Physical Sciences and Mathematics Commons^™

Regenerating Agricultural Landscapes With Perennial Groundcover For Intensive Crop Production, Kenneth J. Moore, Robert P. Anex, Amani E. Elobeid, Shuizhang Fei, Cornelia B. Flora, A. Susana Goggi, Keri L. Jacobs, Prashant Jha, Amy L. Kaleita, Douglas L. Karlen, David A. Laird, Andrew W. Lenssen, Thomas Lubberstedt, Marshall D. Mcdaniel, D. Raj Raman, Sharon L. Weyers

Douglas L Karlen

The Midwestern U.S. landscape is one of the most highly altered and intensively managed ecosystems in the country. The predominant crops grown are maize (Zea mays L.) and soybean [Glycine max (L.) Merr]. They are typically grown as monocrops in a simple yearly rotation or with multiple years of maize (2 to 3) followed by a single year of soybean. This system is highly productive because the crops and management systems have been well adapted to the regional growing conditions through substantial public and private investment. Furthermore, markets and supporting infrastructure are highly developed for both crops. As maize and …

Extensive Tissue-Specific Transcriptomic Plasticity In Maize Primary Roots Upon Water Deficit, Nina Opitz, Caroline Marcon, Anja Paschold, Waqas Ahmed Malik, Andrew Lithio, Ronny Brandt, Hans-Peter Piepho, Dan Nettleton, Frank Hochholdinger

Dan Nettleton

Water deficit is the most important environmental constraint severely limiting global crop growth and productivity. This study investigated early transcriptome changes in maize (Zea mays L.) primary root tissues in response to moderate water deficit conditions by RNA-Sequencing. Differential gene expression analyses revealed a high degree of plasticity of the water deficit response. The activity status of genes (active/inactive) was determined by a Bayesian hierarchical model. In total, 70% of expressed genes were constitutively active in all tissues. In contrast, <3% (50 genes) of water deficit-responsive genes (1915) were consistently regulated in all tissues, while >75% (1501 genes) were specifically regulated in a single root tissue. Water deficit-responsive genes were most numerous in the …

Modeling Spatial And Temporal Variation In Natural Background Specific Conductivity, John Olson, Susan M. Cormier

John Olson

Effectiveness Of Four Water-Bearing Zones Of The Glacierized Basin In Meltwater Runoff Modeling, Umesh K. Haritashya

Umesh K. Haritashya

Meltwater runoff modeling from glacierized basins needs several input data, including total meltwater contributing area. This study utilizes optical remote sensing data to assess glacierized basins in the central Himalayas where snow and glaciers contribute substantially to the water resources. Result shows that there are four main water-bearing zones in the basin: (a) dry snow, (b) wet snow, (c) exposed glacial ice, and (d) debris-covered glacial ice, and it is possible to differentiate and map these zones and their spatio-temporal variations from satellite sensor data. These zones can then be incorporated in meltwater runoff modeling as separate entities because they …

Predicting Combined Effects Of Land Use And Climate Change On River And Stream Salinity, John Olson

John Olson

Input Uncertainty On Watershed Modeling: Evaluation Of Precipitation And Air Temperature Data By Latent Variables Using Swat, Ruoyu Wang

Ruoyu Wang

Tiered Approaches In Analyzing Rice Field Pesticide Fate And Transport For Ecological Risk Assessment, Ruoyu Wang

Ruoyu Wang

No abstract provided.

The Soil Moisture Velocity Equation, Fred L. Ogden, Craig C. Douglas

Fred L. Ogden

Assessment Of Optional Sediment Transport Functions Via The Complex Watershed Simulation Model Swat, Ruoyu Wang

Ruoyu Wang

Combined And Synergistic Effects Of Climate Change And Urbanization On Water Quality In The Wolf Bay Watershed, Southern Alabama, Ruoyu Wang

Ruoyu Wang

Biophysical And Hydrological Effects Of Future Climate Change Including Trends In Co2, In The St. Joseph River Watershed, Eastern Corn Belt, Ruoyu Wang

Ruoyu Wang

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Water, Growth And The Endangered Species Act, Holly Doremus

Holly Doremus

24 pages.

