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2017

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Full-Text Articles in Other Earth Sciences

Structural Analysis Of The Northwest Wind Mountain Quadrangle, New Mexico: Proterozoic Shearing To Cenozoic Brittle Faulting In The Burro Mountains, Jensen Kohl Angelloz Dec 2017

Structural Analysis Of The Northwest Wind Mountain Quadrangle, New Mexico: Proterozoic Shearing To Cenozoic Brittle Faulting In The Burro Mountains, Jensen Kohl Angelloz

Electronic Theses and Dissertations

Preliminary investigation of the Bullard Peak metamorphic series (BPMS) in the northwestern Wind Mountain quadrangle within the Burro Mountains of southwestern New Mexico suggests a possible previously unidentified shear zone, prompting detailed (1:12,000) geologic mapping and collection of structural data. The study area has a complex tectonic history, including 1) ~1.65 Ga metamorphism during accretion of the Mazatzal terrane to Laurentia’s southern margin; 2) ~1.4 Ga intrusion of Granite and Rhyolite Province granitoids; 3) significant uplift during the formation of the Ancestral Rockies (~300 Ma) and the Rocky Mountains (~70-50 Ma); and 4) inversion tectonics with reactivation of compressional faults …


Ordovician Continental Paleogeography And Paleoenvironment For The Michigan Basin From Paleomagnetic Analysis, Michelle Macrae Dec 2017

Ordovician Continental Paleogeography And Paleoenvironment For The Michigan Basin From Paleomagnetic Analysis, Michelle Macrae

Electronic Thesis and Dissertation Repository

This study investigates the paleomagnetic record of Paleozoic rocks from two Michigan basin localities in southwestern Ontario to help close the 40 myr gap in Paleozoic paleomagnetic data. Paleomagnetic data from the Queenston (Upper Ordovician) formation consistently exhibits easily removed viscous remanence, an intermediate and a high temperature component consistent with the unblocking temperatures of magnetite and hematite respectively. Alternating-field and thermal demagnetization in 16–20 steps up to 670º C typically reveal a southeastern, shallow up direction removed from magnetite, and a southwestern, steep up direction removed from hematite. A Late Paleozoic overprint was preserved in the magnetite and a …


The Impact Of Reduced Arctic Sea Ice Extent On Cryospheric Snowfall, Alexander Carne Dec 2017

The Impact Of Reduced Arctic Sea Ice Extent On Cryospheric Snowfall, Alexander Carne

Department of Earth and Atmospheric Sciences: Dissertations, Theses, and Student Research

Satellite observations show that sea ice extent in the Arctic has been declining from 1979 through present day, reaching record minimum extents in 2007 and 2012. Reduced sea ice extent allows for greater expanses of open water to interact with the Arctic atmosphere, potentially leading to changes in the Arctic climate. The greatest declines in Arctic sea ice extent have occurred in summer and autumn. During these seasons, it is likely that the decrease in Arctic sea ice extent led to an increase in atmospheric sensible and latent heat fluxes, possibly leading to increases in Arctic temperature and moisture. Increases …


Deriving Landscape-Scale Vegetation Cover And Aboveground Biomass In A Semi-Arid Ecosystem Using Imaging Spectroscopy, Andrew Poley Dec 2017

Deriving Landscape-Scale Vegetation Cover And Aboveground Biomass In A Semi-Arid Ecosystem Using Imaging Spectroscopy, Andrew Poley

Boise State University Theses and Dissertations

Environmental disturbances in semi-arid ecosystems have highlighted the need to monitor current and future vegetation conditions across the landscape. Imaging spectroscopy provide the necessary information to derive vegetation characteristics at high-spatial resolutions across large geographic areas. The work of this thesis is divided into two sections focused on using imaging spectroscopy to estimate and classify vegetation cover, and approximate aboveground biomass in a semi-arid ecosystem.

