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A. Overview Of The Flathead Lake Seismic Survey, Robert W. Lankston 2017 University of Montana - Missoula

A. Overview Of The Flathead Lake Seismic Survey, Robert W. Lankston

1970 Flathead Lake Seismic Survey

This book contains a summary of the key phases of acquisition and use of the reflection seismic data that were collected in 1970 in Flathead Lake and the evolution of the physical and digital archives of that seismic project.


Young Earth Flood Geology In The Grand Canyon, John H. Whitmore 2017 Cedarville University

Young Earth Flood Geology In The Grand Canyon, John H. Whitmore

John H. Whitmore, Ph.D.

No abstract provided.


Impacts Of Climate Change On Hydrology, Water Quality And Crop Productivity In The Ohio-Tennessee River Basin, Yiannis Panagopoulos, Philip W. Gassman, Raymond W. Arritt, Daryl E. Herzmann, Todd D. Campbell, Adriana Valcu, Manoj K. Jha, Catherine L. Kling, Raghavan Srinivasan, Michael White, Jeffrey G. Arnold 2017 Iowa State University

Impacts Of Climate Change On Hydrology, Water Quality And Crop Productivity In The Ohio-Tennessee River Basin, Yiannis Panagopoulos, Philip W. Gassman, Raymond W. Arritt, Daryl E. Herzmann, Todd D. Campbell, Adriana Valcu, Manoj K. Jha, Catherine L. Kling, Raghavan Srinivasan, Michael White, Jeffrey G. Arnold

Catherine Kling

Nonpoint source pollution from agriculture is the main source of nitrogen and phosphorus in the stream systems of the Corn Belt region in the Midwestern US. The eastern part of this region is comprised of the Ohio-Tennessee River Basin (OTRB), which is considered a key contributing area for water pollution and the Northern Gulf of Mexico hypoxic zone. A point of crucial importance in this basin is therefore how intensive corn-based cropping systems for food and fuel production can be sustainable and coexist with a healthy water environment, not only under existing climate but also under climate change conditions in ...


A Tale Of Three Watersheds: Nonpoint Source Pollution And Conservation Practices Across Iowa, Keith E. Schilling, Mark D. Tomer, Philip W. Gassman, Catherine Kling, Thomas M. Isenhart, Thomas B. Moorman, William W. Simpkins, Calvin F. Wolter 2017 Iowa Geological Survey

A Tale Of Three Watersheds: Nonpoint Source Pollution And Conservation Practices Across Iowa, Keith E. Schilling, Mark D. Tomer, Philip W. Gassman, Catherine Kling, Thomas M. Isenhart, Thomas B. Moorman, William W. Simpkins, Calvin F. Wolter

Catherine Kling

Many conservation practices and implementation programs exist to address nonpoint source (NPS) pollution losses from agricultural landscapes (Helmers et al., this issue). In order to select the most appropriate practices and programs for reducing NPS pollution in a specific region while maintaining economic return for the landowner, the interacting processes of agricultural management and watershed hydrology need to be understood across broad spatial scales. On a nationwide basis, it is easy to see how NPS pollution in one part of the country might be different than those in another region of the country. For example, cotton growers in the South ...


Global Solutions To Regional Problems: Collecting Global Expertise To Address The Problem Of Harmful Cyanobacterial Blooms. A Lake Erie Case Study, George S. Bullerjahn, Robert M. McKay, Timothy W. Davis, David B. Baker, Gregory L. Boyer, Leslie V. D'Anglada, Gregory J. Doucette, Jeff C. Ho, Elena G. Irwin, Catherine L. Kling, Raphael M. Kudela, Rainer Kurmayer, Anna M. Michalak, Joseph D. Ortiz, Timothy G. Otten, Hans W. Paerl, Boqiang Qin, Brent L. Sohngen, Richard P. Stumpf, Petra M. Visser, Steven W. Wilhelm 2017 Bowling Green State University

