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Page 603, results 15051 - 15075

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Not all publications have extents, not all extents are completely accurate
A system design for implementing advanced feature descriptions for a map knowledge base
Matthew Wagner, Dalia E. Varanka, E. Lynn Usery
2020, Scientific Investigations Report 2019-5148
A prototype system to explore Linked Data that semantically integrates geospatial data in various formats from different publication sources with data from The National Map of the U.S. Geological Survey is presented. The focus is on accessing advanced feature descriptions for data from The National Map with data coreferenced from...
Evaluation of survey methods for colonial waterbirds at Chase Lake National Wildlife Refuge, North Dakota
Lawrence D. Igl, Alisa J. Bartos, Robert O. Woodward, Paulette Scherr, Marsha A. Sovada
2020, Open-File Report 2020-1008
Estimating the number of breeding pairs in a mixed-species waterbird colony is difficult because colonial waterbirds are vulnerable to human intrusion and their colonies are often in remote areas with limited access. We investigated methods to estimate the number of nests of waterbirds at a large, mixed-species colony at Chase...
A geospatially resolved wetland vulnerability index: Synthesis of physical drivers
Zafer Defne, Alfredo Aretxabaleta, Neil K. Ganju, Tarandeep S. Kalra, Daniel K. Jones, Kathryn Smith
2020, PLoS ONE (15)
Assessing wetland vulnerability to chronic and episodic physical drivers is fundamental for establishing restoration priorities. We synthesized multiple data sets from E.B Forsythe National Wildlife Refuge, New Jersey, to establish a wetland vulnerability metric that integrates a range of physical processes, regulatory information and physical/biophysical features. The geospatial data are based on aerial imagery,...
Multi-decadal patterns of vegetation succession after tundra fire on the Yukon-Kuskokwim Delta, Alaska
Gerald Frost, Rachel A. Loehman, Lisa Saperstein, Matthew J. Macander, Peter Nelson, David Paradis, Sue M. Natali
2020, Environmental Research Letters
Alaska’s Yukon-Kuskokwim Delta (YKD) is one of the warmest parts of the Arctic tundra biome and tundra fires are common in its upland areas. Here we combine field measurements, Landsat observations, and quantitative cover maps for tundra plant functional types (PFTs) to characterize multi-decadal succession and landscape change after fire in lichen-dominated upland tundra...
Numerical simulation of groundwater availability in central Moloka‘i, Hawai‘i
Delwyn S. Oki, John A. Engott, Kolja Rotzoll
2020, Scientific Investigations Report 2019-5150
Since the 1990s, increased chloride concentrations of water pumped from wells (much of which is used for drinking water) and the effects of withdrawals on groundwater-dependent ecosystems have led to concerns over groundwater availability on the island of Molokaʻi, Hawaiʻi. An improved understanding of the hydrologic effects of proposed groundwater...
Hawaiian hoary bat (Lasiurus cinereus semotus) acoustic monitoring at Hawaii Army National Guard (HIARNG) installations statewide
Kristina Montoya-Aiona, Corinna Pinzari, Robert W. Peck, Kevin W. Brinck, Frank J Bonaccorso
2020, Report
Acoustic sampling for occurrence of the endangered Hawaiian hoary bat (Lasiurus cinereus semotus) was conducted at 18 “long-term” acoustic monitoring stations on 12 Hawai‘i Army National Guard (HIARNG) installations across the islands of Hawai‘i, Maui, Moloka‘i, O‘ahu, and Kaua‘i between 2012 and 2018. Bats were confirmed as present at 10...
Assessing the spawning movement and habitat needs of riverine Neosho Smallmouth Bass
Shannon K. Brewer, Andrew Miller
2020, Cooperator Science Series CSS-145-2020
Stream fishes are vulnerable to a variety of natural and anthropogenic stressors. Information on fish movements and habitat use is essential to conserve and manage populations, particularly at the edges of distributions and novel habitats. The Neosho Smallmouth Bass Micropterus dolomieu velox is endemic to the southwestern Ozark Highlands ecoregion,...
Targeting aggregations of telemetered Lake Trout to increase gillnetting suppression efficacy
Jacob R. Williams, Christopher S. Guy, Todd M. Koel, Patricia E. Bigelow
2020, North American Journal of Fisheries Management (40) 225-231
Conserving Yellowstone Cutthroat Trout Oncorhynchus clarkii bouvieri by suppressing invasive Lake Trout Salvelinus namaycush in Yellowstone Lake is a high priority for Yellowstone National Park resource managers. Here, we tested whether targeting telemetered Lake Trout could increase the efficacy of Lake Trout suppression by gill netting. Mobile acoustic tracking surveys were performed to identify...
