Find research datasets worth reusing

opencc-by-4.0Nov 2021View details →

Combined data file for Jilbert et al. "Anthropogenic Inputs of Terrestrial Organic Matter Influence Carbon Loading and Methanogenesis in Coastal Baltic Sea Sediments", Frontiers in Earth Science 9, 2021

The datafile contains all the new raw data presented in the figures in the publication.

opencc-zeroJan 2022View details →

Data from: Watershed classification predicts streamflow regime and organic carbon dynamics in the Northeast Pacific Coastal Temperate Rainforest

Watershed classification has long been a key tool in the hydrological sciences, but few studies have been extended to biogeochemistry. We developed a combined hydro-biogeochemical classification for watersheds draining to the coastal margin of the Northeast Pacific coastal temperate rainforest (1,443,062 km2), including 2,695 small coastal rivers (SCR) and 10 large continental watersheds. We used cluster analysis to group SCR watersheds into 12 types, based on watershed properties. The most important variables for distinguishing SCR watershed types were evapotranspiration, slope, snowfall, and total precipitation. We used both streamflow and dissolved organic carbon (DOC) measurements from rivers (n = 104 and 90 watersheds respectively) to validate the classification. Watershed types corresponded with broad differences in streamflow regime, mean annual runoff, DOC seasonality, and mean DOC concentration. These links between watershed type and river conditions enabled the first region-wide empirical characterization of river hydro-biogeochemistry at the land-sea margin, spanning extensive ungauged and unsampled areas. We found very high annual runoff (mean > 3000 mm, n = 10) in three watershed types totaling 59,024 km2 and ranging from heavily glacierized mountain watersheds with high flow in summer to a rain-fed mountain watershed type with high flow in fall-winter. DOC hotspots (mean > 4 mg L-1, n = 14) were found in three other watershed types (48,557 km2) with perhumid rainforest climates and less-mountainous topography. We described four patterns of DOC seasonality linked to watershed hydrology, with fall-flushing being widespread. Hydro-biogeochemical watershed classification may be useful for other complex regions with sparse observation networks.

opencc-by-4.0Jan 2022View details →

Comparing black-carbon- and aerosol-absorption-measuring instruments – a new system using lab-generated soot coated with controlled amounts of secondary organic matter

A preprint of the publication can be found here: <a href="https://amt.copernicus.org/preprints/amt-2021-214/">AMTD - Response of black carbon and aerosol absorption measuring instruments to laboratory-generated soot coated with controlled amounts of secondary organic matter (copernicus.org)</a> (doi.org/10.5194/amt-2021-214). The files correspond to the raw data sets used for Figures 3 and 4 of the aforementioned publication. The date and start/stop time of the measurements are listed in the file "overview_measurements".

opencc-zeroJan 2022View details →

The role of terrestrial productivity in regulating aquatic dissolved organic carbon concentrations in boreal catchments

The past decades have witnessed an increase in dissolved organic carbon (DOC) concentrations in the catchments of the Northern Hemisphere. Increases in terrestrial productivity may be a reason for the increases in DOC concentration. The aim of this study is to investigate the impacts of increased terrestrial productivity and changed hydrology following climate change on DOC concentrations. We tested and quantified the effects of gross primary production (GPP), ecosystem respiration (RE) and discharge on DOC concentrations in boreal catchments over three years. As catchment characteristics can regulate the extent of rising DOC concentrations caused by the regional or global environmental changes, we selected four catchments with different sizes (small, medium and large) and landscapes (forest, mire and forest-mire mixed). We applied multiple models: Wavelet coherence analysis detected the delay-effects of terrestrial productivity and discharge on aquatic DOC variations of boreal catchments; thereafter, the distributed-lag linear models (DLMs) quantified the contributions of each factor on DOC variations. Our results showed that the combined impacts of terrestrial productivity and discharge explained 62% of aquatic DOC variations on average across all sites, whereas discharge, GPP and RE accounted for 26%, 22% and 3%, respectively. GPP dominated the DOC variations in small catchments (<1 km2), but in large catchments, DOC variations were mainly dependent on discharge. The direction of the relation between GPP and discharge on DOC varied. Increasing RE always made a positive contribution to DOC concentration. This study demonstrated that terrestrial greening and changing hydrology caused by climate change did affect the DOC export from terrestrial to aquatic ecosystems, which improves the mechanistic understanding of surface water DOC regulation in boreal catchments under climate change.

