Thursday, September 09, 2021

The New Dust Bowl

 The seemingly bottomless Ogallala aquifer watered the Texas Panhandle for decades. Now it is drying up.  Groundwater that sustained livelihoods for generations is disappearing, which has created another problem across the southern plains: When there isn’t enough rain or groundwater to germinate crops, soil can blow away — just as it did during the Dust Bowl of the 1930s.

 But the 174,000-square-mile (450,658-square-kilometer) Ogallala — one of the world’s largest — is vital to farmers and ranchers in parts of eight plains states from South Dakota southward. The region produces almost one-third of U.S. commodity crops and livestock protein.

I Texas, along with parts of New Mexico and Oklahoma, water is disappearing more rapidly than elsewhere in the aquifer, also called the High Plains. Less frequent rain linked to climate change means groundwater often is the only option for farmers, forcing tough choices. A 2020 study projects that 40% of irrigated lands in the Central High Plains and 54% of Southern High Plains will be unable to support irrigated agriculture by the end of the century due to a drop in water levels of the Ogallala Aquifer. Federal officials are encouraging farmers in a “Dust Bowl zone” to preserve and restore grasslands to prevent wind erosion as irrigation becomes more difficult.

Some are growing crops that require less water or investing in more efficient irrigation systems. Others also are replacing cash crops with livestock and pastureland. And more are returning land to its literal roots — by planting native grasses that green with the slightest rain and grow dense roots that hold soil in place. While non-native grass dies during droughts, native grass goes dormant and the roots — up to 15 feet (5 meters) deep — hold soil.

The Texas Panhandle almost certainly will continue to be locked into extended periods of drought that have persisted across the Southwest for 20 years, says meteorologist Brad Rippey with the USDA.

“Everybody knows that the water’s going away,” he says.

More than half the currently irrigated land in portions of western Texas, eastern New Mexico and the Oklahoma Panhandle could be lost by the end of the century — with 80% of those losses by 2060, according to a study published last year.

But areas throughout the aquifer also are vulnerable. The central part could lose up to 40% of irrigated area by 2100, with more than half the losses in the next 40 years. The USDA has identified a “Dust Bowl Zone” that covers parts of Colorado, Kansas, New Mexico, Oklahoma and Texas vulnerable to severe wind erosion and where grasslands conservation is a priority.

Already, reestablishing native vegetation in the sandy soil over the Ogallala has proven difficult where irrigation ceased on former Kansas farmland. The same is true on land outside the Ogallala previously irrigated by rivers, including in Colorado’s Arkansas River Valley, where agricultural land dried out before native grasses could be established.

With less rainfall, farmers likely will need to use some remaining groundwater to reestablish native grasses to avoid Dust Bowl conditions, says study co-author Meagan Schipanski, an associate professor of soil and crop sciences at Colorado State University. “In an ideal world, there would be some forethought and incentives available” to help farmers make the transition “before there’s not enough water there,” Schipanski says.

Farmers sometimes plant crops even if they’re likely to fail, because they’re covered by insurance. And cultivating land often is more profitable than taking government payments to preserve or restore grasslands. From 2016 through mid-2021, fewer than 328,000 acres (132,737 hectares) were enrolled in the USDA’s Grasslands Conservation Reserve Program in Dust Bowl Zone counties.

The transition to grasslands and conservation also is hindered by an agricultural banking system that makes it difficult to obtain loans for anything other than conventional farming and equipment, as well as the need to pay off that equipment.

“If you give a producer a choice and flexibility, they’re going to engage in soil health practices,” says USDA’s Ducheneaux, who is advocating for change. “They’re not going to continue to stay stuck in that commodity cycle.” 

But farmers need programs that allow them to earn a living while they make the transition to grasslands over perhaps 15 years, says Kremen, from the Ogallala Water Coordinated Agriculture Project. 

Kremen says. “What’s at stake is the vitality of communities that depend on this water and towns drying up and blowing away.”

Farmers restore native grasslands as groundwater disappears (apnews.com)


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