- Author: Mike Hsu
Study at Desert Research and Extension Center highlights agriculture's sustainability role
Under the blistering sun of Southern California's Imperial Valley, it's not surprising that subsurface drip irrigation is more effective and efficient than furrow (or flood) irrigation, a practice in which up to 50% of water is lost to evaporation.
But a recent study also concludes that drip irrigation can dramatically reduce greenhouse gas emissions from soil – which contribute to climate change and unhealthy air quality in the region – without sacrificing yields of forage crops alfalfa and sudangrass.
“It was really exciting to see,” said lead author Holly Andrews, a National Science Foundation postdoctoral fellow at the University of Arizona. “The crop yield was at least maintained and in some cases increased, but the water use and gaseous emissions were especially decreased under drip irrigation.”
Desert REC crucial to collecting data
Andrews and her colleagues gathered data from field studies at University of California Agriculture and Natural Resources' Desert Research and Extension Center, a crucial hub of desert agriculture research for more than 100 years. Studies in that context are increasingly important, as much of California and the Southwest becomes hotter and drier.
“We already have this history of looking at drip irrigation at this site, so our study was trying to build on that,” said Andrews, who lauded Desert REC's facilities and staff.
In their study published in Agriculture, Ecosystems & Environment, researchers found that – in comparison to furrow irrigation – drip irrigation in alfalfa slashed per-yield soil carbon dioxide emissions by 59%, nitrous oxide by 38% and nitric oxide by 20%.
Nitrous oxide is a greenhouse gas with nearly 300 times more warming potential as carbon dioxide, and nitric oxide is a precursor to ozone and major contributor to air pollution.
While drip irrigation only decreased water demand 1% in alfalfa, the practice led to a substantial 49% decrease in irrigation for sudangrass. For more fertilizer-intensive sudangrass, drip irrigation also reduced soil emissions of nitrous oxide by 59% and nitric oxide by 49% – the result of drip irrigation making those fertilizers more efficient.
Water management can help mitigate climate change
Studying alfalfa and sudangrass – forage crops with very different fertilizer requirements – was a strategic choice by the researchers. They are number one and number three on the list of most widely grown crops by acreage in the Imperial Valley (Bermudagrass, another forage crop, is number two).
With so much land dedicated to producing these crops, the adoption of drip irrigation at scale could deliver significant benefits to residents' health and quality of life.
“The thought that saving water can increase yields while lowering the emission of trace gases that affect regional air quality and Earth's climate is quite encouraging,” said Pete Homyak, an assistant professor of environmental sciences at UC Riverside who contributed to the study. “This is especially true for the Imperial Valley, an arid region where water is a limited resource and where residents are exposed to bad air quality.”
Homyak, who is affiliated with UC ANR through UC Riverside's Agricultural Experiment Station, said that this study illustrates how changes in water management can substantially mitigate agricultural impacts on the environment.
The study findings should encourage growers to replace furrow irrigation systems with drip irrigation infrastructure – especially in combination with financial incentives from the state, such as cap-and-trade and carbon credit programs, that can help defray high installation costs.
“It really is worthwhile if you're thinking sustainability and environmental activism in how agriculture can actually support climate change mitigation,” Andrews explained. “These practices might be a way that we can start to change that picture a little bit – and make agriculture more sustainable by tailoring irrigation management to local climate conditions.”
In addition to Andrews and Homyak, the other study authors are Patty Oikawa, California State University, East Bay; Jun Wang, University of Iowa; and Darrel Jenerette, UC Riverside.
/h3>/h3>/h2>- Author: Wendy Powers
The view of the snow pack from my garage window has improved somewhat over the weekend, in part due to snow fall and in part due to less fog. It is great to see snowfall at the lower elevations and rain across many areas of the state. I have become a big fan of rain, but not to the extent that I welcome sandhill cranes take up residence in my back acreage again this year. Let's all hope for a slow, soaking rain. The wind is a whole different story. Mark Bell was able to sneak away to the snow this past weekend. The photo he so eagerly shared with me is beautiful. I suspect he might be preparing for the next photo competition, vying for Dustin's title.
Neither cooler, nor warmer, temperatures seem to slow this coronavirus. I came across a cool tool for estimating separation distances for estimating aerosol movement and infection risk. Perhaps the tool will require modification as the prominent variant changes. Also released this week, by CDC, are tools to support vaccine education. The toolkit serves as a starting place to tailor materials to specific audience needs and concerns.
