A model of strength
Douglas H. Johnson, R.D. Cook
2013, Science (342) 192-193
In her AAAS News & Notes piece "Can the Southwest manage its thirst?" (26 July, p. 362), K. Wren quotes Ajay Kalra, who advocates a particular method for predicting Colorado River streamflow "because it eschews complex physical climate models for a statistical data-driven modeling approach." A preference for data-driven models...
Previously unrecognized regional structure of the Coastal Belt of the Franciscan Complex, northern California, revealed by magnetic data
Victoria E. Langenheim, Robert C. Jachens, Carl M. Wentworth, Robert J. McLaughlin
2013, Geosphere (9) 1-17
Magnetic anomalies provide surprising structural detail within the previously undivided Coastal Belt, the westernmost, youngest, and least-metamorphosed part of the Franciscan Complex of northern California. Although the Coastal Belt consists almost entirely of arkosic graywacke and shale of mainly Eocene age, new detailed aeromagnetic data show that it is pervasively...
Segmenting images automatically for granulometry and sedimentology: a martian case study
Suniti Karunatillake, Scott M. McLennan, Kenneth E. Herkenhoff, Jonathan M. Husch, Craig Hardgrove, J.R. Skok
2013, Icarus 408-417
In a companion work, we bridge the gap between mature segmentation software used in terrestrial sedimentology and emergent planetary segmentation with an original algorithm optimized to segment whole images from the Microscopic Imager (MI) of the Mars Exploration Rovers (MER). In this work, we compare its semi-automated outcome with manual photoanalyses using unconsolidated...
Phylogenetic conservatism in plant phenology
T. Jonathan Davies, Elizabeth M. Wolkovich, Nathan J. B. Kraft, Nicolas Salamin, Jenica M. Allen, Toby R. Ault, Julio L. Betancourt, Kjell Bolmgren, Elsa E. Cleland, Benjamin I. Cook, Theresa M. Crimmins, Susan J. Mazer, Gregory J. McCabe, Stephanie Pau, Jim Regetz, Mark D. Schwartz, Steven E. Travers
2013, Journal of Ecology (101) 1520-1530
Phenological events – defined points in the life cycle of a plant or animal – have been regarded as highly plastic traits, reflecting flexible responses to various environmental cues. The ability of a species to track, via shifts in phenological events, the abiotic environment through time might dictate its vulnerability to...
Network modularity reveals critical scales for connectivity in ecology and evolution
Robert J. Fletcher, Andre Revell, Brian E. Reichert, Wiley M. Kitchens, J. Dixon, James D. Austin
2013, Nature Communications (4) 1-7
For nearly a century, biologists have emphasized the profound importance of spatial scale for ecology, evolution and conservation. Nonetheless, objectively identifying critical scales has proven incredibly challenging. Here we extend new techniques from physics and social sciences that estimate modularity on networks to identify critical scales for movement and gene...
Geologic history of the summit of Axial Seamount, Juan de Fuca Ridge
David A. Clague, Brian M Dreyer, Jennifer B. Paduan, Julie F Martin, William W Chadwick, David W Caress, Ryan A Portner, Thomas P. Guilderson, Mary McGann, Hans Thomas, David A Butterfield, Robert W Embley
2013, Geochemistry, Geophysics, Geosystems (14) 4403-4443
Multibeam (1 m resolution) and side scan data collected from an autonomous underwater vehicle, and lava samples, radiocarbon-dated sediment cores, and observations of flow contacts collected by remotely operated vehicle were combined to reconstruct the geologic history and flow emplacement processes on Axial Seamount's summit and upper rift...
Rates and probable causes of freshwater tidal marsh failure, Potomac River Estuary, Northern Virginia, USA
Ronald J. Litwin, Joseph P. Smoot, Milan J. Pavich, Helaine W. Markewich, Erik T. Oberg, Brent W. Steury, Ben Helwig, Vincent L. Santucci, Geoffrey Sanders
2013, Wetlands (33) 1037-1061
Dyke Marsh, a distal tidal marsh along the Potomac River estuary, is diminishing rapidly in areal extent. This study documents Dyke Marsh erosion rates from the early-1860s to the present during pre-mining, mining, and post-mining phases. From the late-1930s to the mid-1970s, Dyke Marsh and the adjacent shallow riverbottom were...
Ability of matrix models to explain the past and predict the future of plant populations.
Kathryn McEachern, Elizabeth E. Crone, Martha M. Ellis, William F. Morris, Amanda Stanley, Timothy Bell, Paulette Bierzychudek, Johan Ehrlen, Thomas N. Kaye, Tiffany M. Knight, Peter Lesica, Gerard Oostermeijer, Pedro F. Quintana-Ascencio, Tamara Ticktin, Teresa Valverde, Jennifer I. Williams, Daniel F. Doak, Rengaian Ganesan, Andrea S. Thorpe, Eric S. Menges
2013, Conservation Biology (27) 968-978
Uncertainty associated with ecological forecasts has long been recognized, but forecast accuracy is rarely quantified. We evaluated how well data on 82 populations of 20 species of plants spanning 3 continents explained and predicted plant population dynamics. We parameterized stage-based matrix models with demographic data from individually marked plants and...
