Large shift in source of fine sediment in the upper Mississippi River
P. Belmont, K.B. Gran, S.P. Schottler, P.R. Wilcock, S.S. Day, C. Jennings, J.W. Lauer, E. Viparelli, J.K. Willenbring, D.R. Engstrom, G. Parker
2011, Environmental Science & Technology (45) 8804-8810
Although sediment is a natural constituent of rivers, excess loading to rivers and streams is a leading cause of impairment and biodiversity loss. Remedial actions require identification of the sources and mechanisms of sediment supply. This task is complicated by the scale and complexity of large watersheds as well as...
Short-term sandbar variability based on video imagery: Comparison between Time-Average and Time-Variance techniques
R.M.C. Guedes, L.J. Calliari, K. T. Holland, N.G. Plant, P.S. Pereira, F.N.A. Alves
2011, Marine Geology (289) 122-134
Time–exposure intensity (averaged) images are commonly used to locate the nearshore sandbar position (xb), based on the cross-shore locations of maximum pixel intensity (xi) of the bright bands in the images. It is not known, however, how the breaking patterns seen in Variance images (i.e. those created through standard deviation of pixel intensity...
In situ rates of sulfate reduction in response to geochemical perturbations
T.A. Kneeshaw, J.T. McGuire, Isabelle M. Cozzarelli, E.W. Smith
2011, Ground Water (49) 903-913
Rates of in situ microbial sulfate reduction in response to geochemical perturbations were determined using Native Organism Geochemical Experimentation Enclosures (NOGEEs), a new in situ technique developed to facilitate evaluation of controls on microbial reaction rates. NOGEEs function by first trapping a native microbial community in situ and then subjecting...
Fine-scale population structure and riverscape genetics of brook trout (Salvelinus fontinalis) distributed continuously along headwater channel networks
Yoichiro Kanno, Jason C. Vokoun, Benjamin H. Letcher
2011, Molecular Ecology (20) 3711-3729
Linear and heterogeneous habitat makes headwater stream networks an ideal ecosystem in which to test the influence of environmental factors on spatial genetic patterns of obligatory aquatic species. We investigated fine-scale population structure and influence of stream habitat on individual-level genetic differentiation in brook trout (Salvelinus fontinalis) by...
Unusual dominance by desert pupfish (Cyprinodon macularius) in experimental ponds within the Salton Sea Basin
Michael K. Saiki, Barbara A. Martin, Thomas W. Anderson
2011, Southwestern Naturalist (56) 385-392
In October 2006, months after shallow experimental ponds in the Salton Sea Basin were filled with water from the Alamo River and Salton Sea, fish were observed in several ponds, although inlets had been screened to exclude fish. During October 2007–November 2009, nine surveys were conducted using baited minnow traps...
Century-scale variability in global annual runoff examined using a water balance model
G.J. McCabe, D.M. Wolock
2011, International Journal of Climatology (31) 1739-1748
A monthly water balance model (WB model) is used with CRUTS2.1 monthly temperature and precipitation data to generate time series of monthly runoff for all land areas of the globe for the period 1905 through 2002. Even though annual precipitation accounts for most of the temporal and spatial variability in...
Standardized North American marsh bird monitoring protocol
Courtney J. Conway
2011, Waterbirds (34) 319-346
Little is known about the population status of many marsh-dependent birds in North America but recent efforts have focused on collecting more reliable information and estimates of population trends. As part of that effort, a standardized survey protocol was developed in 1999 that provided guidance for conducting marsh bird surveys...
Surface (sea floor) and near-surface (box cores) sediment mineralogy in Baffin Bay as a key to sediment provenance and ice sheet variations
John T. Andrews, D. D. Eberl
2011, Canadian Journal of Earth Sciences (48) 1307-1328
To better understand the glacial history of the ice sheets surrounding Baffin Bay and to provide information on sediment pathways, samples from 82 seafloor grabs and core tops, and from seven box cores were subjected to quantitative X-ray diffraction weight percent (wt.%) analysis of the <2 mm sediment fraction. The samples...
Dynamic habitat selection by two wading bird species with divergent foraging strategies in a seasonally fluctuating wetland
James M. Beerens, Dale E. Gawlik, Garth Herring, Mark I. Cook
2011, The Auk (128) 651-662
Seasonal and annual variation in food availability during the breeding season plays an influential role in the population dynamics of many avian species. In highly dynamic ecosystems like wetlands, finding and exploiting food resources requires a flexible behavioral response that may produce different population trends that vary with a species'...
