bluuebunny/crossref_metadata_2025 huggingface dataset:
Use of Biological Filters for Treating Agricultural Drainage Effluents
Authors: Reddy K. R. , Campbell K. L. , Graetz D. A. , Portier K. M.
Published: July 2010

A field study was conducted for 1 year (1979–1980) to evaluate the efficiency of reservoir systems stocked with aquatic macrophytes for reducing nutrient levels of agricultural drainage water. Reservoir R2 containing water hyacinths (Eichhornia crassipes (Mart) Solms), R3 with elodea (Egeria densa Planch), and R4 with cattails (Typha latifolia L.) were connected in series by riser panels. Drainage water was pumped through the plant stands in the order of water hyacinths, elodea, and cattails. Drainage water was also pumped into a reservoir (R5) containing submerged Chara spp. Nutrient removal rates by each treatment system were calculated using water flow data.

Nitrate and ammonium removal rates by the treatment systems were in the range of 1–14 kg N/ha per day and 0.1–2 kg P/ha per day, respectively, while soluble P removal were in the range of 0.05–1.3 kg/ha per day. Reservoirs with aquatic macrophytes were found to be more effective than the reservoir containing Chara spp. About 78–81% of the input NO3− and NH4+, and 54% of the input soluble P were removed in 3.6 d by the R2 reservoir containing water hyacinths. Allowing the water to flow through an additional reservoir, R3, and increasing the residence time by an additional 3.6 d increased NO3− removal efficiency to 91% and soluble P removal efficiency to 71%, but NH4+ removal efficiency was not affected. Allowing the water to flow through the third reservoir (R4) and increasing the residence time by an additional 2.2 d, improved soluble P removal efficiency by an additional 14%.
Influence of Crude Oil and Refined Petroleum Products on Soil Dehydrogenase Activity
Authors: Frankenberger W. T. , Johanson J. B.
Published: July 2010

The effects of crude oil, leaded gasoline, kerosene, diesel fuel, and motor oil on soil dehydrogenase activity were investigated by contaminating three soils at three loading rates (20, 40, and 60% w/w oil/dry soil) and monitoring the activity up to 30 d of incubation. The levels of dehydrogenase activity in the contaminated soils were dependent on the amount and type of oil added. The highest level of dehydrogenase activity in all soils was observed with a 60% loading rate of crude oil 30 d after incubation. Dehydrogenase activity in soils contaminated with the refined oils (leaded gasoline, kerosene, diesel fuel, and motor oil) was extremely low when compared with the crude oil‐treated soils. When all soils were considered, the maximum activity of the dehydrogenase reaction (expressed in µg formazan/g soil per 24 h) was as follows: crude oil, 1,180; leaded gasoline, 56; kerosene, 32; diesel fuel, 56; and motor oil, 37. Generally, the maximum level of activity was observed at 30 d of incubation in the presence of crude oil, and at 7 d in the presence of refined oils. The increase in dehydrogenase activity was in proportion to the rates of oil application, in that activity increased with increasing loading rates. The lowest level of dehydrogenase activity (0.5 µg formazan/g soil per 24 h) was observed in the kerosene‐treated soils. These results suggest that any influence the oils may have on soil dehydrogenase activity is dependent on the chemical composition of the oil itself. The additives present in refined oils may have a major influence on the dehydrogenase reaction in soils.
The Effect of Cattle Grazing on Indicator Bacteria in Runoff From a Pacific Northwest Watershed
Authors: Jawson M. D. , Elliott L. F. , Saxton K. E. , Fortier D. H.
Published: July 2010

Total coliform (TC), fecal coliform (FC), and fecal streptococcal (FS) numbers were monitored for 3 years to determine the effect of grazing on the presence of these organisms in runoff from a cattle‐grazed and a nongrazed watershed in the Pacific Northwest. The watersheds were characterized by winter precipitation and summer grazing. Weighted‐average numbers of TC and FS in runoff did not appear to be appreciably different between the two watersheds during the study.

Numbers of TC in runoff from both watersheds routinely exceeded 10,000/100 mL. Prolonged absence of grazing animals did not seem to affect number of TC and FS in runoff from the check watershed. Each spring after a period of warm weather and prolonged absence of animals, there were increases in numbers of TC, FC, and FS in the runoff. There was some correlation between recentness of grazing and numbers of indicator bacteria in runoff. However, more than a year after animals were removed from the nongrazed check watershed FC numbers in runoff still exceeded 200/100 mL in many samples, and not until the following year did they drop to < 10/100 mL.

