Geography Reference
In-Depth Information
HOGS AND PIGS IN THE
UNITED STATES, 2007
One dot represents 20,000 hogs and pigs
The United States total is 67,786,318
0
400
600
800
10 0 0 Kilometers
200
0
200
400
600 Miles
Modified after publication 07-M149 U.S. Department of Agriculture,
National Agricultural Statistics Service.
ALASKA
HAWAI'I
Figure 11.22
Hogs and Pigs in the United States, 2007.
Courtesy of: United States Census of Agriculture, National
Agricultural Statistics Service.
cod fi sheries on Canada's Grand Banks off Newfoundland
collapsed. In 1975 biologists estimated the Atlantic blue-
fi n tuna population at 250,000; today the western stock is
listed as critically endangered, and the stock in the
Mediterranean is listed as endangered. From ocean
perch and king crabs off Alaska to rock lobsters and
roughies off New Zealand, fi sh and shellfi sh populations
are depleted. The total annual catch is also declining and
may already be beyond the point of recovery. Much of
the damage has already been done, and fi shing industries
in many parts of the world have reported dwindling har-
vests and missing species.
If you travel to Mediterranean Europe today you will
see a landscape that refl ects the clearing of forests in
ancient times to facilitate agriculture and trade. Look
carefully at many hillslopes and you will see evidence of
terraces cut into the hills many centuries ago. The indus-
trialization and commercialization of agriculture has
accelerated the pace and extent of agriculture's impact on
the environment in recent times. More land has been
cleared, and the land that is under cultivation is ever more
intensively used.
Signifi cant agriculturally driven changes to the envi-
ronment go far beyond the simple clearing of land. They
range from soil erosion to changes in the organic content
of soils to the presence of chemicals (herbicides, pesti-
cides, even antibiotics and growth hormones from live-
stock feces) in soils and groundwater. In places where
large commercial crop farms dominate, the greatest con-
cerns often center on the introduction of chemical fertil-
izers and pesticides into the environment—as well as soil
erosion. And, as we have seen, the movement toward
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