bluuebunny/crossref_metadata_2025 huggingface dataset:
The Florida Citrus Industry's Commitment to A Better Environment
Authors: Tucker D. P. H. , Wardowski W. F.
Published: July 2010

This paper discusses the citrus industry's potential role in environmental pollution and steps it is taking to combat any undesirable effects. Where pertinent, grove cultural practices and the fresh fruit packing and processing segments of the industry are analyzed.

The Florida citrus processing industry has made considerable strides in pollution abatement procedures. It is a leader in the utilization of food wastes and has been active in this field since the early 1900's. A striking example of potential pollutants converted to industrial profits is the large number of by‐products now in commercial production and in various stages of research and development.

This recycling plus some use of beneficial insects to control pests, revised fertilization, water usage, heating and processing procedures make the citrus industry of Florida one of the few industries with such a high potential for complete raw product utilization while holding its pollution contribution to acceptable levels.
Municipal Waste Compost: Effects on Crop Yields and Nutrient Content in Greenhouse Pot Experiments
Authors: Terman G. L. , Soileau J. M. , Allen S. E.
Published: July 2010

Five greenhouse pot experiments were conducted to study the utilization or disposal of urban waste compost on agricultural soils. Highly carbonaceous compost applied without additional N induced N deficiency in corn (Zea mays L.) grown on very N‐deficient Mountview sil. This was corrected by applying soluble N. Apparent N deficiency of corn was not induced by compost on soils higher in crop‐available N. Compost supplied considerable N, P, K, Ca, and Zn for corn and tall fescue (Fescue arundinacea Schreb.); P and K in the compost were relatively more available than its content of N. Placing P with compost did not increase availability of the P for corn.

Heavy applications of compost (made from garbage and sewage sludge solids) to soil had a considerable liming effect and increased Zn concentrations and uptake by corn and tall fescue. The liming effect apparently prevented toxicity to corn and snap beans (Phaseolus vulgaris L.) from Zn accumulations from compost on an acid Sango sil.
Municipal Compost: Effects on Crop Yields and Soil Properties
Authors: Mays D. A. , Terman G. L. , Duggan J. C.
Published: July 2010

These field experiments were conducted in connection with the recent upsurge of interest in composting as a disposal method for municipal refuse. Heavy applications of compost made from municipal refuse and sewage sludge were evaluated for production of forage sorghum (Sorghum bicolor L. Moench × Sorghum sudanense P. Stapf.) and common bermudagrass (Cynodon dactylon L.) at Muscle Shoals, Ala., and for corn (Zea mays L.) at Johnson City, Tenn.

Positive yield responses were observed t o annual compost application at rates up to 80 metric tons/ha on bermudagrass, 143 metric tons/ha on sorghum, and 112 metric tons/ha on corn. However, the highest yields of bermudagrass or sorghum attained from compost application were equaled or surpassed by application of fertilizer nitrogen (N) at the rate of 180 kg/ha together with adequate phosphorus (P) and potassium (K). Compost‐induced K deficiency was not observed in any crop.

Incorporation of compost over a 2‐year period significantly increased moisture‐holding capacity and decreased bulk density and compression strength of the soil. The pH, organic matter, K, calcium (Ca), magnesium (Mg), and zinc (Zn) levels were also increased. Soil and plant tissue analyses indicated that potentially toxic amounts of Zn could accumulate in the soil if compost were applied at rates totaling several hundred tons/ha over a few years.
Cadmium Uptake by Plants
Authors: Haghiri F.
Published: July 2010

Absorption of 115mCd by soybean (Glycine max L.) plants via foliar and root systems and translocation into the seed was determined. The uptake of 115mcd by soybeans via the root system was more efficient than that of the foliar placement.