Sampling at several locations within the grazed watershed showed that sources of indicator bacteria were well distributed, and as a result were nonpoint after the initial runoff events. Thus, present FC recommendations developed for point‐sources would not apply adequately to grazed land in the Pacific Northwest. Indicator bacteria as presently analyzed would not provide a basis for developing best management practices.
Degradation of Atrazine in Estuarine Water/Sediment Systems and Soils
Authors: Jones T. W. , Kemp W. M. , Stevenson J. C. , Means J. C.
Published: July 2010

Herbicides have been postulated as a cause of the disappearance of submerged aquatic vegetation in the Chesapeake Bay. This research was undertaken to determine the longevity of 2‐chloro‐4‐ethylamino‐6‐isopropylamino‐s‐triazine (atrazine) in two estuarine water/sediment microcosm systems and two agricultural soil systems over an 80‐d period under aerobic and low‐O2 conditions. Atrazine degradation proceeded more rapidly in the estuarine systems than in the soil systems. The disappearance of atrazine from the estuarine water was relatively rapid, with the half‐life (50% remaining in the water column) of the parent compound ranging from 3 to 12 d. Atrazine half‐life was determined to be 15 and 20 d for the two estuarine sediments and 330 and 385 d for the two agricultural soils. Hydroxyatrazine (2‐hydroxy‐4‐ethylamino‐6‐isopropylamino‐s‐triazine) was the major short‐term metabolite in both the estuarine and terrestrial systems. By the 21st day of the experiment, the percent of total extracted residues corresponding to atrazine and hydroxyatrazine were: 65, 20 and 10, 85 for the two estuarine systems; and 66, 29 and 93, 5 for the two soil systems. Decreased O2 levels had little effect on atrazine degradation in the experimental systems. The rapid degradation of atrazine to hydroxyatrazine in estuarine water and sediment indicates a low probability for the accumulation of atrazine in the estuary.
Land Application of Untreated Industrial Waste Water
Authors: King Larry D.
Published: July 2010

Excessive pretreatment of waste water prior to land application unduly increases the cost and energy requirement of land treatment systems. This study was conducted to determine if untreated industrial waste water can be applied to soil without adversely affecting crop growth and soil properties or posing a ground‐water pollution hazard.

Untreated (UW) and treated (TW) waste water were diverted from the treatment plant at a fiberboard mill and spray‐irrigated on fescue‐grass (Festuca arundinacea Schreb) on Cecil soil (clayey kaolinitic, thermic Typic Hapludult) at 1.4 cm/week. After 2 years the treatments were changed to 1.5, 2.0, and 3.0 cm UW/week and continued for 2 more years.

Grass yields with UW and TW were equal to or greater than yields with inorganic fertilizer and no irrigation (control treatment). Recovery of waste‐water‐applied N via crop harvest ranged from 20 to 30%. Analysis of washed and unwashed grass samples showed that increased Mn concentrations were due to waste‐water solids adhering to the sample, rather than to increased Mn uptake. Concentrations of Ni, Pb, and Cr of unwashed samples were increased slightly but were far below concentrations toxic to livestock.

Soil nitrate concentrations resulting from UW applications were generally not significantly different from concentration in the control treatment except when UW contained appreciable quantities of inorganic N. There was evidence that denitrification was a significant N sink.

Waste‐water irrigation increased concentrations of soil P, K, and Ca and increased soil pH to 7.4–7.8. Sodium accumulated in the subsoil to an exchangeable‐Na percentage of 10.

Results of the study showed that extensive pretreatment was not necessary prior to irrigation with the waste water.
Mobility of 2,4‐D and 2,4,5‐T n‐Butyl Esters in Soils Following Massive Application to Field Mini‐Lysimeters
Authors: Majka Joseph T. , Cheng H. H. , Mc Neal B. L.
Published: July 2010

Concentrations of 2,4‐dichlorophenoxyacetic acid (2,4‐D) and 2,4,5‐trichlorophenoxyacetic acid (2,4,5‐T) in soils and leachates from field mini‐lysimeters were monitored for up to 28 months to characterize the patterns of herbicide mobility in soils under climatic conditions of the Palouse region of the Pacific Northwest. The lysimeters contained soils from Washington, Wyoming, or Mississippi, and were treated with 1,120 or 5,600 kg/ha of a 1:1 mixture of 2,4‐D and 2,4,5‐T n‐butyl esters in 1976, 1977, or 1978. The winter of 1976–1977 was mild and relatively dry, and little leachate could be collected. However, subsequent winters were wet and the soil columns were saturated by the following springs. Less than 1 ppm of 2,4‐D was found in leachates from Washington and Wyoming soils receiving the herbicide application in 1976 or 1977, though over 30 ppm was found in leachates from Washington soil treated in 1978. Over 10 ppm of 2,4‐D could be found in leachates from the acidic Mississippi soil receiving the high rate of herbicide application in 1977 or 1978. Concentrations of 2,4,5‐T in the same leachates were higher for the Washington and Wyoming soils, but lower (than corresponding concentrations of 2,4‐D) for the Mississippi soil. In all cases, 96–99% of the undegraded herbicides in the lysimeters remained in the 0‐ to 10‐cm soil layer after two to three winters, and only 0.14–1.65% of the 2,4‐D and 0.33–3.7% of the 2,4,5‐T remaining in the lysimeters were present in the 10‐ to 30‐cm depths. Mobility characterization by soil thin‐layer chromatography showed that the ester form of both herbicides was relatively immobile, the acid form was less mobile in the Mississippi soil than in the Washington and Wyoming soils, and 2,4‐D was slightly more mobile than 2,4,5‐T under corresponding conditions.
Chlortetracycline and Oxytetracycline Effects on Plant Growth and Development in Soil Systems
Authors: Batchelder A. R.
Published: July 2010

