The impact of considering land intensification and updated data on biofuels land use change and emissions estimates.

Details

• Creators:
  Taheripour, Farzad ; Zhao, Xin ; Tyner, Wallace E.
• Corporate Contributors:
  BioMed Central
• Subject/TRT Terms:
  • Biomass fuels
  • Exhaust gases
  • Greenhouse gases
  • Land use
  • Land use change
  • Biofuel emissions
  • Intensive versus extensive margin
  • GTAP model and database
• Publication/ Report Number:
  Biotechnol Biofuels (2017) 10:191
• Resource Type:
  Tech Report
• Right Statement:
  Creative Commons Attribution 4.0 International License. http://creativecommons.org/licenses/by/4.0/
• Geographical Coverage:
  United States
• Corporate Publisher:
  BioMed Central
• Abstract:
  Background: The GTAP model has been used to estimate biofuel policy induced land use changes and consequent ; GHG emissions for more than a decade. This paper reviews the history of the model and database modifications and ; improvements that have occurred over that period. In particular, the paper covers in greater detail the move from the ; 2004 to the 2011 database, and the inclusion of cropland intensification in the modeling structure. ; Results: The results show that all the changes in the global economy and agricultural sectors cause biofuels induced ; land use changes and associated emissions can be quite different using the 2011 database versus 2004. The results ; also demonstrate the importance of including land intensification in the analysis. The previous versions of GTAP and ; other similar models assumed that changes in harvested area equal changes in cropland area. However, FAO data ; demonstrate that it is not correct for several important world regions. The model now includes land intensification, ; and the resulting land use changes and emission values are lower as would be expected. ; Conclusions: Dedicated energy crops are not similar to the first generation feedstocks in the sense that they do not ; generate the level of market-mediated responses which we have seen in the first-generation feedstocks. The major ; market-mediated responses are reduced consumption, crop switching, changes in trade, changes in intensification, ; and forest or pasture conversion. These largely do not apply to dedicated energy corps. The land use emissions for cellulosic ; feedstocks depend on what we assume in the emissions factor model regarding soil carbon gained or lost in ; converting land to these feedstocks. We examined this important point for producing bio-gasoline from miscanthus. ; Much of the literature suggests miscanthus actually sequesters carbon, if grown on the existing active cropland or ; degraded land. We provide some illustrative estimates for possible assumptions. Finally, it is important to note the ; importance of the new results for the regulatory process. The current California Air Resources Board carbon scores for ; corn ethanol and soy biodiesel are 19.8 and 29.1, respectively (done with a model version that includes irrigation). The new model and database carbon scores are 12 and 18, respectively, for corn ethanol and soy biodiesel. Thus, the current ; estimates values are substantially less than the values currently being used for regulatory purposes.
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• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/32496/dot_32496_DS1.pdf
• File Type:
  [PDF - 1.51 MB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha-512:5a858f31e82f0b5f43f7a044f96c49e0b539f7b1062426fc20eab3561796fde74f41fccb269da192a8bf7086898e66d3fd37df7574ffc3ce0c24d273cb3ea8dd