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Articles 271 - 300 of 1044
Full-Text Articles in Earth Sciences
The Influence Of Karst Topography To Ice Cave Occurrence - Example Of Ledena Jama In Lomska Duliba (Croatia), Nenad Buzjak
The Influence Of Karst Topography To Ice Cave Occurrence - Example Of Ledena Jama In Lomska Duliba (Croatia), Nenad Buzjak
The International Workshop on Ice Caves
The research of cave microclimate in general contributes to a better understanding of physical and chemical processes in complex karst geoecosystems. Special challenges for researchers are ice caves. This preliminary report is a part of the project dedicated to the research of deep caves on Velebit Mt. and pointed to the influence of the large karst depression microclimate to cave microclimate, e.g. ice and snow accumulation. The one year study using T/RH data loggers was conducted in Lomska duliba valley (Velebit Mt.) known for frequent temperature inversion and low air temperature, and in partially ice-snow filled Ledena jama (Ice shaft) …
Study Of Multiyear Ice In Medeo Cave (North Ural), Yuri Ivanovich Stepanov, Alexandr Alexandrovich Tainitskiy, Alexandr Valerievich Kichigin, Olga Ivanovna Kadebskaya, Bulat Rafaelevich Mavlyudov
Study Of Multiyear Ice In Medeo Cave (North Ural), Yuri Ivanovich Stepanov, Alexandr Alexandrovich Tainitskiy, Alexandr Valerievich Kichigin, Olga Ivanovna Kadebskaya, Bulat Rafaelevich Mavlyudov
The International Workshop on Ice Caves
The uniqueness of cave ice study lies in characteristic and simulation of continental climate and predictability of its changes. In this study carried out GPR studies in a remote cave Medeo. The cave is located in the territory of Srednevisherski area of West Ural folded zone carbon-bearing karst. The aim of the study was to examine the power and homogeneity of perennial ice formations. According to the results for the first time was defined the power of multi-year ice and built a three-dimensional model of sediment. The cave ice is more enriched with mineral ingredient in comparison with aboveground ice …
Numerical Modeling Of Formation Of A Static Ice Cave – Ningwu Ice Cave, Shanxi, China, Yaolin Shi, Shaohua Yang
Numerical Modeling Of Formation Of A Static Ice Cave – Ningwu Ice Cave, Shanxi, China, Yaolin Shi, Shaohua Yang
The International Workshop on Ice Caves
Ningwu Ice Cave in Shanxi province, China, is the largest Ice cave in China. We use Finite Element Method(FEM) to model the process of heat transfer in the ice cave. We not only calculate thermal conduction in spring, summer and fall, but also calculate the convective heat transfer in winter by introducing an equivalent thermal conductivity of cave air. Our computation shows that the ice cave can be formed within a decade, and reach a stable cyclic state in few centuries. Our calculation also shows that if people set a trap door at the ice cave entrance, especially in winter, …
Detecting Non-Seismic Precursor Earthquake Signals Using Tree Antennas, Jaqueline O. Lopez
Detecting Non-Seismic Precursor Earthquake Signals Using Tree Antennas, Jaqueline O. Lopez
STAR Program Research Presentations
Forecasting earthquakes has yet to be achieved. However, there are numerous non-seismic precursor signals, which become detectable weeks to days before major events – for instance changes in Earth’s electrical surface potential. These changes are due to the arrival of positive electronic charge carriers, known as positive holes, stress-activated deep in the Earth’s crust, in the hypocenter of the future earthquake. Trees can be used as antennas for detecting the surface potential changes due to these mobile charges. This configuration allows for the detection of diurnal variations of the ground potential. Although we only had 105 days worth of data, …
A Comparative Study Of Underwater Robot Path Planning Algorithms For Adaptive Sampling In A Network Of Sensors, Sreeja Banerjee
A Comparative Study Of Underwater Robot Path Planning Algorithms For Adaptive Sampling In A Network Of Sensors, Sreeja Banerjee
School of Computing: Dissertations, Theses, and Student Research
Monitoring lakes, rivers, and oceans is critical to improving our understanding of complex large-scale ecosystems. We introduce a method of underwater monitoring using semi-mobile underwater sensor networks and mobile underwater robots in this thesis. The underwater robots can move freely in all dimension while the sensor nodes are anchored to the bottom of the water column and can move only up and down along the depth of the water column. We develop three different algorithms to optimize the path of the underwater robot and the positions of the sensors to improve the overall quality of sensing of an area of …
Air-Regulated Siphon Spillways: Performance, Modeling, Design, And Construction, Joshua Boatwright
Air-Regulated Siphon Spillways: Performance, Modeling, Design, And Construction, Joshua Boatwright
All Theses