Antibiotics that are added to cattle feed have produced numerous benefits. However, when those antibiotics are excreted in manure and the manure is spread over cropland, plant growth and development might be affected. A series of greenhouse experiments was conducted to determine the effects of two antibiotics, chlortetracycline (7‐chloro‐4‐dimethylamino‐1,4,4a,5,5a,6,11,12a‐octahydro‐3,6,10,12,12a‐pentahydroxy‐6‐methyl‐1,11‐dioxo‐2‐naphthacenecarboxamide) and oxytetracycline (4‐[dimethylamino]‐1,4,4α,5,5α,6,11,12a‐octahydro‐3,5,6,10,12,12a‐hexahydroxy‐6‐methyl‐1,11‐dioxo‐2‐naphthacenecarboxamide) on plant growth and development in Ascalon sandy loam, an Aridic Argiustoll of the fine‐loamy, mixed, mesic family, and Nunn clay loam, an Aridic Argiustoll of the fine, montmorillonitic, mesic family. In sandy loam, the antibiotic concentrations were either 0 or 160 ppm. Edible radish (Raphanus sativus L.) yields, and the nutrient uptake of wheat (Triticum aestivum L.) and corn (Zea mays L.) were greater with either antibiotic than they were with the control treatment. Pinto beans (Phaseolus vulgaris L.) were affected by both antibiotics. Bean yields, plant heights, top and root dry‐weights, and the Ca, Mg, K, and N contents were all decreased by the antibiotics. Because only beans showed an adverse response in the sandy loam, they were the only plants grown in the clay loam. There were no antibiotic effects on the bean plants with either antibiotic in a concentration series of 0–160 ppm. The growth and development effects were related to soil characteristics and plant sensitivities.
Kinetics of Microbial Decomposition of 2,4‐D in Soil: Effects of Herbicide Concentration
Authors: Parker L. W. , Doxtader K. G.
Published: July 2010

The kinetics of the degradation of (2,4‐dichlorophenoxy) acetic acid (2,4‐D) in Ascalon fine sandy loam (Typic Ustoll) under laboratory conditions was studied in relation to herbicide concentration to test the feasibility of employing either the first‐order or Michaelis‐Menten equation to model the degradation of 2,4‐D. At 27°C, the herbicide degraded through two first‐order reactions: an initial slow rate (slow phase) followed by a fast rate (fast phase). The first‐order rate constants (k values) for the slow phase decreased as 2,4‐D concentrations were increased from 1.3 to 10.2 µg g−1 soil, and remained constant above the latter concentration. The k values for the fast phases of decomposition were independent of herbicide concentration. The duration of the slow phase increased linearly from 11 to 28 d as the herbicide concentration was increased from 1.3 to 25 µg g−1 soil.

When 2,4‐D degradation was measured during short incubation periods (instantaneous rates) to preclude growth of 2,4‐D‐decomposing organisms, the rates conformed to the Hane's linearization of the Michaelis‐Menten equation (r2 = 0.93). Apparent substrate inhibition occurred above herbicide concentrations of 40 µg g−1 soil. Instantaneous rates were measured for soil samples previously incubated for various times with 2,4‐D. Two significant peaks in activity (rate) were observed, one between concentrations of 4 and 9 µg g−1 soil, and the other between 20 and 40 µg g−1 soil. These data suggest the presence of two enzyme systems, differing with respect to the concentration at which substrate inhibition occurred.
Sewage Sludge Application to Calcareous Strip‐Mine Soil: I. Effect on Corn Yields and N, P, K, Ca, and Mg Compositions
Authors: Pietz R. I. , Peterson J. R. , Hinesly T. D. , Ziegler E. L. , Redborg K. E. , Lue‐Hing C.
Published: July 2010

A long‐term experiment using corn (Zea mays L.) was initiated in 1973 on calcareous strip‐mine spoil to evaluate the effects of anaerobically digested sewage sludge on the spoil‐crop system. Treatments consisted of a check (336‐224‐112 kg ha−1 year−1 N‐P‐K) and sewage sludge applications, weather permitting, at weekly rates of 0.64, 1.27, and 2.54 cm. In 5 years, 1973–1977, a total of 258 dry t ha−1 sludge was applied to maximum treatments.

