Find research datasets worth reusing

Plum Island Ecosystems site, station Parker Dam, study of dissolved organic carbon in streamwater in units of milligramsPerLiter on a yearly timescale

The EcoTrends project was established in 2004 by Dr. Debra Peters (Jornada Basin LTER, USDA-ARS Jornada Experimental Range) and Dr. Ariel Lugo (Luquillo LTER, USDA-FS Luquillo Experimental Forest) to support the collection and analysis of long-term ecological datasets. The project is a large synthesis effort focused on improving the accessibility and use of long-term data. At present, there are ~50 state and federally funded research sites that are participating and contributing to the EcoTrends project, including all 26 Long-Term Ecological Research (LTER) sites and sites funded by the USDA Agriculture Research Service (ARS), USDA Forest Service, US Department of Energy, US Geological Survey (USGS) and numerous universities. Data from the EcoTrends project are available through an exploratory web portal (http://www.ecotrends.info). This web portal enables the continuation of data compilation and accessibility by users through an interactive web application. Ongoing data compilation is updated through both manual and automatic processing as part of the LTER Provenance Aware Synthesis Tracking Architecture (PASTA). The web portal is a collaboration between the Jornada LTER and the LTER Network Office. The following dataset from Plum Island Ecosystems (PIE) contains dissolved organic carbon in streamwater measurements in milligramsPerLiter units and were aggregated to a yearly timescale.

Walker Branch Watershed site, station West Fork of Walker Branch Watershed, study of dissolved organic carbon in streamwater in units of milligramsPerLiter on a yearly timescale

The EcoTrends project was established in 2004 by Dr. Debra Peters (Jornada Basin LTER, USDA-ARS Jornada Experimental Range) and Dr. Ariel Lugo (Luquillo LTER, USDA-FS Luquillo Experimental Forest) to support the collection and analysis of long-term ecological datasets. The project is a large synthesis effort focused on improving the accessibility and use of long-term data. At present, there are ~50 state and federally funded research sites that are participating and contributing to the EcoTrends project, including all 26 Long-Term Ecological Research (LTER) sites and sites funded by the USDA Agriculture Research Service (ARS), USDA Forest Service, US Department of Energy, US Geological Survey (USGS) and numerous universities. Data from the EcoTrends project are available through an exploratory web portal (http://www.ecotrends.info). This web portal enables the continuation of data compilation and accessibility by users through an interactive web application. Ongoing data compilation is updated through both manual and automatic processing as part of the LTER Provenance Aware Synthesis Tracking Architecture (PASTA). The web portal is a collaboration between the Jornada LTER and the LTER Network Office. The following dataset from Walker Branch Watershed (WBW) contains dissolved organic carbon in streamwater measurements in milligramsPerLiter units and were aggregated to a yearly timescale.

Florida Coastal Everglades site, station Taylor Slough/Panhandle Site 6a, study of dissolved organic carbon in coastal water in units of microMolesPerLiter on a yearly timescale

The EcoTrends project was established in 2004 by Dr. Debra Peters (Jornada Basin LTER, USDA-ARS Jornada Experimental Range) and Dr. Ariel Lugo (Luquillo LTER, USDA-FS Luquillo Experimental Forest) to support the collection and analysis of long-term ecological datasets. The project is a large synthesis effort focused on improving the accessibility and use of long-term data. At present, there are ~50 state and federally funded research sites that are participating and contributing to the EcoTrends project, including all 26 Long-Term Ecological Research (LTER) sites and sites funded by the USDA Agriculture Research Service (ARS), USDA Forest Service, US Department of Energy, US Geological Survey (USGS) and numerous universities. Data from the EcoTrends project are available through an exploratory web portal (http://www.ecotrends.info). This web portal enables the continuation of data compilation and accessibility by users through an interactive web application. Ongoing data compilation is updated through both manual and automatic processing as part of the LTER Provenance Aware Synthesis Tracking Architecture (PASTA). The web portal is a collaboration between the Jornada LTER and the LTER Network Office. The following dataset from Florida Coastal Everglades (FCE) contains dissolved organic carbon in coastal water measurements in microMolesPerLiter units and were aggregated to a yearly timescale.

