flood gif animation

Flooding at Red Hill

The floodplain deposits at Red Hill indicate that they were subject to cycles of wetting and drying. In other words, they appear to have been subject to periodic and perhaps seasonal flooding. We can't be certain that this flooding occurred on an seasonal basis, but such would be consistent with the highly seasonal pattern of rainfall predicted by climatic models of the Late Devonian Catskill Delta.

Seasonal flooding is a defining feature of many modern lowland rivers not regulated by humans. Seasonal increases in streamflows—often, but not always caused seasonal increases in rainfall—result in gradual and predictable increases in water levels and the inundation of floodplains. This inundation, in turn, creates a bonanza for both the river and its floodplains.

Flooding is the primary mechanism by which organic matter is transferred from the floodplain to the river. Part of this flood-mediated transfer is achieved via physical transport. In other words, the floodwaters literally carry wood, leaf litter, soil invertebrates, bacteria and dissolved nutrients back into the river. But the transfer is also achieved through the activity of many river-dwelling animals. Instead of waiting for the goodies to come to them, they go to the floodplain.

This is especially true of the fishes. In fact, spawning for many fishes is keyed to seasonal flooding. Linking reproduction with flooding can increase the chances that their young will have more food. These floodplain nurseries also increase their chances to avoid predation because they offer greater habitat area and more hiding sites than the river channel.

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Scientific Papers:
Beerbower, J.R. 1985. "Early development of continental ecosystems." pp. 47-92. In: B.H. Tiffney (ed.), Geological Factors and the Evolution of Plants. Yale Univ. Press: New Haven.
Beerbower, J.R., J.A. Boy, W.A. DiMichele, R.A. Gastaldo, R. Hook, N. Hotton, III, T.L. Phillips, S.E. Scheckler, and W.A. Shear. 1992. "Paleozoic terrestrial ecosystems." pp. 205-235. In: A.K.Behrensmeyer, J.D. Damuth, W.A. DiMichele, R.Potts, H.-D. Sues and S.L. Wing (eds.) Terrestrial Ecosystems throught Time. Chicago: Univ. Chicago Press.
Gensel , P.G. and D. Edwards (eds.). 2001 Plants Invade the Land: Evolutionary and Environmental Approaches. New York: Columbia Univ. Press.
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The flooding animation is copyrighted © 2002, Dennis C. Murphy, (see Terms of Use).

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