bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soda Ash Treatment of a Strontium‐90‐Contaminated Groundwater Seep
Authors: Spalding B. P. , Munro I. L. 
Published: July 2010

AbstractA 90Sr‐contaminated groundwater seep on the perimeter of a low‐level radioactive solid waste disposal area at the Oak Ridge National Laboratory (ORNL) was treated by burying 315 kg of soda ash in the groundwater flow path leading to the seep, and placing 45 kg of soda ash on the surface of the seep. The concentration of 90Sr in the seep water fell from an average of 7000 Bq L−1 to 900 Bq L−1 for the 90 d after burial, followed by a period of gradual rise back to pretreatment levels over the next 100 d. The electrical conductivity and pH of the seep water increased following soda ash burial, while water hardness fell. Hardness was highly correlated (r = 0.84) with 90Sr concentrations over the entire 2‐year observation period, indicating the similar behavior of 90Sr and soluble Ca and Mg. This in situ softening of, and 90Sr precipitation from, the seep water was achieved by coprecipitation of 90Sr with Ca(Mg)CO3 until the buried soda ash was depleted by dissolution in the groundwater. The soda ash treatment of groundwater seeps appears to be most practical as an interim technique for those situations requiring an immediate, but temporary, corrective action. During this limited but effective period, more permanent corrective actions could be planned at the source of contamination. The electrical conductivity, pH, and hardness of the larger surface stream, into which this seep discharges, were not affected by the soda ash burial, most likely due to the approximately 2000‐fold dilution effected by this stream.
Influence of Ozone, Sulfur Dioxide, and Salinity on Leaf Injury, Stomatal Resistance, Growth, and Chemical Composition of Bean Plants
Authors: Bytnerowicz A. , Taylor O. C. 
Published: July 2010

AbstractBean plants (Phaseolus vulgaris L. var. ‘Bush Blue Lake no. 274’), growing in half‐strength Hoagland solutions modified to provide three salinity levels of −40, −240, and −440 kPa, were exposed four times to 390 µg m−3 O3, 520 µg m−3 SO2, and 390 µg m−3 O3 + 520 µg m−3 SO2. Fumigations were performed between 0900 and 1600 hours. Environmental conditions during fumigation were: temperature 25–35° C, relative humidity 43–51%, and photon flux density 200–600 µmol m−2 sec−1. Plants fumigated with SO2 alone showed no injury. Primary leaves of O3‐treated plants were injured more than those of plants fumigated with the combination of O3 and SO2. Pollutant injury to leaves decreased as salinity increased. Stomatal resistance on the abaxial surface of primary leaves of SO2, and especially of (O3 + SO2)‐treated plants, increased sharply during fumigations, and returned to prefumigation levels the next day. Stomatal resistances of O3‐treated plants were similar to nonfumigated plants during the first phase of the experiment, but after the last fumigation, this resistance returned to essentially normal only in plants growing at the highest salinity level. Plant growth was suppressed by increased salinity. Root growth on O3‐ and (O3 + SO2)‐treated plants was reduced at all salinity levels. As salinity increased, plants accumulated Cl and Ca. Sodium increased in stems and roots, and decreased in leaves of plants grown in high Na‐nutrient solutions. Plants fumigated with SO2 and (O3 + SO2) had higher S content in roots than nonfumigated and O3‐treated plants. The highest S content in leaves was found in SO2‐treated plants at the −40 kPa salinity level. Accumulation of Ca in leaves and of Mg in roots was lowest in plants fumigated with O3 alone and (O3 + SO2). Plants fumigated with O3 alone and (O3 + SO2) accumulated more K in stems and leaves, and more Fe in roots and leaves, compared with nonfumigated and SO2‐treated plants. The O3 and (O3 + SO2) effects on mineral content of the plants was suppressed by salinity, and the pollutant treatments had no statistically significant effect on mineral content of plants growing at −440 kPa salinity.
Organochlorine Residues in Sediment Cores of a Midwestern Reservoir
Authors: Ricci Edward D. , Hubert Wayne A. , Richard John J. 
Published: July 2010

