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USGS2019

Spatial integration of biological and social objectives to identify priority landscapes for waterfowl habitat conservation

Waterfowl population management and habitat conservation compose one of the oldest and most successful adaptive management frameworks in the world. Since its inception, the North American Waterfowl Management Plan (NAWMP) has emphasized strategically targeted conservation investments in regions that most affect waterfowl population dynamics. By 2012, regional conservation had progressively become more science-based and strategic: many migratory bird partnerships had initiated or completed projects on mapping and modeling waterfowl distribution and abundances using geospatial techniques. However, when developing a map depicting and titled “Areas of Greatest Continental Significance to North American Ducks, Geese, and Swans” for the 2012 NAWMP Revision, waterfowl professionals articulated the need for improved decision frameworks and use of consistent datasets for refining large-scale spatial products depicting priority areas for waterfowl and people. This report describes a framework for developing a spatial value model to support the identification of North American geographies of importance to waterfowl during the breeding and non-breeding periods and to resource users who could potentially support (financially and (or) politically) waterfowl habitat conservation. Objectives used to identify priority geographies were determined through a collaborative process of the NAWMP Science Support Team, Priority Landscapes Committee (PLC), and other experts in the fields of waterfowl biology and ecology, environmental science, and human dimensions. ArcGIS Desktop was used as the platform for managing, analyzing, combining and displaying the spatial data as well as producing new data through spatial analysis functions. Thirty-eight spatial layers were developed, and several composite spatially explicit products (maps of North America) were produced based on PLC recommendations. The composite products have extensive similarities to the 2012 NAWMP map depicting areas of greatest continental significance to North American waterfowl. There are also some differences, especially in regions of the high Arctic and in Mexico. These differences between spatial value model maps and the 2012 NAWMP output likely arose from inclusion of social objectives, reduced dependence on expert opinion to generate abundance estimates, lack of population surveys in some regions and availability of expanded survey data in other regions, and use of model-based waterfowl population estimates for some unsurveyed areas. The structured decision-making framework application in this study is discussed, and the appropriate use of the products and their limitations are outlined. Additionally, options for future improvements are presented by identifying gaps in data collection, waterfowl-habitat association assumptions, and uncertainties related to social objectives. These spatial products are intended for use by national, regional, and province/state level wildlife professionals to aid their decisions in targeting waterfowl habitat conservation.

Open-File Report↗
USGS2020

Biological assessment of a proposed vegetation management program to benefit tribes in eastern Oklahoma

Tribal communities may benefit from land management activities that enhance their use of resources on tribal lands. The Bureau of Indian Affairs is implementing a 5-year vegetation management program to provide support for projects that develop and use natural and cultural resources and improve opportunities for agricultural activities to benefit 20 Indian Tribes and Nations in the Eastern Oklahoma Region of the Bureau of Indian Affairs. The bureau is working with individual Tribes to identify project objectives and design treatments, which include prescribed burning, timber removal, thinning, and reduction of hazardous fuels. The total action area for the vegetation management program is estimated to be 236,575 acres, representing approximately 1 percent of the region. A biological assessment was prepared, in cooperation with the bureau and U.S. Fish and Wildlife Service, to evaluate the potential effects of the proposed vegetation management program on 22 federally threatened, endangered, and candidate species that may occur within the Eastern Oklahoma Region. The species evaluated included one plant, two insects, one reptile, five fresh-water mussels, four fishes, five birds, and four bats. Because the proposed treatments will be largely restricted to terrestrial systems, it is expected that there will be no adverse effects on the 15 species associated with aquatic habitats, provided that best management practices are followed. The proposed treatments may affect but are unlikely to adversely affect six of the primarily terrestrial species (the Papaipema eryngii [rattlesnake master borer], Picoides borealis [red-cockaded woodpecker], Myotis grisescens [gray bat], Myotis sodalis [Indiana bat], Myotis septentrionalis [northern long-eared bat], and Corynorhinus townsendii ingens [Ozark big-eared bat]), provided that best management practices are followed, including avoidance of critical habitat features. The only species likely to be adversely affected by the proposed treatments is Nicrophorus americanus (American burying beetle) as a consequence of short-term disturbances to soils and vegetation. Most adverse effects of the treatments (such as soil compaction and decreased cover in the forest understory) are expected to be short term (habitat will recover or be restored within 5 years of treatments). Less than 1 percent of the action area is expected to result in long-term adverse effects to the American burying beetle as a result of permanent cover changes that persist for more than 5 years. It is expected that the primary treatments will be largely beneficial to the American burying beetle population in the region by reducing the risk of high-severity fires and expansion of invasive woody shrubs, such as Juniperus virginiana (eastern redcedar) within potential beetle habitat and the surrounding landscape. Overall, the proposed management program is expected to provide long-term benefits to American burying beetle habitat across 91 percent of the action area.

