Geology topics

Research about Missouri

Source-linked reports with geographic coverage including Missouri.

At least 199 records · Page 11Linked to original sources

USGS2014

Bathymetric surveys and area/capacity tables of water-supply reservoirs for the city of Cameron, Missouri, July 2013

Years of sediment accumulation and dry conditions in recent years have led to the decline of water levels and capacities for many water-supply reservoirs in Missouri, and have caused renewed interest in modernizing outdated area/capacity tables for these reservoirs. The U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources, surveyed the bathymetry of the four water-supply reservoirs used by the city of Cameron, Missouri, in July 2013. The data were used to provide water managers with area/capacity tables and bathymetric maps of the reservoirs at the time of the surveys.

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USGS2014

Geologic field notes and geochemical analyses of outcrop and drill core from Mesoproterozoic rocks and iron-oxide deposits and prospects of southeast Missouri

The U.S. Geological Survey, in cooperation with the Missouri Department of Natural Resources/Missouri Geological Survey, undertook a study from 1988 to 1994 on the iron-oxide deposits and their host Mesoproterozoic igneous rocks in southeastern Missouri. The project resulted in an improvement of our understanding of the geologic setting, mode of formation, and the composition of many of the known deposits and prospects and the associated rocks of the St. Francois terrane in Missouri. The goal for this earlier work was to allow the comparison of Missouri iron-oxide deposits in context with other iron oxide-copper ± uranium (IOCG) types of mineral deposits observed globally. The raw geochemical analyses were released originally through the USGS National Geochemical Database (NGDB, http://mrdata.usgs.gov). The data presented herein offers all of the field notes, locations, rock descriptions, and geochemical analyses in a coherent package to facilitate new research efforts in IOCG deposit types. The data are provided in both Microsoft Excel (Version Office 2010) spreadsheet format (*.xlsx) and MS-DOS text formats (*.txt) for ease of use by numerous computer programs.

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USGS2014

Occurrence and origin of Escherichia coli in water and sediments at two public swimming beaches at Lake of the Ozarks State Park, Camden County, Missouri, 2011-13

In the past several years, the Missouri Department of Natural Resources has closed two popular public beaches, Grand Glaize Beach and Public Beach 1, at Lake of the Ozarks State Park in Osage Beach, Missouri when monitoring results exceeded the established Escherichia coli (E. coli) standard. As a result of the beach closures, the U.S. Geological Survey and Missouri University of Science and Technology, in cooperation with the Missouri Department of Natural Resources, led an investigation into the occurrence and origins of E. coli at Grand Glaize Beach and Public Beach 1. The study included the collection of more than 1,300 water, sediment, and fecal source samples between August 2011 and February 2013 from the two beaches and vicinity. Spatial and temporal patterns of E. coli concentrations in water and sediments combined with measurements of environmental variables, beach-use patterns, and Missouri Department of Natural Resources water-tracing results were used to identify possible sources of E. coli contamination at the two beaches and to corroborate microbial source tracking (MST) sampling efforts. Results from a 2011 reconnaissance sampling indicate that water samples from Grand Glaize Beach cove contained significantly larger E. coli concentrations than adjacent coves and were largest at sites at the upper end of Grand Glaize Beach cove, indicating a probable local source of E. coli contamination within the upper end of the cove. Results from an intensive sampling effort during 2012 indicated that E. coli concentrations in water samples at Grand Glaize Beach cove were significantly larger in ankle-deep water than waist-deep water, trended downward during the recreational season, significantly increased with an increase in the total number of bathers at the beach, and were largest during the middle of the day. Concentrations of E. coli in nearshore sediment (sediment near the shoreline) at Grand Glaize Beach were significantly larger in foreshore samples (samples collected above the shoreline) than in samples collected in ankle-deep water below the shoreline, significantly larger in the left and middle areas of the beach than the right area, and substantially larger than similar studies at E. coli- contaminated beaches on Lake Erie in Ohio. Concentrations of E. coli in the water column also were significantly larger after resuspension of sediments. Results of MST indicate a predominance of waterfowl-associated markers in nearshore sediments at Grand Glaize Beach consistent with frequent observations of goose and vulture fecal matter in sediment, especially on the left and middle areas of the beach. The combination of spatial and temporal sampling and MST indicate that an important source of E. coli contamination at Grand Glaize Beach during 2012 was E. coli released into the water column by bathers resuspending E. coli-contaminated sediments, especially during high-use days early in the recreational season.