opencc-by-4.0Dec 2021View details →

Maps of soil organic carbon stocks in Brazil

This database was created by Gustavo Vieira Veloso and Lucas Carvalho Gomes 04/06/2022.  Contact: gustavo.v.veloso@gmail.com and lucascarvalhogomes15@hotmail.com  ------------------------------------------------------------------------------------ Maps of soil organic carbon (SOC) stocks in Brazil of the article:  "Modeling and mapping soil organic carbon stocks in Brazil" (doi: 10.1016/j.geoderma.2019.01.007) The dataset is composed of five folders of SOC stocks maps at the standard depths (0–5, 5–15, 15–30, 30–60, and 60–100 cm). The maps are in Geotif format (EPSG 102015) with a spatial resolution of approximately 1 km and include the mean SOC stocks, standard deviation (SD),  coefficient of variation (CV), 0.05 and 0.95 quantiles. The maps are free to use and please cite also the article: Gomes, L.C., Faria, R.M., de Souza, E., Veloso, G.V., Schaefer, C.E.G., & Fernandes Filho, E.I. (2019). Modeling and mapping soil organic carbon stocks in Brazil. Geoderma, 340, 337-350.

opencc-zeroApr 2022View details →

Data from: Decipher soil organic carbon dynamics and driving forces across China using machine learning

The dynamics of soil organic carbon (SOC) play a critical role in modulating global warming. However, the long-term spatiotemporal changes of SOC at large scale and the impacts of driving forces remain unclear. In this study, we investigated the dynamics of SOC in different soil layers across China through the 1980s to 2010s using a machine learning approach and quantified the impacts of the key factors based on factorial simulation experiments. Our results showed that the latest (2000-2014) SOC stock in the first meter soil (SOC100) was 80.68 ± 3.49 Pg C, of which 42.6% was stored in the top 20 cm, sequestrating carbon with a rate of 30.80 ± 12.37 g C m-2 yr-1 since the 1980s. Our experiments focusing on the recent two periods (2000s and 2010s) revealed that climate change exerted the largest relative contributions to SOC dynamics in both layers and warming or drying can result in SOC loss. However, the influence of climate change weakened with soil depth, while the opposite for vegetation growth. Relationships between SOC and forest canopy height further confirmed this strengthened impact of vegetation with soil depth, and highlighted the carbon sink function of deep soil in mature forest. Moreover, our estimates suggested that SOC dynamics in 71% of topsoil were controlled by climate change and its coupled influence with environmental variation (CE). Meanwhile CE and the combined influence of climate change and vegetation growth dominated the SOC dynamics in 82.05% of the first meter soil. Additionally, the national cropland topsoil organic carbon increased with a rate of 23.6 ± 7.6 g C m-2 yr-1 since the 1980s, and the widely applied nitrogenous fertilizer was a key stimulus. Overall, our study extended the knowledge about the dynamics of SOC and deepened our understanding about the impacts of the primary factors.

opencc-zeroApr 2022View details →

Data from: Loamy sand soil approaches organic carbon saturation after 37 years of conservation tillage

This is digital research data corresponding to a published manuscript, Loamy sand soil approaches organic carbon saturation after 37 years of conservation tillage. Conservation tillage is reported to increase soil organic carbon (SOC) and total nitrogen (TN) contents, but long-term (>30 yr) field results quantifying the responses in Coastal Plain Ultisols are sparse. The distribution, accumulation, and topsoil storage of SOC and TN after 37 yr of crop production using conventional (CvT) or conservation tillage (CnT) on a Norfolk loamy sand (fine-loamy, kaolinitic, thermic, Typic Kandiudults) were quantified. Soil samples were collected annually from the 0−5-, 5−10-, and 10−15-cm depth increments beneath corn (Zea mays L.), soybean [Glycine max (L.) Merr.], and cotton (Gossypium hirsutum L.) crops.

