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.
1,781
datasets available to search
ShareScore release 0.9.0
Dataset results
1,781 results for “2002”
Cold air drainage transect studies at the Andrews Experimental Forest, 2002 to Present
Temperature data are being collected to investigate the effects of elevation and local topographic position on the patterns of cold air drainage and pooling in the HJ Andrews Forest, and how they vary with synoptic weather patterns. The main focus of the study is cold air drainage in the Lookout Creek area, but others sites have been added to sample temperature signatures at other locations of the forest with topographic positions that need to be better understood. Here, quality controlled 15-minute raw data and aggregated daily minimum and maximum temperatures are available from several stations along 4 separate transects or clusters with some additional single sensors also included. Several of the quality flags indicate that the data failed the test and should not be used in analysis.
Overnight Shark River Surveys from Shark River Slough, Everglades National Park (FCE), South Florida from October 2001 to March 2002
Estuarine mixing interfaces have been a focus of wetland ecologists for the last three decades and are of growing concern today. Particularly critical in Everglades restoration, water quality and the dynamics of nutrients and dissolved materials across seasons in the natural system are being defined. We measured diurnal and seasonal (wet and dry) variation in microbial, dissolved and total nutrients and total organic carbon along a riverine transect and for a diurnal cycle in October of 2001 and March of 2002. For the diurnal sampling we anchored a houseboat mid Shark River 100m up river of the mesohaline Florida Coastal Everglades Shark River LTER site and sampled the water for chemical, microbial, and physical parameters. At slack high and low tides we sampled 10 miles offshore then at three sites up the Shark River. TOC (mM) and salinity (ppt) were highly correlated (r2 .97) along the river transect across seasons and TOC derived from terrestrial input. Bacterial production ranged from 1.88 to 10.99 mg C l-1 d-1 and was greatest in the dry season and at the most freshwater sampling points. Combined examination of our 49 sampled parameters both from the diurnal sampling and river transect sampling showed that our position for sampling in the river was critical and that the mid river-estuarine productivity maxima occurred within Shark River in both the wet and dry season. These data suggest this oligotrophic estuarine-river system is highly sensitive to watershed and river fringe nutrient inputs and remineralization vectors within the river.
Soil Characteristic and Nutrient Data from the Taylor Slough, within Everglades National Park (FCE), from March 2002 to April 2004
Three random soil cores are collected once a year from TS/Ph 1b, 2, 3, 4, 5, & 6b. The collection of these soil cores is in the dry season (Dec.-May). The top 10cm of soil is collected using a soil core. The soil is then analyzed to obtain its bulk density, organic matter content, TC, TN, and TP.
Litterfall at Harvard Forest HEM and LPH Towers since 2002
We measure the dry mass and estimated carbon content of leaves and fine twigs that abscise each year. These data are used to quantify one component of annual net primary productivity (ANPP), an important measure of ecosystem productivity and carbon cycling. Leaf area index (LAI) can also be estimated from these data, if area-to-mass ratios are calculated for leaves of each species. This was done for 2002 and 2003 leaf litterfall at the Little Prospect Hill (LPH) site. The fraction of total leaf mass or estimated total leaf area that is formed by leaves of each species also shows the species composition of the forest canopy. If repeated over many years, these data can indicate whether the forest canopy species composition is changing over time.
Effect of Prey Availability on Sarracenia Purpurea Stoichiometry at Belvidere Bog, Vermont 2002
The carnivorous pitcher plant Sarracenia purpurea receives nutrients from both captured prey and atmospheric deposition, making it a good subject for the study of ecological stoichiometry and nutrient limitation. We added prey in a manipulative field experiment and measured nutrient accumulation in pitcher-plant tissue and pitcher liquid, as well as changes in plant morphology, growth, and photosynthetic rate. Prey addition had no effect on traditional measures of nutrient limitation (leaf morphology, growth, or photosynthetic rate). However, stoichiometric measures of nutrient limitation were affected, as the concentration of both N and P in the leaf tissue increased with the addition of prey. Pitcher fluid pH and nitrate concentration did not vary among treatments, although dissolved oxygen levels decreased and ammonia levels increased with prey addition. Ratios of N:P, N:K, and K:P in pitcher-plant tissues suggest that prey additions shifted these carnivorous plants from P limitation under ambient conditions to N limitation with the addition of prey.
