| Popis: |
Numerous small-scale studies show that accelerated erosion processes are driven by human activities over the Holocene. However, as human pressure has been heterogeneous in quality, local case studies are required to assess the influence of agricultural landscape structure on erosion susceptibility and sediment connectivity. We aim to discuss the synchrony between landscape cultivation and erosive signal rise through a study in Burgundy. The vineyard of Mercurey is located in a catchment structurally sensitive to soil loss and cultivated for thousand years.Our methodology includes (i) the reconstruction of the agricultural landscape structure in eight distinct periods in the Holocene, from aerial photographs, historical maps and textual sources; (ii) quantifying the hillslope erosion susceptibility using a RUSLE modelling procedure adapted to past environmental conditions (climate, land use, soil); (iii) the assessment of the sediment connectivity to the stream using the InVEST SDR model based on the connectivity index; (iv) model validation with the analysis of sedimentary deposits observed in the valley bottom and along hillslopes.On the one hand, our results demonstrate that the general level of erosion susceptibility has increased by ca. 680% between the early Holocene and the current situation. Nonetheless, all phases marked by an increase in the cropped area do not have the same response in erosion susceptibility. For instance, a peak in erosion susceptibility during the Middle Ages is concomitant with the spread of vineyard on steep hillslopes, whereas in Roman times and early 19th century, the spatial patterns of agricultural land use (vines on gentle hillslopes, patchwork of grasslands and vines) led to moderate rates of erosion susceptibility. On the other hand, this research reveals that the evolution of sediment connectivity is strongly influenced by the agricultural land management (vine rows orientation, cover crop, dry stone walls). |
