Secondary forests constitute a substantial proportion of tropical forestlands. These forests occur on both public and private lands and different underlying environmental variables and management regimes may affect post-abandonment successional processes and resultant forest structure and biodiversity. We examined whether differences in ownership led to differences in forest structure, tree diversity, and tree species composition across a gradient of soil fertility and forest age. We collected soil samples and surveyed all trees in 82 public and 66 private 0.1-ha forest plots arrayed across forest age and soil gradients in Guanacaste, Costa Rica. We found that soil fertility appeared to drive the spatial structure of public vs. private ownership; public conservation lands appeared to be non-randomly located on areas of lower soil fertility. On private lands, areas of crops/pasture appeared to be non-randomly located on higher soil fertility areas while forests occupied areas of lower soil fertility. We found that forest structure and tree species diversity did not differ significantly between public and private ownership. However, public and private forests differed in tree species composition: 11 percent were more prevalent in public forest and 7 percent were more prevalent in private forest. Swietenia macrophylla, Cedrela odorata, and Astronium graveolens were more prevalent in public forests likely because public forests provide stronger protection for these highly prized timber species. Guazuma ulmifolia was the most abundant tree in private forests likely because this species is widely consumed and dispersed by cattle. Furthermore, some compositional differences appear to result from soil fertility differences due to non-random placement of public and private land holdings with respect to soil fertility. Land ownership creates a distinctive species composition signature that is likely the result of differences in soil fertility and management between the ownership types. Both biophysical and social variables should be considered to advance understanding of tropical secondary forest structure and biodiversity.
Bibliographical noteFunding Information:
We are grateful to Devon Nemire-Pepe, Rebecca Orrison, Juan Deshayes-López, Daniel Pérez-Aviles, and Maria Gei for their invaluable field help. We thank Jennifer Powers for contributing key ideas to this project; sharing public forest data; commenting on drafts of the manuscript; and providing logistical, in-kind, and financial support. Funding for the public forest dataset was provided by a NASA New Investigator Award to Jennifer Powers. We thank Daniel Chavez and Valerie Carranza for editing the Spanish abstract. We thank JeriLynn Peck for her valuable advice on ordination techniques. We thank Saara DeWalt and anonymous reviewers for their helpful suggestions. The lead author gratefully acknowledges the following funding sources: Fulbright Fellowship, The Garden Club of America Award in Tropical Botany, Crosby Fellowship, University of Minnesota Interdisciplinary Doctoral Fellowship at the Institute on the Environment, and University of Minnesota Plant Biological Sciences Departmental Fellowship.
© 2018 The Association for Tropical Biology and Conservation
Copyright 2018 Elsevier B.V., All rights reserved.
- Costa Rica
- ecosystem services
- forest biomass
- forest conservation
- forest management
- forest succession
- land tenure
- secondary forests
- species composition