Grain yields were significantly affected by sludge application in some years, but stover yields were not affected. Concentrations of N, P, K, Ca, and Mg in corn tissue varied in response to sludge applications. Leaf and grain P and grain K declined with higher rates of sludge application. The total uptake of the five elements by corn did not generally vary with the treatments, although there were yearly differences in uptake.

Factors affecting plant nutrition were investigated. Negative interactions were observed between leaf N and Mg and stover P and Zn. An evaluation of plant nutrient balance by the Diagnosis Recommendation Integrated System (DRIS) suggested that the order of required elements in corn from sludge treatments was most often P > K > N > Ca > Mg. For check treatments receiving only commercial fertilizer, the order of required nutrients was usually K > N > Ca > P > Mg. Considerable amounts of P were applied annually (365–2,690 kg ha−1) to maximum‐amended plots, and excessive P accumulation by corn may have been reduced by reactions with metals in the applied sludge, spoil, and plant tissue, and by a dilution effect from increased plant matter production.

Spoil factors (e.g., shallow rooting, soluble salts, and moisture stress) and plant element and/or spoil element interactions were important variables reacting with existing climatic conditions to influence corn yields and nutrient compositions.
Reevaluation of Partitioning as a Mechanism of Nonionic Chemicals Adsorption in Soils
Authors: Mingelgrin U. , Gerstl Z.
Published: July 2010

A critical evaluation of recent suggestions that the adsorption of nonionic organic compounds by soils can be well‐correlated with the partition of the compounds between an aqueous and a nonpolar phase (usually 1‐octanol), or with water solubility is presented. The physical basis proposed for these assumptions is that adsorption of nonionic organic compounds on soil organic matter is a “partition” process between the aqueous phase and a hydrophobic surface phase. The evidence presented in the literature for the dominance of a partition mechanism is insufficient to prove its general applicability. For example, systems in which a distinct hydrophobic phase at the solid surface does not exist are shown to exhibit the uptake behavior presumed to characterize partition. Theoretically, as well as practically, surface uptake cannot be simply defined as “adsorption” or “partition”, but rather there is a continuum of possible interactions starting with fixed site adsorption and ending with true partition between three‐dimensional phases.
Seasonal Disappearance and Volatilization of Toxaphene and DDT from a Cotton Field
Authors: Willis G. H. , Mc Dowell L. L. , Harper L. A. , Southwick L. M. , Smith S.
Published: July 2010

Volatilization and subsequent aerial transport is thought to be a major pathway of pesticide disappearance from application sites. Corroborative evidence obtained for agricultural pesticides under field conditions is scarce. The contribution of volatilization to the overall disappearance of toxaphene (chlorinated camphene) and DDT [1,1,1‐trichloro‐2,2‐bis(p‐chlorophenyl)ethane] from cotton (Gossypium hirsutum L.) was studied under field conditions in the “Delta” section of Mississippi. Drought conditions prevailed throughout most of the study. Measurements were made during two periods: (i) a 10.7‐d period after toxaphene was applied by ground equipment to 50‐cm‐tall cotton plants, and (ii) a 32.7‐d period after a similar application of a mixture of toxaphene and DDT to the same plants. Variable amounts of pesticide were unaccounted for (toxaphene, 17% first application, 54% second application; DDT, 72%) and were apparently lost during application and the following 3‐h period before sampling of air, soil, and plants was begun. The calculated 50% disappearance times of toxaphene (4.7 d, first application; and 10.8 d second application) and DDT (10.3 d) on plants agreed reasonably well with previously reported values. Pesticide disappearance rates were linear functions of the pesticide loads on the plants. The volatile loss of toxaphene (as quantified by the last four chromatographic peaks) during the 10.7‐d test period after the first application was 17% of the amount intercepted by the plants. The comparable volatile loss during the first 10.7 d after the second application (32.7‐d test period) was 33% of the amount on the plants. Total toxaphene and DDT volatile losses during the complete 32.7‐d test period were 53 and 58% of the amounts on the plants, respectively. Because of dry weather, no measurable pesticide volatilization occurred from soil. Disappearance rate changes, as well as volatilization rate changes, for toxaphene and DDT applied at the same time were approximately equal. The study provides additional evidence that post‐application volatilization from plants is a major pathway of pesticide transport.
Chemistry of Water‐Soluble, Metal‐Complexing Ligands Extracted from an Anaerobically‐Digested Sewage Sludge
Authors: Baham John , Sposito Garrison
Published: July 2010