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USGS2014

Bathymetric and velocimetric surveys at highway bridges crossing the Missouri River between Kansas City and St. Louis, Missouri, April-May, 2013

Bathymetric and velocimetric data were collected by the U.S. Geological Survey, in cooperation with the Missouri Department of Transportation, in the vicinity of 10 bridges at 9 highway crossings of the Missouri River between Lexington and Washington, Missouri, from April 22 through May 2, 2013. A multibeam echosounder mapping system was used to obtain channel-bed elevations for river reaches ranging from 1,640 to 1,840 feet longitudinally and extending laterally across the active channel between banks and spur dikes in the Missouri River during low- to moderate-flow conditions. These bathymetric surveys indicate the channel conditions at the time of the surveys and provide characteristics of scour holes that may be useful in the development of predictive guidelines or equations for scour holes. These data also may be useful to the Missouri Department of Transportation to assess the bridges for stability and integrity issues with respect to bridge scour during floods. Bathymetric data were collected around every pier that was in water, except those at the edge of water or in very shallow water (less than about 6 feet). Scour holes were present at most piers for which bathymetry could be obtained, except at piers on channel banks, near or embedded in lateral or longitudinal spur dikes, and on exposed bedrock outcrops. Scour holes observed at the surveyed bridges were examined with respect to depth and shape. Although exposure of parts of foundational support elements was observed at several piers, at most sites the exposure likely can be considered minimal compared to the overall substructure that remains buried in channel-bed material; however, there were several notable exceptions where the bed material thickness between the bottom of the scour hole and bedrock was less than 6 feet. Such substantial exposure of usually buried substructural elements may warrant special observation in future flood events. Previous bathymetric surveys had been done at all of the sites in this study during the flood of 2011. Comparisons between bathymetric surfaces from the previous surveys and those of this study generally indicate a consistent increase in the elevation of the bed and decrease in the size of scour holes at these sites, both likely caused by a substantial decrease in discharge and water-surface elevation compared to the 2011 surveys at most sites. However, multiple surveys at one of the sites indicate that the flow condition is not the sole variable in the determination of the size of scour holes at sites with a dual bridge configuration. Furthermore, another site had a smaller and shallower scour hole even though the discharge in this study was slightly greater than in 2011. Pier size, nose shape, and alignment to flow also had a substantial effect on the size of the scour hole observed.

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USGS2014

Methods for estimating annual exceedance-probability discharges and largest recorded floods for unregulated streams in rural Missouri

