bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ion Leaching in Forest Ecosystems along a Great Lakes Air Pollution Gradient
Authors: MacDonald N. W. , Burton A. J. , Liechty H. O. , Witter J. A. , Pregitzer K. S. , Mroz G. D. , Richter D. D. 
Published: July 2010

AbstractA gradient of H+, SO2−4, and NO−3 deposition across the Great Lakes region raised concerns over impacts on soil solution chemistry and ion leaching in regional forest ecosystems. Ten study sites representing northern hardwood and oak ecosystems were established across the gradient of increasing deposition from Minnesota to Ohio. Lysimeters were installed at lower E and lower B horizon boundaries at each site and sampled over a 2‐yr period. In soil solutions collected at lower E horizon boundaries, H+ and SO2−4 wet deposition were correlated with solution concentrations of SO2−4 r = 0.82** and 0.92**) and Mg2+ (r = 0.75** and 0.85**), and with the SO2−4/inorganic anion ratio (r = 0.71** and 0.70**). In soil solutions collected at lower B horizon boundaries, SO2−4 deposition was correlated with solution SO2−4 concentrations (r = 0.92**). Greater ionic outputs from B horizons than atmospheric inputs indicated that net losses of Ca2+ and Mg2+ were occurring from all sites. Sulfate outputs above background levels contributed 33 to 2367 molc SO2−4 ha−1 yr−1 from north to south along the gradient, equal to 3.7 to 71.7% of annual cation outputs. Excess H+ deposition accounted for 8 to 34% of annual cation outputs from north to south, and as much as 72% at one site with coarse‐textured soils. Elevated cation losses related to H+ and SO2−4 deposition indicate that cation depletion remains a plausible consequence of pollutant deposition to forest ecosystems with poorly buffered soils.
Photosynthesis and Nitrogen Fixation in Soybean Exposed to Nitrogen Dioxide and Carbon Dioxide
Authors: Gupta Gian , Li Yuncong , Sandhu Ravinder 
Published: July 2010

Abstract‘Williams‐82’ Soybean [Glycine max (L.) Merr.] plants, at the flowering stage, were exposed to NO2 (0.1 µmol mol−1, 7 h d−1) and CO2 (450 µmol mol−1, 12 h d−1) for 5 d singly and in combination in open‐top field chambers. The rate of photosynthesis (PN), specific root nodule nitrogenase activity (SNA), and leaf N were measured after exposure using the LICOR 6200 Portable Photosynthesis system, the acetylene‐ethylene reduction method, and the Kjeldahl digestion, respectively. The plants exposed to NO2 (with 350 µmol mol−1 CO2) showed significantly higher PN, SNA, and N compared with the control plants. The SNA and N were reduced, with no change in PN on exposing the plants to CO2 (in the absence of NO2). When the plants were exposed to a combination of these two gases, SNA was increased but the PN and N did not change. The stimulatory effect of NO2 was reduced by the inhibitory impact of CO2 on the parameters studied.
Physical and Chemical Properties of Coal Refuse from Southwest Virginia
Authors: Stewart B.R. , Daniels W.L. 
Published: July 2010

AbstractCoal refuse is difficult to reclaim due to high potential acidity, very coarse texture, low water retention, and fertility. This study was undertaken to determine the physical and chemical properties and the reclamation potential of samples from 27 coal refuse piles of varying age. Selected physical and chemical properties varied widely across this sample set. The >2 mm fragment content was 60%, and the average texture of the <2 mm fraction was a sandy loam with 15% clay. The mean water retention difference, (−1.50 to −0.030 MPa), on a whole sample basis was 0.08 kg water/kg refuse. The pH varied from 3.0 to 8.3 due to differences in the amounts and reactivity of pyritic minerals in refuse. Older piles generally had lower pH values than more recent piles. The saturated paste electrical conductivity (EC) was higher in the younger refuse due to active pyrite oxidation. A 5:1 water to soil (w/w) extract shows promise as an effective screen for samples with potentially high EC values. Coal refuse was generally low in available P and B. Total elemental analysis revealed that Si, Al, Fe, and K were the most abundant elements. The physical factor most limiting to plant growth is likely to be low water holding capacity, while low pH was found to be the chemical factor most limiting to plant survival. These findings indicate that some refuse piles may be suitable for direct seeding, but many will require heavy lime and/or organic treatments for successful reclamation.
Nitrate Dynamics in Riparian Forests: Groundwater Studies
Authors: Simmons Robert C. , Gold Arthur J. , Groffman Peter M. 
Published: July 2010