Organic ligands extracted with deionized water from a representative municipal sewage sludge were studied by a variety of chemical techniques. The use of deionized water as an extractant of soluble organic matter from sewage sludge offered two advantages over NaOH: (i) the water soluble extract (WSE) represents an environmentally significant fraction, and (ii) counterion and inorganic ligand levels are comparable to those in FA extracts that have undergone tedious, extensive purification steps. Approximately 8% of the total sludge C was extracted with H2O. A charge balance calculation, including the major inorganic components of the WSE, yielded a value of 5 molc kg−1, for the cation exchange capacity (CEC) of the extracted organic matter. The molar organic C/N ratio for the WSE was found to be 6, indicating that the mixture is rich in polypeptide, amino sugar, and/or nitrogeneous base‐containing compounds. The presence of amino groups and carbohydrates was confirmed both by infrared (IR) identification and by direct chemical analysis. Amino acids accounted for 25% of the WSE organic carbon (CTS), with polysaccharides, hexosamines, and a steam‐volatile component accounting for 12, 9, 8.5% of the CTS, respectively. In total, 55% of the CTS in the WSE was identified as organic compounds that can form soluble complexes with transition metals. Gel filtration experiments suggested that approximately one‐half of the organic compounds in the WSE have relative molecular masses of < 1,500 daltons. The low molecular mass fraction of the WSE is composed primarily of aliphatic organic acids.
Effects of Surface Treatment and Interplanting of Shrub Alder on Growth of Douglas‐fir on Coal Spoils
Authors: Heilman Paul
Published: July 2010

Annual growth of Douglas‐fir (Pseudotsuga menziesii (Mirb.) Franco) planted on topsoiled spoils at a coal mine near Centralia, Wash., was monitored for the first 5 y after planting. Treatments were contour bedding, contour bedding plus interplanted Sitka alder (Alnus sinuata (Reg.) Rydb.), and unbedded control. The bedding significantly increased growth of Douglas‐fir in all 5 y of the study. Total height growth after 5 y was 35% greater than control on the bedding only plots, and 43% greater on the bedding plus Sitka alder plots. Height growth of Douglas‐fir in the mixed stand was significantly greater during the 2nd and 3rd y of the study, but after 5 y, no significant difference was evident in total height between the mixed and pure Douglas‐fir plots. Concentration of N in Douglas‐fir foliage was significantly increased by bedding in the fifth but not in the fourth year. Interplanting with Sitka alder had no significant effect on N in Douglas‐fir foliage.

The top 0.3 m of soil in the ridged portion of the bedded area contained significantly less moisture over a summer than did the top 0.3 m of the unbedded soil. At deeper depths, however, soil moisture was not significantly affected by bedding.

Wind damage caused by a severe storm that occurred after 5 y was very much greater on the unbedded plots (49% wind‐thrown vs. 9 to 15% wind‐thrown on the bedded plots) despite the smaller size of the trees on unbedded plots.
Response of Maryland Tobacco to Saline Aerosol Emissions From Brackish Water Cooling Towers
Authors: Mulchi Charles L. , Armbruster J. A.
Published: July 2010

Field studies were conducted on Maryland tobacco (Nicotiana tabacum L.) for 8 weeks during each summer from 1973 to 1977, to acquire information on the response of tobacco to simulated saline aerosol deposition from brackish water cooling towers. The studies involved two sources of salts (NaCl and brackish water from the Unit 3 cooling tower at Chalk Point, Md.), and various salt deposition rates (0.97 to 22.24 kg ha−1 week−1). Results obtained from these simulated drift studies were compared with results obtained from 12 monitoring sites located at 1.6‐, 4.8‐, and 9.6‐km distances from an operating natural‐draft cooling tower at Chalk Point, Md. over the period 1975 to 1978.

No foliar injury symptoms associated with salt deposition were observed in either the simulation drift studies or cooling tower monitoring program during the investigation.

In the simulated drift studies, regardless of salt sources or deposition rates, yield, average price, value, quality index, total alkaloid, and total N contents were found to be highly variable and generally non‐significant (p ≤0.05). However, trends for positive increases in yields were observed in four of the five studies at salt deposition rates ≤4.0 kg ha−1 week−1. No yield reductions were observed, even at salt deposition rates equal to 22.24 kg ha−1 week−1.

Statistically significant (p ≤0.05) increases in leaf Na and Cl contents, and decreases in metabolic index [MI = (% P + % K + % Ca + % Mg)/(% Na + % Cl)] values and leaf burn duration were observed with increased salt deposition rates in all five studies.

