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Global patterns in human consumption of net primary production
Marc L Imhoff1, Lahouari Bounoua, Taylor Ricketts
1Biospheric Sciences Branch, NASA Goddard Space Flight Center, Greenbelt, Maryland 20771, USA. Marc.L.Imhoff@nasa.gov
Nature
|June 25, 2004
Summary
Humanity
Area of Science:
- Ecology
- Environmental Science
- Human Ecology
Background:
- Human consumption significantly impacts Earth's ecosystems.
- Human appropriation of net primary production (HANPP) is a key metric for assessing this impact.
- HANPP affects biodiversity, atmospheric composition, and ecosystem services.
Purpose of the Study:
- To map global net primary production (NPP) demand and supply.
- To analyze the spatial variation of HANPP.
- To understand human dependence on NPP imports.
Main Methods:
- Global mapping of human-required NPP.
- Comparison of human NPP demand against landscape-generated NPP.
- Derivation of a spatial NPP supply and demand balance sheet.
Main Results:
- Human appropriation of net primary production varies widely across regions.
- Some areas appropriate significantly more NPP than locally produced.
- Analysis reveals uneven global consumption footprints and NPP import dependencies.
Conclusions:
- Human consumption creates a spatially uneven impact on global ecosystems.
- Understanding NPP appropriation is crucial for sustainable resource management.
- Policy interventions can help mitigate future increases in HANPP.
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