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At least 19 recordsLinked to original sources
USGS1997

Characterization of springflow in the north coast limestone of Puerto Rico using physical, chemical, and stable isotopic methods

The carbonate sequence of middle Tertiary age of the north coast of Puerto Rico is characterized by the presence of numerous springs in the coastal areas. In order to advance the understanding of the hydrologic role of the springs in the north coast limestone aquifer system of Puerto Rico, a 4-year study was conducted by the U.S. Geological Survey in cooperation with the Puerto Rico Aqueduct and Sewer Authority. As part of this study, data were collected on the chemical, physical, bacteriological, oxygen-18, and deuterium composition of water from springs in the Dorado to Rincon area, in northwestern Puerto Rico. A group of springs in the Dorado to Arecibo area was selected for more detailed monitoring. Oxygen-18 and deuterium composition was also determined for water wells and monthly rainfall composites at a series of sites in the study area. Springs are associated with all the carbonate units of the middle Tertiary sequence of the northern karst belt of Puerto Rico, except the Camuy and San Sebastian Formations. These springs mostly drain the unconfined parts of the upper and lower aquifers in the north coast limestone aquifer system. There are no first and second order springs in the north coast limestone and of those present fifth and sixth order springs are the most numerous type. Springflow at the springs measured during the study ranged from less than 0.1 to 61 cubic feet per second. Springs in the north coast limestone can also be classified by their response to rainfall. There is little or no short-term response to rainfall at springs such as Ojo de Agua in Vega Baja, Mameyes in Manati, and Mackovic in Vega Alta. These springs are known as diffuse-type springs. Other springs such as Maguayo in Dorado, Ojo de Guillo in Manati, and San Pedro in Arecibo exhibit a strong short-term response to rainfall and are known as conduit-type springs. Spring water temperature, during the study, ranged from 22.5 to 28 °C and resembled air temperature. Specific conductance ranged from 289 to about 4,000 microsiemens per centimeter, and pH ranged from 6.9 to 7.8. Calcium, sodium, bicarbonate, and chloride are the main ionic species in water from the springs sampled during the study. The main water type is calcium-bicarbonate and secondary water types are calcium-bicarbonate chloride and sodium-bicarbonate-chloride. A seasonal and short-term transient relation exists, particularly in conduit-type springs, between springflow, physical properties, and water quality. Temporal and spatial variations in the oxygen-18 and deuterium composition of modern precipitation are significantly larger than those of springs and ground water in the study area. Regional flow in the upper aquifer appears to attenuate or average the variations in isotopic composition of rainfall. There is, however, a regional gradient in the deuterium composition of water from the upper aquifer in the north coast limestone, with isotopically heavier water occurring further north. It was possible to determine the source of water contributing to springs at some sites with more detailed data collection and analysis. A drainage basin of about 10 square kilometers was delineated for the Ojo de Agua spring in Vega Baja, for a base flow of 2 cubic feet per second and an estimated subregional recharge rate of around 20 inches per year. A delineation of drainage basins for conduit-type springs in the study area such as San Pedro, Ojo de Guillo, Maguayo, and others is very difficult because the boundaries of these systems are highly responsive to changing hydraulic conditions such as rapid and short-term variations in the hydraulic head distribution as a consequence of rainfall. However, a preliminary drainage basin of about 6 square kilometers was delineated for the San Pedro spring for a base flow of 2 cubic feet per second and an estimated subregional annual recharge of 12 inches.

Puerto Rico↗
USGS2009

Effects of urbanization on the chemical, physical, and biological characteristics of small Blackland Prairie streams in and near the Dallas-Fort Worth metropolitan area, Texas

