Environmental Engineering Reference
In-Depth Information
would require 1,000-1,250 m
3
of fuel, or at least 12 times as much as went into
construction.
In the much warmer Piedmont, Italy's relatively cold northern province, the
annual preindustrial fuelwood consumption was close to 850 kg per capita or
(assuming 550 kg/m
3
) about 1.5 m
3
(Gales et al. 2005). A family of i ve thus needed
7-8 m
3
/year and would have burned more wood for heating than it used to build
its house in only about 10-15 years. Of course, these comparisons ignore important
qualitative differences (straight logs and better-quality woods are needed for con-
struction, while any woody phytomass, including fallen branches, bark, stumps, and
waste wood, made suitable fuel), but they make a critical point: fueling wooden
villages and even more so large wooden cities put a much greater strain on nearby
forests than did the initial construction. Moreover, it was one thing to import wood
from longer distances for what often amounted to a once-in-a-lifetime construction
project and another to rely on long-distance imports of fuelwood.
During the late nineteenth century and throughout the twentieth century, new
construction relied less on wood and more on structural steel and concrete, and
eventually also on aluminum and plastic materials. The United States and Canada
have been the only two Western countries where the building of single-family houses
continued to be dominated by wood (studs for frames, plywood for outer walls,
wooden roof trusses, joists, l oors, and staircases), but changing construction
methods and a greater reliance on other materials have reduced the specii c demand
for lumber, a trend that was partially countered by a steadily increasing size of an
average U.S. house (doubling from 110 m
2
in the early 1950s to 220 m
2
by 2005).
But wood for buildings has been far from the only market claiming large amounts
of wood as a raw material. After 1500, most of Europe's maritime societies engaged
in building large oceangoing l eets and navies, and this quest had translated into
high demand for quality timber. England was the best example of these needs, but
other maritime powers (France, Spain, Portugal, Holland) were not far behind. These
needs were notable because of greatly increased ship sizes. Typical seagoing vessels
remained small from antiquity throughthe Middle Ages, with hardly any growth
of typical displacements between the centuries of the early Roman Empire and
the time of the i rst, late medieval long-distance European voyages, made by the
Portuguese.
We have detailed information about wood requirements for different kinds of
vessels. The extremes are a single tree (for a dugout canoe or, after planking, for a
small boat) and a small forest of more than 6,000 oak trees needed to build the
largest (more than 100 guns) triple-deck warships of the i rst half of the nineteenth