Global Solutions To Regional Problems: Collecting Global Expertise To Address The Problem Of Harmful Cyanobacterial Blooms. A Lake Erie Case Study, George S. Bullerjahn, Robert M. Mckay, Timothy W. Davis, David B. Baker, Gregory L. Boyer, Leslie V. D'Anglada, Gregory J. Doucette, Jeff C. Ho, Elena G. Irwin, Catherine L. Kling, Raphael M. Kudela, Rainer Kurmayer, Anna M. Michalak, Joseph D. Ortiz, Timothy G. Otten, Hans W. Paerl, Boqiang Qin, Brent L. Sohngen, Richard P. Stumpf, Petra M. Visser, Steven W. Wilhelm

Catherine Kling

In early August 2014, the municipality of Toledo, OH (USA) issued a ‘do not drink’ advisory on their water supply directly affecting over 400,000 residential customers and hundreds of businesses (Wilson, 2014). This order was attributable to levels of microcystin, a potent liver toxin, which rose to 2.5 mg L1 in finished drinking water. The Toledo crisis afforded an opportunity to bring together scientists from around the world to share ideas regarding factors that contribute to bloom formation and toxigenicity, bloom and toxin detection as well as prevention and remediation of bloom events. These discussions took place at ...


Nitrification In Acid Soils, R. E. Stepheson 2017 Iowa State College

Nitrification In Acid Soils, R. E. Stepheson

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

It is quite generally believed now that nitrification may occur in acid soils, at least to some extent. The addition of lime, however, results in practically all cases in an increased activity of the nitrifying flora. This is especially true when soils are strongly acid in reaction and low in organic matter and when ammonium sulfate is used to measure nitrification.

Probably it is not merely because lime neutralizes acid soil conditions that it increases nitrification. There may be very important indirect effects of liming which are responsible for greater nitrifying action. Lime makes the soil conditions more favorable for ...


Effect Of Seasonal Conditions And Soil Treatment On Bacteria And Molds In Soil, P. E. Brown, W. V. Halversen 2017 Iowa State College

Effect Of Seasonal Conditions And Soil Treatment On Bacteria And Molds In Soil, P. E. Brown, W. V. Halversen

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The study of the microorganic population of the soil has revealed many interesting facts but none more significant nor of more far-reaching importance than the discovery that molds occur in soils and perform various functions which directly or indirectly exert considerable influence on soil fertility.

The occurrence and activities of bacteria in the soil has been the subject of extensive inquiry and much knowledge along this line has been accumulated. These organisms have been found to occur in large numbers in practically all soils and to play a prominent part in the reactions which must necessarily take place in soils ...


Effects Of Certain Alkali Salts On Ammonification, P. E. Brown, D. R. Johnson 2017 Iowa State College

Effects Of Certain Alkali Salts On Ammonification, P. E. Brown, D. R. Johnson

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The occurrence of so-called" alkali spots" in certain Iowa soils has been nnted in recent publications, these spots are found only in the Wisconsin drift soil area, in association with peat deposits, and are the result of course of peculiarly poor drainage conditions. It is unnecessary here to consider further the causes of these formations or the methods which should be followed in reclaiming the areas affected as these points have been discussed in the publications referred to. It will be sufficient to call attention to the results of the chemical studies of the spots and to consider briefly some ...


Phosphorus, Potassium And Ph Management Issues Following Drought-Damaged Crops, Antonio P. Mallarino, John E. Sawyer 2017 Iowa State University

Phosphorus, Potassium And Ph Management Issues Following Drought-Damaged Crops, Antonio P. Mallarino, John E. Sawyer

John E. Sawyer

Exceptionally dry conditions this summer will result in low crop yield in much of Iowa, and weather forecasts call for normal or below normal rainfall through the fall. These dry conditions and low yields will significantly reduce phosphorus (P) and potassium (K) removal with crop harvest, and may also affect soil test P, K and pH results, complicating test interpretations.