1:Little data exists in the literature for quantification of siphon spillway performance. Proper design of an air regulated siphon spillway requires knowledge of required flow rates and minimum vent size. A set of small siphon spillways were constructed to measure flow rate and required vent size relative to physical characteristics including pipe diameter, length of pipe, and elevation head. Vent sizing was shown to be logarithmically proportional to flow rate. Results were used to develop predictive models for flow rate and vent sizing. Models were validated and refined through testing on a siphon spillway installed on a pond at LaMaster …
An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer
An Examination Of Radionuclide Transport In The Vadose Zone Using Field Lysimeters, Michael Witmer
All Theses
Understanding how radionuclides interact in the subsurface is important for the remediation of contaminated sites, assessment of risk due to radioactive waste disposal, and designing new radioactive waste management strategies. The current understanding of the geochemical behavior of radionuclides in the subsurface and more specifically the vadose zone has been developed through reactive transport modeling supplemented by laboratory experiments. Interactions between radionuclides with the mineral particles and organic matter in the vadose zone can be very complex and while laboratory experiments produce valuable data, few controlled, intermediate scale transport studies have been performed. In order to accurately predict vadose zone …
Michigan's Clay Bluffs: The Description And Comparison Of An Erosion-Dependent Natural Community, Nathaniel G. Fuller
Michigan's Clay Bluffs: The Description And Comparison Of An Erosion-Dependent Natural Community, Nathaniel G. Fuller
Masters Theses
The clay bluffs of Michigan are a natural community found along the shores of the Great Lakes. Groundwater is found to be critical to sustaining the alkaline wetlands on the face of the bluff as well as the source of most erosion events. The clay bluffs are unusual in their vegetation, disturbance regime and geographical context. This thesis focuses primarily on describing seeping clay bluffs and exploring the comparison to other natural communities. The purpose of this is twofold, to better understand the ways in which natural communities are described as distinct from one another, and to assess the distinctness …
Effects Of Road Salt On Asylum Lake Geochemistry, Davina A. Wyman
Effects Of Road Salt On Asylum Lake Geochemistry, Davina A. Wyman
Masters Theses
Several studies indicate that seasonal applications of road deicers can lead to saline runoff entering surface water and groundwater, which can in turn change the chemistry, density, and physical mixing patterns of urban lakes. An investigation at Asylum Lake, an urban lake located near three major roadways, was conducted to determine the degree of road salt contamination in the lake, to determine if salt loading disrupts seasonal mixing patterns, and to determine the extent of redox stratification present due to eutrophic conditions. Samples were collected monthly from the deepest point in Asylum Lake over a 19-month period and analyzed for …
Evaluation Of Earthquake Hazard For Las Vegas Valley, Nevada Incorporating Probabilistic Hazard Assessment And Non--Linear Site Response, Suchan Lamichhane
Evaluation Of Earthquake Hazard For Las Vegas Valley, Nevada Incorporating Probabilistic Hazard Assessment And Non--Linear Site Response, Suchan Lamichhane
UNLV Theses, Dissertations, Professional Papers, and Capstones
Abstract from Manuscript 1, "An alternative analysis of the probabilistic seismic hazard for Las Vegas Valley, Nevada": Probabilistic seismic hazard calculations relevant for rock-site conditions in the Las Vegas Valley, Nevada (LVV) have been computed that account for seismic sources that are not included in the current (2008) USGS national seismic hazard model (NSHM) because of insufficient knowledge or documentation, using the commercial software package EZ-FRISK. The LVV is underlain by a system of mapped, active normal faults that comprise the Las Vegas Valley Fault System (LVVFS), with maximum potential earthquakes to M6.8. The 2008 NSHM explicitly includes only one …
Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer
Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer
Department of Agricultural and Biological Systems Engineering: Dissertations, Theses, and Student Research
Infiltration and runoff are hydrologic processes that effect the amount of water available to plants, for groundwater recharge, and for stream flow. No-till planting (NT) is a management practice used to reduce soil erosion, increase water infiltration, and reduce soil water evaporation, and can have great impact on infiltration and runoff. An investigation was conducted to determine the impact of NT on infiltration and runoff when compared to tilled conditions.