In 2001, the U.S. Geological Survey National Water Quality Assessment Program began a series of studies in the contiguous United States to examine the effects of urbanization on the chemical, physical, and biological characteristics of streams. Small streams in the Texas Blackland Prairie level III ecoregion in and near the Dallas-Fort Worth metropolitan area were the focus of one of the studies. The principal objectives of the study, based on data collected in 2003-04 from 28 subbasins of the Trinity River Basin, were to (1) define a gradient of urbanization for small Blackland Prairie streams in the Trinity River Basin on the basis of a range of urban intensity indexes (UIIs) calculated using land-use/land-cover, infrastructure, and socioeconomic characteristics; (2) assess the relation between this gradient of urbanization and the chemical, physical, and biological characteristics of these streams; and (3) evaluate the type of relation (that is, linear or nonlinear, and whether there was a threshold response) of the chemical, physical, and biological characteristics of these streams to the gradient of urbanization. Of 94 water-chemistry variables and one measure of potential toxicity from a bioassay, the concentrations of two pesticides (diazinon and sima-zine) and one measure of potential toxicity (P450RGS assay) from compounds sequestered in semipermeable membrane devices were significantly positively correlated with the UII. No threshold responses to the UII for diazinon and simazine concentrations were observed over the entire range of the UII scores. The linear correlation for diazinon with the UII was significant, but the linear correlation for simazine with the UII was not. No statistically significant relations between the UII and concentrations of suspended sediment, total nitrogen, total phosphorous, or any major ions were indicated. Eleven of 59 physical variables from streamflow were significantly correlated with the UII. Temperature was not significantly correlated with the UII, and none of the physical habitat measurements were significantly correlated with the UII. Seven physical variables categorized as streamflow flashiness metrics were significantly positively correlated with the UII, two of which showed a linear but not a threshold response to the UII. Four flow-duration metrics were significantly negatively correlated with the UII, of which two showed a linear response to the UII, one showed a threshold response, and one showed neither. None of the fish metrics were significantly correlated with the UII in the Blackland Prairie streams. Two qualitative multi-habitat benthic macroinvertebrate metrics, predator richness and percentage filterer-collector richness, were significantly correlated with the UII; predator richness was negatively correlated with the UII, and percentage filterer-collector richness was positively correlated with the UII. No threshold response to the UII was observed for either metric, but both showed a significant linear response to the UII. Three richest targeted habitat (RTH) benthic macroinvertebrate metrics, Margalef's richness, predator richness, and omnivore richness were significantly negatively correlated with the UII. Margalef's richness was the only RTH metric that indicated a threshold response to the UII. The majority of unique taxa collected in the periphytic algae samples were diatoms. Six RTH periphytic algae metrics were correlated with the UII and five of the six showed no notable threshold response to the UII; but all five showed significant linear responses to the UII. Only the metric OT_VL_DP, which indicates the presence of algae that are tolerant of low dissolved oxygen conditions, showed a threshold response to the UII. Six depositional target habitat periphytic algae metrics were correlated with the UII, five of which showed no threshold response to the UII; three of the five showed significant linear responses to the UII, one showed a borderline significant

Texas↗
USGS2007

Selected Physical, Chemical, and Biological Data for 30 Urbanizing Streams in the North Carolina Piedmont Ecoregion, 2002-2003

This report provides summarized physical, chemical, and biological data collected during a study of the effects of urbanization on stream ecosystems as part of the U.S. Geological Survey's National Water-Quality Assessment study. The purpose of this study was to examine differences in biological, chemical, and physical characteristics of streams across a gradient of urban intensity. Thirty sites were selected along an urbanization gradient that represents conditions in the North Carolina Piedmont ecoregion, including the cities of Raleigh, Durham, Cary, Greensboro, Winston-Salem, High Point, Asheboro, and Oxford. Data collected included streamflow variability, stream temperature, instream chemistry, instream aquatic habitat, and collections of the algal, macroinvertebrate, and fish communities. In addition, ancillary data describing land use, socioeconomic conditions, and urban infrastructure were compiled for each basin using a geographic information system analysis. All data were processed and summarized for analytical use and are presented in downloadable data tables, along with the methods of data collection and processing.