Stoichiometry of Bogs and Bog Plants in Massachusetts and Vermont 2002
Geographic trends in surface water chemistry and leaf tissue nutrients may reflect gradients of nutrient limitation and broad-scale anthropogenic inputs. In 24 bogs and poor fens in Massachusetts and Vermont, we measured nutrient and metal concentrations in pore-water and in leaf tissues of three common bog plants – leather leaf (Chamaedaphne calyculata), northern pitcher plant (Sarracenia purpurea), and peat moss (Sphagnum spp.). The concentrations of N, P, and K were low in leaf tissues of all three plant genera, as were the concentrations of many trace heavy metals, including Cr, Cu, Co, Cd, Mo, and Pb. Stoichiometric ratios of macronutrients (N:P, P:K, and N:K) in plant leaves suggested that plant growth in the sampled bogs was limited by P, or was co-limited by all three macronutrients. N:P and N:K nutrient ratios of Sarracenia purpurea and Sphagnum spp. increased toward the northwest and with elevation, but stoichiometric ratios of Chamaedaphne calyculata did not show any clear geographic trends. A principal components analysis revealed additional distinct differences among the three plant genera in their nutrient and metal concentrations. Furthermore, dissolved organic carbon (DOC), dissolved organic nitrogen (DON), Cu, Mg, NO3, Al, and K in porewater increased from the northwest (northwestern Vermont) to the southeast (Cape Cod and eastern Massachusetts near Boston), a gradient of increasing human population density and urbanization. In contrast, pore-water concentrations of SO4 and Al were highest in the western sites, and SO4 concentrations increased with elevations. These patterns may reflect atmospheric inputs from the Ohio River Valley leading to increased acidic deposition, causing Al to be leached from soils. Because bogs are naturally low in nutrients and do not receive substantial inputs from surrounding groundwater, the chemical signatures and nutrient stoichiometry of specific bog plant species or genera may provide useful indicators for assessing
Hemlock Understory Vegetation Plots at Harvard Forest since 2002
Hemlock (Tsuga canadensis) forests in New England are changing rapidly with the invasion of the hemlock woolly adelgid (HWA, Adelges tsugae), a non-native insect pest that kills hemlock trees. As the adelgid invades hemlock stands at Harvard Forest, we are monitoring how forest structure and function changes. We surveyed community vegetation structure and composition prior to adelgid infestation, and are repeating this survey as infestation progresses. These measurements will allow us to link the long-term history of these hemlock stands to other current studies of hemlock response to adelgid infestation.
Net Carbon Exchange of a Young Upper-Slope Deciduous Forest at Harvard Forest LPH Tower 2002-2010
This data set contains sensible heat exchange, water vapor exchange and carbon exchange as well as environmental data for a deciduous forest dominated by red oak (Quercus rubra). It is 1.1 km WNW of the EMS tower where continuous eddy covariance measurements began in 1992 (see HF004). The High Deciduous site is about 385 m a.s.l., or 35 m higher in elevation than the EMS, which is situated in a relatively low area near a stream. The forest near this eddy covariance tower is broadly similar in species composition to the EMS site, but it is younger and shorter in stature. The site was cleared for pasture, but not deeply plowed or planted, in the 18th and19th centuries. Agriculture on the site was abandoned near the end of the 19th century. The forest within 200 to 300 m of the eddy covariance tower to the NW, W, SW, and S burned in an intense fire in 1957, which left few or no surviving trees.
