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At least 1,009 records · Page 56Linked to original sources
USGS1970

Water resources data for Arizona, 1970: Part 1. Surface water records

Surface-water records for the 1970 water year for Arizona, including records of streamflow or reservoir storage at gaging stations. partial-record stations. and miscellaneous sites are given in this report and their locations shown in figures 1. 3, and 4. Records for a few pertinent gaging stations in bordering States also are included. The records were collected and computed by the Water Resources Division of the U. S. Geological Survey under the direction of H. M. Babcock, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Arizona. Through September 30, 1960, the records of discharge and stage of streams and canals and contents and stage of lakes or reservoirs were published in an annual series of U.S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States." Beginning with the 1961 water year, surface-water records have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. The discharge and reservoir storage records for 1961-65 also have been published in a Geological Survey water - supply paper series entitled "Surface Water Supply of the United States 1961-65."

Arizona↗
USGS1973

Water resources data for Arizona, water year 1972: Part 1. Surface water records

Surface-water records for the 1972 water year for Arizona, including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, are given in this report and their locations shown in figures 1, 3, and 4. Records for a few pertinent gaging stations in bordering States also are included, The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of H. M. Babcock, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Arizona. Through September 30, 1960, the records of discharge and stage of streams and canals and contents and stage of lakes or reservoirs were published in an annual series of U.S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States." Beginning with the 1961 water year, surface-water records have been released by the GeologicalSurvey in annual reports ona State-boundarybasis. Distribution of these reports islimited; theyare designed primarily for rapid release of data shortly after the end of the water year to meet local needs. The discharge and reservoir storage records for 1961-65 also have been published in a Geological Survey water - supply paper series entitled "Surface Water Supply ofthe United States 1961-65. "

Arizona↗
USGS1973

Water resources data for Arizona, water year 1972

Water resources data for the 1972 water year for Arizona include records of data for the chemical and physical characteristics of surface water. Data on the quality of surface water (chemical, temperature, and sediment) were collected from designated sampling sites at predetermined intervals, such as once daily, weekly, monthly, or less frequently; at some sites, data were collected continuously by means of automatic recording devices . Records are given for 77 sampling stations, of which 46 are continuous record stations, 8 are partial-record stations, and 23 are miscellaneous sampling stations. Locations of surface water-quality stations are shown in figures 1 and 2. A few pertinent stations in bordering States are also included. The records were collected by the Water Resources Division of the U.S. Geological Survey under the direction of H. M. Babcock, district chief. These data represent that portion of the National Water Data System collected bythe U.S. Geological Survey and cooperating State and Federal agencies in Arizona. The Geological Survey has published records of chemical quality, water temperatures, and sediment since 1941 in an annual s eries of water-supply papers entitled, ''Quality of Surface Waters of the United States." Beginning with the 1964 water year, water - quality records have been released by the Geological Survey in annual reports on a State boundary basis. These reports are for limited distribution and are designed primarily for rapid release of data shortly after the end of the water year. These records will be published later in Geological Survey water-supply papers.

Arizona↗
USGS1974

Water resources data for Arizona, water year 1973: Part 1. Surface water records

Surface-water records for the 1973 water year for Arizona, including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, are given in this report and their locations shown in figures 1, 3, and 4. Records for a few pertinent gaging stations in bordering States also are included. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of H. M. Babcock, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Arizona. Beginning with the 1961 water year, surface-water records have been released by the Geological Survey in annual reports on a State boundary basis. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. Records of discharge and stage of streams and canals and contents and stage of lakes and reservoirs are published in a series of U.S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States." Through September 30, 1960, these water-supply papers were in an annual series and since then are in a 5-year series. More information is given under the heading "Publications."

Arizona↗
USGS1974

Water resources data for Arizona, water year 1973: Part 2. Water quality records

Water resources data for the 1973 water year for Arizona include records of data for the chemical and physical characteristics of surface water. Data on the quality of surface water (chemical, temperature, and sediment) were collected from designated sampling sites at predetermined intervals, such as once daily, weekly, monthly, or less frequently; at some sites, data were collected continuously by means of automatic recording devices. Records are given for 81 sampling stations, of which 48 are continuous record stations, 6 are partial-record stations, and 27 are miscellaneous sampling stations. Locations of surface water-quality stations are shown in figures 1 and 2. A few pertinent stations in bordering States are also included. The records were collected by the Water Resources Division of the U.S. Geological Survey under the direction of H. M. Babcock, district chief. These data represent that portion of the National Water Data System collected by the U. S. Geological Survey and cooperating State and Federal agencies in Arizona. The Geological Survey has published records of chemical quality, water temperatures, and sediment since 1941 in an annual series of water-supply papers entitled, "Quality of Surface Waters of the United States." Beginning with the 1964 water year, water-quality records have been released by the Geological Survey in annual reports on a State boundary basis. These reports are for limited distribution and are designed primarily for rapid release of data shortly after the end of the water year. These records will be published later in Geological Survey water-supply papers.