North Carolina↗
USGS2001

Statistical summary of selected physical, chemical, and toxicity characteristics and estimates of annual constituent loads in urban stormwater, Maricopa County, Arizona

Stormwater and streamflow in Maricopa County were monitored to (1) describe the physical, chemical, and toxicity characteristics of stormwater from areas having different land uses, (2) describe the physical, chemical, and toxicity characteristics of streamflow from areas that receive urban stormwater, and (3) estimate constituent loads in stormwater. Urban stormwater and streamflow had similar ranges in most constituent concentrations. The mean concentration of dissolved solids in urban stormwater was lower than in streamflow from the Salt River and Indian Bend Wash. Urban stormwater, however, had a greater chemical oxygen demand and higher concentrations of most nutrients. Mean seasonal loads and mean annual loads of 11 constituents and volumes of runoff were estimated for municipalities in the metropolitan Phoenix area, Arizona, by adjusting regional regression equations of loads. This adjustment procedure uses the original regional regression equation and additional explanatory variables that were not included in the original equation. The adjusted equations had standard errors that ranged from 161 to 196 percent. The large standard errors of the prediction result from the large variability of the constituent concentration data used in the regression analysis. Adjustment procedures produced unsatisfactory results for nine of the regressions?suspended solids, dissolved solids, total phosphorus, dissolved phosphorus, total recoverable cadmium, total recoverable copper, total recoverable lead, total recoverable zinc, and storm runoff. These equations had no consistent direction of bias and no other additional explanatory variables correlated with the observed loads. A stepwise-multiple regression or a three-variable regression (total storm rainfall, drainage area, and impervious area) and local data were used to develop local regression equations for these nine constituents. These equations had standard errors from 15 to 183 percent.

Arizona↗
USGS2013

Physical, chemical, and isotopic data from groundwater in the watershed of Mirror Lake, and in the vicinity of Hubbard Brook, near West Thornton, New Hampshire, 1983 to 1997

Research on the hydrogeologic setting of Mirror Lake near West Thornton, New Hampshire (43° 56.5’ N, 71° 41.5’ W), includes the study of the physical, chemical, and isotopic characteristics of groundwater in the vicinity of the lake and nearby Hubbard Brook. Presented here are those physical, chemical, and isotopic data for the period 1983 to 1997. Data were collected from observation wells installed in glacial drift and bedrock, as well as from one domestic well in the general area of the lake and Hubbard Brook. Also presented are data for Mirror Lake for August 1, 1993, to place groundwater data in context with chemical and isotopic characteristics of the lake.

New Hampshire↗
USGS2007

Chapter B. Physical, Chemical, and Biological Responses of Streams to Increasing Watershed Urbanization in the Piedmont Ecoregion of Georgia and Alabama, 2003

As part of the U.S. Geological Survey National Water-Quality Assessment Program?s effort to assess the physical, chemical, and biological responses of streams to urbanization, 30 wadable streams were sampled near Atlanta, Ga., during 2002?2003. Watersheds were selected to minimize natural factors such as geology, altitude, and climate while representing a range of urban development. A multimetric urban intensity index was calculated using watershed land use, land cover, infrastructure, and socioeconomic variables that are highly correlated with population density. The index was used to select sites along a gradient from low to high urban intensity. Response variables measured include stream hydrology and water temperature, instream habitat, field properties (pH, conductivity, dissolved oxygen, turbidity), nutrients, pesticides, suspended sediment, sulfate, chloride, Escherichia coli (E. coli) concentrations, and characterization of algal, invertebrate and fish communities. In addition, semipermeablemembrane devices (SPMDs)?passive samplers that concentrate hydrophobic organic contaminants such as polycyclicaromatic hydrocarbons (PAHs)?were used to evaluate water-quality conditions during the 4 weeks prior to biological sampling. Changes in physical, chemical, and biological conditions were evaluated using both nonparametric correlation analysis and nonmetric multidimensional scaling (MDS) ordinations and associated comparisons of dataset similarity matrices. Many of the commonly reported effects of watershed urbanization on streams were observed in this study, such as altered hydrology and increases in some chemical constituent levels. Analysis of water-chemistry data showed that specific conductance, chloride, sulfate, and pesticides increased as urbanization increased. Nutrient concentrations were not directly correlated to increases in development, but were inversely correlated to percent forest in the watershed. Analyses of SPMD-derived data showed that bioassays and certain chemical constituents such as pyrene and benzophenanthrene, both PAHs found in coal tar, were strongly correlated with measures of watershed urbanization. Hydrologic variability metrics indicated that as urban development increased, streams became flashier, with characteristic high flows having shorter duration. The hydrologic effects associated with urbanization were greatest during the fall and least apparent during the winter. No correlations were observed between increasing urbanization and stream temperature or changes in stream habitat. Algal, invertebrate, and fish communities exhibited statistically significant changes as watersheds became increasingly urban, with the strongest responses observed in the invertebrate community followed by fishes, then algal diatom communities. Invertebrate communities were the most responsive to increasing urbanization with Ephemeroptera, Plecoptera, and Tricoptera taxa, especially Plecoptera (stoneflies) responding negatively and most strongly to increasing urbanization. Invertebrate communities were influenced more significantly by water quality, although significant responses to altered hydrology also were noted. In terms of the fish community, the percentage of cyprinids present in the stream was the only Index of Biotic Integrity metric that responded negatively to increases in watershed urbanization. Fish community response to urbanization was intermediate relative to algae and invertebrates with respect to significant metric responses as well as the overall community response to increasing urbanization. Measures of hydrologic variability were the most influential environmental variables affecting the algal community. Although sites were originally chosen to represent a gradient of increasing urbanization, a cluster analysis performed on the component metrics of the urban index categorized sites into four distinct groups. Multivariate analysis based on nonmetric MDS and related analyses of data ma