Impact of Hemlock Woolly Adelgid on Canopy Throughfall in Southern New England 2002
Non-native insect pests may strongly disrupt forest ecosystems and trigger major shifts on nutrient cycling, structure and composition. Although the immediate impact of these pests are frequently examined as physical disturbances (i.e., defoliation, decline in leaf area, and tree mortality) that initiate changes in ecosystem function, the insects often generate fundamental biochemical and trophic changes in tree canopies that may be equally important in altering ecosystem dynamics. Consequently, investigation of the linkages between canopy-level, ecosystem and environmental impacts may be critical for a thorough understanding of functional, structural, and compositional changes resulting from pest infestation. We sought to establish a better understanding of these linkages for the hemlock woolly adelgid (HWA), which is devastating hemlock forests in an expanding region across eastern North American and has the potential to eliminate this long-lived and extremely shade-tolerant species across much of its range. We examined the impact of the adelgid on hemlock needle chemistry and epiphytic microorganisms, litter production, and shoot growth in stands differing in their levels of infestation and linked these to shifts in canopy nutrient cycling and stand and landscape dynamics. HWA initiated major changes in canopy biomass and distribution. Whereas uninfested trees exhibit a decline in canopy biomass from the center to the periphery and a positive correlation between total needle litter and estimated biomass, infested trees support predominantly woody biomass, have significantly less total canopy biomass, produce less new foliage and exhibit no correlation between litter and canopy biomass. Foliar %N was strongly influenced by needle age and the level of infestation and was highest in young foliage supporting the highest densities of HWA. Foliar %C was unaffected by HWA or foliar age. Epiphytic microorganisms on hemlock needles exhibited little variation in abundance
Hydraulic Pathways in Leaves of Temperate Trees at Harvard Forest 2002
The transport of water, sugar and nutrients in trees is restricted to specific vascular pathways, and thus organs may be relatively isolated from one another (=sectored). Strongly sectored leaf-to-leaf pathways have been shown for the transport of sugar and signal molecules within a shoot, but not previously for water transport. The hydraulic sectoriality of leaf-to-leaf pathways was determined for current year shoots of six temperate deciduous tree species (three ring-porous: Castanea dentata, Fraxinus americana and Quercus rubra, and three diffuse-porous: Acer saccharum, Betula papyrifera and Liriodendron tulipifera). Hydraulic sectoriality was determined using dye staining and a hydraulic method. In the dye method, leaf blades were removed, and dye was forced into the most proximal petiole. For each petiole we counted the vascular traces shared with the proximal petiole. For other shoots, measurements were made of the leaf-area specific hydraulic conductivity for leaf-to-leaf pathways (kLL). In five of six species patterns of sectoriality reflected phyllotaxy; both the sharing of vascular bundles between leaves and kLL were higher for orthostichous than non-orthostichous leaf pairs. Species-differences in leaf-to-leaf sectoriality were determined as the proportional differences between non-orthostichous vs. orthostichous leaf pairs in their staining of shared vascular bundles and in their kLL; for the six species these two indices of sectoriality were strongly correlated (R2 = 0.94; P less than 0.001). Species varied 8-fold in their kLL-based sectoriality, and ring-porous species were more sectored than diffuse-porous species. Differential leaf-to-leaf sectoriality has implications for species-specific coordination of leaf gas exchange and water relations within a branch, especially during fluctuations in irradiance, water and nutrient availability.
Headwater Habitat Streams in Central Massachusetts 2002-2005
Headwater streams, particularly those that flow only during part of the year, are understudied and underprotected in Massachusetts. Research being conducted elsewhere suggests that these "Headwater Habitat Streams" are important both for aquatic biodiversity and for ecological function of lower stream reaches. We are carrying out baseline research, involving research scientists and volunteers, on hydrology and habitat characteristics in headwater streams in northern Worcester County, MA. We hypothesized that headwater streams exhibit a longitudinal gradient of hydrology, from (1) ephemeral channels that flow only in response to storms, through (2) intermittent sections that flow seasonally until the groundwater table falls below the channel and are dry the rest of the year, to (3) interstitial reaches that flow seasonally and retain pools connected by subsurface flow during the summer, to (4) the perennial stream. Results to date show a high degree of longitudinal heterogeneity in the study streams, with interspersion of perennially flowing reaches among low-gradient sections of vegetated wetland, high-gradient boulder piles, and braided channels. Perennial flow is found high up in some watersheds. We expect our methods and results will have implications throughout the Commonwealth for local conservation commissions and other municipal officials responsible for land-use planning and regulation, state agencies responsible for land management and the protection of wildlife, regulators reviewing projects affecting streams, watershed managers, teachers and their students, private land trusts, conservation advocates, and citizen-naturalists.
