Forest regeneration in a chronosequence of tropical abandoned pastures: Implications for restoration ecology

Aide TM, Zimmerman JK, Pascarella JB, Rivera L, Marcano-Vega H

RESTORATION ECOLOGY
8 (4): 328-338 DEC 2000

Abstract:
During the mid-1900s, most of the island of Puerto Rico was deforested, but a shift in the economy from agriculture to small industry beginning in the 1950s resulted in the abandonment of agricultural lands and recovery of secondary forest. This unique history provides an excellent opportunity to study secondary forest succession and suggest strategies for tropical forest restoration. To determine the pattern of secondary succession, we describe the woody vegetation in 71 abandoned pastures and forest sites in four regions of Puerto Rico. The density, basal area, aboveground biomass, and species richness of the secondary forest sites were similar to those of the old growth forest sites (>80 yr) after approximately 40 years. The dominant species that colonized recently abandoned pastures occurred over a broad elevational range and are widespread in the neotropics. The species richness of Puerto Rican secondary forests recovered rapidly, but the species composition was quite different in comparison with old growth forest sites, suggesting that enrichment planting will be necessary to restore the original composition. Exotic species were some of the most abundant species in the secondary forest, but their long-term impact depended on life history characteristics of each species. These data demonstrate that one restoration strategy for tropical forest in abandoned pastures is simply to protect the areas from fire, and allow natural regeneration to produce secondary forest. This strategy will be most effective if remnant forest (i.e., seed sources) still exist in the landscape and soils have not been highly degraded. Patterns of forest recovery also suggest strategies for accelerating natural recovery by planting a suite of generalist species that are common in recently abandoned pastures in Puerto Rico and throughout much of the neotropics.

Author Keywords:
Caribbean, exotics, secondary succession, tropics

KeyWords Plus:
PUERTO-RICO, RAIN-FOREST, SECONDARY FORESTS, RECOVERY, SUCCESSION, AMAZONIA, MANAGEMENT, HURRICANE, PATTERNS, COLOMBIA

Addresses:
Aide TM, Univ Puerto Rico, Dept Biol, POB 23360, Rio Piedras, PR 00931 USA
Univ Puerto Rico, Dept Biol, Rio Piedras, PR 00931 USA
Univ Puerto Rico, Inst Trop Ecosyst Studies, San Juan, PR 00936 USA
Valdosta State Univ, Dept Biol, Valdosta, GA 31698 USA
Univ Puerto Rico, Dept Biol Sci, Rio Piedras, PR 00931 USA

Publisher:
BLACKWELL SCIENCE INC, 350 MAIN ST, MALDEN, MA 02148 USA

IDS Number:
385FR

ISSN:
1061-2971