Regression analysis techniques were used to develop a set of equations for rural ungaged stream sites for estimating discharges with 50-, 20-, 10-, 4-, 2-, 1-, 0.5-, and 0.2-percent annual exceedance probabilities, which are equivalent to annual flood-frequency recurrence intervals of 2, 5, 10, 25, 50, 100, 200, and 500 years, respectively. Basin and climatic characteristics were computed using geographic information software and digital geospatial data. A total of 35 characteristics were computed for use in preliminary statewide and regional regression analyses. Annual exceedance-probability discharge estimates were computed for 278 streamgages by using the expected moments algorithm to fit a log-Pearson Type III distribution to the logarithms of annual peak discharges for each streamgage using annual peak-discharge data from water year 1844 to 2012. Low-outlier and historic information were incorporated into the annual exceedance-probability analyses, and a generalized multiple Grubbs-Beck test was used to detect potentially influential low floods. Annual peak flows less than a minimum recordable discharge at a streamgage were incorporated into the at-site station analyses. An updated regional skew coefficient was determined for the State of Missouri using Bayesian weighted least-squares/generalized least squares regression analyses. At-site skew estimates for 108 long-term streamgages with 30 or more years of record and the 35 basin characteristics defined for this study were used to estimate the regional variability in skew. However, a constant generalized-skew value of -0.30 and a mean square error of 0.14 were determined in this study. Previous flood studies indicated that the distinct physical features of the three physiographic provinces have a pronounced effect on the magnitude of flood peaks. Trends in the magnitudes of the residuals from preliminary statewide regression analyses from previous studies confirmed that regional analyses in this study were similar and related to three primary physiographic provinces. The final regional regression analyses resulted in three sets of equations. For Regions 1 and 2, the basin characteristics of drainage area and basin shape factor were statistically significant. For Region 3, because of the small amount of data from streamgages, only drainage area was statistically significant. Average standard errors of prediction ranged from 28.7 to 38.4 percent for flood region 1, 24.1 to 43.5 percent for flood region 2, and 25.8 to 30.5 percent for region 3. The regional regression equations are only applicable to stream sites in Missouri with flows not significantly affected by regulation, channelization, backwater, diversion, or urbanization. Basins with about 5 percent or less impervious area were considered to be rural. Applicability of the equations are limited to the basin characteristic values that range from 0.11 to 8,212.38 square miles (mi 2 ) and basin shape from 2.25 to 26.59 for Region 1, 0.17 to 4,008.92 mi 2 and basin shape 2.04 to 26.89 for Region 2, and 2.12 to 2,177.58 mi 2 for Region 3. Annual peak data from streamgages were used to qualitatively assess the largest floods recorded at streamgages in Missouri since the 1915 water year. Based on existing streamgage data, the 1983 flood event was the largest flood event on record since 1915. The next five largest flood events, in descending order, took place in 1993, 1973, 2008, 1994 and 1915. Since 1915, five of six of the largest floods on record occurred from 1973 to 2012.

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USGS2014

An initial abstraction and constant loss model, and methods for estimating unit hydrographs, peak streamflows, and flood volumes for urban basins in Missouri

Streamflow data, basin characteristics, and rainfall data from 39 streamflow-gaging stations for urban areas in and adjacent to Missouri were used by the U.S. Geological Survey in cooperation with the Metropolitan Sewer District of St. Louis to develop an initial abstraction and constant loss model (a time-distributed basin-loss model) and a gamma unit hydrograph (GUH) for urban areas in Missouri. Study-specific methods to determine peak streamflow and flood volume for a given rainfall event also were developed. Distinct basin characteristics were evaluated and selected for use on the basis of their theoretical relation to flow, results from previous studies, and the ability to reliably measure the basin characteristic using digital datasets and geographic information system (GIS) technology. The key basin characteristics determined or computed for each of the 39 basins upstream from the streamflow-gaging stations were drainage area, percent impervious area, main-channel slope based on the 10- and 85-percent length method, percentage of the basin area in storage (lakes, ponds, reservoirs, wetlands), the composite Natural Resources Conservation Service curve number estimated from a combination of the soil type data and land-use characteristics, and the streamflow variability index developed for the recently completed study of low-flow regression in Missouri. Characteristics of spatial and temporal rainfall distribution came from the next generation weather radar (NEXRAD) network. Procedures were developed for this study to convert the variable radar sweep rate into a 5-minute total rainfall hyetograph using data from the radar bin at the centroid of a given basin. Additional characteristics determined for each storm on the basin included the 5-day and 14-day antecedent rainfall, estimated from the mean of daily rainfall values from various rain gages in the area. The database of observed rainfall and runoff events for the 39 basins upstream from the streamflow-gaging stations was analyzed to compute the optimal storm-specific initial abstraction and constant loss values, as well as the time to peak, peak streamflow, and shape factor values of the GUH. The optimal storm-specific values were used to develop a regional regression equation for initial abstraction; conversely, the constant loss was estimated not by regression but from either a generalized or specific regional mean value. The optimal storm-specific values of GUH time to peak, GUH peak streamflow, and GUH shape factor were used to develop regression equations for the GUH. The regression equations for the GUH initially were tested alone, and then were combined with the appropriate regional regression equation for initial abstraction and both the generalized regional and specific regional mean constant loss values. For the GUH regression equations, the interquartile range was substantially smaller than the range spanned by the minimum and maximum values, which indicates most of the errors have much smaller variation, and the minimum and maximum values may be extreme outliers. The central tendency of the regressed errors for peak streamflow and runoff hydrograph volume were both approximately zero, which implies a generally unbiased estimation of these values. The mean and median of the regressed errors for time to peak streamflow were both small but greater than zero, which implies the GUH regression equations create a hydrograph that has a peak that is later in time than observed. Specifically, the regressed times indicate an offset of about 10 minutes, on average, from observed. The mean and median of the regressed errors for widths of the runoff hydrograph at 50 and 75 percent were less than zero, which implies the GUH tends to slightly underestimate these widths compared to the observed. The appropriate regional initial abstraction regression equation was combined with both the generalized and the specific regional mean constant loss values and the GUH regression equations. Both the generalized regional mean constant loss and specific regional mean constant loss forms of the basin-loss model worked equally well to model the observed runoff hydrograph based on the error analysis, and neither model seems to make a consistently better approximation. Both initial abstraction and constant loss models combined with the GUH regression equations were further validated using several storms available after the start of the project in early 2011 with similar but consistently higher error results. If these methods are used in an urban area in Missouri other than those examined in this study, advice to the user is given to consider using the generalized regional mean values. If these methods are used in an urban area that is a subbasin of one of the basins in this study, advice to the user is given to consider using the specific regional mean values. The rainfall-runoff pairs from the storm-specific GUH analysis were further analyzed against various basin and rainfall characteristics to develop equations to estimate the peak streamflow and flood volume based on a quantity of rainfall on the basin.

