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Drought Tolerance In Native And Invasive Populations Of The Centaurea Jacea Hybrid Complex, Zoe Portlas

Graduate College Dissertations and Theses

Introduced plants face many ecological and evolutionary challenges when establishing in a new range, such as strong abiotic stressors and potentially novel selective environments. One such abiotic stress is water availability, which is a strong selective force shaping physiological and phenological traits that enable plants to tolerate or avoid drought stress. Despite the challenges of establishing in a new range, thousands of species have become invasive in recent centuries. Two hypotheses that may explain how a species is able to withstand stress in its introduced range are preadaptation, which posits that species are adapted to similar environments in their native …

Evolution Of Drought And Low Temperature Responses In Temperate Pooideae Grasses: Timings, Determinants, And Intersections, Aayudh Das

Graduate College Dissertations and Theses

Anthropogenically-mediated rises in atmospheric CO2 and global average temperatures is leading to increasingly severe drought and extreme weather events, the latter including unseasonal bouts of low and high temperatures. In order for plant breeders and conservation biologists to predict future responses to global warming, they must understand the ecological and evolutionary processes that shaped plant tolerance to stressful environments in the past. This is particularly true for grasses (Poaceae) that dominate approximately one-third of the Earth's vegetative cover, live in some of the world's harshest terrestrial environments, and are tremendously important, both ecologically and economically. One of the largest subfamily …

Exploring Mycorrhizae In Riparian Restoration To Enhance Phosphorus Mitigation And Pollinator Habitat On Unceded Territory, Jessica Ann Rubin

Graduate College Dissertations and Theses

When land degradation imperils freshwater quality, land managers can restore ecosystem functions. The premise of three published/accepted thesis chapters is that mycorrhizae can enhance water quality function of riparian buffers and pollinator habitat through diverse, native polyculture associations.

Where water quality is threatened through excess phosphorus (P) loads from agriculture, riparian buffers are considered Best Management Practices (BMPs). They intercept agricultural nutrients before reaching waterways. However, their seasonal cycles, saturation capacity, and often degraded conditions limit their ability to protect water quality. In particular, riparian buffers can transition from sinks to sources of P when agricultural practices chronically contribute P, …