Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
152
datasets available to search
ShareScore release 0.7.1
Dataset results
152 results for “lake sediment”
Absolute time markers and age-depth model for the last 75 kyr of Lake Chala sediments
<p>The 171 time markers include 162 <sup>14</sup>C ages on bulk organic matter or grass charcoal in sediment intervals of the composite Challacea (CH03, CH05) sequence (Blaauw et al., 2011), transferred to the DeepCHALLA (DCH) composite sequence using mm- or cm-scale cross-correlation of visual lithostratigraphy (Baxter et al., 2023). The other nine time markers are six <sup>210</sup>Pb-dated intervals from gravity core CH99-1G transferred to the CH05 and DCH sequences using 1-cm resolution magnetic-susceptibility profiles (Blaauw et al., 2011), the November 2016 (DCH) and March 2005 (CH05) sediment-water interfaces, and the YTT cryptotephra (Baxter et al., 2023). Lab codes stand for the Poznan Radiocarbon Laboratory (Poz-), the Chrono Centre at Queen’s University in Belfast (UBA-), the Isotope Physics Laboratory at the University of Groningen (GrA-), the Saint-Croix Watershed Research Station of the Science Museum of Minnesota (SMM), and the Cambridge Tephra Laboratory (CT-). ‘Offset’ refers to the old-carbon age offset of bulk organic <sup>14</sup>C dates, modelled using 16 paired dates on bulk organic matter and grass charcoal and three sections allowing <sup>14</sup>C wiggle-match dating using closely spaced bulk organic samples (Blaauw et al., 2011). The compound error on corrected <sup>14</sup>C ages was calculated as SQRT ((Age Error)^2 + (Offset STD)^2). All dated intervals are represented by their DCH event-free depth in meter (mefd). </p>
A modern pollen dataset from lake surface sediments on the central-western Tibetan Plateau
<p>This is a modern pollen dataset on the central and western Tibetan Plateaubased on lake surface sediments of 90 lakes. The dataset includes pollen counts and pollen percentages for each lake sediment sample together with their locations (latitude, longitude and altitude) and climatic data. </p>
Data for: Water depth and transparency drive the quantity and quality of organic matter in sediments of Alpine lakes on the Tibetan Plateau
<p>The primary objectives of the study were to: (i) determine OM quantity and quality in the sediments of alpine lakes on the Tibetan Plateau, (ii) identify the primary environmental regulators of OM quantity and quality, and (iii) reveal OM transformations in the water column and sediments.</p> <p>Firstly, we collected sediments and lake water from 20 lakes with diverse morphology and sizes across the entire Tibetan Plateau.</p> <p>Secondly, We analyzed the bulk sedimentary OM and two leachable pools of the sedimentary OM, i.e., water-soluble OM and alkaline-extracted OM combining elemental and stable isotopic analysis, optical measurements (i.e., absorbance and fluorescence spectroscopy), and ultrahigh-resolution molecular techniques (i.e., electrospray ionization-assisted Fourier transform-ion cyclotron resonance mass spectrometry, ESI FT-ICR MS). We also measured the lake water physicochemical characteristics (i.e., depth, transparency, salinity, turbidity, DO, pH, TN, TP and Chl a), as well as the composition of dissolved OM in water column via optical measurements.</p> <p>Thirdly, we performed statistical analysis to determine the primary environmental control and predictors of the spatial variability in sedimentary OM on the Tibetan Plateau. The statistical analysis included non-parametric Kruskal-Wallis with Dunn post hoc test, redundancy analysis, and linear regression models.</p> <p>Main results of the study are that (i) sedimentary water-soluble OM and alkaline-extracted OM were both dominated by low-molecular-weight, low-aromaticity compounds with low contributions of terrestrial humic substances, suggesting that sedimentary leachable OM was primarily regulated by in-lake sources and processes; (ii) water depth, water transparency, and total phosphorus concentration in water column explained ~50% variance of sedimentary bulk and leachable OM, substantiating the importance of autochthonous sources and primary productivity in regulating the quantity and quality of sedimentary OM; (iii) in comparison to lake surface water DOM, water-soluble OM and alkaline-extracted OM from sediments had higher proportions of terrestrial humic-like substances, suggesting preferential preservation of allochthonous materials in the sediments.</p>
Soil-biodegradable plastic films do not decompose in a lake sediment over 9 months of incubation
<p>Dataset with the article 'Soil-biodegradable plastic films do not decompose in a lake sediment over 9 months of incubation', containing CO2 and CH4 data of sediment core incubations in a laboratory setting.</p> <p>Time is in days.</p> <p>Group identifiers: PC = control, PE = PE plastics (traditional), PR = Biodegradable plastics type 1, PS = biodegradable plastics type 2.</p>
Denitrification rates in mountain lake sediments
Open the record for dataset details and reuse information.
