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Loess in Armenia

This project aims to characterize, map, analyze and date recently discovered loess-palaeosol sequences from NE Armenia. These sequences have proved to be especially rewarding because of their thickness (up to 45 m) and the presence of diagnostic tephra layers. The project seeks to derive a standard profile for NE Armenia and thus for the Lesser Caucasus. We will use luminescence technologies to date the loess sections, environmental magnetism to understand soil development, mineralogy to constrain provenance and weathering-potential, and terrestrial Mollusca and biomarkers to evaluate different vegetation formations.

Pleistozäne und holozäne Landschaftsgeschichte im Kleinen Süden Chiles

Das südchilenische Seengebiet zählt zu den interdisziplinär mit am besten untersuchten Glaziallandschaften der Südhemisphäre.Aus der Rekonstruktion der Gletscherschwankungen dieses Raumes werden weitreichende paläoklimatische Schlüsse gezogen: sie betreffen die Synchronität der Gletscherbewegung auf der Nord- und Südhalbkugel. Allerdings werden diese Interpretationen, die sich meist auf absolutdatierte Chronostratigraphien stützen können, in jüngster Zeit heftig diskutiert. Zur Klärung des Verhaltens der Gletscher im südchilenischen Seengebiet wird der bodenkundlich-geomorphologische Ansatz bislang kaum genutzt. Aktuelle Untersuchungen belegen (1), daß der Aufbau der Moränen teilweise komplizierter ist als bis dato angenommen wurde und (2), daß dieser methodische Ansatz geeignet ist, die postulierte Glazialchronologie kritisch zu überprüfen. Ergänzt durch im Untersuchungsgebiet ebenfalls noch wenig angewandte Methoden, sollen morphologisch-pedologische Profile helfen, den Aufbau der letzteiszeitlichen Moränen genauer zu differenzieren. Damit kann die Basis für Überlegungen, wie den interhemisphären Vergleich von Gletscherschwankungen, substantiell erweitert werden.

INQUA Project 1216 - RAISIN: Rates of soil forming processes obtained from soils and paleosols in well-defined settings

The project RAISIN represents a core project of the Focus Area Group PASTSOILS. One of the major goals of the Focus Area Group will be achieved through RAISIN: Rates of soil forming processes in different climates, obtained from soils and paleosols in settings where climatic conditions and duration of soil development are known, will be assessed and documented. Thus, the project will provide a solid base for future interpretation of paleosols in the frame of palaeo-environmental reconstructions. Numerous data on soil development with time, many of them based on soil chronosequence studies in various regions, have been published in the past decades. The main aim of the project is hence to bring together scientists working on rates of soil-forming processes in different regions of the world to share and discuss their results, review and compare published data and finally produce a document representing the current state of knowledge on soil formation rates in different climates. The outcome of the project will be published in a special issue of Quaternary International to make it available to the scientific public. Thus, a common standard for interpreting paleosols in soil-sediment successions in terms of duration and environmental conditions of soil development will be created. Moreover, gaps in our current knowledge will be identified in the process of reviewing existing data in the frame of the project. This will stimulate future research and possibly lead to collaborative projects aiming on closing the identified gaps step by step.

Reconstruction of fire frequency and landscape history in the Etna region using a combined methodological approach: evidences from charcoals, soils and dendrochronology

The dry summers in Mediterranean areas already facilitate the occurrence of bush and forest fires, which exert a significant effect on landscape evolution and especially on soils. There is a poor understanding of how soil quality (including the mineral and organic part) relates to these climate and vegetation factors. This knowledge gap compromises our ability to predict the response of SOC storage and the mineral part of soils to global change. Results from an existing soil climosequence at the slopes of the Etna show that organic matter accumulation is highest at the lowest altitudes where there is a more intense fire activity. It is so far unknown which effect has had the fire frequency on the different fractions and nature of soil organic matter in these soils. The proposed project will focus on the investigation of labile and stable organic matter fractions in the soils. On the one hand, the fractions will be quantified and characterised. On the other hand, these fractions will be dated using the radiocarbon technique (14C). In addition, soil charcoal will be collected and quantified. Fire frequency and landscape evolution will also be evaluated through dendrochonological investigations of living and dead trees on the north slopes of the Etna volcano.

Soil moisture response, stable water isotope profiles, and trinary images of vertical subsurface flow paths across the evolution of siliceous and calcareous soil in proglacial areas

The data set was collected to identify hydrological processes and their evolution over it time. It consists of several individual files in tabstop delimeted text format. The data set contains the data obtained from deuterium and brilliant blue tracer experiments at two chronosequence studies in the glacier forefield of the Stone Glacier and the Griessfirn in the central Alps, Switzerland. Each chronosequence consisted of four moraines of different ages (from 30 to 13500 years). At each forefield sprinkling experiments with deuterium and dye tracer experiments with blue dye (Brilliant Blue) were conducted on three plots per moraine. The moraines at the forefield of the Stone Glacier developed from siliceous parent material and at the forefield of the Griessfirn from calcareous parent material. Data from the siliceous forefield are marked with (S) and data from the calcareous forefield are marked with (C). The data set consist of soil moisture time series and soil water isotope profiles of the sprinkling experiments with deuterium, as well as trinary images of stained vertical subsurface flow paths from the dye tracer experiment. The individual plots per moraine are distinguished via their position relative to one another on the moraine (left, middle, and right, looking upslope). The plots used for the sprinkling experiments were located in close vicinity to the plots used for the dye tracer experiments. For the sprinkling experiments with deuterium each plot (4m x 6m) per age class was equipped with 6 soil moisture sensors. Three of these sensors were installed as a sensor profile at one side of the plot about one meter downslope from the upper plot boundary. The sensors were installed at 10, 30, and 50 cm soil depth. On the other side of the plot, two sensors were placed in 10 cm depth, one opposite to the sensor profile and the second sensor one meter upslope from the lower plot boundary. The sixth sensor was placed at 10 cm depth in the center of the plot. The plots were irrigated on three consecutive days with three different irrigation intensities and deuterium concentrations. Per forefield, the soil moisture data are listed in one file per age class. The file contains for each plot, the time stamp and the soil moisture values of the 6 sensors.

