Unique study analyses consumption and carrying capacity of ecosystems
How does the spatial distribution of human consumption of carbon (as embodied in food, fiber, and wood/biofuel products) compare to the ability of land-based ecosystems to produce it? This is an important question, the answer to which may yield insights into the bioenergy production potential of different regions of the planet. Ecosystems that can easily and sustainably meet the 'food-fiber-fuel' needs of their populations, can become bioenergy exporters, whereas others will be forced to import.
A unique study - titled 'Human Appropriation of Net Primary Productivity (HANPP)' - led by Marc Imhoff and Lahouari Bounoua of the NASA Goddard Space Flight Center (GSFC) has attempted to answer this question by spatially allocating the amount of carbon required to derive food and fiber products consumed by humans. Columbia University's Center for International Earth Science Information Network (CIESIN) puts a combination of the results - published between 2004 and 2006 - under the spotlight.
Carrying capacity
Using United Nations data on food and fiber consumption, the scientists allocated it on a per capita basis to SEDAC's Gridded Population of the World dataset. The scientists compared this to a remotely-sensed map of global net primary productivity (NPP) — the net amount of solar energy converted to plant organic matter through photosynthesis — in order to identify parts of the world where local NPP is oversubscribed. The map (click to enlarge) shows how, in some urban areas, the excess of consumption over local NPP production is more than 1,000% (areas in dark red). In others, the ecosystem's maximum sustainable carrying capacity is far from reached.
Human appropriation of net primary productivity (HANPP), through the consumption of food, paper, wood, fuel and fiber, alters the composition of the atmosphere, levels of biodiversity, energy flows within food webs and the provision of important ecosystem services. Importantly for us, it also determines the sustainability of bioenergy production, and the carrying capacity of ecosystems to yield biomass and biofuels for exports:
biomass :: bioenergy :: biofuels :: energy :: ecosystem :: net primary productivity :: carrying capacity :: biofuels :: biomass :: sustainability ::
A tabular database associated with the spatial data also describes human requirements for NPP by country and major product: vegetable calories, meat, eggs, milk, fiber, paper, and wood. Globally, meat consumption accounts for 47% of NPP requirements for human food and 17% of overall NPP requirements. But these percentages vary significantly by country. For instance, meat consumption in the United States accounts for 68% of NPP requirements for human food and 23% of overall NPP requirements as opposed to Bangladesh (the country consuming the least amount of meat) where the percentages are 8% and 3%, respectively.
The spatial data products plus the tabular data are available from the HANPP Web site, which is part of the SEDAC Environmental Sustainability mission area.
Bioenergy potential of regions
Researchers from the International Energy Agency's Bioenergy Task 40 used virtually similar methods to calculate the sustainable biofuel and export potential in different regions of the planet (earlier post). The results clearly match those of the NPP-study.
Two regions stand out with their vast capacity to produce biofuels without exceeding the carrying capacity of their ecosystems, which are also needed to provide food, fiber and fuel to (growing) local populations: Latin America and sub-Saharan Africa. Zones with limited potential are the Indian subcontinent, China and the Far East, Europe, Eastern North-America and the Middle East. Not surprisingly, some of these regions already are net bioenergy importers (Europe, China and especially Japan which has been linking up with Brazil for biofuel supplies), and will become so increasingly in the future.
The original work on these data was published in Nature and Journal of Geophysical Research.
More information:
Columbia University's SEDAC: Human Appropriation of Net Primary Productivity (HANPP) website.
Imhoff, Marc L., Lahouari Bounoua, Taylor Ricketts, Colby Loucks, Robert Harriss, and William T. Lawrence. 2004. Global patterns in human consumption of net primary production. Nature, 429, 24 June 2004: 870-873.
Imhoff, Marc L., and Lahouari Bounoua. 2006. Exploring global patterns of net primary production carbon supply and demand using satellite observations and statistical data. Journal of Geophysical Research, 111, D22S12, doi:10.1029/2006JD007377.
A unique study - titled 'Human Appropriation of Net Primary Productivity (HANPP)' - led by Marc Imhoff and Lahouari Bounoua of the NASA Goddard Space Flight Center (GSFC) has attempted to answer this question by spatially allocating the amount of carbon required to derive food and fiber products consumed by humans. Columbia University's Center for International Earth Science Information Network (CIESIN) puts a combination of the results - published between 2004 and 2006 - under the spotlight.
Carrying capacity
Using United Nations data on food and fiber consumption, the scientists allocated it on a per capita basis to SEDAC's Gridded Population of the World dataset. The scientists compared this to a remotely-sensed map of global net primary productivity (NPP) — the net amount of solar energy converted to plant organic matter through photosynthesis — in order to identify parts of the world where local NPP is oversubscribed. The map (click to enlarge) shows how, in some urban areas, the excess of consumption over local NPP production is more than 1,000% (areas in dark red). In others, the ecosystem's maximum sustainable carrying capacity is far from reached.
Human appropriation of net primary productivity (HANPP), through the consumption of food, paper, wood, fuel and fiber, alters the composition of the atmosphere, levels of biodiversity, energy flows within food webs and the provision of important ecosystem services. Importantly for us, it also determines the sustainability of bioenergy production, and the carrying capacity of ecosystems to yield biomass and biofuels for exports:
biomass :: bioenergy :: biofuels :: energy :: ecosystem :: net primary productivity :: carrying capacity :: biofuels :: biomass :: sustainability ::
A tabular database associated with the spatial data also describes human requirements for NPP by country and major product: vegetable calories, meat, eggs, milk, fiber, paper, and wood. Globally, meat consumption accounts for 47% of NPP requirements for human food and 17% of overall NPP requirements. But these percentages vary significantly by country. For instance, meat consumption in the United States accounts for 68% of NPP requirements for human food and 23% of overall NPP requirements as opposed to Bangladesh (the country consuming the least amount of meat) where the percentages are 8% and 3%, respectively.
The spatial data products plus the tabular data are available from the HANPP Web site, which is part of the SEDAC Environmental Sustainability mission area.
Bioenergy potential of regions
Researchers from the International Energy Agency's Bioenergy Task 40 used virtually similar methods to calculate the sustainable biofuel and export potential in different regions of the planet (earlier post). The results clearly match those of the NPP-study.
Two regions stand out with their vast capacity to produce biofuels without exceeding the carrying capacity of their ecosystems, which are also needed to provide food, fiber and fuel to (growing) local populations: Latin America and sub-Saharan Africa. Zones with limited potential are the Indian subcontinent, China and the Far East, Europe, Eastern North-America and the Middle East. Not surprisingly, some of these regions already are net bioenergy importers (Europe, China and especially Japan which has been linking up with Brazil for biofuel supplies), and will become so increasingly in the future.
The original work on these data was published in Nature and Journal of Geophysical Research.
More information:
Columbia University's SEDAC: Human Appropriation of Net Primary Productivity (HANPP) website.
Imhoff, Marc L., Lahouari Bounoua, Taylor Ricketts, Colby Loucks, Robert Harriss, and William T. Lawrence. 2004. Global patterns in human consumption of net primary production. Nature, 429, 24 June 2004: 870-873.
Imhoff, Marc L., and Lahouari Bounoua. 2006. Exploring global patterns of net primary production carbon supply and demand using satellite observations and statistical data. Journal of Geophysical Research, 111, D22S12, doi:10.1029/2006JD007377.
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