Sources of endocrine-disrupting compounds in North Carolina waterways: a geographic information systems approach
Dana K. Sackett, Crystal Lee Pow, Matthew J. Rubino, D.D. Aday, W. Gregory Cope, Seth W. Kullman, J. A. Rice, Thomas J. Kwak, LeRoy M. Law
2015, Environmental Toxicology and Chemistry (34) 437-445
The presence of endocrine-disrupting compounds (EDCs), particularly estrogenic compounds, in the environment has drawn public attention across the globe, yet a clear understanding of the extent and distribution of estrogenic EDCs in surface waters and their relationship to potential sources is lacking. The objective of the present study was to...
An early to mid-Pleistocene deep Arctic Ocean ostracode fauna with North Atlantic affinities
Lauren H. DeNinno, Thomas M. Cronin, J. Rodriquez-Lazaro, Alec R. Brenner
2015, Palaeogeography, Palaeoclimatology, Palaeoecology (419) 90-99
An early to middle Pleistocene ostracode fauna was discovered in sediment core P1-93-AR-23 (P23, 76.95°N, 155.07°W) from 951 meter water depth from the Northwind Ridge, western Arctic Ocean. Piston core P23 yielded more than 30,000 specimens and a total of about 30 species. Several early to mid-Pleistocene species in the genera Krithe,Echinocythereis, Pterygocythereis,...
Seasonal patterns in stream periphyton fatty acids and community benthic algal composition in six high quality headwater streams
Dale C. Honeyfield, Kelly O. Maloney
2015, Hydrobiologia (744) 35-47
Fatty acids are integral components of periphyton and differ among algal taxa. We examined seasonal patterns in periphyton fatty acids in six minimally disturbed headwater streams in Pennsylvania’s Appalachian Mountains, USA. Environmental data and periphyton were collected across four seasons for fatty acid and algal taxa content. Non-metric multidimensional scaling...
Influence of hardness on the bioavailability of silver to a freshwater snail after waterborne exposure to silver nitrate and silver nanoparticles
Tasha L. Stoiber, Marie Noele Croteau, Isabella Romer, Mila Tejamaya, Jamie R. Lead, Samuel N. Luoma
2015, Nanotoxicology (9) 918-927
The release of Ag nanoparticles (AgNPs) into the aquatic environment is likely, but the influence of water chemistry on their impacts and fate remains unclear. Here, we characterize the bioavailability of Ag from AgNO3 and from AgNPs capped with polyvinylpyrrolidone (PVP AgNP) and thiolated polyethylene glycol (PEG AgNP) in the...
Ephemeral stream reaches preserve the evolutionary and distributional history of threespine stickleback in the Santa Clara and Ventura River watersheds of southern California
Jonathan Q. Richmond, David K. Jacobs, Adam R. Backlin, Camm C. Swift, Chris Dellith, Robert N. Fisher
2015, Conservation Genetics (16) 85-101
Much remains to be understood about the evolutionary history and contemporary landscape genetics of unarmored threespine stickleback in southern California, where populations collectively referred to as Gasterosteus aculeatus williamsoni have severely declined over the past 70+ years and are now endangered. We used mitochondrial sequence and microsatellite data to assess...
Flow cytometric method for measuring chromatin fragmentation in fixed sperm from yellow perch (Perca flavescens)
Jill A. Jenkins, Rassa O. Draugelis-Dale, Alfred E. Pinkney, Luke R. Iwanowicz, Vicki Blazer
2015, Theriogenology (83) 920-931
Declining harvests of yellow perch, Perca flavescens, in urbanized watersheds of Chesapeake Bay have prompted investigations of their reproductive fitness. The purpose of this study was to establish a flow cytometric technique for DNA analysis of fixed samples sent from the field to provide reliable gamete quality measurements. Similar to the...
Magmatic gas emissions at Holocene volcanic features near Mono Lake, California, and their relation to regional magmatism
D. Bergfeld, William C. Evans, James F. Howle, Andrew G. Hunt
2015, Journal of Volcanology and Geothermal Research (292) 70-83
Silicic lavas have erupted repeatedly in the Mono Basin over the past few thousand years, forming the massive domes and coulees of the Mono Craters chain and the smaller island vents in Mono Lake. We report here on the first systematic study of magmatic CO2 emissions from these features, conducted during...
Differences between main-channel and off-channel food webs in the upper Mississippi River revealed by fatty acid profiles of consumers
James H. Larson, Michelle Bartsch, Steve Gutreuter, Brent C. Knights, Lynn Bartsch, William B. Richardson, Jonathan M. Vallazza, Michael T. Arts
2015, Inland Waters (5) 101-106
Large river systems are often thought to contain a mosaic of patches with different habitat characteristics driven by differences in flow and mixing environments. Off-channel habitats (e.g., backwater areas, secondary channels) can become semi-isolated from main-channel water inputs, leading to the development of distinct biogeochemical environments. Observations of adult bluegill...