Soil physical and hydraulic properties along two chronosequences of proglacial moraines

The data set ": Soil physical and hydraulic properties along two chronosequences of proglacial moraines" consists of several individual files in tabstop delimeted text format. The data set contains soil physical data from two chronosequences of moraines in glacier forefields in the central Alps, Switzerland. Aim of the study was to investigate the impact of age and parent material on soil physical characteristics. At the forefield of the Stone Glacier the moraines developed from silicate parent material (S) and at the forefield of the Griessfirn from calcareous parent material (C). At each forefield disturbed and undisturbed soil samples were collected from four moraines of different ages and porosity, bulk density, particle size distribution, gravel content, ignition loss, retention curves and unsaturated hydraulic conductivity curves were determined. Per moraine, three sampling sites were identified based on the level of vegetation complexity [low, medium, high] (for details on this vegetation classification see Maier et al., 2019). Two sampling locations spaced 3 to 4 m apart were selected per vegetation complexity at each moraine. These different sampling locations are identified in the files as location 1 and 2. Data sets from the moraines developed from silicate parent material are marked with S and data from the moraines with calcareous parent material are marked with C. For the C forefield bulk density, porosity and ignition loss are listed in a single file. For the S location the ignition loss data is listed in a separate file from the bulk density and porosity data. In each file the sample type, the sample volume, the sample number, the moraine age, the sampling depth, and the level of vegetation complexity are provided. The particle size distributions of the fine earth and the gravel content are also listed in individual files. Again, the sample number, moraine age, vegetation complexity, sampling depth and sampling location are noted in the files. For the retention curves and the unsaturated hydraulic conductivity curves, two files exist for each curve and glacier forefield, which are named accordingly with the glacier forefield identification and type of curve. An overview file for each glacier forefield contains a list with the sample number, moraine age, sampling depth, vegetation complexity and sampling location. The other two files per curve contain the lab measurements. For the retention curve data, the sample numbers link the pressure head [cm] values provided in one file to the corresponding volumetric water content [-] values provided in the other file. The same applies to the hydraulic conductivity curve where the sample number now links the unsaturated hydraulic conductivity [cm/h] to the corresponding pressure head [cm].

River terrace height and width analysis

Climatically formed alluvial river-terrace sequences offer an exceptional opportunity to study valley-width evolution under similar discharge and lithologic conditions. To investigate additional parameters controlling valley width, we globally compiled alluvial-terrace sequences that have been associated with late Quaternary climate changes. All terrace cross-sections that are accepted to our compilation (1) include both valley sides, (2) show absolute values of distance and height, as well as profile location, and, (3) display a minimum of three terrace levels out of which at least one is preserved as a paired terrace. The terrace width and height measurements are summarized in this dataset. The data are presented as Excel and ASCII tables.

Drilling Overdeepened Alpine Valleys (DOVE) - Operational Dataset of DOVE Phase 1

The overarching goal of the Drilling Overdeepened Alpine Valleys (DOVE) project will be to date the age and extent of past glaciations. Formerly-glaciated areas are often characterized by deeply incised structures, often filled by Quaternary deposits. These buried troughs and valleys were formed by glacial overdeepening, likely caused by pressurized subglacial meltwater below warm-based glaciers. Results of this drilling campaign, supported by new dating technologies, will further provide critical data on 'how' and 'at which rate' glacial erosion affects such mountain ranges and their foreland. These processes are also of fundamental importance for evaluating the safety of radioactive waste disposal sites, which are planned in areas of former glaciations. Moreover, results of this project will fill gaps in the knowledge of paleoclimate and atmospheric circulation patterns during past glacial epochs and how these patterns affected ice build-up. The operational data sets include the drill core documentation from the mobile Drilling Information System (mDIS), full round core scans, MSCL data sets, a preliminary core description and the geophysical downhole logging data that were acquired during and subsequent to the drilling operations. All downhole logs and core depth were subject to depth correction to a common depth master (cf. operational report for detailed information). The data are described by two scientific reports, the Operational Report (https://doi.org/10.48440/ICDP.5068.001) and the Explanatory Remarks on the Operational Datasets (https://doi.org/10.48440/ICDP.5068.002).

Experimental data of analogue landscape evolution models

This dataset includes raw data used in the paper by Reitano et al. (2020), focused on the effect of different analogue materials on the mechanical and erosional properties of some defined samples. The samples are mixes of three different analogue materials in various proportions. The experiments have been carried out at Laboratory of Experimental Tectonics (LET), University “Roma Tre” (Rome). Detailed descriptions of the experimental apparatus and experimental procedures implemented can be found in the paper to which this dataset refers. We used the MATLAB toolbox “TopoToolbox” (Schwanghart and Scherler, 2014). Here we present: - Pictures recording the evolution of the models. - Laser scans used for further analysis. - Scripts created ad hoc by the authors and used for analyzing and plotting the data. A detailed methodological description can be found in the associated "2020-021_Reitano-et-al_Dataset decription" pdf file.

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