Growth and Cd concentrations of soybean and wheat (Triticum aestivum L.) tops were influenced by soil‐applied Cd. In both crops, the Cd concentration of plant tops increased while yield decreased with increasing levels of applied Cd. Cadmium toxicity began to occur in both crops at the lowest level of soil applied Cd (2.5 ppm). With soybean plants, Cd toxicity symptoms resembled Fe chlorosis. For wheat plants there were no visual symptoms other than the stunted growth.

The relative concentration of Cd found in several vegetable crops varied depending on the plant species. The relative Cd concentration in descending order for various vegetables was lettuce (Lactuca sativa L.) > radish top (Raphanus sativus L.) > celery stalk (Apium graveolens L.) > celery leaves ⩾ green pepper (Capsicum frutescens L.) > radish roots.
Recycling and Recovery of Nitrogen, Phosphorus, and Potassium by Coastal Bermudagrass: II. Under Grazing Conditions with Two Stocking Rates
Authors: Rouquette F. M. , Matocha J. E. , Duble R. L.
Published: July 2010

The effect of two stocking rates on the recycling of N, P, and K was studied for 2 years on a Coastal bermudagrass [Cynodon dactylon (L.) Pers.] sward. Samples for chemical analysis were taken at 14‐day intervals. Available forage, forage yield, and forage consumption were estimated from samples taken at 2‐ to 4‐week intervals. Soil samples were taken prior to, during, and at termination of the grazing trial. Plant nutrient recycling on the high stocked pastures was approximately twice as great during the dry, 1969 season and about 10% higher during the 1970 season compared to that on the low stocked pastures. Recoveries of applied plant nutrients averaged over stocking rates were 84, 50, and 155% for N, P, and K, respectively, during 1969, and 180, 73, and 172% for N, P, and K, respectively, during 1970. There was a substantial soil accumulation of plant nutrients under both stocking rates with a considerable advantage in favor of the high stocked pastures. On the high stocked pastures, total soil N accumulation was slightly less than twofold, available soil P increased threefold, and available soil K increased more than twofold over the 2‐year period.
Enrichment of the Atmosphere with Nitrogen Compounds Volatilized from a Large Dairy Area
Authors: Luebs R. E. , Davis K. R. , Laag A. E.
Published: July 2010

A dairy cow population of 143,000 in an area of 150 km2 enriched the atmosphere with distillable N (mostly NH3) over an area in excess of 560 km2. Over an area of 35 km2, where cow population density was approximately 1,600 cows/km2, the concentration of distillable N in the atmosphere was between 20 to 30 times greater than at a control site outside the dairy area. Highest concentrations of N were associated with wet corral surfaces and favorable evaporative conditions. Approximately 20% of the total N absorbed by acid‐surface traps in the dairy area was nondistillable N while filtered air samples contained 5% or less. Rainfall delivered three times as much N to the land surface inside than outside the dairy area.
Fate of a Mercuric‐Mercurous Chloride Fungicide Added to Turfgrass
Authors: Gilmour J. T. , Miller M. S.
Published: July 2010

The behavior of a mercurous‐mercuric chloride fungicide (Caloclor) added to turfgrass and bare soil was investigated. From 44 to 56% of the total Hg added to a turfgrass surface was lost in 57 days. Plant uptake and removal upon cutting did not account for these losses which were attributed to volatilization of metallic Hg formed in the turfgrass‐soil system. Where additions were made in the turfgrass root zone, loss was reduced and redistribution of Hg in the soil followed a pattern in qualitative agreement with metallic Hg formation and redistribution. Verification of volatilization from bare soil surfaces was made.
Rationale for Optimum Nitrogen Fertilization in Corn Production
Authors: Stanford George
Published: July 2010

During 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

Multiple 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

Heat 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

The 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

A 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

The 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

The 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

Carbofuran 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

The 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

Simultaneous 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

Cotton 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

Skip‐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

Samples 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

The 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

The 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

Introduction 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

A 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

Bentazon, (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.
Experimental and Predicted Movement of Three Herbicides in a Water‐Saturated Soil
Authors: Davidson J. M. , McDougal J. R.
Published: July 2010

