Robin L. Chazdon, Braulio Vilchez Alvarado, Susan G. Letcher, Amanda Wendt, and U. Uzay Sezen
- Published in print:
- 2014
- Published Online:
- September 2014
- ISBN:
- 9780226322667
- eISBN:
- 9780226024134
- Item type:
- chapter
- Publisher:
- University of Chicago Press
- DOI:
- 10.7208/chicago/9780226024134.003.0011
- Subject:
- Biology, Biodiversity / Conservation Biology
Human activities superimpose complexity onto spatially and temporally variable successional processes. Biotic and anthropogenic legacies of land-use transitions and forest regrowth are intricately ...
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Human activities superimpose complexity onto spatially and temporally variable successional processes. Biotic and anthropogenic legacies of land-use transitions and forest regrowth are intricately connected through effects of landscape suitability for crop cultivation or pasture establishment; these phenomena strongly affect rates and scale of land clearing for agriculture, duration of land use, rates of agricultural abandonment, and seedling establishment following abandonment. Studies in the Old and New World tropics have documented pervasive, long-term human impacts on species composition and forest structure in tropical secondary forests. The rate, structure, and composition of forest regrowth are strongly affected by soil disturbance, residual vegetation, and proximity to seed sources. Long-term effects emerge from cascading effects of initial abundance, composition, and spatial patchiness of species that colonize abandoned agricultural areas. Thus secondary forests are particularly sensitive to human impacts and land use intensity. This chapter analyzes five major ways in which human activities influence secondary forest regeneration in Costa Rica and presumably other regions of the wet tropics: (1) remnant trees in pastures; (2) hunting and density of mammalian seed predators; (3) duration and intensity of agricultural land use; (4) landscape structure and distribution of forest patches; and (5) invasion of exotics.Less
Human activities superimpose complexity onto spatially and temporally variable successional processes. Biotic and anthropogenic legacies of land-use transitions and forest regrowth are intricately connected through effects of landscape suitability for crop cultivation or pasture establishment; these phenomena strongly affect rates and scale of land clearing for agriculture, duration of land use, rates of agricultural abandonment, and seedling establishment following abandonment. Studies in the Old and New World tropics have documented pervasive, long-term human impacts on species composition and forest structure in tropical secondary forests. The rate, structure, and composition of forest regrowth are strongly affected by soil disturbance, residual vegetation, and proximity to seed sources. Long-term effects emerge from cascading effects of initial abundance, composition, and spatial patchiness of species that colonize abandoned agricultural areas. Thus secondary forests are particularly sensitive to human impacts and land use intensity. This chapter analyzes five major ways in which human activities influence secondary forest regeneration in Costa Rica and presumably other regions of the wet tropics: (1) remnant trees in pastures; (2) hunting and density of mammalian seed predators; (3) duration and intensity of agricultural land use; (4) landscape structure and distribution of forest patches; and (5) invasion of exotics.