opencc-by-4.0May 2022View details →

Carbon isotopic constraints on basin-scale vertical and lateral particulate organic carbon dynamics in the northern South China Sea

This dataset includes:(1) Table S1. Time-series of total mass fluxes, POC content, POC fluxes, Lithogeinic matter content,  lithogenic matter flux, C/N mole ratio,as well as the POC isotopic compositions (δ13C, Fm) for sediment trap intercepted sinking particles (n = 59) in the northern South China Sea basin . (2) Table S2. Time-series monthly dust deposition (dry+wet) at station SCS-N of northern South China Sea basin. (3) Table S3. POC content and radiocarbon isotopic compositions for sediment trap intercepted bulk organic carbon from the South China Sea supplementary to one-year time series (2014-2015) published in Blattmann, T.M. et al., 2018. Geophysical Research Letters, 45(17): 9077-9086. (4) Table S4. Time-series clay mineral content and compositions for sediment trap intercepted sinking particles from the South China Sea supplementary to one-year time series (2009-2010) published in Schroeder A. et al., 2015 . Earth Planet. Sci. Lett. 430: 30–42. The dataset is archived in .xlsx data format, consists of four data files with data size of 34 KB.

opencc-by-4.0Dec 2021View details →

Large dataset of soil organic carbon and topographic derivatives

Abstract: The dataset compiles 840 georeferenced SOC measurements over a 26-ha agricultural field located in southern Ontario, Canada with a sampling density of ~32 points per ha. As SOC is influenced by site topography (i.e., slope and landscape position), each point of the database was associated with a wide range of topographic derivatives. The columns include sample ID, SOC measurement, latitude, Longitude, NDVI values, as well as a set of 54 topographic derivatives (i.e., primary and secondary - see metadat.pdf attached file) with a spatial resolution of a 5 m.

opencc-zeroDec 2021View details →

More soil organic carbon is sequestered through the mycelium-pathway than through the root-pathway under nitrogen enrichment in an alpine forest

Plant roots and associated mycorrhizae exert a large influence on soil carbon (C) cycling. Yet, little was known whether and how roots and ectomycorrhizal extraradical mycelia differentially contribute to soil organic C (SOC) accumulation in alpine forests under increasing nitrogen (N) deposition. Using ingrowth cores, the relative contributions of the root-pathway (RP) (i.e., roots and rhizosphere processes) and mycelium-pathway (MP) (i.e., extraradical mycelia and hyphosphere processes) to SOC accumulation were distinguished and quantified in an ectomycorrhizal-dominated forest receiving chronic N addition (25 kg N ha-1 yr-1). Under the non-N addition, the RP facilitated SOC accumulation, while the MP reduced SOC accumulation. Nitrogen addition enhanced the positive effect of RP on SOC accumulation from +18.02 mg C g-1 to +20.55 mg C g-1 but counteracted the negative effect of MP on SOC accumulation from -5.62 mg C g-1 to -0.57 mg C g-1, as compared to the non-N addition. Compared to the non-N addition, the N-induced SOC accumulation was 1.62~2.21 mg C g-1 and 3.23~4.74 mg C g-1, in the RP and the MP, respectively. The greater contribution of MP to SOC accumulation was mainly attributed to the higher microbial C pump (MCP) efficacy (the proportion of increased microbial residual C to the increased SOC under N addition) in the MP (72.5%) relative to the RP (57%). The higher MCP efficacy in the MP was mainly associated with the higher fungal metabolic activity (i.e., the greater fungal biomass and N-acetyl glucosidase activity) and greater binding efficiency of fungal residual C to mineral surfaces than those of RP. Collectively, our findings highlight the indispensable role of mycelia and hyphosphere processes in the formation and accumulation of stable SOC in the context of increasing N deposition.

