Seed predation along an elevational gradient in the Tropical Andes, Peru

The study of plant species response to climate change is primarily a study of plant distributions along environmental gradients, on which biotic interactions exert a large impact. Post-dispersal seed predation is a plant animal interaction that affects the population dynamics, community structure, and diversity of plant species through time and space. This thesis presents a comparative seed predation study of 24 species of tropical trees across a 2.5 km elevation gradient in the Peruvian Andes. The following questions were asked (1) does seed predation vary across the elevation gradient? (2) do predation rates vary among species and are those rates predictable from species traits such as seed size or current elevational range? And (3), what may be the underlying cause of variation in seed predation rates in terms of ecosystem productivity and associated animal communities? Species exhibited marked variation in total seed predation and in seed predation across the elevation gradient. For all species combined there was a significant decrease in seed predation at high elevations, resulting in an 5.6 increase in effective fecundity for trees at 3450 m. The overall trend in seed predation across elevation potentially arises due to seed predator regulation via top-down forces in the lowlands giving way to bottom-up (productivity) regulation at mid to high elevations.

Grantor dc:publisher

Wake Forest University

Year dc:date.issued

2009

Author dc:creator

• Hillyer, Rachel

• tropical ecology

Language dc:language.iso

en

Handle dc:identifier.uri

http://hdl.handle.net/10339/14674

OAI identifier oai:identifier

oai:wakespace.lib.wfu.edu:10339/14674