Oklahoma↗
USGS1980

Biological premonitors of earthquakes: A validation study

For the greatest ultimate usefulness to society, the two most important facets of earthquake prediction are (1) a fundamental scientific understanding of the earthquake-triggering process and (2) the identification of reliable and measurable premonitors. A possible approach to both of these problem areas, and one that has received almost no systematic attention in U.S. seismological studies, is to examine the supposed sensitivity of biological organisms to one or more of the geophysical changes that precede earthquakes.

Open-File Report↗
USGS1985

Chemical and biological quality of selected lakes in Ohio, 1978 and 1979

Twenty-eight Ohio lakes were sampled by the U.S. Geological Survey and the Ohio Environmental Protection Agency for water-quality characteristics during the spring and summer of 1978 and 1979. This report is the third in a series covering a lake-sampling program that began in 1975. Data include water-column profiles of temperature, dissolved oxygen, pH, and specific conductance. Chemical, physical, and biological properties were measured at specific points in the water column, and selected physical and chemical properties also were measured in the principal inflows. The lakes were predominatly hard (120 180 milligrams per liter) to very hard water, although several soft-water lakes were found in southeastern Ohio. Calcium, bicarbonate, and sulfate were the principal dissolved constituents. Specific conductance ranged from 103 micromhos per centimeter (at 25 degrees Celsius) at Tycoon Lake, 1978, to 2,550 micromhos per centimeter at West Fork Mill Creek Lake, 1978. Thirteen lakes had trace-element concentrations that were above the limits for exceptional warm-water habitat recammended by the Ohio Environmental Protection Agency. Seasonal thermal gradients developed in most lakes deeper than 17 feet. Oxygen concentrations were zero or near zero during the summer sampling of the bottom water of all lakes having definite thermal gradients. Most anaerobic zones contained hydrogen sulfide and high concentrations of ammonia. All lakes were evaluated and classified by Carlson's trophic state index. Most of the lakes were classified as eutrophic. Blue-green algae (CyanophytaJ) dominated the summer algal communities. Fecal colifrom counts were within Ohio standards, although high (more than 1,000 colonies per 100 milliliters) fecal colifrom and fecal streptococcus counts were observed in West Fork Mill Creek Lake after significant runoff.

Open-File Report↗
USGS1988

Maps showing the Seabeam bathymetry and sedimentologic and biologic sample locations on Horizon Guyot, Mid-Pacific Mountains and a summary of existing data

Horizon Guyot (Fig. 1) is a 300-km-long, 75-km-wide volcanic ridge with a relatively flat summit that is diagnostic of guyots (Hess, 1946). The U. S. Geological Survey (USGS) began a study of Horizon Guyot in 1983 as part of a program on the origin, distribution, and composition of ferromanganese-oxide precipitates that encrust the hard substrate of sea floor edifices, such as seamounts and volcanic ridges (Hein and others, 1985a). Mass movement and bedload transport of sediment appears to influence the thickness of these crusts on seamount flanks (Hein and others, 1985b). Because Horizon Guyot has been studied more extensively than any other volcanic edifice in the Mid-Pacific Mountains (Heezen, Fischer, and others, 1971; Lonsdale and others, 1972; Winterer, Ewing, and others, 1973), it was chosen as the principal site for a USGS study of sediment transport processes and the geotechnical behavior of sediment on seamounts (Cacchione and others, 1988; Schwab and others, 1988). In March, 1987, Horizon Guyot was again investigated using the R/V ATLANTIS II and the D.S.R.V. ALVIN (cruise 118-12); sponsored by the National Science Foundation. Although primarily a biologic investigation, observations from 10 submersible dives, bottom samples collected at depth using ALVIN and from the surface using the ATLANTIS II, and Seabeam swath-bathymetry (sponsored by the USGS and the Office of Naval Research) add to the overall Horizon Guyot data set. In this report, we summarize the existing data base, present a Seabeam bathymetric map of the study area, ALVIN dive tracklines, the sample locations, and a brief description of the samples collected or other station activities on the ATLANTIS II cruise 118-12. The detailed bathymetric map of the study area (Plate 1) was constructed by merging data obtained by a Deep-Tow study (Lonsdale and others, 1972) (Fig. 1) with data obtained from the swath-bathymetry mapping system onboard the ATLANTIS II. Detailed information on the Seabeam bathymetric system is given by Renard and Allenou (1979).

Open-File Report↗
USGS1992

Hydrogeologic, water-quality, streamflow, bottom-sediment analyses, and biological data near the Wayne County landfill, Wayne County, Tennessee

This report summarizes the data collected as part of a hydrogeologic investigation to determine the effects of the Wayne County landfill on local water quality. The investigation was conducted from 1988 through 1989 by the U.S. Geological Survey in cooperation with the Tennessee Department of Health and Environment, Division of Superfund. The landfill was closed in November 1984 after allegations that contaminants from the landfill were affecting the quality of water from domestic wells in the Banjo Branch-Hardin Hollow valley. Test well construction data; water-quality data for selected wells, seeps, and surface-water sites: streamflow data from Banjo Branch; analyses of bottom-sediment samples: and biological data for the study area are documented in this report.

