break-of-bulk point, because many commodities delivered to such locations are
transported in bulk and often must be processed or refined. An example is crude
petroleum, which is delivered to ports utilizing enormous vessels called supertank-
ers. Some of the largest supertankers may carry up to 2 million barrels of oil,
nearly the entire daily demand of some smaller industrialized countries. The vast
volume of oil carried by these ships must be off-loaded and stored in large tanks,
before it is moved by pipeline to refineries where it is made into heating oil, gaso-
line, and other petroleum products.
Physical barriers also can serve as break of bulk points. This was the case in the
early urban development of the eastern United States, when streams were used to
penetrate the interior of the region. As larger ships moved upstream, they typically
encountered rapids or waterfalls at a point where the streambed crossed an abrupt
change in elevation. This point where the elevation changed is known as the fall
line, indicating the imaginary line in the eastern United States separating the Gulf
Atlantic Coastal plain from the Piedmont, a region of rolling hills and rugged ter-
rain. At the fall line, a change in the mode of transportation was required—in this
case, moving goods from a larger ship to smaller barges or canoes to send the cargo
further upstream. Because a change in the means of transport was needed that
required shifting products from vessels of larger bulk to smaller carriers, storage
and processing facilities were also typically required at the point of the fall line
alongstreams.Thisledtotheagglomerationof economic activities at the break
of bulk location, and the subsequent development of urban centers, as labor and
capital were drawn to these points. Break-of-bulk points, especially port cities, tend
to develop into industrial centers since there is always an additional cost involved
when transferring to a different means of transport. This is especially true in the case
of bulk commodities like petroleum, iron ore, coal, etc. Thus, break-of-bulk loca-
tions frequently develop into processing centers for raw materials, as it is more cost
effective to refine the materials into higher-value products at that location rather
than transport them further in unprocessed form. Finally, break-of-bulk points
may be established by changes in political space, such as at a border crossing, where
legal limits on the weight of bulky cargos force division into smaller parcels.
Buffer Zone
A buffer zone is a space placed between two or more locations increasing the
degree of spatial distance between them. In effect, a buffer zone functions as a
geographic insulator, separating zones of differing use, various regions, or coun-
tries that may potentially be in conflict from one another. They may be created
Buffer Zone 41