Table 2. Summary of results obtained by investigations assessing edge effects in tropical montane and south temperate rainforests, two forest types that have been almost entirely neglected by previous research (Harper et al. 2005, Ries et al. 2004). Results presented of measurements of ecological processes, patterns, and microclimate at the forest edge (zero meters) compared with the forest interior, showing higher or lower values of the response variable at the edge, or no difference. Modulators are factors that conditioned the observed response. “Hard” and “soft” edges refer to high- and low-contrast edges, respectively (see text). (Adapted from López-Barrera et al. 2007a).


Response variable Region Modulators Higher Lower No difference
Dynamic processes
Seed rain Chiloé Only fleshy-fruited species X
Chiloé Landscape type   X  
Avian nest predation Chiloé X
Chiloé X
Seed germination Chiapas Species identity X
Seed removal and/or predation Chiapas Only non-masting years X
Veracruz X
Chiloé Species identity, season, and canopy opening X
Seedling herbivory Chiloé X
Chiapas Edge specific: only in hard edges X
Veracruz Season specific: only in the soft edge during the dry season X
Seedling performance (survival and growth) Chiloé X
Chiloé X
Veracruz X
Tree growth rate Species dependent X
Ecological flows
Fog interception and tree regeneration Fray Jorge Fog influx direction X
Seed movement from edge into the exterior Chiapas Edge specific: only in soft edges X
Patterns
Woody species richness/diversity Chiapas X
Veracruz X
Epiphyte cover and species richness Chiloé X
Bryophyte species richness Chiloé X
Avian species richness Chiloé X
Diversity and abundance of native small mammals Chiapas Edge specific: only in soft edges X
Veracruz Only in fragments with soft edges X
Overall tree seedling Chiloé Species identity and shade tolerance X
and sapling density Chiapas X
Veracruz X
Microclimate
Soil moisture Semiarid Chile Fog influx direction X
Veracruz X
Chiapas X
Light Chiapas Edge specific: only in hard edges. X
Air temperature Veracruz X