Data for: Water depth and transparency drive the quantity and quality of organic matter in sediments of Alpine lakes on the Tibetan Plateau
Open the record for dataset details and reuse information.
Data from: Littoral sediment arsenic concentrations predict arsenic trophic transfer and human health risk in contaminated lakes
Open the record for dataset details and reuse information.
Sedimentation inhibits macroalgal priming on an emergent plant decomposition in the littoral zone of an eutrophic lake, China
<p>The data presented in this manuscript (MS# 2020JG005630) are original and are available in zondo.</p>
Next-generation sequencing of DNA from resting eggs: signatures of eutrophication in a lake's sediment
<p>Supplementary data</p>
Data from: Reconstructing long-term human impacts on plant communities: an ecological approach based on lake sediment DNA
Paleoenvironmental studies are essential to understand biodiversity changes over long timescales and to assess the relative importance of anthropogenic and environmental factors. Sedimentary ancient DNA (sedaDNA) is an emerging tool in the field of paleoecology and has proven to be a complementary approach to the use of pollen and macroremains for investigating past community changes. SedaDNA-based reconstructions of ancient environments often rely on indicator taxa or expert knowledge, but quantitative ecological analyses might provide more objective information. Here, we analysed sedaDNA to investigate plant community trajectories in the catchment of a high-elevation lake in the Alps over the last 6400 years. We combined data on past and present plant species assemblages along with sedimentological and geochemical records to assess the relative impact of human activities through pastoralism, and abiotic factors (temperature and soil evolution). Over the last 6400 years, we identified significant variation in plant communities, mostly related to soil evolution and pastoral activities. An abrupt vegetational change corresponding to the establishment of an agropastoral landscape was detected during the Late Holocene, approximately 4500 years ago, with the replacement of mountain forests and tall-herb communities by heathlands and grazed lands. Our results highlight the importance of anthropogenic activities in mountain areas for the long-term evolution of local plant assemblages. SedaDNA data, associated with other paleoenvironmental proxies and present plant assemblages, appear to be a relevant tool for reconstruction of plant cover history. Their integration, in conjunction with classical tools, offers interesting perspectives for a better understanding of long-term ecosystem dynamics under the influence of human-induced and environmental drivers.
Data from: Molecular profiling of diatom assemblages in tropical lake sediments using taxon-specific PCR and Denaturing High-Performance Liquid Chromatography (PCR-DHPLC)
Here we present a protocol to genetically detect diatoms in sediments of the Kenyan tropical Lake Naivasha, based on taxon-specific PCR amplification of short fragments (approx. 100 bp) of the small subunit ribosomal (SSU) gene and subsequent separation of species-specific PCR products by PCR-based DHPLC. An evaluation of amplicons differing in primer specificity to diatoms and length of the fragments amplified demonstrated that the number of different diatom sequence types detected after cloning of the PCR products critically depended on the specificity of the primers to diatoms and the length of the amplified fragments whereby shorter fragments yielded more species of diatoms. The DHPLC was able to discriminate between very short amplicons based on the sequence difference, even if the fragments were of identical length. and if the amplicons differed only in a small number of nucleotides. Generally the method identified the dominant sequence types from mixed amplifications. A comparison with microscopic analysis of the sediment samples revealed that the sequence types identified in the molecular assessment corresponded well with the most dominant species. In summary, the PCR-based DHPLC protocol offers a fast, reliable, and cost-efficient possibility to study DNA from sediments and other environmental samples with unknown organismic content, even for very short DNA fragments.
Data from: Long livestock farming history and human landscape shaping revealed by lake sediment DNA
The reconstruction of human-driven, Earth-shaping dynamics is important for understanding past human/environment interactions and for helping human societies that currently face global changes. However, it is often challenging to distinguish the effects of the climate from human activities on environmental changes. Here we evaluate an approach based on DNA metabarcoding used on lake sediments to provide the first high-resolution reconstruction of plant cover and livestock farming history since the Neolithic Period. By comparing these data with a previous reconstruction of erosive event frequency, we show that the most intense erosion period was caused by deforestation and overgrazing by sheep and cowherds during the Late Iron Age and Roman Period. Tracking plants and domestic mammals using lake sediment DNA (lake sedDNA) is a new, promising method for tracing past human practices, and it provides a new outlook of the effects of anthropogenic factors on landscape-scale changes.