Hillslope run-off thresholds with shrink–swell clay soils
Ryan D. Stewart, Majdi R. Abou Najm, David E. Rupp, John W. Lane Jr., Hamil C. Uribe, Jose Luis Arumi, John S. Selker
2015, Hydrological Processes (29) 557-571
Irrigation experiments on 12 instrumented field plots were used to assess the impact of dynamic soil crack networks on infiltration and run-off. During applications of intensity similar to a heavy rainstorm, water was seen being preferentially delivered within the soil profile. However, run-off was not observed until soil water content...
Anomalous solute transport in saturated porous media: Relating transport model parameters to electrical and nuclear magnetic resonance properties
Ryan D Swanson, Andrew Binley, Kristina Keating, Samantha France, Gordon Osterman, Frederick D. Day-Lewis, Kamini Singha
2015, Water Resources Research (51) 1264-1283
The advection-dispersion equation (ADE) fails to describe commonly observed non-Fickian solute transport in saturated porous media, necessitating the use of other models such as the dual-domain mass-transfer (DDMT) model. DDMT model parameters are commonly calibrated via curve fitting, providing little insight into the relation between effective parameters and physical properties...
Development of a new semi-analytical model for cross-borehole flow experiments in fractured media
Delphine Roubinet, James Irving, Frederick D. Day-Lewis
2015, Advances in Water Resources (76) 97-108
Analysis of borehole flow logs is a valuable technique for identifying the presence of fractures in the subsurface and estimating properties such as fracture connectivity, transmissivity and storativity. However, such estimation requires the development of analytical and/or numerical modeling tools that are well adapted to the complexity of the problem....
Sources of fine sediment stored in agricultural lowland streams, Midwest, USA
Jasmeet Lamba, Anita M. Thompson, K.G. Karthikeyan, Faith A. Fitzpatrick
2015, Geomorphology (236) 44-53
Agricultural activities can accelerate the offsite transport of productive soil from fields leading to stream water quality degradation. Identification of the nature and relative contribution of different sources to fine-grained sediment (e.g., silts, clays) in streams is important to effectively focus agricultural best management...
Inter-annual and spatial variability of Hamon potential evapotranspiration model coefficients
Gregory J. McCabe, Lauren E. Hay, Andy Bock, Steven L. Markstrom, R. Dwight Atkinson
2015, Journal of Hydrology (521) 389-394
Monthly calibrated values of the Hamon PET coefficient (C) are determined for 109,951 hydrologic response units (HRUs) across the conterminous United States (U.S.). The calibrated coefficient values are determined by matching calculated mean monthly Hamon PET to mean monthly free-water surface evaporation. For most locations and months the calibrated coefficients...
Tectonic activity as a significant source of crustal tetrafluoromethane emissions to the atmosphere: observations in groundwaters along the San Andreas Fault
Daniel A. Deeds, Justin T. Kulongoski, Jens Muhle, Ray F. Weiss
2015, Earth and Planetary Science Letters (412) 163-172
Tetrafluoromethane (CF4) concentrations were measured in 14 groundwater samples from the Cuyama Valley, Mil Potrero and Cuddy Valley aquifers along the Big Bend section of the San Andreas Fault System (SAFS) in California to assess whether tectonic activity in this region is a significant source of crustal CF4 to the...
Preliminary evaluation of an in vivo fluorometer to quantify algal periphyton biomass and community composition
Theodore D. Harris, Jennifer L. Graham
2015, Lake and Reservoir Management (31) 127-133
The bbe-Moldaenke BenthoTorch (BT) is an in vivo fluorometer designed to quantify algal biomass and community composition in benthic environments. The BT quantifies total algal biomass via chlorophyll a (Chl-a) concentration and may differentiate among cyanobacteria, green algae, and diatoms based on pigment fluorescence. To evaluate how BT measurements of...
Factors influencing CO2 and CH4 emissions from coastal wetlands in the Liaohe Delta, northeast China
Linda Olsson, Siyuan Ye, Xueyang Yu, Mengjie Wei, Ken W. Krauss, Hans Brix
2015, Biogeosciences Discussions (12) 3469-3503
Many factors are known to influence greenhouse gas emissions from coastal wetlands, but it is still unclear which factors are most important under field conditions when they are all acting simultaneously. The objective of this study was to assess the effects of water table, salinity, soil temperature and vegetation on...
Do shrubs reduce the adverse effects of grazing on soil properties?
