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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.


Determination Of Amino Acids And Nitrates In Soils: Amino Acids, Ammonia And Nitrates In Manured And Limed Soil, R. S. Potter, R. S. Snyder 2017 Iowa State College

Determination Of Amino Acids And Nitrates In Soils: Amino Acids, Ammonia And Nitrates In Manured And Limed Soil, R. S. Potter, R. S. Snyder

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

In view of the fact that no data had ever been obtained on the quantitative relationships of the organic material in the soil by such methods as would preclude a chemical transformation, two things seemed desirable, in continuing the humus investigations at the Iowa Agricultural Experiment Station. First, to attempt the analysis of the organic material of the soil without subjecting it to hydrolysis or other chemical change, and second, to correlate the proportionate quantities of the compounds or classes of compounds found with the kind of soil, its history, treatment, fertility, etc.


Sulfofication In Soils, P. E. Brown, E. H. Kellogg 2017 Iowa State College

Sulfofication In Soils, P. E. Brown, E. H. Kellogg

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Sulfur has long been known to be one of the essential plant food constituents. It has always been believed, however, that there was sufficient present in all soils for the optimum growth of crops. This assumption has been very largely based on Wolff's analyses of the ashes of various crops which showed the presence of very small amounts of sulfur.

The recent work of many investigators has demonstrated, however, that the amount of sulfur in plant materials as determined in the ash is, in most cases, entirely too low; that there is a considerable loss of sulfur in the ...


Bacteriological Studies Of Field Soils, Iii. The Effects Of Barnyard Manure, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, Iii. The Effects Of Barnyard Manure, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

The conclusions which may be drawn from the experiments upon the effects of barnyard manure on bacteriological activities of field S'oils presented in this bulletin are as follows:

1. Applications of manure up to sixteen tons per acre increased the numbers of organisms in the soil as shown by the growth on modified synthetic and albumen agar. The ammonifying power of the soil as shown by tests with the casein-fresh soil, albumen-fresh soil, dried blood-fresh soil, and dried blood-air-dried soil methods, and the nitrifying power tested by the ammonium sulfate-fresh soil, and the ammonium sulfate-air- dried soil methods were ...


Response Of A Small Population Of Greater Sage-Grouse To Tree Removal: Implications Of Limiting Factors, S. Nicole Frey, Rachel Curtis, Kevin Heaton 2017 Utah State University

Response Of A Small Population Of Greater Sage-Grouse To Tree Removal: Implications Of Limiting Factors, S. Nicole Frey, Rachel Curtis, Kevin Heaton

Kevin Heaton

In Utah, greater sage-grouse (Centrocercus urophasianus; hereafter, sage-grouse) range has been reduced to 50% of what is considered historical availability due to habitat degradation and loss. In an effort to improve sage-grouse habitat in southern Utah, the U.S. Bureau of Land Management (BLM) conducted a tree-removal treatment in 2005. We conducted a study to determine if (a) the tree-removal treatment was effective at creating new sage-grouse habitat, and (b) if characteristics of used habitat were similar to those reported in previous literature. The treatment resulted in increased abundance of grasses and forbs. Additionally, shrub percentage cover and height was ...


Methods For The Bacteriological Examination Of Soils, Percy Edgar Brown 2017 Iowa State College

Methods For The Bacteriological Examination Of Soils, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

Because the idea of examining soils bacteriologically owed its inception to the development of the gelatine plate method for isolating pure cultures, very naturally the first investigations of soil bacteria were by the use of plate cultures. the studies, therefore, were purely quantitative in nature. The results secured by the pioneers in this work demonstrated some facts of considerable interest, but it soon became evident that mere quantitative determinations of the bacteria in soils were inadequate to give information regarding the relation of such organisms and their activities to the fertility of the soil.


Amino Acids And Acid Amides As Sources Of Ammonia In Soils, S. L. Jodidi 2017 Iowa State College

Amino Acids And Acid Amides As Sources Of Ammonia In Soils, S. L. Jodidi

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

l'he nitrogen recognized as one of the most important elements for plants, if not the most necessary, is being studied and discussed by many investigators ana among them the opinion is quite general that there is a considerable difference between the various forms of nitrogen. this is particularly true of soil nitrogen. Wile in some soils the nitrogen is readily ammonified and furter ifled and further oxidized to nitrites and nitrates, it does not undergo those processes in other soils. In other words, soil nitrogen is available or can easily be made available for plants in some cases, in ...


Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown 2017 Iowa State College

Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. In the different soil types, as well as in the same soil under different rotations, the greatest number of organisms occurred at a depth of 4 inches.

2. Bacteria were found in considerable numbers at much lower depths in the loess soil than in the drift soil.

3. There was a more or less gradual decrease in numbers to a depth of 3, 5 and in one case of fifteen feet. No sudden increases were observed even where gains in moisture occurred.

