Research

Scaling from microhabitat modification to demography

img_7124Microhabitat modification, such as buffering temperatures and locally increasing water availability, is a common mechanism of facilitation in stressful environments. Microhabitat modification can affect diversity and abundance by increasing habitat heterogeneity and altering vital rates. It is not well understood what impact local-scale habitat modification has on plant abundance and distributions, which directly affects our success in applying effective conservation strategies. I study when and at what scale microhabitat modification is facilitative to better predict how plant communities respond to climate variation.

 

Seed dispersal in desert winter annual communities

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Desert winter annual species are expected to have limited dispersal, in part driven by patchy availability of suitable microsites. In a Sonoran Desert community at White Tank Mountain Regional Park, I am experimentally testing these assumptions by comparing seed movement across varied vegetation types.

 

 

Plant invasion, impacts, and management

I am interested in understanding why and when some species are invasive, predicting their impacts, and identifying best management practices. During my master’s, I focused on the invasive grass, Ehrharta erecta, which is currently spreading in California. Ehrharta erecta is drought and shade tolerant, a combination that allows it to invade coastal mixed-evergreen forests. This system has high invasion resistance and only a few sparse native grasses. Visually, the difference between invaded and uninvaded forest is stark; at some locations I have measured 300% greater plant cover compared to uninvaded forests. To test how E. erecta affects native understory plants in this system, I measured native species richness and abundance in invaded and uninvaded forest plots, as well as whether native cover changed with invader density. I also tested the effectiveness of mechanical and chemical management methods at reducing E. erecta abundance, both alone and with post-removal planting of native species.  This research was advised by Ingrid Parker at the University of California, Santa Cruz. Funding was through a NSF Graduate Research Fellowship and UCSC Chancellor’s Fellowship.

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Censusing quaking aspen forests, Gunnison County, CO, summer 2018