Sources of variability in fatty acid (FA) biomarkers in the application of compound-specific stable isotopes (CSSIs) to soil and sediment fingerprinting and tracing: A review

• Published in: The Science of the total environment Vol. 565; pp. 8 - 27
• Main Authors: Reiffarth, D.G., Petticrew, E.L., Owens, P.N., Lobb, D.A.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.09.2016
• Subjects: Biomarkers - chemistry; Compound-specific stable isotope analysis; CSIA; Environmental Monitoring - methods; Erosion; Fatty Acids - chemistry; Geologic Sediments - chemistry; Land use; Radioisotopes - chemistry; Rivers - chemistry; Soil - chemistry; Tracking; Water quality; TT; Tracking; FRN; V-PDB; WB; SD; PLFA; OC; rubisco; CSIA; VLCFA; Compound-specific stable isotope analysis; CSSI; EA; GC; NLFA; OM; Erosion; DSP; FID; PSE; BMP; KIE; SOC; WUE; LOI; TOC; VOC; IRMS; Land use; CAM; SOM; CV; FAME; GC-C; SOP; PAH; Water quality; PEP; FA; TAG
• ISSN: 0048-9697; 1879-1026
• DOI: 10.1016/j.scitotenv.2016.04.137

Determining soil redistribution and sediment budgets in watersheds is often challenging. One of the methods for making such determinations employs soil and sediment fingerprinting techniques, using sediment properties such as geochemistry, fallout radionuclides, and mineral magnetism. These methods greatly improve the estimation of erosion and deposition within a watershed, but are limited when determining land use-based soil and sediment movement. Recently, compound-specific stable isotopes (CSSIs), which employ fatty acids naturally occurring in the vegetative cover of soils, offer the possibility of refining fingerprinting techniques based on land use, complementing other methods that are currently in use. The CSSI method has been met with some success; however, challenges still remain with respect to scale and resolution due to a potentially large degree of biological, environmental and analytical uncertainty. By better understanding the source of tracers used in CSSI work and the inherent biochemical variability in those tracers, improvement in sample design and tracer selection is possible. Furthermore, an understanding of environmental and analytical factors affecting the CSSI signal will lead to refinement of the approach and the ability to generate more robust data. This review focuses on sources of biological, environmental and analytical variability in applying CSSI to soil and sediment fingerprinting, and presents recommendations based on past work and current research in this area for improving the CSSI technique. A recommendation, based on current information available in the literature, is to use very-long chain saturated fatty acids and to avoid the use of the ubiquitous saturated fatty acids, C16 and C18. [Display omitted] •Compound-specific stable isotopes (CSSIs) of carbon may be used as soil tracers.•The variables affecting CSSI data are: biological, environmental and analytical.•Understanding sources of variability will lead to more robust methods and data.•Recommendations for applying CSSIs to soil and sediment tracing are provided.