Food imports were not uncommon even in the ancient world. This was evident in a study of New Mexico's Chaco Canyon region which said the inhabitants were not self-sufficient in food for many reasons.
One was the salinity of the soil and the constraint of side-valley areas in the canyon being too small to support more people. These factors point to the hardship in feeding a larger population and making food imports inevitable.
Chaco Canyon, lying in the San Juan Basin of New Mexico, is officially known as the Chaco Culture Natural Historic Park. The study also mentions the residents as claimants to the rich Pueblo culture and having wielded immense political clout over the area.
The details of the study, authored by CU-Boulder scientist Larry Benson were published in the Journal of Archaeological Science.
Construction Boom
According to Benson, the area witnessed a big boom in construction for 300 years from the 9th century and many stone masonry houses and exemplary structures were built. Many ceremonial roads were also constructed linking Chaco with leading Pueblo sites. The author argues that construction materials like timber might have been sourced from the not so distant region of Chuska Slope.
Benson also says that bulk of the corn demand of the ancient people of Chaco might have been fed from the Chuska Slope, some 50 miles away and it was a source of timber used in the construction activities.
"There were timbers, pottery, and chert coming from the Chuska region to Chaco Canyon, so why not surplus corn?" said Benson, who also worked as a U.S. Geological Survey scientist.
In the study, Benson used a tree ring data model created by Jeff Dean, Professor Emeritus at Arizona University. It had details of the annual Chaco Canyon rainfall for 1,100 years and the basic annual rainfall required in growing corn. It was revealed that the minimum requirement of rainfall exceeded just 2.5 percent during that period.
"The important thing about this study is that it demonstrates you can't grow great quantities of corn in the Chaco valley floor," Benson said.
He noted that it can be inferred that either sufficient corn could not be grown in the side canyon tributaries of Chaco to feed several thousand people or the population must have been so small or corn was imported.
The population of Chuska Slope during the time, the author assumes, might have been in the vicinity of 11,000 to 17,000 pueblo people.
The reason for Chuska Slope having surplus corn might have been the result of liberal spring snow melt in Chuska Mountains boosted further by surface water features like wash systems.
The archaeologists are not able to fathom as to why Chaco Canyon was built so much of adversities such as long winters, poor rainfall, and short agriculture seasons.
"I don't think anyone understands why it existed," Benson said and added that at no time in the past, Chaco Canyon was a Garden of Eden.
Drought Threat To Agriculture
Meanwhile, concerns are up that U.S agriculture may face a Dust Bowl-like crisis in terms of drought despite technological advances.
The rising temperatures will be hastening crop losses as in the Dust Bowl of the 1930s and that will be apparent even in normal precipitation periods.
This was revealed in a study, published in Nature Plants. The authors drew these conclusions after simulating the effect of extremely dry weather from the Dust Bowl period on soy, maize, and wheat crops.
"By mid-century, even a normal year in precipitation could be as bad as what we saw in 1936," the study said.
Authored by Michael Glotter and Joshua Elliott of the Center for Robust Decision Making on Climate and Energy Policy at the University of Chicago's Computation Institute, the paper looks at the scenario if innovations in agriculture could protect a replay of history.