Estimated global nitrogen deposition using NO2 column density
Xuehe Lu, Hong Jiang, Xiuying Zhang, Jinxun Liu, Zhen Zhang, Jiaxin Jin, Ying Wang, Jianhui Xu, Miaomiao Cheng
2013, International Journal of Remote Sensing (34) 8893-8906
Global nitrogen deposition has increased over the past 100 years. Monitoring and simulation studies of nitrogen deposition have evaluated nitrogen deposition at both the global and regional scale. With the development of remote-sensing instruments, tropospheric NO2 column density retrieved from Global Ozone Monitoring Experiment (GOME) and Scanning Imaging Absorption...
Effects of dreissenids on monitoring and management of fisheries in western Lake Erie
Martin A. Stapanian, Patrick M. Kocovsky
2013, Book chapter, Quagga and zebra mussels: biology, impacts, and control
Water clarity increased in nearshore areas of western Lake Erie by the early-1990s mainly as a result of the filtering activities of dreissenid mussels (Dreissena spp.), which invaded in the mid-1980s. We hypothesized that increased water clarity would result in greater trawl avoidance and thus reduced ability to capture fish...
Geographic setting influences Great Lakes beach microbiological water quality
Sheridan K. Haack, Lisa R. Fogarty, Erin A. Stelzer, Lori M. Fuller, Angela K. Brennan, Natasha M. Isaacs, Heather E. Johnson
2013, Environmental Science & Technology (47) 12054-12063
Understanding of factors that influence Escherichia coli (EC) and enterococci (ENT) concentrations, pathogen occurrence, and microbial sources at Great Lakes beaches comes largely from individual beach studies. Using 12 representative beaches, we tested enrichment cultures from 273 beach water and 22 tributary samples for EC, ENT, and genes indicating the...
How old is the Isthmus of Panama?
Anthony G Coates, Robert F. Stallard
2013, Bulletin of Marine Science (89) 801-813
The Standard Model of the formation of the Isthmus of Panama proposes that final closure occurred at 4–3 Ma. The model is based on evidence from studies of marine stratigraphy, fossil sequences, divergent molecular phylogenies, the timing of the Great American Biological Interchange (GABI), and proxies for marine paleosalinity, paleobathymetry,...
Variability and trends in irrigated and non-irrigated croplands in the central U.S
Jesslyn F. Brown, Md Shahriar Pervez
2013, Conference Paper, Information for sustainable agriculture, International Conference on Agro-Geoinformatics, 2nd, Fairfax, Va., 12–16 August 2013, Proceedings
Over 23 million hectares (233 thousand km2) of U.S. croplands are irrigated and there was an overall net expansion of 522 thousand hectares nationally from 2002 to 2007. Most of this expansion occurred across the High Plains Aquifer (HPA) in the central Great Plains. Until recently, there has been a...
The Hyper-Envelope Modeling Interface (HEMI): A Novel Approach Illustrated Through Predicting Tamarisk (Tamarix spp.) Habitat in the Western USA
Jim Graham, Nick Young, Catherine S. Jarnevich, Greg Newman, Paul Evangelista, Thomas J. Stohlgren
2013, Environmental Management (52) 929-938
Habitat suitability maps are commonly created by modeling a species’ environmental niche from occurrences and environmental characteristics. Here, we introduce the hyper-envelope modeling interface (HEMI), providing a new method for creating habitat suitability models using Bezier surfaces to model a species niche in environmental space. HEMI allows modeled surfaces to...
Statistical mapping of zones of focused groundwater/surface-water exchange using fiber-optic distributed temperature sensing
Kisa Mwakanyamale, Frederick D. Day-Lewis, Lee D. Slater
2013, Water Resources Research (49) 6979-6984
Fiber-optic distributed temperature sensing (FO-DTS) increasingly is used to map zones of focused groundwater/surface-water exchange (GWSWE). Previous studies of GWSWE using FO-DTS involved identification of zones of focused GWSWE based on arbitrary cutoffs of FO-DTS time-series statistics (e.g., variance, cross-correlation between temperature and stage, or spectral power). New approaches are...
Distribution of extant populations of Quadrula mitchelli (false spike)
Charles R. Randklev, Eric Tsakiris, Robert G. Howells, Julie Groce, Matthew S. Johnson, Joseph Bergmann, Clint Robertson, Andy Blair, Brad Littrell, Nathan Johnson
2013, Ellipsaria (15) 18-21
The False Spike, Quadrula mitchelli (Simpson 1896), is a rare species of mussel endemic to Central Texas and the Rio Grande drainage (Howells 2010). This species was thought to have been extinct until the discovery of several live individuals in the Guadalupe River and a fresh dead individual in the...