AbstractOrganochlorine residues detected in sediment core samples collected from Rock Reservoir, Iowa, in early 1981 were < 5 µg/kg dry weight for dieldrin (1,2,3,4,10,10‐hexachloro‐exo‐6,7‐epoxyl,4,4a,5,6,7,8,8a‐octahydro‐1,4‐endo, exo‐5,8‐dimethanophthalene), p,p′‐DDE (1,1‐dichloro‐2,2‐bis(p‐chlorophenyl) ethylene), p,p′‐DDD (1,1‐dichloro‐2,2‐bis(p‐chlorophenyl)ethane), and < 16 µg/kg for PCB's (polychlorinated biphenyls). The mean concentration of PCB residues (13 µg/kg) was higher than that of the three insecticides (dieldrin, 2.9 µg/kg; DDE and DDD, 2.4 µg/kg each). Concentrations of organochlorine contaminants in sediments were higher at the upper and lower ends of the reservoir than at midreservoir locations. Deposition of organochlorine residues did not correlate well with either clay or organic composition of the sediment. A mechanism not related to clay‐organic sediment appears to be influencing accumulation of organochlorines in the upper end of the reservoir. In the river channel, dieldrin levels were higher than at loations on either side of the channel, while no variation due to transect location was noted for DDE, DDD or PCB's. Dieldrin concentrations were highest in surficial sediments, whereas those of PCB's, DDE, and DDD were highest near the bottom of core samples. An estimated 53 kg of PCB's, 17 kg of dieldrin, 14 kg of DDD, and 9.3 kg of DDE were present in the top 7.5 cm of sediment over Red Rock Reservoir's 3600 ha.
Polycyclic Aromatic Hydrocarbons (PAH's) in the Terrestrial Environment—A Review
Authors: Edwards Nelson T. 
Published: July 2010

AbstractThis review, while touching on sources of polycyclic aromatic hydrocarbons (PAH's) and their degradation, emphasizes research that addresses their fate in the terrestrial environment. Typical endogenous concentrations of PAH's in soil and vegetation range from 1 to 10 µg/kg and from 10 to 20 µg/kg, respectively. Endogenous PAH's are due to plant synthesis, forest and prairie fires, volcanoes, etc. Anthropogenic sources are primarily from fossil fuel burning. Estimated annual release of benzo(a)pyrene (BaP) from fossil fuel combustion is 4.6 × 106 kg. Concentrations of PAH's in air, soil, and vegetation vary with distances from known sources. Reported BaP concentrations in air of nonurban areas of the United States ranged from 0.01 to 1.9 µg/m3; concentrations in urban areas ranged from 0.1 to 61.0 µg/m3. Concentrations of BaP in soil may typically reach 1000 µg/kg, and values exceeding 100 000 µg/kg have been reported near known sources. Typically, concentrations for total PAH's (usually the sum of 5 to 20 PAH's) exceed BaP concentrations by at least one order of magnitude. The maximum PAH concentration in vegetation growing near a known source was 25 000 µg/kg, but values more typically range from 20 to 1000 µg/kg. Reported BaP concentrations in vegetation ranged from 0.1 to 150 µg/kg. Concentrations in vegetation were generally less than those in soil where the plants were growing. Concentration ratios (concentration in vegetation/concentration in soil) ranged from 0.0001 to 0.33 for BaP and from 0.001 to 0.18 for the sum of 17 PAH's tested. However, laboratory experiments demonstrated that plants can concentrate PAH's above those found in their environment. Controlled experiments with a few PAH's demonstrated uptake by both leaves and roots and subsequent translocation to other plant parts. Washing leaves of vegetation contaminated with PAH's removes no more than 25% of the contamination. There is some evidence that plants can catabolize PAH's, but metabolic pathways have not been defined well.
Acidic Precipitation Effects on Crops: A Review and Analysis of Research
Authors: Irving Patricia M. 
Published: July 2010

AbstractFor more than a century it has been known that vegetative growth is affected by the products of fossil fuel combustion. Recently, the acidic deposition phenomenon has gained increasing attention, especially when implicated as a factor responsible for economic loss. Research has been directed toward quantification of effects; however, limitations in the design of many crop studies restricts the usefulness and applicability of the results. Acidic deposition varies in a number of ways that may affect crop yield (i.e., level of acidity, amount and intensity of rain, S and N doses). The responses to these variables may be nonlinear. To allow comparisons of published acid precipitation effects research, calculations for this review were made (based on information in the literature or from personal communication) to describe the experimental conditions, the various dose parameters, and the responses in comparable units for each investigation.The majority of crop species studied in field and controlled environment experiments exhibited no effect on growth nor yield as a result of simulated acidic rain. The growth and yield of some crops, however, was negatively affected by acidic rain; others exhibited a positive response. This analysis of the current literature concludes that the effects of acidic precipitation on crops appear to be minimal and that when responses are observed, they may be positive or negative. More complex experimental designs and analyses may be necessary in order to examine and describe the possible subtle responses of agricultural systems to acidic precipitation.
Effects of Acidity and Alkalinity on the Stability of Amidohydrolases in Freshwater
Authors: Frankenberger W. T. , Page A. L. 
Published: July 2010