Runoff and precipitation data was gathered from sites at Fillmore County, NE, Phelps County, NE, the USDA-ARS North Appalachian Experimental Watersheds (NAEW) near Coshocton, OH, and the Lennoxville Research Station …
Exposure To Traffic Pollution, Acute Inflammation And Autonomic Response In A Panel Of Car Commuters, Jeremy A. Sarnat, Rachel Golan, Roby Greenwald, Amit U. Raysoni, Priya Kewada, Andrea Winquist, Stefanie E. Sarnat, W. Dana Flanders, Maria C. Mirabelli, Jennifer E. Zora
Exposure To Traffic Pollution, Acute Inflammation And Autonomic Response In A Panel Of Car Commuters, Jeremy A. Sarnat, Rachel Golan, Roby Greenwald, Amit U. Raysoni, Priya Kewada, Andrea Winquist, Stefanie E. Sarnat, W. Dana Flanders, Maria C. Mirabelli, Jennifer E. Zora
School of Earth, Environmental, & Marine Sciences Faculty Publications
Background
Exposure to traffic pollution has been linked to numerous adverse health endpoints. Despite this, limited data examining traffic exposures during realistic commutes and acute response exists. Objectives: We conducted the Atlanta Commuters Exposures (ACE-1) Study, an extensive panel-based exposure and health study, to measure chemically-resolved in-vehicle exposures and corresponding changes in acute oxidative stress, lipid peroxidation, pulmonary and systemic inflammation and autonomic response.
Methods
We recruited 42 adults (21 with and 21 without asthma) to conduct two 2-h scripted highway commutes during morning rush hour in the metropolitan Atlanta area. A suite of in-vehicle particulate components were measured in …
Mantle Transition Zone Discontinuities Beneath The Contiguous United States, Stephen S. Gao, Kelly H. Liu
Mantle Transition Zone Discontinuities Beneath The Contiguous United States, Stephen S. Gao, Kelly H. Liu
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
Using over 310,000 high-quality radial receiver functions recorded by the USArray and other seismic stations in the contiguous United States, the depths of the 410 km and 660 km discontinuities (d410 and d660) are mapped in over 1,000 consecutive overlapping circles with a radius of 1⁰. The average mantle transition zone (MTZ) thickness for both the western and central/eastern U.S. is within 3 km from the global average of 250 km, suggesting an overall normal MTZ temperature beneath both areas. The Pacific Coast Ranges and the southern Basin and Range Province are underlain by a depressed d410, indicating higher-than-normal temperature …
Build-And-Fill Development Of Lower Ismay (Middle Pennsylvanian Paradox Formation) Phylloid-Algal Mounds Of The Paradox Basin, Southeastern Utah, Lincoln H. Reed
Build-And-Fill Development Of Lower Ismay (Middle Pennsylvanian Paradox Formation) Phylloid-Algal Mounds Of The Paradox Basin, Southeastern Utah, Lincoln H. Reed
Theses and Dissertations
Phylloid-algal mounds form heterogeneous hydrocarbon reservoirs in the southeastern portion (Blanding sub-basin) of the Paradox Basin. Well-studied Lower Ismay mounds exposed along walls of the San Juan River gorge in the vicinity of Eight Foot Rapids, the west limb of the Raplee Anticline, and at the classic Honaker Trail locality (southwestern Paradox Basin) have often been cited as outcrop analogs of productive subsurface mounds. Until now, however, there has not been a complete description of the distribution, size, and spacing of outcropping algal mounds at the classic Eight Foot Rapids locality. The Lower Ismay sequence was analyzed in the context …
Tempo And Mode Of Domestication During The Neolithic Revolution: Evidence From Dental Mesowear And Microwear Of Sheep, Melissa Zolnierz