In the cooling tower monitoring program, no significant (p ≤0.05) differences were observed for yield, quality, burn, Cl contents or metabollic index value with respect to distances or years × distance interaction; however, year‐to‐year variation was significant. These resuits suggest that the operation of the Unit 3 cooling tower using brackish water was not having a significant impact on tobacco grown in the region.
Boron in Mine Soils and Rehabilitation Plant Species at Selected Surface Coal Mines in Western United States
Authors: Severson R. C. , Gough L. P.
Published: July 2010

Boron (B) content in mine soils and plants was assessed at 11 strip mines in the northern Great Plains, Powder River basin, and Green River coal regions. Except for unusually high B levels at one Wyoming mine, B levels in both mine soils and plants indicate that deficiency or toxicity conditions are minimal over this large geographic area. Relationships among mine‐soil pH, organic‐matter content, and hotwater soluble B, and B in plants are typical of those commonly reported in the literature. In addition, electrical conductivity (EC) of a water saturation extract of mine soil was positively correlated with B in mine soils. Regulations that suggest routine analysis for B to determine allowable levels in mine soils and rehabilitation plant species may be simplified. The more common measurements of pH and EC of mine soils should provide sufficient information to indicate potential B problem areas, where plant and mine soil analyses for B could then be performed.
Chemical Elements in Soils Under Cattle Pens
Authors: Dantzman C. L. , Richter M. F. , Martin F. G.
Published: July 2010

In cattle feedlots, the manure builds up and to some extent becomes incorporated into the soil profile through downward leaching and the stirring action created by the cattle. The object of this study was to measure the extent of build‐up of certain chemical elements resulting from the cattle wastes within the soil profile (Felda fine sand) in a cattle feedlot after 10 and 15 y. Soil samples were taken at 15‐cm increments from the soil surface to a depth of 137‐cm. Results indicated most of the increase of elements occurred near the soil surface. Within the soil profiles, the magnitude of increase of the chemical measurements compared with the control profile after 10 and 15 y were as follows, respectively: Mg, 23 and 39 times the amount in the control profile; P, 50 and 95; Ca, 11 and 29; K, 133 and 85; Mn, 4.4 and 9.5; Fe, 1.4 and 1.3; Cu, 2.5 and 4.2; soluble salts, 5.9 and 8.6; and percent organic matter, 1.6 and 5.1 times the amount in the control profile. The range of soil pH values increased from 3.6 to 4.7 for the control; from 7.8 to 9.1 after 10 y, and from 8.3 to 8.7 after 15 y.
Adsorption of Diuron and 2,4,5‐T on Soil Particle‐Size Separates
Authors: Nkedi‐Kizza P. , Rao P. S. C. , Johnson Jennifer W.
Published: July 2010

Equilibrium isotherms for the adsorption of herbicides, diuron, and 2,4,5‐T on whole soil and various‐size separates of Webster soil (Typic Haplaquolls) were measured. The Freundlich adsorption coefficient, K, for diuron varied by a factor of about 7 among the different particle‐size fractions. However, the sorption coefficient, K, normalized with respect to soil organic carbon (OC) content, denoted as Koc = (K/OC), varied only within a factor of 1.5. For 2,4,5‐T herbicide, the Koc values for the silt and clay‐size fractions, as well as the whole soil, were essentially identical and about 3 times larger than that for the sand‐size fraction. The results suggested that the soil particle‐size separates may be grouped into two size classes: “fine” (≤ 50 µm) and “coarse” (2,000‐50 µm). For a given pesticide, a specific Koc value may be assigned to each class.
Effects of Dried Sewage Sludge on Barley Genotypes
Authors: Day A. D. , Thompson R. K. , Tucker T. C.
Published: July 2010

An experiment was conducted at Mesa, Ariz. in 1976 and 1977 to compare the growth and grain yield of 16 barley (Hordeum vulgare L.) genotypes when grown with dried sewage sludge and inorganic fertilizers from commercial sources.

The genotypes were grown on a Laveen loam soil, which is a member of the coarse‐loamy, mixed, hyperthermic Typic Calciorthids. At planting in December of each year, three fertilizer treatments were applied: (i) recommended rates of N, P, and K for barley in Arizona, (ii) 10 t/ha of dried sewage sludge, and (iii) inorganic fertilizers to provide N, P, and K in amounts equal to those applied in the sewage sludge.

