bluuebunny/crossref_metadata_2025_split huggingface dataset:
Rationale for Optimum Nitrogen Fertilization in Corn Production
Authors: Stanford George 
Published: July 2010

AbstractDuring the past decade, the percentage of the corn (Zea mays L.) acreage in the USA receiving N fertilizer has risen steadily. By 1971, in the Corn Belt and five adjoining states, this proportion ranged from 93 to 100% of the total corn acreage. Between 1964 and 1970 the average rate of N applied to fertilized acres increased about 83% in the Corn Belt and 128% in adjacent states (Nebraska, Kansas, Michigan, Wisconsin, and Minnesota). Undoubtedly, there has been an accompanying increase in the proportion of the corn acreage receiving optimum to excessive amounts of N fertilizer. These trends emphasize the importance of developing improved procedures for achieving optimum fertilizer N use (i.e., adequate but not excessive rates, and proper timing for greater efficiency) consistent with the goal of minimizing the possibility of environmental pollution.The basic information required in predicting optimum use of N includes: (i) the internal N requirement of the crop for expected attainable yield, (ii) the amount of soil N mineralized during the cropping season, (iii) the amount of residual mineral N present the root zone early in the cropping season, and (iv) the expected efficiency of recovery of the plant‐available N supply. With good management, efficiency, or % recovery of applied N by the grain and stover often is in the range of 50 to 70%. In this range, at near‐optimum rates of N, essentially all of the unrecovered fertilizer N is subject to immobilization during decomposition of plant residues (stover and roots). At higher than optimum rates, however, a significant portion of the nitrate remains mobile and susceptible to loss by leaching or denitrification.
Integrated Systems for Utilizing Waste Heat from Steam Electric Plants
Authors: Boersma L. , Rykbost K. A. 
Published: July 2010

AbstractMultiple use of waste heat and cooling waters from power plants will become an important consideration in the development, siting, and certification of these plants. The heat in the cooling water must be considered a resource to be managed for effective use. At the same time, society faces problems of degradation of its environment caused by industries, by individuals, and by communities. Pollution problems such as disposal of agricultural and domestic sewage, calefaction, and use of persistent chemicals must be solved in concert, not individually. The ultimate solution to these problems must be found in the development of integrated systems in which resources are not used in a destructive manner but are recycled. These observations prompted the development of a system of components that can beneficially utilize waste heat, allow multiple use of the cooling water, and achieve a high degree of efficiency in the production of food and fiber without causing polluted streams and soils. The concept fits anticipated trends in agriculture where a higher rate of production per unit area must be achieved for economic reasons and to avoid some of the ecological impact. It allows wise land‐use planning which is rapidly emerging as a major national issue. A statement of the problem is presented, the magnitude of the present and future rate of waste heat production is considered, and criteria for the use of waste heat are introduced. Certain aspects of the feasibility of the proposed integrated systems are evaluated.
Ecological Management of Thermal Discharges
Authors: Oswald W. J. 
Published: July 2010

AbstractHeat from thermal discharges may improve sewage, animal and vegetable waste treatment processes. With sufficient heat, human, animal, and vegetable wastes may be subject to methane fermentation and algal growth the year around. Algae produced on human and animal waste may be used for livestock feed. The algae produced on vegetable wastes may be processed for human food. Following algae production, the waste water is hygienic and suitable for parks. The rate of anaerobic fermentation in ponds increases 30‐fold between 15C and 35C. The most promising algae, Scenedesmus quadricauda, grows best at 20C. Waste decomposition and protein production rates exceed 100 times those normally found in nature. Algae ponds gain and lose heat at rates exceeding those found in ponds free of algae. Calcium and magnesium removal in algal ponds reaches 50% of influent. Intensive research on such integrated systems is recommended.
Conceptual Design of a Food Complex Using Waste Warm Water for Heating
Authors: Beall S. E. 
Published: July 2010

