Journals with 2014 NARA publications
Journals with 2014 NARA publications

In 2014, NARA researchers published 25 papers in peer-reviewed journals. These publications help transfer NARA research to a wide audience. Here is a brief narrative to how these peer-reviewed papers complement NARA’s goals and contribute towards evaluating the use of forest residuals as a feedstock to produce chemical products.

NARA goal 1: Sustainable Biojet

A number of papers were published that should help land managers, haulers and logging contractors reduce the cost of moving biomass from slash piles to a conversion facility. Methods to increase truckload density (1), measure the amount of biomass in slash piles (2), and tools to optimize biomass processing and transport (3) were provided.

In the conversion scenario being evaluated by NARA, wood-based simple sugars are extracted through process known as pretreatment and enzymatic hydrolysis and then converted into isobutanol and other chemical products like biojet fuel. NARA researchers published papers that evaluate the performance of sulfite-based (4, 5) and dilute acid (6, 7) pretreatment procedures and on enhancing enzymatic hydrolysis (8). An alternative technology to the sugar-to-isobutanol pathway was presented that converts the simple sugars into volatile fatty acids, many of which have commercial applications (9). Contributions were also made towards understanding how biofuels can be derived from pyrolysis (10).

Long-term efforts to help softwood tree-breeders select future seedlings that benefit traditional timber use and a biofuel and co-product industry were advanced. Two publications describe how phenomics technology can screen large numbers of conifer seedlings for drought and salinity resistance (11, 12). Another publication showed strong evidence that some trees release their simple sugars during pretreatment better than others and that this characteristic is genetically controlled (13).

NARA goal 2: Value Lignin Co-Products

Using the simple sugars from wood residuals to make valuable products leaves a wood byproduct containing a high percentage of lignin. Developing commercial products from the lignin-rich material is an essential component to developing an economically sustainable industry. One publication introduced a method to break-up the lignin molecules (depolymerize) into structures that could more readably be converted into valuable chemical products (14). Other publications described methods to convert the lignin-rich material into epoxy resins (15) and dicarboxylic acids (16).

NARA goal 3: Rural Economic Development

The NARA project is based on the assumption that a wood residuals-to-biofuel and co-product industry and the connected economic development will succeed only if it is socially, economically and environmentally sustainable. To better gage environmental sustainability, publications were produced that evaluate the impact of forest residual removal on soil nutrients (17, 18) and soil compaction (19). Additional publications evaluated the effects of using nitrogen fertilizer on plantation forests (20) and methods to measure soil productivity (21). A significant output tasked to NARA is to develop a comprehensive life cycle assessment (LCA) that compares the greenhouse gas emissions generated from the wood residuals-to-biojet and co-products supply chain to a jet fuel and co-product supply chain based on fossil fuels. This assessment is still in development; however, the first peer-reviewed publication that addresses the methodology used is available (22).

NARA goal 4: Supply Chain Coalitions

Identifying, informing and involving the individuals, businesses and communities who will use NARA’s research to implement a supply chain that develops chemical products from forest residuals is a key component to the project. NARA is developing tools to help stakeholders identify the best locations for depots and biorefineries. One publication outlines a developing method used to rank communities not only for their physical assets and location but also for their likely social acceptance to participate in the emerging supply chain (23).

NARA goal 5: Bioenergy Literacy

Publications that describe NARA’s efforts to enhance the bioenergy literacy of students, educators, professionals and the general public include an evaluation of methods used to gage the effectiveness of the Imagine Tomorrow competition on high-school student’s literacy and career choices (24) as well as a lesson plan for middle school students comparing carbon sequestration to forest products (25).

Other NARA publications

The purpose of this article is to highlight the 2014 peer-reviewed journal articles produced by NARA researchers and place them with the context of NARA’s five goals. In total, 46 peer-reviewed articles have been published since NARA’s inception and numerous other publications have been produced which are listed on the NARA website.

View here for a listing of all NARA produced articles, technical reports, book chapters, educational materials, theses and conference proceedings to date.

View NARA progress reports here.

View supply chain analyses here


Listed below are the publications referred to in this newsletter entry with links to the journals. Many of these articles are further described in previous NARA newsletters.

