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NSC01 Chemistry and physical characteristics of soils from Konza LTER watersheds with different fire and grazing treatments
Soil chemical and physical characteristics are quantified on selected LTER watersheds adjacent to LTER vegetation sampling plots. Sampling was initiated in 1982, and is repeated every five years. A subset of variables (e.g., pH, Bray extractable P, total C, exchangeable cations) is measured on all sample dates, while additional specific variables (e.g., bulk density, soil texture, CaCO3 content, trace metals, extractable inorganic N) are measured less frequently. Methods for C and N analysis have changed over time. C content of samples from 1982, 1987 and 1997 was derived from Walkley-Black measurements of % soil organic matter (OM) content, using a conversion factor of 1.72 (%C = %OM / 1.72). Soil C content of samples from 1992, 2002 and later were determined by dry combustion and gas chromatography (i.e., Carlo-Erba C/N analyzer). N content of samples prior to 1992 was based on Kjeldahl digeston. N content of samples from 1992 on were determined by dry combustion and gas chromatography (i.e., Carlo-Erba C/N analyzer). Additional details regarding sampling protocols and analytical methods are available in the Konza LTER Methods Manual.
NTF01 Volume and chemistry of throughfall in tallgrass prairie
Amounts and nitrogen content of water passing through the canopy of tallgrass prairie are compared to similar measurements of bulk precipitation. Measurements include nitrate, ammonia, phosphate and organic nitrogen and phosphorus content of bulk precipitation and throughfall. Variables of interest include vegetation type and amounts, time of year, and time since burning.
NWC01 Stream water chemistry for the king's creek drainage basin on Konza Prarie
Nitrate, ammonium, total N, soluble reactive P, total P, and dissolved organic C are monitored in four streams draining watersheds with 1 (N01B), 2 (N02B), 4 (N04D), and 20 (N20B) year target burn frequencies. Bison have grazed these treatments since May 1992. The number of sites sampled has been expanded since 1992 to include sites that may reflect anthropogenic, groundwater, and bison influences on water chemistry. These sites include the south branch of Kings Creek as it leaves watershed N01A (tube), a site immediately below the NO4D weir at Konza Falls that is heavily influenced by groundwater (kzfl), the north fork of Kings Creek draining watersheds without bison (nfkc), the south fork of Kings Creek that drains the watersheds with bison (sfkc), Kings Creek below the USGS gauging station above the first agricultural field (hokn), a small creek that drains into Kings Creek after flowing past the bison handling facilities, two private residences, the site headquarters and an agricultural field (stck), a pristine prairie groundwater site (edlr), and Kings Creek at the bottom of Konza as it leaves the agricultural land in watershed AL (hikx). Early samples were preserved with phenyl mercuric acetate. Future plans to restore agricultural land to prairie may influence downstream nutrient concentrations.
Rio Icacos hyporheic and riparian chemistry
Hydrologic and chemical characteristics were determined for both riparian and hyporheic subsurface flow along a 100-m reach of a sandy-bottom tributary of the Rio Icacos in the Luquillo Experimental Forest, Puerto Rico. Hydrologic data (vertical hydraulic gradient and hydraulic conductivity of streambed sediments) and the topographic and morphological features of the watershed indicated diffuse inputs of groundwater from the near-stream riparian zone along this site. Cumulative groundwater discharge, determined by tracer dilution techniques, was ~1.5 L/s or 10% of the total stream discharge. Spatial heterogeneity in hydrologic and chemical properties of riparian and hyporheic sediments was large. Hydraulic conductivity explained much of the variation in NH4-N and dissolved organic carbon (DOC) concentrations, with highest concentrations in sites having low conductivity. A mass-balance approach was used to examine the influence of the near-stream zone on nutrient transport and retention. Outwelling riparian groundwater had the potential to increase stream N concentrations by up to 84% and DOC concentrations by up to 38% along our 100-m reach. Because stream concentrations were constant downstream despite this input, we conclude that significant N and C retention or loss were occurring in the near-stream zone. Lotic ecosystems and their associated riparian groundwater can have a quantitatively significant impact on the nutrient budgets of tropical headwater catchments. Support for this work was provided by grants BSR-8811902, DEB-9411973, DEB-9705814 , DEB-0080538, DEB-0218039 , DEB-0620910 , DEB-1239764, DEB-1546686, and DEB-1831952 from the National Science Foundation to the University of Puerto Rico as part of the Luquillo Long-Term Ecological Research Program. Additional support provided by the University of Puerto Rico and the International Institute of Tropical Forestry, USDA Forest Service.
