Crops in California's Central Valley

California’s Central Valley (Photo credit: Shutterstock)

As two-thirds of the fruits and nuts—and over a third of the vegetables—produced in the United States are grown in California, it’s crucial that the Golden State cultivate healthy soils that are resilient to stresses such as climate change, drought, and groundwater overuse.

Now scientists at Berkeley Lab’s Earth & Environmental Sciences Area (EESA) and Biosciences Area are contributing to the effort by sharing their expertise with the California Department of Food and Agriculture (CDFA)’s Science Advisory Panel, a group comprised of farmers, agriculture professionals, and experts in areas such as water, conservation, and resource management. Last week, EESA scientist Peter Nico hosted the panel at the Lab to brief them on research related to developing healthy soils, sustainable groundwater management strategies, and climate-adaptive agriculture.

“We are parlaying and extending our capabilities to address California’s problems and opportunities,” said Susan Hubbard, Berkeley Lab Associate Lab Director for EESA, to the panel. “Resilient agriculture is an example of an important California topic where there is a huge opportunity for advances through science and technology focused on microbes, soil, plants, water, climate, and their interactions.”

Nico, who leads EESA’s Resilient Energy, Water and Infrastructure program, spoke about the Area’s water resilience research. Developing new strategies to manage water as a sustainable resource is one of EESA’s five Grand Challenges, which outline research goals over the next decade in its Strategic Vision 2025. The topic is also aligned with Berkeley Lab’s Water-Energy Resilience Initiative.

The overuse of groundwater in California was just one outcome of the most recent drought which led to land subsidence of up to 13 inches in some parts of the San Joaquin Valley a few years ago. EESA is developing solutions to help the state make its groundwater supply more reliable.

“We’re testing new water management strategies in demonstration programs, and using those ideas to guide resilient water strategies to make a difference,” Nico said.

Science Advisory Panel members of California's Department of Food and Agriculture gathered with Berkeley Lab scientists group photo

Science Advisory Panel members of California’s Department of Food and Agriculture gathered with Berkeley Lab scientists on July 20, 2017.

One strategy that EESA is studying (in partnership with the Almond Board of California and UC Davis) is groundwater recharge, a process that could help to prevent the depletion of groundwater levels by replenishing aquifers in wet years. During times of heavy rainfall, excess water can be directed from the surface to the subsurface through flooding the fields or orchards of crops that can withstand the higher volume (such as almond trees and wine grapes). As a result, that water is “banked” as groundwater that can be used in times of future need.

But in order to understand the full impact of groundwater recharge, scientists and policymakers must also be aware of which areas of the subsurface are well-suited to banking, and where that water will go once it hits below the surface. Other pieces of information—such as how long it will take for the water to get there, the quality of the water, and how it will affect energy use and land subsidence—are also essential to determine impact. EESA is conducting research to answer these questions using time-lapse geophysical imaging, isotope chemistry, and integrating other advanced datasets into numerical models, Nico said.

Another element key to agriculture and healthy soils that EESA and the Biosciences Area are focusing on is the role of microbes to enhance ecosystem services like water retention and nutrient use efficiency, said Eoin Brodie, EESA senior scientist and deputy director of Berkeley Lab’s Climate and Ecosystem Sciences Division. This work reflects EESA’s Earth’s Microbial Engines Grand Challenge.

“Microbes are essential for the formation of soil organic matter and nutrient cycling in soil,” he said. “They transform plant material, which creates new chemicals that interact with soil minerals to create soil structure that improves water, carbon, and nutrient retention.”

The window to understanding these microorganisms, Brodie continued, is through genetic and advanced sensing technologies. He noted that the supercomputing resources at Berkeley Lab’s National Energy Research Scientific Computing Center, the genetics capabilities at the Joint Genome Institute, and the nanoscience facilities of the Molecular Foundry are key tools to accomplish this research.

Moving on to another of EESA’s Grand Challenge research goals, scientist Trevor Keenan gave the panel an overview of the Area’s work in predicting the trajectory of the carbon sink. The carbon sink is a term used to describe the carbon that is locked up in terrestrial soil and vegetation—therefore out of the atmosphere where it can contribute to climate change in the form of carbon dioxide.

“Currently, the U.S. land sink is considered to be relatively constant, but we don’t have the science to confidently say how it will change in the future,” said Keenan, who studies how plants and the climate affect each other and how that impacts carbon in healthy soils. “This uncertainty makes it difficult to effectively plan targets and strategies for carbon emissions reduction, as we do not know if the land will be healthy and store more carbon, or degrade and release carbon to the atmosphere.”

Peter Nico gives members of CFDA's Science Advisory Panel an introduction to Berkeley Lab's Advanced Light Source.

Peter Nico gives members of CFDA’s Science Advisory Panel an introduction to Berkeley Lab’s Advanced Light Source.

Berkeley Lab is well-positioned to tackle the challenge of being able to predict how much carbon will be deposited into a land sink, Keenan said, because it possesses technology at a range of scales from large data observation networks such as the AmeriFlux network to remote sensing systems in the Arctic and the Tropics that harness drone technology to measure plant properties.

Romy Chakraborty, EESA’s Ecology Department head, briefed the panel on the Area’s work in the Lab’s Urban Agriculture initiative. The effort aims to reduce the ecological footprint of conventional agriculture and determine how to optimize the efficiency and sustainability of growing food with minimal impacts on environmental resources. It also aims to improve food distribution to low-income communities that lack easy access to fresh fruits and vegetables.

“Technical innovation is needed to reach our goals in this area,” she said. “We have a vision to develop novel smart indoor farming units and explore the integration of recent advances of greenhouse technology capabilities, as well as how to achieve sustainable production at scale.”

Within this theme of technology innovation, two of the Lab’s Biosciences Area researchers from the Joint BioEnergy Institute spoke about their work. Graduate student William Moore discussed how studying Medicago truncatula (a wild relative of alfalfa) can provide insight in how to enhance plant-microbe interactions for improved plant yields, while postdoctoral researcher Yan Liang talked about a method that increased the efficiency of genome editing tool CRISPR in plants.

And to wrap up the session, two UC Global Food Initiative fellows presented their research about climate and agriculture in California. Alison Marklein detailed how rising temperatures are projected to affect the state’s growing season for vegetable crops (as well as where those crops can be grown), and Kripa Jagannathan spoke about working with farmers to improve the usability of climate models for their decisionmaking—as well as the need for a framework that helps them access the right data for their specific needs.

In her concluding remarks, Hubbard expressed interest in continuing the dialogue.

“To realize the impact we’d like to have on California agriculture, we look forward to working with you to bring together our scientists with California’s farmers and agricultural technologists,” she told the panel. “We believe these interactions are important for advancing Berkeley Lab’s vision of ‘Bringing Science Solutions to the World.’”