Tennessee↗
USGS1995

Biological and associated water-quality data for lower Olmos Creek and upper San Antonio River, San Antonio, Texas, March-October 1990

Biological and associated water-quality data were collected from lower Olmos Creek and upper San Antonio River in San Antonio, Texas, during March-October 1990, the second year of a multiyear data-collection program. The data will be used to document water-quality conditions prior to implementation of a proposal to reuse treated wastewater to irrigate city properties in Olmos Basin and Brackenridge Parks and to augment flows in the Olmos Creek/San Antonio River system. Benthic macroinvertebrate, periphyton, and phy toplankton communities were sampled at three sites along a 4.2-kilometer reach of the Olmos Creek/San Antonio River system. Total mean densities of benthic macroinvertebrates for the three sites ranged from 1,000 to 15,000 organisms per square meter. The most abundant macroinvertebrates were the class Insecta (insects). Total densities of periphyton ranged from 700 to 86,000 cells per square millimeter. Cyanophyta (blue-green algae) and Bacillariophyta (diatoms) were the predominant periphyton organisms. Total densities of phytoplankton ranged from 940 to 21,000 cells per milliliter. Diatoms and Chlorophyta (green algae) made up most of the rest of the phytoplankton. Mean diversity index for the three sites ranged from 1.0 to 2.1 for benthic macroinvertebrates. The diversity index for all sites ranged from 1.5 to 3.1 for periphyton and 0.9 to 2.5 for phytoplankton. Hardness ranged from 220 to 280 milligrams per liter as calcium carbonate, and alkalinity ranged from 173 to 213 milligrams per liter as calcium carbonate. The largest dissolved nitrate concentration was 1.68 milligrams per liter. Dissolved ammonia nitrogen generally was less than 0.100 milligram per liter. The largest total phosphorus concentration was 0.080 milligram per liter, over one-half of which was dissolved orthophosphate. Total aluminum and total iron were the only trace elements in water to exceed the reporting threshold by large concentrations. Total aluminum concentrations ranged from 100 to 250 micrograms per liter, and total iron concentrations ranged from 70 to 280 micrograms per liter. Lead was the most prominent trace element in bottommaterial samples with concentrations ranging from 40 to 190 micrograms per gram. The maximum copper concentration in the bottom material was 60 micrograms per gram at site 3 (the most downstream site). Depths and velocities, measured at sample points after benthic macroinvertebrate sampling, ranged from 0.03 to 0.30 meter and from 0.06 to 1.2 meters per second, respectively. Measurable stream discharge ranged from 0.01 to 0.27 cubic meter per second. During two of the sampling periods, no flow was at site 1.

Open-File Report↗
USGS1995

Biological and associated water-quality data for lower Olmos Creek and upper San Antonio River, San Antonio, Texas, April - September 1989

Biological and associated water-quality data were collected from lower Olmos Creek and upper San Antonio River in San Antonio, Texas, during April-September 1989. Benthic macroinvertebrate, periphyton, and phytoplankton communities were sampled at three sites along the Olmos Creek/San Antonio River system. Total mean densities of benthic macroinvertebrates for the three sites ranged from 670 to 10,000 organisms per square meter. The most abundant macroinvertebrates were the class Insecta (insects). Total densities of periphyton ranged from 2,900 to 110,000 cells per square millimeter. Cyanophyta (blue-green algae) and Bacillariophyta (diatoms) were the predominant periphyton organisms. Total densities of phyto- plankton ranged from 5,000 to 47,000 cells per square milliliter. Blue-green algae accounted for more than one- half of the phytoplankton in each sample. Hardness ranged from 160 to 250 milligrams per liter as calcium carbonate, and alkalinity ranged from 130 to 220 milligrams per liter as calcium carbonate. The largest dissolved nitrite concentration was 0.038 milligram per liter. The largest total phosphorus concentration was 0.150 milligram per liter, over one-half of which was dissolved orthophosphate. Total aluminum and total iron were the only trace elements in water to exceed the reporting threshold by large concen- trations. Total aluminum concentrations ranged from 70 to 280 micrograms per liter, and total iron concentrations ranged from 70 to 340 micrograms per liter. Lead was the most prominent trace element in bottom-material samples, with concentrations ranging from 30 to 230 micrograms per gram.

