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We explore the assumption that uplift drives erosion and hence, more dissected (eroded) terrains may indicate areas subject to more intense uplift than others, especially if other factors such as elevation and geology can be demonstrated as inconsistent with the spatial pattern of dissection. Geomorphometry and statistics are employed to recognize the enhanced erosional signal within a medium-altitude mountain terrain of the Sudetes in Central Europe, considered as a representative for moderately uplifted areas of complex bedrock diversity. This signal is understood as a meso-scale reflection of relief properties, whereas the recognition of homogeneous terrain units, different in terms of strength of erosional signal, is carried out by means of multi-criteria terrain classification, involving Principal Component Analysis and k-means grouping. Four groups covering 45% of the area have been identified. They were quantitatively compared with independent variables of altitude, lithology, structural units and rock strength, and also assessed in relation to rainfall pattern. It is concluded that their dependence on altitude and geology is only partial. Then, three types of dissected terrain are distinguished and interpreted in terms of uplift intensity, rock strength as a factor modulating erosional response to uplift and timescale. The spatial distribution of these types of terrain indicates several isolated 'hot spots' of erosional dissection on predominantly strong rocks, linked by less elevated areas, underlain by rocks of variable strength. The former are considered as having longer history of uplift and dissection, dated back to the late Palaeogene, whereas the latter record more recent history of endo -exogenic interactions, possibly since the late Miocene. The presence of canyon-like valleys incised into planar or gently sloping relief may indicate the most recent pulse of relief rejuvenation. The procedure proposed in the paper is suitable to be used in various settings, given that good quality topographic data are available. • Areas highly dissected by erosion identified through multi-variate relief classification. • Altitude, lithology and rock strength only partially explain the spatial pattern of dissection. • Different timing of uplift inferred from patterns of erosional dissection. [ABSTRACT FROM AUTHOR]

Abstract: Our understanding about the regional variation of Sediment Yield (SY) in Europe and its scale dependency currently relies on a limited number of data for mainly larger river systems. SY is the integrated result of all erosion and sediment transporting processes operating in a catchment and is therefore of high value for environmental studies and monitoring purposes. Most global assessments of SY consider catchment area (A), climate and topography as the main explanatory variables. However, it is still unclear if these factors also control regional variations of SY within Europe. This paper aims at bridging this gap. Therefore, we i) present a large database of SY-values which was constructed through an extensive literature review; ii) describe the spatial patterns of SY across Europe; and iii) explore its relation with A, climate, and topography. In total, sediment yield data from 1794 different locations throughout Europe were collected (507 reservoirs and 1287 gauging stations), representing a minimum of 29,203 catchment-year data. Only SY-data measured at gauging stations or derived from reservoir siltation rates over a period of a minimum of one year were included in the database. This database comprises a large range of catchment areas (A): i.e from small upland catchments (≥0.01km²) to major European river basins (≤1,360,000km²). An overview of the collected SY-data is provided and sources of uncertainty on the available data are discussed. Despite potentially large uncertainties on several of the individual SY-values, analysis of this database indicates clear spatial patterns of SY in Europe. The temperate and relatively flat regions of Western, Northern and Central Europe generally have relatively low SY-values (with ca. 50% of the SY< 40tkm−2 yr−1 and ca. 80% of the data <200tkm−2 yr−1), while Mediterranean and Mountainous regions generally have higher SY-values (with around 85% of the SY-data >40tkm−2 yr−1 and more than 50% of the data >200tkm−2 yr−1). These differences are attributed to a combination of factors, such as differences in climate, topography, lithology and land use. Although larger differences in SY were found between the climatic regions than between topographic zones, it is currently difficult to identify the individual importance of the various controlling factors of SY. SY–A relationships were calculated for the entire dataset and for subgroups stratified according to the measurement method (gauging stations or reservoir surveys), range of the catchment area, climatic region, topographic zone of the river outlet, and major European river system. Although typically a negative relationship between SY and A is expected due to a decrease in topsoil erosion rates on more gentle slopes and an increase in sediment deposition with an increase in catchment size, this relationship was found to be generally very weak and subject to a lot of scatter. Furthermore, results illustrate important differences in scale dependency: whereas a weak but significant negative trend is generally observed for the temperate and relatively flat regions, no significant or even positive trends were observed in mountain regions and Mediterranean Europe. When only larger river catchments (i.e. >100km² and especially >10,000km²) are considered, catchment area exerted a larger control on SY. These findings confirm previous studies and indicate that the relationship between SY, spatial scale and other controlling factors is often complex and non-linear. [Copyright &y& Elsevier]