Tempo And Mode Of Domestication During The Neolithic Revolution: Evidence From Dental Mesowear And Microwear Of Sheep, Melissa Zolnierz
Graduate Theses and Dissertations
The Neolithic Revolution marked a dramatic change in human subsistence practices. In order to explain this change, we must understand the motive forces behind it. Researchers have proposed many different stimuli, with most theories invoking environmental dynamics, human population density increases beyond environmental carrying capacity, and the natural outgrowth of human and plant/animal interactions. However, unanswered questions remain concerning the mechanics of animal domestication. Traditional studies of changing faunal morphology and skeletal population profiles offer some clues, but such research has had limited success identifying stages intermediate between wild and domesticated forms, which makes it difficult to discern initial attempts …
One-Dimensional Weakly Nonlinear Model Equations For Rossby Waves, David Henry, Rossen Ivanov
One-Dimensional Weakly Nonlinear Model Equations For Rossby Waves, David Henry, Rossen Ivanov
Articles
In this study we explore several possibilities for modelling weakly nonlinear Rossby waves in fluid of constant depth, which propagate predominantly in one direction. The model equations obtained include the BBM equation, as well as the integrable KdV and Degasperis-Procesi equations.
Seismic Imaging Of Mantle Transition Zone Discontinuities Beneath The Northern Red Sea And Adjacent Areas, A. A. Mohamed, Stephen S. Gao, A. A. Elsheikh, Kelly H. Liu, Youqiang Yu, R. E. Fat-Helbary
Seismic Imaging Of Mantle Transition Zone Discontinuities Beneath The Northern Red Sea And Adjacent Areas, A. A. Mohamed, Stephen S. Gao, A. A. Elsheikh, Kelly H. Liu, Youqiang Yu, R. E. Fat-Helbary
Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works
The dramatic asymmetry in terms of surface elevation, Cenozoic volcanisms and earthquake activity across the Red Sea is an enigmatic issue in global tectonics, partially due to the unavailability of broad-band seismic data on the African Plate adjacent to the Red Sea. Here, we report the first comprehensive image of the mantle transition zone (MTZ) discontinuities using data from the Egyptian National Seismic Network, and compare the resulting depths of the 410 and 660-km discontinuities with those observed on the Arabian side. Our results show that when a standard earth model is used for time-to-depth conversion, the resulting depth of …
Kinematics And Timing Of Superposed Deformation In The Funeral Mountains Metamorphic Core Complex, Death Valley, Ca, Katrina Marie Sauer
Kinematics And Timing Of Superposed Deformation In The Funeral Mountains Metamorphic Core Complex, Death Valley, Ca, Katrina Marie Sauer
UNLV Theses, Dissertations, Professional Papers, and Capstones
The Funeral Mountains metamorphic core complex (FMMCC) in Death Valley, California exposes middle to lower crustal rocks of the Sevier-Laramide orogen in the footwall of the Miocene Boundary Canyon detachment. The structurally deepest rocks in the FMMCC are exposed in Monarch Canyon, where the Meso- to Neoproterozoic metasedimentary rocks record upper amphibolite facies metamorphism with migmatites developed at the deepest levels. Distributed ductile deformation and stratigraphically-localized high-strain zones, termed intracore shear zones, are responsible for attenuation and local stratigraphic omission during top-northwest non-coaxial deformation. The structurally deepest Monarch Spring shear zone (MSSZ) juxtaposes the migmatitic paragneisses below against greenschist to …
Characterization Of Rain And Stormwater Nitrogen Inputs To The Mississippi Sound: A Landscape Approach, Joshua Michael Allen