AbstractThe US Atomic Energy Commission has supported a small program at the Oak Ridge National Laboratory (ORNL) to determine (i) how the heat in waste warm water from electric generating plant condensers can be transferred economically to controlled environments, such as in greenhouses or animal enclosures; and (ii) to suggest, in a conceptual effort, how the heat exchange system could be applied to an intensive food production complex which might be constructed near a power station. A heat‐using complex consisting of enclosures for fish, poultry, swine, and vegetable plants has been conceived with the goal of maximizing the use of heat and the wastes from the various operations by recycling. It is hoped that the concept will prove to be sufficiently attractive that a utility or an agribusiness company will undertake a small demonstration based on some of these ideas.
Simulation Model to Study the Utilization of Waste Heat Using a Combination Multiple Reservoir and Greenhouse Complex
Authors: Price D. R. , Peart R. M. 
Published: July 2010

AbstractA system designed to utilize waste heat discharged by the cooling condenser of a steam‐electric generating station is investigated using system analysis techniques. Much of the analysis is carried out with the assistance of computer simulation of the total system.The system under study involves the use of multiple reservoirs for storage, utilization, and dissipation of the thermal discharge from a 1000‐megawatt generating station. One reservoir is used for storage of the warmest water to be used for heating of a greenhouse located adjacent to the reservoir. A second reservoir is included and used for commercial fish production, while another is used for recreational purposes and provides the necessary cooling capacity for summer cooling.Mathematical models are developed to describe the heat exchange characteristics of the reservoirs and greenhouse. A descriptive model is added to describe and define the detailed operating conditions of the total system. These models are incorporated into a computer simulation model which is used in the analysis.The study includes an investigation of simulation languages available for simulation of large scale systems. The special purpose language, DYNAMO, is selected and used for the simulation tests. The development and coding of the computer program are discussed in detail.Sensitivity analysis is used to study the behavior of the system with variations in the design and operation. Operating ranges are determined for the various components of the system. The simulator is used to study the operation of the system throughout a 1‐year simulation period.The simulation model uses actual weather data in the computations to determine heat exchange within the reservoirs and the greenhouse. A study of the effect of the level of aggregation of the weather data is included. The computer simulator is used as a tool for developing a control system to automatically control the real world system. A description of the control system including a circuit design is included.The simulator is used to show that a 2,500‐acre recreational lake, up to 500 acres of reservoir for fish production, and up to 350 acres of greenhouse make up a feasible system design.
Waste Accumulation on a Selected Dairy Corral and Its Effect on the Nitrate and Salt of the Underlying Soil Strata
Authors: Chang A. C. , Adriano D. C. , Pratt P. F. 
Published: July 2010

AbstractThe improvement of animal waste handling and treatment techniques depends upon understanding animal waste production and distribution patterns in a confined area. A corral was selected from a typical Chino‐Corona, California area dairy to study waste accumulation and distribution on corral surfaces and to determine its effect on underlying soil strata. Waste deposited on the surface tended to accumulate in a small area of the corral; as much as 57% of the waste was in an area equaling 30% of the total corral surface. Considerable decomposition of organic matter and nitrogen loss took place during accumulation; however, collected waste samples were relatively unstable and subject to further decomposition. After a long period of dairy operations, leaching of nitrates, chlorides, and organic matter into soils was substantial. The same order of magnitude of leaching of chloride and organic carbon occurred throughout the entire corral surface. The amount of nitrate underneath the area of heavy waste accumulation was less than that in the other part of the corral. An apparent unfavorable condition developed for nitrogen transformations that reduced the amount of nitrogen subject to leaching. Future improvement in dairy waste management should take this into consideration in order to minimize its potential cause of ground water pollution.
Distribution and Chemistry of Phosphorus in an Albaqualf Soil After 82 Years of Phosphate Fertilization
Authors: Kao C. W. , Blanchar R. W. 
Published: July 2010

AbstractThe distribution of P in a fertilized and unfertilized Mexico silt loam soil was measured. After 82 years of P fertilization, the added P was found in Ap (0–23 cm), smaller amounts in the A and B, and B2 (23–86 cm), and large amounts in the B3 and upper C (86–137 cm) horizons. In the fertilized soil the distribution of P, particularly inorganic and available, was similar to that of original P in the soil profile.The P adsorption capacities of fertilized and unfertilized soils were similar. These data indicated that the soil fertilized with P for 82 years had nearly double the total P content, but the ability of the soil to adsorb additional P was the same. Ion products indicated that the P level in the soil solution was controlled by the solubility of strengite.
Uptake and Distribution of Carbofuran and Its Metabolites in Field‐Grown Corn Plants
Authors: Turner Benjamin C. , Caro Joseph H. 
Published: July 2010

