This book takes an in-depth look at the theory and methods inherent in the tracing of riverine
sediments. Examined tracers include multi-elemental concentration data fallout radionuclides
(e.g. 210Pb 137Cs 7Be) radiogenic isotopes (particularly those of Pb Sr and Nd) and
novel (non-traditional) stable isotopes (e.g. Cd Cu Hg and Zn) the latter of which owe
their application to recent advances in analytical chemistry. The intended goal is not to
replace more 'traditional' analyses of the riverine sediment system but to show how tracer
fingerprinting studies can be used to gain insights into system functions that would not
otherwise be possible. The text then provides researchers and catchment managers with a
summary of the strengths and limitations of the examined techniques in terms of their temporal
and spatial resolution data requirements and the uncertainties in the generated results. The
use of environmental tracers has increased significantly during the past decade because it has
become clear that documentation of sediment and sediment-associated contaminant provenance and
dispersal is essential to mitigate their potentially harmful effects on aquatic ecosystems.
Moreover the use of monitoring programs to determine the source of sediments to a water body
has proven to be a costly labor intensive long-term process with a spatial resolution that is
limited by the number of monitoring sites that can be effectively maintained. Alternative
approaches including the identification and analysis of eroded upland areas and the use of
distributed modeling routines also have proven problematic. The application of tracers within
riverine environments has evolved such that they focus on sediments from two general sources:
upland areas and specific localized anthropogenic point sources. Of particular importance to
the former is the development of geochemicalfingerprinting methods that quantify sediment
provenance (and to a much lesser degree sediment-associated contaminants) at the catchment
scale. These methods have largely developed independently of the use of tracers to document the
source and dispersal pathways of contaminated particles from point-sources of anthropogenic
pollution at the reach- to river corridor-scale. Future studies are likely to begin merging the
strengths of both approaches while relying on multiple tracer types to address management and
regulatory issues particularly within the context of the rapidly developing field of
environmental forensics.