opencc-zeroJun 2022View details →

Global Ocean particulate organic phosphorus, carbon, oxygen for respiration, and nitrogen (GO-POPCORN) data from Bio-GO-SHIP cruises

Here, we present the Global Ocean Particulate Organic Phosphorus, Carbon, Oxygen for Respiration, and Nitrogen (GO-POPCORN) dataset with data from the recent Bio-GO-SHIP cruises between 2011 and 2020 supplemented with data from Arctic IERP cruises. The dataset contains 2581 paired measurements of particulate organic carbon, nitrogen, and phosphorus from 70°S to 73°N across all major ocean basins. The dataset also includes 965 measurements of particulate chemical oxygen demand. This new dataset is valuable for improving our understanding of how biological elemental stoichiometry plays a role in regulating both the marine nutrient cycles and the global carbon cycle.

opencc-zeroJul 2022View details →

Contribution of wheat and maize to soil organic carbon in a wheat-maize cropping system: a field and laboratory study

Retention of crop biomass is widely recommended to improve soil organic carbon (SOC). However, the magnitude of contribution of aboveground residues and belowground roots from C3 and C4 crops to SOC is unclear. Data from a 10-year field experiment and a 60-day laboratory incubation were synthesized to identify the respective contribution of C3 (e.g., wheat) and C4 (e.g., maize) residues and roots to SOC, as well as its underlying mechanisms under no-till (NT) using 13C labelling trace in wheat-maize rotations. The field experiment showed that residue retention significantly increased SOC accumulation, and SOC derived from wheat was 126.0% higher than that from maize. Conversion to NT promoted SOC derived from wheat and thus accumulated 17.6% higher SOC stock compared with plow tillage (PT) under residue returning at 0-20 cm soil depth (P<0.05). The data from laboratory incubation revealed the mechanisms that lower priming effects at 0-10 cm depth decreased total mineralization by 91.8% after inputs of wheat residues and roots compared with that of maize residues and roots, especially under NT compared with PT. Priming effects were negatively correlated with enzyme activities associated with the C recycle, SOC, and total nitrogen (TN) contents (P<0.01). NT increased enzyme activities, SOC, and TN contents and thus reduced priming effects and improved residual C. Synthesis and applications. These results suggested that wheat may contribute more to SOC accumulation than maize, and carbon increment efficiency in farmland could be enhanced by considering the crucial roles of C3 crops in SOC accumulation. NT practice sustains the benefits of C3 crops to SOC sequestration in the upper soil depths.

opencc-zeroOct 2022View details →

Effects of land clearing for agriculture on soil organic carbon stocks in drylands: A meta-analysis

To improve our understanding of clearing natural ecosystems for cropland on soil organic carbon stocks in drylands, we searched for related peer-reviewed research papers published from 1980 to 2022 on the Web of Science (<a href="https://www.webofscience.com">https://www.webofscience.com</a>) and the Scopus Database (<a href="https://www.scopus.com">https://www.scopus.com</a>) (accessed on 30th April 2022). Then, we screened papers for integrity, relevance, and scientific merit under the following criteria: (1) We made sure all studies were independent and based on field-measured data; (2) Each study had to report paired SOC stocks of cropland and adjacent natural ecosystems with the same or a similar suite of environmental factors; (3) Studies need to explicitly present results on SOC stocks or concentrations for certain depths and areas; (4) Studies have specified the types of natural ecosystems that were converted to cropland, which are used as criteria for defining CNEC types. Finally, we winnowed results to a total of 159 scientific journal articles, comprising 242 sites with 1379 paired soil layer observations from 601 paired soil profiles.

