Insect herbivory is one of the major drivers of seedling mortality in the tropics and influences plant abundances and community composition. Anthropogenic disturbance can alter patterns of insect herbivory with potential consequences on plant communities in restored forests. We planted seedlings of early‐ and later‐stage successional tree species in 13–15‐year‐old restored and remnant tropical forests. We then either excluded insect herbivores or left seedlings exposed to examine how insect herbivory‐affected seedling mortality. Early‐successional seedlings experienced similar decreases in mortality when insect herbivores were excluded from both restored and remnant forest sites, but this effect was smaller and driven by only a few species in restored forests. Later‐successional seedlings experienced a stronger decrease in mortality between open and insect‐excluded treatments in remnant than restored sites. Our results suggest that herbivory‐driven seedling mortality is lower in restored forests, particularly for later‐successional seedlings. Results are encouraging from a restoration perspective because recruitment of later‐successional seedlings is a key component of ecosystem recovery. However, if reductions in seedling mortality continue over the long term, this may affect tree community composition as succession progresses.
This content will become publicly available on November 3, 2024
Restoring vegetation in degraded ecosystems is an increasingly common practice for promoting biodiversity and ecological function, but successful implementation is hampered by an incomplete understanding of the processes that limit restoration success. By synthesizing terrestrial and aquatic studies globally (2594 experimental tests from 610 articles), we reveal substantial herbivore control of vegetation under restoration. Herbivores at restoration sites reduced vegetation abundance more strongly (by 89%, on average) than those at relatively undegraded sites and suppressed, rather than fostered, plant diversity. These effects were particularly pronounced in regions with higher temperatures and lower precipitation. Excluding targeted herbivores temporarily or introducing their predators improved restoration by magnitudes similar to or greater than those achieved by managing plant competition or facilitation. Thus, managing herbivory is a promising strategy for enhancing vegetation restoration efforts.
more » « less- Award ID(s):
- 1832178
- NSF-PAR ID:
- 10483488
- Author(s) / Creator(s):
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Publisher / Repository:
- Science
- Date Published:
- Journal Name:
- Science
- Volume:
- 382
- Issue:
- 6670
- ISSN:
- 0036-8075
- Page Range / eLocation ID:
- 589 to 594
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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