City of Seattle, Seattle Public Utilities, Amphibian Egg Mass Counts 2002 - Current, Cedar River Municipal Watershed, King County, WA
This data package contains survey data beginning in 2002 for amphibian egg masses in five small kettle lakes (known as "14 Lakes") in the Cedar River Municipal Watershed, located in King County, Washington, USA. These surveys are conducted annually and are intended to be continued. The lakes range in size from 0.8 to 4.3 acres, have no perennial inlet or outlet, and were formed through glacial outwash deposits. The lakes are located at an elevation of 800 feet and are well suited for pond breeding amphibians because the lakes have no fish. Surveys were conducted annually, typically during the last week of March or first week of April, to coincide with amphibian breeding seasons. Surveyors walked, waded, or paddled the perimeter of each of the lakes during a survey, and tallied the number and type of egg masses that were encountered. Red legged frogs (Rana aurora) were of specific interest for the surveys, though egg masses of other species were noted during some survey years. The lakes represent the largest known breeding concentration of red legged frogs in the municipal watershed. The water depth of the lakes fluctuates year-to-year, which affected the feasibility of surveys. Lower water levels correspond to easier survey conditions: steep slopes and thick vegetation make surveying challenging when the water is high. Surveys were periodically cancelled during years where high water made surveying difficult or during staffing shortages. Counts of red legged frog egg masses across all lakes ranged between 24 and 1778 in a given year.
Lower American River steelhead spawning surveys (Chinook and lamprey data included), California, 2002 to 2025
Steelhead spawning surveys have been conducted on the Lower American River (LAR) for the years 2002-2005, 2007, and 2009-2025. These surveys in conjunction with annual escapement estimates to Nimbus Fish Hatchery, are used to provide a yearly index of in-river and over all spawning abundance. Reclamation’s mission is to manage, develop and protect water and related resources in an environmentally and economically sound manner in the interest of the American people. In the National Marine Fisheries Service (NMFS) most recent biological opinion (2009), the presence of dams was identified as the most influential stressor to steelhead on the American River because it blocks passage to historic spawning and rearing habitat. Thus, Reclamation is required to monitor the effects of flow regulation by dams on the steelhead life stages present in the river system. Congruently, Reclamation has committed to significant restoration actions including salmonid spawning and rearing habitat rehabilitation on the Lower American River, which also require accurate and robust monitoring. These surveys support the mission and monitoring requirements of Reclamation by collecting the spawning data required to effectively conduct analyses of the effects of regulating Folsom and Nimbus dams on this federally listed species’ critical life stage development and support operational decision making.
Nutrient Loading and Benthic Macroinvertebrate Assessments in Michigan Streams (2002-2021)
The assembled data package, including both nutrients and benthic macroinvertebrate assessments from stream monitoring sites in Michigan (USA), is part of the project entitled "Long-Term Nitrogen and Phosphorus Dynamics and Macroinvertebrate Assemblages in Temperate Streams." These datasets encompass records from January 1, 2002, until December 31, 2021, that were extracted from the Water Quality Portal (www.waterquality.us). We were aiming to examine the influence of landscape settings on the concentration of N and P constituents in streams and rivers, and determine the effects of land use on benthic macroinvertebrates in the interaction with these nutrients over 20 years. Records were cleaned and analyzed to determine the influence of land use settings on nutrient concentrations and benthic macroinvertebrate composition statewide. All data tables feature monitoring sites with sampling dates, identifiers, and GPS coordinates.
Biogeochemistry data set for Imnavait Creek Weir on the North Slope of Alaska 2002-2024.
Data file containing biogeochemical data of water samples collected in Imnavait Creek, North Slope of Alaska. Sample site descriptors include a unique assigned number (sortchem), site, date, time, depth, distance (downstream), and elevation. Values of variables measured in the field include temperature, conductivity, pH. Chemical analysis for samples include alkalinity, dissolved organic carbon (DOC), inorganic and total dissolved nutrients particulate carbon, nitrogen, and phosphorus, cations and anions.
Above ground plant and below ground stem biomass in the Arctic LTER acidic tussock tundra experimental plots, 2002, Toolik Lake, Alaska.
Above ground plant and below ground stem biomass and their carbon and nitrogen content was measured in the Arctic LTER moist acidic tussock tundra experimental plots(MAT89). Treatments included control, nitrogen plus phosphorus amended plots for either 6 or 13 years and vole exclosure plots with or without amends of nitrogen and phosphorus. Note: The added Carbon and Nitrogen values were incorrectly added to the data sheet. A block of data was repeated for all treatments. In version 14 the values were corrected.