Central Arizona - Phoenix Urban LTER site, station Lost Dutchman State Park Depostion Site, study of dissolved organic carbon in wet deposition in units of kilogramsPerHectare on a yearly timescale

The EcoTrends project was established in 2004 by Dr. Debra Peters (Jornada Basin LTER, USDA-ARS Jornada Experimental Range) and Dr. Ariel Lugo (Luquillo LTER, USDA-FS Luquillo Experimental Forest) to support the collection and analysis of long-term ecological datasets. The project is a large synthesis effort focused on improving the accessibility and use of long-term data. At present, there are ~50 state and federally funded research sites that are participating and contributing to the EcoTrends project, including all 26 Long-Term Ecological Research (LTER) sites and sites funded by the USDA Agriculture Research Service (ARS), USDA Forest Service, US Department of Energy, US Geological Survey (USGS) and numerous universities. Data from the EcoTrends project are available through an exploratory web portal (http://www.ecotrends.info). This web portal enables the continuation of data compilation and accessibility by users through an interactive web application. Ongoing data compilation is updated through both manual and automatic processing as part of the LTER Provenance Aware Synthesis Tracking Architecture (PASTA). The web portal is a collaboration between the Jornada LTER and the LTER Network Office. The following dataset from Central Arizona - Phoenix Urban LTER (CAP) contains dissolved organic carbon in wet deposition measurements in kilogramsPerHectare units and were aggregated to a yearly timescale.

openOpenFeb 2016View details →

Dissolved organic carbon (DOC) measurements from Toolik Lake Inlet and Toolik Lake main, Toolik Field Sation, North Slope Alaska for 2005-2008.

Dissolved organic carbon (DOC) measurements from Toolik Lake Inlet and Toolik Lake main sampling station for 2005-2008. The earliest measurements were in May and with the latest in September.

Dissolved organic carbon dynamics in an urban desert stream ecosystem in central Arizona-Phoenix

Variation in stream chemistry is a function of the strength of terrestrial-aquatic linkages, the extent to which surface and groundwater exchanges, and the rate of instream biotic processes. The importance of these variables may fluctuate as a function of climate regime, catchment geomorphology, or level of human impact. A mechanistic understanding of the influence of each of these variables on ecosystem functioning will increase understanding of the role of streams in global nutrient and carbon cycles. Of particular interest is dissolved organic carbon (DOC), an important source of carbon and energy for microbial processes. Respiration by heterotrophic bacterial communities has recently been linked to the quality (ability of microbes to utilize C source) of the DOC pool in streams. DOC not only influences stream nutrient supply, but also the transport of contaminants and the attenuation of UV radiation. This dissertation focused on DOC delivery to two arid-land stream ecosystems, one native desert (Sycamore Creek, AZ), and one urban (Phoenix, AZ). The overall objectives of this work were to (1) document patterns in DOC quantity and chemical composition in response to flooding and groundwater exchange, (2) generate and test hypotheses explaining variation in DOC quantity and quality and (3) relate this variation to microbial activity. In the native desert stream ecosystem, the climate regime influenced seasonal variation in the quantity and quality of DOC inputs, with higher complexity and higher concentrations of DOC in summer monsoonal runoff. In contrast, human alteration of geomorphology and hydrologic flowpaths in the Phoenix metropolitan area significantly influenced streamwater chemistry in comparison to low-impact streams in the Sonoran Desert. In the city, mechanisms of nutrient retention and transformation were often shifted from dominance by biotic to abiotic ones, severely dampening the influence of climate regime and substituting instead the maintenance

openCC (other)Nov 2018View details →

Vegetation cover and Soil Organic Carbon along gradients of cattle grazing intensity in the Jornada Basin, July-August 2016

