Methods For The Bacteriological Examination Of Soils, 2017 Iowa State College
Methods For The Bacteriological Examination Of Soils, Percy Edgar Brown
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, 2017 Iowa State College
Amino Acids And Acid Amides As Sources Of Ammonia In Soils, S. L. Jodidi
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, 2017 Iowa State College
Bacteria At Different Depths In Some Typical Iowa Soils, Percy Edgar Brown
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, 2017 Iowa State College
Bacteriological Studies Of Field Soils, Ii. The Effects Of Continuous Cropping And Various Rotations, Percy Edgar Brown
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, 2017 Iowa State College
Bacteriological Studies Of Field Soils, I. The Effects Of Lime, Percy Edgar Brown
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, 2017 Iowa State College
Bacterial Activities In Frozen Soils, Percy Edgar Brown, Roy Eugene Smith
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
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, 2017 Iowa State College
Some Bacteriological Effects Of Liming, Percy Edgar Brown
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, 2017 Iowa State College
The Chemical Nature Of The Organic Nitrogen In The Soil, S. L. Jodidi
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.
Closing The Water Budget In An Experimental Urban Watershed: A Comparative Assessment Of Methods For Measuring Evapotranspiration, Leana M. Weissberg, Gaboury Benoit
Yale Day of Data
No abstract provided.
Evaluating The Impact Of Natural And Agricultural Ecosystems On Soil Properties In Western Kentucky., 2016 Murray State University
Evaluating The Impact Of Natural And Agricultural Ecosystems On Soil Properties In Western Kentucky., Cody Masterson
No abstract provided.
Predicting Post-Fire Change In West Virginia, Usa From Remotely-Sensed Data, 2016 West Virginia University
Predicting Post-Fire Change In West Virginia, Usa From Remotely-Sensed Data, Michael Strager P. Strager, Melissa Thomas-Van Gundy, Aaron E. Maxwell
Journal of Geospatial Applications in Natural Resources
Prescribed burning is used in West Virginia, USA to return the important disturbance process of fire to oak and oak-pine forests. Species composition and structure are often the main goals for re-establishing fire with less emphasis on fuel reduction or reducing catastrophic wildfire. In planning prescribed fires land managers could benefit from the ability to predict mortality to overstory trees. In this study, wildfires and prescribed fires in West Virginia were examined to determine if specific landscape and terrain characteristics were associated with patches of high/moderate post-fire change. Using the ensemble machine learning approach of Random Forest, we determined ...
Landform Mapping Of The Clarks River Alluvial System Using Lidar Dems, 2016 Murray State University
Landform Mapping Of The Clarks River Alluvial System Using Lidar Dems, Benedict W. Ferguson
The Clarks River is located in western Kentucky near the city of Benton. It travels through and weathers lacustrine or lake deposits as well as fluvial or river deposits. These deposits are also overlain by loess deposited from the last glacial maximum. Historically, people have taken advantage of these rich deposits for agriculture which has led to increased settlement. With increased settlement, the river has experienced alteration. The west fork of the Clarks River has been channelized while the east fork of the Clarks River has managed to remain un-channelized and has since been allowed to run relatively freely.
Mapping The Variability Of Soil Quality Indicators In Natural Versus Agricultural Ecosystems, Mary G. Derting Miss
Traditionally, Kentucky agriculture has focused on crop production and soil fertility while overlooking soil quality and its dependence on land management type. This research attempted to reveal the importance of land management types and their individual effects on physical soil quality indicators. The second objective of this study was to show the variance of physical soil quality indicators across different land managements by using layered maps. Such visual representation of the data along with statistical analysis also showed which soil quality parameters are more sensitive to change in land management type. Land management types included three undisturbed grassland and undisturbed ...
Identifying Soil Constraints That Limit Wheat Yield In The South-West Of Western Australia, 2016 Department of Agriculture and Food, Western Australia
Identifying Soil Constraints That Limit Wheat Yield In The South-West Of Western Australia, Dennis Van Gool
Resource Management Technical Reports
This is a novel approach using regional-scale information. The analysis estimated that:
- most of the wheat-growing land in south-west WA has one or more soil constraints
- about 1.6 million hectares (9% of the total area) are not suitable for cropping
- about 2.2 million hectares (12% of the total area) are suitable for cropping but are subject to many (more than 3) constraints; soil amelioration is unlikely to significantly improve profitable yield gain
- subsurface acidity extends over 12.6 million hectares (about 70% of the total area); about 7.6 million hectares of that area (42% of the total ...
