The data herein were used to trace the source and depth of nutrient uptake in two mountainous temperate forest ecosystems in southern Germany (Conventwald/Black Forest and Mitterfels/Bavarian Forest). Presented are phosphorus (P) concentrations from various P fractions of soil, saprolite, weathered bedrock and unweathered bedrock samples from drilling cores (depth: 20 m, site Conventwald (CON), and 30 m, site Mitterfels (MIT)) obtained by sequential extractions following the Hedley fractionation method. Further, the dataset contains strontium (Sr) and beryllium (Be) isotope data from drilling cores mentioned above. 87Sr/86Sr data are provided for bulk samples of forest floor, soil, saprolite, weathered bedrock, and unweathered bedrock. For soil and saprolite samples, additional Sr isotope ratios of the water-soluble and the exchangeable Sr fractions are provided.
87Sr/86Sr, beryllium concentrations (measured by Quadrupole-ICP-MS) and 10Be(meteoric)/9Be data from living leaves, needles, and stem wood (heartwood and sapwood of Fagus sylvatica and Picea abies) from both study sites are reported. Beryllium concentrations (measured by ICP-OES) and isotope ratios of amorphous oxides sequentially extracted from soil and saprolite at CON and MIT are provided. Soil pH at CON and MIT is also provided. Compiled concentrations of K, Ca, Mg and P and total deposition rates of atmospheric dust deposition are also included in the dataset.
The data presented here stem from sampling campaigns and analyses described in Uhlig et al. (2020) to which they are supplementary material to. Samples were mainly processed in the Helmholtz Laboratory for the Geochemistry of the Earth Surface (HELGES), the University of Bonn (P Hedley fractionation) and the University of Cologne - Centre for Accelerator Mass Spectrometry (AMS) (10Be measurements).
Tables supplementary to the article, including data quality control, are provided in pdf and xls formats. In addition, data measured in the course of the study are also provided as machine readable ASCII files. All samples are indexed with an International Geo Sample Number (IGSN). Sample metadata can be viewed by adding the IGSN to the “http://igsn.org/” URL (e.g. igsn.org/GFDUH00LT).
We provide geochemical background data on the partitioning and cycling of elements between rock, saprolite, soil, plants, and river dissolved and solid loads from at three sites along a global transect of mountain landscapes that differ in erosion rates – an “erodosequence”. These sites are the Swiss Central Alps, a rapidly-eroding post-glacial mountain belt; the Southern Sierra Nevada, USA, eroding at moderate rates; and the slowly-eroding tropical Highlands of Sri Lanka.
The backbone of this analysis is an extensive data set of rock, saprolite, soil, water, and plant geochemical data. This set of elemental concentrations is converted into process rates by using regolith production and weathering rates from cosmogenic nuclides, and estimates of biomass growth. Combined, they allow us to derive elemental fluxes through regolith and vegetation. The main findings are: 1) the rates of weathering are set locally in regolith, and not by the rate at which entire landscapes erode; 2) the degree of weathering is mainly controlled by regolith thickness. This results in supply-limited weathering in Sri Lanka where weathering runs to completion, and kinetically-limited weathering in the Alps and Sierra Nevada where soluble primary minerals persist; 3) these weathering characteristics are reflected in the sites’ ecosystem processes, namely in that nutritive elements are intensely recycled in the supply-limited setting, and directly taken up from soil and rock in the kinetically settings; 4) contrary to common paradigms, the weathering rates are not controlled by biomass growth; 5) at all sites we find a deficit in river solute export when compared to solute production in regolith, the extent of which differs between elements but not between erosion rates. Plant uptake followed by litter erosion might explain this deficit for biologically utilized elements of high solubility, and rare, high-discharge flushing events for colloidal-bound elements of low solubility. Our data and the new metrics have begun to serve for calibrating metal isotope systems in the weathering zone, the isotope ratios of which depend on the flux partitioning between the compartments of the Critical Zone. We demonstrate this application in several isotope geochemical companion papers with associated datasets from the same samples.
All samples are assigned with International Geo Sample Numbers (IGSN), a globally unique and persistent Identifier for physical samples. The IGSNs are provided in the data tables and link to a comprehensive sample description in the internet.
The data herein were used to assess the importance of geogenic-derived nutrients on long-term forest ecosystem nutrition in two mountainous temperate forest ecosystems in southern Germany (Conventwald/Black Forest and Mitterfels/Bavarian Forest). Presented are element concentrations of various forest ecosystem compartments along with the soil pH, chemical depletion fractions (CDF), mass transfer coefficients (τ_(X_i)^X), radiogenic Sr isotope ratio (87Sr/86Sr) of soil and saprolite as well as in situ 10Be concentrations of bedload sediment.Element concentrations measured by X-ray fluorescence (XRF) are provided for drilling core samples (depth: 20 m, site Conventwald (CON), and 30 m, site Mitterfels (MIT)) including unweathered parent bedrock (paragneiss) and regolith comprising soil, saprolite and weathered bedrock but also for bedload sediment. Element concentrations were also measured by ICP-OES to determine the element composition of the soil´s and saprolite´s water-soluble, easily exchangeable, carbonate and organic-bound fraction. In addition, ICP-OES derived element concentrations are reported for plant tissues such as needles, leaves, and stem wood comprising heartwood (dead part of wood) and sapwood (living part of wood) of the two tree species European beech (Fagus sylvatica) and Norway spruce (Picea abies).Along with the chemical composition of soil and saprolite calculated weathering indices such as the chemical depletion fraction (CDF) and the mass transfer coefficient (τ_(X_i)^X) are reported for regolith and bedrock. Further, the dataset contains phosphorus (P) concentrations measured by ICP-OES and UV spectrometry from various P fractions obtained by sequential extractions following the Hedley fractionation method. Additionally, the pH of soil and saprolite measured by a pH meter as well as the radiogenic Sr isotope ratio, namely 87Sr/86Sr measured by MC-ICP-MS for bulk bedrock and regolith are reported in the dataset. Finally, to estimate the landscapes lowering rate (total denudation) in situ 10Be concentrations were measured by accelerator mass spectrometry (AMS) on bedload sediment at the outlet of the catchment.The data presented here stem from sampling campaigns described in Uhlig et al. (2019) to which they are supplementary material to. Samples were mainly processed in the Helmholtz Laboratory for the Geochemistry of the Earth Surface (HELGES) and the GFZ section of Inorganic and Isotope Geochemistry (XRF analyses), the University of Bonn (P Hedley fractionation), and the University of Cologne - Centre for Accelerator Mass Spectrometry (AMS) (10Be measurements).This dataset represents the supplementary material to Uhlig et al. (2019). Tables (including data quality control) supplementary to the article are provided in pdf and xls formats. In addition, data measured in the course of the study is given in machine readable ASCII files. All samples are indexed with an International Geo Sample Number (IGSN). Sample metadata can be viewed by adding the IGSN to the “http://igsn.org/” URL (e.g. igsn.org/GFDUH00LT).