AbstractThe influence of acidity and alkalinity on the enzymatic hydrolysis of amide‐N in the aquatic system was investigated by determining the stability of L‐asparaginase (EC [Enzyme Commission] 3.5.1.1). L‐glutaminase (EC 3.5.1.2), and amidase (EC 3.5.1.4), and urease (EC 3.5.1.5) with respect to pH in three freshwater lakes. The water samples were first incubated at the indicated buffer pH (1–13) for 24 h; then each enzyme was assayed at its optimal pH (pHopt) under standardized conditions. L‐Asparaginase retained essentially 100% of its activity within the pH range of 6–7 in Lake Evans and Lake Matthews, and 5–7 in Lake Perris. L‐Glutaminase was active between pH 6 and 7 in the water samples surveyed. Amidase remained completely active at pH ranges of 4–8 in Lake Evans, 4–7 in Lake Matthews, and 5–8 in Lake Perris. Urease remained active over a broad pH range of 5–9 in Lake Evans, 5–8 in Lake Matthews, and 4–8 in Lake Perris. There was a progressive loss in enzyme activity below and above these pH ranges. The results suggest that the decline in aquatic amidohydrolase activities in relation to the pH‐profile near their pHopt was caused by a reversible reaction involving the ionization or deionization of functional groups of the active center of the protein, but under highly acidic or alkaline conditions (pH < 4 to > 9) the reduced activity appears to be due to irreversible inactivation of the enzyme.
Trace Metal and Mineral Composition of Milk and Blood from Goats Fed Silage Produced on Sludge‐Amended Soil
Authors: Dowdy R. H. , Bray B. J. , Goodrich R. D. 
Published: July 2010

AbstractThe transfer of heavy metals from sewage sludge into the food and feed chain is a significant concern to the health of humans and animals. We measured the accumulation of trace metals in the milk and blood of dairy goats (Capra hircus) fed corn (Zea mays L.) silage grown on sludge‐amended vs. conventionally fertilized soil for 3 consecutive years. The silage contained levels of Cd up to 5.3 mg/kg. Zinc, the only other sludge‐borne metal that was accumulated by corn, was accumulated to a lesser extent than Cd, which resulted in low Zn/Cd ratios.The Cd concentrations of goat milk were not increased, even though the animals received as much as 5 mg Cd each day from corn silage containing high levels of bioaccumulated Cd.Zinc levels in milk decreased as the amount of silage‐borne Zn increased within the three treatments fertilized with sludge, but no differences were noted when the control treatment was contrasted with all sludge treatments. Goat's milk from animals on the control treatment contained higher levels of Cu than milk from animals of the various sludge‐fertilized treatments. The higher levels of Cd in silage from the sludge‐amended treatments may have limited Cu absorption by the animals.The elemental concentrations of 14 other metals and minerals in milk were not affected by treatment nor time within the lactation period. Although colostrum generally contained higher concentrations of most minerals, no treatment effect was observed. As was true with milk composition, Cu was the only element in blood that was consistently affected by treatment. Copper levels in blood were higher for animals of the control treatment, even though all animals received a Cu‐containing trace mineralized salt ad libitnm.
Heavy Metals in Northern Fur Seals (Callorhinus ursinus) from the Pribilof Islands, Alaska
Authors: Goldblatt Craig J. , Anthony Robert G. 
Published: July 2010

AbstractSamples of liver, kidney, muscle, and bone were collected from northern fur seals (Callorhinus ursinus) from St. Paul Island, Alaska during the summer of 1975 and analyzed for Cd, Zn, Pb, Ni, and Hg. Positive correlations existed between age of the seals and concentrations of Cd in liver, muscle, and bone, and Hg in liver. Concentrations of Zn, Pb, and Ni were not significantly correlated with age. Cd residues in kidney and liver samples were higher than those reported in 1970–1971 for the same species, suggesting increased contamination of this metal in the food chain of northern fur seals. Concentrations of Pb and Ni were low and those of Zn were similar to levels found in other mammals, including man. Levels of Hg were considerably lower than those reported for other pinnipeds. Among the four tissues sampled, Cd and Zn concentrations were significantly higher in kidneys, whereas concentrations of Pb and Ni were highest in bone.
Suspended Solids and Phosphorus Loads from a Clay Soil: I. Plot Studies
Authors: Culley J. L. B. , Bolton E. F. , Bernyk V. 
Published: July 2010

