bluuebunny/crossref_metadata_2025 huggingface dataset:
Phosphorus Removal from Static Sewage Effluent Using Duckweed
Authors: Sutton David L. , Ornes W. Harold
Published: July 2010

Dry weights of a mixed population of duckweed (Lemna gibba L. and Lemna minor L.) grown for 2 weeks in 12 liters of 6, 12, and 25% concentrations of secondary treated sewage effluent were 16, 23, and 31% higher, respectively, than plants grown in pond water. Concentrations of sewage effluent > 25% did not increase dry weight production. A maximum yield of 28 g dry weight/m2 was estimated for 7 days beginning with the second week of an 8‐week period by removing weekly one‐half of the duckweed from containers filled with 760 liters of 100% sewage effluent held under static conditions. Yield dropped to 4.6 g/m2 during the last 7 days of the 8‐week growing period. A 97% decrease in orthophosphate phosphorus (P) in the sewage effluent occurred during this time. Phosphorus content of duckweed was directly related to the P content in the sewage effluent up to a concentration of 2.1 µg/ml. Crude protein content of duckweed tissue removed from solutions containing 50 and 100% sewage effluent was almost three times that of plants grown in the pond water. Duckweed harvested 1 week after being planted in the containers filled with 100% sewage effluent under static conditions contained almost four times the crude protein as compared to plants harvested at the end of the 8‐week growing period.
Movement of Methylene Blue Active Substances from Septic Tank Effluent through Two Coastal Plain Soils
Authors: Reneau R. B. , Pettry D. E.
Published: July 2010

Methylene blue active substances (MBAS) concentration as a function of distance and depth in soils with high perched water tables were monitored as part of a study, supported by the Virginia Department of Health, to determine movement of septic pollutants through natural soil systems. The soils studied were Varina and Goldsboro. Piezometers were placed at selected distances and depths from the drainfield in the direction of ground‐water flow to determine both vertical and lateral movement. Also, soil adsorption studies were conducted on selected horizons from these soils to determine the influence of adsorption on distance traveled and biodegradation. Horizontal movement of MBAS in both soils were generally limited to 3.0 m or less. In the Varina, decreases in MBAS above the plinthic horizon could be described adequately as a semilogarithmic function. MBAS in this zone decreased from 0.80 and 0.51 to 0.49 and 0.29 mg/liter from 0.15 to 3.0 m from the drainfield for the winter and summer seasons, respectively. At the 6.1 m distance, concentrations were reduced to 0.10 and 0.12 mg/liter, respectively. In the plinthic horizon, MBAS concentrations were greater adjacent to the drainfield, but decreased more rapidly with distance. The decrease in MBAS in this horizon could be described by a logarithmic function.

At the Goldsboro location, MBAS was concentrated at the 152 cm depth sampled for both the winter and summer seasons. During the winter, concentrations at the 152 cm depth remained at approximately 0.50 mg/liter through 1.5 m distance then decreased significantly. During the summer MBAS concentrations were approximately three times higher and extended to the 3.0 m distance before decreasing significantly. There was no indication of movement of MBAS at the 432 cm depth in this soil.

Soil adsorption studies indicated that these soils were capable of adsorbing large quantities of linear alkylbenzenesulfonate (LAS), but inefficiently under saturated conditions as indicated by adsorption of approximately 65% of the original for all three levels employed.
Effects of Waterhyacinth Cover on Water Chemistry, Phytoplankton, and Fish in Ponds
Authors: McVea Charles , Boyd Claude E.
Published: July 2010

Waterhyacinth [Eichhornia crassipes (Mort.) Solms] cover of 0, 5, 10, or 25% surface was established in fertilized ponds stocked with the fish, Tilapia aurea (Steindachner), at Auburn, Alabama. Measurements of water chemistry, phytoplankton density, and fish production were made during the 1973 growing season.

Phytoplankton production was less in ponds with 10 and 25% cover by waterhyacinth than in ponds with 0 and 5% cover. Competition of waterhyacinth with phytoplankton involved shading and removal of phosphorus from the water.

Concentrations of dissolved oxygen were lowest in ponds with 25% cover, but oxygen tensions in all ponds were adequate for survival and growth of fish.

Reduction in phytoplankton growth in ponds with 10 and 25% cover resulted in much lower fish production. The presence of 5% cover by waterhyacinth did not significantly affect fish production.
Effect of Municipal Wastes on Crop Yields and Uptake of Heavy Metals
Authors: Giordano P. M. , Mortvedt J. J. , Mays D. A.
Published: July 2010

A field experiment was initiated in fall 1971 to compare 90‐, 180‐, and 360‐kg/ha rates of Zn supplied in ZnSO4 and in garbage compost or sewage sludge. The same treatments were reapplied to half of each plot in fall 1972. Forage yields of sweet corn (Zea mays L.) in 1972 and 1973 were higher with applied compost and sludge but were unaffected or reduced by ZnSO4 applications. Concentrations of Zn were much higher in forage with ZnSO4 than with the organic wastes; concentrations in grain were similar among all treatments. Reapplication of the treatments did not result in proportional increases in heavy metal concentrations in either forage or grain. However, concentrations of Cd in forage and grain were about threefold higher with compost and sludge.