Paleoenvironmental implications of taxonomic variation among δ15N values of chloropigments
Meytal B. Higgins, Felisa Wolfe-Simon, Rebecca S. Robinson, Yelun Qin, Mark A. Saito, Ann Pearson
2011, Geochimica et Cosmochimica Acta (75) 7351-7363
Natural variations in the ratios of nitrogen isotopes in biomass reflect variations in nutrient sources utilized for growth. In order to use δ15N values of chloropigments of photosynthetic organisms to determine the corresponding δ15N values of biomass – and by extension, surface waters – the isotopic offset between chlorophyll and...
A computer program for flow-log analysis of single holes (FLASH)
F. D. Day-Lewis, C. D. Johnson, Frederick L. Paillet, K. J. Halford
2011, Ground Water (49) 926-931
A new computer program, FLASH (Flow-Log Analysis of Single Holes), is presented for the analysis of borehole vertical flow logs. The code is based on an analytical solution for steady-state multilayer radial flow to a borehole. The code includes options for (1) discrete fractures and (2) multilayer aquifers. Given vertical...
Multivariate analyses with end-member mixing to characterize groundwater flow: Wind Cave and associated aquifers
Andrew J. Long, J.F. Valder
2011, Journal of Hydrology (409) 315-327
Principal component analysis (PCA) applied to hydrochemical data has been used with end-member mixing to characterize groundwater flow to a limited extent, but aspects of this approach are unresolved. Previous similar approaches typically have assumed that the extreme-value samples identified by PCA represent end members. The method presented herein is...
The GeoClaw software for depth-averaged flows with adaptive refinement
M.J. Berger, D.L. George, R.J. LeVeque, Kyle T. Mandli
2011, Advances in Water Resources (34) 1195-1206
Many geophysical flow or wave propagation problems can be modeled with two-dimensional depth-averaged equations, of which the shallow water equations are the simplest example. We describe the GeoClaw software that has been designed to solve problems of this nature, consisting of open source Fortran programs together with Python tools for...
Expansion rate and geometry of floating vegetation mats on the margins of thermokarst lakes, northern Seward Peninsula, Alaska, USA
A.D. Parsekian, Benjamin M. Jones, M. Jones, G. Grosse, Anthony K.M. Walter, L. Slater
2011, Earth Surface Processes and Landforms (36) 1889-1897
Investigations on the northern Seward Peninsula in Alaska identified zones of recent (<50 years) permafrost collapse that led to the formation of floating vegetation mats along thermokarst lake margins. The occurrence of floating vegetation mat features indicates rapid degradation of near‐surface permafrost and lake expansion. This paper reports on the recent...
Nearshore Tsunami Inundation Model Validation: Toward Sediment Transport Applications
Alex Apotsos, Mark Buckley, Guy Gelfenbaum, Bruce Jaffe, Deepak Vatvani
2011, Pure and Applied Geophysics (168) 2097-2119
Model predictions from a numerical model, Delft3D, based on the nonlinear shallow water equations are compared with analytical results and laboratory observations from seven tsunami-like benchmark experiments, and with field observations from the 26 December 2004 Indian Ocean tsunami. The model accurately predicts the magnitude and timing of the measured...
Fishes and tetrapods in the upper pennsylvanian (kasimovian) cohn coal member of the mattoon formation of illinois, United States: Systematics, paleoecology, and paleoenvironments
D. Carpenter, H. J. Falcon-Lang, M.J. Benton, W.J. Nelson
2011, Palaios (26) 639-657
A newly discovered vertebrate assemblage is reported from the Upper Pennsylvanian (mid- to upper Kasimovian) Cohn Coal Member of the Mattoon Formation of southeast Illinois, United States. Teeth, scales, and spines of xenacanth (Dicentrodus, Orthacanthus, Triodus, Xenacanthus) and euselachian (Sphenacanthus) sharks dominate the assemblage. Less common are the teeth, scales,...
Quantifying the hydrological responses to climate change in an intact forested small watershed in Southern China
G. Zhou, X. Wei, Y. Wu, Y. Huang, J. Yan, Dongxiao Zhang, Q. Zhang, J. Liu, Z. Meng, C. Wang, G. Chu, S. Liu, X. Tang, Xiuying Liu
2011, Global Change Biology (17) 3736-3746
Responses of hydrological processes to climate change are key components in the Intergovernmental Panel for Climate Change (IPCC) assessment. Understanding these responses is critical for developing appropriate mitigation and adaptation strategies for sustainable water resources management and protection of public safety. However, these responses are not well understood and little...