Climate relationships with increasing wildfire in the southwestern US from 1984 to 2015
Stephanie Mueller, Andrea E. Thode, Ellis Margolis, Larissa Yocom, Jesse M. Young, Jose M. Iniguez
2020, Forest Ecology and Management (460)
Over the last several decades in forest and woodland ecosystems of the southwestern United States, wildfire size and severity have increased, thereby increasing the vulnerability of these systems to type conversions, invasive species, and other disturbances. A combination of land use history and climate change is widely thought to be...
Multi-region assessment of pharmaceutical exposures and predicted effects in USA wadeable urban-gradient streams
Paul M. Bradley, Celeste A. Journey, Daniel T. Button, Daren M. Carlisle, B. J. Huffman, Sharon L. Qi, Kristin M. Romanok, Peter C. Van Metre
2020, PLoS (1) 1-25
Human-use pharmaceuticals in urban streams link aquatic-ecosystem health to human health. Pharmaceutical mixtures have been widely reported in larger streams due to historical emphasis on wastewater-treatment plant (WWTP) sources, with limited investigation of pharmaceutical exposures and potential effects in smaller headwater streams. In 2014–2017, the United States Geological Survey measured...
Lake Tahoe water monitoring and research activities
Ramon C. Naranjo
2020, Newsletter
Several decades ago, deteriorating water quality and clarity in Lake Tahoe prompted the initiation of environmental programs in the Lake Tahoe basin. Data on seasonal sediment loads from tributary streams, and nutrient loads from surrounding streams and groundwater aquifers, were needed to document the causes of this deterioration, the local...
Upper plate heterogeneity along the Southern Hikurangi Margin, New Zealand
Stuart Henrys, Donna Eberhart-Phillips, Dan Bassett, Rupert Sutherland, David Okaya, Martha Savage, Dominic Evanzia, Tim A. Stern, Hiroshi Sato, Kimihiro Mochizuki, Takaya Iwasaki, Eiji Kurashimo, Anya Seward, Aaron Wech
2020, Geophysical Research Letters (47)
Controlled and natural source seismic data are used to build a 3-D P wave model for southern North Island, New Zealand, where the Pacific Plate subducts beneath the Australian Plate at a rate of ~41 mm/year. Our analysis reveals an abrupt along-strike transition in overthrusting plate structure within Cook...
Passive seismic survey of sediment thickness, Dasht-e-Nawar basin, eastern Afghanistan
Thomas J. Mack
2020, Conference Paper, Military Geoscience
Exploration of water resources is needed for public supply, extraction of mineral resources, and economic development in Afghanistan. Remotely-sensed data are useful for identifying the general nature of surface sediments, however, “boots on the ground” geophysical surveys or drilling programs are needed to quantify the thickness of sediments or aquifers....
Cyanotoxin occurrence in large rivers of the United States
Jennifer L. Graham, Neil Dubrovsky, Guy M. Foster, Lindsey R. King, Keith Loftin, Barry Rosen, Erin Stelzer
2020, Inland Waters (10) 109-117
Cyanotoxins occur in rivers worldwide but are understudied in lotic ecosystems relative to lakes and reservoirs. Eleven large river sites located throughout the United States were sampled during June–September 2017 to determine the occurrence of cyanobacteria with known cyanotoxin-producing strains, cyanotoxin synthetase genes, and cyanotoxins. Chlorophyll-a concentrations spanned the range...
The community code verification exercise for simulating sequences of earthquakes and aseismic slip (SEAS)
Brittany Erickson, Junle Jiang, Michael Barall, Nadia Lapusta, Eric Dunham, Ruth A. Harris, Lauren Abrahams, Kali Allison, Jean-Paul Ampuero, Sylvain Barbot, Camilla Cattania, Ahmed Elbanna, Yuri Fialko, Benjamin Idini, Jeremy Kozdon, Valere Lambert, Yajing Liu, Yingdi Luo, Xiao Ma, Maricela Best McKay, Paul Segall, Pengsheng Shi, Martijn van den Ende, Mengjie Wei
2020, Seismological Research Letters (91) 874-890
Numerical simulations of sequences of earthquakes and aseismic slip (SEAS) have made great progress over past decades to address important questions in earthquake physics. However, significant challenges in SEAS modeling remain in resolving multiscale interactions between earthquake nucleation, dynamic rupture, and aseismic slip, and understanding physical factors controlling observables such as seismicity and ground deformation....
Identification of Acara (Cichlidae: Cichlasoma) established in Florida, USA
Robert H Robins, Mary E. Brown, Ryan A Crutchfield
2020, BioInvasions Records (9) 133-145
The Black Acara, Cichlasoma bimaculatum (Linnaeus, 1758), was first reported as introduced to Florida in 1965. Native to Venezuela, Guyana, Suriname, western French Guiana, and northern Brazil, the species is now distributed throughout Florida’s southern peninsula. Examination of live and preserved acara from Central Florida, heretofore identified as Black Acara, reveal the...