The equilibrium adsorption characteristics of 1,1‐dimethyl‐3‐(a,a,a‐trifluoro‐m‐tolyl) urea (fluometuron), 4‐amino‐3,5,6‐trichloropicolinic acid (picloram), and 2,4‐bis(isopropylamino)‐6‐(methylthio)‐s‐triazine (prometryne) on Ca‐saturated Norge loam soil were measured and were found to fit the Freundlich equation. A solution of each herbicide was displaced through a water‐saturated colume of Norge loam soil at various average pore‐water velocities (5.6 to 0.57 cm/hour) and effluent samples evaluated to determine the importance of adsorption kinetics to the mobility of the herbicide. The displacement of each herbicide through the soil was significantly influenced by the average pore‐water velocity. The use of a kinetic adsorption model in a convective transport equation did not adequately predict the shape of the effluent concentration distribution at the high pore‐water velocities, but did give the left‐hand shift exhibited by the data. The tailing noted in all the herbicide effluent concentration distributions resulted primarily from the nonsingularity between the adsorption‐desorption process. Equilibrium adsorption and desorption isotherms were measured for picloram on Ca‐saturated Norge loam soil.
Disposal of Composted Municipal Waste in a Plantation of Young Slash Pine: Effects on Soil and Trees
Authors: Bengtson G. W. , Cornette J. J.
Published: July 2010

A field experiment was conducted to determine the effects of disposal of garbage compost on soil and trees in a 2‐year‐old plantation of slash pine (Pinus elliottii Engelm. var. elliottii) on an excessively drained sandy soil in central Florida. The highly carbonaceous compost was applied at three rates (0, 4.4, and 44 metric tons/ha) in factorial combination with inorganic N fertilizer (0 vs. 224 kg/ha) and with disking vs. no disking following compost application.

At 44 metric tons/ha the compost increased the amount and extended the period of moisture availability to the trees during a drought occurring soon after treatment. Disking (with or without applied compost) also improved soil moisture availability temporarily by reducing weed competition. The compost, particularly at the high rate, decreased soil acidity, and modestly increased soil organic matter, cation exchange capacity, and exchangeable Ca, Mg, and K.

Nitrogen concentration in pine foliage was reduced following application and incorporation of the high rate of compost, but recovery to pretreatment levels was rapid. Concentration of K in foliage was increased by compost application; this effect was persistent.

Height growth of the trees was significantly increased only by disking; this effect diminished in the second year following treatment. No adverse effects of compost on soil or trees were observed, but aesthetics of the site were degraded somewhat by the residue of nondegradable particulates which persisted on the soil surface.
An Analytical Consideration of Undersoil Heating
Authors: Trezek George J. , Obeng Dennis
Published: July 2010

The feasibility of using reject heat from electrical power plants for undersoil heating has been analytically considered. Since soil is a poor thermal conductor, a suitable arrangement of undersoil pipes is required in order to achieve a somewhat uniformly elevated soil temperature. Two‐dimensional steady temperature profiles in soil resulting from a warm water pipe having a wall temperature of 37.8C were computed for several pipe configurations and surface heat transfer coefficients of 1.36 and 136 cal·sec−1·m−2·°C−1. Values of heat transfer on the order of 5 cal·sec−1·m−1 can be obtained. Calculations indicate that in order to apply this technique for the utilization of significant portions of reject heat, the system must be viewed in terms of an agricultural power plant complex encompassing large quantities of land.
Nitrate in Surface and Subsurface Flow from a Small Agricultural Watershed
Authors: Jackson W. A. , Asmussen L. E. , Hauser E. W. , White A. W.
Published: July 2010

A small agricultural watershed on Cowarts loamy sand in the Georgia Coastal Plains was planted in corn (Zea mays L.) each year from 1969 to 1971. Surface and subsurface water samples were collected during each natural rainfall runoff event and NO3‐N was determined.

