Skip to page navigation menu Skip entire header
Brown University
Skip 13 subheader links

Disturbance History and Ecological Change in a Hawaiian Dryland

Description

Abstract:
Dryland ecosystems were considered the most diverse in the Hawaiian archipelago. Today, less than 5% of original dryland habitat remains. Although contemporary wildfires and the historical introduction of nonnative plants and feral mammal populations have fundamentally altered these systems, we do not understand the extent to which these factors have shaped trajectories of primary succession and long-term ecosystem development. Here I investigate how vertical stature and species composition in a sub-alpline Hawaiian dryland ecosystem on the leeward flank of Mauna Loa varies across a volcanic substrate-age gradient. I used measurements from airborne imaging spectroscopy and LiDAR to quantify the biophysical structure and composition of vegetation and found that both vertical stature and species composition changed during primary succession. My results reveal a progressive increase in vertical stature on younger substrates, followed by a collapse on Pleistocene-aged flows. I used biological materials preserved in the stratigraphy of soil-pit profiles to investigate the history of fires and the composition of vegetation during the Holocene. I found that C4 plant contributions of δ13C to SOM increased and persisted during the Holocene Climate Optimum. I also detected a record of fire history over the previous 15,000 years before present. These data suggest that Hawaiian dryland plant communities coexisted and developed with wildfires prior to human arrival. Finally I explore questions about prehistoric avifaunal diversity and the exploitation of these resources in Hawaiian drylands using ancient DNA from faunal bones in cave-shelter middens produce by indigenous Hawaiians. This research revealed a diverse record of prehistoric avifauna that may have been used as resources by people inhabiting Pōhakuloa. I also identified several new records of avian taxa in BBM samples that were not identified by previous archaeological investigations. Taken together, this body of work contributes to understanding of the forces and events that have acted on Hawaiian dryland systems over long time scales. This work can have important implications for understanding ecological processes and for informing adaptive management and restoration practices.
Notes:
Thesis (Ph.D. -- Brown University (2016)

Access Conditions

Rights
In Copyright
Restrictions on Use
Collection is open for research.

Citation

Kinney, Kealohanuiopuna Makela, "Disturbance History and Ecological Change in a Hawaiian Dryland" (2016). Ecological and Evolutionary Biology Theses and Dissertations. Brown Digital Repository. Brown University Library. https://doi.org/10.7301/Z0T43RHV

Relations

Collection: