Back to Sustainability  |  More Profiles
Watch faculty video
Explore More: Read Online Brochure

Louis Santiago

Associate Professor of Physiological Ecology
Assistant Physiological Ecologist
Louis Santiago
Turning Climate Change Around
For centuries, scientists have studied how the environment affects plants. Only recently, with climate change threatening plant communities, have researchers begun to ask how plants affect their environment. The Santiago Lab is uncovering how changes in plant community composition may critically threaten our water resources.

Areas of Expertise

Select Honors and Distinctions

  • U.S. Department of Agriculture E. Kika De La Garza Fellow (2011)
  • National Science Foundation (NSF) Minority Postdoctoral Fellow (2003–06)
  • NSF International Research Fellow (2004)
  • Environmental Protection Agency Science to Achieve Results Fellow (2004)


Q: Describe your research and its applications.
My research examines the relationship between plants and their environment. I would like to understand how plant productivity is determined by the availability of resources such as water, light and nutrients, and how the complex variation of resources along environmental gradients combines to mediate vegetation processes. Understanding how plant processes are structured by environmental resource availability is critical for predicting the responses of plants to environmental change, as well as subsequent effects on natural resource use by humans. In our study of drought resistance of native shrubs in southern California, we have specifically studied how possible changes in plant community composition in response to climate change will affect plant-mediated ecosystem processes such as transpiration, infiltration, and groundwater recharge.

Q: What are some findings from your research on the effects of drought on vegetation in Southern California?
We have been studying the drought resistance of native shrub species at the border between chaparral and Mojave Desert vegetation types, where numerous plant species are suffering mortality after two record-breaking droughts in the last decade. It is relatively straightforward to characterize the physical drought resistance of wood for a particular species and estimate the severity of drought that would cause local mortality. However, we discovered that the least drought resistant species have very deep roots, complicating our predictions of the vulnerability of species to climate change, but also providing hope that these native shrubs can withstand greater droughts than previously thought, and potentially slowing the tempo of change on this landscape

Q: Why is your research important?
Predicting how climate change will affect local plant communities and understanding the implications of these changes on water cycling is critical for mitigating the effects of climate change on our water resources. The data from our comparative study of drought resistance in native California shrubs helps us understand the ecological strategies of these shrub species, which is the first step in predicting how they will responds to a dynamic environment during climate change.

Q: What is sustainable agriculture? How can people become better educated about this topic?
Sustainable agriculture provides food security in the long term without degrading its own resource base — the healthy, natural ecosystems that provide pollinators, healthy soil, biodiversity and a consistent water supply. Educating people on this topic requires an understanding of how our food production systems are tied to natural resources. I find that people have a reasonable understanding of where their food is grown, but not necessarily where their water comes from, or what kinds of water resources are used to produce their food.

Q: In what ways are you and your UCR plant science colleagues communicating basic research to the general public?
We work closely with a broad range of government and community groups, including the Metropolitan water district, the California Avocado Commission, and the Citrus Research Board, to name a few.

Q: How do the goals of sustainability factor into your research?
Plants play a critical role in the environmental cycling of water. Upstream plant- mediated processes such as transpiration, infiltration and groundwater recharge determine water yield downstream. My research addresses how changes in the composition of natural plant communities as a result of climate change will affect the amount of water available for agricultural and societal uses. Numerous locations in the temperate zone are forecasted to become warmer and drier. This has direct impact on the types of crops that can be grown, as well as the level of intensive management that is required to produce food in a changing climate.

Q: What are the big challenges researchers in your field are trying to answer?
The biggest challenge in my field is understanding terrestrial feedback to climate change. As plants respond to climate change, alterations in vegetation-atmosphere exchanges of carbon and water could amplify or dampen the effects of climate change. Determining the likelihood of that impact and the direction of climate forcing are critical for all other effects of climate change on our life support system: clean water, breathable air, and food production.

Q: What is the biggest myth about your research?
The biggest myth about my research is that all plant biologists work on crops. Of course understanding the physiology of our food plants is critical, yet not understanding and conserving the wild plants in natural ecosystems risks losing the pollinators, healthy soil, biodiversity and water supply that support local agriculture.

Q: Where did the inspiration come from for your research?
I started as an undergraduate chemistry major at UC Berkeley. After finishing my third year, I interned in a lab at Clorox Corporation for the summer. During one weekend, I went on a fabulous backpacking trip in Yosemite and when I returned to the sterile corporate chemistry lab on Monday morning, I realized that, although chemical processes were of great interest to me, the context should be environmental rather than commercial. For the rest of the summer I continued going outdoors as much as I could and developed an interest in plants and soil. When summer was over, I switched my major to biology.

Q: What does “Living the Promise” mean to you?
Living the promise means emphasizing the service component of our role as an institution of higher education in California. Much of what we do in our labs is ultimately a service for the public, so for me, part of living the promise is raising awareness for what we do and inviting the public to realize the benefits of our work.

Q: How do your students inspire you?
My students inspire me because they are not weighed down by the dogma of our discipline and therefore are not afraid to ask the challenging questions that the rest of us do not think about so much because we have already been indoctrinated. I love to present the dominant paradigms of our discipline to undergraduates with minimal background to get their gut feeling about our science.

Q: What advice do you have for students graduating in the next five years?
Don’t go into debt.

Q: How are you encouraging undergraduates, especially those from underrepresented groups, to pursue higher education in the sciences?
I encourage undergraduates to pursue higher education through research, especially independent research. I find that when a student has their own project, they really begin to care about all of the details that are related to their question. This level of inquiry and the process of discovery is enough of a motivating factor to pursue scientific careers for many students.

Louis Santiago "Understanding terrestrial feedback on climate is critical for understanding how climate change will affect our life support system: clean water, breathable air and food production."

—Louis Santiago