The goal of this Master’s thesis project, which was carried out in July and August of 2016, was to assess the effect of inferred grazing intensity on 1) vegetation cover type and 2) soil organic carbon (SOC) at the Jornada Experimental Range in southern New Mexico. A sampling transect was established at each of 3 long term cattle water sources (85-106 years old), beginning 5m from the water source and continuing 1500m outward. Soil bulk density, soil organic carbon, soil organic nitrogen, and dominant plant cover type (shrub, grass, and bare soil) were sampled at 20 locations on each transect. Two hypotheses evaluated in this study are: 1) higher grazing pressure near the water source will lead to reduced vegetation cover and C inputs into the soil, leading to higher SOC stocks in soil with far proximity to the water source; and 2) Grazing very close to the water source will exert high disturbance and deposit SOC via defecation, leading to higher SOC stocks in soil with close proximity to the water source.

opencc-by-4.0Mar 2020View details →

Time-series rates of dissolved organic carbon production in the subtropical North Pacific Ocean

Over a 3-year period (April 2010-April 2013), we measured 14C-DOC production from vertical profiles used for determination of 14C-particle production, utilizing 0.2 um filtrates. Seawater for these experiments was collected from predawn CTD hydrocasts into acid-cleaned 500-ml polycarbonate bottles. A total of four replicate 500 ml bottles were subsampled per depth and each bottle was spiked with ~1.85 MBq 14C-bicarbonate. One hundred milliliters from one replicate per depth was vacuum filtered through a 0.2 mm polycarbonate filter and the filtrate served as a time zero blank. The remaining three bottles were hung on a free-drifting array, deployed before dawn, and incubated at their initial collection depths throughout the photoperiod (typically 11-13 hours). After sunset the array was recovered, and 100 ml subsamples of all bottles were filtered under gentle vacuum (<50 mm Hg) onto 0.2 mm polycarbonate filters. These 0.2 mm filtrates were stored frozen (-20oC) until subsequent processing for determination of 14C-DOC productivity. Samples were processed as follows: 100 ml of the 14C-PC filtrates were thawed, poured into 500 ml polyethylene separatory funnels, and acidified by the addition of 500 µl of 2 M sulfuric acid (H2SO4). Samples were vigorously bubbled with air in a fume hood to remove 14CO2. A 70 ml subsample was removed from each separatory funnel and poured into a 100 ml glass serum bottle containing 1 ml of 2 M sodium hydroxide (NaOH) and 10 ml of 0.37 M potassium persulfate (K2S2O8) in 1 M NaOH. Bottles were sealed with rubber stoppers, crimp sealed with an aluminum cap, and autoclaved at 126°C for 200 minutes; oxidizing 14C-DOC to 14C-DIC in an alkaline solution. Once cooled to room temperature, samples were uncapped and resealed using rubber sleeve stoppers holding plastic center wells containing ~2 x 2 cm pieces of fluted chromatographic filter paper (Whatman 2) soaked with 0.2 ml of β-phenylethylamine. A syringe was used to inject 4 ml of 9 N H2SO4 into the solution, converting the 14C-labeled dissolved inorganic carbon (hereafter 14C-DIC) to 14CO2. Samples were stored undisturbed at room temperature, passively trapping the 14CO2 on the β-phenylethylamine soaked wick. After at least 100 hours, rubber sleeve stoppers were removed and center wells and wicks were placed in scintillation vials, followed by the addition of 10 ml of Ultima Gold LLT scintillation cocktail. Samples were subsequently counted on a Perkin Elmer Tri-Carb 2800TR liquid scintillation counter. Rates of 14C-DOC production were computed for each cruise as the mean of the triplicate bottles from each depth minus the average 14C-activity of the time zero (blank) samples.

opencc-by-4.0May 2020View details →

Reservoir constructions reduced half the organic carbon burial in the East China Sea