The first half of this thesis assesses the ability of imaging spectroscopy to derive vegetation classes and their respective cover across large environmental gradients and ecotones often associated with semi-arid ecosystems. Optimal endmember selection and …


Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard Dec 2017

Geophysical Delineation Of Megaporosity And Fluid Migration Pathways For Geohazard Characterization Within The Delaware Basin, Culberson County, Texas, Jonathan David Woodard

Electronic Theses and Dissertations

ABSTRACT

Differential dissolution of gypsum karst within the Delaware Basin poses a significant threat to infrastructure that society depends on. The study area is located in Culberson County, Texas and traverses a distance of approximately 54 kilometers along RM 652 within the Gypsum Plain which is situated on the northern margin of the Chihuahua Desert and includes outcrops of Castile and Rustler strata that host karst geohazards. Regions of karst geohazard potential have been physically surveyed proximal to the study area in evaporites throughout the Castile Formation outcrop; minimal hazards, in comparison to the Castile Formation, have been documented in …


The Impact Of Fe-Ti Oxide Concentration On The Structural Ridgity Of The Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge, Daniel Winkler Dec 2017

The Impact Of Fe-Ti Oxide Concentration On The Structural Ridgity Of The Lower Oceanic Crust, Atlantis Bank, Southwest Indian Ridge, Daniel Winkler

Master's Theses

Fe-Ti oxides are important components of oceanic core complexes (OCC) formed at slow-spreading mid-ocean ridges since Fe-Ti oxides are more susceptible to crystal-plastic deformation than silicate minerals. This study investigated the predicted relationship between the presence and concentration of Fe-Ti oxides and the presence and intensity of crystal-plastic deformation in gabbroic samples from Atlantis Bank, Southwest Indian Ridge (SWIR). Atlantis Bank is an oceanic core complex that formed through the exhumation of lower oceanic crust along a detachment fault. OCCs form along slow-spreading ridges and are characterized by the complex interactions between magmatism and lithospheric extension, thus making these complexes …


Quaternary Sea-Level History And The Origin Of The Northernmost Coastal Aeolianites In The Americas: Channel Islands National Park, California, Usa, Daniel R. Muhs, Jeffrey S. Pigati, R. Randall Schumann, Gary L. Skipp, Naomi Porat, Stephen B. Devogel Nov 2017

Quaternary Sea-Level History And The Origin Of The Northernmost Coastal Aeolianites In The Americas: Channel Islands National Park, California, Usa, Daniel R. Muhs, Jeffrey S. Pigati, R. Randall Schumann, Gary L. Skipp, Naomi Porat, Stephen B. Devogel

United States Geological Survey: Staff Publications

Along most of the Pacific Coast of North America, sand dunes are dominantly silicate-rich. On the California Channel Islands, however, dunes are carbonate-rich, due to high productivity offshore and a lack of dilution by silicate minerals. Older sands on the Channel Islands contain enough carbonate to be cemented into aeolianite. Several generations of carbonate aeolianites are present on the California Channel Islands and represent the northernmost Quaternary coastal aeolianites on the Pacific Coast of North America. The oldest aeolianites on the islands may date to the early Pleistocene and thus far have only been found on Santa Cruz Island. Aeolianites …


Late Quaternary Uplift Along The North America-Caribbean Plate Boundary: Evidence From The Sea Level Record Of Guantanamo Bay, Cuba, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons, Robert B. Halley Nov 2017

Late Quaternary Uplift Along The North America-Caribbean Plate Boundary: Evidence From The Sea Level Record Of Guantanamo Bay, Cuba, Daniel R. Muhs, Eugene S. Schweig, Kathleen R. Simmons, Robert B. Halley

