Purpose Identifying best practices for sediment fingerprinting or tracing is important to allow the quantification of sediment contributions from catchment sources. Although sediment fingerprinting has been applied with reasonable success, the deployment of this method remains associated with many issues and limitations. Methods Seminars and debates were organised during a 4-day Thematic School in October 2021 to come up with concrete suggestions to improve the design and implementation of tracing methods. Results First, we suggest a better use of geomorphological information to improve study design. Researchers are invited to scrutinise all the knowledge available on the catchment of interest, and to obtain multiple lines of evidence regarding sediment source contributions. Second, we think that scientific knowledge could be improved with local knowledge and we propose a scale of participation describing different levels of involvement of locals in research. Third, we recommend the use of state-of-the-art sediment tracing protocols to conduct sampling, deal with particle size, and examine data before modelling and accounting for the hydro-meteorological context under investigation. Fourth, we promote best practices in modelling, including the importance of running multiple models, selecting appropriate tracers, and reporting on model errors and uncertainty. Fifth, we suggest best practices to share tracing data and samples, which will increase the visibility of the fingerprinting technique in geoscience. Sixth, we suggest that a better formulation of hypotheses could improve our knowledge about erosion and sediment transport processes in a more unified way. Conclusion With the suggested improvements, sediment fingerprinting, which is interdisciplinary in nature, could play a major role to meet the current and future challenges associated with global change. Supplementary information The online version contains supplementary material available at 10.1007/s11368-022-03203-1.

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Mediterranean-climate catchments are characterized by significant spatial and temporal hydrological variability caused by the interaction of natural as well human-induced abiotic and biotic factors. This study investigates the non-linearity of rainfall-runoff relationship at multiple temporal scales in representative small Mediterranean-climate catchments (i.e., <10 km2) to achieve a better understanding of their hydrological response. The rainfall-runoff relationship was evaluated in 43 catchments at annual and event—203 events in 12 of these 43 catchments—scales. A linear rainfall-runoff relationship was observed at an annual scale, with a higher scatter in pervious (R2: 0.47) than impervious catchments (R2: 0.82). Larger scattering was observed at the event scale, although pervious lithology and agricultural land use promoted significant rainfall-runoff linear relations in winter and spring. These relationships were particularly analysed during five hydrological years in the Es Fangar catchment (3.35 km2; Mallorca, Spain) as a temporal downscaling to assess the intra-annual variability, elucidating whether antecedent wetness conditions played a significant role in runoff generation. The assessment of rainfall-runoff relationships under contrasted lithology, land use and seasonality is a useful approach to improve the hydrological modelling of global change scenarios in small catchments where the linearity and non-linearity of the hydrological response—at multiple temporal scales—can inherently co-exist in Mediterranean-climate catchments.

&lt;p&gt;Sediment discharges quantify the pace of landscape evolution and provide a baseline for assessing the impacts of land use changes on soil erosion and sediment discharge. Estimates of the long-term sediment discharge from catchments are important because they provide a measure of basin-averaged erosion rates considering the understanding of erosion and sediment transport is crucial for the sustainable management of water and soil resources. Geomorphologists have currently a significant understanding of sediment delivery in catchments, but there is still a lack of comprehension of how these processes are coupled or decoupled in different types of catchment cascades. Besides, catchment monitoring is complicated by the fact that the relevant processes operate at different temporal and spatial scales. This requires that a nested approach is adopted and that catchment data are collected on the micro to macro scale. This approach has been applied in three gauging stations (3.4, 52.6, and 145 km&lt;sup&gt;2&lt;/sup&gt;) of the Sant Miquel River, a Mediterranean mountainous catchment (151 km&lt;sup&gt;2&lt;/sup&gt;) highly shaped for the human activity (i.e. intensive agriculture, terracing, check dams, channelization) and land abandonment (i.e. revegetation processes). It has an intermittent hydrological regime due to the predominance of karstic processes, despite groundwater from these karstified formations contribute with large water volumes in the middle and downstream part of the catchment. This communication aims to assess the runoff and suspended-sediment transport as well their dynamics (hysteresis) at different time-scales during a 7-year study period for these three nested catchments where water and sediment fluxes were continuously measured and recorded to evaluate the sediment cascade at annual, seasonal and event scales. A discharge (Q; m&lt;sup&gt;3&lt;/sup&gt; s&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;) and suspended sediment concentration (SSC; mg l&lt;sup&gt;&amp;#8722;1&lt;/sup&gt;) database with 56 (3.4 km&lt;sup&gt;2&lt;/sup&gt;), 36 (52.6 km&lt;sup&gt;2&lt;/sup&gt;), and 99 (145 km&lt;sup&gt;2&lt;/sup&gt;) events was used to perform a hysteretic analysis using the &lt;em&gt;h&lt;/em&gt; index developed by Zuecco et al. (2016). Results showed an annual average suspended-sediment yield of 7.5, 40.8, and 26.2 t km&lt;sup&gt;-&lt;/sup&gt;&lt;sup&gt;2&lt;/sup&gt; yr&lt;sup&gt;&amp;#8722;1&lt;/sup&gt; from headwaters to downstream, evidencing transmission loses between the middle and downstream part of the catchment. Clockwise Q-SSC hysteresis loops (with the suspended sediment peak leading the discharge peak) were recorded most frequently (~50 %) at the two headwater sites, being only 31 % in the downstream site where the figure-of-eight pattern (clockwise and anti-clockwise) predominated with 62 % of the events involving that sediment concentration continued to rise despite the falling hydrograph; pattern promoted by the sediment contribution from different tributaries and sources. The need to obtain long-term monitoring programmes provides the key value of this communication to reach a comprehensive understanding about the sediment cascades on catchments at different scales. For this reason, it is necessary to continue exploring the sediment origin dynamics in the future, like an opportunity to reach the scalar integration between processes and techniques to better understand and validate erosion models in Mediterranean catchments.&lt;/p&gt;