Lake shoreline in the contiguous United States: Quantity, distribution and sensitivity to observation resolution
Luke A. Winslow, Jordan S. Read, Paul C. Hanson, Emily H. Stanley
2013, Freshwater Biology
1. Quantifying lake biogeochemical processing at broad spatial scales requires that we scale processes along with physical metrics. Past work has primarily scaled lentic processes using estimates of lake surface area. However, many processes important to lakes, such as material, energy and biological fluxes and biogeochemical cycling, scale with lake...
The state of human dimensions capacity for natural resource management: needs, knowledge, and resources
Natalie R. Sexton, Kirsten M. Leong, Brad J. Milley, Melinda M. Clarke, Tara L. Teel, Mark A. Chase, Alia M. Dietsch
2013, The George Wright Forum (30) 142-153
The social sciences have become increasingly important in understanding natural resource management contexts and audiences, and are essential in design and delivery of effective and durable management strategies. Yet many agencies and organizations do not have the necessary resource management. We draw on the textbook definition of HD: how and...
Recent changes in successional state of the deep-water fish communities of Lakes Michigan, Huron, and Ontario and management implications
Randy L. Eshenroder, Brian F. Lantry
William W. Taylor, Abigail Lynch, Nancy J. Leonard, editor(s)
2013, Book chapter, Great Lakes fisheries policy and management: A binational perspective
No abstract available....
It's time for bold new approaches to link delta science and policymaking
James E. Cloern, Ellen Hanak
2013, San Francisco Estuary and Watershed Science (11)
California’s Sacramento–San Joaquin Delta is widely recognized as a highly damaged ecosystem. The Delta is also emblematic of a growing sense worldwide that society needs to do a better job of using scientific knowledge to guide conservation and resource management policies. Fortunately, we now have an unprecedented opportunity to get it right in building...
Seasonal circulation over the Catalan inner-shelf (northwest Mediterranean Sea)
Manel Grifoll, Alfredo L. Aretxabaleta, Josep L. Pelegri, Manuel Espino, John C. Warner, Agustin Sanchez-Arcilla
2013, Journal of Geophysical Research C: Oceans (118) 5844-5857
This study characterizes the seasonal cycle of the Catalan inner-shelf circulation using observations and complementary numerical results. The relation between seasonal circulation and forcing mechanisms is explored through the depth-averaged momentum balance, for the period between May 2010 and April 2011, when velocity observations were partially available. The monthly-mean along-shelf...
Alternative ways of using field-based estimates to calibrate ecosystem models and their implications for carbon cycle studies
Yujie He, Qianlai Zhuang, David McGuire, Yaling Liu, Min Chen
2013, Journal of Geophysical Research: Biogeosciences (118) 983-993
Model-data fusion is a process in which field observations are used to constrain model parameters. How observations are used to constrain parameters has a direct impact on the carbon cycle dynamics simulated by ecosystem models. In this study, we present an evaluation of several options for the use of observations...
Parasites as prey in aquatic food webs: implications for predator infection and parasite transmission
David W. Thieltges, Per-Arne Amundsen, Ryan F. Hechinger, Pieter T.J. Johnson, Levin D. Lafferty, Kim N. Mouritsen, Daniel L. Preston, Karsten Reise, C. Dieter Zander, Robert Poulin
2013, Oikos (122) 1473-1482
While the recent inclusion of parasites into food-web studies has highlighted the role of parasites as consumers, there is accumulating evidence that parasites can also serve as prey for predators. Here we investigated empirical patterns of predation on parasites and their relationships with parasite transmission in eight topological food webs...
Vs30 and spectral response from collocated shallow, active- and passive-source Vs data at 27 sites in Puerto Rico
Jack K. Odum, William J. Stephenson, Robert A. Williams, Christa von Hillebrandt-Andrade
2013, Bulletin of the Seismological Society of America (103) 2709-2728
Shear‐wave velocity (VS) and time‐averaged shear‐wave velocity to 30 m depth (VS30) are the key parameters used in seismic site response modeling and earthquake engineering design. Where VS data are limited, available data are often used to develop and refine map‐based proxy models of VS30 for predicting ground‐motion intensities. In...
Temporal, spatial, and body size effects on growth rates of loggerhead sea turtles (Caretta caretta) in the Northwest Atlantic
Karen A. Bjorndal, Barbara A. Schroeder, Allen M. Foley, Blair E. Witherington, Michael Bresette, David Clark, Richard M. Herren, Michael D. Arendt, Jeffrey R. Schmid, Anne B. Meylan, Peter A. Meylan, Jane A. Provancha, Kristen M. Hart, Margaret M. Lamont, Raymond R. Carthy, Alan B. Bolten
2013, Marine Biology (160) 2711-2721
In response to a call from the US National Research Council for research programs to combine their data to improve sea turtle population assessments, we analyzed somatic growth data for Northwest Atlantic (NWA) loggerhead sea turtles (Caretta caretta) from 10 research programs. We assessed growth dynamics over wide ranges of...