Arizona↗
USGS1972

Water resources data for Kansas, water year 1971; Part 2, Water quality records

Water-resources data for the 1971 water year for Kansas include records of data for the chemical and physical characteristics of surface and ground water. Data on the quality of surface water (chemical, microbiological, temperature, and sediment) were collected from designated sampling sites at predetermined intervals such as once daily, weekly, monthly, or less frequently. Records are given for 66 sampling stations of which 9 are partial-record stations, and 52 are miscellaneous sites. Records of chemical analyses are given for 46 ground-water sites. Locations of surface water-quality stations are shown in Figure 1, page 2. Records for pertinent water-quality stations in bordering States are also included. The records were collected by the Water Resources Division of the U.S. Geological Survey under the direction of C. W. Lane, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Kansas. The Geological Survey has published records of chemical quality, suspended sediment, and water temperatures since 1941 in annual series of water-supply papers entitled, "Quality of Surface Waters of the United States." Beginning with the 1964 water year, water-quality records also have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. These records will be published later in Geological Survey water-supply papers.

Kansas↗
USGS1973

Water resources data for Kansas, water year 1972; Part 1, Surface water records

Surface-water records for the 1972 water year for Kansas, including records of streamflow or reservoir storage at gaging stations and partial-record stations, are given in this report. The locations of the stations are on figures 1 and 2. Records for a few pertinent gaging stations in bordering States also are included. These data represent that part of the National Water Data System collected by the U. S. Geological Survey and cooperating State and Federal agencies in Kansas. The records were collected and computed by the Water Resources Division of the U. S. Geological Survey under the direction of C. W. Lane, district chief. Kansas district personnel who contributed significantly to the collection and preparation of data included in this report were: J. L. Ebling, C. 0. Geiger, K. D. Medina, L. E. Stuliken, C. 0. Peek, J. D. Craig, L. L. Jones, A. T. Klamm, J. P. Marshall, C. W. Kennedy, W. J. Carswell, D. L. Lacock, G. G. Quy II, J. T. Religa, R. D. Thomas, S. V. Bond, S. T. Green, C. G. Sauer, A. B. Evans, A. F. Browning, M. J. Goetz, M. L. Penny, and M. Pabst. Through September 30, 1960, the records of discharge and stage of streams and canals and contents and stage of lakes or reservoirs were published in an annual series of U. S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States." Beginning with the 1961 water year, surface-water records have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. The discharge and reservoir storage records for 1961-65 also have been published in a Geological Survey water-supply paper series entitled "Surface Water Supply of the United States 1961-65."

