Sustainable water use in agriculture
Farming food that is healthy for both the environment and people remains a global challenge, especially in arid regions where fresh water is a limited resource. As we found in our paper, although intensive irrigation in farmland can create local temperature depressions that benefit human health, it may also result in unsustainable water use long-term. Balancing these needs is crucial for a more sustainable future. I study the tradeoffs between water use and crop growth using remote sensing data.
Cropland, vegetation cover and evapotranspiration over Davis, California
Solar-induced fluorescence
Solar-induced fluorescence (SIF) is a phenomenon of plants ‘glowing’ as they perform photosynthesis and capture carbon from the atmosphere. Rates of photosynthesis can change instantaneously depending on environmental conditions. Using SIF from satellite and ground-based sensors allows us to understand ecosystem responses to the environment and climate change over time and space.
SIF at a grassland in Point Reyes, CA
SIF at an experimental vineyard in Hopland, CA
Along with a team of other scientists and students, I am deploying a hyperpsectral imager at field sites in California. The imager takes ‘pictures’ of photosynthesis across a landscape, capturing differences in carbon fixation rates between individual plants and even leaves. We’re currently working with the imager to answer questions about drought, soil warming, and plant disease on carbon fixation rates. This work will help us understand terrestrial ecosystem functionality and predict carbon cycling under climate change. Check out our new paper on our SIF fieldwork published in Geophysical Research Letters.
The team at an AmeriFlux site deploying a hyperspectral imager
Ecosystem reliance on groundwater
Groundwater is a critical freshwater resource for both people and ecosystems. Plants in arid and semi-arid systems often rely on groundwater throughout the year and during droughts. Access to water enables plants to continue fixing carbon from the atmosphere even under dry conditions. I use remote sensing and eddy covariance flux tower data to untangle the effects of groundwater depletion on ecosystems that are dependent on groundwater, with the goal of predicting carbon cycling and ecosystem function under future climate change. In our recent paper, we found that groundwater drought can diminish carbon fixation and sequestration rates by almost 20%.
A groundwater-dependent ecosystem in the Sierra Nevada foothills
Human perceptions of climate change
People have developed many ways of studying the environment, and not all of these frameworks have historically been respected by western science. Yet these stewardship practices and observational techniques can provide fresh insights on environmental issues. As a journalist and oral historian, I value diverse perspectives throughout the research process. In Vanuatu, where I undertook paleoclimate and oral history research, I learned how migration, global economies, and kinship networks affect communities’ strategies to remain safe and connected under a changing climate.
In Vanuatu, intensifying cyclones and drought threaten coastal communities