论文信息 - Post-European settlement impacts on erosion and land degradation: a case study using farm reservoir sedimentation in the Eastern Cape, South Africa

Post-European settlement impacts on erosion and land degradation: a case study using farm reservoir sedimentation in the Eastern Cape, South Africa

We present data from a farm reservoir constructed in 1843, which retains a complete and undisturbed sedimentary record exceeding 4 m in depth. A small number (27) of potential sediment sources were sampled and characterised by their mineral magnetic fingerprints. Similar signatures were measured on the reservoir sediments. While yet to be dated, analysis of mineral magnetic properties of the reservoir sediments suggest that they contain significant quantities of super-paramagnetic minerals produced by pedogenesis, but are not strongly overprinted by magnetic signatures that could be attributed to bacterial magnetite or greigite produced within the reservoir. Preliminary results from the source tracing show that the sediments are probably derived from colluvial topsoils punctuated by inputs from river channels or badlands

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