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USGS2014

USGS geologic Mapping and karst research in the Ozark National Scenic Riverways, Missouri, USA

The Ozark National Scenic Riverways (ONSR) was created in 1964 to protect 134 miles of the Current River and its major tributary, the Jacks Fork, that are located in south-central Missouri (fig. 1). The park includes numerous large karst springs including Big Spring, by flow volume this is the largest spring in the National Park system. The National Park Service (NPS) administers a narrow, nearly continuous corridor of land adjacent to the two rivers. Base flow for the rivers is chiefly supplied by groundwater that has traveled through the karst landscape from as far as 38 miles away from the spring (Imes and Frederick, 2002). The watershed is vulnerable to pollution, but the area remains largely rural with few industries. The springs and rivers provide habitat for numerous aquatic species as well as recreational resources for floaters, fishermen, and campers. The ONSR is a major cave park with hundreds of known caves and diverse in-cave resources.

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USGS2013

Implementation of a non-lethal biopsy punch monitoring program for mercury in smallmouth bass, Micropterus dolomieu Lacepede, from the Eleven Point River, Missouri

A non-lethal biopsy method for monitoring mercury (Hg) concentrations in smallmouth bass ( Micropterus dolomieu ; smallmouth) from the Eleven Point River in southern Missouri USA was evaluated. A biopsy punch was used to remove a muscle tissue plug from the area immediately below the anterior dorsal fin of 31 smallmouth. An additional 35 smallmouth (controls) were held identically except that no tissue plug was removed. After sampling, all fish were held in a concrete hatchery raceway for 6 weeks. Mean survival at the end of the holding period was 97 % for both groups. Smallmouth length, weight and Fulton’s condition factor at the end of the holding period were also similar between plugged and non-plugged controls, indicating that the biopsy procedure had minimal impact on growth under these conditions. Tissue plug Hg concentrations were similar to smallmouth Hg data obtained in previous years by removing the entire fillet for analysis.

