Lake sediment characterization, a prerequisite for the vulnerabilityassessment of lake ecosystems, demands reliable in situ methods for thecharacterization of the sediment layer composition. A unifiedcharacterization of lake sediments within lake ecotopes (open water, openwater patches within the reed, and the reed) is still a challenge. Eachecotope is covered by different classical scientific disciplines(hydrography and terrestrial remote sensing to soil physics) with theirspecific characterization methods. Recently, a complementary tool thatbridges the gap between land and hydrographic surveying methods wasintroduced. It is a non-acoustic device that combines two soil physicalsensors (a capacitive sensor and a cone penetrometer) and GNSS-positioningin a measuring system (CSPS). The CSPS enables rapid in situ delineation ofwater–mud–consolidated lakebed interfaces. The system was successfullyapplied across ecotopes at the Neusiedler See, a well-mixed shallow lakerich in fine-grained sediments. The geo-referenced vertical CSPS profilesshow ecotope-specific layer composition. The effects of wind-inducedturbidity, particle size, and electrical conductivity were analysed. Thewater–mud interface was precisely delineated at the open water due to apersistent high water content gradient, equivalent to a lutocline. Thepenetration resistance (PR) for open water showed either a shallow andhighly compacted consolidated lakebed or a consolidated lakebed with apartially compacted layer above, while in the reed the PR smoothly increased until reaching the deepest penetration depths.
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