Characterization Of Rain And Stormwater Nitrogen Inputs To The Mississippi Sound: A Landscape Approach, Joshua Michael Allen
Master's Theses
Urbanization in coastal watersheds is becoming an increasingly important issue in the world. Increased impervious surface cover, a factor of urbanization, has drawn more attention to stormwater runoff as a source of contamination to receiving waters. In this study, nitrogen species from rain and stormwater were analyzed across three different landscape types along the Mississippi Sound (hardened, residential, and pristine), as well as from drainage pipes that flow directly into to the Mississippi Sound. Nitrogen stable isotopes were used to trace the stormwater nitrogen to the surface waters and biota within the Sound.
The objective of this study was to …
Vadose Zone Lag Time And Potential 21st Century Climate Change Effects On Spatially Distributed Groundwater Recharge In The Semi-Arid Nebraska Sand Hills, N. R. Rossman, Vitaly A. Zlotnik, Clinton Rowe, Jozsef Szilagyi
Vadose Zone Lag Time And Potential 21st Century Climate Change Effects On Spatially Distributed Groundwater Recharge In The Semi-Arid Nebraska Sand Hills, N. R. Rossman, Vitaly A. Zlotnik, Clinton Rowe, Jozsef Szilagyi
Department of Earth and Atmospheric Sciences: Faculty Publications
Deep drainage of water below plant root zones (potential groundwater recharge) will become groundwater recharge (GR) after a delay (or lag time) in which soil moisture traverses the vadose zone before reaching the water table. Depending on the thickness of the vadose zone, the magnitude of deep drainage, and soil hydraulic properties, lag times will vary broadly, exceeding decades to centuries in semi-arid and arid environments. Yet, studies of future climate change impacts to GR have typically avoided focusing on impacts beyond 100 years and often neglect to consider lag effects caused by the vadose zone. We investigate the effects …
Mars-Relevant Phosphate Minerals And Implications For Martian Habitability, Christopher Adcock
Mars-Relevant Phosphate Minerals And Implications For Martian Habitability, Christopher Adcock
UNLV Theses, Dissertations, Professional Papers, and Capstones
This dissertation is comprised of three studies focused on martian phosphate availability, with an introductory chapter introducing and linking the three studies. Chapter two is on the subject of merrillite synthesis. Merrillite is an extraterrestrial Ca-phosphate mineral similar to the mineral whitlockite and is found as a dominant primary phosphate mineral in martian meteorites. The chapter includes methods of whitlockite and merrillite synthesis as well as a detailed characterization of the produced minerals and a mechanism by which charge balance can be maintained when merrillite is synthesized through dehydrogenation of whitlockite.
Chapter three presents the results of kinetic and thermodynamic …
Porphyry Copper Exploration Of The Hualapai Mountains, Mohave County, Arizona, Usa: A Multi-Faceted Approach, Patrick Kevin Meazell
Porphyry Copper Exploration Of The Hualapai Mountains, Mohave County, Arizona, Usa: A Multi-Faceted Approach, Patrick Kevin Meazell
UNLV Theses, Dissertations, Professional Papers, and Capstones
A variety of exploration methods including geologic mapping, trace- and major-level geochemical analyses, fluid inclusion petrography, remote sensing, and SWIR clay spectroscopy were used to investigate the potential for porphyry Cu-Mo mineralization at the Wikieup prospect, in the southern Hualapai Mountains of northwestern Arizona. Aspects of the Mineral Park mine were used as an analogue to guide exploration due to the proximity and similar geology of the area.