Field observations of wind waves in Upper Delaware Bay with living shorelines
Ling Zhu, Q. Chen, Hongqing Wang, William D. Capurso, L.M. Niemoczynski, Kelin Hu, Gregg Snedden
2020, Estuaries and Coasts (43) 739-755
Constructed oyster reefs (CORs) provide shore protections and habitats for fish and shellfish communities via wave energy attenuation. However, the processes and mechanism of CORs on wave attenuation remain unclear, thus limiting the effective assessment of CORs for shoreline protection. This paper presents results of a field investigation on wave...
Simulation modeling of complex climate, wildfire, and vegetation dynamics to address wicked problems in land management
Rachel A. Loehman, Robert E. Keane, Lisa M. Holsinger
2020, Frontiers in Forests and Global Change (3)
Complex, reciprocal interactions among climate, disturbance, and vegetation dramatically alter spatial landscape patterns and influence ecosystem dynamics. As climate and disturbance regimes shift, historical analogs and past empirical studies may not be entirely appropriate as templates for future management. The need for a better understanding of the potential impacts of climate changes on ecosystems...
Associations between riparian plant morphological guilds and fluvial sediment dynamics along the regulated Colorado River in Grand Canyon
Bradley J. Butterfield, Paul E. Grams, Laura E. Durning, Joseph Hazel, Emily C. Palmquist, Barbara Ralston, Joel B. Sankey
2020, River Research and Applications (36) 410-421
Effects of riparian vegetation on fluvial sediment dynamics depend on morphological traits of the constituent species. Determining the effects of different morphological guilds on sedimentation rates, as influenced by multiple aspects of dam operations, can help identify viable strategies for streamflow and vegetation management to achieve riparian resource goals. Plants...
Impacts of seagrass dynamics on the coupled long-term evolution of barrier-marsh-bay systems
Ian Reeves, Laura Moore, Evan Goldstein, Brad Murray, Joel A. Carr, Matthew Kirwan
2020, Journal of Geophysical Research: Biogeosciences (125)
Seagrass provides a wide range of economically and ecologically valuable ecosystem services, with shoreline erosion control often listed as a key service, but can also alter the sediment dynamics and waves within back-barrier bays. Here we incorporate seagrass dynamics into an existing barrier-marsh exploratory model, GEOMBEST++, to examine the coupled...
Potential duration of aftershocks of the 2020 southwestern Puerto Rico earthquake
Nicholas van der Elst, Jeanne L. Hardebeck, Andrew J. Michael
2020, Open-File Report 2020-1009
AbstractAftershocks (earthquakes clustered spatially and chronologically near the occurrence of a causative earthquake) are ongoing in southwestern Puerto Rico after a series of earthquakes, which include a magnitude 6.4 earthquake that occurred near Barrio Indios, Guayanilla, on January 7, 2020, and affected the surrounding area. This report estimates the expected...
Are elevation and open-water conversion of salt marshes connected?
Neil K. Ganju, Zafer Defne, Sergio Fagherazzi
2020, Geophysical Research Letters (47)
Salt marsh assessments focus on vertical metrics such as accretion or lateral metrics such as open-water conversion, without exploration of how the dimensions are related. We exploited a novel geospatial dataset to explore how elevation is related to the unvegetated-vegetated marsh ratio (UVVR), a lateral metric, across individual marsh “units”...
Fatty acid-based diet estimates suggest ringed seal remain the main prey of southern Beaufort Sea polar bears despite recent use of onshore food resources
Jennifer Bourque, Todd C. Atwood, George J. Divoky, Connie Stewart, Melissa A. McKinney
2020, Ecology and Evolution (10) 2093-2103
Polar bears (Ursus maritimus) from the southern Beaufort Sea (SB) subpopulation have traditionally fed predominantly upon ice‐seals; however, as the proportion of the subpopulation using onshore habitat has recently increased, foraging on land‐based resources, including remains of subsistence‐harvested bowhead whales (Balaena mysticetus) and colonial nesting seabirds has been observed. Adipose...
A brief introduction to seismic instrumentation: Where does my data come from?
Adam T. Ringler, Patrick Bastien
2020, Seismological Research Letters (91) 1074-1083
Modern seismology has been able to take advantage of several technological advances. These include feedback loops in the seismometer, specialized digitizers with absolute timing, and compression formats for storing data. While all of these advances have helped to improve the field, they can also leave newcomers a bit...
Paired stated preference methods for valuing management of white pine blister rust: order effects and outcome uncertainty
James Meldrum, Patricia A. Champ, Craig A. Bond, Anna Schoettle
2020, Journal of Forest Economics (35) 75-101
The literature on nonmarket valuation includes many examples of stated and revealed preference comparisons. However, comparisons within stated preference methods are sparse. Specifically, the literature provides few examples of pairing both a discrete choice experiment (CE) and a contingent valuation (CV) question within a single survey. This paper presents results...