Bachelor Thesis

The influence of geophysical swell characteristics on present-day vascular plant species richness within oceanic archipelagoes

Charlotte Christina Dietrich (10/2012-11/2012)

Support: Manuel Steinbauer, Carl Beierkuhnlein

Biogeographical theses, theoretically incorporating geological aspects of island shaping have become more common recently, although generalizing models effectively combining defined geological and biogeographical aspects, have yet to be developed. This work is among the first to explain present-day species richness patterns with the help of defined geophysical swell characteristics, thus connecting the fields of geology and biogeography in a novel interdisciplinary approach.
Herein a theoretical framework of interdependent areal, temporal and elevational patterns within oceanic archipelagos is developed. My analysis showed, that islands exhibiting a statistically significant relation between geological age and area, also display a systematic elevation-area pattern, dependent on time. This regularity enabled the subsequent use of defined geophysical swell characteristics (depth, width, buoyancy flux) in explaining present-day vascular plant species richness. This proved to be successful in identifying the width of the melting anomaly as the most influential on present-day species richness.
Analyses are presented for the Azores, Canaries, Cape Verdes, Comoros, Crozet, Galapagos, Hawaii, Juan Fernandez, Madeira, Marquesas, Mascarenes, Samoa and Society.