The first study of Human Appropriation of Net Primary Productivity (HANPP) was conducted by Vitousek and others in 1986. Since then, many researchers, most of whom are from the Institute of Social Ecology in Vienna, Austria, have studied HANPP. HANPP is associated with socioeconomic and natural processes and serves as an assimilated socio ecological indicator that quantifies the impacts of human-induced productivity change and ecological biomass flow. HANPP is the measure of human dependence on the potential productivity of ecosystems for provisioning ecological services like food, fiber and fuel. For this reason, HANPP captures the ecological footprint of human economies well. Therefore, this research will quantify and map HANPP at the county level for the U.S., accounting for the production of major crops over the last fifty years in order to capture human dependence on ecological resources. To the harvest and yield data from United States Department of Agriculture – National Agricultural Statistics Services were applied required variables like dry fraction, harvest index, carbon content and percent shoot. Finally, this exercise will explore the spatial and temporal dynamics and trends in American ecological footprints that are embedded within economic production, trade and consumption with the objective to reveal how HANPP is a critical component of the U.S. food-energy-water (FEW) system.
Results/Conclusions
Preliminary results show that HANPP of all the U.S. major crops considered for the study had increased remarkably from 1960 to 2017 due to vigorous increases in yields. Future work will similarly calculate HANPP for livestock grazing and timber production to estimated total HANPP harvested. From there, a study of teleconnections between HANPP and eHANPP (HANPP embodied in trade) at the county scale for the U.S. will be conducted.