The impacts of Miscanthus × giganteus production on the Midwest US hydrologic cycle
Open accessAbstract
Abstract Perennial grasses are being considered as candidates for biofuel feedstocks to provide an alternative energy source to fossil fuels. Miscanthus × giganteus (miscanthus), in particular, is a grass that is predicted to provide more energy per sown area than corn ethanol and reduce net carbon dioxide emissions by increasing the storage of carbon belowground. Miscanthus uses more water than Zea mays (maize), mainly as a result of a longer growing season and higher productivity. Conversion of current land use for miscanthus production will likely disrupt regional hydrologic cycles, yet the magnitude, timing, and spatial distribution of effects are unknown. Here, we show the effects of five different scenarios of miscanthus production on the simulated Midwest US hydrologic cycle. Given the same historic precipitation observations, our ecosystem model simulation results show that on an annual basis miscanthus uses more water than the ecosystems it will likely replace. The actual timing and magnitude of increased water loss to the atmosphere depends on location; however, substantial increases only occur when miscanthus fraction cover exceeds 25% in dry regions and 50% in nearly all of the Midwest. Our results delineate where large‐scale land use conversion to perennial biofuel grasses might deplete soil water resources. Given the fact that some watersheds within the Midwest already have depleted water resources, we expect our results to inform decisions on where to grow perennial grasses for biofuel use to ensure sustainability of energy and water resources, and to minimize the potential for deleterious effects to water quantity and quality.
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Evapotranspiration is likely to impact local water resources and ecosystems.
“evapotranspiration is likely to impact local water resources and ecosystems (de Fraiture & Berndes, 2008;Vanloocke et al., 2010)”
From A multi‐criteria based review of models that predict environmental impacts of land use‐change for perennial energy crops on water, carbon and nitrogen cycling (2013) · cites this paper as Vanloocke et al., 2010
Agricultural GHG emissions and evapotranspiration are separate issues in terms of impact scale.
“This may be because agricultural GHG emissions and evapotranspiration are separate issues in terms of impact scale; evapotranspiration is likely to impact local water resources and ecosystems (de Fraiture & Berndes, 2008;Vanloocke et al., 2010); whereas GHG emissions are a global issue in terms of climate change (Dondini et al., 2009).”
From A multi‐criteria based review of models that predict environmental impacts of land use‐change for perennial energy crops on water, carbon and nitrogen cycling (2013) · cites this paper as Vanloocke et al., 2010
A C4 perennial such as Miscanthus may cause greater evapotranspiration than a C3 annual due to high productivity and long growing season increasing transpiration, and increased interception and evaporation.
“Although photosynthesis type is important, a C4 perennial such as Miscanthus may cause greater evapotranspiration than a C3 annual (McKendry, 2002;Smeets et al., 2009), due to high productivity and long growing season increasing transpiration, and increased interception and evaporation (McKendry, 2002;Vanloocke et al., 2010).”
From A multi‐criteria based review of models that predict environmental impacts of land use‐change for perennial energy crops on water, carbon and nitrogen cycling (2013) · cites this paper as Vanloocke et al., 2010
Evapotranspiration varies with land use, and there are significant differences between perennials and annuals.
“Evapotranspiration (ET) also varies with land use, and there are significant differences between perennials and annuals.”
From A multi‐criteria based review of models that predict environmental impacts of land use‐change for perennial energy crops on water, carbon and nitrogen cycling (2013) · cites this paper as Vanloocke et al., 2010
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- Authors
- VANLOOCKE, A., BERNACCHI, C. J., & TWINE, T. E.
- Affiliations
- University of Illinois Urbana-Champaign (US)
- Agricultural Research Service (US)
- University of Minnesota (US)
- Corresponding author
- TWINE, TRACY E.
- Venue
- GCB Bioenergy
- Publisher
- Wiley
- Published
- 2010-07-11
- Volume
- 2
- Issue
- 4
- Pages
- 180-191
- ISSN
- 1757-1693 (ISSN-L)
- 1757-1707
- OpenAlex
- W2123596417
- Cited by
- 150
- References
- 63
- Citations by year
- 2026: 2 · 2025: 6 · 2024: 3 · 2023: 1 · 2022: 6 · 2021: 7 · 2020: 4 · 2019: 5 · 2018: 8 · 2017: 12 · 2016: 13 · 2015: 16 · 2014: 16 · 2013: 22 · 2012: 16
- FWCI
- 34.67
- Type
- journal article
- Language
- en
- Open access
- bronze
- doi.org
- Locations
- GCB Bioenergy (publishedVersion)
- Funders
- Energy Biosciences Institute
- University of Illinois at Urbana-Champaign
- Topics
- Life Sciences › Agricultural and Biological Sciences › Agronomy and Crop Science › Bioenergy crop production and management
- Physical Sciences › Environmental Science › Water Science and Technology › Hydrology and Watershed Management Studies
- Physical Sciences › Environmental Science › Global and Planetary Change › Plant Water Relations and Carbon Dynamics
- Keywords
- Miscanthus × giganteus, perennial grasses, biofuel feedstock, land use conversion, water cycle, soil water depletion, water consumption, carbon sequestration, maize, Midwestern United States, ecosystem modeling, water resources sustainability
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