Data Set S1.  Supplementary Data-OC properties Data Set S2.  Supplementary Data-Surface sediment grain size

opencc-zeroAug 2020View details →

Soil organic carbon accumulation modes between pioneer and old-growth forest ecosystems

1. Increasing evidence suggests that high biomass and litterfall do not necessarily bring about soil organic carbon (SOC) sinks, contrary to the assumption that higher litterfall implies higher SOC when designing carbon models. The underlying mechanism is related to the quality of litter. 2. We conducted 15 years (2000–2015) of consecutive field measurements of δ13C values in SOC and plants in a pioneer forest (Pinus massoniana forest, PF) and an old-growth forest (monsoon evergreen broadleaved forest, BF), using an isotope mixing model based on mass balance to quantify the effects of vegetation on SOC stock and soil characteristics. 3. The carbon to nitrogen (C/N) ratio of litter in BF was lower than that in PF. The proportion of organic carbon yield input to the soil (Cinput) to the total litter carbon loss during decomposition was 38.7 ± 3.3% and 28.0 ± 2.1% in BF and PF, respectively. New carbon input was higher in BF (148.7 ± 8.8 g C m−2 yr−1) than PF (99.7 ± 4.5 g C m−2 yr−1), though there was a non-significant difference in annual litterfall between the two forests. Moreover, the Cinput was concentrated in the topsoil layer in PF but distributed in a more dispersed state across the whole soil profile in BF. Consequently, only the δ13C values of SOC decreased in the topsoil layer of PF, whereas these decreased at both soil depths in BF from 2000 to 2015. 4. Compared with PF, BF exhibited higher carbon input and a more favourable soil environment for carbon storage. It was the amount of intermediate product (i.e., Cinput) of litter decomposition, not the amount of litterfall itself, that drove the contrasting differences in SOC status. 5. Synthesis and applications. Litter quality controls SOC accumulation by regulating the fate of decomposing litter, which may explain why old-growth forests can sustainably accumulate carbon in soil. This finding questions the carbon models that predict the dependence of SOC accumulation on biomass and litter yield and suggests that litter quality should be valued in future carbon cycling models.30-Jul-2020

opencc-zeroOct 2020View details →

The dynamics and stoichiometry of dissolved organic carbon release by kelp: Carbon fixation, DOC release and nutrient uptake data

Canopy-forming kelps are foundational species in coastal ecosystems, fixing tremendous amounts of carbon, yet we know little about the ecological and physiological determinants of dissolved organic carbon (DOC) release by kelps. We examined DOC release by the bull kelp, Nereocystis luetkeana, in relation to carbon fixation, nutrient uptake, tissue nitrogen content, and light availability. DOC release was approximately 3.5 times greater during the day than at night. During the day, N. luetkeana blades released an average of 16.2% of fixed carbon as DOC. Carbon fixation increased with light availability but DOC release did not, leading to a lower proportion of fixed carbon released as DOC at high light levels. We found no relationship between carbon fixation and DOC release rates measured concurrently. Rather, DOC release by N. luetkeana blades declined with marginal significance as blade tissue nitrogen content increased and with experimental nitrate addition, supporting the role of stoichiometric relationships in DOC release. Using a stable isotope (13C) tracer method, we demonstrated that inorganic carbon is rapidly fixed and released by N. luetkeana blades as 13DOC, within hours. However, recently fixed carbon (13DOC) comprised less than 20% of the total DOC released, indicating that isotope studies that rely on tracer production alone may underestimate total DOC release, as it is decoupled from recent kelp productivity. Comparing carbon and nitrogen assimilation dynamics of the annual kelp N. luetkeana with the perennial kelp Macrocystis pyrifera revealed that N. luetkeana had significantly higher carbon fixation, DOC production and nitrogen uptake rates per unit dry mass. Both kelp species were able to perform light-independent carbon fixation at night. Carbon fixation by the annual kelp N. luetkeana is as high as 2.35 kg C m-2 yr-1, but an average of 16% of this carbon (376 g C m-2 yr-1) is released as DOC. As kelp forests are increasingly viewed as vehicles for carbon sequestration, it is important to consider the fate of this substantial quantity of DOC released by canopy-forming kelps.