Alabama, Georgia↗
USGS2005

Physical, chemical, and biological characteristics of Sturgeon Lake, Goodhue County, Minnesota, 2003-04

The U.S. Geological Survey, in cooperation with the Prairie Island Indian Community and the Minnesota Department of Natural Resources, conducted a study of Sturgeon Lake (a backwater lake in Navigation Pool 3 of the Mississippi River) during 2003-04 to describe the physical, chemical, and biological characteristics of the lake. Riparian and shoreline areas surrounding Sturgeon Lake consist primarily of deciduous tree and shrub cover with minimal amounts of commercial or residential land use. Woody debris and aquatic vegetation are the major types of physical habitat suitable for fish and invertebrates. Among 10 bottom-sediment sampling sites, 24 organic wastewater compounds, 1 organochlorine pesticide metabolite (p,p’DDE), and total polychlorinated biphenyls (PCBs) were detected in the bottom sediments of Sturgeon Lake. The most prevalent class of compounds detected were polyaromatic hydrocarbons. Other classes of compounds detected include sterols, disinfectants, plastic components, alkylphenols, and fragrances. Three compounds detected (bisphenol A, benzo[a]pyrene, and triclosan) are considered endocrine disrupting compounds. Twenty-one and 49 invertebrate taxa were identified from 10 bottom-sediment and 6 woody-debris/vegetation samples, respectively. Most of the taxa were Diptera in the family Chironomidae. The most common invertebrate in terms of density in bottom-sediment samples was the burrowing mayfly ( Hexagenia sp.). Trichoptera in the families Hydropsychidae or Polycentropodidae were common in most of the woody-debris samples. The presence of the Hexagenia larvae in samples indicates that the bottom sediments are stable and that dissolved oxygen concentrations in the lake do not drop to acute or sub-lethal anoxic conditions. Backwater lakes such as Sturgeon Lake are important areas of habitat for aquatic organisms along the Mississippi River, and this report provides baseline physical, chemical, and biological information that resource managers can compare with future investigations.

Minnesota↗
USGS1994

Physical, chemical, and biological characteristics of Pueblo Reservoir, Colorado, 1985-89

