Soil erosion and sediment deposition widely affect landscape development, particularly in erosion-prone areas with loessderived soils. Nevertheless, until now, few attempts were made to quantify soil losses and sediment storage over long (centennial or millennial) timescales. In this study, the Holocene alluvial sediment storage in a small river catchment (52 km 2 ) of the Belgian loess belt is estimated, and a preliminary sediment budget for the catchment is presented.In the valley of the Nethen River (c. 13 km long), a detailed survey of the alluvial sediment archive was conducted. Hand augerings and percussion drillings were made along cross-valley transects at 12 locations in the catchment. AMS 14 C dating of peat samples provided a temporal framework for the interpretation of the cores.Results show that the thickness of Holocene sediment deposits in the Nethen valley is 4 to 6m, which corresponds to a total clastic sediment mass of ∼14 × 10 6 t stored in the valley bottom. Three alluvial units could be distinguished and associated with deposition phases from 9600 to 2900 B.C., 2900 B.C. to A.D. 1000 and A.D. 1000 to present. In contrast to the older sediments (units 1 and 2), deposits from the last 1000 year (unit 3) contain little organic matter. They are seldom intercalated with peat layers, and devoid of tufa. Unit 3 reaches a thickness of c. 2m, thereby representing 50% of the Holocene sediment mass stored in the alluvial plain. The mean sedimentation rate in the alluvial plain for this last phase is ∼26t ha − 1 a − 1 , which is about tenfold larger than the sedimentation rates calculated for the older Holocene sediment units. Sediment supply towards the alluvial plain has therefore increased tremendously since Medieval times.These results are in contrast to dating results obtained for colluvial sediments in a nearby dry valley within the catchment of the Nethen, where soil erosion and sediment deposition started in the early Iron Age and was already substantial during the Roman Age. This means that there is a time lag of about one millennium between the onset of high sedimentation rates in the upstream area and high deposition rates in the alluvial plain. This is probably caused by a change in coupling (sediment connectivity) between the plateau, slopes, and rivers. As soil erosion proceeds, first the dry zero-order valleys in the catchment act as sediment traps, and only after these are filled sediment reaches the floodplains. The preliminary sediment budget for the Nethen catchment illustrates that 50% of the sediment that was eroded during the Holocene was stored in colluvial deposits, which are mainly located on footslopes and in dry valley bottoms. Another 29% of the sediment mass is stored in the alluvial plain.

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There are various types of the windblown sediment traps developed for wind tunnel and field studies. One of the main supports expected from these traps is in measuring surface dust concentrations to appropriately derive flux equations. The measurement performance and accuracy of a trap is very important and depends strictly upon the physical characteristics and the behaviors of dust grains with air flows. This paper presents the measurement results of static pressure distribution (SPD) of wind flow around Vaseline-coated slide (VCS) catchers with an aim of finding out whether or not particle trapping efficiency (eta) of the VCS is related to the SPD. The SPD was evaluated by a wind reduction coefficient (R (c)) in a series of wind tunnel experiments with different VCS settings which have different attachment configurations on a pole. Three VCS configurations were considered: a configuration on a circular plastic pole (CPP) and two configurations on wooden square poles (WSP1 and WSP2, respectively). Thus, the primary contribution of this work was to experimentally analyze the effect of the different attachment configurations on the SPD, and the secondary objective was to determine the effect of the SPD on the eta. It was shown that spatial correlation and spatial pattern of the R (c) were different in the surrounding area of each configuration, and ANOVA and DUNCAN tests indicated that eta(s) of WSP1, WSP2, and CPP were different at the significant level of P a parts per thousand currency sign 0.05 with the mean of 0.94 +/- A 0.09, 0.63 +/- A 0.14, and 1.13 +/- A 0.07, respectively. Additionally, the amount of PM20, PM40, PM60, PM80, and PM100 trapped by the configurations of WSP1, WSP2, and CPP considerably varied depending upon the particular aerodynamic circumstances associated with every configuration