Scale linkage and contingency effects of field-scale and hillslope-scale controls of long-term soil erosion: Anthropogeomorphic sediment flux in agricultural loess watersheds of Southern Germany

摘要: Abstract Agricultural landscapes with a millennial-scale history of cultivation are common in many loess areas central Europe. Over time, patterns erosion and sedimentation have been continually modified via the variable imposition anthropogenic discontinuities linkages on fragmented hillslope sediment cascades, which eventually caused complicated soilscape pattern. These field records challenge topographically oriented models simple predictions longer-term change spatial by activities. A thorough understanding how form long-term, however, is essential to develop concepts budget, particularly for modeling flux using GIS. In this study I used extensive datasets soil truncation burial typical undulating watershed southern Germany (10 km2, Wetterau Basin, N Frankfurt a.M.). Spatial properties historic flux, as over seven millennia, were evaluated these data. The pattern low-gradient hillslopes area was found be marked statistical near-random varying depth (thickness) overthickened burial. Moreover, it shown that had developed independently from each other did not correlate either gradient or downslope curvature. Hence, any combination (few) nearly preserved, severely truncated completely removed profiles no, some thick cover present, thereby lacking an obvious Here, suggest putting long-term into contextual anthropogeomorphic systems perspective, accommodates components human-induced operating at different scales interpret consequences hillslope-system level. area, system scale intersection finer-scaled managed broader hillslope-scale framework ‘natural’ controls. borders exert control reference sites. brought about growing historical contingency soilscape, because arbitrary changes inherent its socio-agricultural maintenance. Thus, very low-erosivity setting singled out agency connectivity controls flux. Although findings may less true settings, they allow deriving generic conceptual model between subsystems effects Accordingly, resulting balance on-hillslope net storage delivery streams scaling basic physiographic erosivity well degree fragmentation. For Europe fields fundamental units determine appropriate analysis constrain retrodiction prediction changing fluxes point time scales. Methodical implications address adequate sampling strategies record change, result critical review applicability catena concept long-cultivated included. Finally, suggested refined human-controlled involves number research opportunities, linking approaches cultivation-related soilscape.