Bush beans (Phaseolus vulgaris), double‐cropped after sweet corn each year, were more sensitive to excessive Zn. All rates of ZnSO4 and sewage sludge depressed yields of mature pods, and dry matter yields of bean vines were lower with the high rate of ZnSO4 but relatively unaffected by sludge. Concentrations of Cd and Ni were slightly higher in vines and pods from sludge‐treated plots.
Losses of Diuron, Linuron, Fenac, and Trifluralin in Surface Drainage Water
Authors: Willis G. H. , Rogers R. L. , Southwick L. M.
Published: July 2010

Diruon [3‐(3,4‐dichlorophenyl)‐1,1‐dimethylurea], linuron [3‐(3,4‐dichlorophenyl)‐1‐methoxy‐1‐methylurea], fenac [(2,3,6‐trichlorophenyl)acetic acid], and trifluralin (α,α,α‐trifluoro‐2,6‐dinitro‐ N,N‐dipropyl‐p‐toluidine) were applied to plots designed for sampling surface runoff. Over a 3‐year period, highest concentrations in runoff were usually associated with rainstorms that occurred soon after application. Maximum seasonal losses were < 0.12, 0.30, 2.90, and 0.05% of the applied diuron, linuron, fenac, and trifluralin, respectively. The data suggest that with proper use on agricultural land in the lower Mississippi River Valley these herbicides pose little threat to adjacent aquatic areas.
Nitrate, Phosphorus, and Sulfate in Subsurface Drainage Water
Authors: Baker J. L. , Campbell K. L. , Johnson H. P. , Hanway J. J.
Published: July 2010

Measurements made over a 4‐year study of flow and NO3‐N, PO4‐P, total P, and SO4‐S content of subsurface drainage water from tile‐drained cropland indicate that annual nutrient losses are highly variable. Annual losses of phosphorus, SO4‐S, and NO3‐N ranged from 0 to 0.04, 0 to 32, and 0 to 93 kg/ha, respectively, being very dependent on the amount of water lost. Because of low concentrations of phosphorus, losses with subsurface drainage water were insignificant when compared with losses associated with surface runoff. Concentrations of SO4‐S and NO3‐N were seemingly inversely related. Tile drainage water with consistently high NO3‐N content relative to surface runoff (> 10 ppm even under the low‐fertility management of this study, 224 kg/ha of N over 5 years) is believed responsible for the high NO3‐N content sometimes found in a river draining central Iowa. The nitrate content of water from the saturated and unsaturated zones of the soil profile indicates that waves or pulses of water, with different NO3‐N concentrations, moving through the soil profile cause the observed variation of NO3‐N content of subsurface drainage water with time and flow rate. Such variations illustrate the difficulty of identifying water‐quality trends from limited data.
The Time Stability of Dissolved Mercury in Water Samples—I. Literature Review
Authors: Jenne E. A. , Avotins Peter
Published: July 2010

Conflicts in the published findings of adequacy of various preservation treatments for water samples intended for mercury analysis are common and appear to result from variations in (i) biological effects; (ii) initial concentrations of mercury; (iii) types of containers used; (iv) properties of the water or laboratory solution (particularly, the dissolved organic and reduced metal cation content); (v) duration of experiments; (vi) concentration of preservative; (vii) analysis, whether conducted in the original storage container or aliquots taken to another vessel; and (viii) the definition of adequacy employed. Of these variables, the biological effects have been overlooked by most investigators.
Yield and Metal Composition of Corn and Rye Grown on Sewage Sludge‐Amended Soil
Authors: Cunningham J. D. , Keeney D. R. , Ryan J. A.
Published: July 2010

A greenhouse experiment is reported which was designed to evaluate possible detrimental effects due to high loadings of waste water sludge from four Wisconsin municipalities. The sludges were selected because of abnormally high concentrations of Zn, Cu, Cr, or Ni, and were mixed, after being air‐dried, with a limed (pH 6.8) sandy loam soil at rates from 63 to 502 metric tons/ha (oven‐dry solids basis). The soils then were leached to remove soluble salts. Three crops [corn (Zea mays L.), rye (Seceale cereale L.), and corn] were then grown in succession on the sludge‐amended soils. Soil solution conductivity and soil pH were monitored at each cropping, and vegetative yield and tissue concentration of Cd, Cr, Cu, Mn, Ni, and Zn determined.

One of the sludges was a high lime (pH 7.8) material, and this sludge raised soil pH to 7.4. At the high rates, the other sludges lowered pH somewhat. Also, soluble salts reached sufficient concentration at the higher rates to be detrimental to yield of the first corn crop. Significant positive yield responses, due to N, P, and K added by the sludges, occurred up to the 125 metric ton/ha rate. On all but the high pH sludge, crop yields were depressed at the high rate. The tissue concentration of metals increased with sludge rate, and significant differences between sludges were found with respect to tissue metal concentrations. Phytotoxic concentrations of Cu occurred most often. On the average, the tissue concentrations of the control were Cd, 0.4; Cr, 1.4; Cu, 7.4; Mn, 33; Ni, 1.7; and Zn, 38 ppm whereas at the 502 metric ton/ha rate of sewage sludge the values were Cd, 5; Cr, 6; Cu, 23; Mn, 346; Ni, 16; and Zn, 289 ppm.
Migration of Salt from Feedlot Waste as Affected by Moisture Regime and Aggregate Size
Authors: Amoozegar‐Fard A. , Fuller W. H. , Warrick A. W.
Published: July 2010

The migration of salt from three different aggregate sizes of feedlot manure under three moisture regimes was evaluated. The three sizes were small (to pass a 40‐mesh sieve), medium (0.9 cm in diameter, 2.25 cm in length), and large (4.8 cm in diameter, 2.6 cm in length). The three moisture regimes were: (i) 12 hours saturation, 12 hours drainage by gravity, this step was repeated five times; (ii) 12 hours saturation, 12 hours drainage by gravity, 48 hours oven drying at 60C, also repeated five times; and (iii) continuous leaching for 60 hours at a constant rate. After each 12‐ hour saturation period the leachates were collected and the electrical conductivity (EC), pH, and concentrations of K, Na, Ca, Mg, NH4, NO3, Cl, S, P, and eight trace elements determined.