Physical, chemical, and biological characteristics of Pueblo Reservoir are described on the basis of data collected from spring 1985 through fall 1989. Also included are discussions of water quality of the upper Arkansas River Basin and the reservoir as they relate to reservoir operations. Pueblo Reservoir is a multipurpose, main-stem reservoir on the Arkansas River about 6 miles west of Pueblo, Colorado. At the top of its conservation pool, the reservoir is more than 9 miles long and ranges in depth from a few feet at the inflow to about 155 feet at the dam. Pueblo Reservoir derives most of its contents from the Arkansas River, which comprises native and transmountain flow. With respect to water temperature, the reservoir typically was well mixed to weakly stratified during the early spring and gradually became strongly stratified by May. The strong thermal stratification and underflow of the Arkansas River generally persisted into August, at which time the reservoir surface began to cool and the reservoir subsequently underwent fall turnover. Following fall turnover, the reservoir was stratified to some degree in the shallow upstream part and well mixed in the deeper middle and downstream parts. Reservoir residence times were affected by the extent of stratification present. When the reservoir was well mixed, residence times were as long as several months. During the summer when the reservoir was strongly stratified, reservoir releases were large, and when underflow was the prevalent flow pattern of the Arkansas River, reservoir residence times were as short as 30 days. Most particulate matter settled from the water column between the inflow and a distance of about 5 miles downstream. On occasions of large streamflows and sediment loads from the Arkansas River, particulate matter was transported completely through the reservoir. Water transparency, as measured with a Secchi disk, increased in a downstream direction from the reservoir inflow. The increase probably was a result of sediment settling from the water column in the upstream part of the reservoir. Secchi-disk depths in December through April were larger than those in May through November. Secchi-disk depths were small between May through August as inflow sediment loads and reservoir biomass increased. In the fall, Secchi-disk depths remained small possibly as the result of resuspension of sediment and detritus within the water column. Dissolved-oxygen concentrations generally were near supersaturation near the reservoir surface. Dissolved-oxygen concentrations decreased with increasing depth. On several occasions during the summer, dissolved oxygen became completely depleted in the hypolimnion of the downstream part of the reservoir. The most extensive period of anoxia that was measured was in August 1988; the bottom 12 to 30 feet of the downstream end of the reservoir was anoxic. Fall turnover typically resulted in well-oxygenated conditions throughout the water column from September or October through the spring. Values of pH ranged from 7.5 to 9.0 and typically were largest near the surface and decreased with depth. Dissolved-solids concentrations in the reservoir primarily are affected by dissolved solids in the inflow from the Arkansas River. Concentrations are largest during periods of decreased streamflows, September through April, and decrease with increasing streamflows in May through August. The median dissolved-solids concentration increased from 224 milligrams per liter at the inflow to 262 milligrams per liter at the outflow. However, a statistical analysis of dissolved solids indicated the apparent increase in dissolved-solids concentrations between the inflow and outflow was not significant. Calcium, sulfate, and bicarbonate are the major dissolved ions in Pueblo Reservoir. Concentrations of the major nutrients, nitrogen and phosphorus, varied within the reservoir because of settling of particulate matter, uptake by phytoplankton near the reservoir surface, and releases from the reservoir bottom sediments. Phosphorus was indicated to be a potentially growth-limiting nutrient in the reservoir because of its relatively small concentrations. During 1986 and 1987, the reservoir retained about 35 percent (359 tons) of the total nitrogen load and about 83 percent (203 tons) of the total phosphorus load. Settling of particulate matter from the water column and uptake by phytoplankton are the major nutrient sinks in the reservoir. Barium, iron, manganese, and zinc were the major trace elements in Pueblo Reservoir. Traceelement concentrations in the reservoir varied because of seasonality of trace-element concentrations in the Arkansas River, settling of particulate matter, and flux of trace elements from the bottom sediments. The aquatic-life standard in Pueblo Reservoir for total-recoverable iron (1,000 micrograms per liter) and the public water-supply standard for dissolved manganese (50 micrograms per liter) were exceeded on several occasions during the summer. Elevated concentrations of totalrecoverable iron and dissolved manganese in the Arkansas River during summer runoff contributed to exceedances in the upper part of the reservoir. Flux of manganese from the reservoir bottom sediments during periods of low or depleted dissolved-oxygen concentrations contributed to exceedances in the deeper, downstream parts of the reservoir. Concentrations of lead, mercury, and zinc were elevated in the reservoir bottom sediments and may be the result of metal-mine drainage in the upper Arkansas River Basin. Median concentrations of total organic carbon ranged from 3.1 to 4.5 milligrams per liter in May through September and from 2.5 to 3.5 milligrams per liter in October through April. Totalorganic-carbon concentrations in the reservoir were largest in the summer when streamflows and total-organic-carbon concentrations are largest in the Arkansas River. Total-organic-carbon concentrations in the reservoir decrease downstream from the reservoir inflow because of settling of particulate organic carbon. Levels of gross-alpha and gross-beta radioactivity generally were relatively low. In 7 of 31 samples collected, dissolved gross-alpha radioactivity, as natural uranium, exceeded 5 picocuries per liter, the level at which additional radiochemical analyses are recommended for drinking-water supplies. Potential sources of uranium in Pueblo Reservoir include weathering of exposed uranium ore deposits in the upper Arkansas River Basin and a uranium milling operation near Canon City. Phytoplankton densities and biovolumes measured during the winter, spring, and fall generally were indicative of a small to moderate algal biomass. Phytoplankton production tended to be largest during the summer. During the summer, phytoplankton densities and biovolumes generally were indicative of a moderate to large algal biomass. However, excessive algal production and biomass periodically occurred during the spring, summer, and fall. Three species of phytoplankton that are specifically associated with taste-and-odor problems in drinking water were identified on several occasions in water samples collected from Pueblo Reservoir. Reservoir operations and hydrodynamics can substantially affect processes that affect reservoir water quality. Stratification, underflow, and hypolimnetic withdrawals affect concentrations of dissolved solids, availability of nutrients, and concentrations of metals in the reservoir. Stratification impedes the mixing of epilimnetic and hypolimnetic waters, and the prevalent underflow that occurs during the summer results in a decrease in the potential dilution of inflowing river water with reservoir water. The underflow also decreases the maximum available nutrient load to the euphotic zone, which can, in turn, offset the maximum algal growth potential. Increased dissolved-solids, nutrient, and metal concentrations that occur in the hypolimnion during the summer are partially offset by hypolimnetic withdrawals.

