Forest regeneration in abandoned coffee plantations and pastures in the Cordillera Central of Puerto Rico
2002
Marcano-Vega, H. | Aide, T.M. | Baez, D.
Forest structure and species composition were described in abandoned shade and sun coffee plantations and abandoned pastures in Puerto Rico. Forest structural characteristics were similar to older forest sites after approximately 30 yr of recovery. The historical presence of shade coffee plantations as the dominant agricultural activity in the region has resulted in the homogenization of secondary forest composition. The continuous dominance of Coffea arabica and species used for shade in abandoned shade coffee contributed to a slower rate of species composition change in comparison to abandoned pastures. Abandoned pastures were initially colonized by a group of light demanding and/or wind dispersed species and then by shade tolerant species characteristic of abandoned shade coffee plantations, suggesting that the secondary forests of abandoned shade coffee plantation are the major source of species in this landscape. The presence of a few isolated big trees in sun coffee plantations appeared to facilitate colonization of woody species similar in composition to abandoned shade coffee plantations. In a multivariate analysis, time since abandonment and elevation were the variables that explained the majority of variability in species composition among sites. However, a few native species (e.g. Guarea guidonia, Casearia sylvestris, Ocotea leucoxylon) were common regardless of land use history or elevation. In contrast, important old forest species (e.g. Sloanea berteriana, Dacryodes excelsa, Manilkara bidentata) were rare or absent from most of the secondary forest stands suggesting the need to reintroduce these species. Land management and conservation efforts can be improved by incorporating the effects of land use history on secondary forest dynamics.
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