There is a better way to grow plants for biofuel

Strategies to produce high yields of biomass for fuels are not a one-size-fits-all proposition, according to a new study. In their 10-year experiment, the researchers explored alternative ways to generate biomass, but with fewer environmental and economic side effects. Moderate treatments with a low rate of nitrogen fertilizer and irrigation water resulted in the best biomass yields and carbon storage—twice the yield and storage of untreated plots. Meanwhile, the more intensively treated plots resulted in 30 percent lower greenhouse gas savings, 10 times greater nitrate leaching, and 120 percent greater loss in plant diversity than their moderately-treated counterparts.While the results indicated that the energy yield from optimal management of prairie grasses was still somewhat lower per hectare than for traditional corn ethanol, the prairie grasses were grown on land too infertile for corn. Moreover, because the grass took much less nitrogen fertilizer than corn and especially because of the high rate of carbon storage in soils, the bioenergy from the optimally grown prairie grasses gave much greater greenhouse savings. All this, with the benefits of ecological restoration.