Skip to content

Study: perennial bioenergy crops show promise

Biofuel production is expected to expand around the world. To understand the effects of the trend scientists must accurately represent biofuel crops in land-surface models. Using observations from biofuel plants in the Midwest, researchers at the U.S. Department of Energy simulated two biofuel perennial plants – miscanthus and switchgrass. The simulations indicate that perennial crops have advantages compared to traditional annual bioenergy crops. They assimilate more carbon dioxide, and require fewer nutrients and less water.

A study at the U.S. Department of Energy constitutes the first attempt to simulate perennial bioenergy crops in the Community Terrestrial System Model. The model is one of the first land models that can evaluate the complex dynamics of biofuel expansion. It incorporates energy, water, land and climate dynamics, and works at local, regional, and global scales.

The study established the foundation for examining the impact of extensive plantations of bioenergy crops on terrestrial hydrological and biogeochemical cycles and the surface energy balance. Researchers implemented miscanthus and switchgrass into the Community Terrestrial System Model, using parameters for photosynthesis, seasonal changes, resource allocation, plant decomposition and carbon cost for nitrogen uptake.

The researchers simultaneously integrated land-management practices. When they validated simulations against site-level measurements, the results showed the model was capable of capturing both overall patterns of carbon and energy fluxes and the plants’ growth from leaf emergence to maturity.

Miscanthus and switchgrass tend to be more productive than a corn-soybean rotation and offer larger net carbon sinks as a result of their longer growing season, larger leaf areas, and above-ground biomass. Compared to annual crops, the perennial crops lead to increased transpiration, reduced annual runoff, and greater carbon uptake.

The model simulations suggest that with greater carbon-dioxide assimilation rates and less demand for nutrients and water, high-yielding perennial crops are promising alternatives to traditional annual crops for bioenergy feedstocks. That includes stabilizing greenhouse-gas concentrations. It also includes environmental benefits from reducing fertilizer application, which alleviates surface water and groundwater contamination.

Although the local-scale simulations shed light on the potential benefits of using the perennial grasses as bioenergy feedstocks, quantifying the consequences of their plantations at larger scales warrants additional investigation. Visit energy.gov for more information.

#pu-email-form-ag-agriview { clear: both; background-color: #fff; color: #222; background-position: bottom; background-repeat: no-repeat; padding: 15px 20px; margin-bottom: 40px; box-shadow: 0px 2px 0px 0px rgba(0,0,0,.05); border-top: 4px solid rgba(0,0,0,.8); border-bottom: 1px solid rgba(0,0,0,.2); } #pu-email-form-ag-agriview, #pu-email-form-ag-agriview p { font-family: -apple-system, BlinkMacSystemFont, “Segoe UI”, Helvetica, Arial, sans-serif, “Apple Color Emoji”, “Segoe UI Emoji”, “Segoe UI Symbol”; } #pu-email-form-ag-agriview h1 { font-size: 24px; margin: 15px 0 5px 0; font-family: “serif-ds”, Times, “Times New Roman”, serif; } #pu-email-form-ag-agriview .lead { margin-bottom: 5px; } #pu-email-form-ag-agriview .email-desc { font-size: 16px; line-height: 20px; margin-bottom: 5px; opacity: 0.7; } #pu-email-form-ag-agriview form { padding: 10px 30px 5px 30px; } #pu-email-form-ag-agriview .disclaimer { opacity: 0.5; margin-bottom: 0; line-height: 100%; } #pu-email-form-ag-agriview .disclaimer a { color: #222; text-decoration: underline; } #pu-email-form-ag-agriview .email-hammer { border-bottom: 3px solid #222; opacity: .5; display: inline-block; padding: 0 10px 5px 10px; margin-bottom: -5px; font-size: 16px; }

No comment yet, add your voice below!


Add a Comment

Your email address will not be published. Required fields are marked *