Salt is essential for life, but too much of it can be a problem. That’s true for the human body, but also in nature. Farmers along the Rio Grande in South Texas have had a particularly difficult time keeping excess salinity in river water from ruining their crops.
“Agriculture in the region depends very much on the freshwater supplies from the river,” said Girisha Ganjegunte, professor in the Department of Soil and Crop Sciences at the Texas A&M AgriLife Research Center at El Paso.
Ganjegunte tells Texas Standard that water doesn’t start out with too much salinity, when it begins as snowmelt traveling down from mountains. But debris and chemical runoff from large metropolitan areas and agriculture outfits along the way increase its salinity. That often leaves communities downstream with saltier water.
Salinity can damage infrastructure in urban areas. Ganjegunte cites a study that estimated it causes about $10 million in damage every year.
It’s also bad for agriculture. For farmers to keep their businesses running, Ganjegunte says they’ll have to adapt with new, more salt-tolerant crops. That won’t be an easy adjustment.
“A lot of the agriculture areas have 40-, 50-years-old tree crops such as pecans, and it’s not easy to replace those,” he said. “Usually the option is to go for a salt-tolerant rooting stock.”
Quinoa is one potential option, he says. Quinoa is actually the seeds of a plant in the amaranth family. Ganjegunte’s research group is looking into ways farmers could phase out crops like pecans for this salt-tolerant plant, instead.
“Quinoa is a proteinaceous grain that is highly salt-tolerant and it can produce revenues similar to what growers are getting from cash crops like pecans,” he said.