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Sediment-related environmental problems pose a serious threat to sustainable land management in many developing countries, including Iran. Information regarding sediment sources represents a key requirement from the management perspective since identification of sediment sources is a precursor to the design of effective sediment management and control strategies. The fingerprinting approach has increasingly been adopted as an alternative to assembling such information. A wide range of fingerprint properties has been used as a means of discriminating potential sediment sources. However, determining the ability of these properties is very important in the design of cost-effective catchment management strategies before each study. This contribution addresses the ability of two acid extractable metals (Co and Cr) that were used extensively in previous studies to be used to differentiate sediment sources. The results of the statistical analysis demonstrate that no single property is capable of classifying the source material samples into the correct source categories at the Amrovan drainage basins. In the case of the Atary drainage basin, Cr and Co were found in only 47.5 and 43.8% of the source material samples respectively. According to the result obtained, it is recommended that acid extractable metals for sediment sources differentiation in conjunction with the composite of other properties to improve sediment source discrimination.

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Today fingerprinting techniques are increasingly adopted as an alternative and more direct and reliable means of assembling sediment source information. One of the principal assumptions of sediment fingerprinting is that potential catchment sediment sources can be distinguished on the basis of their physical, geochemical and biological properties or fingerprint properties. However, while the source fingerprinting approaches necessarily assume conservative behaviour of the fingerprint properties, some in-stream alteration of these properties during both transport and short-term storage is probably inevitable. This potential limitation must be judged in the context of the problems associated with the use of sediment fingerprinting techniques. Samples of sediment source and reservoir sediment collected during the present study have been used to determine the conservative behavior of fifteen fingerprint properties. Comparison of fingerprinting property concentrations of intensive properties used in fingerprinting indicates there is an increase in content of the N, P, C, Co, Cr, clay minerals (smectite, illite, kaolinite), Low Frequency Magnetic Susceptibility (XLF) and Frequency Dependent Magnetic Susceptibility (XFD) and decrease in clay mineral chlorite and base cations Ca, Mg, Na and K. The results indicate that N, Na and smectite properties have no significant difference in reservoir sediment samples than that in sediment source samples and therefore are useful for fingerprinting investigations in these catchments.