The EC of the leachate for the first saturation period was highest for the small‐sized aggregates under all three moisture regimes (21.3, 21.2, and 19.3 mmhos/cm, respectively) and the lowest for the large‐sized aggregates under continuous leaching (8.3 mmhos/cm). During the later leaching periods, the EC of the leachate for the large aggregates was higher than the other two sizes. Continuous leaching resulted in a lower EC for the first and a greater EC for the later saturation periods compared to the other two treatments. As for the individual salts, the migration pattern for K, Na, S, and Cl was similar to that for EC, however, the pattern for the other ions was dissimilar.
Uptake of Cadmium—Its Toxicity, and Effect on the Iron Ratio in Hydroponically Grown Corn
Authors: Root Robert A. , Miller Raymond J. , Koeppe D. E.
Published: July 2010

The uptake of cadmium by corn roots (Zea mays L.) and shoots from hydroponic solutions was determined over time intervals from 3–12 days. This uptake from solutions containing 1–40 mg cadmium/liter of solution was correlated with leaf chlorophyll content, dry matter production, and tissue concentration of zinc and iron. Cadmium concentration in roots and shoots increased with increased time of treatment. Roots of plants treated for 12 days contained about twice the cadmium found in shoots (approximately 200–1,100 µg cadmium/g dry weight in roots and approximately 100–450 µg cadmium/g dry weight in leaves). The dry weight of both roots and shoots, and of leaf chlorophyll concentration, decreased with increased cadmium tissue concentrations. The zinc concentration decreased, but the iron concentration increased, in leaves and roots as the cadmium concentration increased. These data resulted in a linear relationship between the increase of tissue cadmium and the increasing iron/zinc ratio. While the chlorosis of cadmium‐treated leaves appeared to be comparable to that resulting from iron deficiency, the data presented indicate that an iron deficiency is not the cause of leaf chlorosis in cadmium‐treated plants. A more important factor in cadmium toxicity may be the apparent correlation between an increase in tissue cadmium concentrations and the corresponding increase in the iron/zinc ratio.
Deposition of Airborne Particulates onto Plant Leaves
Authors: Klepper Betty , Craig D. K.
Published: July 2010

In order to assess potential environmental hazards from foliar absorption of airborne pollutants released in stack effluents from industrial plants, it is necessary to measure deposition characteristics onto plant foliage. This paper describes an exposure chamber which permits highly toxic materials to be delivered to plant leaves under reproducible conditions of wind speed and aerosol concentration. An aerosol of a gold colloid labelled with 198Au and having an activity median aerodynamic diameter (AMAD) of about 0.8 µm was used in experiments with bean leaves (Phaseolus vulgaris L. var. ‘Tendergreen’) and with inert surfaces. Measurements were made of leaf area, wind speed, and aerosol concentration and particle size distribution. Leaves oriented toward and away from winds of 0.42 cm/second showed similar deposition rates for particles with an AMAD of about 0.8 µm. Deposition velocities for leaves were similar to deposition velocities measured for upward facing inert surfaces which were an order of magnitude greater than downward facing inert surfaces for the aerosols and wind velocities used in these experiments.
The Time Stability of Dissolved Mercury in Water Samples‐II. Chemical Stabilization
Authors: Avotins Peter , Jenne E. A.
Published: July 2010

Bacteria were found to be the principal cause of instability of mercury in laboratory solutions. The volatilization loss rate increased rapidly after a variable lag period and then leveled off with increasing time. The marked reduction in the loss rate of mercury is a result of its combination with bacterial cells and metabolites. Reagents which either oxidize or solubilize organics removed mercury most effectively from sample containers in which mercury‐bearing water had been stored. A small amount of mercury was found to have diffused into the polyethylene bottles. Solute mercury was most effectively stabilized in laboratory solutions and water samples with 0.05% KMnO4 without acidification.
Eutrophication of Microponds
Authors: Batchelder A. R.
Published: July 2010

Three soils having different chemical and physical properties were flooded with deionized water and used as bottom soils for greenhouse microponds. The submerged soils supplied sufficient nutrients to the overlying waters to sustain algal growth for 489 days in two successive floodings of 219 and 270 days each.

Differences in electrical conductivity, pH, and nutrient concentration were observed among the three soils and a control nutrient solution. During the first flooding, indigenous algae prevailed in the soil systems, but during the second flooding the dominant algal genera were less diversified.

In a companion study, in which perennial ryegrass (Lolium perenne L.) was grown in the same three soils, the grass yields per kilogram of soil could not be related to the ash‐free biomass yields per kilogram of soil in the microponds. Algal growth could not be predicted from soil characteristics or solution composition, or the productivity of cropped soils, but the study showed that submerged soils can be a sole source of algal nutrients.
Influence of Pesticides on Denitrification in Soil and with an Isolated Bacterium
Authors: Bollag Jean‐Marc , Henninger Nancy M.
Published: July 2010