Kansas↗
USGS2000

Water Resources Data Massachusetts and Rhode Island Water Year 1999

INTRODUCTION The Water Resources Division of the U.S. Geological Survey, in cooperation with State agencies, obtains a large amount of data pertaining to the water resources of Massachusetts and Rhode Island each water year. These data, accumulated during many water years, constitute a valuable data base for developing an improved understanding of the water resources of the States. To make these data readily available to interested parties outside the Geological Survey, the data are published annually in this report series entitled 'Water Resources Data-Massachusetts and Rhode Island.' Hydrologic data are also available through the Massachusetts-Rhode Island District Home Page on the world-wide web (http://ma.water.usgs.gov). Historical data and real-time data (for sites equipped with satellite gage-height telemeter) are also available. The home page also contains a link to the U.S. Geological Survey National Home Page where streamflow data from locations throughout the United States can be retrieved. This report series includes records of stage, discharge, and water quality of streams; contents of lakes and reservoirs; water levels of ground-water wells; and water quality of ground-water wells. This volume contains discharge records at 90 gaging stations; stage records at 2 gaging stations; monthend contents of 4 lakes and reservoirs; water quality at 31 gaging stations; water quality at 27 observation wells; and water levels for 139 observation wells. Locations of these sites are shown in figures 1 and 2. Short-term water-quality data were collected at 21 gaging stations and 27 observation wells and are shown in figure 3. Miscellaneous hydrologic data were collected at various sites that were not involved in the systematic data-collection program and are published as miscellaneous discharge measurements. The data in this report represent that part of the National Water Data System operated by the U.S. Geological Survey and cooperating State and Federal agencies in Massachusetts and Rhode Island. This series of annual reports for Massachusetts and Rhode Island began with the 1961 water year with a report that contained only data relating to the quantities of surface water. For the 1964 water year, a similar report was introduced that contained only data relating to water quality. Beginning with the 1975 water year, the report format was changed to present, in one volume, data on quantities of surface water, quality of surface and ground water, and ground-water levels. Prior to introduction of this series and for several water years concurrent with it, water-resources data for Massachusetts and Rhode Island were published in U.S. Geological Survey Water-Supply Papers. Data on stream discharge and stage and on lake or reservoir contents and stage, through September 1960, were published annually under the title 'Surface-Water Supply of the United States, Parts 1A and 1B.' For the 1961 through 1970 water years, the data were published in two 5-year reports. Data on chemical quality, temperature, and suspended sediment for the 1941 through 1970 water years were published annually under the title 'Quality of Surface Waters of the United States,' and water levels for the 1939 through 1974 water years were published under the title 'Ground-Water Levels in the United States.' The above mentioned Water-Supply Papers may be consulted in the libraries of the principal cities of the United States and may be purchased from U.S. Geological Survey, Information Services, Box 25286, Denver Federal Center, Box 25425, Denver, CO 80225-0286. Publications similar to this report are published annually by the Geological Survey for all States. These official Survey reports have an identification number consisting of the two-letter State abbreviation, the last two digits of the water year, and the volume number. For example, this volume is identified as 'U.S. Geological Survey Water-Data Report MARI-98-1.' For archiving and general d

Water Data Report↗
USGS1973

Water resources data for Michigan, water year 1972; Part 1, Surface water records

Surface-water records for the 1972 water year for gaging stations, partial-record stations, and miscellaneous sites within the State of Michigan are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering States. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey, under the direction of T. R. Cummings, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Michigan. Records of discharge and stage of streams, and contents and stage of lakes or reservoirs are published in a series of U.S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States". Through September 30, 1960, these water-supply papers were in an annual series and since then are in a 5-year series. Since 1951 there have been 20 volumes in the series; each volume covered an area whose boundaries coincided with those of certain natural drainage areas. The records in Michigan were contained in Part 4 of that series. Beginning with the 1961 water year, streamflow records and related data have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these basic-data reports is limited and primarily for local needs.

Michigan↗
USGS1974

Water resources data for Michigan, water year 1973; Part 1, Surface water records

Surface-water records for the 1973 water year for gaging stations, partial-record stations, and miscellaneous sites within the State of Michigan are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering States. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey, under the direction of T.R. Cummings, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Michigan. Records of discharge and stage of streams, and contents and stage of lakes or reservoirs are published in a series of U.S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States". Through September 30, 1960, these water-supply papers were in an annual series and since then are in a 5-year series. Since 1951 there have been 20 volumes in the series; each volume covered an area whose boundaries coincided with those of certain natural drainage areas. The records in Michigan are contained in Part 4 of that series. Beginning with the 1961 water year, streamflow records and related data have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these basic-data reports is limited and primarily for local needs.

Michigan↗
USGS1975

Water resources data for Michigan, water year 1974; Part 1, Surface water records

Surface-water records for the 1974 water year for gaging stations, partial-record stations, and miscellaneous sites within the State of Michigan are given in this report. For convenience there are also included records for a few pertinent gaging stations in bordering States. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey, under the direction of T.R. Cummings, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Michigan. Records of discharge and stage of streams, and contents and stage of lakes or reservoirs are published in a series of U.S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States". Through September 30, 1960, these water-supply papers were in an annual series and since then are in a 5-year series. Since 1951 there have been 20 volumes in the series; each volume covered an area whose boundaries coincided with those of certain natural drainage areas. The records in Michigan are contained in Part 4 of that series. Beginning with the 1961 water year, streamflow records and related data have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these basic-data reports is limited and they are designed primarily for rapid release of data shortly after the end of the water year.

Michigan↗
USGS1970

Water resources data for New Mexico, water year 1969; Part 1. Surface water records

Surface-water records for the 1969 water year for New Mexico, including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, are given in this report and their locations shown in figures 1, 2. Records for a few pertinent gaging stations in bordering states also are included. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of W. E. Hale, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in New Mexico. Through September 30, 1960, the records of discharge and stage of streams and canals and contents and stage of lakes or reservoirs were published in an annual series of U.S. Geological Survey water-supply papers entitled Surface Water Supply of the United States." Beginning with the 1961 water year, surface-water records have been released by the Geological Survey in annual reports on a State-boundary basis. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. The discharge and reservoir storage records for 1961-65 also will be published in a Geological Survey water-supply paper series entitled "Surface Water Supply of the United States 1961-65."