Data from: Tracking the history and ecological changes of rising double-crested cormorant populations using pond sediments from islands in eastern Lake Ontario
In the Laurentian Great Lakes region, the double-crested cormorant (Phalacrocorax auritus) has seen a thousand-fold population increase in recent decades. These large colonies of birds now often conflict with socioeconomic interests, particularly due to perceived competition with fisheries and the destruction of terrestrial vegetation in nesting habitats. Here we use dated sediment cores from ponds on islands in eastern Lake Ontario that receive waste inputs from dense colonies of cormorants and ring-billed gulls (Larus delawarensis) to chronicle the population rise of these species and assess their long-term ecological impacts. Modern water chemistry sampling from these sites reveals drastically elevated nutrient and major ion concentrations compared to reference ponds not influenced by waterbirds. Geochemical tracers in dated sediment cores, particularly δ15N and chlorophyll-a concentrations, track waterbird influences over time. Fossil diatom assemblages were dominated by species tolerant of hyper-eutrophic and polluted systems, which is in marked contrast to assemblages in reference sites. In addition to establishing long-term ecological impacts, this multi-proxy paleoecological approach can be used to determine whether islands of concern have been long-term nesting sites or were only recently colonized by cormorant or ring-billed gull populations across the Great Lakes, facilitating informed management decisions about controversial culling programs.
Arctic shrub colonization lagged peak postglacial warmth: Molecular evidence in lake sediment from Arctic Canada
<p>Arctic shrubification is an observable consequence of climate change, already resulting in ecological shifts and global-scale climate feedbacks including changes in land surface albedo and enhanced evapotranspiration. However, the rate at which shrubs can colonize previously glaciated terrain in a warming world is largely unknown. Reconstructions of past vegetation dynamics in conjunction with climate records can provide critical insights into shrubification rates and controls on plant migration, but paleoenvironmental reconstructions based on pollen may be biased by the influx of exotic pollen to tundra settings. Here, we reconstruct past plant communities using sedimentary ancient DNA (<i>sed</i>aDNA), which has a more local source area than pollen. We additionally reconstruct past temperature variability using bacterial cell membrane lipids (brGDGTs) and an aquatic productivity indicator (biogenic silica) to evaluate the relative timing of postglacial ecological and climate changes at a lake on southern Baffin Island, Arctic Canada. The<i> sed</i>aDNA record tightly constrains the colonization of dwarf birch (<i>Betula</i>, a thermophilous shrub) to 5.9 ± 0.1 ka, ~3 ka after local deglaciation as determined by cosmogenic <sup>10</sup>Be moraine dating and >2 ka later than <i>Betula</i> pollen is recorded in nearby lake sediment. We then assess the paleovegetation history within the context of summer temperature and find that paleotemperatures were highest prior to 6.3 ka, followed by cooling in the centuries preceding <i>Betula</i> establishment. Together, these molecular proxies reveal that <i>Betula</i> colonization lagged peak summer temperatures, suggesting that inefficient dispersal, rather than climate, may have limited Arctic shrub migration in this region. In addition, these data suggest that pollen-based climate reconstructions from high latitudes, which rely heavily on the presence and abundance of pollen from thermophilous taxa like <i>Betula</i>, can be compromised by both exotic pollen fluxes and vegetation migration lags.</p>
Data from: Estimating species colonization dates using DNA in lake sediment
1. Detection of DNA in lake sediments holds promise as a tool to study processes like extinction, colonization, adaptation and evolutionary divergence. However, low concentrations make sediment DNA difficult to detect, leading to high false negative rates. Additionally, contamination could potentially lead to high false positive rates. Careful laboratory procedures can reduce false positive and negative rates, but should not be assumed to completely eliminate them. Therefore, methods are needed that identify potential false positive and negative results, and use this information to judge the plausibility of different interpretations of DNA data from natural archives. 2. We developed a Bayesian algorithm to infer the colonization history of a species using records of DNA from lake-sediment cores, explicitly labelling some observations as false positive or false negative. We illustrate the method by analysing DNA of whitefish (Coregonus lavaretus. L) from sediment cores covering the past 10,000 years from two central Swedish lakes. We provide the algorithm as an R-script, and the data from this study as example input files. 3. In one lake, Stora Lögdasjön, where connectivity with the proto-Baltic Sea and the degree of whitefish ecotype differentiation suggested colonization immediately after deglaciation, DNA was indeed successfully recovered and amplified throughout the postglacial sediment. For this lake we found no loss of detection probability over time, but a high false negative rate. In the other lake, Hotagen, where connectivity and ecotype differentiation suggested colonization long after deglaciation, DNA was amplified only in the upper part of the sediment, and colonization was estimated at 2,200 BP based on the assumption that successful amplicons represent whitefish presence. Here the earliest amplification represents a false positive with a posterior probability of 41%, which increases the uncertainty in the estimated time of colonization. 4. Complementing careful laboratory procedures aimed at preventing contamination, our method estimates contamination rates from the data. By combining these results with estimates of false negative rates, our models facilitate unbiased interpretation of data from natural DNA archives.
