Beryllium-7 (Be) has been used as a sediment tracer to evaluate soil redistribution rates at hillslopes and as a tool to estimate sediment residence time in river systems. A key assumption for the use of Be as a sediment tracer is the rapid and irreversible sorption of Be upon contact with the soil particles. However, recent studies have raised questions about the validity of these assumptions.
View Article and Find Full Text PDFDuring the past decades, land use change in the Lake Victoria basin has significantly increased the sediment fluxes to the lake. These sediments as well as their associated nutrients and pollutants affect the food and water security of millions of people in one of Africa's most densely populated regions. Adequate catchment management strategies, based on a thorough understanding of the factors controlling runoff and sediment discharge are therefore crucial.
View Article and Find Full Text PDFSilica is well known for its role as inducible defence mechanism countering herbivore attack, mainly through precipitation of opaline, biogenic silica (BSi) bodies (phytoliths) in plant epidermal tissues. Even though grazing strongly interacts with other element cycles, its impact on terrestrial silica cycling has never been thoroughly considered. Here, BSi content of ingested grass, hay and faeces of large herbivores was quantified by performing multiple chemical extraction procedures for BSi, allowing the assessment of chemical reactivity.
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