glossary/detail.asp?ID=6472
- Industrial ecology
- Industrial metabolism
- Economy-Wide Material Flow Accounts
- Material flow analysis
- Input Output Analysis
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