An irrigation specialist puts down roots in California

Mar 9, 2020

Mallika Nocco is an Assistant Cooperative Extension Specialist in Soil-Plant-Water Relations in the Department of Land, Air and Water Resources at UC Davis.

You are new to UC Davis and UC ANR. Can you tell us a little bit about your background?

I grew up in Minnesota and studied philosophy, cultural studies, and comparative literature at the University of Minnesota-Twin Cities. After graduating, I moved to Wisconsin and worked in pharmaceutical sales for about five years.

I found a passion for gardening and extension through participating in the University of Wisconsin-Madison Master Gardener Program. I fell in love with plants, soil, and ecosystems and decided to go back to school at the University of Wisconsin-Madison to study soil science for my master's degree, and environment and natural resources, with a focus on agrohydrology, for my doctoral degree. I love having a nontraditional liberal arts and business background. I think that it has really helped me with science communication and relating to the farmers and stakeholders who are my partners.

After earning my Ph.D., I was fortunate to receive a 2017 David H. Smith Postdoctoral Conservation Fellowship. The fellowship allowed me to study irrigated agriculture through a wide-angle lens in the Northern Great Lake states of Minnesota, Wisconsin, and Michigan. Throughout the fellowship, I worked with Professor Tracy Twine from the University of Minnesota-Twin Cities, Professor Chris Kucharik from the University of Wisconsin-Madison, Dr. Mike Fienen from the US Geological Service, and Dr. Christel Kern from the US Forestry Service.

Smith Fellows come from many different disciplines, but our passion for policy-relevant science unites us. We receive nontraditional training in media, storytelling, business management, entrepreneurship, and facilitation skills that helps prepare us for leadership roles in academia, government, and non-profits.

Your doctoral and postdoctoral work focused on the relationships between soil, water, plants, and the atmosphere in the Midwest. What kind of research will you be pursuing in California?

One of the things that blows me away about California is the breadth and depth of the irrigation research and all of the brains and hearts working on California water problems. I am pumped to be a part of this community. I thought in depth about how I could best complement adjacent researchers and perhaps bridge some gaps.

In the Midwest, we primarily irrigated specialty crops on very sandy soils using supplemental irrigation. This was because rainfall was usually greater than the rate of water loss from the soil. I worked to quantify irrigated crop water use, groundwater recharge, nitrate leaching, irrigation-climate interactions, and tradeoffs associated with the conversion from forests or rainfed agriculture to irrigated agriculture.

I also worked closely with the Wisconsin Potato and Vegetable Association Groundwater Task Force to co-develop and exchange knowledge via extension. The Midwest's environmental challenges associated with irrigated agriculture relate to groundwater nitrate pollution and surface water depletion, without the additional challenges of groundwater depletion and salinization that exist in California. There are also not over 400 crops to figure out like in California!

I am now building a research and extension program here that leverages my strengths and interdisciplinary background in soil science, environmental biophysics, plant physiology, hydrology, and the sociology of scientific knowledge.

I hope to build on the work I did during my Smith Fellowship. I want to continue doing policy-relevant research that integrates a variety of stakeholders and finds “clunky” solutions to California's wicked water problems. Wicked problems, like many California water issues, are multi-stakeholder dilemmas where no single “optimal” solution will make all stakeholders happy. Instead, there are only “clunky” solutions that involve everyone compromising on goals to make incremental changes.

My new Conservation Irrigation Lab in the department of Land, Air, and Water Resources at UC Davis focuses on three research themes. The first is optimized irrigation, or refining the magnitude and timing of irrigation scheduling to leverage outcomes beyond yield, such as crop quality, nutrition, disease and pest suppression, and water conservation. I am replacing the term deficit irrigation with a new term here—optimized irrigation. Talking with California growers, I found that growers see deficit irrigation as a strategy that results in yield reductions in order to save water. My goal is to find ways to conserve water while increasing production through avenues outside of the ‘water productivity' relationship between yield and applied irrigation.

The second is precision irrigation and monitoring. My research group is developing new tools and algorithms to map crop evapotranspiration and water or salinity stress at very high resolutions. I got into what I call “applied remote sensing” to improve management of soils and water across fields and over time. I noticed that many growers purchased drones and cameras but were unsure how to incorporate them into farm operations or use the data generated. I am looking forward to helping new mappers with photogrammetry and crop water stress mapping as a new UC ANR Drone Camp Instructor this year.

The third is regenerative irrigation, which is my nod to regenerative agriculture. One of my greatest concerns for California's agricultural lands is that irrigation efficiencies are advancing at the expense of soil health. We tend to think of ‘irrigation efficiency' and ‘soil health' in silos. Partly this is because the scientists who study these issues come from very different sub-disciplines, like engineering versus soil biogeochemistry. My Conservation Irrigation Lab will work on strategies to conserve water, while also promoting carbon sequestration and soil health.   

You and your colleague Sam Sandoval recently launched a monthly webinar series called Silver Solutions. Could you tell us a bit more about this?

As I mentioned, I am impressed with the expertise in California Water across UC ANR. Silver Solutions comes from a phrase that Sam often uses that resonated with me when I arrived in California. That is that there is no one “silver bullet” to solve California's water problems, but rather many “silver solutions.” The monthly webinar series is for those of us who study California water to get to know one another's work in detail to foster collaboration and community across the state.

Overall, I am excited about the diversity of ecosystems, growers, scientists, water users, crops, and policies in California. Our challenges are very significant and immediate, but I feel that this urgency is fueling creativity and innovation here. Stakeholders are poised for change and the rest of the world is eager to learn from our innovative approaches. That motivates me on a daily basis.


By Kathryn M Stein
Author - Project Policy Analyst