Lake Production, Succession, and Eutrophication - Hydro-Environmental Analysis: Freshwater Environments - page 454

Littoral zone Pelagic zone Littoral zone

Mixed
layer

Photic zone

Aphotic
zone

Profundal
zone

Compensation depth
(photosynthesis = respiration)

FIGURE 16.4 Lake zones.

increasingly dominant. Hutchinson (1975) noted that “zonation, therefore, is taken to be the spatial
equivalence of succession in time, even in the absence of change.”

16.2.3 L ake o ntoGeny and S taGeS of S ucceSSIon
Lake ontogeny refers to the successional development of inland aquatic systems (Wetzel 2001).
Ontology has multiple meanings, depending on the discipline to which the term is applied, such as
to science or philosophy. One of its common scientiic meanings refers to the growth of communi-
ties or organisms. One well-known use is in the theory of recapitulation, also called the biogenetic
law or embryological parallelism—often expressed as “ontogeny recapitulates phylogeny.” This
hypothesis is that in developing from an embryo to an adult, animals undergo stages of development
that have strong parallels with the development of their ancestors, thereby representing or resem-
bling the stages of succession (or evolution).
Populations also undergo stages of growth, as illustrated by an idealized sigmoid (S-shaped) growth
curve (Figure 16.5). Generally, when an area is irst colonized, there is a period of acclimation when
the population growth is slow, called the lag phase. Once acclimated, the rate of increase accelerates,
with growth eventually becoming exponential. At some point, the population will approach the car-
rying capacity and as food or habitat becomes limiting, the rate of acceleration will decrease and the
population will become stable, or will luctuate around the carrying capacity in a dynamic equilibrium.
Hutchinson and Wollack (1940) stressed parallels between the early development of lake com-
munities and the sigmoid growth phase of animal communities, such as the zooplankton in Linsley
Pond, Connecticut. They implied that the apparent early developmental processes in lakes were
dominated by colonization effects, the lag phase.
One of the most common schemes used to characterize lake ontogeny is one where lakes progres-
sively develop through the following trophic (derived from Greek and meaning food or feeding) stages:

• Oligotrophic, which means “scant or lacking”

• Mesotrophic, which means “midrange”

• Eutrophic, which means “good or suficient”

• Hypereutrophic, which means “over abundant” (Florida LakeWatch 2002).

The concept was introduced by Naumann (1919; Figure 16.6, cited by Wetzel 2001), who used
oligotrophy and eutrophy to distinguish lakes based on their phytoplankton populations. Naumann's