Bromeliad chemistry at different elevations in the LEF
Mean concentrations of various nutrients in dried bromeliad leaf and in the coarse, medium and fine portions of debris retained by the bromeliad rosette. Support for this work was provided by grants BSR-8811902, DEB-9411973, DEB-9705814 , DEB-0080538, DEB-0218039 , DEB-0620910 , DEB-1239764, DEB-1546686, and DEB-1831952 from the National Science Foundation to the University of Puerto Rico as part of the Luquillo Long-Term Ecological Research Program. Additional support provided by the University of Puerto Rico and the International Institute of Tropical Forestry, USDA Forest Service.
Bisley rainfall and throughfall, and chemistry of rainfall and throughfall
This data set contain summaries and analyses mean of collected weekly measurements expressed as mm per day, and calculation of fluxes, rates and means calculated after water chemistry analyses are conducted. Rainfall and throughfall are collected weekly at the Bisley LEF site. These data sets begin March 1988 and ends December 2003. Rain and throughfall samples are the total catch for the week, and are exposed to field conditions for that time. No event sampling is conducted on a routine basis. Rainfall Collected in Bisley (RCB) are bulk or always-open collectors that receive dry deposition by sedimentation. All samples are measured for pH and conductivity, and then filtered (pre-combusted Whatman GF/F glass fiber filter) prior to further analysis. From 1983-1994 samples were cooled and returned to the San Juan chemistry laboratory for analysis. During those years, samples for NH4 and NO3 analyses were refrigerated continuously until analysis. Sub samples for NH4 analysis were also preserved with 1 molar HCl. From 1994 on, samples for NH4 and NO3 were frozen until analysis, were not acidified, and all analyses were conducted at the University of New Hampshire. Nutrient fluxes in rainfall and throughfall were measured weekly in a mature subtropical wet forest in NE Puerto Rico over a 15-year period that included the effects of five hurricanes and several prolonged droughts. Annual inputs of K, Ca, Mg, Cl, Na, and SO4-S are similar to those reported from other marine-influenced tropical forests. Rainfall input of nitrogen is comparatively low and reflects the relative isolation of the air shed. Mean annual rainfall and throughfall were 3482 and 2131 mm yr-1 respectively. On average, rainfall, throughfall, rainfall pH, and rainfall flux NH4-N and NO3-N had small but significant decreases throughout the study period. More nutrients fluxes had seasonal differences in rainfall (6 out of 12) than throughfall (4 out of 12). All volume weighted enrichment ratios calculated f
Chemistry of soil solution collected from tension lysimeters in the Canopy Trimming Experiment (CTE) plots
Soil solution chemistry: Soil solution was collected monthly from tension lysimeters installed in the CTE plots. Sampling began prior to cutting the canopy and continue to the present. Support for this work was provided by grants BSR-8811902, DEB-9411973, DEB-9705814 , DEB-0080538, DEB-0218039 , DEB-0620910 , DEB-1239764, DEB-1546686, and DEB-1831952 from the National Science Foundation to the University of Puerto Rico as part of the Luquillo Long-Term Ecological Research Program. Additional support provided by the University of Puerto Rico and the International Institute of Tropical Forestry, USDA Forest Service.
