Periphyton is a complex community of detritus, bacteria, fungi, and algae that grows attached to submerged substrates. Assemblage structure data for algae and cyanobacteria from periphyton samples were collected on a monthly basis from 2017 to 2021. Compiled data were reported as absolute abundance (cells) and biovolume per volume as well as absolute abundance (cells) and biovolume per area at four locations increasing in distance East of the L-67 canal in Water Conservation Area 3 (WCA 3) of the Florida Everglades immediately north of Everglades National Park. The periphyton assemblages were analyzed for five sample types including periphyton plates (Plates), invertebrate inclusion and exclusion plates (Inverts), biological oxygen demand cores (BOD), vertical/sediment traps (VertSedTrap), and metaphyton cores (MetaCore).

A data package consisting of diatom, total phosphorus, and related data collected in Big Cypress National Preserve as part of the SFCN Periphyton Vital Signs protocol. Periphyton is a microbial mat community that forms the base of the aquatic food web in South Florida wetlands such as the marshes in Everglades National Park (EVER) and the Big Cypress National Preserve (BICY). It is a vital component of these wetlands, contributing to critical functions such as primary production, nutrient cycling, and soil production and stabilization. Periphyton is sensitive to changes in hydropattern (water quantity and duration) and water quality. Changes to these ecosystem processes can quickly alter periphyton community structure (species composition and relative abundance), which in turn can create cascading effects through higher trophic levels. Thus, periphyton is an early and integrative indicator of local and regional changes to hydrology. The South Florida/Caribbean Network has implemented the monitoring of periphyton communities in Big Cypress National Preserve to assess the impact of hydrologic and water quality changes on the diatom community structure and total phosphorous (TP) concentrations of the periphyton mats. The specific monitoring objectives are: 1) Identify any basins in the northwest section of Big Cypress National Preserve where periphyton community structure and periphyton TP content are different from an oligotrophic (low-nutrient) and unimpacted community signal. 2) Document any temporal and/or spatial changes in the periphyton community structure and periphyton TP content showing progression towards an oligotrophic, unimpacted condition or a eutrophic (high-nutrient), impacted condition. This dataset includes all data collected (both pilot and standard) between 2008 and 2025. 2025 sites are listed in this release alongside their field data, but lab results have yet to be received for these sites at this time.

This data release contains a 17-year record (2005-2022) of discrete chlorophyll data from inland waters, collected from across the nation and territories. These data are from discrete samples (collected in the field and analyzed in the laboratory) from plankton (suspended algae) and periphyton (benthic algae) from lakes, streams, rivers, reservoirs, canals, and other sites. These data are gathered to support process and remote sensing modeling and prediction of Harmful Algal Blooms (HABs). The chlorophyll data were compiled from the Water Quality Portal (WQP) and USGS National Water Quality Lab (NWQL).

Data for uncorrected chlorophyll a, corrected chlorophyll a, and pheophytin from EPA Methods 445 and 446 are included and reported, following the conventions of EPA section 445:

• 12.1 uncorrected chlorophyll a – based on the initial optical measurement of the sample, which includes both chlorophyll a and pheophytin
• 12.2 corrected chlorophyll a – based on optical measurement after acidification and calculation to estimate the amount of active chlorophyll in the original sample
• 12.3 pheophytin – based on calculations to estimate the amount of pheophytin in the original sample

These data were harmonized for reporting units (plankton as µg/L and periphyton as mg/m2), duplicate values, collection depth, site type, negative values, and some extreme values. HABs events are associated with high values of chlorophyll, as algae may be concentrated in dense surface scums. These data may include an indicator for hydrologic event code, which may be helpful in determining HABs events.

Acknowledgements

This work was completed as part of two projects in the USGS Water Mission Area (WMA) Water Quality Processes Program: (1) the Improved Understanding and Prediction of Prioritized Constituents Project, an effort to advance datasets and understanding of chlorophyll, nutrient, carbon, and sediment occurrence and transport, and (2) the Proxies Project, an effort to develop estimation methods for PFAS, harmful algal blooms, and metals, at multiple spatial and temporal scales.

Arar, E.J. and Collins, G.B. 1997. Method 445.0: In vitro determination of chlorophyll a and pheophytin a in marine and freshwater algae by fluorescence. EPA Office of Research and Development.

