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Tropical forests are incredibly diverse in structure and function. Despite, or perhaps because of, this diversity, tropical biologists often conduct research exclusively in one or perhaps a few forest types. Rarely do we study the ecotone—the interstitial region between forest types. Ecotones are hyper-diverse, dynamic systems that control the flow of energy and organisms between adjacent ecosystems, with their locations determined by species’ physiological limits. In this review, we describe how studying ecotones can provide key indicators for monitoring the state of Neotropical forests from organisms to ecosystems. We first describe how ecotones have been studied in the past and summarize our current understanding of tropical ecotones. Next, we provide three example lines of research focusing on the ecological and evolutionary dynamics of the ecotone between tropical dry forests and desert; between tropical dry and rainforests; and between Cerrado and Atlantic rainforests, with the latter being a particularly well-studied ecotone. Lastly, we outline methods and tools for studying ecotones that combine remote sensing, new statistical techniques, and field-based forest dynamics plot data, among others, for understanding these important systems.
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This content will become publicly available on November 1, 2025
Climate and topography control variation in the tropical dry forest–rainforest ecotone
Abstract Ecotones are the transition zones between ecosystems and can exhibit steep gradients in ecosystem properties controlling flows of energy and organisms between them. Ecotones are understood to be sensitive to climate and environmental changes, but the potential for spatiotemporal dynamics of ecotones to act as indicators of such changes is limited by methodological and logistical constraints. Here, we use a novel combination of satellite remote sensing and analyses of spatial synchrony to identify the tropical dry forest–rainforest ecotone in Area de Conservación Guanacaste, Costa Rica. We further examine how climate and topography influence the spatiotemporal dynamics of the ecotone, showing that ecotone is most prevalent at mid‐elevations where the topography leads to moisture accumulation and that climatic moisture availability influences up and downslope interannual variation in ecotone location. We found some evidence for long‐term (22 year) trends toward upslope or downslope ecotone shifts, but stronger evidence that regional climate mediates topographic controls on ecotone properties. Our findings suggest the ecotone boundary on the dry forest side may be less resilient to future precipitation reductions and that if drought frequency increases, ecotone reductions are more likely to occur along the dry forest boundary.
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- Award ID(s):
- 2042453
- PAR ID:
- 10582817
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- Ecology
- Volume:
- 105
- Issue:
- 11
- ISSN:
- 0012-9658
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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