The initial weighted average NO3‐N concentration was 5 ppm in the subsurface runoff for 3 months before the first planting. The average was 7 ppm in 1969, 10 ppm in 1970, and 9 ppm in 1971. The concentration of NO3‐N in most of the surface runoff for 3 years was less than 1 ppm; the maximum was 3 ppm. Subsurface flow accounted for 80% of the total runoff during the study period. Thus, greater amounts of NO3‐N were discharged in subsurface flow than in surface flow from this watershed.
Inositol Polyphosphates in Activated Sludge
Authors: Cosgrove D. J.
Published: July 2010

Although it is known that some of the soluble inorganic phosphate present in waste water can be fixed as organic forms in the activated sludge process, there is little knowledge of the chemical nature of these products. Recently, the extraction of “inositol phosphate” from activated sludge was described, but whether the product consisted only of myo‐inositol phosphates or was a mixture was not determined. In the present investigation, inositol polyphosphates were extracted from activated sludge using methods previously developed in investigations of soil organic phosphates. Ion exchange chromatography of the purified extract showed it to be a mixture of penta‐ and hexaphosphates of myo‐, chiro‐, scyllo‐ and neo‐inositol and thus to resemble the inositol polyphosphate component of soil organic matter. As the same polyphosphate mixture does not apparently occur in raw sewage (hydrolysates of dried raw sewage were found to contain no other inositol but the myo‐isomer), it would appear that it is formed as a result of biological action during the aeration process.
Nitrogen Transformations and Availability of an Anaerobically Digested Sewage Sludge in Soil
Authors: Ryan J. A. , Keeney D. R. , Walsh L. M.
Published: July 2010

Samples (50 g) of Warsaw sandy loam soil (Typic Argiudoll) were incubated under aerobic conditions with varying levels of an anaerobically digested sewage sludge (up to 1,880 ppm N on an oven‐dry soil basis). Total N, NH4‐N, (NO3+NO2)−N, NH3 volatilization, and hydrolyzable forms of N were determined periodically during 16 weeks of incubation at room temperature (23 ± 3C). At low levels (≤ 235 ppm N), the inorganic N was all converted to (NO3+NO2)‐N while at the higher levels (≥ 940 ppm N), a significant amount of NH4‐N was not nitrified even after 16 weeks of incubation. Recovery of added N was nearly quantitative at the low levels of sewage sludge addition. However, at the higher levels, there was evidence of concurrent nitrification‐denitrification. The hydrolyzable N distribution results indicated that very little of the hydrolyzable N was mineralized at the low rates of application. At the high rates of application, apparent development of anaerobic conditions led to more rapid mineralization of the sewage sludge organic N than was found under aerobic conditions. The data indicate that from 4 to 48% of the organic N in the sewage sludge was mineralized to (NO3+NO2)−N in 16 weeks. Thus, the availability of sewage sludge organic N must be considered when evaluating the potential of the material as a fertilizer or a possible source of NO3‐N to ground waters.
Fluoride Accumulation by Forage: Continuous vs. Intermittent Exposures to Hydrogen Fluoride
Authors: MacLean D. C. , Schneider R. E.
Published: July 2010

The pattern of fumigation with gaseous HF markedly affects the rate and amount of F accumulated by timothy (Phleum pratense L.) and red clover (Trifolium pratense L.) plants. F accumulation was greater after continuous fumigations than when the same HF dose was provided in alternate 48‐hour exposures. The importance of the intermittent nature of exposures in addition to the pollutant concentration and duration of exposure in governing F accumulation suggests that pollution abatement action to protect livestock from ingested F should be based on the F content of forage rather than the concentration of airborne fluorides.
Phosphorus Relationships in Runoff from Fertilized Soils
Authors: Römkens M. J. M. , Nelson D. W.
Published: July 2010