Various pesticides were tested for their influence on the denitrification process in soil and on an isolated denitrifying bacterium. In soil the denitrifying activity was essentially inhibited by the fungicides captan (N‐trichloromethylmercapto‐4‐cyclohexene‐1,2‐dicarboximide), maneb (manganous ethylenebisdithiocarbamate), and nabam (disodium ethylene‐1,2‐bisdithiocarbamate), and to a lesser extent by the herbicide 2,4‐D (2,4‐dichlorophenoxy‐acetic acid). In pure culture studies with a bacterium whose end product in denitrification was nitrous oxide, the fungicides also caused strong inhibition of the respiratory nitrate reduction process; the insecticide carbaryl (1‐naphthyl N‐methylcarbamate), the phenylurea herbicides, 2,4‐D and propham (isopropyl carbanilate) also functioned as inhibitors, but to a lesser extent. It was of special interest to observe that the inhibition by certain pesticides influenced the formation rate of nitrite and sometimes prevented the reduction of accumulated nitrite during incubation under anaerobic conditions.
Retention of Metals in Sewage Sludge II: Incorporated Radioisotopes
Authors: Lagerwerff J. V. , Biersdorf G. T. , Brower D. L.
Published: July 2010

Samples of digested sewage sludge from Baltimore, Md. and Washington, D.C. were columned and leached for up to 240 hours with 0.06N CaCl2, as well as with water, to study the release of trace amounts of 85Sr and 137Cs introduced earlier. In percent of the radioactivity originally present, leaching with 0.06N CaCl2 removed about 90 and 80% of 85Sr, but about 9 and 16% of 137Cs from Baltimore and Washington, D.C. sludge, respectively. For leaching with H2O, the corresponding values were 39 and 34% of 85Sr and 4 and 3% of 137Cs.

Samples of sludge were subjected to treatments with H2O2, and steambath drying, followed by incubating with 137Cs and 85Sr, and either exhaustive leaching with H2O (240 hours at 2 cm3 cm−2 hour−1), or equilibration for 1 hour with H2O or 0.01N HCl. In percent of the radioactivity originally present, the pretreatment increased 137Cs release by H2O leaching from 9 to 18%, and from 7 to 10% with Baltimore and Washington, D.C. sludge, respectively, depending on whether the sludge was pretreated with H2O or with 3% H2O2. Corresponding ranges for 85Sr were from 47 to 55% and from 41 to 48%.

Incubation of Baltimore and Washington sludge for 44 months at room temperature slightly increased H2O extractability of 137Cs and 85Sr when the incubated material was kept dry, rather than moist. This may have been due to smaller concentrations of complexing organic compounds, or to compounds with lesser complexing ability. When sludge was stored moist, the 0.01N HCl extractability of the isotopes sharply increased. This would also point to a greater abundance of organic complexes under moist conditions during storage, since a decrease in pH affects their stability.
The Influence of Applied Phosphorus, Manure, or Lime on Uptake of Lead from Soil
Authors: Zimdahl R. L. , Foster J. M.
Published: July 2010

Studies of the uptake of lead from soil by corn (Zea mays L.) have shown that soil applications of phosphorus [Ca(H2PO4)2·H2O] decrease uptake, but translocation was affected and at higher lead levels. Lead uptake decreased when cow manure was added to attain a total organic content of 6%, but there was no effect of additional manure. Liming did not have a consistent effect on uptake, but lead translocation appeared to decrease with liming. The addition of phosphorus was not an agronomically feasible way to reduce the effects of lead contamination, but additions of manure and lime offered promise of reducing lead uptake.
Photochemical Oxidants in Yonkers, New York: Effects on Yield of Bean and Tomato
Authors: MacLean D. C. , Schneider R. E.
Published: July 2010

Field plots of bean (Phaseolus vulgaris L. cv. Tendergreen) and tomato (Lycopersicon esculentum Mill. cv. Fireball 861 VR) were enclosed in chambers and exposed for 43 or 99 days, respectively, to ambient air or to air from which 60 to 70% of the ambient photochemical oxidants were excluded. Comparisons between these treatments revealed that ambient oxidants at Yonkers, New York reduced the fresh weight yield of tomato by at least 33%, and in bean, the weight and number of marketable pods were reduced by 26 and 24%, respectively.
Soil Nitrates Following Four Years Continuous Corn and as Surveyed in Irrigated Farm Fields of Central and Eastern Colorado
Authors: Ludwick A. E. , Reuss J. O. , Langin E. J.
Published: July 2010

High rates of fertilizer N used in many intensive farm management systems have been cited as a potential pollution hazard to surface and ground waters. The purpose of this study was to evaluate soil NO3− accumulations following 4 years continuous corn (Zea mays L.) grown with different nitrogen and irrigation regimes, and to compare these results to present NO3− concentrations found in irrigated farm fields of central and eastern Colorado.

Soil NO3− content in the 300‐cm sampled profile was significantly influenced by both fertilizer N and irrigation treatments; the greater accumulations were associated with the two higher fertilizer N rates and two lower irrigation rates. Nitrate increased linearly in relation to fertilizer N between 67 and 269 kg N/ha and could be described by two simple regression equations separating the irrigation treatments into two groups (l‐2 and l‐3, low rates; l‐4 and l‐5, high rates). Coefficients of determination for the two groups were 0.981 and 0.975, respectively.

Two hundred and seventy irrigated farm fields were sampled to a depth of 90 cm in central and eastern Colorado. Mean soil NO3−‐N content was 173 kg/ha and contents were not significantly different between coarse and fine textured groupings. Fields sampled immediately following beans (Phaseolus vulgaris L.) contained similar amounts as those following corn. Mean soil NO3− content decreased with greater soil depth.

Observed NO3− concentrations appear to be the result of gradual accumulations from annual or near‐annual fertilizer N and/or manure applied over a period of time. Data from the 4‐year corn experiment clearly illustrate that NO3− can accumulate in a soil profile even when fertilizer N is applied at rates below that required for maximum production.
Effect of Snowmobile Traffic on Bluegrass (Poa pratensis)
Authors: Foresman C. L. , Ryerson D. K. , Walejko R. N. , Paulson W. H. , Pendleton J. W.
Published: July 2010

Varying snowmobile traffic was imposed on established bluegrass (Poa pratensis) areas at Arlington and Lancaster, Wisconsin for three winters. The effect on the stands, recovery, and vigor the following summer was monitored by close observations and the yield of frequent clippings.