United States Geological Survey: Staff Publications

The tectonic setting of the North America-Caribbean plate boundary has been studied intensively, but some aspects are still poorly understood, particularly along the Oriente fault zone. Guantanamo Bay, southern Cuba, is considered to be on a coastline that is under a transpressive tectonic regime along this zone, and is hypothesized to have a low uplift rate. We tested this by studying emergent reef terrace deposits around the bay. Reef elevations in the protected, inner part of the bay are ~11e12 m and outercoast, wave-cut benches are as high as ~14 m. Uranium-series analyses of corals yield ages ranging from ~133 …


How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux Nov 2017

How Dredge Pits Evolve Over Time: A Look At Their Geomorphologic Evolution And Infilling Processes, Patrick Robichaux

LSU Master's Theses

As coastal environments become more susceptible to land loss through accelerating sea level rise and subsidence, new restoration methods harnessing borrowed sediment are more valuable than ever. Mud-capped dredge pits (MCDPs) are a relatively new source of restoration-quality sediment that has only recently been utilized for beach and barrier island restorations in Louisiana. Because MCDPs have been in use for less than two decades in only a handful sites, little is understood about their evolution over decadal timescales. To improve our understanding of MCDPs after they are dredged, we have conducted a suite of geophysical surveys including bathymetry, sidescan sonar, …


Evaluating Satellite And Supercomputing Technologies For Improved Coastal Ecosystem Assessments, Matthew James Mccarthy Nov 2017

Evaluating Satellite And Supercomputing Technologies For Improved Coastal Ecosystem Assessments, Matthew James Mccarthy

USF Tampa Graduate Theses and Dissertations

Water quality and wetlands represent two vital elements of a healthy coastal ecosystem. Both experienced substantial declines in the U.S. during the 20th century. Overall coastal wetland cover decreased over 50% in the 20th century due to coastal development and water pollution. Management and legislative efforts have successfully addressed some of the problems and threats, but recent research indicates that the diffuse impacts of climate change and non-point source pollution may be the primary drivers of current and future water-quality and wetland stress. In order to respond to these pervasive threats, traditional management approaches need to adopt modern …


Flash Droughts: A Review And Assessment Of The Challenges Imposed By Rapid-Onset Droughts In The United States, Jason A. Otkin, Mark Svoboda, Eric D. Hunt, Trent W. Ford, Martha C. Anderson, Christopher Hain, Jeffrey B. Basara Nov 2017

Flash Droughts: A Review And Assessment Of The Challenges Imposed By Rapid-Onset Droughts In The United States, Jason A. Otkin, Mark Svoboda, Eric D. Hunt, Trent W. Ford, Martha C. Anderson, Christopher Hain, Jeffrey B. Basara

Drought Mitigation Center: Faculty Publications

No abstract provided.


A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin Nov 2017

A Study Of Marine Terrace Formation Along The California Central Coast, Mary C. Devlin

Natural Resources Management and Environmental Sciences

Marine terrace formation is in many instances attributed to wave action, and shore platforms are often called “wave-cut”. However, alternative models for marine terrace formation suggest that other types of physical and chemical weathering have a more central role in the formation of marine terraces than is widely acknowledged. Roering and Retallack (2012) concluded that the roles of subaerial physical and chemical weathering are significant, and played a major role in the formation of the terraces. In this study, weathering of beach cliffs and shore platforms associated with marine terraces at eight sites in two different locations along the central …


The Geochemistry Of Loess: Asian And North American Deposits Compared, Daniel R. Muhs Oct 2017

The Geochemistry Of Loess: Asian And North American Deposits Compared, Daniel R. Muhs

United States Geological Survey: Staff Publications

Loess is widely distributed over Asia and North America and constitutes one of the most important surficial deposits that serve as terrestrial records of the Quaternary. The oldest Pleistocene loess in China is likely ∼2.6 Ma, thus spanning much or all of the Pleistocene. In North America, most loess is no older than the penultimate glacial period, with the exception of Alaska, where the record may go back to ∼3.0 Ma. On both continents, loess deposits date primarily to glacial periods, and interglacial or interstadial periods are represented by paleosols. Both glacial and non-glacial sources of silts that comprise the …