4. The greatest decrease in numbers of organisms occurred within the first 12 inches and in some ...


Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

From a bacteriological study of soil plots under both continuous cropping and various crop rotations, these general conclusions were drawn:

1. The rotation of crops caused the development of greater numbers of organisms in the soil and of greater ammonifying, nitrifying, and nitrogen-fixing power by the soil, than continuous cropping either to corn or to clover.

2. Greater numbers of organisms, greater ammonifying, nitrifying, and nitrogen-fixing powers were found in a soil under a three year rotation of corn, oats, and clover, than in a soil under a two year rotation of corn and oats, or in a soil under ...


Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown 2017 Iowa State College

Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. Applications of limestone up to three tons per acre increased the total number of soil bacteria which develop on "modified synthetic" agar plates.

2. These increases probably occurred in species more resistant to drought.

3. The three ton application gave a proportionately greater increase in numbers than the two tons.

4. Application of limestone up to three tons per acre increased the ammonlfying, the nitrifying, anil the nitrogen fixing powers of the soil.

5. The ammonification of dried blood and cottonseed meal did not run parallel in tests of field soils subjected to continued drought.

6. The three ton ...


Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith 2017 Iowa State College

Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

1. By means of the" modified synthetic" agar plate method bacteria are shown to be present in large numbers in a typical Wisconsin drift soil when it is completely frozen and the temperature is below zero degrees Centigrade; furthermore, increases and decreases in numbers of organisms occur during this period and large numbers are found after the soil has been frozen for a considerable period than before it begins to freeze.

2. During the fall season, the number of bacteria present in the soil diminishes gradually with the lowering of the temperature.

3. Frozen soils possess a much greater ammonifying ...


The Chemical Nature Of The Organic Nitrogen In The Soil: Influence Of Various Factors On Decomposition Of Soil Organic Matter, S. L. Jodidi 2017 Iowa State College

The Chemical Nature Of The Organic Nitrogen In The Soil: Influence Of Various Factors On Decomposition Of Soil Organic Matter, S. L. Jodidi

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

It was shown in previou' publications that the acid-soluble organic nitrogen in Iowa soils as well as in Michigan peat soils is composed chiefly of acid amides, monamino acids and diamino acids. Following those publications, and also before, other papers appeared, dealing with the isolation of organic nitrogenous compounds from soils. Thus Schreiner and Shorey succeeded in isolating from various soils, in addition to a number of non-nitrogenous bodies, the diamino acids, arginine and histidine, as well as the pyrimidine derivative, cystosine and the purine bases, xanthine and hypoxanthine. Prior to that Shorey extracted from Hawaiian soils a compound which ...


Some Bacteriological Effects Of Liming, Percy Edgar Brown 2017 Iowa State College

Some Bacteriological Effects Of Liming, Percy Edgar Brown

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

These experiments were undertaken to determine the effects of liming on certain groups of soil bacteria in a typical Wisconsin drift soil. They justified the following general conclusions:

1. Applications of lime up to three tons per acre lead to an increase in the numbers of bacteria developing on "modified synthetic" agar. They also produce an increase in ammonification, nitrification, and in nitrogen fixation when these processes are tested by the beaker method. These increases are in all cases almost proportionate to the amount of lime applied.

2. Natural increases in numbers of bacteria tend to obscure the effects of ...


The Chemical Nature Of The Organic Nitrogen In The Soil, S. L. Jodidi 2017 Iowa State College

The Chemical Nature Of The Organic Nitrogen In The Soil, S. L. Jodidi

Research Bulletin (Iowa Agriculture and Home Economics Experiment Station)

It is safe to say that among the elements which are essential for plant life, nitrogen plays the most prominent part. While nitrogen is considered to be one of the most useful constituents of soil organic matter or humus, it is the available nitrogen which is of especial value. The data given in this bulletin as well as in previous publications, show, in agreement with numerous investigations by others, that the amount of ammonia in soils is quite small, ranging from a few thousandths to a few hundredths of one per cent.


A Survey Of Weed Varieties In Samanabad, Lahore, Sadaf Nazir, Beenish Zia Butt, Anjum Navid 2017 Government Post-Graduate College for Women, Samanabad, Pakistan

A Survey Of Weed Varieties In Samanabad, Lahore, Sadaf Nazir, Beenish Zia Butt, Anjum Navid

Journal of Bioresource Management

A weed is an herbaceous plant that grows as a wild plant, and is considered a hindrance in the growth of preferred vegetation or cumbering the ground, and has no value for beauty or use. However, some weeds have roles in medicine, ecology and many other fields. A survey was conducted in Lahore to observe the weed varieties present in the area of Samanabad. The present study was carried out in May and June 2014.The primary purpose of the study was to gain knowledge about the availability of the total number of species present in this area. We also ...