The UC ANR team in Imperial County (UCCE plus the Desert REC) was recently recognized for their contributions to the region. In particular, the new hires were welcomed and introduced to the local community. Congratulations to Oli, Jairo, and their teams!
While the wind has made some Zoom calls a challenge, the meetings continue. NIFA held a day of listening sessions to gather stakeholder input on priorities in animal agriculture. APLU hosted a webinar to talk about broadband's role in rural economic development. Other Zoom discussions have focused on potential partnerships and new funding in the Governor's proposed budget. Yet to occur this week is a meeting of the Vice President's Council where we will cover topics such as funding strategies, supporting volunteers, expanding DEI efforts, and navigating policies. Friday winds down with action steps to move the REC Strategic Framework forward.
I see we have a new feature in Interfolio that notifies me when academics have submitted their annual evaluation materials or dossiers for supervisor review. Nice work to all who have been able to submit in advance of the February 1 deadline! I hope those individuals get to enjoy this weekend. I know everyone else is working hard to put on the finishing touches. Good luck on your submissions. I hope the power stays on for you!
- Author: Brooke Latack
Participants representing Imperial County cattle feedlots came together on April 22nd to discuss food safety at the Livestock Food Safety Workshop held at UC DREC. Organized by UCANR advisors and specialists, invited speakers presented current management practices and research related to food safety with respect to livestock and wildlife. Topics covering packing plant food safety, mitigation of pathogen shedding at the feedlot, and past food safety research initiated a productive discussion amongst participants and speakers to identify key areas of concern and potential for future research. The successful workshop set groundwork for future discussions related to this critical issue.
For further information, please contact:
Brooke Latack
University of California Cooperative Extension (UCCE)
Livestock Advisor (Imperial, Riverside & San Bernardino Counties)
1050 E Holton Rd
Holtville, CA 92250
Office: (442) 265-7712
![Paula Rivadeneira, U of A Food Safety and Wildlife Specialist, presents on past research on pathogen movement in the low desert. Picture by Jairo Diaz Paula Rivadeneira, U of A Food Safety and Wildlife Specialist, presents on past research on pathogen movement in the low desert. Picture by Jairo Diaz](/blogs/blogcore/blogfiles/59972.jpg)
![Rob Atwill, director of UC Vet Med Extension and the UC Davis Western Institute for Food Safety and Security, discusses produce food safety. Picture by Jairo Diaz Rob Atwill, director of UC Vet Med Extension and the UC Davis Western Institute for Food Safety and Security, discusses produce food safety. Picture by Jairo Diaz](/blogs/blogcore/blogfiles/59973.jpg)
- Author: Wendy Powers
Welcome to Beatriz Nobua-Behrmann who starts this week as an Urban Forestry and Natural Resources Advisor, based at the South Coast REC, with programmatic responsibilities in Orange and Los Angeles Counties. Last week, Ryan Tompkins started as the Forestry and Natural Resources Advisor, based in Quincy, with programmatic responsibilities in Plumas, Sierra and Lassen Counties. IT is great to see our forestry capacity building.
I looked at the academic footprint numbers this weekend. It's possible we are down in numbers, but before I share the graph, I want to confirm how counting occurs for some positions. I know we are all very interested in our numbers and growing that footprint; it came up as a question during the Town Hall last week. We have a few CE Advisor and 4 CE Specialist positions yet to fill from the 2016 position call process. Plus we will backfill a Table Grapes Advisor position, based out of Kern County, as a result of a partnership with the California Table Grapes Commission. We should be moving forward with other hirings soon, too.
Also over the weekend, I had dinner with friends. We had teff as part of the meal. Did you know that UC ANR researches teff? Both the Desert REC and the Blythe area have research underway. My friend was quite interested in the study for her work. I think there may be some opportunity to work together on things; we'll see. I was interested to learn that my friends knew about Elkus Ranch and that their kids had been in 4-H! While that may not be surprising to many, it caught me off guard because they live right in the Mission District of San Francisco.
Tomorrow I head to Salinas to meet with the California Leafy Greens Research Program committee. I've met with the group a few times; every 6 or 8 months. Tuesday a dozen of us are at the State Capitol meeting with assembly persons and state senators to talk about the work of UC ANR in their districts. Then Wednesday I am at UC Merced for a tour of the campus and discussions about our partnerships with the university. Although I am home every night this week, it is shaping up to be a bit of car time. Keeping up on emails may prove to be all I can manage. The remaining 51 dossiers will still be there next week.
- Author: Wendy Powers