Fueling the Source: Mapping and Modeling Carbon and Woody Resources for Continental Africa

摘要

Complex interactions among climate change and ecosystem processes (plant demographics, tree-grass interactions, grazers, browsers, fire and nitrogen) challenge our ability to predict future carbon stocks in Africa and other tropical regions. Recent work suggests Africa has a near zero decade-scale carbon balance, but that climate fluctuations induce sizeable variability in ecosystem productivity and savanna fires, greatly enhancing the inter-annual variability in global atmospheric [CO_2]. If, indeed, Africa's net biogenic carbon balance is near-zero, this also has profound implications for the socioeconomically and culturally vital availability and sustainable harvest of wood and charcoal for fuel. We present remote sensing based woody biomass assessments for sub-Saharan Africa (SSA) using a combination of optical and radar datasets, and spatially explicit estimates of fuel-wood demand derived from country-scale statistics. We describe a simplified, low-dimensional model of African ecosystems and use it to explore carbon and fuel-wood dynamics in response to climate variability and disturbance factors.