Study Examines Biomass Production Impacts on Water Yield for Department of Energy Report

By 2040, one billion tons or more of biomass could be produced each year in the United States, according to the U.S. Department of Energy’s 2016 Billion-Ton Report. Whole trees or materials left behind after logging operations, agricultural crops and crop residue, algae, and even municipal solid waste are sources of biomass that can be used for fuel, energy, heating, and chemicals. But what are the potential effects on environmental sustainability? Federal, academic, and industry scientists followed up with modeling studies examining impacts on soil, water, air quality, biodiversity, and climate and recently published their results in a Volume 2 report that can inform decision making to improve environmental outcomes around biomass production and uses. Eastern Threat Center research hydrologist Ge Sun, postdoctoral researchers Liangxia Zhang and Kai Duan, and Southern Research Station research ecologist Benjamin Rau contributed a chapter on water yield impacts. The researchers used the Water Supply Stress Index model to estimate the effects of potential forest clearcutting and thinning on seasonal and annual total water yields at the watershed and county scales. “Our study suggests that projected biomass removal levels are rather low and may not cause concerns or large benefits to water quantity and supplies at the county level, but the impacts can be significant if biomass harvesting activities are concentrated within a watershed in a county. In such a case, stormflow volume could increase, potentially causing water quality concerns,” says Sun. “Best management practices such as implementing forest riparian buffers may be effective to mitigate negative harvesting effects on stream hydrology and water quality.” Read Volume 2 of the 2016 Billion-Ton Report and related fact sheets, and stay tuned for more news and learning opportunities.