AbstractPhosphorus and suspended solids (SS) contents in tile discharge from two southwestern Ontario clay soil drainage experiments were measured over a 2‐y period. For continuous corn (Zea mays L.) plots, loads of SS and total P were 407 and 0.88 kg ha−1 y−1, respectively. Suspended solids and total P loads from drains beneath permanent sod were 97 and 1.85 kg ha−1 y−1, respectively. Comparison of these results with limited data on P and SS loads in surface runoff indicated that >50% of the total P load from these nearly level plots may be lost via subsurface tile flow. Overall, 34% of the total P load from subsurface drains was sediment‐associated. Furthermore, crop cover, P fertilization rate, and tile drain depth were found to significantly affect dissolved P export. Dissolved P concentrations in effluent from permanent bluegrass sod exceeded those from continuous corn and rotational plots. Subsurface sediment and sediment‐associated P loads were highest from continuous corn. Greater soil cover over the tile line decreased both sediment and P concentrations. Sediment‐associated P concentrations increased with P fertilization rate at one of the experimental locations.
Nitrogen Loss from Freshwater and Saline Estuarine Sediments
Authors: Smith C. J. , De Laune R. D. 
Published: July 2010

AbstractThe magnitude of ammonium‐N (NH4+‐N) loss from nitrification‐denitrification reactions in bottom sediments collected from saline and freshwater Louisiana Gulf Coast lakes was determined. Studies were conducted in the laboratory and field. Maximum gaseous N accumulation, from fresh‐water and saline sediment amended with 4.5 µg nitrate‐N (NO4−‐N) g−1 (on dry‐wt basis), was 1.6 and 1.4 µg N g−1, respectively. The addition of 50 µg NH4+‐N g−1 stimulated the evolution of N2O from both sediments, and represents 0.02 and 0.2% of the NH4+‐N applied to the saline and fresh sediment, respectively. Nitrous oxide (N2O) emissions measured in the field were low. The annual N2O emission was 10 and 34 mg N m−2 from the saline and freshwater lakes. These values agree closely with the N2O emission rates calculated from laboratory data.Denitrification was also estimated from NH4+‐N amended sediment using the acetylene (C2H2) inhibition technique and 15N balance. Recovery of 15N decreased rapidly during the 0‐ to 8‐week period when high denitrification rates were measured. The denitrification rate estimated from 15N recovery during the 0‐ to 8‐week period was 3.7 mg N m−2 d−2 for each sediment. Approximately 50% of the added 15N was lost, an amount equivalent to 1.4 g N m−2 y−1. As the added 15NH4+‐N was incorporated into the organic N pool, little or no further 15N was lost.
Soil Sorption and Alfalfa Uptake of Strychnine
Authors: Miller Glenn C. , Miller W. W. , Hanks Larry , Warren John 
Published: July 2010

AbstractStrychnine (C21H22N2O2) sorption on soils and uptake in alfalfa (Medicago sativa L.) were investigated. Using application rates of 52–1040 mg/L strychnine, sorption isotherms were developed on three Nevada soils. Strychnine was found to sorb strongly to the three soils studied; however, isotherms were all nonlinear and the extent of sorption varied with each soil. Desorption characteristics paralleled sorption isotherms, indicating reversibility. Strychnine extraction with ammonium chloride (NH4Cl) solutions was greater than that obtained with water extraction on all soils. An apparent relationship between specific surface area, cation exchange capacity (CEC), and total strychnine sorption was noted. Strychnine movement through soil columns under saturated flow was also investigated for the three soils. These results were similar to the sorption studies in that the soil with the lowest sorptive capacity also required the fewest pore volumes for the eluting strychnine concentration to equal that of the starting concentration. The binding mechanism of strychnine to soil is suggested to be a combination of cation exchange and surface absorption to the organic and inorganic fractions of soil. Potential uptake of strychnine in alfalfa was investigated by applying treated milo (Sorghum vulgare var. subglabrescens) bait to the base of alfalfa plants at rates that exceeded normal rodent treatments. Strychnine was not detected (detection limit 0.03 mg/kg) in whole alfalfa samples taken 4 and 11 d following treatment. The data indicate that strychnine is relatively immobile in soil systems, particularly those of moderate‐to‐high CEC, and is not expected to leach rapidly nor be significantly taken up by plants.
Azinphosmethyl and Fenvalerate Runoff Loss from a Sugarcane‐Insect IPM System
Authors: Smith S. , Reagan T. E. , Flynn J. L. , Willis G. H. 
Published: July 2010

