As climatic conditions change, species will be forced to move or adapt to avoid extinction. Exacerbated by ongoing climate change, California recently experienced an exceptional drought from 2012-2014. To investigate whether an adaptive response occurred to this event, I conducted a “resurrection” study of the cutleaf monkeyflower (Mimulus laciniatus), an annual plant, by comparing trait responses of ancestral seed collections ("pre-drought") with contemporary descendant collections ("drought"). Plants were grown under common conditions to test whether this geographically-restricted species has capacity to respond to climate stress across its species range. My research examined if traits shifted in predicted ways in response to recent, severe drought and if the responses varied by climate region. I found days to emergence (i.e. seedling emergence from soil) in the drought generation were significantly fewer as compared to the pre-drought generation. Additionally, trait variation in days to emergence was reduced in the drought generation, which may suggest that a selective event occurred. Days to first flower differed significantly by region and increased with elevation, suggesting climate adaptation across the species range. The drought generation plants were larger and had greater reproduction as compared to the pre-drought generation, which may be attributed to earlier germination of these populations in the greenhouse. My results demonstrate that rapid shifts in trait means are possible within populations, including peripheral populations of a plant species with a relatively restricted range, consistent with climate adaptation. This study highlights the need for better understanding of rapid adaptation as a means for plant communities to withstand climate change.

Nearly 90% of California’s vernal pool habitat has been destroyed by human activity in the past 100 years. The University of California, Merced manages one of the largest actively protected vernal pool habitats in the state, the UC Merced Vernal Pools and Grassland Reserve (MVPGR), aimed at conserving rare native species and landscapes through research, teaching, and outreach. Because the reserve was only recently established, little is known about the interannual patterns of vernal pool plants occupying the region. Consequently, the phenological and demographic responses of the native species inhabiting the MVPGR to reduced precipitation, biological invasions, and cattle grazing has not been quantified. The goal of this dissertation is to investigate the composition, flowering time, and invasion intensity of vernal pool plant communities across multiple climate years. Chapter 1 focuses on two wildflowers native to California, Limnanthes douglassi ssp. rosea (meadowfoam) and Trifolium variegatum (whitetip clover), and quantifies each species’ phenological response to variable precipitation and temperature across 7 years. Additionally, population size of both focal species in response to competition and eutrophication were assessed. I found that both meadowfoam and whitetip clover flower earlier in response to lower precipitation. Chapter 2 focuses on plant community responses to abiotic and biotic dynamics across zones within pools, which are established by soil texture and flooding gradients. Chapter 2 expands upon Chapter 1 by characterizing the community composition, invasion intensity, and interannual flowering trends of 42 plant species across three zones: pool bottom, edge and upland. I found a distinct plant community occupying each zone, and each zone responded uniquely to invasion and winter precipitation. The pool bottom plant community flowered earlier in response to lower winter precipitation, whereas native species in the upland plant community were negatively associated with non-native species richness. No correlations were found between precipitation and the floral phenology of upland species, and neither was there a correlation between non-native species richness and native biodiversity patterns in the pool bottom. The findings elucidate the sensitivities and ramifications of climate change, invasion, and eutrophication amongst ‘zones of vegetation’ on the UCMGVPR. Conserving the native species also requires community participation in the management and legislative process, and ideally the scientific process. Chapter 3 examines several recruitment and retention methods for a community science project involving UC Merced undergraduates and provides guidance on how to achieve a long lasting and high engagement project. I found that in-person presentations achieved a recruitment rate than email flyers. In addition, giving volunteers the freedom to decide the time and date they volunteer and providing periodic updates in the form of a newsletter can improve retention rate of volunteers at different stages.

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Aim To highlight the importance of combining the geographies of sociocultural

adaptation and biodiversity risk for creating global change conservation strategies.

Location Global.

Methods:  We review global conservation adaptation strategies and the geographies that influence biological risk, as well as sociocultural capacity to set priorities for a conservation response. We then describe relationships among these geographies and discuss criteria for prioritizing areas that will have the greatest potential for effective adaptive action.

Results: Strategic conservation requires integrating biological geographies with physical and cultural geographies to maximize potential success with limited resources.

Main conclusions: Biogeography is important for strategic conservation, but it is not the only geography that matters. There is a physical geography of global change providing a complex backdrop against which biodiversity is responsive. Additionally, there is a human geography that drives the degree of threat through variations in anthropogenic disturbance of natural systems and also drives variation in potential mitigation through sociocultural capacity for conservation action. Conservation biogeography typically considers the physical geography of change and the biogeography of threat; it must expand to consider the sociocultural geography of intervention, negative and positive, if it is to be effective. Consideration of these varying geographies also drives different choices for how to implement conservation strategies.