Colorado↗
USGS1994

Physical, chemical, and biological data for detailed study of irrigation drainage in the Klamath Basin, California and Oregon, 1990-92

Physical, chemical, and biological data were collected between 1990 and 1992 as part of a detailed study by the U.S. Department of Interior of the effects of irrigation drainage on aquatic resources in the Klamath Basin of California and Oregon. Most of the sites for data collection were in and around the upper and lower sump of Tule Lake, in the Tule Lake National Wildlife Refuge, and along major drains in Lower Klamath National Wildlife Refuge. The physical and chemical data consist of particle-size determinations and concentrations of carbon, mercury, arsenic, chlorophenoxy acid, and organochlorine, organophosphate, and carbamate pesticides in bottom sediment; and concentrations of organophosphate, carbamate, and pyrethroid pesticides, major and trace inorganic constituents, nitrogen, phosphorus, and organic carbon in water. Continuous dissolved oxygen, pH, specific conduc- tance, and temperature data from selected sites in 1991 and 1992 are presented in graphical form to summarize the diel water-quality conditions. The biological data consists of concentrations of inorganic constituents and organochlorine pesticides in tissue, invertebrate and fish population surveys, fish health surveys, frog call surveys, egg shell thickness of avian eggs, and in situ and static toxicity bioassay data collected in 1991 and 1992 using aquatic bacteria, plants, invertebrates, fish, and bird species as test organisms.

Open-File Report↗
USGS1999

Physical, chemical, and biological data for selected streams in Chester County, Pennsylvania, 1981-94

Physical, chemical, and biological data were collected at 51 sampling sites in Chester County, Pa., from 1970 through 1994 as part of the Stream Conditions of Chester County Program. This report presents data collected from 1981 through 1994. Physical data include water temperature, instantaneous stream discharge, pH, alkalinity, specific conductance, and dissolved oxygen. Chemical data include laboratory determinations of nutrients, major ions, and selected metals in whole water samples and selected metals, pesticides, gross polychlorinated biphenyls (PCB's), gross polychlorinated napthalenes (PCN's), and total carbon in stream-bottom sediment samples. The biological data consists of benthic macroinvertebrate population analyses and diversity indices. Chester County is undergoing rapid urbanization as agricultural lands are converted to residential, commercial, and industrial areas. The purpose of the Stream Conditions of Chester County Program is to further the understanding of stream habitat and chemical changes in response to this urbanization.