AbstractAzinphosmethyl {0,0‐dimethyl S‐[(4‐oxo‐1,2,3‐benzotriazin‐3(4H)‐yl)methyl] phosphorodithioate} and fenvalerate [(RS)‐α‐cyano‐3‐phenoxybenzyl (RS)‐2‐(4‐chlorophenyl)‐3‐methylbutyrate] were applied to sugarcane (Saccharum officinarum L.) runoff plots at rates of 0.84 and 0.22 kg/ha, respectively, 4 times each year in 1980 and 1981 as part of an insect integrated pest management (IPM) system research evaluation for season‐long control of the primary sugarcane insect pest, the sugarcane borer [Diatraea saccharalis (F.)]. Runoff samples (water + sediment) were collected within 8 h after each storm and analyzed by gas chromatography. In 1980, runoff losses of azinphosmethyl and fenvalerate were 0.08 and 0.02%, respectively, of the amount applied. Runoff in 1981 was about twice that in 1980, partially accounting for larger insecticide runoff losses measured, 0.55 and 0.56% of that applied for azinphosmethyl and fenvalerate, respectively. The larger 1981 losses also were attributed to shorter time intervals between insecticide applications and runoff events. Azinphosmethyl concentrations in runoff do not appear to be harmful to surrounding aquatic habitats, whereas fenvalerate concentrations might present problems, particularly if applied at 0.22 kg/ha rates.
Response of Soybeans to Simulated Acid Rain in the Field
Authors: Heagle Allen S. , Philbeck Robert B. , Brewer Patricia F. , Ferrell Ronald E. 
Published: July 2010

AbstractSoybeans [Glycine max (L.) Merr, ‘Davis’] were grown in the field during 1979 and 1980 to determine whether the acidity of simulated rainfall would affect plant injury, growth, or yield, soil chemistry, soil nematode populations, and Rhizobium nodulation of roots. Plants were exposed twice weekly to 0.74 cm (1979) or 0.85 cm (1980) of simulated rain at pH levels of 5.5, 4.0, 3.2, or 2.8 in 1979 and 5.4, 4.1, 3.2, or 2.4 in 1980. There were six 3‐m2 plots (replicates) for each pH level. Simulated rain at pH 2.8 or 2.4 caused small amounts of foliar injury evident as biracial white or tan lesions primarily on young leaves. However, plant growth, pod yield, foliar elemental content, seed protein content, seed oil content, Rhizobium nodulation of roots, and populations of parasitic nematodes were not affected. Soil analyses were performed before, midway through, and after each season. Trends toward lower soil pH, and less Ca, Mg, and K occurred with increased acidity of simulated rain. These effects were statistically significant only for soil pH, Mg, and K at treatment pH 2.4. Possible effects of ambient rain at current pH levels on agricultural soils are likely to require long‐term deposition.
Kinetics of the Microbial Degradation of 2,4‐D in Soil: Effects of Temperature and Moisture
Authors: Parker L. W. , Doxtader K. G. 
Published: July 2010

AbstractThe effects of soil moisture tension and temperature on the kinetics of the degradation of (2,4‐dichlorophenoxy)acetic acid (2,4‐D) in an Ascalon sandy loam were studied under laboratory conditions to develop a simulation model. Degradation occurred by a slow, first‐order reaction (slow phase) which, under some conditions, was followed by a rapid, first‐order reaction (fast phase). The optimum temperature and moisture tension were 27°C and 0.1 bar, respectively. Degradation rates under optimum conditions were 0.230 and 2.234 µg g−1 soil for the slow and fast phases, respectively. At temperatures above the optimum, no fast phase was observed. The activation energy (EA) values increased from 22.96 to 45.46 kcal mole−1, with increasing soil moisture tension in the range from 0.1 to 1.0 bar. The rate of decomposition of 2,4‐D decreased with increasing soil moisture tension for temperatures between 20 and 35°C. This decrease was a result of the reduced activity of the 2,4‐D‐degrading microorganisms arising from decreased water availability and increased 2,4‐D solution concentration.