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USGS2013

Toxic exposure of songbirds to lead in the Southeast Missouri Lead Mining District

Mining and smelting in the Southeast Missouri Lead Mining District has caused widespread contamination of soils with lead (Pb) and other metals. Soils from three study sites sampled in the district contained from approximately 1,000–3,200 mg Pb/kg. Analyses of earthworms [33–4,600 mg Pb/kg dry weight (dw)] collected in the district showed likely high Pb exposure of songbirds preying on soil organisms. Mean tissue Pb concentrations in songbirds collected from the contaminated sites were greater (p < 0.05) than those in songbirds from reference sites by factors of 8 in blood, 13 in liver, and 23 in kidney. Ranges of Pb concentrations in livers (mg Pb/kg dw) were as follows: northern cardinal (Cardinalis cardinalis) = 0.11–3.0 (reference) and 1.3–30 (contaminated) and American robin (Turdus migratorius) = 0.43–8.5 (reference) and 7.6–72 (contaminated). Of 34 adult and juvenile songbirds collected from contaminated sites, 11 (32 %) had hepatic Pb concentrations that were consistent with adverse physiological effects, 3 (9 %) with systemic toxic effects, and 4 (12 %) with life-threatening toxic effects. Acid-fast renal intranuclear inclusion bodies, which are indicative of Pb poisoning, were detected in kidneys of two robins that had the greatest renal Pb concentrations (952 and 1,030 mg/kg dw). Mean activity of the enzyme delta-aminolevulinic acid dehydratase (ALAD) in red blood cells, a well-established bioindicator of Pb poisoning in birds, was decreased by 58–82 % in songbirds from the mining sites. We conclude that habitats within the mining district with soil Pb concentrations of ≥1,000 mg Pb/kg are contaminated to the extent that they are exposing ground-feeding songbirds to toxic concentrations of Pb.

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USGS2013

Foraging habitat for shorebirds in southeastern Missouri and its predicted future availability

Water management to protect agriculture in alluvial floodplains often conflicts with wildlife use of seasonal floodwater. Such is the case along the Mississippi River in southeastern Missouri where migrating shorebirds forage in shallow-flooded fields. I estimated the current availability of habitat for foraging shorebirds within the New Madrid and St. Johns Basins based on daily river elevations (1943–2009), under assumptions that shorebirds forage in open habitat with water depth <15 cm and use mudflats for 3 days after exposure. The area of shorebird foraging habitat, based on replicated 50-year random samples, averaged 975 ha per day during spring and 33 ha per day during fall. Adjustments to account for habitat quality associated with different water depths, duration of mudflat exposure, intra-seasonal availability, and state of agricultural crops, indicated the equivalent of 494 ha daily of optimal habitat during spring and 11 ha during fall. Proposed levees and pumps to protect cropland would reduce shorebird foraging habitat by 80 %: to 211 ha (108 optimal ha) per day during spring and 9 ha (<3 optimal ha) per day during fall. Alternative water management that allows natural flooding below a prescribed elevation would retain nearly all existing shorebird foraging habitat during fall and about 60 % of extant habitat during spring.

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USGS2013

Effects of historical lead–zinc mining on riffle-dwelling benthic fish and crayfish in the Big River of southeastern Missouri, USA

The Big River (BGR) drains much of the Old Lead Belt mining district (OLB) in southeastern Missouri, USA, which was historically among the largest producers of lead–zinc (Pb–Zn) ore in the world. We sampled benthic fish and crayfish in riffle habitats at eight sites in the BGR and conducted 56-day in situ exposures to the woodland crayfish (Orconectes hylas) and golden crayfish (Orconectes luteus) in cages at four sites affected to differing degrees by mining. Densities of fish and crayfish, physical habitat and water quality, and the survival and growth of caged crayfish were examined at sites with no known upstream mining activities (i.e., reference sites) and at sites downstream of mining areas (i.e., mining and downstream sites). Lead, zinc, and cadmium were analyzed in surface and pore water, sediment, detritus, fish, crayfish, and other benthic macro-invertebrates. Metals concentrations in all materials analyzed were greater at mining and downstream sites than at reference sites. Ten species of fish and four species of crayfish were collected. Fish and crayfish densities were significantly greater at reference than mining or downstream sites, and densities were greater at downstream than mining sites. Survival of caged crayfish was significantly lower at mining sites than reference sites; downstream sites were not tested. Chronic toxic-unit scores and sediment probable effects quotients indicated significant risk of toxicity to fish and crayfish, and metals concentrations in crayfish were sufficiently high to represent a risk to wildlife at mining and downstream sites. Collectively, the results provided direct evidence that metals associated with historical mining activities in the OLB continue to affect aquatic life in the BGR.