Physiological Ecology of Euryhaline Chironomid Midges in Cape Cod MA 2002-2003
In summer, 2002, hundreds of thousands of salt-tolerant midges (Chironomus decorus group, Diptera, Chironomidae) emerged from Pilgrim Lake/East Harbor, Truro, MA. The lake is a former estuary but has been separated from the sea for over 150 years by restrictions associated with railroad and highway construction. Brackish conditions caused by leaky tide gates designed to drain excess freshwater from the lake, coupled with high nutrient levels exacerbated by a massive fish kill the previous year, created conditions that supported densities of midge larvae of more than 5,000/m2 and produced a severe public nuisance in the vicinity of the lake when the adult midges emerged. The emergence coincided with National Park Service efforts to increase tidal flow into the lake, as part of a long-term commitment to restoration of restricted coastal waters within the Cape Cod National Seashore. We are studying the effects of increased tidal flow on midge populations, and in particular evaluating how high salinities need to be to reduce the potential for further nuisance outbreaks of the midges.
Little Rock Lake - CWH Study at North Temperate Lakes LTER - Benthic Macroinvertebrates 2002 - 2004
Benthic invertebrates were collected as part of CWH (coarse woody habitat) study on Little Rock Lake in Vilas county, WI. Pre-manipulation sampling of the macroinvertebrate communities was conducted in the summer of 2002 before the CWH reduction and six times after the reduction, in early, mid, and late summer (May-August) of 2003 and 2004. We divided the shoreline of Little Rock Lake into 50 m sections and randomly chose five sections from each basin for each separate sampling of macroinvertebrates. We collected two benthos and two CWH macroinvertebrate samples at each section. We constructed a benthos sampler by connecting a SCUBA tank to a 7.6 cm PVC pipe with a hose attached 10 cm from one end of the pipe (Wahle and Steneck 1991; Roth et al. 2007). A 500 m Nitex mesh bag was place at the top end of the pipe furthest from the attached hose. Once the tank was turned on, a vacuum formed that sucked the benthos sample into the bag. We used a 0.09 m2 hoop to delineate the benthos sampling area. We sampled CWH using a self-contained, battery-powered aquatic vacuum with a 500 m Nitex mesh bag (Vander Zanden et al. 2006). Sampling lasted for 30 seconds. All samples were stored in 95% ethanol until processed. Macroinvertebrates were identified to the lowest possible taxonomic level. Helmus M.R. and Sass G.G. (2008) The rapid effects of a whole-lake reduction of coarse woody debris on fish and benthic macroinvertebrates. Freshwater Biology, 53, 1423-1433 Number of sites: 44 Sampling Frequency: once pre-manipulation, 6 sampling regimes after reduction
North Temperate Lakes LTER: Summary of Microbial Activity 2000 - 2002
Summary of Microbial Observatory data from the bacterial production, planktonic respiration and alakline phosphatase activity databases, plus bacterial cell counts from epifluorescence microscopy using DAPI cell stain. Information on integrated sample depth and incubation temperature is also included Sampling Frequency: fortnightly during ice-free season - every 6 weeks during ice-covered season Number of sites: 4
Microbial Bacterial Production in Lakes at North Temperate Lakes LTER 2000 - 2002
Net production of bacteria passing a 70 micron mesh, or bacteria passing a 1 micron mesh, calculated incorporation of 3H labeled leucine into cell proteins. Method based on microcentrifuge method of Smith, David C., and Farooq Azam. 1992. A simple, economical method for measuring bacterial protein synthesis rates in seawater using 3H-leucine, Marine Microbial Food Webs 6(2):107-114. Nanomolar treatments refer to leucine concentration for calculation of isotopic dilution and necessary leucine concentration to saturate uptake into bacterial cells. For a good example on how to calculate isotopic dilution see Pace. Michael L., and Jonathan J. Cole. Primary and bacterial production in lakes: are they coupled over depth? Plankton Research 16(6):661-672. Sampling Frequency: fortnightly during ice-free season - every 6 weeks during ice-covered season Number of sites: 4
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.