What Controls Variation In Carbon Use Efficiency Among Amazonian Tropical Forests?, Christopher E. Doughty, Gregory R. Goldsmith, Nicolas Raab, Cecile A. J. Girardin, Filio Farfan-Amezquita, Walter Huaraca-Huasco, Javier E. Silva-Espejo, Alejandro Araujo-Murakami, Antonio C. L. Da Costa, Wanderley Rocha, David Galbraith, Patrick Meir, Dan B. Metcalfe, Yadvinder Malhi Oct 2017

What Controls Variation In Carbon Use Efficiency Among Amazonian Tropical Forests?, Christopher E. Doughty, Gregory R. Goldsmith, Nicolas Raab, Cecile A. J. Girardin, Filio Farfan-Amezquita, Walter Huaraca-Huasco, Javier E. Silva-Espejo, Alejandro Araujo-Murakami, Antonio C. L. Da Costa, Wanderley Rocha, David Galbraith, Patrick Meir, Dan B. Metcalfe, Yadvinder Malhi

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Why do some forests produce biomass more efficiently than others? Variations in Carbon Use Efficiency (CUE: total Net Primary Production (NPP)/ Gross Primary Production (GPP)) may be due to changes in wood residence time (Biomass/NPPwood), temperature, or soil nutrient status. We tested these hypotheses in 14, one ha plots across Amazonian and Andean forests where we measured most key components of net primary production (NPP: wood, fine roots, and leaves) and autotrophic respiration (Ra; wood, rhizosphere, and leaf respiration). We found that lower fertility sites were less efficient at producing biomass and had higher rhizosphere respiration, …


Droughtscape- Fall 2017, National Drought Mitigation Center Oct 2017

Droughtscape- Fall 2017, National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

CONTENTS

Drought worsens in northern Great Plains............. 2

Drought takes toll on ag, livestock................ 4

Study examines ag advisors’ views on climate change............... 5

New drought definition could lead to better preparation.............. 6

McCook takes big steps toward drought readiness.............8

Group hopes to map drought planning process for Korea............9

South African researcher working to forecast drought.................. 10

Cultivating drought preparedness in South Africa.............. 12


Do Advisors Perceive Climate Change As An Agricultural Risk? An In-Depth Examination Of Midwestern U.S. Ag Advisors’ Views On Drought, Climate Change, And Risk Management, Sarah P. Church, Michael Dunn, Nicholas Babin, Amber Saylor Mase, Tonya Haigh, Linda Stalker Prokopy Oct 2017

Do Advisors Perceive Climate Change As An Agricultural Risk? An In-Depth Examination Of Midwestern U.S. Ag Advisors’ Views On Drought, Climate Change, And Risk Management, Sarah P. Church, Michael Dunn, Nicholas Babin, Amber Saylor Mase, Tonya Haigh, Linda Stalker Prokopy

Drought Mitigation Center: Faculty Publications

Through the lens of the Health Belief Model and Protection Motivation Theory, we analyzed interviews of 36 agricultural advisors in Indiana and Nebraska to understand their appraisals of climate change risk, related decision making processes and subsequent risk management advice to producers. Most advisors interviewed accept that weather events are a risk for US Midwestern agriculture; however, they are more concerned about tangible threats such as crop prices. There is not much concern about climate change among agricultural advisors. Management practices that could help producers adapt to climate change were more likely to be recommended by conservation and Extension advisors, …


Agricultural Responses To Climate Change: A Study Of Adaptive Farming Methods In Kizanda Village, Bailey Smith-Helman Oct 2017

Agricultural Responses To Climate Change: A Study Of Adaptive Farming Methods In Kizanda Village, Bailey Smith-Helman

Independent Study Project (ISP) Collection

Agriculture is vital to the economic and social systems in Tanzania, composing 30% of the country’s GDP as well as 80% of employment (FAO, 2014). Despite agriculture’s important role, it remains one of the most vulnerable sectors to climate change. Current trends project global average temperature to increase by 0.8-2.6 degrees Celsius, leaving farmers to face changes in rainfall, soil quality, and new pests and diseases (IPCC, 2007). Farmers will be forced to adapt to the changing climate if they are to sustain their livelihoods and the Tanzanian economy. For these reasons, it is important to understand the types of …


Veress M., 2016. Covered Karsts, Reza Khoshraftar Sep 2017

Veress M., 2016. Covered Karsts, Reza Khoshraftar

International Journal of Speleology

No abstract provided.