No reduction in bluegrass stands occurred following snowmobiling. Early spring recovery and growth was slower in snowmobile track areas than in nontract areas. However, by early summer, traffic and nontraffic areas showed no differences in vigor, color, or growth as measured by clipping weights. Soil bulk density determinations did not differ between snowmobile track and nontrack areas.
Effects of Sulfur Dioxide on Pinus resinosa Seedlings in the Cotyledon Stage
Authors: Constantinidou H. , Kozlowski T. T. , Jensen K.
Published: July 2010

Seedlings of red pine (Pinus resinosa Ait.) in the cotyledon stage of development were exposed to four concentrations of SO2 (0.5, 1, 3, or 4 ppm) at four exposure times (15, 30, 60, or 120 minutes). Seedling development was inhibited by SO2 at all concentrations for 120 minutes and at 1.0 ppm and above for 30 minutes or longer. The adverse effects were proportional to SO2 concentration and duration of exposure. The fumigations induced chlorosis in both cotyledons and primary needles, slowed expansion of primary needles, inhibited dry weight increment of both cotyledons and primary needles, and induced necrosis of tips of cotyledons and primary needles. Growth of seedlings was inhibited more by increasing the duration of exposure to SO2 than by increasing SO2 concentration. The extreme sensitivity to SO2 of pine seedlings in the cotyledon stage suggests that their exposure to continuous fumigation in the field, even at low dosages, may adversely influence seedling development and regeneration of pine communities.
Picloram Degradation in Soils as Influenced by Soil Water Content and Temperature
Authors: Guenzi W. D. , Beard W. E.
Published: July 2010

A laboratory experiment was designed to determine the effect of temperature and alternating incubations at field capacity and during drying periods on the degradation of picloram (4‐amino‐3,5,6‐trichloropicolinic acid) in five soils. Picloram was added at a rate of 10 ppm, and degradation was measured by 14CO2 evolution resulting from the cleavage of the labeled carboxyl carbon. Picloram degraded very little at 5C and increased only slightly up to 25C. Three soils were highest in degradation rates at 30C while two soils were highest at 50C. Picloram degradation rates during 20‐day incubation periods at field capacity, interrupted with 16‐day drying cycles, varied among soils and decreased after each successive drying cycle at 30 and 50C, except for one soil at 50C. The degradation rate decreased gradually as water content decreased from field capacity (≃0.33 bar) to 15 bars tension, and ceased after the soils were air dried.
Effect of Spray Irrigation with Municipal Sewage Effluent on the Cereal Leaf Beetle and the Frit Fly Infesting Reed Canarygrass
Authors: Byers R. A. , Zeiders K. E.
Published: July 2010

Twelve clones of reed canarygrass (Phalaris arundinacea L.) that were spray irrigated with municipal sewage effluent had a mean of 0.03 larva per clone of cereal leaf beetle (Oulema melanopus L.) on 7 June 1974; similar unirrigated clones had a mean of 3.2 larvae per clone on that date. Also, the irrigated clones had fewer culms killed by the frit fly (Oscinella frit L.) than unirrigated clones on 7 June and 12 Aug. 1974. Therefore, reed canarygrass as a receptor of sewage effluent, already the most acceptable species because of its flood tolerance, is even more desirable because there should be fewer numbers of these two important pests.
Nitrogen Balance in the Southern San Joaquin Valley
Authors: Miller Robert J. , Smith Richard B.
Published: July 2010

A nitrogen balance for the southern San Joaquin Valley of California has been calculated, using techniques and methodology developed for the Upper Santa Ana River Basin of southern California. The two areas differed considerably in both size (the latter being much smaller) and agricultural function. Data were compiled on N inputs, use, and outputs for many sources within the study area. Such data enabled construction of a flow diagram depicting best estimates of N pools and fluxes within the San Joaquin Valley basin. Results show N inputs into the study area from various sources were somewhat greater than output to the atmosphere and by plant removal. Inputs to the soil N pool were about 9 kg/ha more in 1971 than in 1961. Since the soil N pool was estimated to be about 11 metric tons/ha, this represented an increase of about 0.1%. However, since the increases of N are not evenly distributed over the study area, high N concentrations can develop in some local areas.
Chemical Changes in the Soil Solution from a Spodosol Irrigated with Secondary‐treated Sewage Effluent
Authors: Hortenstine C. C.
Published: July 2010

The native vegetation (Pinus elliotti, P. palustris, Quercus geminata, Serenoa repens, Aristida stricta, etc.) on 40 ha of Spodosols at Walt Disney World, near Orlando, Fla., was chopped and turned under in the winter of 1972. The following summer, three tree species (Eucalyptus robusta, Liquidambar styraciflua, Platanus occidentalis) and one grass species (Cynodon dactylon) were planted. Irrigation with secondary‐treated sewage effluent at 5 cm/week was initiated in July 1972 in an attempt to determine the renovative capability of Spodosols. The soil solution was monitored chemically by drawing samples through porous ceramic cups placed at 60‐, 90‐, and 120‐cm depths in the soil profile. Phosphorus content increased from 0.03 ppm at all depths in the fall/winter of 1971/1972 to 1.25 ppm at 60 cm, 1.00 ppm at 90 cm, and 0.85 ppm at 120 cm by fall 1974. During the same period, K increased from 0.05 ppm at all three depths to 14 ppm; however, NO3‐N was consistently below 1.0 ppm. The effluent contained an average of 2.2 ppm NO3‐N, 14 ppm Kjeldahl N, 2.8 ppm P, and 16 ppm K. Laboratory tests of the soil indicated satisfactory nitrification; however, adverse conditions in the field probably curtailed the nitrifying process.
Lead Effects on Several Enzymes and Nitrogenous Compounds in Soybean Leaf
Authors: Lee K. C. , Cunningham B. A. , Chung K. H. , Paulsen G. M. , Liang G. H.
Published: July 2010