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USGS2013

Hydrologic connectivity of floodplains, northern Missouri: implications for management and restoration of floodplain forest communities in disturbed landscapes

Hydrologic connectivity between the channel and floodplain is thought to be a dominant factor determining floodplain processes and characteristics of floodplain forests. We explored the role of hydrologic connectivity in explaining floodplain forest community composition along streams in northern Missouri, USA. Hydrologic analyses at 20 streamgages (207–5827 km 2 area) document that magnitudes of 2-year return floods increase systematically with increasing drainage area whereas the average annual number and durations of floodplain-connecting events decrease. Flow durations above the active-channel shelf vary little with increasing drainage area, indicating that the active-channel shelf is in quasi-equilibrium with prevailing conditions. The downstream decrease in connectivity is associated with downstream increase in channel incision. These relations at streamflow gaging stations are consistent with regional channel disturbance patterns: channel incision increases downstream, whereas upstream reaches have either not incised or adjusted to incision by forming new equilibrium floodplains. These results provide a framework to explain landscape-scale variations in composition of floodplain forest communities in northern Missouri. Faust ( 2006 ) had tentatively explained increases of flood-dependent tree species, and decreases of species diversity, with a downstream increase in flood magnitude and duration. Because frequency and duration of floodplain-connecting events do not increase downstream, we hypothesize instead that increases in relative abundance of flood-dependent trees at larger drainage area result from increasing size of disturbance patches. Bank-overtopping floods at larger drainage area create large, open, depositional landforms that promoted the regeneration of shade-intolerant species. Higher tree species diversity in floodplains with small drainage areas is associated with non-incised floodplains that are frequently connected to their channels and therefore subject to greater effective hydrologic variability compared with downstream floodplains. Understanding the landscape-scale geomorphic and hydrologic controls on floodplain connectivity provides a basis for more effective management and restoration of floodplain forest communities.

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USGS2013

Integrating stations from the North America Gravity Database into a local GPS-based land gravity survey

The ability to augment local gravity surveys with additional gravity stations from easily accessible national databases can greatly increase the areal coverage and spatial resolution of a survey. It is, however, necessary to integrate such data seamlessly with the local survey. One challenge to overcome in integrating data from national databases is that these data are typically of unknown quality. This study presents a procedure for the evaluation and seamless integration of gravity data of unknown quality from a national database with data from a local Global Positioning System (GPS)-based survey. The starting components include the latitude, longitude, elevation and observed gravity at each station location. Interpolated surfaces of the complete Bouguer anomaly are used as a means of quality control and comparison. The result is an integrated dataset of varying quality with many stations having GPS accuracy and other reliable stations of unknown origin, yielding a wider coverage and greater spatial resolution than either survey alone.

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USGS2013

Effects of mining-associated lead and zinc soil contamination on native floristic quality

We assessed the quality of plant communities across a range of lead (Pb) and zinc (Zn) soil concentrations at a variety of sites associated with Pb mining in southeast Missouri, USA. In a novel application, two standard floristic quality measures, Mean Coefficient of Conservatism (Mean C) and Floristic Quality Index (FQI), were examined in relation to concentrations of Pb and Zn, soil nutrients, and other soil characteristics. Nonmetric Multidimensional Scaling and Regression Tree Analyses identified soil Pb and Zn concentrations as primary explanatory variables for plant community composition and indicated negative relationships between soil metals concentrations and both Mean C and FQI. Univariate regression also demonstrated significant negative relationships between metals concentrations and floristic quality. The negative effects of metals in native soils with otherwise relatively undisturbed conditions indicate that elevated soil metals concentrations adversely affect native floristic quality where no other human disturbance is evident.