David J. Eldridge, Genevieve Beecham, James B. Grace
2015, Ecohydrology (8) 1503-1513
Increases in the density of woody plants are a global phenomenon in drylands, and large aggregations of shrubs, in particular, are regarded as being indicative of dysfunctional ecosystems. There is increasing evidence that overgrazing by livestock reduces ecosystem functions in shrublands, but that shrubs may buffer the negative effects of...
Reducing nitrogen export from the corn belt to the Gulf of Mexico: agricultural strategies for remediating hypoxia
Eileen McLellan, Dale M. Robertson, Keith Schilling, Mark Tomer, Jill Kostel, Douglas G. Smith, Kevin King
2015, Journal of the American Water Resources Association (51) 263-289
SPAtially Referenced Regression on Watershed models developed for the Upper Midwest were used to help evaluate the nitrogen-load reductions likely to be achieved by a variety of agricultural conservation practices in the Upper Mississippi-Ohio River Basin (UMORB) and to compare these reductions to the 45% nitrogen-load reduction proposed to remediate...
A method for estimating the diffuse attenuation coefficient (KdPAR)from paired temperature sensors
Jordan S. Read, Kevin C. Rose, Luke A. Winslow, Emily K. Read
2015, Limnology and Oceanography: Methods (13) 53-61
A new method for estimating the diffuse attenuation coefficient for photosynthetically active radiation (KdPAR) from paired temperature sensors was derived. We show that during cases where the attenuation of penetrating shortwave solar radiation is the dominant source of temperature changes, time series measurements of water temperatures at multiple depths (z1 and z2)...
Suspended-sediment trapping in the tidal reach of an estuarine tributary channel
Maureen A. Downing-Kunz, David H. Schoellhamer
2015, Estuaries and Coasts (38) 2198-2212
Evidence of decreasing sediment supply to estuaries and coastal oceans worldwide illustrates the need for accurate and updated estimates. In the San Francisco Estuary (Estuary), recent research suggests a decrease in supply from its largest tributaries, implying the increasing role of smaller, local tributaries in sediment supply to this estuary....
Aquatic invertebrate food base for waterbirds at Wetland Reserve Program easements in the lower Mississippi Alluvial Valley
Jessica L. Tapp, Elisabeth B. Webb
2015, Wetlands (35) 183-192
Migratory waterbirds depend on invertebrates as a key source of dietary protein, but few studies have quantified aquatic invertebrates or their response to management on privately owned wetlands. Our objectives were to quantify the effects of wetland management provided through the Migratory Bird Habitat Initiative (MBHI) on invertebrate biomass, family...
The aging of America's reservoirs: In-reservoir and downstream physical changes and habitat implications
Kyle E. Juracek
2015, Journal of the American Water Resources Association (51) 168-184
Reservoirs are important for various purposes including flood control, water supply, power generation, and recreation. The aging of America's reservoirs and progressive loss of water storage capacity resulting from ongoing sedimentation, coupled with increasing societal needs, will cause the social, economic, environmental, and political importance of reservoirs to continually increase....
Genetic diversity and host specificity varies across three genera of blood parasites in ducks of the Pacific Americas Flyway
Andrew B. Reeves, Matthew M. Smith, Brandt W. Meixell, Joseph P. Fleskes, Andrew M. Ramey
2015, PLoS ONE (10)
Birds of the order Anseriformes, commonly referred to as waterfowl, are frequently infected by Haemosporidia of the genera Haemoproteus, Plasmodium, and Leucocytozoon via dipteran vectors. We analyzed nucleotide sequences of the Cytochrome b (Cytb) gene from parasites of these genera detected in six species of ducks from Alaska and California,...
Ecosystem-atmosphere exchange of CO2 in a temperate herbaceous peatland in the Sanjiang Plain of northeast China
Xiaoyan Zhu, Changchun Song, Christopher M. Swarzenski, Yuedong Guo, Xinhow Zhang, Jiaoyue Wang
2015, Ecological Engineering (75) 16-23
Northern peatlands contain a considerable share of the terrestrial carbon pool, which will be affected by future climatic variability. Using the static chamber technique, we investigated ecosystem respiration and soil respiration over two growing seasons (2012 and 2013) in a Carex lasiocarpa-dominated peatland in the Sanjiang Plain in China. We...
The role of water in unconventional in situ energy resource extraction technologies
Tanya J. Gallegos, Carleton R. Bern, Justin E. Birdwell, Seth S. Haines, Mark A. Engle
Satinder Ahuja, editor(s)
2015, Book chapter, Food, energy, and water: The chemistry connection
Global trends toward developing new energy resources from lower grade, larger tonnage deposits that are not generally accessible using “conventional” extraction methods involve variations of subsurface in situ extraction techniques including in situ oil shale retorting, hydraulic fracturing of petroleum reservoirs, and in situ recovery of uranium. Although these methods are...