Dominguez et al.Aeolian Remobilisation of Tephra Fallout deposit features (morphology and structures) alone are insufficient to interpret transport mechanisms, their combination suggests that whilst saltation is the most common particle transport mechanism, suspension and creep also play an important role. As well as inferring transport mechanisms from this combined approach, we also demonstrate how the correlation of the primary volcanic source with the associated remobilised deposits is fundamental to our understanding of the life cycle of volcanic ash.

Quantitative estimation of the material transported by the wind under fi eld conditions is essential for the study and control of wind erosion. A critical step of this calculation is the integration of the curve that relates the variation of the amount of the material carried by the wind with height. Several mathematical procedures have been proposed for this calculation, but results are scarce and controversial. One objective of this study was to assess the effi ciency of three mathematical models (a rational, an exponential, and a simplifi ed Gaussian function) for the calculation of the mass transport, as compared to the linear spline interpolation. Another objective of this study was to compare the mass transport calculated from fi eld measurements obtained from a minimum of three discrete sampling heights with measurements of nine sampling heights. With this purpose, wind erosion was measured under low surface roughness conditions on an Entic Haplustoll during 25 events. The rational function was found to be mathematically limited for the estimation of wind eroded sediment mass fl ux. The simplifi ed Gaussian model did not fi t to the vertical mass fl ux profi le data. Linear spline interpolation generally produced higher mass transport estimates than the exponential equation, and it proved to be a very fl exible and robust method. Using different sampling arrangements and different mass fl ux models can produce differences of more than 45% in mass transport estimates, even under similar fi eld conditions. Under the conditions of this study, at least three points between the soil surface and 1·5 m high, including one point as closest as possible to the surface, should be sampled in order to obtain accurate mass transport estimates. Additionally, the linear spline interpolation and the non-linear regression using an exponential model, proved to be mathematically reliable methods for calculating the mass transport.

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