opencc-by-4.0Sep 2019View details →

Detailed global modelling of soil organic carbon in cropland, grassland and forest soils

Supporting information of the paper: Morais, T.G., Teixeira, R.F.M., Domingos, T. 2019. Detailed global modelling of soil organic carbon in cropland, grassland and forest soils. PloS One. Version 2 includes raster files (.tif) for each land use class (including: Attainable SOC stock, mineralization rate, and fator K).

opencc-by-4.0Nov 2020View details →

Soil organic carbon distribution for 0-3 m soils at 1 km2 scale of the frozen ground in the Third Pole Regions

Soil organic carbon (SOC) is very important in the vulnerable ecological environment of the Third Pole; however, data regarding the spatial distribution of SOC are still scarce and uncertain. Based on multiple environmental variables and soil profile data from 458 pits (depth of 0–1 m) and 114 cores (depth of 0–3 m), this study uses a machine-learning approach to evaluate the SOC storage and spatial distribution at different soil depths (0–30 cm, 0–50 cm, 0–100 cm, 0–200 cm, and 0–300 cm) in the frozen ground area of the Third Pole region. Our results provide information on the storage, patterns, and environmental controls of SOCSs at a 1 km2 scale for areas of frozen ground in the Third Pole region, thus providing a scientific basis for future studies pertaining to Earth system models. Soil organic carbon data is stored in grids format, and the file name is "TP-SOC-d.tif", where d represents soil depth, for example, "TP-SOC-30.tif" represents the spatial distribution of soil organic carbon stocks in the Third Pole regions of the upper 30 cm depth interval.

opencc-zeroApr 2020View details →

Soil organic carbon in drylands: shrub encroachment and vegetation management effects dwarf those of livestock grazing

Dryland ecosystems occur worldwide and play a prominent, but potentially shifting, role in global biogeochemical cycling. Widespread woody plant proliferation, often associated with declines in palatable grasses, has jeopardized livestock production in drylands and prompted attempts to reduce woody cover by chemical or mechanical means. Woody encroachment also has the potential to significantly alter terrestrial carbon storage. However, little is known of the long-term biogeochemical consequences of woody encroachment in the broader context of its interaction with common dryland land uses, including "brush management" (woody plant clearing) and livestock grazing. Present assessments exhibit considerable variation in the consequences of these land use/land cover changes, with evidence that brush management may counteract sizeable impacts of shrub encroachment on soil biogeochemical pools. A challenge to assessing the net effects of brush management in shrub-encroached grasslands on soil organic carbon (SOC) and total nitrogen (N) pools is that land management practices are typically considered in isolation, when they are co-occurring phenomena. Furthermore, few studies have assessed spatial patterns in brush management and how these are affected in decades following treatment on sites with contrasting grazing histories. To address these uncertainties and interactions, we quantified the impacts of shrub encroachment and their subsequent mortality resulting from brush management (herbicide application) on SOC and N pools in a Sonoran Desert grassland where long-term grazing manipulations (>100 y) co-occur with shrub encroachment and brush management. Pools of SOC and N associated with herbicided shrubs declined markedly over ~40 years, offsetting 66% of the increases from shrub encroachment. However, spatial patterns in SOC induced by shrubs persisted over the decades following brush management. Century-long protection from grazing did little to change SOC and N pools. Accordingly, shrub encroachment and shrub mortality from brush management each far outweighed livestock grazing impacts. Consideration of the patterns of SOC and N through space (e.g., bole-to-dripline gradients), time (e.g., shrub age/size), land use (e.g., livestock grazing and brush management) and their interactions will position us to improve predictions of SOC and N responses to land use/land cover change, inform C-based management decisions, and objectively evaluate trade-offs with other ecosystem services.