AbstractCarbofuran was applied to two experimental watersheds in broadcast and row application to study the uptake, distribution, and metabolism of the insecticide in corn (Zea mays L.). Plants were sampled at both silage and harvest stages and plant parts were analyzed separately. Pesticide concentrations in the crop grown on the row application watershed were higher than those on the broadcast field, reflecting differences in treatment rates. Plants at harvest contained substantially lower residues than at the silage stage. Residues were concentrated in the leaves, with lesser amounts in the stalks and cobs and only traces in the grain. In the leaves, over 90% of the carbofuran was metabolized to 3‐hydroxycarbofuran and 3‐oxocarbofuran, the former constituting 80 to 95% of the total metabolite content. Intact carbofuran predominated in the stalks and cobs. Although application rates were much higher than registered rates, residue levels in the plants were below established tolerances.
Isotope Fractionation of 15N and 14N in Microbiological Nitrogen Transformations: a Theoretical Model
Authors: Focht D. D. 
Published: July 2010

AbstractThe kinetics for first‐order multisequence reactions are derived for microbial fractionation of 14N and 15N isotopes. The isotope effect accounts for unreacted substrate becoming progressively enriched in the heavier isotope due to preferential utilization of the lighter isotope by microorganisms. Consequently, during denitrification nitrate becomes enriched in 15N as its concentration diminishes. This inverse proportional relationship is expressed as a hyperbolic function, y = ax−b. Similar curves are derived for nitrate originating from ammonification and/or nitrification. Regression coefficients for a straight line approximation are better than −0.98, but not as good as the actual coefficients for the derived hyperbolic equations. A negative regression “line” for nitrate occurs for all denitrification reactions during isotope discrimination. Nitrate originating from caesin, ammonium, and nitrate are respectively less enriched in 15N for equal nitrate concentration due to ammonium and nitrate being initially enriched in 14N during ammonification and nitrification, respectively.
Removal of Ozone by Soil
Authors: Turner Neil C. , Rich Saul , Waggoner Paul E. 
Published: July 2010

AbstractSimultaneous measurements of the vertical profiles of horizontal wind, temperature, and ozone concentration above a bare, freshly cultivated fine sandy loam were obtained on 12 occasions during a 4‐day period in July when ozone concentrations ranged from 8 to 26 × 1011 molecules (mol) cm−3 (1 × 1011 mol cm−3 = 4 ppb = 8 µg m−3). The decrease in ozone near the soil surface clearly indicated that the soil was removing ozone from the atmosphere. The rate of ozone removal varied from 3 to 12 × 1011 mol cm−2 sec−1. The flux into the soil varied with the concentration of ozone in the air, and indicated a resistance of about 2 sec cm−1 to ozone removal by the soil and the 2.5‐cm air layer immediately above the soil. The rapid removal of ozone by soil in a ventilated chamber suggested a small resistance in the soil alone. A sample of soil containing 14% moisture had a resistance of 0.37 sec cm−1 to ozone removal, which was 0.23 sec cm−1 greater than that of activated charcoal, a strong adsorbing agent. Compaction and additional soil moisture increased the resistance to ozone removal, whereas autoclaving decreased the resistance.
Occurrence of Aflatoxins in Cotton Seeds at Harvest in Relation to Location of Growth and Field Temperatures
Authors: Marsh Paul B. , Simpson Marion E. , Craig Gerald O. , Donoso Julian , Ramey Harmon H. 
Published: July 2010