New Mexico↗
USGS1975

Water resources data for New Mexico, water year 1974; Part 1, Surface water records

Surface-water records for the 1974 calendar year for New Mexico, including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, are given in this report and their locations shown in figures 1, 2. Records for a few pertinent gaging stations in bordering States also are included. The records were collected and computed by the Water Resources Division of the U.S, Geological Survey under the direction of W. E. Hale, district chief. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in New Mexico. Records of discharge and stage of streams, and contents and stage of lakes and reservoirs are published in a series of U.S. Geological Survey water-supply papers entitled, "Surface Water Supply of the United States." Through September 30, 1960, these water-supply papers were in an annual series, and since then, are in a 5-year series. More information is given under heading, "Publications" on page 8. Beginning with the 1961 water year, surface-water records have been released by the Geological Survey in annual reports on a State boundary basis. Distribution of these reports is limited; they are designed primarily for rapid release of data shortly after the end of the water year to meet local needs. Beginning with the 1971 calendar year, surface water records have been released on a calendar year basis.

New Mexico↗
USGS1974

Water resources data for Wyoming, water year 1973; part 1, surface water records

Surface-water records for the 1973 water year for Wyoming, including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, are given in this report. The locations of the gaging stations and partial-record stations are shown in figures 1 and 2. Records for a few pertinent gaging stations in bordering States also are included. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Wyoming. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Robert L. Cushman, district chief. Wyoming district personnel who contributed significantly to the collection and preparation of data included in this report were: S.A. Druse, D. J. O'Connell, G. S. Craig, Jr., G. W. Armentrout, Jr., H. W. Lowham, J. G. Rankl, P. B. McCollam, C. F. Obert, W. R. Glass, T.W. Custis, R. L. Muench, J. O. Ragsdale, M. D. Stevens, R. C. Bauman, J. L. Lynch, and S. L. Green. Beginning with the 1961 water year, streamflow records and related data have been released by the Geological Survey in annual reports on a State-boundary basis. These reports are for limited distribution and are designed primarily for rapid release of data shortly after the end of the water year. Records of discharge and stage of streams and canals, and contents and stage of lakes or reservoirs, are published in a series of U.S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States." Through September 30, 1960, these water-supply papers were in an annual series and since then are in a 5-year series. More information is given under the heading "Publications" on page 9.

Wyoming↗
USGS1975

Water resources data for Wyoming, water year 1974

Surface-water records for the 1974 water year for Wyoming, including records of streamflow or reservoir storage at gaging stations, partial-record stations, and miscellaneous sites, are given in this report. The locations of the gaging stations and partial-record stations are shown in figures 1 and 2. Records for a few pertinent gaging stations in bordering States also are included. These data represent that portion of the National Water Data System collected by the U.S. Geological Survey and cooperating State and Federal agencies in Wyoming. The records were collected and computed by the Water Resources Division of the U.S. Geological Survey under the direction of Sam W. West, district chief. Wyoming district personnel who contributed significantly to the collection and preparation of data included in this report were: S. A. Druse, D. J. O'Connell, G. S. Craig, Jr., G. W. Armentrout, Jr., H. W. Lowham, J. G. Rankl, P. B. McCollam, C. F. Obert, W. R. Glass, D. J. Pangburn, T. W. Custis, R. L. Muench, J. O. Ragsdale, M. D. Stevens, R. C. Bauman, D. J. Wangsness, L. W. Lenfest, B. C. Pedersen, M. T. O'Grady, and S. L. Green. Beginning with the 1961 water year, streamflow records and related data have been released by the Geological Survey in annual reports on a State-boundary basis. These reports are for limited distribution and are designed primarily for rapid release of data shortly after the end of the water year. Records of discharge and stage of streams and canals, and contents and stage of lakes or reservoirs, are published in a series of U.S. Geological Survey water-supply papers entitled "Surface Water Supply of the United States." Through September 30, 1960, these water-supply papers were in an annual series and since then are in a 5-year series. More information is given under the heading "Publications" on page 9.