Identifying Groundwater - Dependent Wetlands Of The Broome Sandstone Aquifer In The La Grange Groundwater Area, 2016 Department of Agriculture and Food
Identifying Groundwater - Dependent Wetlands Of The Broome Sandstone Aquifer In The La Grange Groundwater Area, Nicholas Wright, Richard J. George Dr, Robert Paul, Paul Raper
Resource Management Technical Reports
This report identifies wetlands that are likely to be dependent on the Broome Sandstone aquifer within the La Grange groundwater allocation area. The Broome Sandstone aquifer is the dominant groundwater resource in the area. With potential agricultural growth of this area, it is necessary to understand, monitor and manage the aquifer and its dependent wetlands. This report describes how we created a watertable surface that was used to identify wetlands and to determine which of the previously mapped wetlands are likely to be sourced from the Broome Sandstone aquifer. A watertable surface was created from 148 points taken from bore ...
Sensitivity Of Seven Diverse Speciesto Blue And Green Light: Interactions With Photon Flux, 2016 Utah State University
Sensitivity Of Seven Diverse Speciesto Blue And Green Light: Interactions With Photon Flux, Michael Chase Snowden, Bruce Bugbee, Kevin R. Cope
Plants, Soils, and Climate Faculty Publications
Despite decades of research, the effects of spectral quality on plant growth, and development are not well understood. Much of our current understanding comes from studies with daily integrated light levels that are less than 10% of summer sunlight thus making it difficult to characterize interactions between light quality and quantity. Several studies have reported that growth is increased under fluorescent lamps compared to mixtures of wavelengths from LEDs. Conclusions regarding the effect of green light fraction range from detrimental to beneficial. Here we report the effects of eight blue and green light fractions at two photosynthetic photon fluxes (PPF ...
Pindan Soils In The La Grange Area, West Kimberley: Land Capability Assessment For Irrigated Agriculture, 2016 Department of Agriculture and Food, Western Australia
Pindan Soils In The La Grange Area, West Kimberley: Land Capability Assessment For Irrigated Agriculture, Henry J. Smolinski, Paul Galloway, Justin Laycock
Resource Management Technical Reports
This report identifies areas of Pindan country along the Great Northern Highway, south of Broome from Roebuck to Mandora, which have high potential for irrigated agriculture. The area contains significant reserves of potable groundwater defined by the La Grange groundwater allocation area, which is based on the surficial Broome Sandstone aquifer.
Over the past 30 years, several small- to medium-scale irrigation developments have been successfully established in the region. The water opportunities project aims to identify and quantify the land and water resources of the region to ensure any future expansion of irrigated agriculture is sustainable and will not have ...
Simple Soil Quality Tests And Organic Management Practices For Orchards In The Intermountain West, 2016 Utah State University
Simple Soil Quality Tests And Organic Management Practices For Orchards In The Intermountain West, Esther Oline Thomsen
All Graduate Theses and Dissertations
Soil quality problems such as erosion, depleted soil organic matter, salinity, depleted or excessive nutrient reserves and reduced water holding capacity are of increasing concern to farmers in the Intermountain West. Marginal soils require higher rates of fertilizers and other amendments to meet crop needs. As input costs rise and water resources are increasingly limited, simple and effective methods for evaluating and improving soil quality and fertility are of growing importance. Practices known to improve soil quality include reduced to no tillage, cover crop use- especially legumes, and addition of mulch and other carbon rich amendments. Comprehensive soil quality testing ...
Trapping Fecal Bacteria And Sediment In Surface Runoff From Cropland Treated With Poultry Litter, 2016 University of Kentucky
Trapping Fecal Bacteria And Sediment In Surface Runoff From Cropland Treated With Poultry Litter, Mark S. Coyne, R. A. Gilfillen, Robert L. Blevins
Mark S. Coyne
Between 1991 and 1994 the broiler population exploded in Kentucky as the poultry industry began to expand. The Kentucky Department of Agriculture predicts that within four years annual broiler production could exceed 275 million birds. This may be good for Kentucky's economy but it carries some important environmental consequences. If expansion continues as anticipated, the estimated waste production from broilers for processing could reach 300,000 tons per year (assuming each broiler house produces 150,000 birds per year and the yearly manure and litter production per house is approximately 160 tons).