opencc-zeroDec 2016View details →

Data from: Mangrove outwelling is a significant source of oceanic exchangeable organic carbon

Exchangeable dissolved organic carbon (EDOC) makes up a significant proportion of the oceanic dissolved organic carbon (DOC) pool, yet EDOC sources to the coastal ocean are poorly constrained. We measured the exchange of EDOC and concentrations of EDOC and DOC in mangrove waters over a 26° latitudinal gradient. A clear latitudinal trend was observed, with the highest EDOC concentrations in the tropics. EDOC exports to the coastal ocean were 4.7 ± 1.9 mmol m−2 d−1, equivalent to 11% of DOC exports (42.1 ± 6.7 mmol m−2 d−1). Pore-water and groundwater exchange were minor sources of EDOC. EDOC concentrations were equal to 13% ± 4% of DOC concentrations. Based on previous global DOC export estimates, and our EDOC : DOC ratios, mangroves outwell 3.1 Tg C yr−1 as EDOC, equivalent to ∼ 60% of the global EDOC flux from the ocean to the atmosphere. However, seasonality of mangrove EDOC cycling requires further research.

opencc-by-4.0Oct 2024View details →

Abrupt loss of soil organic carbon following disturbance in seagrass ecosystems

<h1>Code for running the bifurcation diagrams and the sensitivity analysis of seagrass-soil model</h1>   Contact: antoine.levilain18@gmail.com   This repository contains the code used to conduct the figures of: Abrupt loss of soil organic carbon following disturbance in seagrass ecosystems. Each figure from the related study has its own folder, which includes the necessary scripts to rerun simulations, the output of those simulations, and the code to plot the results. By navigating to any figure’s folder, you can reproduce the simulations and visualise the results. The repository is organised to facilitate reproducibility and further exploration of the ecosystem model and its behavior under various scenarios. We performed our analysis using R version 3.6.3. Do not forget to add your working directory if you want to save the figures.   <h2>Sensitivity analysis (Figure 5, Figure S11, Figure S15 & Figure S16)</h2> The “sensitivity” folder contains subfolders with the scripts required to run the global sensitivity analysis using the Sobol method for each scenario/case, along with the resulting outputs. In this analysis, higher numbers in folder names indicate a more deteriorated meadow, meaning it’s closer to the point of collapse. The analysis was conducted across different scenarios for different cases: “f” denotes the feedback case, while “no_f” represents the no feedback case. To recreate the figures, you can plot the pie charts for each scenario/case by running the sensitivity_plot.R script after setting the working directory to the appropriate subfolder.

opencc-by-4.0Oct 2024View details →

Soil dissolved organic carbon (DOC) machine learning model code

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opencc-by-4.0Jul 2024View details →

Long-term climate trends and urbanization reveal human impacts and decoupling of dissolved organic carbon quantity and composition in streams

This repository contains data, R code, graphical objects, and outputs in Kelley et al. (2025) entitled Climate Change and Urbanization Decouple Dissolved Organic Carbon Quantity and Composition in Streams accepted for publication in Global Biogeochemical Cycles. <a href="https://doi.org/10.1029/2025GB008534">https://doi.org/10.1029/2025GB008534</a> In this finalized repository, we provide a detailed meta data file (1_repository_meta_data.xlsx) containing lists and descriptions of all data files, variables, figures, and scripts within. Note that previous versions contained water quality parameters for forms of nitrogen and phosphorus, which have been removed from this final version. These parameters were neither used in any analyses in this work nor underwent QA/QC protocols; thus, we suggest caution in their use from previous versions. Additionally, this repository contains a publication license for a graphical object created using the BioRender platform.

opencc-by-4.0Nov 2023View details →

Particulate and mineral-associated organic carbon storage

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