Document: RIC-3-99-111

Spatial models as an emerging foundation of road system ecology and a handle for transportation planning.

FORMAN, R.T.T.*

Harvard University, Cambridge, MA 02138 USA ¹

Abstract:
As transportation-related environmental issues and public concern rapidly grow, a science of road system ecology stirs. Simple spatial models appear particularly promising to link ecological flows and patterns across the landscape with engineering dimensions immediately around a road. Eight useful examples gleaned from road systems worldwide, as well as from theory, are introduced: 1) Perforated roadbeds help overcome the barrier effect by enhancing the crossing of animals and water; 2) giant green network provides connectivity and biological diversity in intensive-agriculture landscapes; 3) shrinking populations model links habitat loss, roadkill, edge effect, disturbance, and the subdividing barrier effect of a road; 4) road-effect zone delineates the ecologically minimum area for transportation planning; 5) network-and-node theory combines routes and destinations, both varying in size, traditionally for transport economics; 6) road density/mesh size links diverse effects from mammals to fire and water; 7) network variability links network form and nature's variability; and 8) ecological road fitting pinpoints the arrangement of interactions with streams, slopes, corridors, patches and species. In addition to representing a growing foundation of theory for road system ecology, such spatial models offer visual and conceptual simplicity to stimulate collaboration among ecologists, engineers, economists, the public and policy makers. Better road systems, which provide for safe and efficient transport and also provide effectively for ecological flows and species diversity, should emerge.

Keywords: transportation, road systems

This abstract is being presented at: 5:00 PM in session:
Oral Session #51: Disturbance Ecology: Harvesting, Grazing and Roads.