What determines geographical patterns of the global human appropriation of net primary production?

Abstract

The human appropriation of net primary production (HANPP) is an integrated socioecological indicator of the intensity of land use. HANPP is associated with changes in global biogeochemical cycles of carbon, water, nitrogen and other substances as well as in ecosystem functions, services and biodiversity. Understanding patterns in HANPP is therefore important for the integrated analysis of the global land system. Attempts to explain spatial patterns of HANPP need to take both socioeconomic and natural factors as well as their interaction into account. In order to contribute to the understanding of global geographical patterns of HANPP, we discuss here the statistical analysis of a global national-level data set that includes data on HANPP and its components as well as selected potential determinants of HANPP for the year 2000. This statistical analysis is complemented with a discussion of findings from long-term country-level case studies conducted by ourselves and our students. We find that HANPP is higher in naturally more productive countries. Population density emerges as the most powerful factor determining HANPP per unit area and even has a strong influence on national-level patterns in per-capita HANPP. The interrelation between HANPP and economic growth or development is complex. On the one hand, growing affluence is associated with richer diets and other consumption patterns that tend to drive up HANPP, but on the other hand, economic growth is also associated with growing biomass trade as well as technological innovations that can help to reduce the amount of HANPP caused per unit of biomass consumption. While drawing some preliminary conclusions from our analysis, we also underline the necessity for further research