Skip to Main Content
 

Global Search Box

 
 
 
 

Files

File List


19502.pdf (3.69 MB)

ETD Abstract Container

Abstract Header

The Influence of Climate and Topography in Modeling Distributions for Species with Restricted Ranges: A Case Study Using the Hawaiian Endemic Plant Genus, Schiedea (Caryophyllaceae)

Yadav, Sunita
http://orcid.org/0000-0002-4740-602X
http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447690823

Abstract Details

2015, PhD, University of Cincinnati, Arts and Sciences: Biological Sciences.
Dynamic environments affect species distributions and as a consequence also influence intraspecific genetic variation in both space and time. Many factors determine why a species persists in a particular location, some related to environmental tolerances or colonization history, while others are attributable to biological competition or dispersal limitations, such as that occurring on oceanic island systems. Islands are hotspots of endemism where the potential impacts of habitat modification on biodiversity could be substantial. Therefore, the goal of this dissertation was to investigate the influence of the abiotic environment on species geographic distribution patterns and on breeding system distribution within an island genus, in addition to examining genetic diversity within a broadly distributed endemic species. Field collected species presence and absence data for Schiedea globosa were used with climate and topographic predictors to evaluate four different species distribution models (SDM): GLM, GAM, Maxent, and Random Forests. The most accurate model was then used to predict the impact of average shoreline change on suitable habitat at two future time periods. Additionally, I investigated the intraspecific genetic diversity and fine-scale spatial genetic structure for the same species using 11 microsatellite markers from seven populations on the Hawaiian Islands of Maui and O’ahu. Finally, a community-level SDM approach examined the association of abiotic variables with different breeding systems within Schiedea. Abiotic niches for five breeding groups (hermaphroditic-outcrossing, hermaphroditic-selfing, gynodioecy, subdioecy, and dioecy) composed of 33 Schiedea taxa are described from models developed with georeferenced species occurrence records and environmental data. At a species level, the most accurate SDM describing S. globosa habitat was the Random Forests model that included six predictors with topographic predictors as the top three predictors. Two of the seven populations are predicted to be critically affected by loss of suitable habitat due to shoreline change, with higher predicted losses on Maui than on O’ahu. Results from genetic analyses indicate that diversity is relatively high in S. globosa (Ho=0.256 and NA=5.6). Strong spatial structure was detected between islands, and within populations with a larger geographical area and demographic size. Estimated average shoreline change in the next 100 years, assuming no change in genetic diversity, was predicted to affect two of the seven populations with loss of one unique allele. At the genus level, there were large differences among breeding system SDMs in their responses to environmental predictors and little to moderate amounts of niche overlap among breeding systems. The largest niche overlap was between the gynodioecious and dioecious groups with the lowest between the hermaphroditic-selfing and subdioecious groups. This research on a narrowly distributed endemic species provides useful information on variable and model selection to make inferences on the sensitivity of such species to future habitat change. The combination of genetic and spatial analytical tools utilized here provides useful predictions to forecast biodiversity consequences while taking into account projected habitat change. Results from pairwise niche comparisons among breeding systems within the entire genus highlight abiotic factors that are associated with the distribution and diversification of breeding systems within Schiedea.
Theresa Culley, Ph.D. (Committee Chair)
E. Emiel van Loon, Ph.D. (Committee Member)
Ann K. Sakai, Ph.D. (Committee Member)
Hongxing Liu, Ph.D. (Committee Member)
Eric Maurer, Ph.D. (Committee Member)
Steven Rogstad, Ph.D. (Committee Member)
168 p.
Ecology
distribution; Model; Hawaii; Island; genetics; niche

Recommended Citations

Citations

  • Yadav, S. (2015). The Influence of Climate and Topography in Modeling Distributions for Species with Restricted Ranges: A Case Study Using the Hawaiian Endemic Plant Genus, Schiedea (Caryophyllaceae) [Doctoral dissertation, University of Cincinnati]. OhioLINK Electronic Theses and Dissertations Center. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447690823

    APA Style (7th edition)

  • Yadav, Sunita. The Influence of Climate and Topography in Modeling Distributions for Species with Restricted Ranges: A Case Study Using the Hawaiian Endemic Plant Genus, Schiedea (Caryophyllaceae). 2015. University of Cincinnati, Doctoral dissertation. OhioLINK Electronic Theses and Dissertations Center, http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447690823.

    MLA Style (8th edition)

  • Yadav, Sunita. "The Influence of Climate and Topography in Modeling Distributions for Species with Restricted Ranges: A Case Study Using the Hawaiian Endemic Plant Genus, Schiedea (Caryophyllaceae)." Doctoral dissertation, University of Cincinnati, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1447690823

    Chicago Manual of Style (17th edition)

ucin1447690823
199
© 2015, some rights reserved.Creative Commons License The Influence of Climate and Topography in Modeling Distributions for Species with Restricted Ranges: A Case Study Using the Hawaiian Endemic Plant Genus, Schiedea (Caryophyllaceae) by Sunita Yadav is licensed under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License. Based on a work at etd.ohiolink.edu.
This open access ETD is published by University of Cincinnati and OhioLINK.