02354naa a2200253 a 450000100080000000500110000800800410001902400370006010000280009724500870012526000090021250002110022152013740043265000220180665300140182865300150184265300160185765300190187365300190189265300170191170000200192870000260194877301260197410619592021-04-07       2021    bl uuuu     u00u1 u    #d7 a10.1016/j.agwat.2021.1068702DOI1 aBUSTAMANTE-SILVEIRA, M.  aWater footprints of bioethanol cropping systems in Uruguay,h[electronic resource]  c2021  aArticle history: Received 4 June 2020/ Revised 10 March 2021/ Accepted 13 March 2021/ Available online 5 April 2021. Corresponding author: E-mail address: bustamantefagro@gmail.com (M. Bustamante-Silveira).  aABSTRACT: Bioenergy is the most widely used type of renewable energy. However, an assessment of water consumption and  pollution is necessary to determine the water demand of this energy source. The Uruguayan public policy to decarbonize energy sources highlighted the use of bioenergy. In this regard, we analyzed the water footprint (WF) of four bioethanol cropping systems: (1) maize-wheat-sorghum rotation without harvested crop residues (MWS), (2) maize-wheat-sorghum rotation with harvested crop residues (MWS-R), (3) continuous sweet sorghum (Ss), and (4) switchgrass (Sw). In order to assess the WF of bioethanol production, green (WFgreen) and gray  (WFgray) components of crop production were calculated by considering the different volumes of water involved  in evaporation, rainfall, and fertilizer pollution. Annual cropping systems (i.e., MWS, MWS-R, Ss) had the largest  WFs (23.1?30.9 m3 L? 1 ethanol). Switchgrass had the lowest values per hectare and per liter of ethanol  (12,735 m3 (ha yr)? 1 and 3.8 m3 L? 1 ethanol, respectively). The volume required to assimilate phosphorous (P) and  nitrogen (N) fertilizers played a significant role in bioethanol cropping systems. In annual systems, WFgray was  the main fraction (87%) of total WF (WFT). Averaged across all cropping systems, WFgray related to P was 13  times larger than WFgray related to N.  aENERGIA RENOVABLE  aBIOENERGY  aGRAY WATER  aGREEN WATER  aHUELLA HIDRICA  aINTESIFICATION  aSOIL EROSION1 aSIRI-PRIETO, G.1 aCARRASCO-LETELIER, L.  tAgricultural Water Management, 30 June 2021, Volume 252, Article 106870. Doi: https://doi.org/10.1016/j.agwat.2021.106870