Integration of Palmer Drought Severity Index and remote sensing data to simulate wetland water surface from 1910 to 2009 in Cottonwood Lake area, North Dakota
Shengli Huang, Devendra Dahal, Claudia Young, Gyanesh Chander, Shuguang Liu
2011, Remote Sensing of Environment (115) 3377-3389
Spatiotemporal variations of wetland water in the Prairie Pothole Region are controlled by many factors; two of them are temperature and precipitation that form the basis of the Palmer Drought Severity Index (PDSI). Taking the 196 km2 Cottonwood Lake area in North Dakota as our pilot study site, we integrated PDSI, Landsat...
Surface-water nutrient conditions and sources in the United States Pacific Northwest
D.R. Wise, H.M. Johnson
2011, Journal of the American Water Resources Association (47) 1110-1135
The SPAtially Referenced Regressions On Watershed attributes (SPARROW) model was used to perform an assessment of surface-water nutrient conditions and to identify important nutrient sources in watersheds of the Pacific Northwest region of the United States (U.S.) for the year 2002. Our models included variables representing nutrient sources as well...
Overpressure generation by load transfer following shale framework weakening due to smectite diagenesis
R.W. Lahann, R.E. Swarbrick
2011, Geofluids (11) 362-375
Basin model studies which have addressed the importance of smectite conversion to illite as a source of overpressure in the Gulf of Mexico have principally relied on a single‐shale compaction model and treated the smectite reaction as only a fluid‐source term. Recent fluid pressure interpretation and shale petrology studies indicate...
A multi-agency nutrient dataset used to estimate loads, improve monitoring design, and calibrate regional nutrient SPARROW models
D. A. Saad, G. E. Schwarz, Dale M. Robertson, N.L. Booth
2011, Journal of the American Water Resources Association (47) 933-949
Stream‐loading information was compiled from federal, state, and local agencies, and selected universities as part of an effort to develop regional SPAtially Referenced Regressions On Watershed attributes (SPARROW) models to help describe the distribution, sources, and transport of nutrients in streams throughout much of the United States. After screening, 2,739...
Continuous fields of land cover for the conterminous United States using Landsat data: First results from the Web-Enabled Landsat Data (WELD) project
M.C. Hansen, Alexey Egorov, David P. Roy, P. Potapov, J. Ju, S. Turubanova, I. Kommareddy, Thomas R. Loveland
2011, Remote Sensing Letters (2) 279-288
Vegetation Continuous Field (VCF) layers of 30 m percent tree cover, bare ground, other vegetation and probability of water were derived for the conterminous United States (CONUS) using Landsat 7 Enhanced Thematic Mapper Plus (ETM+) data sets from the Web-Enabled Landsat Data (WELD) project. Turnkey approaches to land cover characterization were...
Response of spectral vegetation indices to soil moisture in grasslands and shrublands
Li Zhang, Lei Ji, Bruce K. Wylie
2011, International Journal of Remote Sensing (32) 5267-5286
The relationships between satellite-derived vegetation indices (VIs) and soil moisture are complicated because of the time lag of the vegetation response to soil moisture. In this study, we used a distributed lag regression model to evaluate the lag responses of VIs to soil moisture for grasslands and shrublands at Soil...
Coral skeletal carbon isotopes (δ13C and Δ14C) record the delivery of terrestrial carbon to the coastal waters of Puerto Rico
R.P. Moyer, A.G. Grottoli
2011, Coral Reefs (30) 791-802
Tropical small mountainous rivers deliver a poorly quantified, but potentially significant, amount of carbon to the world’s oceans. However, few historical records of land–ocean carbon transfer exist for any region on Earth. Corals have the potential to provide such records, because they draw on dissolved inorganic carbon (DIC) for calcification....
Digital hydrologic networks supporting applications related to spatially referenced regression modeling
J. W. Brakebill, D.M. Wolock, S.E. Terziotti
2011, Journal of the American Water Resources Association (47) 916-932
Digital hydrologic networks depicting surface‐water pathways and their associated drainage catchments provide a key component to hydrologic analysis and modeling. Collectively, they form common spatial units that can be used to frame the descriptions of aquatic and watershed processes. In addition, they provide the ability to simulate and route the...
