From alarming global warming predictions to the perennially dour drought conditions, the daily news cycle offers no shortage of environmental gloom. Polluting humans are reaping what they sow at an increasing pace, but by now that's barely news at all – especially in the West.

Under the weight of that dismal forecast, I recently met someone who brightened my day.

His name is John Cushman. He is a professor in the Department of Biochemistry, Molecular Biology & Biotechnology at UNR. His scientific research has been varied over a career approaching its fourth decade, but what motivates him holds the potential to improve agriculture efficiency in an arid climate and address two pressing environmental issues: increasing water scarcity and rising levels of atmosphere-warming CO2.

You might say the humble pear cactus (Opuntia, by its scientific name) is the apple of his well-trained eye. Sustainable varieties that Cushman and his colleagues are studying show great promise as a water-saving source of livestock feed. Cushman has filed patents on some of his findings in a long-term endeavor funded by the U.S. Department of Energy (DOE), Western Sustainable Agriculture Research & Education program and the Nevada Agriculture Experiment Station.

"We are focused on the development of alternative crops that are going to do well in the driest state in the United States, and also the fact that 100 percent of all agriculture in the state requires irrigation," Cushman explains from his cramped lab/office on the second floor of the Howard Medical Sciences building. "That means we want to work on plants and crops that use less water. That's what I've been working on all my career."

The subject has held a fascination for the Pennsylvania native since his postdoctoral research at the University of Arizona and further work in Oklahoma. Now in his 26th year at UNR, he considers the university and its location an ideal fit. When it comes to studying plant water efficiency, Nevada provides a field laboratory in every direction.

Widespread use of alfalfa to feed livestock in the West began about the time of the Gold Rush. Although Nevada is well known for its cattle grazing on vast, arid stretches of sagebrush-covered public lands, alfalfa remains a primary source of stockfeed.

But growing it uses a lot of water: up to 8- and 12-acre feet per year.

"But if you grow Opuntia, it's about two — and that's a one-sixth water requirement," the professor explains.

That creates a genuine opportunity. If the pear cactus, a spineless cousin of the prickly pear commonly found in Nevada, can be grown at an agricultural scale, its potential as livestock feed, produce and biofuel is vast. Its fruit and paddle-shaped stems called cladodes are increasingly found in supermarkets.

The plants also produce methane and ethanol, making for the possibility of their multiple use in biofuels in the way corn and soybeans are used today. (Thus the funding support from the DOE.)

"We're pretty limited right now in the expansion of biofuel production," Cushman explains. "It's going up slowly, but if we really want to switch over to biofuels, we need to expand the feedstock. And the only way to do that is to start looking at these arid regions. And Opuntia is really a good choice for that because it requires so much less water. The Western United States is predicted to get about 15 percent drier than it is now, and we're already seeing that with the extended drought episodes that we're experiencing."

But doesn't cactus grow slowly?

"This is the common view. In their natural environment, people look at that and see they're very slow-growing, which is true," Cushman says. "However, we focus on an agricultural setting, and that's very different."

On an annual basis, Cushman and his colleagues have found, the Opuntia produces the same volume of biomass as alfalfa with six times greater water efficiency. With replicated fields planted in 240 varieties of pear cactus in Nevada, California, Arizona, Texas and Florida, researchers are able to gauge which strain is most water-efficient and best suited for the various climates.

Add to that the fact the plant uses a type of photosynthesis that captures planet-warming CO2 from the atmosphere, and you're forgiven for feeling a little hopeful.

"We're really interested in water-saving, but also, can we use this as a carbon sequestration crop?" he asks.

No one is going to see the millions of acres of alfalfa under cultivation in the United States replaced by spineless pear cactus any time soon, but Cushman's work allows us to see what is possible. There is no single solution to combating climate change and long-term drought.

Given the damage being done to the planet and the antiscientific disinformation that pervades the atmosphere, a habitable future remains an underdog in this fight. But funding research of dedicated scientists such as Cushman gives us our best chance to find the essential pieces of our existential puzzle.

John L. Smith is an author and longtime columnist. He was born in Henderson and his family's Nevada roots go back to 1881. His stories have appeared in New Lines, Time, Reader's Digest, Rolling Stone, The Daily Beast, Reuters and Desert Companion, among others.