AbstractCotton seeds (Gossypium hirsutum L.) from 13 locations across the US Cotton Belt in 1969 and 11 locations in 1970 were analyzed for aflatoxins. Samples from most locations did not exhibit detectable aflatoxin contamination. However, aflatoxins B1 and B2 were found in one or more samples collected near Brawley, California; Phoenix, Arizona; and Weslaco, Texas, all in areas where a boll rot caused by Aspergillus flavus Link has been noted repeatedly since the crop of 1953. Aflatoxins occurred especially in seeds whose fiber exhibited a bright greenish yellow (BGY) fluorescence which is diagnostic for this boll rot. When seeds from the 1970 crop were examined for internal fungal infection, A. flavus was detected only in the seeds from Brawley. Free fatty acids were high in seeds from several areas, both with and without accompanying aflatoxins. Weather records indicated that A. flavus boll rot occurs mainly, perhaps exclusively, in conjunction with exceptionally high field temperatures.
The Effect of Fallowing Obtained with Skip‐Row Culture on Verticillium Wilt of Cotton
Authors: Ranney C. D. 
Published: July 2010

AbstractSkip‐row production of cotton (Gossypium hirsutum L.), plant‐4‐rows‐skip‐4‐rows, permits clean fallowing of the nonplanted rows. The fallow obtained from this cultural practice was effective in reducing Verticillium wilt (Verticillium dalhiae Kelb.) incidence, increasing yield, and improving fiber and seed quality. Irrespective of cultivar used during the 2‐year study, cotton produced on plots fallowed for one season produced longer fiber with a higher micronaire reading. Seed quality was also improved in the single test where this variable was evaluated. Following a year of fallow, the onset of Verticillium wilt was delayed, it developed at a slower rate, and total wilt incidence was lower.
The Influence of Soil Arsenic on the Growth of Lowbush Blueberry
Authors: Anastasia Frank B. , Kender Walter J. 
Published: July 2010

AbstractSamples of commercial and virgin soils taken from various lowbush blueberry (Vaccinium angustifolium Ait) areas in Maine contained measurable amounts of As. The highest levels were found in soils from commercial fields which had been repeatedly treated with calcium arsenate for insect control. The amount of As decreased as the soil depth increased. Soils from commercial blueberry fields ranged from 7.7 to 37.8 ppm while virgin soils ranged from 5.7 to 7.0 ppm in the upper levels.Lowbush blueberry plants grown at As levels of 7.7, 17.1, 43.8, 69.5, and 84.5 ppm in a loamy sand in the greenhouse were injured only at the highest level. At 69.5 ppm As and higher blueberry plant growth was significantly inhibited when compared to plants grown at 7.7 ppm As.The greatest As accumulation in blueberry tissue occurred in the roots with decreasing amounts in the stems and leaves, respectively. When foliar As reached 6.7 ppm, a significant reduction in plant growth resulted.Although As was present in all field soils analyzed, at no point did the amount found exceed that which was necessary to produce a reduction in plant growth under greenhouse conditions.
The Role of a Boll Weevil Resistant Cotton in Pest Management Research
Authors: Jenkins Johnie N. , Parrott W. L. , McCarty J. C. 
Published: July 2010

AbstractThe role of the boll weevil (Anthonomus grandis Boh.) resistant cotton (Gossypium hirsutum L.) strain, frego bract, in the management of cotton pests was investigated in 22 fields in Yalobusha County, Mississippi in 1971. The objectives were (i) to measure boll weevil population suppression when frego bract cotton was used with and without a reproduction‐diapause program the previous year, and (ii) to determine if the resistant cotton strain could materially aid in removing the boll weevil as the key pest in cotton fields. If so, one could potentially use integrated control for other cotton pests and also conduct research on pest management systems. The use of the frego cotton suppressed the boll weevil population 69% and 79%. respectively, with and without a diapause program. In addition, the beginning of weekly applications of insecticides for boll weevils was delayed 4 weeks longer in the frego fields than in nonfrego fields. We were able to go through the period of peak activity of the bollworm complex (Heliothis spp.) before we needed boll weevil insecticides in the frego. However, in the nonfrego fields we were applying boll weevil insecticides before and during this time. Thus, frego can be used in research on pest management systems while it continues to be tested for use as a resistance character for commercial varieties.
Tolerance of Escherichia coli to Cadmium
Authors: Zwarun A. A. 
Published: July 2010