Open-File Report↗
USGS1995

Water-quality, discharge, and biologic data for streams and springs in the Highland Rim Escarpment of southeastern Bedford County, Tennessee

From November 1994 through April 1995, streams and springs in 9 drainage basins were observed and sampled at 176 sites to obtain information on environmental quality near the Quail Hollow landfill, Bedford County, Tennessee. Reconnaissance data were collected to establish a regional pattern. Water samples from 26 seepage sites were analyzed to determine water-quality conditions. During the reconnaissance, conductivity ranged regionally from 17 to 617 microsiemens per centimeter. The greatest biologic diversity was in Bennett Branch, followed by Daniel Hollow, Prince, Powell and Renegar, County Line, and Anthony Branches, Hurricane Creek, and Anderton Branch, respectively. In general, conductivity was less than 50 microsiemens per centimeter at and upstream of the Chattanooga Shale but increased downstream to between 200 and 300 microsiemens per centimeter. Of the constituents and properties analyzed, only pH and four metals at six sites had values that were not within the limits set by the State of Tennessee for drinking water. Chloride and dissolved manganese concentrations were highest for a spring and a seep adjacent to the landfill. Scans indicated the presence of about 37 unidentified organic compounds at these same two sites.

Tennessee↗
USGS1999

Physical, chemical, and biological data for two sites on the upper Kenai River, Alaska, 1998

Water-quality data were collected and stream characteristics were documented from two sites along the upper Kenai River in the Kenai National Wildlife Refuge, Alaska. These data were collected to describe the current status of the sites and to provide baseline information from which changes in the future could be evaluated. Physical characteristics included channel geometry surveys, and measurements of channel widths and water discharge at each site. Chemical data included stream water temperature, dissolved-oxygen concentration, pH, specific conductance, E. coli and fecal coliform counts, and nutrient concentration. Data on concentrations of trace elements and various organic compounds in bed sediments and the tissue of slimy sculpin were also collected. Biological characteristics were evaluated using measurements of the bacteria, benthic macroinvertebrate, and fish communities.

Open-File Report↗
USGS1976

Physical, chemical, and biological aspects of subsurface organic waste injection near Wilmington, North Carolina

From May 1968 to December 1972, an industrial organic waste was injected at rates of 100 to 200 gallons per minute (6.3 to 12.6 litres per second) into a sand, gravel, and limestone aquifer of Late Cretaceous age by Hercules Inc. located near Wilmington, North Carolina. This report presents both field and laboratory data pertaining to the physical, chemical, and biological effects of waste injection into the subsurface at this particular site, a case history of the operation, predictions of the reactions between certain organic wastes and the aquifer components, and descriptions of the effects of these reactions on the subsurface movement of the wastes. The case history documents a situation in which subsurface waste injection could not be considered a successful means of waste disposal. The first injection well was used only for 1 year due to excessive wellhead pressure build-up above the specified pressure limit of 150 pounds per square inch (10.3 bars). A second injection well drilled as a replacement operated for only 5 months before it too began to have problems with plugging. Upward leakage of waste into shallower aquifers was also detected at several wells in the injection-observation well system. The multiple problems of plugging, high pressures, and waste leakage suggested that the reactive nature of the waste with the aquifer into which it was injected was the primary reason for the difficulties experienced with waste injection. A site study was initiated in June 1971 to investigate waste-aquifer interactions. The first stage of the study determined the hydrogeologic conditions at the site, and characterized the industrial waste and the native ground water found in the injection zone and other aquifers. The injection zone consisted of multiple permeable zones ranging in depth from about 850 to 1,000 feet (259 to 305 metres) below land surface. In addition to the injection zone, aquifers were found near depths of 60, 300, 500, and 700 feet (18, 91, 152, and 213 metres) below land surface. The aquifers from 300 feet (91 metres) down to the injection zone were flowing artesian with the natural pressure of the injection zone being 65 feet (20 metres) above land surface at the site. The dissolved solids concentration in the native ground water increased with depth to an average value of 20,800 mg/l (milligram per litre) (two-thirds that of seawater) in the water from the injection zone. Sodium chloride was the major dissolved solid, and all of the ground water below 300-feet (91-metres) depth was slightly alkaline. Dissolved organic carbon of the industrial waste averaged 7,100 mg/l and 95 percent of the organic carbon was identified and quantified. The major organic waste constituents in order of decreasing abundance were acetic acid, formic acid, p-toluic acid, formaldehyde, methanol, terephthalic acid, phthalic acid, and benzoic acid. Prior to injection, the waste was neutralized with lime to pH 4 so that the major inorganic waste constituent was calcium at a concentration of 1,300 mg/l. The second stage of the site study involved the observation of waste-aquifer interactions at various wells as the waste arrived and passed by the wells. Water samples obtained from three observation wells located 1,500 to 2,000 feet (457 to 607 metres) from the original injection well gave evidence for biochemical waste transformations at low waste concentrations. Gas that effervesced from these water samples contained up to 54 percent methane by volume. Ferrous iron concentrations as high as 35 mg/l, hydrogen sulfide gas, and sulfide precipitates were additional indicators of biochemical reductive processes in the subsurface environment. Approximately 3,000 organisms per millilitre were found in uncontaminated ground water from the injection zone whereas in waste-contaminated wells, the number increased to levels as high as 1,000,000 organisms per millilitre. High concentrations of waste were found to be toxic to microo