The response of nitrogen transformation to hydrological regime at sediment-water interface of seasonal lakes in floodplain: Insights from the Three Gorges Dam-Poyang Lake system
<p><span>This study establishes a coupled model integrating hydrodynamics and nitrogen transformation to elucidate the impacts of the hydrological regime of the Yangtze River after the operation of Three Gorges Dam.</span></p>
Dataset of sediment accumulation rate (SAR) for lake (and peat) records in China
<p>Excel spreadsheet containing: Table S1) table of site information, dating method, and all sediment accumulation rate (SAR) data; Table S2) the 1-kyr-bined median and mean ± standard error (SE) for both SARs and stalagmite O18 from 30 ka BP to the present; and 3) reference list for our dataset.</p> <p>This dataset relates to: Zhang, F., Li, S. H., Sun C. P., Li, W. P., Zhao, X., Chen, Z.Y., Nie, T. Y., Chen, Y. S., Li, X. X. <strong>Human impacts overwhelmed hydroclimate control of soil erosion in China 5000 years ago.</strong> Submitted to <strong><em>Geophysical Research Letters</em></strong></p>
Does salinization impact long-term Daphnia assemblage dynamics? Evidence from the sediment egg bank in a small hard-water lake
<p>Salinization of freshwater ecosystems threatens global aquatic biodiversity. There is a need for studies that follow populations <i>in situ </i>during salinization to understand the effects on species and ecosystems. We follow 170 years of <i>Daphnia </i>dynamics in the sediment ephippia archive of a small urban lake near St. Paul, Minnesota, to characterize effects of severe recent salinization on lake<i> Daphnia</i>. We found modest changes in the flux of ephippia in this lake; all three key <i>Daphnia </i>functional groups remained in the assemblage throughout the period of salinization. Reconstruction of the size distribution of <i>D. pulicaria </i>demonstrated that predation pressure by fish may not have increased for the largest and most susceptible member of the assemblage despite cultural meromixis. Our findings highlight that in hardwater lakes, the effects of salinization are nuanced and require further investigation to better understand overall impacts of salinization on lake <i>Daphnia </i>assemblages.</p>
Lake water and sediments chemistry data along with temporal data on environmental drivers
<p class="Abstract">Increasing iron (Fe) concentrations are found in lakes on a wide geographical scale but exact causes are still debated. The observed trends might result from increased Fe loading from the terrestrial catchment, but also from changes in how Fe distributes between the water column and the sediments. To get a better understanding of the causes we investigated whether there has been any change in the sediment formation of Fe sulfides (FeS) as an Fe sink in response to declining atmospheric sulfur (S) deposition during recent decades. For our study, we chose Lake Bolmen in southern Sweden, a lake for which we confirmed that Fe concentrations in the water column have strongly increased along with water color during 1966 to 2018. Our investigations showed that Fe accumulation and speciation varied independently of S accumulation patterns in the Lake Bolmen sediment record. Thus, we were not able to relate the positive trend in Fe concentrations to reduced FeS binding in the sediments. Furthermore, we found that Fe accumulation rates increased along with lake Fe concentrations, indicating that increased catchment loading rather than a change in the distribution between the sediments and the water column has driven the increase in Fe concentrations. The increased loading may be due to land-use change in the form of an extensive expansion of coniferous forest during the past century. Altered forest management practices and increased precipitation may have led to enhanced weathering and erosion of organic soil layers under aging coniferous forest.</p>
Records of chemical weathering and plateau saline lake sediments linked to paleoclimate fluctuations during the Eocene
Open the record for dataset details and reuse information.
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.