Population and community responses to anthropogenic environmental changes

Humans are dramatically altering the planet. I use classic ecological theory, original conceptual models, and a novel analytical tool (Rank Occupancy-Abundance Profiles; ROAPs) to explore the effects anthropogenic changes have on plant communities and bird populations. Chapter one investigates the influence of nutrient deposition on native prairie grass communities. I show that soil phosphorus levels alter plant diversity by changing the degree to which mycorrhizae benefit plant species. Chapter two investigates plant extinctions in a fragmented landscape. Extinction rates of early-successional plant species on large versus small habitat patches vary according to species' life history traits. In Chapter three I quantify declines in North American bird species over the past 30 years. Nearly 20% of the 209 birds sampled are declining significantly; local densities tend to decline prior to occupancy. Results from this dissertation confirm that humans are dramatically altering the relative abundance of species--at local, landscape, and continental scales.

Grantor dc:publisher

University of Kansas

Year dc:date.issued

2009

Author dc:creator

• Collins, Cathy Diane

Advisor dc:contributor.advisor

• Foster, Bryan L

• Biology
• Ecology
• Extinction
• Global change
• Habitat fragmentation
• Mycorrhizal fungi
• Prairie
• Roap

Statement dc:rights

• This item is protected by copyright and unless otherwise specified the copyright of this thesis/dissertation is held by the author.

Language dc:language.iso

EN

Dc Identifier Other

http://dissertations.umi.com/ku:10226

OAI identifier oai:identifier

oai:kuscholarworks.ku.edu:1808/6304