opencc-by-4.0Apr 2024View details →

Global soil organic carbon in tidal marshes version 1

[Please note: The current version is incorrect as the prediction values are maxed out to 256 due to a data formatting error when preparing the tiles for the Zenodo upload. We apologize for the inconvenience, and are in the process of preparing a new upload of the data.] This dataset is the first version of the predictions, expected model error, and area of applicability of the global soil organic carbon in tidal marshes at a 30 m resolution. All methods are provided in detail in the accompanying Nature Communications paper, <a href="https://doi.org/10.1038/s41467-024-54572-9">Maxwell et al. (2024)</a> Soil carbon in the world's tidal marshes. Tidal marsh extent map <ul> <li><a href="https://doi.org/10.1101/2023.05.26.542433">Worthington et al. (2023)</a> The distribution of global tidal marshes from earth observation data. bioRxiv. </li> </ul> Training data <ul> <li><a href="https://doi.org/10.1038/s41597-023-02633-x">Maxwell et al. (2023)</a> Global dataset of soil organic carbon in tidal marshes. Scientific Data.</li> <li><a href="https://doi.org/10.1111/gcb.17098">Holmquist et al. (2024)</a> The Coastal Carbon Library and Atlas: Open source soil data and tools supporting blue carbon research and policy. Global Change Biology. </li> <li>Citations for the training data from the above-mentioned syntheses are available <a href="https://github.com/Tania-Maxwell/global-marshC-map/blob/main/reports/02_data_process/data/map_training_data.bib">here</a>.</li> </ul> Model  <ul> <li>Code available on <a href="https://github.com/Tania-Maxwell/global-marshC-map/tree/main">Github</a>.</li> <li>3D soil modelling approach: <a href="https://soilmapper.org/">Hengl & MacMillan (2019)</a>. Predictive Soil Mapping with R.</li> <li>Random forest model: <a href="https://doi.org/10.18637/jss.v028.i05">Kuhn (2008)</a>. Building Predictive Models in R Using the caret Package. J. Stat. Softw. </li> <li>k-NNDM spatial cross validation: <a href="https://hannameyer.github.io/CAST/">Meyer, Milà & Ludwig (2022)</a>. CAST: ‘caret’ Applications for Spatial-Temporal Models. </li> <li>Area of applicability: <a href="https://doi.org/10.1038/s41467-022-29838-9">Meyer & Pebesma (2022)</a>. Machine learning-based global maps of ecological variables and the challenge of assessing them. Nature Communications.</li> </ul> <h2>Description of files</h2> <ul> <li>GRID.zip: shapefile with the location of each tile in the zipped folders below </li> <li>Final_predicted_SOC_both_layers.png: final predicted tidal marsh soil organic carbon (SOC) for a) the 0-30 cm soil layer and b) the 30-100 cm soil layer (aggregated per 2° cell). </li> </ul> Area of applicability  <ul> <li>aoa0.zip: the area of applicability (AOA) mask for the 0-30 cm layer. Pixels with an AOA value of 0 or 0.5 are considered outside the AOA; with an AOA value of 1 are considered inside the AOA.</li> <li>aoa30.zip: the area of applicability (AOA) mask for the 30-100 cm layer. Pixels with an AOA value of 0 or 0.5 are considered outside the AOA; with an AOA value of 1 are considered inside the AOA.</li> </ul> Final predictions and expected error  <ul> <li>pred0_aoa.zip: predicted soil organic carbon for the 0-30 cm layer (Mg C ha-1), masked by the area of applicability.</li> <li>pred30_aoa.zip: predicted soil organic carbon for the 30-100 cm layer (Mg C ha-1), masked by the area of applicability.</li> <li>err0_aoa.zip: expected model error for the 0-30 cm layer (Mg C ha-1), masked by the area of applicability. </li> <li>err30_aoa.zip: expected model error for the 30-100 cm layer (Mg C ha-1), masked by the area of applicability. </li> </ul> Initial predictions and expected error <ul> <li>pred0.zip: predicted soil organic carbon for the 0-30 cm layer (Mg C ha-1).</li> <li>pred30.zip: predicted soil organic carbon for the 30-100 cm layer (Mg C ha-1).</li> <li>err0.zip: expected model error for the 0-30 cm layer for all tidal marsh extent pixels (Mg C ha-1).</li> <li>err30.zip: expected model error for the 30-100 cm layer for all tidal marsh extent pixels (Mg C ha-1).</li> </ul>