Professional Paper↗
USGS2011

Geospatial characteristics of Florida's coastal and offshore environments: Distribution of important habitats for coastal and offshore biological resources and offshore sand resources

The Geospatial Characteristics GeoPDF of Florida's Coastal and Offshore Environments is a comprehensive collection of geospatial data describing the political boundaries and natural resources of Florida. This interactive map provides spatial information on bathymetry, sand resources, and locations of important habitats (for example, Essential Fish Habitats (EFH), nesting areas, strandings) for marine invertebrates, fish, reptiles, birds, and marine mammals. The map should be useful to coastal resource managers and others interested in marine habitats and submerged obstructions of Florida's coastal region. In particular, as oil and gas explorations continue to expand, the map can be used to explore information regarding sensitive areas and resources in the State of Florida. Users of this geospatial database will have access to synthesized information in a variety of scientific disciplines concerning Florida's coastal zone. This powerful tool provides a one-stop assembly of data that can be tailored to fit the needs of many natural resource managers. The map was originally developed to assist the Bureau of Ocean Energy Management, Regulation, and Enforcement (BOEMRE) and coastal resources managers with planning beach restoration projects. The BOEMRE uses a systematic approach in planning the development of submerged lands of the Continental Shelf seaward of Florida's territorial waters. Such development could affect the environment. BOEMRE is required to ascertain the existing physical, biological, and socioeconomic conditions of the submerged lands and estimate the impact of developing these lands. Data sources included the National Oceanic and Atmospheric Administration, BOEMRE, Florida Department of Environmental Protection, Florida Geographic Data Library, Florida Fish and Wildlife Conservation Commission, Florida Natural Areas Inventory, and the State of Florida, Bureau of Archeological Research. Federal Geographic Data Committee (FGDC) compliant metadata are provided as attached xml files for all geographic information system (GIS) layers.

Florida↗
USGS2004

Water-quality, biological, and physical-habitat conditions at fixed sites in the Cook Inlet Basin, Alaska, National Water-Quality Assessment Study Unit, October 1998-September 2001

The Cook Inlet Basin study unit of the U.S. Geological Survey National Water-Quality Assessment Program comprises 39,325 square miles in south-central Alaska. Data were collected at eight fixed sites to provide baseline information in areas where no development has taken place, urbanization or logging have occurred, or the effects of recreation are increasing. Collection of water-quality, biology, and physical-habitat data began in October 1998 and ended in September 2001 (water years 1999-2001). The climate for the water years in the study may be categorized as slightly cool-wet (1999), slightly warm-wet (2000), and significantly warm-dry (2001). Total precipitation was near normal during the study period, and air temperatures ranged from modestly cool in water year 1999 to near normal in 2000, and to notably warm in 2001. Snowmelt runoff dominates the hydrology of streams in the Cook Inlet Basin. Average annual flows at the fixed sites were approximately the same as the long-term average annual flows, with the exception of those in glacier-fed basins, which had above-average flow in water year 2001. Water temperature of all streams studied in the Cook Inlet Basin remained at 0 oC for about 6 months per year, and average annual water temperatures ranged from 3.3 to 6.2 degrees Celsius. Of the water-quality constituents sampled, all concentrations were less than drinking-water standards and only one constituent, the pesticide carbaryl, exceeded aquatic-life standards. Most of the stream waters of the Cook Inlet Basin were classified as calcium bicarbonate, which reflects the underlying geology. Streams in the Cook Inlet Basin draining areas with glaciers, rough mountainous terrain, and poorly developed soils have low concentrations of nitrogen, phosphorus, and dissolved organic carbon compared with concentrations of these same constituents in streams in lowland or urbanized areas. In streams draining relatively low-lying areas, most of the suspended sediment, nutrients, and dissolved organic carbon are transported in the spring from the melting snowpack. The urbanized stream, Chester Creek, had the highest concentrations of calcium, magnesium, chloride, and sodium, most likely because of the application of de-icing materials during the winter. Several volatile organic compounds and pesticides also were detected in samples from this stream. Aquatic communities in the Cook Inlet Basin are naturally different than similar sites in the contiguous United States because of the unique conditions of the northern latitudes where the Cook Inlet Basin is located, such as extreme diurnal cycles and long periods of ice cover. Blue-green algae was the dominant algae found at all sites although in some years green algae was the most dominant algae. Macroinvertebrate communities consist primarily of Diptera (true flies), Ephemeroptera (mayflies), and Plecoptera (stoneflies). Lowland areas have higher abundance of aquatic communities than glacier-fed basins. However, samples from the urbanized stream, Chester Creek, were dominated by oligochaetes, a class of worms. Most of the functional feeding groups were collector-gatherers. The number of taxa for both algae and macroinvertebrates were highest in water year 2001, which may be due to the relative mild winter of 2000?2001 and the above average air temperatures for this water year. The streams in the Cook Inlet Basin typically are low gradient. Bank substrates consist of silt, clay, or sand, and bed substrate consists of coarse gravel or cobbles. Vegetation is primarily shrubs and woodlands with spruce or cottonwood trees. Canopy angles vary with the size of the stream or river and are relatively low at the smaller streams and high at the larger streams. Suitable fish habitat, such as woody debris, pools, cobble substrate, and overhanging vegetation, is found at most sites. Of the human activities occurring in the fixed site basins ? high recreational use, logging, and urbanizat