The Hualapai Mountains are a series of northwest-trending Precambrian gneisses, schists, granitoids and amphibolites that have been cut by younger intrusive rocks. Within the Wikieup study area, the intrusive rocks include aplite …
The Significance Of Dolomitized Hunton Strata In The Kinta And Bonanza Fields Of The Arkoma Basin, Christopher William Trotter
The Significance Of Dolomitized Hunton Strata In The Kinta And Bonanza Fields Of The Arkoma Basin, Christopher William Trotter
Graduate Theses and Dissertations
The Hunton Group has been a prolific hydrocarbon-producing reservoir across much of Oklahoma and western Arkansas. The group is a Silurian-Devonian aged interval that is comprised of sequences of limestone, dolomite, and calcareous shale. The group is divided into several formations. The subdivisions include the Chimneyhill Subgroup, Henryhouse, Haragan and Bois d'Arc Formations. Reservoir quality in the Hunton Group is significantly dependent upon the diagenetic events and depositional environments of the sediments. Most hydrocarbon production, from within the Hunton Group, comes from members that have undergone dolomite replacement of the parent limestone.
The higher amounts of porosity and permeability are …
Comparisons Of Hydrogeologic Modeling Methods To Define Capture Zones For Public Water Supply Wells In Northern Arkansas, Paula Anderson
Comparisons Of Hydrogeologic Modeling Methods To Define Capture Zones For Public Water Supply Wells In Northern Arkansas, Paula Anderson
Graduate Theses and Dissertations
The usefulness, applicability, and practicality of more complex and resource consuming methods for groundwater modeling has been in question since computer based groundwater modeling was established (Anderson, 1992). In many situations, computer modeling of groundwater flow is a necessity and useful for extrapolating data where none exists or it is impossible or impractical to acquire. However, when delineating a recharge area around a public water well for protection purposes, it is unknown if more detailed computer modeling results are better than simpler hydrologic calculations and site study. In the case of public drinking water supply wells located in various aquifers …
U.S. Drought Monitor, July 29, 2014, Brad Rippey
U.S. Drought Monitor, July 29, 2014, Brad Rippey
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for July 29, 2014 (7/29/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.
Repeated Multibeam Echosounder Hydrographic Surveys Of 15 Selected Bridge Crossings Along The Missouri River From Niobrara To Rulo, Nebraska, During The Flood Of 2011, Benjamin J. Dietsch, Brenda K. Densmore, Kellan R. Strauch
Repeated Multibeam Echosounder Hydrographic Surveys Of 15 Selected Bridge Crossings Along The Missouri River From Niobrara To Rulo, Nebraska, During The Flood Of 2011, Benjamin J. Dietsch, Brenda K. Densmore, Kellan R. Strauch
United States Geological Survey: Water Reports and Publications
In 2011, unprecedented flooding in the Missouri River prompted transportation agencies to increase the frequency of monitoring riverbed elevations near bridges that cross the Missouri River. Hydrographic surveys were completed in cooperation with the Nebraska Department of Roads, using a multibeam echosounder at 15 highway bridges spanning the Missouri River from Niobrara to Rulo, Nebraska during and after the extreme 2011 flood.