Chemistry of rainfall and throughfall from El Verde and Bisley
Rain, throughfall, and stream water are collected weekly at the LEF sites listed below. Samples are collected by USDA Forest Service technicians Carlos Estrada in the field filtered in the lab by Miriam Salgado. These data sets begin as early as 1983; LTER sampling began in 1988. Rain and throughfall samples are the total catch for the week, and are exposed to field conditions for that time. No event sampling is conducted on a routine basis. Rain samples from WDEV are wet only from an automatically-closing collector that prevents any dry deposition (Aerochem Metrics NADP collector). RCEV and RCB are bulk or always-open collectors that receive dry deposition by sedimentation. All samples are measured for pH and conductivity, and then filtered (pre-combusted Whatman GF/F glass fiber filter) prior to further analysis. From 1983-1994 samples were cooled and returned to the San Juan chemistry laboratory for analysis. During those years, samples for NH4 and NO3 analyses were refrigerated continuously until analysis. Subsamples for NH4 analysis were also preserved with 1 molar H2SO4. From 1994 on, samples for NH4 and NO3 were frozen until analysis, were not acidified, and all analyses were conducted at the University of New Hampshire. Rain and Throughfall Sampling SitesDescriptions of LTER LUQ rain and throughfall weekly sample chemistry data from 1988 onwards. Chemical concentrations are recorded as mg/L or ug/L as appropriate. Values below detection limits are recorded as 1/2 the detection limit. Site Abbreviation Description Comments Rain collector Bisley. RCB Bulk collector. Rain collector El Verde RCEV Bulk collector. Wet/dry El Verde. WDEV. Wet only collector. Throughfall Bisley. TFB=TCB TF bulk 10-collector composite Bisley gap= BGAP, TF bulk 10-collector composite Support for this work was provided by grants BSR-8811902, DEB-9411973, DEB-9705814 , DEB-0080538, DEB-0218039 , DEB-0620910 , DEB-1239764, DEB-1546686, and DEB-1831952 from the National Science Foundation
Chemistry of stream water from the Luquillo Mountains
Stream water is collected weekly at the Luquillo Mountain (Luquillo Experimental Forest) sites listed below. These data sets begin as early as 1983; LTER sampling began in 1988. Stream water samples are grab samples taken from the water/air interface at stream channel center on the sampling day (usually Tuesdays). A continuous record of stream stage (height) is recorded by a datalogger at some ongoing stream sampling sites. Average daily streamflows are available from the USGS and at other locations (Hydrology and Meteorology) on this site. All samples are measured for pH and conductivity, and then filtered (pre-combusted Whatman GF/F glass fiber filter) prior to further analysis. From 1983-1994 samples were cooled and returned to the San Juan chemistry laboratory for analysis. During those years, samples for NH4 and NO3 analyses were refrigerated continuously until analysis. Subsamples for NH4 analysis were also preserved with 1 molar H2SO4. From 1994 on, samples for NH4 and NO3were frozen until analysis, were not acidified, and all analyses were conducted at the University of New Hampshire. Stream water Sampling SitesDescriptions of LTER LUQ stream water weekly sample chemistry data from 1988 onwards. Chemical concentrations are recorded as mg/L or mg/L as appropriate. Values below detection limits are recorded as 1/2 the detection limit. Support for this work was provided by grants BSR-8811902, DEB-9411973, DEB-9705814 , DEB-0080538, DEB-0218039 , DEB-0620910 , DEB-1239764, DEB-1546686, and DEB-1831952 from the National Science Foundation to the University of Puerto Rico as part of the Luquillo Long-Term Ecological Research Program. Additional support provided by the University of Puerto Rico and the International Institute of Tropical Forestry, USDA Forest Service. The following sites in the Luquillo Experimental Forest (LEF) are represented here: Quebrada Sonadora, QS, El Verde stream. Quebrada Toronja, QT, QT1 El Verde stream. Rio Espiritu Santo 4, RES4, LEF N
Chemistry of coastal stream and lagoon water from Puerto Rico - 2021-2024
Water samples were collected from coastal streams and lagoons in Puerto Rico from February 2021 to March 2024 as part of ongoing coastal ecosystem monitoring. These samples were analyzed at the University of New Hampshire Water Quality Analysis Laboratory for comprehensive water chemistry including field parameters, major ions, nutrients, dissolved gases, and trace metals. Sampling sites included Quebrada Fajardo (QFJO) at multiple depths and distances upstream, Quebrada Pitahaya (Qpaya), Laguna Pitahaya (LPYHA), Luquillo streams (LUQA, LUQB), and Laguna Cartagena (LCART). Field measurements included pH, conductivity, dissolved oxygen, temperature, turbidity, and atmospheric pressure. Laboratory analyses encompassed dissolved organic carbon (DOC), total dissolved nitrogen (TDN), nutrients (NH4-N, PO4-P, NO3-N), major ions (Cl, SO4, Na, K, Mg, Ca), dissolved gases (CH4, CO2, N2O), and trace metals by Inductively