Scientific Investigations Report↗
USGS2005

Hydrologic, water-quality, and biological assessment of Laguna de las Salinas, Ponce, Puerto Rico, January 2003-September 2004

The Laguna de Las Salinas is a shallow, 35-hectare, hypersaline lagoon (depth less than 1 meter) in the municipio of Ponce, located on the southern coastal plain of Puerto Rico. Hydrologic, water-quality, and biological data in the lagoon were collected between January 2003 and September 2004 to establish baseline conditions. During the study period, rainfall was about 1,130 millimeters, with much of the rain recorded during three distinct intense events. The lagoon is connected to the sea by a shallow, narrow channel. Subtle tidal changes, combined with low rainfall and high evaporation rates, kept the lagoon at salinities above that of the sea throughout most of the study. Water-quality properties measured on-site (temperature, pH, dissolved oxygen, specific conductance, and Secchi disk transparency) exhibited temporal rather than spatial variations and distribution. Although all physical parameters were in compliance with current regulatory standards for Puerto Rico, hyperthermic and hypoxic conditions were recorded during isolated occasions. Nutrient concentrations were relatively low and in compliance with current regulatory standards (less than 5.0 and 1.0 milligrams per liter for total nitrogen and total phosphorus, respectively). The average total nitrogen concentration was 1.9 milligrams per liter and the average total phosphorus concentration was 0.4 milligram per liter. Total organic carbon concentrations ranged from 12.0 to 19.0 milligrams per liter. Chlorophyll a was the predominant form of photosynthetic pigment in the water. The average chlorophyll a concentration was 13.4 micrograms per liter. Chlorophyll b was detected (detection limits 0.10 microgram per liter) only twice during the study. About 90 percent of the primary productivity in the Laguna de Las Salinas was generated by periphyton such as algal mats and macrophytes such as seagrasses. Of the average net productivity of 13.6 grams of oxygen per cubic meter per day derived from the diel study, the periphyton and macrophyes produced 12.3 grams per cubic meter per day; about 1.3 grams (about 10 percent) were produced by the phytoplankton (plant and algae component of plankton). The total respiration rate was 59.2 grams of oxygen per cubic meter per day. The respiration rate ascribed to the plankton (all organisms floating through the water column) averaged about 6.2 grams of oxygen per cubic meter per day (about 10 percent), whereas the respiration rate by all other organisms averaged 53.0 grams of oxygen per cubic meter per day (about 90 percent). Plankton gross productivity was 7.5 grams per cubic meter per day; the gross productivity of the entire community averaged 72.8 grams per cubic meter per day. Fecal coliform bacteria counts were generally less than 200 colonies per 100 milliliters; the highest concentration was 600 colonies per 100 milliliters.

Scientific Investigations Report↗
USGS2006

Water Quality, Physical Habitat, and Biology of the Kijik River Basin, Lake Clark National Park and Preserve, Alaska, 2004-2005

The U.S. Geological Survey and the National Park Service conducted a water-quality investigation of the Kijik River Basin in Lake Clark National Park and Preserve from June 2004 to March 2005. The Kijik River Basin was studied because it has a productive sockeye salmon run that is important to the larger Kvichak River watershed. Water-quality, physical habitat, and biological characteristics were assessed. Water type throughout the Kijik River Basin is calcium bicarbonate although Little Kijik River above Kijik Lake does have slightly higher concentrations of sulfate and chloride. Alkalinity concentrations are generally less than 28 milligrams per liter, indicating a low buffering capacity of these waters. Lachbuna Lake traps much of the suspended sediment from the glacier streams in the headwaters of the basin as evidenced by low secchi-disc transparency of 1 to 2 meters and low suspended sediment concentrations in the Kijik River downstream from the lake. Kijik Lake is a fed by clearwater streams and has secchi-disc readings ranging from 11 to 15 meters. Streambed sediments collected from four surface sites analyzed for trace elements indicated that arsenic concentrations at all sites were above proposed guidelines. However, arsenic concentrations are due to the local geology, not anthropogenic factors. Benthic macroinvertebrate qualitative multi-habitat samples collected from two sites on the Little Kijik River and two sites on the main stem of the Kijik River indicated a total of 69 taxa present among the four sites. The class Insecta, made up the largest percentage of macroinvertebrates, totaling 70 percent of the families found. The insects were comprised of four orders; Diptera (flies and midges), Ephemeroptera (mayflies), Plecoptera (stoneflies), and Trichoptera (caddisflies). One-hundred twenty-two species of periphytic algae were identified in qualitative multi-habitat samples collected at the four stream sites. Eight species of non-motile, diatoms were collected from all four stream sites suggesting that the areas from which they were collected are relatively stable and unaffected by sedimentation.