  1. Zamora R, Sessions J, Smith D, and Marrs G. 2014. Effect of high speed blowing on the bulk density of ground residues. Forest Prod. J. 64(7/8): 290-299. DOI:
  2. Long J and Boston K. An evaluation of alternative measurement techniques for estimating the volume of logging residues.Forest Science 60(1):200-204. DOI:
  3. Zamora RC, Sessions J, Boston K, Murphy G. 2014. Economic optimization of forest biomass processing and transport in the Pacific Northwest. Forest Science [Online Release]. 2014 [Cited Oct 2, 2014]. Available from:
  4. Zhang J, Laguna A, Clemons C, Wolcott MP, Gleisner R, Zhu JY, Zhang, X. Effect of hot-pressing temperature on the subsequent enzymatic saccharification and fermentation performance of SPORL pretreated forest biomass. Bioenerg. Res.[Online Publication]. 2014 [cited 2014 Sept. 10]. Available from:
  5. Zhang C, Houtman CJ, Zhu JY. 2014. Using low temperature to balance enzymatic saccharification and furan formation during SPORL pretreatment of Douglas-fir. Process Biochemistry 49:466-473. DOI: 10.1016/j.procbio.2013.12.017
  6. Alvarez-Vasco C, Guo M, Zhang X. Dilute acid pretreatment of Douglas-fir forest residues: pretreatment yield, hemicellulose degradation, and enzymatic hydrolysability. BioEnergy Research, [Fast track submission online] 2014 (cited 2014, Dec 11] Available from:
  7. Zhang C, Lei X, Scott TC, Zhu JY. 2014. Comparison of dilute acid and sulfite pretreatment for enzymatic saccharification of earlywood and latewood of Douglas fir. Bioenerg. Res 7(1): 326-370. DOI: 10.10007/s12155-013-9276-6
  8. Lou H, Zhou H, Li X, Wang M, Zhu JY, Qiu X. 2014. Understanding the effects of lignosulfonate on enzymatic saccharification of pure cellulose. Cellulose 21:1351-1359. DOI: 10.1007/s10570-014-0237-z
  9. Garrett BG, Srinivas K, Ahring BK. 2014. Design and optimization of a semi-continuous high pressure carbon dioxide extraction system for acetic acid. J. of Supercritical Fluids 95:243-251. DOI:10.1016/j.supflu.2014.08.029
  10. Paulsen AD, Hough BR, Williams CL, Teixeira AR, Schwartz DT, Pfaendtner J, Dauenhauer PJ. 2014. Fast pyrolysis of wood for biofuels: spatiotemporally resolved diffuse reflectance In situ spectroscopy of particles. ChemSusChem 7(3): 765-776. DOI: 10.1002/cssc.201400088
  11. Kirchhoff H. 2014. Structural changes of the thylakoid membrane network induced by high light stress in plant chloroplasts. Phil. Trans. R. Soc. B. 369: 20130225.
  12. Kirchhoff H. 2014. Diffusion of molecules and macromolecules in thylakoid membranes. Biochim. Biophys. Acta, 1837(4):495-502.DOI: 10.1016/j.bbabio.2013.11.003
  13. Geleynse S, Alvarez-Vasco C, Garcia K, Jayawickrama K, Trappe M, Zhang X. 2014. A multi-level analysis approach to measuring variations in biomass recalcitrance of Douglas fir tree samples. BioEnerg. Res. 7(4): DOI:10.1007/s12155-014-9483-z
  14. Xin J, Zhang P, Wolcott MP, Zhang X, Zhang J. 2014. Partial depolymerization of enzymolysis lignin via mild hydrogenolysis over Raney Nickel. Bioresource Technology 155:422-426. DOI: 10.1016/j.biortech.2013.12.092.
  15. Qin J, Liu H, Zhang P, Wolcott M, Zhang J. 2014. Use of eugenol and rosin as feedstocks for biobased epoxy resins and study of curing and performance properties. Polymer International 63(4): 760-765. DOI 10.1002/pi.4588
  16. Ma RS, Guo M, Zhang X. 2014. Selective conversion of biorefinery lignin to dicarboxylic acids. ChemSusChem 7(2): 412-415. DOI: 10.1002/cssc.201300964
  17. James J, Knight E, Gamba V, Harrison R. 2014. Deep soil: quantification, modeling, and significance of subsurface nitrogen. Forest Ecology and Management 336:194-202. DOI:10.1016/j.foreco.2014.10.010
  18. Jandl R, Rodeghiero M, Martinez C, Cotrufo FM, Bampa F, van Wesemael B, Lorenz K, Chabbi A, Miglietta F. 2014. Current status, uncertainty and future needs in soil organic carbon monitoring. Science of the Total Environment, 468-469: 376-383.
  19. Zamora R, Adams P, Sessions J. 2014. Ground-based thinning on steep slopes in western Oregon: soil exposure and strength effects. Forest Science 60(5): 1014-1020. DOI:
  20. Littke KM, Harrison RB, Zabowski D, Briggs DG. 2014. Assessing nitrogen fertilizer response of coastal Douglas-fir in the Pacific Northwest using a paired-tree experimental design. Forest Ecology and Management 330:137-143.
  21. Littke KM, Harrison RB, Zabowski D, Briggs DG, Maguire DA. 2014. Effects of geoclimatic factors on soil water, nitrogen, and foliar properties of Douglas-fir plantations in the Pacific Northwest. Forest Science 60(6): 1118-1130. DOI:
  22. Pierobon F, Ganguly I, Anfodillo T, Eastin I. 2014. Evaluation of Environmental Impacts of Harvest Residue-based Bioenergy Using Radiative Forcing Framework. Forestry Chronicle 90(5): 577-585. DOI: 10.5558/tfc2014-120
  23. Martinkus N, Shi W, Lovrich N, Pierce J, Smith P, Wolcott M. 2014. Integrating biogeophysical and social assets into biomass-to-biofuels supply chain siting decisions. Biomass & Bioenergy 66:410-418. DOI:10.1016/j.biombioe.2014.04.014
  24. Langfitt Q, Haselbach L, Hougham J. Artifact-based energy literacy assessment utilizing rubric scoring. J. Prof. Issues Eng. Educ. Pract. [Online Release]. 2014 [cited 2014 July 1]. Available from:
  25. Schon J, Hougham RJ, Eitel KB, Hollenhorst S. (2014). The value of a tree: comparing carbon sequestration to forest productsScience Scope 37(7): 27–35.