Pennsylvania↗
USGS2000

Physical, chemical, and biological data for selected streams in Chester County, Pennsylvania, 1995-97

Physical, chemical, and biological data were collected at 51 sampling sites in Chester County, Pa., from 1970 through 1997 as part of the Stream Conditions of Chester County Program. This report presents data collected from 43 sites from 1995 through 1997 that constitute a continuation of the program. Physical data include water temperature, instantaneous stream discharge, pH, alkalinity, specific conductance, and dissolved oxygen. Chemical data collected include laboratory determinations of nutrients and major ions in whole water samples and selected metals, pesticides, gross polychlorinated biphenyls (PCB's), gross polychlorinated napthalenes (PCN's), and total carbon in stream-sediment samples. The biological data include benthic-macroinvertebrate populations. The data are presented without interpretation. Chester County is undergoing urbanization as agricultural land is converted to residential developments, commercial areas, and industrial and corporate parks. The major goal of the Stream Conditions of Chester County Program is to further the understanding of stream changes in response to urbanization.

Open-File Report↗
USGS1989

Physical, chemical, and biological data for selected streams in Chester County, Pennsylvania, 1969-80

This report presents physical, chemical, and biological data collected at 50 sampling sites on selected streams in Chester County, Pennsylvania from 1969 to 1980. The physical data consist of air and water temperature, stream discharge, suspended sediment, pH, specific conductance, and dissolved oxygen. The chemical data consist of laboratory determinations of total nutrients, major ions, and trace metals. The biological data consist of total coliform, fecal coliform, and fecal streptococcus bacteriological analyses, and benthicmacroinvertebrate population analyses. Brillouin's diversity index, maximum diversity, minimum diversity, and evenness for each sample, and median and mean Brilloiuin's diversity index, standard deviation, and standard error of the mean were calculated for the benthic-macroinvertebrate data for each site.

Pennsylvania↗
USGS1979

Physical, chemical, and biological characteristics of Ross Lake, Snohomish County, Washington

A study of the physical, chemical, and biological characteristics of Ross Lake in 1975 showed that the lake has no well-defined surface-water inflow and that thermal stratification is well established in summer. The water is of a calcium bicarbonate type, which is typical of lakes in western Washington. Biological productivity in the lake was low, as indicated by low to moderate chlorophyll a concentrations, by the general lack of submersed plants on the lake bottom, and by the moderate dissolved-oxygen depletion in the deeper zones during thermal stratification. The productivity probably was limited by the amount of phosphorus available. Increased productivity and the resulting growth of nuisance plants can be avoided by limiting phosphate inputs to the lake to their present or lesser rates.

Washington↗
USGS2001

Physical, Chemical, and Biological Methods and Data from the Urban Land-Use-Gradient Study, Des Plaines and Fox River Basins, Illinois, 1999-2001

Physical, chemical, and biological data were collected at 46 sites in the Fox and Des Plaines River Basins as part of the upper Illinois River Basin study of the U.S. Geological Survey?s National Water-Quality Assessment Program. The data, collected from 1999 to 2001, will be used to determine the effects of urbanization on streams in the Chicago, Illinois, metropolitan area. To examine the possible effects of urbanization on stream-water quality, the sampling sites were selected to represent a gradient of land use changing from agriculture into urban. Urban land use for the selected sites ranged from less than 1 percent urban to 92 percent urban. Data-collection methods are presented in the text portion of this report. Physical characteristics of the stream that were collected include descriptive and qualitative habitat and geomorphic measures. Water samples were analyzed for nutrients (nitrogen and phosphorus), 11 major ions, 46 wastewater indicators, pH, and specific conductance. Aquatic communities were sampled to identify and quantify populations of selected algae, benthic macroinvertebrates, and fish. There were 72 unique fish species collected at all of the sites. The number of benthic macroinvertebrate taxa collected at all the sites ranged from 15 to 48. The data and the associated data documentation are presented on a CD-ROM included with this report.

