Posts Tagged: water

Overhead irrigation holds water-saving potential for California farms

In California, 40 percent of agriculture is still irrigated by pouring water onto farmland, a much less efficient practice that drip and overhead irrigation. But those numbers are changing, reported Matt Weiser on Water Deeply. 

Weiser interviewed UC Cooperative Extension cropping systems specialist Jeff Mitchell about the water-saving potential of using overhead irrigation, a system that is popular in other parts of the nation and world, but only used on 2 percent of California farmland. Mitchell was the primary author of a research article in the current issue of California Agriculture journal, which said that water and money can be saved using overhead irrigation in production of wheat, corn, cotton, onion and broccoli.

Mitchell said California researchers are looking more closely at overhead irrigation because they anticipate future constraints on agriculture, including water and labor shortages. Additionally, the system is ideal for combining with conservation agriculture systems, which include the use of cover crops, leaving crop residue on the soil surface and reducing tillage disturbance of the soil. The combination of overhead irrigation and conservation agriculture practices reduces water use, cuts back on dust emissions, increases yield and improves the soil.

Weisner asked how overhead irrigation could be as efficient as drip, when people typically see "water spraying everywhere from these roving sprinklers high off the ground."

Mitchell said farmers use pressure regulators and a variety of nozzles on hoses hanging down from the system to deliver water at precisely the rate and location where it is needed through the season.

"So, they're not spraying water. These are low to the ground, and there are various delivery nozzle practices that can be used," Mitchell said.

UC ANR vice president Glenda Humiston visits the Imperial Valley

Glenda Humiston, the UC Agriculture and Natural Resources vice president who was appointed to her position last summer, toured the Imperial Valley yesterday to become familiar with agricultural and environmental issues in the state's southernmost desert region, reported Edwin Delgado in the Imperial Valley Press.

Humiston visited local farms, the Salton Sea, and UC Desert Research and Extension Center and UC Cooperative Extension in Imperial County. She had discussions with local farmers and industry representatives about renewable energy, drought and water issues, and agricultural production.

"It's great ot have our new vice president here to learn about the programs that we have here and discuss how we can improve them and bring more resources to the area," said Khaled Bali, director of UCCE in Imperial County. "That is basically my objective, bringing more resources to the area and have more collaborative projects."

Andy Horne, a Imperial County executive, said that solar farms have expanded in the county. Projects in place and those approved will cover about 4 percent of Imperial County farmland, a level the county intends to maintain. Humiston told the reporter that she is an advocate for farmland protection because the planet as a whole has a limited surface for cultivating crops.

"As we are dealing with things such as climate change and invasive species and drought, not only protecting those acres so that they are available but keeping them healthy and making sure water is available becomes ever more important," Humiston said.

The debate over dairy products is being milked for all its worth

Since the 1960s, nutrition experts have encouraged Americans to forgo whole milk in favor of skim or low-fat dairy products. Now some scientists are saying the move to low-fat dairy is tied to the country's obesity crisis, according to an article in The Guardian

Robert Lustig, professor of pediatric medicine at UC San Francisco, said he believes drinking whole milk can lead to lower calorie intake overall because it is more filling than low-fat and non-fat alternatives. 

A UC Agriculture and Natural Resources (UC ANR) expert shared a different viewpoint. Lorrene Ritchie, director of the UC ANR Nutrition Policy Institute, said low-fat or skim milk products are still preferable to whole milk because liquid calories are not as filling as equivalent calories from solid food. Nationwide, the goal for most people should be to reduce calorie intake.

"Until we decrease calorie intake on a population level, we are unlikely to see much reversal in the obesity epidemic," Ritchie said.

Before the end of 2015, the federal government is expected to release its revised Dietary Guidelines for Americans. According to the Guardian article, the guidelines are expected to tout vegetables, fruits, whole grains, legumes, nuts, seafood and "low- or non-fat dairy." The guidelines inform the USDA's dietary infographic, which at the moment takes the form of a plate half filled with vegetables and fruit, and the other half with a small portion of protein food and whole grains.

The Nutrition Policy Institute has been advocating for the addition of water on the MyPlate icon to reinforce its position that plain tap water is the best choice for quenching thirst.

Samuel Sandoval Solis shares his passion for water resource management

The cover story in the most recent issue of Visión Magazine details the passion and expertise of UC Agriculture and Natural Resources' water resources scientist Samuel Sandoval Solis, a UC ANR Cooperative Extension specialist based at UC Davis.

Solis was born in Mexico City and began contributing to the family income at the age of 13 as a grocery store bagger. He earned a bachelor's degree in civil engineering at Instituto Politecnico Nacional.

When Solis was hired to help a community of 300 manage its water resources, he was nervous about his abilities, the article said.

"However, like many hardworking Latinos, Samuel put his fear and doubts to the side, and decided to pursue this great opportunity," wrote reporter Vanessa Parra. 

Solis earned a master's degree in hydraulics at Instituto Politecnico Nacional, and a Ph.D. in environmental and water resources engineering at the University of Texas, Austin. His research centered on the Rio Grande, a river shared by Mexico and the U.S. (Mexicans call the river Rio Bravo.)

"I was under friendly fire from people of both nations," Solis said. "Because I was doing my research in the Rio Grande/Bravo while living in Texas, people from the U.S. thought I was a spy and people from Mexico thought that I was a traitor," he said.

The language and culture barriers that Solis once perceived as negative characteristics became valuable assets when he joined the University of California. He is able to communicate with Spanish-speaking farmers on a personal level. 

Solis began his work in California just as it was caught in the grip of the current four-year drought. The dry period, he said, can be viewed as a "tipping point" to change the way the state uses and manages its water. His research focuses on water planning and management.

"We develop methods for finding strategies to better distribute water, ensuring adequate quality and the right timing," Solis said. "We consider the scientific, social, environmental, and economic aspects of basins. Our goal is to improve California's water management through cooperation, shared vision and science-based solutions."

Growing wine grapes without irrigation possible for some, not all

California's ongoing drought is raising the interest of wine grape growers in dryland farming, reported David Pierson in the LA Times. Pierson interviewed Napa Valley growers who are already dry farming their vineyards. While it may be feasible to rely solely on rainfall in the Napa Valley, San Joaquin Valley growers would have a hard time setting a grape crop without irrigation.

"If you don't water in the San Joaquin Valley, you're not getting a yield," Larry Williams, a professor in the Department of Viticulture and Enology at UC Davis and based at Kearney Agricultural Research and Extension Center, told Pierson.

Last month Sacramento Bee columnist Mike Dunne used Williams' study of water use of chardonnay grapes in the Carneros Region to refute the amount of water a Dutch researcher claimed was required to produce a single glass of wine. “In California vineyards and cellars, is 29 gallons of water to produce a single glass of wine a realistic estimate?” Dunne asked Williams, who explained that California grape yields per gallon of water are much higher than in Europe.

“The mean yield of wine grapes in Europe ... is around 1.8 tons per acre using data I've gleaned from research papers,” Williams says. “The mean chardonnay yields across California are 7.4 tons per acre.”

Based on Williams' research, Dunne wrote, “Vines of the dry-farmed portion yielded 4.9 tons per acre, while vines on the irrigated portion produced 6.3 tons per acre. The upshot was that 14.2 gallons of water was needed in the dry-farmed block to produce a typical 4-ounce pour of wine, while 15.3 gallons of water was needed in the irrigated parcel to produce a 4-ounce pour of wine, totals far lower than the figure calculated by the Water Footprint Network.”

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