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The identification of sediment sources is important for catchment management, but few studies have been performed in Mediterranean areas. This study uses a multi-proxy sediment fingerprinting approach to explore sources and dynamics of fluvial sediments in a rapidly urbanizing Portuguese peri-urban catchment. X-Ray Fluorescence was used to characterize the elemental geochemistry of sediments collected within the stream network after three storm events in 2012 and 2015. A range of statistical techniques, including hierarchical cluster analysis, was used to identify discriminant sediment properties and similarities between fine bed-sediment samples of tributaries and downstream sites. Quantification of sediment supply from upstream sub-catchments was undertaken using established sediment fingerprinting approaches. The geochemistry of the sediments was found to be influenced by both lithology and land-use changes. In 2012 the sandstone sub-catchment provided 75% of the

Soil level changes over four years at 50 sites in three types of post-fire eucalyptus and pine forest management practices (natural pine seedling regeneration; eucalyptus regrowth from coppiced stumps; and deep-(rip-) ploughed areas planted with eucalyptus seedlings) in the Agueda Basin, Portugal are reported. Average ground lowering at regrowth sites was high during the first year after fire (up to an estimated 18 mm), declining sharply by the third year with vegetation growth and litter cover development. In the first year after rip-ploughing, there was greater surface lowering (up to 27 mm recorded), with recovery within three–four years. This sharp post-ploughing reduction in soil loss is attributed to stone lag development through erosion of fines. Soil erosion resulting from a wildfire—rip-ploughing cycle is estimated to be up to 174 t ha−1, which would lead to ultimate physical degradation for typically thin soils within 50–100 years. Soil surface roughness decreased slightly or remained virtually stable for the moist Agueda Basin stony soil compared with a model of increased roughness for dry Mediterranean stony soils. This difference is attributed to moist conditions encouraging vegetation growth and rapid fermentation of organic matter together with transported sediment infilling surface indentations. The value of a ground-level change approach, and of the soil erosion bridge in particular, in soil erosion studies is discussed. Copyright © 2002 John Wiley & Sons, Ltd.

The impact of different logging techniques on nutrient losses in burnt eucalyptus and pine forests in northern Portugal was investigated. A variety of logging techniques is used in the region resulting in varying amounts of slash debris on the slopes. The efficacy of this litter in reducing soil erosion is well established but less is known about the impact on nutrient losses. Small bounded plots were used to examine the impact of varying amounts of slash debris and pine-needle cover on nutrient losses in overland flow and adsorbed to eroded sediment over 19 months during the first two-three years after fire. Nutrient losses in solution and adsorbed to eroded sediment were substantially higher on burnt terrain due to increased erosion and overland flow generation and high nutrient concentrations at the soil surface in the burned forests. Post-fire logging techniques in eucalyptus forests resulting in large amounts of litter debris on the slopes are effective at reducing eroded sediment nutrient losses but less effective at reducing losses in solution. In pine forests, litter is largely ineffective in reducing solute and sediment nutrient losses. However, a covering of pine needles was shown to be highly effective in reducing eroded sediment nutrient losses and to a lesser extent solute losses. Conservational methods of logging are suggested for both eucalyptus and pine forests in the region. In the absence of such measures, the sustainability of short-rotation eucalyptus forestry is questioned in northern Portugal. Copyright © 2000 John Wiley & Sons, Ltd.