The effect of P fertilizer mixed into soil on the P composition of runoff was studied. Runoff samples from artificial rainstorms on fallow plots of Russell sil soil, and P enriched soil‐water mixtures (1:50) of Russell sil and selected other soils were analyzed for water soluble orthophosphate and extractable, total, and organic P in sediment. The relation of P addition rate to the soluble orthophosphate or sediment extractable phosphorus level in runoff was approximately linear. The relation of soluble orthophosphate to extractable P in soil‐water systems was linear for most soils studied. Soluble orthophosphate and extractable P in sediment were not related to total P or to organic P in sediment. A procedure was suggested for estimating the soluble orthophosphate concentration in runoff from fertilized wet soil using laboratory analyses.
Loss of Mercury(II) from Solution
Authors: Newton D. W. , Ellis Roscoe
Published: July 2010

Loss of mercury(II) from dilute solutions was studied using 203Hg(II) as a tracer. Magnitude and rate of loss depend on Hg(II) concentration, chemical composition of carrier solutions, and container material. Losses were severe only at Hg(II) concentrations of 10−6M (0.2 ppm) or lower. Of the Hg‐containing solutions studied, loss was greatest from 0.01M CaCl2; Hg(II) was stable at all levels in concentrated HNO3. Increasing pH from 4 to 8 appeared to reduce Hg loss. Adding KMnO4 also reduced losses. Glass and plastic containers differ in their ability to retain Hg(II) in solution. The problem of Hg loss has serious implications in analyses of Hg as an environmental contaminant and in research where low concentrations of Hg are used.
Fate of Mirex‐14C During and After a 28‐Day Feeding Period to a Lactating Cow
Authors: Dorough H. Wyman , Ivie G. Wayne
Published: July 2010

The use of mirex [1,3,4‐methenododecachlorooctahydro‐2H‐cyclobuta (c,d) pentalene] for the control of the imported fire ant in pasture land is a potential source of contamination of meat and milk of dairy animals. To determine the level and nature of the residues which might occur should the animals consume the insecticide in the diet, mirex‐14C was administered via gelatin capsules twice daily to a lactating Jersey cow for 28 days. The daily dose was equivalent to approximately 0.2 ppm mirex in the diet. Radioactive residues in the feces reached a maximum of 50% of the consumed dose after 3 weeks and remained at that level until treatment was terminated. An additional 3% was eliminated in the feces during the 28‐day post‐treatment period. Mirex‐14C equivalents in the milk reached an equilibrium after about 1 week of treatment. Approximately 10% of the administered doses were eliminated daily by this route with the concentration in the whole milk after equilibration being 0.058 ppm. One week after removing the mirex source, the residues in the milk dropped to 0.006 ppm and then declined gradually to 0.002 ppm after 28 days. Residue levels in the tissues 28 days after the final treatment were: fat, 0.21 ppm; liver, 0.03 ppm; and kidney, 0.02 ppm; the muscle and brain contained no detectable residues. TLC (thin‐layer chromatography) and GLC (gas‐liquid chromatography) analyses of the milk, feces, and fat demonstrated that unchanged mirex‐14C was the only radioactive component of these substrates.
Effect of Beef‐Feedlot‐Lagoon Water on Soil Chemical Properties and Growth and Composition of Corn Forage
Authors: Wallingford G. W. , Murphy L. S. , Powers W. L. , Manges H. L.
Published: July 2010

Land disposal of beef‐feedlot‐lagoon (runoff) water was studied. Rates of 0, 8, 15, 26, and 46 cm/year of lagoon water were applied during the summers of 1970 and 1971 by furrow irrigation to a silty clay loam soil. Corn (Zea mays L.) forage yield and plant content of N, P, K, Ca, Mg, and Na were measured. Surface soil samples and soil cores were taken from the plots after harvest each year.

