Document: GER-3-41-2

Prehistoric hurricane disturbance and forest regeneration in Nicaragua.

URQUHART, G.R.*

Michigan State University, East Lansing, MI 48825 ¹

Abstract:
Chronological difficulties for the study of ecology, posed by infrequent phenomena and slow processes, are overcome by the long-term coverage possible with paleoecological analyses. The regeneration of forests after a stochastic disturbance is a slow process beyond the scope of real-time study, but amenable to study with paleoecological techniques. To study the regeneration of tropical forests after hurricane damage, I analyzed a 5 m sediment core from a swamp lagoon in Nicaragua. The core covered the entire 8,000 year history of the swamp. X-rays revealed two sand layers deposited by hurricanes, one at 3300 y BP and the other c. 2000 y BP. Charcoal fragments and pollen analyses showed that the first of these layers was followed by fires and major changes in vegetation. This pattern was identical to that observed in the wake of Hurricane Joan, which struck in 1988 and left 90,000 ha of damaged swamp forest that burned shortly after. After the first prehistoric hurricane, forest vegetation did not return until 500 years later, due to repeated burning. This parallel event of the past illustrates a possible course for modern forest regeneration. As a counterpart to direct ecological analysis, fine-resolution paleoecological study can provide insight for the study of rare events and slow processes.

Keywords: paleoecology, hurricane, tropical forest, disturbance, fire, pollen

This abstract is being presented at: 2:30 PM in session:
Oral Session #32: Paleoecology.