Date of Award

4-2014

Degree Type

Thesis

Degree Name

Master of Science

Department

Biology

Program

Biology

First Advisor/Chairperson

Alan Rebertus

Second Advisor

Roger Strand

Third Advisor

Susy Ziegler

Abstract

Questions. How do spatial and temporal landscape dynamics, including past disturbance, affect the distribution of the seed bank of an early-succession species? Do these factors ultimately influence above-ground subpopulation persistence within a metapopulation framework?

Location. Granite-gneiss outcrops within mixed hardwood-conifer forest in Michigan, USA

Methods. We studied the distribution of the Capnoides sempervirens seed bank on outcrops and within the forest matrix in relation to landscape and physiographic (n = 517). Above-ground plant persistence (n = 144) in relation to landscape and habitat variables was also investigated.

Results. Seeds were found up to 175 m from outcrops, but seed presence generally decreased with increased distance to outcrops. Areas of recent fire had both increased abundance and greater frequency of occurrence of seeds. Seed presence on outcrops shared no relationship with adult plants, but instead corresponded to increased groundcover at sampling locations.

Conclusions. Results indicated seed distribution is not random but reliant upon spatial and temporal predictors. Increased seed presence in relation to adult-plant habitat demonstrated seed bank distribution has some dependence on distance from source populations and primary disperser activity, but the presence of seeds within the greater forest matrix also indicated reliance on landscape, physiographic, or disturbance-related factors. Seed distribution has the potential to influence subpopulation persistence.

Included in

Life Sciences Commons

Share

COinS