"In physics, the second law of thermodynamics, which deals with the natural flow of energy distribution…stipulates that localized 'systems,' (think of an ice cube melting), will disperse outward, unless a counter force is applied to contain it. In population centers of the country, urban sprawl and resource depletion are the natural consequences of increasing populations (the melting ice cube), unless countervailing forces (land use laws) are effectively applied to manage growth, and protect finite resources."
- Cooking Up A Story
You may not have heard much about it yet, but in the Portland metro area there's a big discussion going on, called the Reserves Process, about how much land will be allocated for development and how much will be set aside for agricultural use and open space. This process will directly affect the small farmers in the Willamette Valley who provide much of the local food you see at farmers' markets and stores.
This video by my friend Rebecca at Cooking Up a Story gives a good outline of the major points of the debate. Read the full post on the issue here.