Environmental Engineering Reference
In-Depth Information
Aldo Leopold wrote in his 1933 textbook titled Game Management that “game can be restored by
the creative use of the same tools which have heretofore destroyed it-ax, plow, cow, ire, and gun.”
Similarly, lakes can undergo a natural succession, the classical view of which is that lakes are
temporary ecological systems, formed in some depression that will eventually ill in to become a
terrestrial environment, or become extinct. The stages of succession that a lake will go through,
and the rate of succession, are a function of the loads of water, nutrients and sediment that the lake
receives. But, the natural process of succession will be for a lake to eventually form a pond, then a
marsh, then a meadow, and eventually dry land (Figure 16.3).
As George E.P. Box wrote, “essentially, all models are wrong, but some are useful” (Box and
Draper 1987). Similarly, the concept of lake aging is a useful tool, but that aging (succession) is not
necessarily an inevitable and irreversible process.
16.2.2 f actorS a ffectInG S ucceSSIon
The origin of the concept of lake succession is often attributed to Jean André Deluc, who, in Volume 1
of his topic Geological Travels in Some Parts of France, Switzerland, and Germany , published in
1810, described six stages in the transformation of a lake into a peaty meadowland. Deluc also indi-
cated that the rate of succession is greatest on shallow shores, and the process of change is almost
nonexistent on steep shores.
From Deluc's analyses, lakes with littoral zones (Figure 16.4) will have greater rates of succes-
sion than those with only a pelagic zone. Or, as lakes age and ill, the littoral zone will become
FIGURE 16.3
Stages of succession in a small lake. (From Kidish, http://www.kidish.bc.ca/.)
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