Bat Urea-Derived Minerals In Arid Environment. First Identification Of Allantoin, C4H6N4O3, In Kahf Kharrat Najem Cave, United Arab Emirates, Philippe Audra, Pavel Bosák, Fernando Gázquez, Didier Cailhol, Roman Skála, Lenka Lisá, Šárka Jonášová, Amos Frumkin, Martin Knez, Tadej Slabe, Nadja Zupan Hajna, Asma Al-Farraj 2017 University of Nice Sophia-Antipolis

Bat Urea-Derived Minerals In Arid Environment. First Identification Of Allantoin, C4H6N4O3, In Kahf Kharrat Najem Cave, United Arab Emirates, Philippe Audra, Pavel Bosák, Fernando Gázquez, Didier Cailhol, Roman Skála, Lenka Lisá, Šárka Jonášová, Amos Frumkin, Martin Knez, Tadej Slabe, Nadja Zupan Hajna, Asma Al-Farraj

International Journal of Speleology

Kahf Kharrat Najem Cave is a small cave in United Arab Emirates (UAE) that hosts a bat colony which is the source of guano deposits and peculiar centimeter-long yellowish stalactites. The mineralogy and geochemistry of these deposits were analyzed using powder X-ray diffraction (XRD), energy dispersive X-ray spectroscopic microanalysis (EDX), scanning electron microscope (SEM), and stable isotope composition (δ13C and δ15N). Urea CO(NH2)2 was found to be the main compound of these stalactites, while allantoin C4H6N4O3 was found to be an accessory urea byproduct. This paper ...


2016 Data Collected For Resistivity, Magnetic Susceptibility And Sediment Characterization Of The York River Estuary, Va In Support Of The Empirical Investigation Of The Factors Influencing Marine Applications Of Emi (Year 2 Of Serdp Project Mr-2409), Grace M. Massey, Carl T. Friedrichs 2017 Virginia Institute of Marine Science

2016 Data Collected For Resistivity, Magnetic Susceptibility And Sediment Characterization Of The York River Estuary, Va In Support Of The Empirical Investigation Of The Factors Influencing Marine Applications Of Emi (Year 2 Of Serdp Project Mr-2409), Grace M. Massey, Carl T. Friedrichs

VIMS Data

The objective of this component of the Strategic Environmental Research and Development Program (SERDP) Project MR-2409 was to conduct field measurements to aid in the determination of the electromagnetic induction (EMI) response to the water column and underlying sediments in the York River estuary, which includes water column and sediment properties similar to many underwater environments of interest to unexploded ordinance detection. Data and samples from a standard suite of hydrographic and sedimentological measurements, as well as electrical resistivity and magnetic susceptibility, were collected and analyzed for each location. These cruises provided opportunities to obtain information that is being used ...


Putting Local Knowledge And Context To Work For Gunnison Sage-Grouse Conservation, Corrine Noel Knapp, James Cochran, F. Stuart Chapin III, Gary Kofinas, Nathan Sayre 2017 University of Alaska

Putting Local Knowledge And Context To Work For Gunnison Sage-Grouse Conservation, Corrine Noel Knapp, James Cochran, F. Stuart Chapin Iii, Gary Kofinas, Nathan Sayre

Human–Wildlife Interactions

Successful conservation requires adequate understanding of focal species and ecology, practices that may assist species survival, and a community of people willing and able to conserve the species. For many species at risk, we operate with imperfect knowledge in complex conservation contexts. In this case study involving the Gunnison sage-grouse (Centrocercus minimus), we interviewed 26 community-defined local experts, including both those with and without related academic degrees, to assess the utility of local knowledge for understanding and informing conservation opportunities.This project suggests several benefits of integrating local knowledge that apply specifically to rare and endemic populations, including the ability ...


Murray Energy Corporation V. Mccarthy, Sarah M. Danno 2017 University of Montana School of Law

Murray Energy Corporation V. Mccarthy, Sarah M. Danno

Public Land and Resources Law Review

Holding that the widespread effects of environmental regulation on the coal industry constituted sufficient importance, the Northern District of West Virginia ordered the Environmental Protection Agency to conduct analysis on employment loss and plant reduction resulting from regulatory effects. In admonishing the EPA’s inaction, the court ruled that the Agency had a non-discretionary duty to evaluate employment and plant reduction. Furthermore, the court held that the EPA’s attempt to put forth general reports in place of required evaluations was an invalid attempt to circumvent its statutory duty.


So, You Want To 3d Print A Landscape? An Outline Of Some Methods, Dylan J. McKevitt, Thomas L. Rice, Emily Jackson, Victoria Couser 2017 Cedarville University

So, You Want To 3d Print A Landscape? An Outline Of Some Methods, Dylan J. Mckevitt, Thomas L. Rice, Emily Jackson, Victoria Couser

Thomas L. Rice, M.E.

No abstract provided.


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