Spatial reconnaissance of fluvial microcystins (MC) concentrations and select water-quality parameters, including nutrients and periphyton biomass, in 75 wadeable streams in the Piedmont region of the southeastern USA during 2014. Data set includes only those data specifically discussed in the associated journal article: Loftin, K.A., Clark, J.M., Journey, C.A., Kolpin, D.W., Van Metre, P.C., and Bradley, P.M., 2016, Spatial and temporal variation in microcystins occurrence in wadeable streams in the southeastern USA: Environmental Toxicology and Chemistry, http://dx.doi.org/10.1002/etc.3391.

This part of the data release contains the water-use withdrawal data in the Permian Basin in Texas aggregated by county for the categories of irrigation, livestock, mining, and domestic. These digital data accompany Valder, J.F., McShane, R.R., Thamke, J.N., McDowell, J.S., Ball, G.P, Houston, N.A., and Galanter, A.E., Estimates of Water Use Associated with Continuous Oil and Gas Development in the Permian Basin, Texas and New Mexico, 1980–2019, https://doi.org/10.3133/sir20215090.

The data are species counts by location, as well as other environmental variables for each stream location sampled. This dataset is associated with the following publication: Stamp, J., A. Moore, S. Fiske, J. Gerritsen, B. Bierwagen, and A. Hamilton. Effects of Extreme High Flow Events on Macroinvertebrate Communities in Vermont Streams. River Research and Applications. John Wiley & Sons Incorporated, New York, NY, USA, 36(9): 1891-1902, (2020).

Hydrographic and Impairment Statistics (HIS) is a National Park Service (NPS) Water Resources Division (WRD) project established to track certain goals created in response to the Government Performance and Results Act of 1993 (GPRA). One water resources management goal established by the Department of the Interior under GRPA requires NPS to track the percent of its managed surface waters that are meeting Clean Water Act (CWA) water quality standards. This goal requires an accurate inventory that spatially quantifies the surface water hydrography that each bureau manages and a procedure to determine and track which waterbodies are or are not meeting water quality standards as outlined by Section 303(d) of the CWA. This project helps meet this DOI GRPA goal by inventorying and monitoring in a geographic information system for the NPS: (1) CWA 303(d) quality impaired waters and causes; and (2) hydrographic statistics based on the United States Geological Survey (USGS) National Hydrography Dataset (NHD). Hydrographic and 303(d) impairment statistics were evaluated based on a combination of 1:24,000 (NHD) and finer scale data (frequently provided by state GIS layers).

Hydrographic and Impairment Statistics (HIS) is a National Park Service (NPS) Water Resources Division (WRD) project established to track certain goals created in response to the Government Performance and Results Act of 1993 (GPRA). One water resources management goal established by the Department of the Interior under GRPA requires NPS to track the percent of its managed surface waters that are meeting Clean Water Act (CWA) water quality standards. This goal requires an accurate inventory that spatially quantifies the surface water hydrography that each bureau manages and a procedure to determine and track which waterbodies are or are not meeting water quality standards as outlined by Section 303(d) of the CWA. This project helps meet this DOI GRPA goal by inventorying and monitoring in a geographic information system for the NPS: (1) CWA 303(d) quality impaired waters and causes; and (2) hydrographic statistics based on the United States Geological Survey (USGS) National Hydrography Dataset (NHD). Hydrographic and 303(d) impairment statistics were evaluated based on a combination of 1:24,000 (NHD) and finer scale data (frequently provided by state GIS layers).

The U.S. Geological Survey is studying uranium and associated trace element bioaccumulation in aquatic invertebrates across a gradient of dissolved uranium concentrations in spring outflow pools and creeks in the Grand Canyon and adjacent watershed. This data release makes available data from sampling campaigns in April 2016, April 2017, and April 2019. Data collected include: (1) major ion, trace element and dissolved organic carbon in surface waters of spring outflow pools and streams; (2) concentrations of uranium and other trace elements in bed sediment, periphyton, and larva of aquatic insect taxa; (3) uranium and iron extraction data from a subset of bed sediment samples, and (4) X-ray diffraction data for bed sediment samples collected in 2019. This dataset includes samples from the corrected original data release (invertebrate data for 2016 were incorrectly reported as mass concentrations (mg/kg) in the original csv file), plus samples collected in 2019. NOTE: While previous versions are available from the author, all the records in previous versions can be found in version 4.0. Direct questions regarding data to the authors.