Hot Stuff, Spring 1996
The following "Hot Stuff" articles appeared in the Spring 1996 issue of New Mexico Resources:
Understanding the Earth's Surface
Curtis Monger's tools are simple--a trowel, some common plastic bags, a sturdy straw hat, and plenty of drinking water. But this NMSU soil scientist's work has implications for understanding one-third of the world's surface, which is covered by desert.
Monger, a researcher with NMSU's Agricultural Experiment Station, studies desertification at sites in the Chihuahuan Desert in both the United States and Mexico.
"Desertification refers to the decline in quality of vegetation and soil, such as the replacement of grass with desert shrubs," he says. "Desertification can be caused by environmental changes like a decline in rainfall or an increase in temperature; overgrazing; or even, as some experiments are showing, the increase of atmospheric carbon dioxide, which gives desert shrubs a competitive advantage over competing grasses."
Monger says desertification can have devastating effects on the land and its people. "For example, the Roman Empire, which was farming northern Africa, lost many of its productive agricultural lands to desertification."
In that case, the changes from farmland to desert were caused by humans. Monger is interested in these changes, but also in the natural cycles of desertification. He wants to know if deserts form and then become vegetative and then form again in a cyclic pattern.
He tries to find an answer in three ways. First, he studies erosion. "Erosion occurs whenever the ground is barren," he says. "If it's bare, the wind is going to blow the soil away, and the rain is going to wash it away." He tries to pinpoint when the erosion ocurred.
Then, he looks at pollen, which leaves a record of vegetative growth. "Pollen makes a wonderful fossil," he says. "Just like you can take an acorn and say this came from an oak tree, you can take a pollen grain and say this came from a creosote bush."
To find out what today's pollen has to say about vegetation, Monger collects and analyzes desert soil. At one study site at the USDA's Jornada Experimental Range located outside Las Cruces, he takes 30 samples in a 30-by-30-meter area four times each year. This site also is part of NMSU's Long-term Ecological Research project funded by the National Science Foundation.
He'll then compare the modern pollen samples to fossilized pollen buried in the soil from thousands of years past. At the Jornada, he can go back as far as 600,000 years by taking samples from a three-story-deep trench, built by NMSU scientists in 1986. Monger calls the trench his time machine, because each buried land surface represents a specific time period.
Finally, he'll look at calcium carbonate crystals or caliche, which form in the soil of arid regions. This, too, tells a tale of changes in vegetation. "Different types of vegetation produce caliche crystals with specific isotope ratios," Monger says.
Putting all the data together, he'll try to reconstruct what has happened over time. "We need to get a sense of how fragile or how resilient these areas are to desertification."
Rehabilitating Ojinaga
The last five years have been hard for the Mexican city of Ojinaga, a community of about 20,000 people located across Rio Grande from Presidio, Texas.
About one-third of the population has been lost to a declining economy and soil salinity problems that make it difficult to grow crops on the area's 20,000 agricultural acres. Trouble handling sewage compounds the region's woes.
Scientists with NMSU's Agricultural Experiment Station are seeking support from private and federal organizations on both sides of the border to help provide a solution for simultaneously clearing up several problems in Ojinaga.
"We're going to try to combine wood production for paper pulp with sewage sludge use, and rehabilitation of salinized agricultural land," says John Mexal, project coordinator and tree physiologist with the Experiment Station.
The project, which still requires funding, includes planting fast- growing eucalyptus trees and irrigating with a combination of sewage effluent and water from the Rio Conchos.
"Eucalyptus trees are good for rehabilitating the land because they absorb excess salts. The wood produced would feed a pulp mill, creating jobs," Mexal says.
Planting eucalyptus on about one-twelfth of the agricultural land would handle the community's sludge. But, the pulp mill could use wood produced on as much as 100 percent of Ojinaga's agricultural land.
This project may someday serve as a training center, because it will incorporate technologies that could be easily transferred to other small, struggling rural communities, Mexal says.
Surveying Mexican Snackers
Both numbers and potato chips were crunched in research that could help American food producers understand potential buyers for their products in Mexico.
Agricultural economists with NMSU's Agricultural Experiment Station asked 300 shoppers in a Chihuahua City mall to stop, shop, and snack. Researchers wanted to know if Mexican consumers' tastes were related to whether foods were "Made in the U.S.A." or "Hecho en Mexico."
"We were trying to develop profiles of people who might be biased towards or against foods produced in the United States," explains Rhonda Skaggs, an agricultural economist with the Experiment Station.
Among economists, those attitudes are known as country-of-origin biases. In Mexico, such preferences are a well-known cultural phenomenon.
With a grant of nearly $50,000 from the U.S. Department of Agriculture, researchers used a realistic scenario for their study. Shoppers completed a taste test, simulated shopping experience, and attitudinal survey about familiar foods.
"We chose snack foods--potato chips and chile salsas--because they're one of the fastest-growing segments of the U.S. export market," says Connie Falk, also an agricultural economist with the Experiment Station. "Also, we wanted our research to relate to some products that could come from New Mexico."
Sometimes, when shoppers ate a chip they thought was American made, it really was. Other times, shoppers were misled to think it was made in Mexico. Next, participants made choices between American and Mexican products of varying prices. Finally, they answered questions about their background, buying habits, and attitudes toward foods from both countries.
Country-of-origin bias was evident in the salsa tests. When salsa had a Mexican label, regardless of where it was actually made, participants said they were more willing to buy it.
American potato chips, whether labeled correctly or as Mexican, were preferred by six of 10 shoppers. Consumers said the lower the price, the more likely they were to buy American potato chips.
Knowing more about who's likely to select salsa or pick potato chips helps marketers put their money where the mouths are. Although American potato chip makers appear to have a window of opportunity to sell their products at reasonable prices, U.S. salsa makers probably don't want to tout their salsas as American made.