Contrasting Responses of Particulate and Mineral-Associated Organic Carbon to Afforestation Potentially Obscure Soil Carbon Accumulation [Dataset]

This is the data repository for the manuscript “Contrasting Responses of Particulate and Mineral-Associated Organic Carbon to Afforestation Potentially Obscure Soil Carbon Accumulation” submitted to Global Biogeochemical Cycles.

Dataset for the Global Prediction Of Total Organic Carbon In Marine Sediments Using Deep Neural Networks (nn-toc)

The data folder contains the raw features and labels used for training machine learning models to predict total organic carbon in marine sediments.  The data folder has three subfolders: <ol> <li>raw : contains the labels, features and other data used to train the machine learnign models</li> <li>interim : transformed data, which has to be reproduced</li> <li>output : output from the models, used for analysis and visualisation</li> </ol> The data folder has to be integrated in the Git repository nn-toc, to execute the code.

Data: Water quality and the biodegradability of dissolved organic carbon in drained boreal peatland under different forest harvesting intensities

This repository consists of three files, which contain ground water and ditch water quality data in drained forested peatlands and dissolved organic carbon biodegradation to carbon dioxide. Experiments and results are presented in: Palviainen M., Peltomaa E., Laurén A., Kinnunen N., Ojala A., Berninger F., Zhu X., Pumpanen J. 2022. Water quality and the biodegradability of dissolved organic carbon in drained boreal peatland under different forest harvesting intensities. Science of the Total Environment 806: 150919 <a href="https://doi.org/10.1016/j.scitotenv.2021.150919">https://doi.org/10.1016/j.scitotenv.2021.150919</a>.

opencc-zeroMay 2024View details →

Data from: Warming reduces priming effect of soil organic carbon decomposition along a subtropical elevation gradient

The priming effects (PEs) of soil organic carbon (SOC) is a crucial process affecting the C balance of terrestrial ecosystems. However, there is uncertainty about how PEs will respond to climate warming. Here, we sampled soils along a subtropical elevation gradient in China and conducted a 126-day lab-incubation experiment with and without additions of 13C-labeled high-bioavailability glucose or low-bioavailability lignin. Based on the mean annual temperature (MAT) of each elevation (9.3–16.4°C), a temperature increase of 4°C was used to explore how PEs mediate the decomposition of SOC in response to warming. Our results showed that the magnitude of glucose-induced PEs (PEglu) was higher than lignin-induced PEs (PElig), with both PEs linearly increasing with MAT. Across the MAT (i.e., elevation) gradient, warming had consistent negative effects on PEglu, whereas rising MAT exacerbated the negative effects of warming on PElig. Moreover, the temperature sensitivity of SOC decomposition decreased after adding glucose and lignin across the MAT gradient, suggesting that fresh C inputs may prime microbial breakdown of labile SOC under warming. Taken together, warming alleviated the SOC loss due to PEs through varying mechanisms depending on substrate bioavailability, since warming mediated the PEglu by increasing available nitrogen and weakening microbial nitrogen-mining but inhibited the PElig by switching from microbial nitrogen-mining to microbial co-metabolization. Our findings highlight the role of warming in regulating the PEs and suggest that incorporating the suppression effect of warming on PEs can contribute to the accurate prediction of soil C dynamics in a warming world.

Supporting material for von Fromm et al (2024) Moisture and soil depth govern relationships between soil organic carbon and oxalate-extractable metals at the global scale

This file contains the supporting material for von Fromm et al (2024) Moisture and soil depth govern relationships between soil organic carbon and oxalate-extractable metals at the global scale (submitted).  For more details see the corresponding manuscript (once it is published) and the github repository (https://github.com/SophievF/Global_Mox_analysis/tree/main).