Anyone familiar with California agriculture knows that the industry regards the state’s stringent regulations as a curse visited upon it by robotic bureaucrats, crackpot environmentalists, and selfish urbanites who don’t know where their own food comes from.
Like all simplistic pictures, this one is wrong in certain respects. A study recently published in the journal Nature Food illustrates why: air quality standards, however irksome, have increased crop productivity in the state’s bountiful San Joaquin Valley.
The study, covering 1980 to 2015, concluded that reductions in pollution over that time resulted in $600 million in increased production annually for perennial crops, including grapes, almonds, nectarines, peaches, strawberries, and walnuts.
“A lot of California farmers may not appreciate that air quality standards have had such a benefit on their ability to grow crops,” says Steven Davis, UCI associate professor of earth system science, a coauthor of the study. “The irony is that by fighting against certain environmental regulations, these folks may be damaging their own earning capacity.”
Ambient ozone, generated by energy production and transportation sectors, can reduce productivity in table grapes up to 22 percent, the study found. In strawberries, the figure is 2 percent; in freestone peaches, 11 percent; in nectarines, 9 percent. Other crops affected were wine grapes, walnuts, and hay.
Although ozone pollution has improved over the last forty years, it hasn’t gone away. “Despite these steady improvements . . . and efforts to raise environmental standards, cut carbon emissions and combat climate change, California’s particulate and ozone pollution remains among the worst in the nation,” the study adds.
“If you look at a map of the state, you’ll see an overlap in areas such as the San Joaquin Valley where many perennial crops are grown and which have high levels of ozone pollution,” said Chaopeng Hong, a UCI postdoctoral scholar in earth system science and lead author of the study.
A 2019 report by the American Lung Association indicated that after Los Angeles, the most ozone-polluted metropolitan areas in the U.S. were Visalia, Bakersfield, and Fresno-Hanford-Madera—all of them in the San Joaquin Valley.
Tropospheric ozone is created when nitrogen oxide, mostly generated by human activity, reacts with organic compounds in sunlight. The ozone burns plant cells through oxidization. This hinders photosynthesis and reduces the amount of energy plants have for producing fruit.
Previous studies had focused on bulk commodities such as wheat, rice, and soybeans. This study focused on perennial crops not only because they have greater long-term susceptibility to pollution, but because they are of high value and are particularly important to California agriculture.
Environmental regulations are irksome to growers, especially because they find it difficult to pass on the increased costs on in the form of higher prices. But there is some consolation in knowing that regulations aren’t always the enemy.