Geography Reference
In-Depth Information
of such outcomes may be devastating for commercial logging as well as wildlife habitat and
recreation. Loss of vegetation results in decreases in the maze of root systems that hold soil
in place, perhaps leading to erosion and mudslides. In addition, the acid may also have a fatal
effect on bacteria and microbes that break down organic nutrients in the topsoil and contribute
to soil fertility. Thus, acid rain may have a harmful effect on both the quality and quantity of
soil.
Aquatic impacts:
Acid rain runoff may adversely impact streams, rivers, lakes, and
oceans. Aquatic plants may be affected in the same manner as terrestrial ones. If they die, so
does habitat for all kinds of animal species, as well as potentially significant elements in food
chains. In addition, fish and other animal species may perish directly from prolonged exposure
to the acids, or indirectly from silt laden runoff attendant to loss of roots that held soil in place.
Small lakes that collect runoff, but have no outlet, are particularly susceptible to harm. Liter-
ally and figuratively, they are dead ends, the final collecting place for acid rain. Acid concen-
trations may be such that lakes become, for all intents and purposes, sterile.
Estuaries may also be impacted, and with them, marine fisheries. The problem here is not so
much the acid as the nitrates, a favorite of algae. The impact of that, as was discussed earlier
in the chapter in the case of the Chesapeake Bay, may be fish kills on a significant scale.
Material impacts:
Material impacts principally concern deterioration of stonework and
statuary
(sculptures and statues), particularly ones made of marble. The corrosive effect of
acid rain may literally eat away at these to the point where — to use an admittedly extreme
example — statues become undistinguishable slabs of rock. Building facades are of more im-
mediate importance, and thousands of them around the world are slowly dissolving.
Figure 18-4:
The
acid rain that
destroys forests
and contami-
nates lakes
largely originates
in personal, com-
mercial, and in-
dustrial
consump-tion of
fossil fuels.
Applied Geography: Watershed management
A
watershed
is an area that drains into a river, lake, bay, or reservoir. As we saw with
the case of the Chesapeake Bay, the quality of a body of water may be intimately related
