Utilization of Biomass in Mediterranean-Type Ecosystems: A Summary and Synthesis1

Botanist, Pacific Southwest Forest and Range Experiment Station, Forest Service, U.S. Department of Agriculture, Riverside, Calif. This session on the potential of Mediterraneantype ecosystems to supply biomass as a supplemental source of energy is a natural result of the present worldwide shortage of low-cost fuel. Some of these ecosystems are highly productive, partly because the summer drought is modified by dense fog which reduces the normal maximum air temperature to less than 25° C. Also, wet-season precipitation approaches 1000 mm. Biomass from such ecosystems is often used for sawtimber, and only residue is available for energy. At the other extreme of Mediterranean climate, marine air influence is low and the dry season is hot and nearly devoid of any form of precipitation. Under these conditions, most of the presently available methods of biomass processing may use as much energy as the biomass can provide.