Barley genotypes evaluated for vegetative growth and grain yield responded similarly when fertilized with dried sewage sludge and inorganic fertilizers from commercial sources. Regardless of the fertilizer treatments, analysis of variance showed highly significant differences between genotypes. Fertilizer‐genotype interactions did not follow a uniform pattern to make a conclusive ranking of means. Results indicate that dried sewage sludge may be as valuable a fertilizer source as commercial fertilizers. Additional research using various sludge rates may be necessary to investigate the maximum fertilizer response potential of specific barley genotypes for the efficient use of sewage sludge in commercial barley production.
Alfalfa, Sweetcorn, and Wheat Responses to Long‐Term Application of Municipal Waste Water to Cropland
Authors: Campbell W. F. , Miller R. W. , Reynolds J. H. , Schreeg T. M.
Published: July 2010

The objective of this study was to assess, over two growing seasons, the long‐term effects of applying municipal waste water on agricultural land under semi‐arid conditions on selected crops. Alfalfa (Medicago sativa L.) cv Ranger, sweetcorn (Zea mays L.) cv Jubilee, and wheat (Triticum vulgare L.) cv Fremont, were grown on land to which waste water had been applied for > 15 y. Plants grown on effluent‐irrigated sites had greater growth rates, dry weights, and yields than did plants grown on irrigated control sites. Chemical analyses for metals in plant parts showed that Na was higher in plants growing on the waste water site, whereas Cu, Fe, and Zn were much higher in plants harvested on control sites. Metal concentrations observed in plant materials were below hazardous levels reported in the literature. In general, no significant, detrimental, long‐term effects of applying municipal waste water on land under semi‐arid conditions were detected. In fact, available P levels increased in effluent‐irrigated soils.
Elemental Contents of Plants Growing on Soil‐Covered Retorted Shale
Authors: Schwab A. P. , Lindsay W. L. , Smith P. J.
Published: July 2010

The concentrations of several potentially toxic elements (F, B, Mo, Pb, Ni, Co, Cd, Cr, Hg, Se, and As) were determined in plants growing on various depths of soil covering retorted (Paraho) shale. The plants that were sampled include: Indian ricegrass (Oryzopsis hymenoides), fourwing saltbush (Atriplex canescens), western wheatgrass (Agropyron smithii), Sherman's big bluegrass (Poa ampla), Utah sweetvetch (Hedysarum boreale), and winterfat (Ceratoides lanata). The F levels were elevated in some of the plants growing on 30 cm of soil over shale. The concentrations of Mo and the Cu/Mo ratios in the plants indicate that molybdenosis could be expected with livestock grazing on revegetated plants. Increasing the depth of soil cover reduced the Mo levels, but the second year's data indicate that increasing the soil depth may only temporarily reduce the potential molybdenosis problem. The plant levels of Pb, Co, Cd, and Hg were below analytical detection limits. The plant concentrations of Ni, As, Se, B, and Cd were too low to be of environmental concern.
Heavy Metals and Persistent Organics at a Sewage Sludge Disposal Site
Authors: Baxter J. C. , Aguilar M. , Brown K.
Published: July 2010

There are problems associated with the utilization of sewage sludge as an agricultural fertilizer. One of the more pressing problems is the question of heavy metals and persistent organics. There is concern that indiscriminate disposal of sewage sludges on agricultural lands may lead to decreased crop yields, and/or may endanger the human food chain through excessive accumulation of some of these metals in edible portions of crops.

The effects of sewage sludge disposal on agricultural land, and possible transmission of sludge contaminants into the food chain is a possible environmental problem. Soils, plants, and sewage sludge from the Metro Denver sewage sludge disposal site were examined for trace elements and persistent organics content. Concentrations of Zn, Cu, Ni, Cd, Pb, and Hg in soils increased when sludge was applied, whereas concentrations of As, Se, Mo, and 22 refractory organics were unaffected. Forage crops grown on these soils showed increased concentrations of Zn, Cu, Cd, and Ni; however, these metals were not elevated to a phytotoxic level or above ranges that would be considered normal for forage tissues. Concentrations of As, Se, and Hg in forage tissues were unchanged, while Pb concentrations decreased as a result of sludge applications. None of the forage tissues examined contained detectable levels of any of the 22 organics that they were analyzed for.

Soil metals (Zn, Cu, Ni, Cd, and Pb) extracted with DTPA (diethylenetriaminepentaacetic acid) did not correlate with plant concentrations of these metals. Results indicated that the DTPA soil test could be used as a reliable index as to the total metal concentration of a soil, but not as an indication of heavy metal availability for crop uptake.