Evidence of bed elevation change near bridge piers was documented. The greatest amount of bed elevation change during the 2011 flood documented for this study occurred at the Burt County Missouri River Bridge at Decatur, Nebraska, where scour …
Hf-Nd Isotopic Variability In Mineral Dust From Chinese And Mongolian Deserts: Implications For Sources And Dispersal, Wancang Zhao, Youbin Sun, William Balsam, Huayu Lu
Hf-Nd Isotopic Variability In Mineral Dust From Chinese And Mongolian Deserts: Implications For Sources And Dispersal, Wancang Zhao, Youbin Sun, William Balsam, Huayu Lu
Dartmouth Scholarship
Mineral dust provenances are closely related to the orogenic processes which may have distinct Hf-Nd isotopic signatures. Here we report the clay-sized (<2 μm) Hf-Nd isotope data from Asian dust sources to better constrain the source and transport dynamics of dust deposition in the North Pacific. Our results show that there is a more positive radiogenic Hf isotopic composition with clay-sized fractions than the corresponding bulk sample and a decoupling of the Hf-Nd couplets in the clay formation during the weathering process. The clay-sized Hf-Nd isotopic compositions of the desert samples from the Sino-Korean-Tarim Craton (SKTC) are different from those of the Gobi and deserts from the Central Asian Orogeny Belt (CAOB) due to varying tectonic and weathering controls. The Hf-Nd isotopic compositions of dust in the North Pacific central province (NPC) match closely with those from the Taklimakan, Badain Jaran and adjacent Tengger deserts, implying that the NPC dust was mainly transported from these potential sources by the westerly jet. Our study indicates that dusts from the CAOB Gobi deserts either didn't arrive in NPC or were quantitatively insignificant, but they were likely transported to the North Pacific margin province (NPM) by East Asian winter monsoon.
Integrating Land Cover Modeling And Adaptive Management To Conserve Endangered Species And Reduce Catastrophic Fire Risk, David Breininger, Brean Duncan, Mitchell Eaton, Fred Johnson, James Nichols
Integrating Land Cover Modeling And Adaptive Management To Conserve Endangered Species And Reduce Catastrophic Fire Risk, David Breininger, Brean Duncan, Mitchell Eaton, Fred Johnson, James Nichols
United States Geological Survey: Staff Publications
Land cover modeling is used to inform land management, but most often via a two-step process, where science informs how management alternatives can influence resources, and then, decision makers can use this information to make decisions. A more efficient process is to directly integrate science and decision-making, where science allows us to learn in order to better accomplish management objectives and is developed to address specific decisions. Co-development of management and science is especially productive when decisions are complicated by multiple objectives and impeded by uncertainty. Multiple objectives can be met by the specification of trade offs, and relevant uncertainty …
Integrating Microbial Physiology And Physio-Chemical Principles In Soils With The Microbial-Mineral Carbon Stabilization (Mimics) Model, William R. Wieder, A. Stuart Grandy, Cynthia M. Kallenbach, Gordon B. Bonan
Integrating Microbial Physiology And Physio-Chemical Principles In Soils With The Microbial-Mineral Carbon Stabilization (Mimics) Model, William R. Wieder, A. Stuart Grandy, Cynthia M. Kallenbach, Gordon B. Bonan
Faculty Publications
A growing body of literature documents the pressing need to develop soil biogeochemistry models that more accurately reflect contemporary understanding of soil processes and better capture soil carbon (C) responses to environmental perturbations. Models that explicitly represent microbial activity offer inroads to improve representations of soil biogeochemical processes, but have yet to consider relationships between litter quality, functional differences in microbial physiology, and the physical protection of microbial byproducts in forming stable soil organic matter (SOM). To address these limitations, we introduce the MIcrobial-MIneral Carbon Stabilization (MIMICS) model, and evaluate it by comparing site-level soil C projections with observations from …
U.S. Drought Monitor, July 22, 2014, David Miskus
U.S. Drought Monitor, July 22, 2014, David Miskus
United States Agricultural Commodities in Drought Archive
Drought map of U.S. for July 22, 2014 (7/22/14) plus: U.S. crop areas experiencing drought (map), Approximate percentage of crop located in drought, by state (bar graph), Percent of crop area located in drought, past 52 weeks (line graph) for: Corn, Soybeans, Hay, Cattle, Winter wheat.