To obtain further evidence on the nature of lead toxicity in plants, we investigated the Pb2+ effect of several enzyme activities and nitrogenous compounds in soybean (Glycine max L. cv. Columbus). Soybean seedlings were grown in culture solution treated with lead nitrate so that final concentrations of lead (Pb2+) were 0, 20, 60, and 100 mg/liter. Soybean leaves were analyzed 10 days after lead was added to the solution.

Results showed increased respiration rate, increased activities of acid phosphatase, peroxidase and alpha‐amylase, and increases in soluble protein and ammonia. There was no significant change in malic dehydrogenase, and total free amino acids. A decrease was observed for glutamine synthetase activity and nitrate. Leaf calcium and phosphorus decreased as the lead concentration was increased in the culture solution.

Increased activities of the hydrolytic enzymes and peroxidase indicates that the lead treatment enhances senescence.
Persistence of Aerially Applied Hexachlorobenzene on Grass and Soil
Authors: Beall M. L.
Published: July 2010

The persistence of aerially applied hexachlorobenzene (HCB, C6Cl6) (equivalent to 10 ppm in the top 5 cm of soil) in “simulated” pasture was followed for 19 months in the greenhouse. The hypothesis that burning off the grass canopy would decrease the persistence of HCB in soil was also tested. Gas‐liquid chromatographic analysis revealed no degradation products of HCB in plant or soil samples and that burning off the grass had no significant effect on subsequent persistence of HCB in soil. On day 1 (20 hours after application) the top 2 cm of soil contained 5.60 ppm HCB. Concentrations (air‐dry basis) found after 0.5, 1, 6.5, 12, and 19 months were 45.2%, 24.4%, 7.9%, 4.7%, and 3.4% of day 1, respectively. Concentration in the 2‐ to 4‐cm layer averaged 0.11 ppm with no significant change over the 19 months. Day 1 grass samples contained 1,060 ppm HCB, but after 2 weeks only 15.6 ppm (1.5% of day 1) were found. Concentrations after 1, 6.5, 12, and 19 months were 0.66%, 0.06%, 0.01%, and < 0.01% of day 1, respectively. HCB appears to volatilize rapidly from plant and soil surfaces but could be persistent within the soil.
Behavior of Chromium in Soils: I. Trivalent Forms
Authors: Bartlett R. J. , Kimble J. M.
Published: July 2010

Chemical behavior of Cr(III) was studied in solutions, soil suspensions, and in soils of contrasting characteristics incubated at field capacity moisture. Sodium pyrophosphate, pH 4.8 NH4OAc, and 0.1M NaF appeared to extract organically bound Cr(III), whereas 1M HCl removed inorganic Cr hydroxides and phosphates along with some organic Cr. Pyrophosphate and HCl extracts represented quantities of Cr(III) removed; NH4OAc and NaF extracts appeared to characterize small readily removed fractions, that is, intensity factors.

Soil organic complexes of Cr(III) formed at low pH and appeared to remain stable and soluble even when soil pH's were raised to levels where the Cr would be expected to precipitate. Adsorption and solubility behavior of Cr(III) as it varied with pH and treatments was similar to that of Al.

Oxidation of Cr(III) to Cr(VI) was not demonstrated at all, under conditions of maximum aeration and high pH.
Behavior of Chromium in Soils: II. Hexavalent Forms
Authors: Bartlett R. J. , Kimble J. M.
Published: July 2010

Adsorption and reduction of added Cr(VI) were characterized in soils with contrasting pH's, organic matter contents, and chemical and mineralogical properties.

Presence of soil organic matter brought about spontaneous reduction of Cr(VI) to Cr(III), even at pH's above neutrality. Reduction did not occur in soils very low in organic matter unless an energy source was added. Cow manure added to practically organic‐free Cecil B2 reduced Cr(IV) only after the pH had been lowered below 3 with HCl.

The solubility of Cr(VI) in the presence of excess Al changed in a pattern remindful of orthophosphate. All of the soils, except a pH 7.8 Cca horizon material, adsorbed Cr(VI). Presence of orthophosphate prevented the adsorption of Cr(VI), presumably by competition for the adsorption sites. Consistent with this finding, KH2PO4 was found to be the best extracting agent for Cr(VI).

It was concluded that behavior of Cr(VI), if it remains in soils, is similar to that of orthophosphate. However, unlike phosphate, Cr(VI) is quickly reduced by soil organic matter. Thus, Cr(VI) added to a soil will remain mobile only if its concentration exceeds both the adsorbing and the reducing capacities of the soil.
Redox Potentials and Denitrification in a Cropped Potato Processing Waste Water Disposal Field
Authors: Smith J. H. , Gilbert R. G. , Miller J. B.
Published: July 2010

Many potato processors apply processing waste water containing nitrogen and other plant nutrients to cropped land. More than 1 metric ton of N per hectare was applied each year when waste water application averaged 230 cm/year on one field for 2 years. Less than 300 kg N/ha was recovered in the harvested grass hay, and only about 15 kg N/ha leached each season. Redox measurements made at several depths from 5 to 150 cm showed poorly aerated zones in the soil profile because of a high water table during the summer. Under these conditions, nitrate leached into these poorly aerated zones would be denitrified. Sufficient decomposable organic matter was present to provide energy for denitrification.
Uptake of Plutonium and Americium by Barley from Two Contaminated Nevada Test Site Soils
Authors: Schulz R. K. , Tompkins G. A. , Leventhal L. , Babcock K. L.
Published: July 2010