Biofuels From Crop Residue: Soil Organic Carbon And Climate Impacts In The Us And India, Adam Liska Aug 2017

Biofuels From Crop Residue: Soil Organic Carbon And Climate Impacts In The Us And India, Adam Liska

Adam Liska Papers

The transformation of crop residue to soil organic carbon and CO2 is a conserved process that occurs globally. Due to the mathematics of carbon intensity calculations found in government regulations, the amount of CO2 emitted from crop residue per unit of energy in biofuel is largely independent of the amount of residue removed and the location of its removal, as shown by results from the US and India.

Soil organic carbon (SOC) levels are at equilibria determined by carbon inputs from plant material (+Ic) and loss from oxidation to CO2

Are the US results relevant …


Evaluation Of Simple Geochemical Indicators Of Aeolian Sand Provenance: Late Quaternary Dune Fields Of North America Revisited, Daniel R. Muhs Aug 2017

Evaluation Of Simple Geochemical Indicators Of Aeolian Sand Provenance: Late Quaternary Dune Fields Of North America Revisited, Daniel R. Muhs

United States Geological Survey: Staff Publications

Dune fields of Quaternary age occupy large areas of the world's arid and semiarid regions. Despite this, there has been surprisingly little work done on understanding dune sediment provenance, in part because many techniques are time-consuming, prone to operator error, experimental, highly specialized, expensive, or require sophisticated instrumentation. Provenance of dune sand using K/Rb and K/Ba values in K-feldspar in aeolian sands of the arid and semiarid regions of North America is tested here. Results indicate that K/Rb and K/Ba can distinguish different river sands that are sediment sources for dunes and dune fields themselves have distinctive K/Rb and K/Ba …


Cytonuclear Discordance In The Florida Everglades Invasive Burmese Python (Python Bivittatus) Population Reveals Possible Hybridization With The Indian Python (P. Molurus), Margaret E. Hunter, Nathan A. Johnson, Brian J. Smith, Michelle C. Davis, John S.S. Butterfield, Ray W. Snow, Kristen M. Hart Aug 2017

Cytonuclear Discordance In The Florida Everglades Invasive Burmese Python (Python Bivittatus) Population Reveals Possible Hybridization With The Indian Python (P. Molurus), Margaret E. Hunter, Nathan A. Johnson, Brian J. Smith, Michelle C. Davis, John S.S. Butterfield, Ray W. Snow, Kristen M. Hart

United States Geological Survey: Staff Publications

The invasive Burmese python (Python bivittatus) has been reproducing in the Florida Everglades since the 1980s. These giant constrictor snakes have caused a precipitous decline in small mammal populations in southern Florida following escapes or releases from the commercial pet trade. To better understand the invasion pathway and genetic composition of the population, two mitochondrial (mtDNA) loci across 1,398 base pairs were sequenced on 426 snakes and 22 microsatellites were assessed on 389 snakes. Concatenated mtDNA sequences produced six haplotypes with an average nucleotide and haplotype diversity of π = 0.002 and h = 0.097, respectively. Samples collected …


Moving From Generalisations To Specificity About Mangrove –Saltmarsh Dynamics, Kerrylee Rogers, Ken W. Krauss Jul 2017

Moving From Generalisations To Specificity About Mangrove –Saltmarsh Dynamics, Kerrylee Rogers, Ken W. Krauss

