Article
Disentangling Fragmentation Effects on Herbivory in Understory Plants of Longleaf Pine Savanna
Ecology
(2016)
Abstract
Habitat fragmentation affects species and their interactions through intertwined
mechanisms that include changes to fragment area, shape, connectivity and distance to edge.
Disentangling these pathways is a fundamental challenge of landscape ecology and will help
identify ecological processes important for management of rare species or restoration of frag-
mented habitats. In a landscape experiment that manipulated connectivity, fragment shape, and
distance to edge while holding fragment area constant, we examined how fragmentation impacts
herbivory and growth of nine plant species in longleaf pine savanna. Probability of herbivory in
open habitat was strongly dependent on proximity to forest edge for every species, increasing
with distance to edge in six species (primarily grasses and annual forbs) and decreasing in three
species (perennial forbs and a shrub). In the two species of perennial forbs, these edge effects
were dependent on fragment shape; herbivory strongly decreased with distance to edge in frag-
ments of two shapes, but not in a third shape. For most species, however, probability of herbi-
vory was unrelated to connectivity or fragment shape. Growth was generally determined more
strongly by leaf herbivory than by distance to edge, fragment shape, or connectivity. Taken
together, these results demonstrate consistently strong edge effects on herbivory, one of the
most important biotic factors determining plant growth and demography. Our results contrast
with the generally inconsistent results of observational studies, likely because our experimental
approach enabled us to tease apart landscape processes that are typically confounded.
Keywords
- connectivity,
- corridors,
- edge effects,
- fragment shape,
- habitat fragmentation,
- herbivory
Disciplines
Publication Date
September, 2016
DOI
10.1002/ecy.1466
Citation Information
D. J. Levey, T. Trevor Caughlin, Lars A. Brudvig, Nick M. Haddad, et al.. "Disentangling Fragmentation Effects on Herbivory in Understory Plants of Longleaf Pine Savanna" Ecology Vol. 97 Iss. 9 (2016) p. 2248 - 2258 Available at: http://works.bepress.com/timothy-caughlin/12/