Coupled Plasma (ICP) analysis. The ICP analysis provided enhanced detection capabilities for cations and metals including calcium, iron, manganese, silicon, strontium, sulfur, sodium, magnesium and potassium. Samples were collected as grab samples from the water surface. All samples were filtered through pre-combusted Whatman GF/F for nutrients and organic matter and Whatman WCN Cellulose Nitrate Membranes for metals. Values below detection limits are recorded as 1/2 the detection limit. This dataset provides comprehensive water quality data for Puerto Rican coastal watersheds, with particular focus on stratified sampling in Quebrada Fajardo to understand vertical water column structure and biogeochemical processes in coastal environments influenced by both terrestrial and marine inputs. Support for this work was provided by grants BSR-8811902, DEB-9411973, DEB-9705814 , DEB-0080538, DEB-0218039 , DEB-0620910 , DEB-1239764, DEB-1546686, and DEB-1831952 from the National Science Foundation to the University of Puerto Rico as part of the Luquillo Long-Term Ecol
NADP/NTN precipitation chemistry data
This dataset links to the NADP data repository for the chemistry of weekly wet-only rainfall from the Luquillo Experimental Forest (LEF) NADP station (code PR20). Our station was knocked out by Hurricane Hugo in September 1989, and not reestablished until May 1991. The station remains in active service to the present and data from 1997 onwards is available directly from the NADP/NTN web site https://nadp.slh.wisc.edu/sites/ntn-PR20/. Samples are collected weekly on Tuesdays, field measurements of pH and conductivity are made, and the water sample is shipped to NADP for chemical analysis. Sub-samples are also shipped to the University of New Hampshire Water Quality Analysis lab and those data are available in the EDI dataset: https://portal.edirepository.org/nis/mapbrowse?scope=knb-lter-luq&identifier=174 Support for this work was provided by grants BSR-8811902, DEB-9411973, DEB-9705814 , DEB-0080538, DEB-0218039 , DEB-0620910 , DEB-1239764, DEB-1546686, and DEB-1831952 from the National Science Foundation to the University of Puerto Rico as part of the Luquillo Long-Term Ecological Research Program. Additional support provided by the University of Puerto Rico and the International Institute of Tropical Forestry, USDA Forest Service.
MCR LTER: Coral Reef: Water Column: Nearshore Water Profiles, CTD, Primary Production, and Chemistry ongoing since 2005
This data package contains water chemistry measurements taken 2 to 4 times per year at 6 stations on the north shore of Moorea, French Polynesia: Forereef, Lagoon, Fringing Reef, Cooks Bay, Cooks Bay Stream Mouth, and Offshore (5 km due north). Measurements include standard CTD parameters, nutrients, chlorophyll, phaeopigments, particulate organic carbon and nitrogen, dissolved organic carbon, dissolved inorganic carbon, total alkalinity, water column primary production, and abundance of bacteria. Sampling began in August, 2005. All water samples were collected with Niskin Bottles. CTD data were collected with a SBE19-Plus Seacat Profiler outfitted with WetLabs FLNTURT-221 Flurometer/turbidity sensors. CTD and bottle samples were taken on separate casts at each station. Two additional stations on the Moorea east shore were sampled in August 2005 only: LTER 3 Forereef Water Column, LTER 3 Backreef Water Column. This material is based upon work supported by the U.S. National Science Foundation under Grant No. OCE 16-37396 (and earlier awards) as well as a generous gift from the Gordon and Betty Moore Foundation. Research was completed under permits issued by the French Polynesian Government (Délégation à la Recherche) and the Haut-commissariat de la République en Polynésie Francaise (DTRT) (Protocole d'Accueil 2005-2018). This work represents a contribution of the Moorea Coral Reef (MCR) LTER Site.
MCR LTER: Coral Reef: Water Column: Offshore Ocean Acidification: Water Profiles, CTD, and Chemistry from 2005 to 2012
This data package contains water chemistry measurements taken 2 to 4 times per year at a station 5 km offshore of the north shore of Moorea, French Polynesia. Measurements include standard CTD parameters, phosphate, silicate, total alkalinity (TA) and total dissolved inorganic carbon (DIC). Sampling began in August, 2005. All water samples were collected with Niskin Bottles. This data includes excerpts from CTD data were collected with a SBE19-Plus Seacat Profiler. CTD and bottle samples were taken on separate casts at each station. (For full CTD data refer to knb-lter-mcr.10.) All other parameters were calculated from temperature, pressure, nutrients, TA and DIC with CO2Sys programs available at: http://cdiac.ornl.gov/oceans/co2rprt.html (Lewis E. and D. Wallace Program Developed for CO2 System Calculations) using constants K1, K2 from Mehrbach et al, 1973 refit by Dickson and Millero, 1987, Dickson KHSO4, and the Seawater pH scale (mol/kg-SW). If users wish to use different constants and scales, they will need to recalculate using the emperically collected data (TA and DIC).
