Research
Natural climate solutions science and implementation
Natural climate solutions (NCS) include protecting, managing, and restoring natural and working ecosystems in ways that avoid greenhouse gas emissions or increase carbon sequestration. An active area of my work is building the monitoring and research base needed to implement NCS projects, equitably, in ways that meet biodiversity and human needs, in addition to carbon mitigation goals.
Urban forest ecology and societal benefits
Urban forests offer significant ecosystem services, including storm water retention, carbon sequestration, wildlife habitat, and recreation opportunities. My research in urban forests has included understanding how forests operate as part of a social ecological system, such as how we can expand equitable access to the benefits of healthy urban forests and how they affect temperature, as well as ecological studies, such as understanding why natural tree regeneration in urban forested parks is low, including seed limitation and changing forest floor conditions in Seattle's forests,
Climate change and Pacific Northwest forests
Rising temperatures is causing tree ranges and growing conditions to shift. My research includes basic biological questions, such as how climate interacts with competition to affect PNW trees (including observational studies of adult trees and saplings and experimental studies of how seed germination and seedling establishment) as well as applications to forest management, such as climate change refugia.
Phenology and global change
The timing of biological activity such as salmon migration dates or spring leafout in trees, has important implications for organisms' fitness, as well as for human populations. Much of my research has focused on understanding how phenology of diverse species, from salmon and southern resident killer whales to woody plants and orchids, varies in space and time and potential implications of shifts in phenology for conservation. One approach I have used is meta-analysis: synthesizing experiments can be a powerful way better understand climate change-induced shifts in phenology (from quantifying the strength of cues such as winter chilling to understanding how climate change experiments actually alter climate, and what this may mean for these discrepancies and forecasts derived from them).
The role of community science in biodiversity research
Community science ( a more inclusive and accurate term, in my opinion, for what has been frequently previously called "citizen science") has been proposed as a mechanism to gather large volumes of spatio-temporally extensive biodiversity data while simultaneously integrating public outreach into research. There has been a proliferation of community science programs and similar partnerships between scientists and non-scientists; however, the efficacy of these programs in quantifying biodiversity is sometimes questioned. Through a NSF-funded Dimension of Biodiversity Distributed Graduate Seminar (featured in Nature!), we investigated the role of community science in biodiversity-related data and found that in-kind contributions of 1-2 million volunteers can amount to a whopping $2.5 billion per year! I have personally been involved in several community science projects as well, including coordinating New England Wild Flower Society’s Plant Conservation Volunteers, helping to launch the Tree Spotters at the Arnold Arboretum and MeadoWatch at Mount Rainier, and measuring temperature in Tacoma, Washington.
Population dynamics of a rare orchid
Small-whorled pogonia (Isotria medeoloides) grows in moist forests of eastern North America. Like many orchids, individuals of this species will often go dormant for several years before remerging above-ground. The costs, benefits, and environmental triggers of dormancy are unclear, however. I am working with Elizabeth Crone (Tufts University), Andy Royle (USGS), and Bill Brumback (Conservation Director at New England Wild Flower Society) to investigate population dynamics of this threatened orchid, using multi-state models. We study how temporal and spatial variation in the environment affect population dynamics.
Leveraging arboreta to understand tree responses to climate change
I study how traits, phylogenetics, and variation in climatic change affect interspecific differences in climate sensitivity, using annual tree growth at the Arnold Arboretum. The Arboretum provides a unique opportunity to advance climate change research: its unrivaled collection of diverse woody species growing together for over a century enables traits to be studied in a phylogenetic context. Furthermore, many species in the Arboretum’s collections are nonnative and have been exposed to a “novel” climate that may resemble future conditions in their native distributions.
