Spatiotemporal Patterns and Drivers of Surface Water Quality and Landscape Change in a Semi-Arid, Southern African Savanna

The savannas of southern Africa are a highly variable and globally-important biome supporting rapidly-expanding human populations, along with one of the greatest concentrations of wildlife on the continent. Savannas occupy a fifth of the earth's land surface, yet despite their ecological and economic significance, understanding of the complex couplings and feedbacks that drive spatiotemporal patterns of change are lacking. In Chapter 1 of my dissertation, I discuss some of the different theoretical frameworks used to understand complex and dynamic changes in savanna structure and composition. In Chapter 2, I evaluate spatial drivers of water quality declines in the Chobe River using spatiotemporal and geostatistical modeling of time series data collected along a transect spanning a mosaic of protected, urban, and developing urban land use. Chapter 3 explores the complex couplings and feedbacks that drive spatiotemporal patterns of land cover (LC) change across the Chobe District, with a particular focus on climate, fire, herbivory, and anthropogenic disturbance. In Chapter 4, I evaluated the utility of Distance sampling methods to: 1) derive seasonal fecal loading estimates in national park and unprotected land; 2) provide a simple, standardized method to estimate riparian fecal loading for use in distributed hydrological water quality models; 3) answer questions about complex drivers and patterns of water quality variability in a semi-arid southern African river system. Together, these findings have important implications to land use planning and water conservation in southern Africa's dryland savanna ecosystems.

Name thesis:degree_name

Ph. D.

Level thesis:degree_level

doctoral

Discipline thesis:degree_discipline

Fisheries and Wildlife Science

Department dc:contributor.department

Fisheries and Wildlife Science

Grantor dc:publisher

Virginia Tech

Year dc:date.issued

2016

Author dc:creator

• Fox, John Tyler

Chair dc:contributor.committeechair

• Alexander, Kathleen A.

Committee members dc:contributor.committeemember

• Prisley, Stephen P.
• Frimpong, Emmanuel A.
• Godrej, Adil N.

• Escherichia coli
• fecal indicator bacteria
• Water quality modeling
• microbial fate
• pollution
• remote sensing
• savanna disturbance ecology
• land cover change
• climate change
• fire frequency
• water-borne pathogens
• wildlife
• erosion
• dryland rivers
• Water quality
• Africa
• ecosystem services

Statement dc:rights

• In Copyright

Licence dc:rights.uri

• http://rightsstatements.org/vocab/InC/1.0/

Dc Identifier Other

vt_gsexam:8489

OAI identifier oai:identifier

oai:vtechworks.lib.vt.edu:10919/81462