AbstractThe effect of Cd on Escherichia coli was studied by measuring the quantity of 14CO2 produced from 14C‐glucose by the organism in the presence of increasing amounts of Cd. The test medium was a simulated fresh‐water source consisting of 0.01% soy peptone in sterile, deionized water (pH 6). Decimal dilutions of Cd, as CdCl2, had no effect on the ability of the organism to produce 14CO2 in concentrations ranging from 0.006 µg Cd/liter to 0.6 mg Cd/liter. At 6 mg Cd/liter a decrease in 14CO2 production was noticed, and a higher concentration of Cd reduced 14CO2 evolution even further. The decrease in 14CO2 evolution by E. coli could be correlated with a decrease in the number of cells surviving the Cd treatments.
Salt Pickup from Agricultural Lands in the Grand Valley of Colorado
Authors: Skogerboe Gaylord V. , Walker Wynn R. 
Published: July 2010

AbstractIntroduction of seepage and deep percolation losses to the saline soils and aquifers, and the eventual return of these flows to the river system with their large salt loads, make the Grand Valley in Colorado one of the more significant salinity sources in the Upper Colorado River Basin. A study was formulated in which the principle components of both the water and salt flow systems were delineated. Water and salt budgets were generated on a monthly basis for the water years 1969–1971.The salt budgets for the 1971 water year have been abstracted from this study and presented herein to illustrate the salt pickup occurring in the Grand Valley area. Results indicate about 51,039 metric tons of dissolved solids being added from the small 1876 ha test area. This salt contribution of about 27.1 metric tons/ha is shown to be proportionate to the valley‐wide pickup. From this analysis, it is concluded that salinity control alternatives must focus on reducing the flow of water in the ground‐water system. Possible measures include conveyance channel linings and improved on‐farm water management practices.
Isotopic Tracer Techniques for Identification of Sources of Nitrate Pollution
Authors: Edwards A. P. 
Published: July 2010

AbstractA comparison was made of the use of natural variations in 15N‐abundance vs. 15N‐enriched and 15N‐depleted fertilizers in determining the contribution of inorganic ammonium fertilizers to the NO3‐N extracted from a Webster soil following a 30C aerobic incubation for 2.5 weeks. The natural abundance approach was unsatisfactory even in this simplified system and its lack of success is shown to be due in part to replicate variability. The fluctuations in 15N‐content of the nitrate from carefully replicated samples of each fertilizer treatment were of the same order of magnitude as the mean difference between the 15N‐contents of natural fertilizer‐N and the soil‐derived NO3‐N. Therefore, the use of labeled fertilizers with 15N‐contents substantially higher or lower than the natural abundance figure is the only valid approach to the measurement of fertilizer contribution to the NO3‐N appearing in tile drains under field condition.
Fate, Metabolism, and Toxicity of 3‐isopropyl‐1H‐2,1,3‐benzothiadiazin‐4(3H)‐1‐2,2‐dioxide in a Model Ecosystem
Authors: Booth Gary M. , Yu Ching‐Chieh , Hansen Dale J. 
Published: July 2010

AbstractBentazon, (3‐isopropyl‐1H‐2,1,3‐benzothiadiazin‐4(3H)‐1‐2,2‐dioxide) a new experimental herbicide, was studied in a model ecosystem. The radioactivity could not be ether extracted from the water until the solution was acidified with HCl. We believe that HCl may be either releasing the parent material from conjugates or that it simply needs acidification before it can be extracted. The major metabolite found in the water was N‐isopropyl anthranilic acid amide, but bentazon was also present in significant amounts. A fresh water crab (Uca minax) contained anthranilic acid, N‐isopropyl anthranilic acid, and bentazon.The aquatic organisms did not accumulate the chemical to any significant degree, although the fresh water crab accumulated it 50 times over the amount found in the water. This was not considered large when compared to DDT.This compound generally does not pose a threat to aquatic food chains on the basis of toxicity nor metabolism results.These data are the first to be published on an experimental herbicide and suggest that the model ecosystem can be used as a tool for routine evaluation of herbicide biodegradability.