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USGS2013

Mississippi River streamflow measurement techniques at St. Louis, Missouri

Streamflow measurement techniques of the Mississippi River at St. Louis have changed through time (1866–present). In addition to different methods used for discrete streamflow measurements, the density and range of discrete measurements used to define the rating curve (stage versus streamflow) have also changed. Several authors have utilized published water surface elevation (stage) and streamflow data to assess changes in the rating curve, which may be attributed to be caused by flood control and/or navigation structures. The purpose of this paper is to provide a thorough review of the available flow measurement data and techniques and to assess how a strict awareness of the limitations of the data may affect previous analyses. It is concluded that the pre-1930s discrete streamflow measurement data are not of sufficient accuracy to be compared with modern streamflow values in establishing long-term trends of river behavior.

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USGS2013

Rejuvenating Pre-GPS era geophysical surveys using The National Map

Old geophysical surveys [pre–Global Positioning System (GPS)] stand as valuable, largely untapped sources of scientific data. If data from these surveys were in a format that had reasonable accuracy, availability, and ease of access, they could be more widely used. In this paper, a pre-GPS survey is integrated into a modern geographic database, in this case, The National Map (TNM). The ultimate goal is to improve the accuracy, precision, provenance, and ease of access of the geospatial components of archived geophysical data. An unique set of data sources was assembled for this purpose. A comparison of these different data sources indicates that more than 80% of stations were positioned on The National Map within 15 m (horizontal) and 2 m (vertical) of the GPS-derived coordinates for each station within the survey. Although online database coordinate accuracy continues to improve, these results imply that web databases have already matured to a point where it is possible to integrate pre-GPS era survey coordinate data with reasonable positional accuracy.

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USGS2013

Microbial source tracking as a tool for TMDL development, Little Blue River in Independence, Missouri

The Little Blue River in Jackson County, Missouri has been listed by the Missouri Department of Natural Resources as impaired by bacteria for the protection of aquatic life and contact recreation from urban point and nonpoint sources. The Clean Water Act requires that a total maximum daily load (TMDL) for Escherichia coli (E. coli) be developed. Over a 5-year period, 108 base-flow, 87 stormflow, 48 fecal source, and 12 sewage influent samples were collected and analyzed for E. coli and Bacteroides general and host-associated microbial source tracking (MST) genetic markers. Less than half of the main-stem base-flow samples exceeded the E. coli state standard, whereas, all of the stormflow samples exceeded the standard during the recreation season (April through October). Both E. coli and MST markers were detected more frequently and at higher concentrations in stormflow samples. Only 14 percent of samples with E. coli detections greater than the Missouri state standard of 206 colonies per 100 milliliters had the human-associated Bacteroides marker as the only identified marker; therefore, Little Blue River TMDL development may require a broader scope beyond the municipal separate storm sewer system if bacteria sources are to be identified and addressed. Fecal samples showed a greater specificity with the human-associated marker than the dog- or ruminant-associated Bacteroides markers; however, false positives were at least one order of magnitude lower than true positives. MST data may be a useful tool for identifying probable sources of contamination and directing TMDL strategies.

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USGS2013

An expanded map of vegetation communities at Big Muddy National Fish and Wildlife Refuge

In 2012, a map of vegetation communities on Big Muddy National Fish and Wildlife Refuge was expanded based on interpretation of aerial photographs and field data. National Agricultural Imagery Program aerial photographs were used to identify distinct communities on previously unmapped refuge units and newly acquired parcels. Newly mapped polygons were then visited to adjust map boundaries, classify communities according to the National Vegetation Classification System, and quantify the abundance of dominant species and non-native, invasive species of concern to the refuge and other resource management agencies along the Missouri River. The expanded map now covers 6,136 hectares representing 33 community types, including 6 previously unmapped types. The full map includes 1,113 polygons, of which 627 are new, 21 are updated from the 2009 mapping effort, and 465 are unchanged from 2009. Mortality of primarily cottonwood stems, because of growing-season floods between 2008 and 2011, has reduced foliar cover of woody stems and created more open wooded communities. In herbaceous communities, dominance by herbaceous old fields has increased due to the inclusion of refuge units dominated by lands in recent agricultural production in the expanded map. Wetland community abundance has increased slightly due to recent flooding.

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