PARENT SESSION
Poster Session # 7: Restoration, Resource Management, and Conservation.
Monday, August 4 Presentation from 5:00 PM to 6:30 PM. SITCC Exhibit Hall B.
Global distribution of human NPP appropriation.
Imhoff, Marc1, Bounoua, Lahouari1, 2, Ricketts, Taylor3, 4, Loucks, Colby*,3, Harriss, Robert2, Lawrence, William5, 1 NASA Goddard Space Flight Center, Greenbelt, MD2 University of Maryland, College Park, MD3 World Wildlife Fund, Washington, DC4 Stanford University, Stanford, CA5 Bowie State University, Bowie, MD
ABSTRACT- Human population and consumption profoundly affect global ecosystems in numerous ways. One method of measuring the aggregate impact of human activities is to estimate the amount of total net primary production (NPP) we appropriate for our own use. While previous studies have estimated this fraction for the globe, here we develop spatially-explicit maps of both terrestrial NPP and of human NPP appropriation that allow spatial analysis of human impacts (based on a 0.25-degree grid). To estimate human appropriation, we multiply the population density of each grid cell by country-specific consumption factors, gleaned from FAO statistics and back-calculated to annual per capita mass of carbon consumed. We estimate global NPP to be 56.8 Pg C per year, and human NPP appropriation to be 9-20% of this total, both of which correspond reasonably well to previous global estimates. More importantly, the geographic distribution of NPP appropriation is extremely heterogeneous, due to global patterns of both population density and per capita consumption. In some areas, humans consume several times the local NPP ′supply,′ while in others we appropriate only a fraction of a percent of local NPP. In general, areas of high consumption do not correspond to the most productive regions of the world. Comparisons of NPP appropriation with global distribution of biodiversity indicate areas of maximum conflict between humans and other species for the products of photosynthesis.
Key words: conservation, global, npp, carbon