Phosphorus - Why The Concern About Water Quality?, John Creswell, Antonio P. Mallarino, Gerald A. Miller, John E. Sawyer, Michael J. Tidman 2017 Iowa State University

Phosphorus - Why The Concern About Water Quality?, John Creswell, Antonio P. Mallarino, Gerald A. Miller, John E. Sawyer, Michael J. Tidman

John E. Sawyer

This article concludes a series that provides producers with information to help with on-farm management of phosphorus (P) and in understanding the complex economic and environmental issues involved in P management. This article discusses potential regulatory action and offers options to help producers move toward compliance. Iowa has many water quality challenges. It may be helpful to take a step back from the science of water quality and review the politics of water quality. What are some potential regulations and what can producers do to be in compliance?


Nitrogen Loss—Spring 2013, John E. Sawyer 2017 Iowa State University

Nitrogen Loss—Spring 2013, John E. Sawyer

John E. Sawyer

Dry soils across Iowa from deficit precipitation following the drought in 2012 have changed to excess wetness this spring. Unfortunately, precipitation to replenish subsoil moisture has been much more than needed. As I wrote in an ICM News article earlier this spring, one downside to the excess precipitation has been movement of carryover nitrate deeper into the profile and to tile lines, resulting in high nitrate-N concentrations in surface waters. This means there is less nitrate-N carryover to be utilized by 2013 crops, although as noted in the previous article, not all of the carryover N moved below the three-foot ...


The Future Of Evapotranspiration: Global Requirements For Ecosystem Functioning, Carbon And Climate Feedbacks, Agricultural Management, And Water Resources, Joshua B. Fisher, Forrest Melton, Elizabeth Middleton, Christopher Hain, Martha Anderson, Richard Allen, Matthew McCabe, Simon Hook, Dennis Baldocchi, Philip A. Townsend, Ayse Kilic, Kevin Tu, Diego Miralles, Johan Perret, Jean-Pierre Lagouarde, Duane Waliser, Adam J. Purdy, Andrew French, David Schimel, James S. Famiglietti, Graeme Stephens, Eric F. Wood 2017 California Institute of Technology

The Future Of Evapotranspiration: Global Requirements For Ecosystem Functioning, Carbon And Climate Feedbacks, Agricultural Management, And Water Resources, Joshua B. Fisher, Forrest Melton, Elizabeth Middleton, Christopher Hain, Martha Anderson, Richard Allen, Matthew Mccabe, Simon Hook, Dennis Baldocchi, Philip A. Townsend, Ayse Kilic, Kevin Tu, Diego Miralles, Johan Perret, Jean-Pierre Lagouarde, Duane Waliser, Adam J. Purdy, Andrew French, David Schimel, James S. Famiglietti, Graeme Stephens, Eric F. Wood

Papers in the Earth and Atmospheric Sciences

The fate of the terrestrial biosphere is highly uncertain given recent and projected changes in climate. This is especially acute for impacts associated with changes in drought frequency and intensity on the distribution and timing of water availability. The development of effective adaptation strategies for these emerging threats to food and water security are compromised by limitations in our understanding of how natural and managed ecosystems are responding to changing hydrological and climatological regimes. This information gap is exacerbated by insufficient monitoring capabilities from local to global scales. Here, we describe how evapotranspiration (ET) represents the key variable in linking ...


Effect Of Sulfur And Manure On Availability Of Rock Phosphate In Soil, P. E. Brown, A. R. Gwinn 2017 Iowa State College

Effect Of Sulfur And Manure On Availability Of Rock Phosphate In Soil, P. E. Brown, A. R. Gwinn

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The use of phosphorus fertilizers is now a recognized necessity in all systems of permanent agriculture. However well supplied naturally, all soils gradually become depleted in phosphorous thru the removal of crops and this element must be returned if crop production is to continue satisfactory. Many soils, especially those under long continued cultivation, have been found to respond very profitably to phosphorus fertilization while even the newer, more fertile soils are approaching a condition where phosphorus will soon become the controlling factor of growth. The interest in phosphorus fertilizers is therefore becoming more widespread and the use of these materials ...


