The study revealed that technological advances, such as improved crop varieties, irrigation, and fertilizer use, had greatly increased production of major crops and allowed rural populations to remain stable over the past 50 years even as metropolitan populations had soared. Rural counties with extensive irrigation slightly increased their populations, although less-irrigated counties, which offered fewer opportunities for farm-associated work, had decreased theirs slightly, the study said.
Nonetheless, the Great Plains' population was falling behind that of the country as a whole, and their proportion of people over 55 had grown rapidly, the study added. The study identified aging rural populations, reduced water for irrigation and rising fuel prices as long-term threats.
Study authors, William J. Parton and Dennis Ojima of Colorado State University and Myron P. Gutmann of the University of Michigan, noted in their research that farms were becoming more dependent on government subsidies to meet the increased costs of agricultural inputs and fuel. They said plans to develop biofuels could benefit agricultural counties, but increased crop prices also threatened income from livestock production and could accelerate soil erosion while reducing soil carbon.
The study said, declining aquifers and increasing fuel costs represented another potentially worrisome trend, since both had the tendency to add to the cost of irrigation.