United States Geological Survey: Staff Publications

Spatial and temporal variability in factors influencing mangrove establishment and survival affects the distribution of mangrove, particularly near their latitudinal limit, where mangrove expansion into saltmarsh is conspicuous. In this paper the spatial variability in mangrove distribution and variability in factors influencing mangrove establishment and survival during the Quaternary period are reviewed, focusing on research at latitudinal limits in Australia and mainland USA. Despite similarities in the response of mangrove to some drivers, the expression of these drivers is both spatially and temporally variable, demonstrating the need for analyses of mangrove-saltmarsh dynamics to move beyond generalizations and incorporate regional and …


Observed Changes In Climate And Streamflow In The Upper Rio Grande Basin, Shaleene Chavarria Jul 2017

Observed Changes In Climate And Streamflow In The Upper Rio Grande Basin, Shaleene Chavarria

Earth and Planetary Sciences ETDs

Observed streamflow and climate data are used to test the hypothesis that climate change is already affecting the streamflow volume derived from snow accumulation in ways consistent with climate model-based projections of 21st century streamflow. Annual and monthly changes in streamflow volume and surface climate variables on the upper Rio Grande (URG) near its headwaters in southern Colorado are assessed for water years 1958-2015. Trends in discharge are examined together with variations in snow water equivalent and surface climate variables. Results indicate that temperatures in the basin have increased significantly primarily in the winter and spring seasons, April 1 snow …


A Combined Historical And Sedimentological Reconstruction Of Extratropical Cyclone Derived Coastal Flooding In Boston, Ma, Zachary D. Stromer Jul 2017

A Combined Historical And Sedimentological Reconstruction Of Extratropical Cyclone Derived Coastal Flooding In Boston, Ma, Zachary D. Stromer

Masters Theses

Many flood risk assessments are based on instrumental records less than a century in length. Sedimentary and historical archives provide the opportunity to extend flood records by several centuries to millennia. In doing so these longer flood records provide opportunities for improving upon current flood risk assessment and gaining additional insight on the various climatic and geomorphic processes that drive changes in flood frequency. Such a reconstruction has not been attempted previously for Boston, MA where extratropical cyclones (ETC) are currently the dominant mechanism of coastal flooding. Here, we present both a historical reconstruction of extreme storm tides to affect …


Droughtscape- Summer 2017, National Drought Mitigation Center Jul 2017

Droughtscape- Summer 2017, National Drought Mitigation Center

Droughtscape, Quarterly Newsletter of NDMC, 2007-

CONTENTS

Drought policy write shops conclude in Caribbean...............2

Drought encroaches on Northern Plains in second quarter...........3

Impact tool racks up submissions in second quarter............. 4

Maps on new website highlight drought effects on ag industry.......... 6

Centers release new flash drought tool: QuickDRI........... 6

NDMC contributes to EU report on disaster risk management........... 8

Groups earn Climate Adaptation award for work with tribes............. 9

NDMC, ICPAC director talk collaboration on drought in Greater Horn of Africa......... 11

Up next in MENA: Drought vulnerability assessments........... 12


Rodenticide Incidents Of Exposure And Adverse Effects On Non-Raptor Birds, Nimish B. Vyas Jul 2017

Rodenticide Incidents Of Exposure And Adverse Effects On Non-Raptor Birds, Nimish B. Vyas

United States Geological Survey: Staff Publications

Interest in the adverse effects of rodenticides on birds has focused primarily on raptors. However, non-raptor birds are also poisoned (rodenticide exposure resulting in adverse effects including mortality) by rodenticides through consumption of the rodenticide bait and contaminated prey. A literature search for rodenticide incidents (evidence of exposure to a rodenticide, adverse effects, or exposure to placebo baits) involving non-raptor birds returned 641 records spanning the years 1931 to 2016. The incidents included 17 orders, 58 families, and 190 non-raptor bird species. Nineteen anticoagulant and non-anticoagulant rodenticide active ingredients were associated with the incidents. The number of incidents and species …