Scientific Investigations Report↗
USGS2007

Nutrient and biological conditions of selected small streams in the Edwards Plateau, central Texas, 2005-06, and implications for development of nutrient criteria

During the summers of 2005 and 2006 the U.S. Geological Survey, in cooperation with the Texas Commission on Environmental Quality, evaluated nutrient and biological conditions in small streams in parts of the Edwards Plateau of Central Texas. Land-cover analysis was used to select 15 small streams that represented a gradient of conditions with the potential to affect nutrient concentrations across the study area, which comprises two of four subregions of the Edwards Plateau ecoregion. All 15 streams were sampled for water properties, nutrients, algae, benthic invertebrates, and fish in summer 2005, and eight streams were resampled in summer 2006. Streams that did not receive wastewater effluent had relatively low nutrient concentrations and were classified as oligotrophic; streams receiving wastewater effluent had relatively high nutrient concentrations and were classified as eutrophic. Nutrient concentrations measured in the least-disturbed streams closely matched the U.S. Environmental Protection Agency nutrient criteria recommendations based on estimated reference concentrations. Nitrogen/phosphorus ratios indicated streams not affected by wastewater effluent might be limited by phosphorus concentrations. Algal indicators of nutrient condition were closely related to dissolved nitrogen concentrations and streamflow conditions. Ambient dissolved nitrogen concentrations (nitrite plus nitrate) were positively correlated with benthic algal chlorophyll-a concentrations. The correlation of benthic algal chlorophyll-a with instantaneous nitrite plus nitrate load was stronger than correlations with ambient nutrients. Increased nutrient concentrations were associated with increased macroalgae cover, wider diel dissolved oxygen ranges, and reduced diel dissolved oxygen minimums. Benthic invertebrate aquatic life use scores generally were classified as High to Exceptional in study streams despite the influence of urbanization or wastewater effluent. Reductions in aquatic life use scores appeared to be related to extremely low flow conditions and the loss of riffle habitats. Benthic invertebrate aquatic life use scores and several of the metrics used to compute composite aquatic life use scores tended to increase with increasing total nitrogen concentrations. Fish community aquatic life use scores generally were classified as High or Exceptional with the exception of a few samples collected from streams receiving wastewater effluent that were classified as Intermediate. Fish community aquatic life use scores and several fish community metrics were positively correlated with nutrient concentrations and macroalgae cover. The majority of the positive correlations among nutrient concentrations, macroalgae cover, and fish metrics were strongly influenced by relatively high nutrient concentrations. Both benthic and planktonic chlorophyll-a measures were related to nutrients, but this study indicates that benthic chlorophyll-a was the better choice for monitoring nutrient enrichment because (1) the relation between benthic chlorophyll-a and nutrients was stronger, and (2) a strong relation between benthic chlorophyll-a and nutrients persisted after removal of the sites influenced by wastewater effluent, which indicates superior ability of benthic chlorophyll-a to discriminate between conditions at lower nutrient concentrations. The transect-based algal abundance estimate technique is a useful tool for identifying eutrophic conditions, assessing nuisance algal growth, and making broad comparisons among sites, but it appears to lack the fine resolution to identify lesser degrees of nutrient enrichment. Several individual benthic invertebrate and fish metrics were correlated with nutrient conditions, but correlations were generally positive and the reverse of what would be expected when nutrient enrichment causes a proliferation of algal growth and stream degradation. However, the benthic invertebrate functional feeding group metrics showed some

Scientific Investigations Report↗
USGS2010

Selected Hydrologic, Water-Quality, Biological, and Sedimentation Characteristics of Laguna Grande, Fajardo, Puerto Rico, March 2007-February 2009