Greenhouse gas and water chemistry data from urban ponds in Madison, Wisconsin during the summer and under-ice period of 2021-2022
Stormwater ponds are common features in urbanized landscapes and can suffer from rapid oxygen depletion when thermally stratified or ice-covered. To investigate under-ice oxygen dynamics and drivers of bottom water oxygen saturation, we sampled 20 stormwater ponds in Madison, Wisconsin, USA during the summer of 2021 and winter 2022. The urban ponds ranged in age, shape, size, and depth. We repeatedly took YSI profiles of water temperature, oxygen, and specific conductance 7 times in the summer and 3 times in the winter. Water chemistry variables were collected in the surface waters, habitat surveys were conducted in the summer, and ice/snow thickness was recorded in the winter. We also measured the concentration of greenhouse gases in the surface waters as a consequence to oxygen depletion using the headspace equilibrium method.
Stream water chemistry data for Green Lake 5 outlet, 1984 - ongoing.
This is a summary of major ion concentrations for stream water samples collected from the outlet stream at Green Lake 5.
Stream water chemistry data for Lake Albion inlet, 1984 - 2004.
This is a summary of major ion concentrations for stream water samples collected at the old parshall flume at the inlet to Lake Albion.
Stream water chemistry data for Navajo meadow, 1984 - ongoing.
This is a summary of major ion concentrations for stream water samples collected at the flow gauging site at the lower end of the Navajo meadow. Marked by rebar in channel.
Stream water chemistry data for Lake Albion spillway, 1984 - 2004.
This is a summary of major ion concentrations for stream water samples collected at the spillway from Lake Albion. At times when the lake level was below the spillway, no samples were taken.
Surface and porewater chemistry and sulfur stable isotpes for alpine and subalpine wetland sites, 2021.
To understand patterns in aqueous biogeochemistry of wetlands at Niwot Ridge, samples were collected and analyzed for dissolved anions and stable isotopes of sulfur in 2021. Samples were collected from eight wetland sites representing three wetland types, from the Saddle into the subalpine. At each site, tension lysimeters were placed at visible surface inflow and outflow paths to collect porewater. Water samples were collected from the tension lysimeters and surface pools during four time points through the summer season. Water samples were measured for a suite of dissolved anions using ion chromatography, including dissolved chloride, nitrate, and sulfate. Samples were also measured for dissolved organic carbon. Sulfur from one surface water sample from each site at each time point was precipitated as barium sulfate, and precipitations were analyzed for stable sulfur isotope ratio (δ^34S-SO4^2-) at the Center for Stable Isotope Biogeochemistry at the University of California, Berkeley. Data was used in conjunction with soil biogeochemistry data from 2020 to evaluate patterns in reactants among wetland types.
PIE LTER, stable isotope chemistry (carbon, nitrogen and sulfur) for food web analysis of functional groups in the Plum Island Sound Estuary, Massachusetts.
Stable isotopes of primary producers will be compared to stable isotopes of functional groups of organisms at primarily three sites within the estuary that have different dominant sources of organic matter. The three sites are: Lower (IBYC, SO-3, mouth of Plum Island Sound, 2-3 km upstream of the mouth of the estuary), Middle (OTL, PR-10.1, upper Sound, lower Parker, 8-11 km upstream of the mouth of the estuary) and Upper (P2, PR-21.9, upper Parker, above Middle Rd Bridge (22 km upstream of the mouth of the estuary). The Lower site is dominated by marine phytoplankton, the Middle site is dominated by a mixture of salt marsh and phytoplankton and the Upper site is dominated by oligohaline phytoplankton and fresh marsh. Ten functional groups will be sampled at each site (Surface sediment, benthic diatoms, Nereis, mummichog, ribbed mussels, POM, blue mussels, pelagic copepods (Acartia), silversides and soft shell clams (Mya). Marsh, benthic algae and phytoplankton inputs or benthic vs. pelagic pathways will be evident in the isotopic signals of these functional groups. Samples will be collected between the middle and end of August to reflect a growing season using recently produced OM. Samples of 15 – 20 individuals will be pooled for analysis. Some silverside samplings will have 3 different pooled samples for determination of variance. Often times the same species are not collected at each site due to habitat differences (salinity/discharge) so additional species are collected to try to accomplish task of getting functional groups collected.
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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)
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DANDI Archive for NWB datasets
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International Brain Laboratory public data
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OpenNeuro
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