Geoscience Reference
In-Depth Information
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Figure 2-3.
Traditional small boats suitable for wetlands and shallow water. A. Vertical view of Innuit kayak in
coastal water of southwestern Greenland. Photo taken from a helicopter; courtesy of P. Jensen. B. Boy in small
wooden canoe, Amazonia, Brazil. Photo courtesy of K. Buchele.
Figure 2-4.
Panorama of the Blue Lake hot spring and marsh complex in the desert basin of western Utah, United
States. The boardwalk and dock in lower center provide access for scuba divers to enter the deep pool. Fresh water
in the foreground becomes highly saline in the background. View toward southeast. Photo taken from a model
airplane; courtesy of B. Graves.
lowlands, because of abundant water supply.
Alpine wetlands are also fairly common, as
mountains typically receive more precipitation
than do adjacent lowlands. Even deserts have
wetlands supported by drainage from adjacent
mountains, ground-water discharge, or infre-
quent storm runoff (Fig. 2-6). Much of the circum-
arctic region turns to wetland during the brief
period of summer melting. This rich diversity of
wetland environments requires a l exible dei ni-
tion in terms of water conditions.
2.3 Soil
Soils are characterized by frequent, prolonged
saturation and low oxygen content, which give
rise to anaerobic chemical environments where