Aeromagnetic And Spectral Expressions Of Rare Earth Element Deposits In Gallinas Mountains Area, Central New Mexico, Usa, Mo Li Jul 2017

Aeromagnetic And Spectral Expressions Of Rare Earth Element Deposits In Gallinas Mountains Area, Central New Mexico, Usa, Mo Li

Graduate Theses & Non-Theses

The Gallinas Mountains located in the conjunction of Lincoln County and Torrance County, New Mexico, USA are a series of alkaline volcanic rocks intruded into Permian sedimentary rocks. The Gallinas Mountains area is known to host fluorite and copper as veins containing bastnasite while hydrothermally altered rocks associated with iron oxides have been found in the area as well. In this study, multispectral band ratio method was used for surface mineral interpretation by processing satellite image, while aeromagnetic inversion method was applied using aeromagnetic data, digital elevation model and physical properties for 2-D subsurface structure modeling. Bastnasite has higher magnetic …


A Functional Trait Approach To Examine Plant Community Dynamics In South Florida Hardwood Hammock Forests, Suresh Chandra Subedi Jun 2017

A Functional Trait Approach To Examine Plant Community Dynamics In South Florida Hardwood Hammock Forests, Suresh Chandra Subedi

FIU Electronic Theses and Dissertations

The tropical hardwood forests of south Florida persist as well-drained patches of broadleaf forest separated by brackish water swamp, marsh, or pineland. In this dissertation, a functional trait approach was used to understand the structure and dynamics of these communities and their responses to abiotic and biotic variation. Twenty-seven permanent plots (20 x 20 m2) were established across the south Florida landscape, representing four sub-regions: Everglades marsh, Long Pine Key, Upper Keys, and Lower Keys. Community weighted mean trait values for four of six selected traits showed significant inter-sub-regional variation. Out of them, three traits (specific leaf area, …


Integrating Future Scenario-Based Crop Expansion And Crop Conditions To Map Switchgrass Biofuel Potential In Eastern Nebraska, Usa, Yingxin Gu, Bruce K. Wylie Jun 2017

Integrating Future Scenario-Based Crop Expansion And Crop Conditions To Map Switchgrass Biofuel Potential In Eastern Nebraska, Usa, Yingxin Gu, Bruce K. Wylie

United States Geological Survey: Staff Publications

Switchgrass (Panicum virgatum) has been evaluated as one potential source for cellulosic biofuel feedstocks. Planting switchgrass in marginal croplands and waterway buffers can reduce soil erosion, improve water quality, and improve regional ecosystem services (i.e. it serves as a potential carbon sink). In previous studies, we mapped high risk marginal croplands and highly erodible cropland buffers that are potentially suitable for switchgrass development, which would improve ecosystem services and minimally impact food production. In this study, we advance our previous study results and integrate future crop expansion information to develop a switchgrass biofuel potential ensemble map for current and future …


First Na Lidar Measurements Of Turbulence Heat Flux, Thermal Diffusivity, And Energy Dissipation Rate In The Mesopause Region, Yafang Guo, Alan Z. Liu, Chester S. Gardner Jun 2017

First Na Lidar Measurements Of Turbulence Heat Flux, Thermal Diffusivity, And Energy Dissipation Rate In The Mesopause Region, Yafang Guo, Alan Z. Liu, Chester S. Gardner

Publications

Turbulence is ubiquitous in the mesopause region, where the atmospheric stability is low and wave breaking is frequent. Measuring turbulence is challenging in this region and is traditionally done by rocket soundings and radars. In this work, we show for the first time that the modern Na wind/temperature lidar located at Andes Lidar Observatory in Cerro Pachón, Chile, is able to directly measure the turbulence perturbations in temperature and vertical wind between 85 and 100 km. Using 150 h of lidar observations, we derived the frequency (ω) and vertical wave number (m) spectra for both gravity …