Barley (Hordeum vulgare, Var. Atlas 68) plant uptake of 239,240Pu and 241Am was studied using two soil samples collected from widely separated areas of the Nevada Test Site. Each area had been previously contaminated with plutonium and americium as a result of a separate high explosive (nonnuclear) detonation of a device containing plutonium. The plants were grown on 3‐kg soil samples in a controlled environment chamber. The plutonium concentration ratio (plutonium concentration in dry plant tissue/plutonium concentration in dry soil) was in the order of 10−5 for plant vegetative material. The plutonium concentration ratio for the grain was 20–100 times lower than that in the vegetative material. Concentration ratios for americium were in the order of 10−4 for vegetative growth and 25–75 times lower for the grain. These results imply that americium is more available to plants than plutonium.

Plutonium‐bearing particles were identified in a soil sample using an autoradiographic technique and then separated from the soil samples. The 239Pu oxide equivalent diameters of plutonium‐bearing particles could be described by a log‐normal distribution function in the range of 0.2 to 0.7 µm. The actual diameters of the particles were 2 to 3 times the PuO2 equivalent diameter. Microprobe analyses of the surface region of particles >2 µm showed the following order of abundance: U, Pu > O > Al > Si > Fe > Mg. Photographs obtained with a scanning electron microscope revealed that some of the particles are quite irregular and have large specific surface areas which might enhance solubility and plant uptake.
Elimination of Fecal Coliform Bacteria from Reed Canarygrass Irrigated with Municipal Sewage Lagoon Effluent
Authors: Bell R. G. , Bole J. B.
Published: July 2010

The survival characteristics of fecal coliform bacteria on reed canarygrass (Phalaris arundinacea L.) irrigated with municipal sewage effluent were determined using the most probable number (MPN) technique to develop a recommendation for sunlight decontamination of Gramineae species. The grass was recontaminated during rainfall because contaminated soil was splashed onto the foliage, and the number of fecal coliforms was not reduced during cool, damp periods.

Exposure to 50 hours bright sunlight under semiarid prairie conditions was sufficient to destroy virtually all those fecal coliforms present on the grass after irrigation with sewage effluent containing about 3.2 × 104 fecal coliforms/100 ml. This was considerably longer than the 10 hours previously shown to be adequate to eliminate fecal coliforms from alfalfa (Medicago sativa L.). We believe that this difference between species is due to the presence of leaf sheaths on the grass in which effluent could collect and be protected from the bacteriocidal effects of bright sunlight.
Cadmium Distribution in Forest Ecosystems Irrigated with Treated Municipal Waste Water and Sludge
Authors: Sidle R. C. , Sopper W. E.
Published: July 2010

Treated municipal waste water was irrigated in an abandoned old field area from 1964–1974 and in a mixed hardwood area (old gamelands) from 1964–1974. Total applications of Cd in the old field and old gamelands areas were 0.47 and 0.61 kg/ha, respectively. White spruce (Picea glauca Moench Voss.) and wild strawberry (Fragaria virginiana Duchesne) foliage sampled from the old field showed no increase in Cd concentrations due to effluent irrigation, while goldenrod (Solidago sp. Ait.) had lower Cd levels in the treated area than in the unirrigated control area. Foliage sampled from red maple (Acer rubrum L.), white oak (Quercus alba L.), and wild sarsaparilla (Aralia nudicaulis L.), in the old gamelands, showed no increase in Cd as a result of waste water irrigation. Soil Cd levels were not significantly affected by waste water irrigation in either area, except for the increase in soil Cd in the 0–5 cm depth of the old gamelands. The Cd/Zn ratios of the vegetation foliage were not significantly different between the treated and control areas.
Selectivity and Soil Persistence of Certain Herbicides Used on Perennial Forage Grasses
Authors: Morrow L. A. , McCarty M. K.
Published: July 2010

Several herbicides were applied in the field to the cool‐season grass smooth brome (Bromus inermis Leyss.) and to three warm‐season grasses, sideoats grama [Bouteloua curtipendula (Michx.) Torr.], switchgrass (Panicum virgatum L.) and indiangrass [Sorghastrum nutans (L.) Nash] to evaluate herbicide persistence in soils supporting each of these perennial forage grasses. Herbicides were applied once and the soil was sampled to a depth of 91 cm, 4 and 16 months after application. Bioassays, with soybeans [Glycine max (L.) Merr.] as the test crop, were conducted in the greenhouse to determine the location of the herbicides in the soil profile.

Most herbicide residues 4 or 16 months after application were located in the 0‐ to 8‐cm soil depth. Only bromacil (5‐bromo‐3‐sec‐butyl‐6‐methyluracil), karbutilate [tert‐butylcarbamic acid ester with 3‐(m‐hydroxyphenyl)‐1,1‐dimethylurea] or terbacil (3‐tert‐butyl‐5‐chloro‐6‐methyluracil) at high rates depressed soybean growth in soil from the 8‐ to 15‐cm depth. Four months after herbicide application, a slight increase in soybean growth was evident in soil from the 15‐ to 30‐cm depth where bromacil, karbutilate, or terbacil had been applied to bromegrass.