Open-File Report↗
USGS2012

Step-changes in the physical, chemical and biological characteristics of the Gulf of Maine, as documented by the GNATS time series

We identify step-changes in the physical, chemical and biological characteristics of the Gulf of Maine (GoM) using the Gulf of Maine North Atlantic Time Series (GNATS), a series of oceanographic measurements obtained between September 1998 and December 2010 along a transect in the GoM running from Portland, ME, to Yarmouth, NS. GNATS sampled a period of extremes in precipitation and river discharge (4 of the 8 wettest years of the last century occurred between 2005 and 2010). Coincident with increased precipitation, we observed the following shifts: (1) decreased salinity and density within the surface waters of the western GoM; (2) both reduced temperature and vertical temperature gradients in the upper 50 m; (3) increased colored dissolved organic matter (CDOM) concentrations and particle scattering in the western GoM; (4) increased concentrations of nitrate and phosphate across all but the eastern GoM; (5) increased silicate, particularly in the western GoM, with a sharp increase in the ratio of silicate to dissolved inorganic nitrogen; (6) sharply decreased carbon fixation by phytoplankton; (7) moderately decreased chlorophyll, particulate organic carbon (POC) and particulate inorganic carbon (PIC) in the central GoM and (8) decreased POC- and PIC-specific growth rates. Gulf-wide anomaly analyses suggest that (1) the surface density changes were predominantly driven by temperature, (2) dissolved nutrients, as well as POC/PON, varied in Redfield ratios and (3) anomalies for salinity, density, CDOM, particle backscattering and silicate were significantly correlated with river discharge. Precipitation and river discharge appear to be playing a critical role in controlling the long-term productivity of the Gulf of Maine by supplying CDOM and detrital material, which ultimately competes with phytoplankton for light absorption.

Maine↗
USGS1987

The chemical, physical and structural properties of estuarine ice in Great Bay, New Hampshire

The purpose of this study was to provide general information on the chemical, physical and structural properties of estuarine ice and show how it compares with sea ice found at higher latitudes in order to determine whether the ice in Great Bay can be used as an analog in the study of arctic sea ice. Ice cores and water samples were collected during the 1983–1984 winter season at Adams Point in Great Bay, New Hampshire. Concentrations of chloride, nitrogen (as nitrate and nitrite), bromide, phosphate, sulfate and silicate were determined for samples chosen on the basis of identifiable stratigraphic layers (i.e. bubble size and shape, sediment layers, etc.). Similarities between ice formation in Great Bay and those in the arctic regions include the nature of the freezing process and the ice types produced. In addition, the distribution and concentration of chemical constituents were found to be similar to those observed in arctic sea ice. Factors affecting the chemistry of the ice in Great Bay include rainfall during the freezing season, the presence of sediment layers in the ice cores, the nature of incorporation of brine into the crystal structure of the ice and the drainage of brine.

New Hampshire↗
USGS2009

Selected Physical, Chemical, and Biological Data Used to Study Urbanizing Streams in Nine Metropolitan Areas of the United States, 1999-2004

This report documents and summarizes physical, chemical, and biological data collected during 1999-2004 in a study titled Effects of Urbanization on Stream Ecosystems, undertaken as part of the U.S. Geological Survey's National Water-Quality Assessment Program. Data-collection methods and data processing are described in this report for streamflow; stream temperature; instream chemistry; instream aquatic habitat; and algal, macroinvertebrate, and fish communities. Data summaries prepared for analytical use are presented in downloadable data tables.

Data Series↗
USGS2009

Physical, Chemical, Ecological, and Age Data and Trench Logs from Surficial Deposits at Hatch Point, Southeastern Utah

This report presents data and describes the methodology for physical, chemical and ecological measurements of sediment, soil, and vegetation, as well as age determinations of surficial deposits at Hatch Point, Canyon Rims area, Colorado Plateau, southeastern Utah. The results presented in this report support a study that examines geomorphic and soil factors that may influence boundaries between shrubland and grassland ecosystems in the study area. Shrubland ecosystems dominated by sagebrush (Artemisia tridentata) and grassland ecosystems dominated by native perennial grasses (for example, Hilaria jamesii and Sporabolis sp.) are high-priority conservation targets for the Federal Bureau of Land Management (BLM) and other resource managers because of their diversity, productivity, and vital importance as wildlife habitat. These ecosystems have been recognized as imperiled on a regional scale since at least the mid-1990s due to habitat loss (type conversions), land-use practices, and invasive exotic plants. In the Intermountain West, the exotic annual cheatgrass (Bromus tectorum) is recognized as one of the most pervasive and serious threats to the health of native sagebrush and grassland ecosystems through effects on fire regimes and resource conditions experienced by native species.

Open-File Report↗