On the carbon cycle impact of combustion of harvested plant biomass vs. fossil carbon resources

摘要

This work examines the comparative impact on the carbon cycle, of harvested plant biomass combustion vs. fossil carbon combustion. A common carbon cycle model is shown to possess limitations and inconsistencies that lead to physically unrealistic predictions. The model is modified, so as to incorporate harvested biomass combustion as an energy resource, and the dependence of the photosynthesis rate on leaf area, rather than vegetated land area. The newly proposed model is validated with fossil fuel usage and atmospheric CO_2 concentration data, since the beginning of the industrial revolution. Although, biomass is generally considered to be a green energy source, it is shown in this work that biomass burning may result in a higher, long term, CO_2 atmospheric concentration than fossil carbon burning, depending on the rate of burning and reforestation intensity. A close examination of the characterization of harvested biomass as a renewable energy source is warranted.