Exchange Flows In An Urban Water Body: Bayou St. John Responses To The Removal Of Flood Control Structures, Future Water Elevation Control, And Water Quality, Robin L. Schroeder

Robin S. Schroeder MD

Bayou St. John, an urban water body extending south from Lake Pontchartrain, has two anthropogenic structures that regulate flow from the Lake . The City of New Orleans has plans to remove the inner control structure to improve water quality. Field and numerical methods used in this study show removing this structure increased water elevations throughout the Bayou but resulted in lower water elevation signal amplitudes that caused a lower tidal flow exchange from north to south. Bulk Richardson numbers showed mixing was inversely related to flow and the Bayou generally remains stratified. Resuspension of contaminated sediment could negatively impact …

Three-Dimensional Geologic Modeling And Groundwater Flow Modeling Above A Co2 Sequestration Test Site, Eric Wade Peterson, David H. Malone

Eric Wade Peterson

Three-Dimensional Geological Model Of Quaternary Sediments In Walworth County, Wisconsin, Usa, Jodi Jau, Jason F. Thomason, David H. Malone, Eric Wade Peterson

Eric Wade Peterson

Modeling The Sediment Fill Of The Uppertroy Pre-Glacial Bedrock Valley,Mchenry County, Llinois, Usa, Jodi Lau, Jason F. Thomason, David H. Malone, Eric Wade Peterson

Eric Wade Peterson

Effects Of Changes In Moisture Source And The Upstream Rainout On Stable Isotopes In Precipitation – A Case Study In Nanjing, Eastern China, Y. Tang, H. Pang, W. Zhang, Y. Li, Shuang-Ye Wu, S. Hou

Shuang-ye Wu

In the Asian monsoon region, variations in the stable isotopic composition of speleothems have often been attributed to the "amount effect". However, an increasing number of studies suggest that the "amount effect" in local precipitation is insignificant or even non-existent. To explore this issue further, we examined the variability of daily stable isotopic composition (δ18O) in precipitation from September 2011 to November 2014 in Nanjing, eastern China. We found that intra-seasonal variations of δ18O during summer were not significantly correlated with local rainfall amount but could be linked to changes in the moisture source location and rainout processes in the …

Paleogeographic, Paleoceanographic, And Tectonic Controls On Early Late Ordovician Graptolite Diversity Patterns, Daniel Goldman, Shuang-Ye Wu

Shuang-ye Wu

The Katian Age (early Late Ordovician) was a time of significant decline in marine biodiversity, but whether this decline was a real phenomenon or an artifact of the relatively few studies devoted to this interval requires further research. We examined the pattern of graptolite faunal changes across the boundary between the Climacograptus bicornis and Diplacanthograptus caudatus graptolite zones in North America and on several other continents.

A sharp decline in species diversity occurs in the Appalachian Basin. Scores for normalized diversity dropped from 20 in the C. bicornis Zone to 7 in the D. caudatus Zone. Only 11% of the …

Reconstruction Of The Hirnantian (Late Ordovician) Palaeotopography In The Upper Yangtze Region, Linna Zhang, Junxuan Fan, Qing Chen, Shuang-Ye Wu

Shuang-ye Wu

Reconstruction of the Hirnantian (Late Ordovician) palaeotopography in South China is important for understanding the distribution pattern of the Hirnantian marine depositional environment. In this study, we reconstructed the Hirnantian palaeotopography in the Upper Yangtze region based on the rankings of the palaeo-water depths, which were inferred according to the lithofacies and biofacies characteristics of the sections. Data from 374 Hirnantian sections were collected and standardized through the online Geobiodiversity Database. The Ordinary Kriging interpolation method in the ArcGIS software was applied to create the continuous surface of the palaeo-water depths, i.e. the Hirnantian palaeotopography. Meanwhile, the line transect analysis …

Transition From Contraction To Extension In The Northeastern Basin And Range: New Evidence From The Copper Mountains, Nevada, Jeffrey M. Rahl, Allen J. Mcgrew, Kenneth A. Foland

Allen J. McGrew

New mapping, structural analysis, and 40Ar/39Ar dating reveal an unusually well‐constrained history of Late Eocene extension in the Copper Mountains of the northern Basin and Range province. In this area, the northeast‐trending Copper Creek normal fault juxtaposes a distinctive sequence of metacarbonate and granitoid rocks against a footwall of Upper Precambrian to Lower Cambrian quartzite and phyllite. Correlation of the hanging wall with footwall rocks to the northwest provides an approximate piercing point that requires 8–12 km displacement in an ESE direction. This displaced fault slice is itself bounded above by another normal fault (the Meadow Fork Fault), which brings …

Paleogeographic, Paleoceanographic, And Tectonic Controls On Early Late Ordovician Graptolite Diversity Patterns, Daniel Goldman, Shuang-Ye Wu

Daniel Goldman

The Katian Age (early Late Ordovician) was a time of significant decline in marine biodiversity, but whether this decline was a real phenomenon or an artifact of the relatively few studies devoted to this interval requires further research. We examined the pattern of graptolite faunal changes across the boundary between the Climacograptus bicornis and Diplacanthograptus caudatus graptolite zones in North America and on several other continents.