Wyoming↗
USGS1990

Comparison of accuracy and completeness of data obtained from three types of automatic water-quality monitors

A comparison of data (specific conductance, dissolved-oxygen concentration, temperature, and pH) collected by the U.S. Geological Survey flowthrough monitor, the U.S. Geological Survey minimonitor, and a self-contained commercial 'packaged-sensor' system indicates that the data obtained by means of the most complete of the three systems. The U.S. Geological Survey flowthrough monitor is powered by 120-volt alternating current and in a heated weather-proof shelter. A pumping system brings water from the stream to sensors clustered in a sample clustered in a sample chamber located in the shelter. This instrument measures output from the senors; data are recorded in binary-coded decimal form on a 16-channel punched-paper tape recorder tape recorder housed in the shelter. The U.S. Geological Survey's minimonitor is powered by an external battery and is housed in a weatherproof shelter. This instrument measures output of instream sensors with extension cables having underwater connectors; data are recorded in binary-coded decimal form on a 16-channel punched-paper tape recorder housed in the shelter. The packaged-sensor system also measures output of senors housed in a packages that is submerged in the stream. It has internal power supply, no moving parts, and does not requires a weatherproof shelter; data are stored are stored in solid-state memory. Minimonitors were installed at four sites in Ohio where U.S. Geological survey flowthrough were in operation. Two package-sensor systems also were assigned to each site and were alternated every two weeks. Detailed records were kept of (1) field measurements, for comparison with monitor-system data from each instrument, and (2) equipment problems that resulted in loss of data. Results of the comparisons shows that the flow-through monitor gave the most accurate and the most complete data.

Water-Resources Investigations Report↗
USGS2019

Growing pains of crowdsourced stream stage monitoring using mobile phones: The development of CrowdHydrology

Citizen science-based approaches to monitor the natural environment tend to be bimodal in maturity. Older and established programs such as the Audubon’s Christmas bird count and Community Collaborative Rain, Hail, and Snow Network (CoCoRaHS) have thousands of participants across decades of observations, while less mature citizen science projects have shorter lifespans often focused on local or regional observations with tens or hundreds of participants. For the latter, it can be difficult to transition into a more mature and sustainable citizen science-based research program. This paper focuses on this transition by evaluating CrowdHydrology (ca. 2010), a citizen science project that has transitioned from a regional to national network. It evaluates the data accuracy, citizen participation, and station popularity. The CrowdHydrology network asks citizens to send in text messages of water levels in streams and lakes, which has resulted in 16,294 observations submitted by over 8,000 unique participants at 120 unique locations. Using water level data and participation records from CrowdHydrology, we analyze the expansion and citizen participation from a regional to national citizen science network. We identify barriers to participation and evaluate why some citizen science observation stations are popular while others are not. We explore our chosen contributory program model for CrowdHydrology and the influence this model has had on long-term participation. Results demonstrate a highly variable rate of contributions of citizen scientists. This paper proposes hypotheses on why many of our observations are from one-time participants and why some monitoring stations are more popular than others. Finally, we address the future expansion of the CrowdHydrology network by evaluating successful monitoring locations and growing interest of watershed groups to expand the network of gauges.

Frontiers in Earth Science↗
USGS2020

The elephant in the lab (and field): Contamination in aquatic environmental DNA studies

The rapid evolution of environmental (e)DNA methods has resulted in knowledge gaps in smaller, yet critical details like proper use of negative controls to detect contamination. Detecting contamination is vital for confident use of eDNA results in decision-making. We conducted two literature reviews to summarize (a) the types of quality assurance measures taken to detect contamination of eDNA samples from aquatic environments, (b) the occurrence, frequency and attribution (i.e., putative sources) of unexpected amplification in these quality assurance samples, and (c) how results were interpreted when contamination occurred. In the first literature review, we reviewed 156 papers and found that 91% of targeted and 73% of metabarcoding eDNA studies reported inclusion of negative controls within their workflows. However, a large percentage of targeted (49%) and metabarcoding (80%) studies only reported negative controls for laboratory procedures, so results were potentially blind to field contamination. Many of the 156 studies did not provide critical methodological information and amplification results of negative controls. In our second literature review, we reviewed 695 papers and found that 30 targeted and 32 metabarcoding eDNA studies reported amplification of negative controls. This amplification occurred at similar proportions for field and lab workflow steps in targeted and metabarcoding studies. These studies most frequently used amplified negative controls to delimit a detection threshold above which is considered significant or provided rationale for why the unexpected amplifications did not affect results. In summary, we found that there has been minimal convergence over time on negative control implementation, methods, and interpretation, which suggests that increased rigor in these smaller, yet critical details remains an outstanding need. We conclude our review by highlighting several studies that have developed especially effective quality assurance, control and mitigation methods.

Frontiers in Ecology and Evolution↗