A six-year study of grain crops in the Pacific Northwest says climate change is likely to boost dryland wheat by speeding the hardy crop toward maturity, reports Capital Press. Meanwhile, the journal Science says researchers credit 27 percent of the increase in corn yields over the past three decades to gains in the amount of sunlight that reached farm fields, possibly related to pollution controls.
Some 279 researchers at state universities in Idaho, Oregon and Washington state participated in a study of the likely impact on their region by climate change, which is expected to bring drier and warmer summers and slightly wetter winters, said Capital Press. Professor Claudio Stockle of Washington State University said rising levels of carbon dioxide would promote crop growth and more efficient use of water. “This effect, sometimes referred to as ‘CO2 fertilization,’ might mean that the future of dryland agriculture is better than it is assumed to be when considering climate warming alone,” he said.
Milder winters and warmer springs would spur plant growth, according to a study by Stockle. If they mature sooner, winter and spring wheat crops would avoid the damage of summer heat, said Capital Press.
Measurement of “solar brightening” suggest a new factor in corn yields beyond the usual list of improved genetics and sophisticated farming practices, said Science. “Many suspect crops in industrialized Western countries have been getting more light since the 1980s thanks to clean air regulations that brought down emissions of aerosols, which scatter and absorb solar radiation.” An implication: Forecasts of future yield increases, which are based in part on gains of the past, may not be reliable.
“Several factors are believed to cause solar brightening, but their relative importance and future outlook are unknown, making prediction of continued solar brightening and its future contribution to yield gain uncertain,” says the study published in Nature Climate Change.