A sharp decline in species diversity occurs in the Appalachian Basin. Scores for normalized diversity dropped from 20 in the C. bicornis Zone to 7 in the D. caudatus Zone. Only 11% of the …

Prevailing Weather Conditions During Summer Seasons Around Gangotri Glacier, Pratap Singh, Umesh K. Haritashya, K. S. Ramasastri, Naresh Kumar

Umesh K. Haritashya

Meteorological data collected near the snout of the Gangotri Glacier suggest that the study area receives less rainfall. The average seasonal rainfall is observed to be about 260 mm. The rainfall distribution does not show any monsoon impact. Amount of seasonal rainfall is highly variable (131.4-368.8 mm) from year to year, but, in general, August had the maximum rainfall. A verage daily maximum and minimum temperatures were 14.7 and 4.1°C respectively, whereas average mean temperature was 9.4°C. July was recorded as the warmest month. During daytime, wind speed was four times higher than that at night-time. The average daytime and …

Multispectral Image Analysis Of Glaciers And Glacier Lakes In The Chugach Mountains, Alaska, Jeffrey Kargel, Matthew Beedle, Andrew Bush, Francisco Carreño, Elena Castellanos, Umesh Haritashya, Gregory Leonard, Javier Lillo, Ivan Lopez, Mark Pleasants, Edward Pollock, David Wolfe

Umesh Haritashya

The Chugach Mountains contain the largest nonpolar alpine glaciers in the world and include a wide variety of glacier types: some are land terminating; some calve variously into tidewater, lakes, and rivers; some are heavily debris covered; some are surge-type, whereas others are neither debris covered nor surge type. Nearly all are retreating, thinning, or both, though some rare ones are advancing, and some are thickening at high elevations. To assist the further documentation of changes, we establish an inventory of glaciers in the eastern Chugach Mountains. Several case studies of diverse glacier types showcase remotesensing applications and are used …

Encyclopedia Of Snow, Ice And Glaciers, Vijay P. Singh, Pratap Singh, Umesh K. Haritashya

Umesh K. Haritashya

The objective of this encyclopedia is to present the current state of scientific understanding of various aspects of earth’s cryosphere – snow, glaciers, ice caps, ice sheets, ice shelves, sea ice, river and lake ice, and permafrost – and their related interdisciplinary connections under one umbrella. Therefore, every effort has been made to provide a comprehensive coverage of cryosphere by including a broad array of topics, such as the atmospheric processes responsible for snow formation; snowfall observations; snow cover and snow surveys; transformation of snow to ice and changes in their properties; classification of ice and glaciers and their worldwide …

Porosity Controls On Secondary Recovery At The Loudon Field, South-Central Illinois, John S. Wagle, David H. Malone, Eric Wade Peterson

Eric Wade Peterson

Role Of Multiple High-Capacity Irrigation Wells On A Surficial Sand And Gravel Aquifer, Logan Seipel, Eric Wade Peterson, David H. Malone, Jason F. Thomason

Eric Wade Peterson

Evaluation Of Tillage And Crop Rotation Effects On Groundwater Quality—Nashua Project, Rameshwar S. Kanwar, Douglas Karlen, Thomas S. Colvin, William W. Simpkins, Vince J. Mcfadden

Douglas L Karlen

Sampling shows that agricultural chemicals are occurring increasingly in ground- and surface water in Iowa. The same trend has been reported throughout the United States; one study reported finding 73 pesticides in the groundwater of 34 states. Even pesticides known to be adsorbed to soil particles (and thus relatively immobile) have been found in a few sampled wells in trace concentrations. Nitrate-nitrogen (NO3-N) is the most common agricultural chemical found in groundwater. Nitrogen fertilizers and pesticides applied to the soil surface prior to and immediately following crop planting are particularly susceptible to surface runoff or leaching to groundwater through the …

Estimation Of The Effects Of Climate Variability On Crop Yield In The Midwest Usa, Ruoyu Wang

Ruoyu Wang