Germination of seed harvested from each grass was not affected by herbicide treatments.
Nitrification‐Denitrification Reactions in Flooded Soils and Water Bottoms: Dependence on Oxygen Supply and Ammonium Diffusion
Authors: Patrick W. H. , Reddy K. R.
Published: July 2010

Ammonium nitrogen in a flooded soil or water bottom exposed to oxygen from the water column undergoes sequential nitrification and denitrification. Oxygen moving through the overlying water column causes the development of an aerobic surface layer of soil or sediment. Ammonium in this aerobic surface layer is nitrified and the resulting ammonium concentration gradient across the aerobic layer and the underlying anaerobic layer causes ammonium in the anaerobic layer to diffuse upward into the aerobic layer where it also undergoes nitrification. Nitrate produced in the aerobic layer then diffuses downward into the anaerobic layer where it is denitrified to N2 and N2O. Nitrate derived from ammonium nitrogen in the aerobic layer appears as an intermediate product in the nitrification‐denitrification reaction.

A laboratory experiment utilizing 15N as a tracer showed that approximately one‐half of the nitrogen involved in the nitrification‐denitrification process was ammonium originally present in the surface aerobic soil or water bottom layer with the remainder diffusing up from the underlying anaerobic layer. Where oxygen was absent or limiting, nitrification either did not occur or occurred at a lower rate, resulting in a reduced amount of nitrate available for the denitrification process.
Distribution of Soil Fluorides Near an Airborne Fluoride Source
Authors: McClenahen James R.
Published: July 2010

The purpose of the study was to determine the effect of a major source of airborne fluorides on the geographical distribution of total fluoride in soils. Total fluoride determinations were made on soil samples collected from the same pastures at different distances from the source in spring and fall of 1973 and 1974. Samples were collected at depths of 0–5, 5–15, and 15–30 cm. Forage fluoride levels were used to determine areas of relatively high and low airborne fluoride impact, and soil sampling locations within these respective areas were segregated accordingly. Total soil fluoride increased with depth at low fluoride impact sites, but decreased with depth at high impact sites. This was a result of significantly (p = 0.05) elevated fluoride levels at the 0–5 cm depth on high impact sites compared to low impact areas. Total soil fluoride for all depths decreased with distance from the fluoride source, and approximated background levels at about 10 km. It is concluded that the observed magnitude of atmospheric fluoride contribution to total soil fluoride will probably have no significant impact on agriculture.
The Environmental Fate of Three Dichlorophenyl Nitrophenyl Ether Herbicides in a Rice Paddy Model Ecosystem
Authors: Lee An‐Horng , Lu Po‐Yung , Metcalf Robert L. , Hsu Err‐Lieh
Published: July 2010

The distribution and fate of three 14C radiolabeled diphenyl ether herbicides, nitrofen (2,4‐dichlorophenyl 4′‐nitrophenyl ether), X‐52 or methoxy‐nitrofen (2,4‐dichlorophenyl 3′‐methoxy‐4′‐nitrophenyl ether), and bifenox (2,4‐dichlorophenyl 3′‐carbomethoxy‐4′‐nitrophenyl ether), were evaluated in a laboratory rice (Oryza sativa L., Taichung Native No. 1) paddy model ecosystem. Nitrofen was relatively stable under model ecosystem conditions and was bioconcentrated and stored over a 33‐day period in tissues of alga (Oedogonium cardiacum Wittrock), snail (Physa sp.), mosquito (Culex pipiens quinquefasciatus Say), and fish (Gambusia affinis Baird & Girard). The carbomethoxy group of bifenox served as an effective degradophore and tissue storage of the parent compound was minimal. The methoxy group of the methoxynitrofen was not an effective degradophore. The laboratory rice paddy model ecosystem is a useful tool for evaluating the environmental effects and fate of pesticides to be used in rice culture.
Effect of Cacodylic Acid and MSMA on Nitrogen Transformations in Forest Floor and Soil
Authors: Bollen W. B. , Norris Logan A. , Stowers Kathleen L.
Published: July 2010

Cacodylic acid (hydroxydimethylarsine oxide) had no statistically significant effect on ammonification in three forest floors or three forest soils treated with 500 mg/kg peptone‐nitrogen, and up to 1,000 mg/kg arsenic as cacodylic acid. MSMA (monosodium methanearsonate) caused an increase in ammonification which was linear with the logarithm of the arsenic concentration. Decreased nitrification appeared to be related to the logarithm of increased arsenic concentration. The nitrification potential was low in test substrates; however, and the magnitude of the chemically induced depression of nitrification was small. The concentrations of arsenic which occur in forest floor and soil after precommercial thinning with MSMA and cacodylic acid should not have a significant adverse effect on nitrogen metabolism of forest floor and soil microorganisms.
Predicting Effects of Sulfuric Acid on Qualities of Irrigation and Drainage Waters in Calcareous Soils
Authors: Miyamoto S.
Published: July 2010

Considerable quantities of sulfuric acid (H2SO4) are being utilized in the southwestern United States for soil and water treatment. Future acid production may exceed demand and thus require disposal in some manner. Acid application or disposal to soils and water raises a question concerning effects on water quality. A numerical method is thus presented for predicting the effects of H2SO4 on qualities of irrigation and drainage waters, excluding trace elements, in calcareous systems. The method is based on known relations between ion equilibria and the solubility of calcite, magnesite, and gypsum. Computed results are presented for acid applied to waters or to soils under several hypothesized conditions, and compared with some reported laboratory or lysimeter data. Results indicate: (i) the numerical method is a promising tool, but requires further experimental verification; (ii) acid effects on water quality depend strongly on CO2 partial pressure and properties of soils and water, besides application rates; and (iii) the assumption that acid application produces equivalent amounts of soluble salts is an oversimplification.