Electrical conductivity ranged from 1.6 to 7.6 (3.1 average) mmho/cm in the lagoon water applied at the study site and from 1.0 to 12.8 mmho/cm in samples taken from 12 Kansas feedlots. Electrical conductivities of extracts from saturated pastes of the surface soil samples were increased linearly by accumulative treatment both years. The 1970 and 1971 soil cores showed accumulations of NO3−‐N, P, K, and Na in the top 30 cm at all treatment rates. Movement of NO3−‐N and Na down to 100 cm was noted in the 1971 cores from plots receiving 46 cm/year. Ca and Mg in the soil cores were not affected by treatment either year. Corn forage yields were a linear function of treatment in 1970 and a quadratic function in 1971. The positive effect on yield both years was attributed to increased soil fertility; the relative decrease in 1971 at the 26 and 46 cm/year rates was attributed to increased soil salinity. Maximum yield and uptake of N and P were reached at the 15 cm/year disposal rate in 1971.
Transformations of Methylamines and Formation of a Hazardous Product, Dimethylnitrosamine, in Samples of Treated Sewage and Lake Water
Authors: Ayanaba A. , Alexander M.
Published: July 2010

Added trimethylamine is converted to dimethylamine in samples of raw sewage and lake water, and the secondary amine thus formed or added dimethylamine disappears with time. The rates of formation and disappearance of dimethylamine are governed by the pH and the type and amount of inorganic N present. Ammonium is generated from both of the amines. Dimethylnitrosamine, a potent carcinogen, is formed in small amounts in samples of sewage and lake water receiving dimethylamine and nitrite, the maximum nitrosamine level detected rising with increasing acidity and increasing dimethylamine and nitrite concentrations. Dimethylnitrosamine also appears in sewage and lake water samples receiving trimethylamine. Microorganisms are involved in some stage of the conversion of the tertiary amine to the secondary amine and dimethylnitrosamine in sewage because these products are not found in sterilized sewage. The fungicide thiram (tetramethylthiuram disulfide) is converted to dimethylamine in sterilized sewage at pH 4.0, and small amounts of dimethylnitrosamine are also produced in the presence of nitrite; the yields of both products are far greater in nonsterile, thiram‐amended sewage. The identification of dimethylnitrosamine was verified by thin‐layer and gas chromatography, ultraviolet and infrared spectrometry, and combined gas chromatrophy‐mass spectrometry.
Methylmercury Formation in Mercury‐Treated River Sediments During in situ Equilibration
Authors: Jacobs L. W. , Keeney D. R.
Published: July 2010

An in situ experiment was established at two environmentally different river sites (one each on the Wisconsin and Fox rivers) to evaluate the extent of methylmercury (MeHg) production in and Hg loss from sediments treated with mercuric chloride (HgCl2) or phenylmercuric acetate (PhHgAc). Bulk sediment was collected from each river site, treated with approximately 1, 10, or 100 ppm Hg (oven‐dry basis) as HgCl2 or PhHgAc, and returned to the river site with untreated controls for 2, 4, or 12 weeks of equilibration with the aquatic environment. After each sample retrieval, the sediments were analyzed for total Hg using an aqua regia digest and flameless atomic absorption spectrophotometry and for MeHg by gas chromatography using a modified extraction procedure which is described.

Results suggest that Hg losses from stationary sediments are minimal and that sediment transport is probably the major source of Hg movement in a river system. In both sediments, more MeHg was produced from PhHgAc than from a similar concentration of HgCl2, and MeHg concentration increased as the Hg treatment with either compound was increased. The MeHg concentrations found in the Wisconsin River sediments were substantially higher than in the Fox River sediments with a similar Hg treatment. The large differences in MeHg production between these two sediments may be partially attributed to their chemical dissimilarities. The Wisconsin River sediment is acidic and contains more organic materials compared to the Fox River sediment which is more alkaline and contains larger amounts of sulfide sulfur.