Carbon Dioxide Production In Soils And Carbon And Nitrogen Changes In Soils Variously Treated, R. S. Potter, R. S. Snyder 2017 Iowa State College

Carbon Dioxide Production In Soils And Carbon And Nitrogen Changes In Soils Variously Treated, R. S. Potter, R. S. Snyder

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The carbon dioxide of the soil atmosphere, along with the water, has long been recognized as the most active agent in the decomposition of comparatively inert minerals to give available and soluble plant food material. It is probable that herein lies the great benefit which comes from the application to soil of organic material which not only increases the energy material easily available for the bacteria, but also improves the physical condition of the soil. This in turn increases bacterial activity, which gives rise to increased carbon dioxide production.

At the Iowa Agricultural Experiment Station, for some time past, both ...


Influence Of Humus Forming Materials Of Different Nitrogen-Carbon Ratios On Bacterial Activities, P. E. Brown, F. E. Allison 2017 Iowa State College

Influence Of Humus Forming Materials Of Different Nitrogen-Carbon Ratios On Bacterial Activities, P. E. Brown, F. E. Allison

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The determination of the nitrogen-carbon ratio in soils is now considered of much importance in fertility studies. Not only does it show the organic matter content of soils more accurately than the more or less arbitrary humus determinations, concerning which considerable difference of opinion exists, but it also throws some light on the rate at which decomposition processes are occurring.


The Effect Of Some Manganese Salts On Ammonification And Nitrification, P. E. Brown, G. A. Minges 2017 Iowa State College

The Effect Of Some Manganese Salts On Ammonification And Nitrification, P. E. Brown, G. A. Minges

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Manganese occurs in practically all soils, but the quantities present are exceedingly variable. Twenty-six typical soils analyzed by Robinson showed the presence of manganese in amounts varying from 0.01 to 0.51 per cent of MnO. Other studies have shown the occurrence of very large amounts in certain soils, but the average of 0.071 per cent MnO given in the work referred to above probably represents fairly accurately the manganese content of normal soils in this country.


Studies In Sulfofication, P. E. Brown, H. W. Johnson 2017 Iowa State College

Studies In Sulfofication, P. E. Brown, H. W. Johnson

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Recent experiments have shown that sulfofication or sulfuroxidation is an important process occurring in field soils. Plants have been found to require considerable amounts of sulfates for their best growth and inasmuch as sulfur is not present in soils in that form, but as unassimilable organic and inorganic compounds, the sulfur-feeding of crops will depend very largely upon the ability of a soil on which they grow to produce sulfates from these unavailable substances. In other words, the total sulfur content of a soil, alone, will not show the sulfur available for plant growth. The sulfofying power of the soil ...


Oysters And Mammoths: Fossils In Central Texas–Texas Academy Of Science 2017, Chris Barker, R. LaRell Nielson 2017 Stephen F Austin State University

Oysters And Mammoths: Fossils In Central Texas–Texas Academy Of Science 2017, Chris Barker, R. Larell Nielson

Faculty Publications

Texas Academy of Science, 2017 Field Trip

This year's Texas Academy of Science Geology Field Trip takes you to two very different fossil sites in central Texas. Stop 1 is along a quiet road in the Hill Country where you can collect abundant invertebrate fossils from the Lower Cretaceous Comanche Peak Limestone and Walnut Clay. The second stop of the trip is at one of the newest units of America's park service: the Waco Mammoth National Monument. At this site you will see a spectacular fossil discovery that is now one of the main mammoth sites in North ...


Young Earth Flood Geology In The Grand Canyon, John H. Whitmore 2017 Cedarville University

Young Earth Flood Geology In The Grand Canyon, John H. Whitmore

Science and Mathematics Faculty Publications

No abstract provided.


Bacterial Activities And Crop Production, Percy Edgar Brown 2017 Iowa State College

Bacterial Activities And Crop Production, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Until the present time studies in soil bacteriology have dealt almost exclusively with the occurrence and activities of microorganisms in the soil and no attempt has been made to interpret experimental results from the standpoint of crop production. This is due, of course, to the fact that as a science soil bacteriology is scarcely out of its infancy and the preliminary investigations in any science must of necessity deal mainly with underlying principles and such studies are always apt to be rather fragmentary in character.


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