Heavy metals and P remained within the depth of sludge incorporation. Nitrate concentrations, while decreasing with soil depth, showed that substantial amounts had leached to a 91‐cm depth.
Heavy Metals and Persistent Organics Content in Cattle Exposed to Sewage Sludge
Authors: Baxter J. C. , Johnson D. E. , Kienholz E. W.
Published: July 2010

Cattle grazing a sewage sludge disposal site were examined to determine whether, and to what extent, contamination of tissues had occurred as a result of exposure to sewage sludge. The heavy metal and persistent organics content of kidney, liver, muscle, and bone tissues from cattle grazing a sewage sludge disposal site were compared with tissues of cattle from a nearby control ranch. Tissues were analyzed for As, Cd, Cu, Hg, Mo, Ni, Pb, Se, Zn, and 22 persistent organics.

The sludge‐exposed cattle had an average kidney‐Cd content of 16 mg/kg (dry weight), which was significantly higher than the 4 mg/kg found in the control herd, but was not above a range that would be expected from older range cattle. There were no other tissue differences between the two groups with respect to Cd.

The average liver‐Cu concentration (4.6 mg/kg) of the sludge‐exposed cattle was significantly lower than that of the controls (19 mg/kg); however, both groups of animals displayed liver‐Cu concentrations that were considerably lower than levels previously considered normal. Mean kidney‐Hg and liver‐Se concentrations were significantly higher in the control cattle than in the sludge‐exposed cows. Kidney‐Zn concentrations of the sludge‐exposed cattle were significantly higher than those of the controls, but the magnitude of the differences was small. Differences between the two groups of animals in relation to Hg and Se were small, and it is doubtful that any real biological significance can be assigned to these differences.

Fat was the only tissue that contained detectable levels of 22 persistent organics. The only significant difference observed was alpha‐BHC (hexachlorocylohexane, alpha); the control herd averaged 30 µg/kg (wet weight), whereas the sludge‐exposed cattle averaged 10 µg/kg.
Hydrology and Soil Loss From a High‐Fertility, Rotational Pasture Program
Authors: Owens L. B. , Van Keuren R. W. , Edwards W. M.
Published: July 2010

Five small watersheds (0.25–3.1 ha) on sloping uplands in eastern Ohio were used to evaluate environmental effects of a beef management program of rotational summer grazing on one area, and rotational winter grazing/feeding with stored hay on another area. During the 5‐y study, annual precipitation was 1080 mm, which was 8–15% greater than the long‐term average. The surface runoff was measured by precalibrated H‐flumes, and automatically sampled using Coshocton wheels. Surface runoff from watersheds with beef cattle management increased, compared with the long‐term averages when hay was grown on the watersheds. Greater precipitation was the primary factor causing more runoff during the growing season (May–October), and the cattle management was a major contributing influence on the runoff increase during the dormant season (November–April). Maintenance of good vegetative cover on the study areas was a major factor in limiting annual average surface runoff to < 110 mm, which was a relatively small amount. The large runoff events, although a small percentage of the total number of events, produced most of the runoff volume. Soil loss from these pastures was minimal.
Plant Availability of Heavy Metals in a Sludge‐Treated Soil: I. Effect of Sewage Sludge and Soil pH on the Yield and Chemical Composition of Rape
Authors: Narwal R. P. , Singh B. R. , Panhwar A. R.
Published: July 2010

This study investigated the effects of sewage sludge and soil pH on yield and chemical composition, and heavy metal uptake of fodder rape (Brassica napus L. ‘Kenton’). Plants were grown in the greenhouse on a sandy soil amended with an anaerobically stabilized sewage sludge. Lime needs of the soil to attain pH levels of 5.6, 6.0, and 7.5 were determined in a separate incubation study. The rates of sewage sludge applied were 0, 50, and 100 t/ha on a dry weight basis. Application of sewage sludge in the incubation study decreased the soil pH, and consequently increased the lime needs of the soil. The soil pH also decreased with increasing period of incubation. Plants were harvested 5 weeks after germination, and again 5 weeks after the first harvest. For each harvest, the application of sludge increased the total dry matter yield of rape significantly at all pH levels. Maximum yields were obtained at pH 6.0. The concentrations of all measured macro‐nutrients generally increased with increased rate of sludge, but the concentrations were invariably lowest at pH 6.0.

The concentrations of Zn, Cd, and Ni in fodder rape generally increased, and those of Mn, Cu, and Co generally decreased with increased rate of sludge application. The pH level influenced the concentrations of the heavy metals studied, with the exception of Pb. The concentrations generally decreased when the pH increased. Although concentration of heavy metals was higher in the second harvest, in general, total amounts recovered were higher in the first harvest. The recovery of metals in rape, calculated as a percentage of 0.2N HCl‐extractable metals from the soil, decreased as the levels of sludge and soil pH increased.
Soda Ash Treatment of a Strontium‐90‐Contaminated Groundwater Seep
Authors: Spalding B. P. , Munro I. L.
Published: July 2010

A 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

Bean 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

Organochlorine 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

This 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.