Laguna Grande is a 50-hectare lagoon in the municipio of Fajardo, located in the northeasternmost part of Puerto Rico. Hydrologic, water-quality, and biological data were collected in the lagoon between March 2007 and February 2009 to establish baseline conditions and determine the health of Laguna Grande on the basis of preestablished standards. In addition, a core of bottom material was obtained at one site within the lagoon to establish sediment depositional rates. Water-quality properties measured onsite (temperature, pH, dissolved oxygen, specific conductance, and water transparency) varied temporally rather than areally. All physical properties were in compliance with current regulatory standards established for Puerto Rico. Nutrient concentrations were very low and in compliance with current regulatory standards (less than 5.0 and 1.0 milligrams per liter for total nitrogen and total phosphorus, respectively). The average total nitrogen concentration was 0.28 milligram per liter, and the average total phosphorus concentration was 0.02 milligram per liter. Chlorophyll a was the predominant form of photosynthetic pigment in the water. The average chlorophyll-a concentration was 6.2 micrograms per liter. Bottom sediment accumulation rates were determined in sediment cores by modeling the downcore activities of lead-210 and cesium-137. Results indicated a sediment depositional rate of about 0.44 centimeter per year. At this rate of sediment accretion, the lagoon may become a marshland in about 700 to 900 years. About 86 percent of the community primary productivity in Laguna Grande was generated by periphyton, primarily algal mats and seagrasses, and the remaining 14 percent was generated by phytoplankton in the water column. Based on the diel studies the total average net community productivity equaled 5.7 grams of oxygen per cubic meter per day (2.1 grams of carbon per cubic meter per day). Most of this productivity was ascribed to periphyton and macrophytes, which produced 4.9 grams of oxygen per cubic meter per day (1.8 grams of carbon per cubic meter per day). Phytoplankton, the plant and algal component of plankton, produced about 0.8 gram of oxygen per cubic meter per day (0.3 gram of carbon per cubic meter per day). The total diel community respiration rate was 23.4 grams of oxygen per cubic meter per day. The respiration rate ascribed to plankton, which consists of all free floating and swimming organisms in the water column, composed 10 percent of this rate (2.9 grams of oxygen per cubic meter per day); respiration by all other organisms composed the remaining 90 percent (20.5 grams of oxygen per cubic meter per day). Plankton gross productivity was 3.7 grams of oxygen per cubic meter per day, equivalent to about 13 percent of the average gross productivity for the entire community (29.1 grams of oxygen per cubic meter per day). The average phytoplankton biomass values in Laguna Grande ranged from 6.0 to 13.6 milligrams per liter. During the study, Laguna Grande contained a phytoplankton standing crop of approximately 5.8 metric tons. Phytoplankton community had a turnover (renewal) rate of about 153 times per year, or roughly about once every 2.5 days. Fecal indicator bacteria concentrations ranged from 160 to 60,000 colonies per 100 milliliters. Concentrations generally were greatest in areas near residential and commercial establishments, and frequently exceeded current regulatory standards established for Puerto Rico.

Scientific Investigations Report↗
USGS2010

Surface-water quantity and quality, aquatic biology, stream geomorphology, and groundwater-flow simulation for National Guard Training Center at Fort Indiantown Gap, Pennsylvania, 2002-05

Base-line and long-term monitoring of water resources of the National Guard Training Center at Fort Indiantown Gap in south-central Pennsylvania began in 2002. Results of continuous monitoring of streamflow and turbidity and monthly and stormflow water-quality samples from two continuous-record long-term stream sites, periodic collection of water-quality samples from five miscellaneous stream sites, and annual collection of biological data from 2002 to 2005 at 27 sites are discussed. In addition, results from a stream-geomorphic analysis and classification and a regional groundwater-flow model are included. Streamflow at the facility was above normal for the 2003 through 2005 water years and extremely high-flow events occurred in 2003 and in 2004. Water-quality samples were analyzed for nutrients, sediments, metals, major ions, pesticides, volatile and semi-volatile organic compounds, and explosives. Results indicated no exceedances for any constituent (except iron) above the primary and secondary drinking-water standards or health-advisory levels set by the U.S. Environmental Protection Agency. Iron concentrations were naturally elevated in the groundwater within the watershed because of bedrock lithology. The majority of the constituents were at or below the method detection limit. Sediment loads were dominated by precipitation due to the remnants of Hurricane Ivan in September 2004. More than 60 percent of the sediment load measured during the entire study was transported past the streamgage in just 2 days during that event. Habitat and aquatic-invertebrate data were collected in the summers of 2002-05, and fish data were collected in 2004. Although 2002 was a drought year, 2003-05 were above-normal flow years. Results indicated a wide diversity in invertebrates, good numbers of taxa (distinct organisms), and on the basis of a combination of metrics, the majority of the 27 sites indicated no or slight impairment. Fish-metric data from 25 sites indicated results similar to the invertebrate data. Stream classification based on evolution of the stream channels indicates about 94 percent of the channels were considered to be in equilibrium (type B or C channels), neither aggrading nor eroding. A regional, uncalibrated groundwater-flow model indicated the surface-water and groundwater-flow divides coincided. Because of folding of rock layers, groundwater was under confined conditions and nearly all the water leaves the facility via the streams.

Scientific Investigations Report↗