AbstractThis study was conducted to assess the removal of groundwater nitrate (NO−3) in different soil drainage classes within three riparian forests located in Rhode Island. A solution of NO−3 and a conservative tracer [either bromide (Br−) or chloride (Cl−)] was applied in the growing and the dormant seasons to trenches upgradient of wetland locations with hydric soils (poorly and very poorly drained soils) and transition zone locations with somewhat poorly and moderately well‐drained soils located immediately upslope of the wetlands. To assess removal, the change in groundwater concentrations of NO−3 relative to the concentration of the conservative tracer was observed in monitoring wells located in each soil drainage class from June 1989 through April 1990. Removal of groundwater NO−3 was consistently high in the wetland locations, generally in excess of 80% in both growing and dormant seasons. In the transition zones, attenuation was less than 36% during the growing season, and ranged from 50 to 78% in the dormant season. Attenuation in the transition zones was positively correlated with water table elevations. Transition zone attenuation was high in the dormant season relative to the growing season likely because high water tables during the dormant season caused the contaminant plume to be exposed to soil with higher organic matter. The results suggest that both wetlands and transition zones between wetlands and uplands can be important sinks for groundwater NO−3.
Low‐Contaminant Jarosite Waste as a Fertilizer Amendment
Authors: Kanabo I.A.K. , Gilkes R.J. 
Published: July 2010

AbstractLow‐contaminant jarosite (LCJ), with 1.1% N, 4.7% Zn, and 11% S, is a potential fertilizer source, but its use may create toxic conditions. This material was compared with standard fertilizers in glasshouse experiments and the effect of the application of jarosite to soils on the concentrations of heavy metals in plants was also investigated. On the basis of wheat (Triticum aestivum L.) yields, LCJ is about 5% as effective in supply N as NH4NO3. On the basis of Zn concentration in plant tops, LCJ was about 80% as effective as ZnSO4 in supplying Zn to wheat. Based on S concentrations in clover (Trifolium spp.) tops, LCJ was 30 and 60% as effective as CaSO4 in supplying S on light and heavy‐textured soils, respectively. Application of LCJ to soils resulted in elevated concentrations of Cd, Cu, and Zn in plant tissue. The increase in Cd concentration was such that it is unlikely that LCJ could be recommended as a fertilizer for plants grown for human or animal consumption.
Odor Control in Liquid Hog Manure by Added Amendments and Aeration
Authors: Al‐Kanani T. , Akochi E. , MacKenzie A. F. , Alli I. , Barrington S. 
Published: July 2010

AbstractA reduction in the emission of malodorous gases from liquid hog manure (LHM) would represent an advantage for LHM use in agricultural systems. Procedures for the reduction of disagreeable odors during storage of LHM (Sus scrofa domesticus) were studied in the laboratory. Sphagnum peat moss (Sphagnum moss species), 1.5 M H2SO4, 1.7 M H3PO4, monocalcium phosphate monohydrate (MCPM), elemental S, CaCO3, and CaO were used to reduce odors. Amended and nonamended LHM was incubated with and without aeration for periods ranging from 2 to 720 h at 23 ± 0.4°C. Odor measurements of emitted air were carried out using a sensory panel. Gas chromatography‐mass spectrometry (GC‐MS) was used to identify specific odor‐producing compounds. The GC‐MS analysis revealed that added Sphagnum moss (SM) prevented the release of 1,2‐ethanediamine, N‐methyl methanamine, 3‐methyl 2‐butanamine, methyl hydrazine, ethanethioic acid, and methanethiol from LHM. Aeration as a treatment, in general, resulted in a greater reduction of odor presence and offensiveness than nonaeration. In nonaerated LHM treatments, SM at levels of 4 or 8% (w/w) or a combined treatment of 2% CaCO3 plus 1% SM resulted in a significant reduction in odor presence and offensiveness. Little odor reduction was observed with H2SO4, H3PO4, MCPM, and CaO, and no odor reduction was found with elemental S.
Effect of Seeding on Thermophilic Composting of Tofu Refuse
Authors: Nakasaki Kiyohiko , Watanabe Atsushi , Kitano Makoto , Kubota Hiroshi 
Published: July 2010

AbstractDisposal of tofu processing residue is recently a serious problem in Japan. In this research, accelerated methods of composting tofu refuse were explored. The effect of seeding on the composting reaction rate of tofu refuse was examined by measuring changes in CO2 evolution, temperature, conversion of carbon, and microbial succession. The timing of CO2 evolution and microbial succession differed substantially when sterilized tofu refuse was seeded with two different inoculum sources. This difference was restricted only to early composting stages and the total amounts of CO2 evolved from both composts were similar in the later stage of refuse degradation. The analysis of microbial succession indicated that the types of microorganisms primarily responsible for composting of the refuse were the same in the later stages of both experiments. In contrast to the composting of sterilized tofu refuse, no measurable effect of seeding was observed when air‐dried tofu refuse was composted. Large numbers of microorganisms responsible for composting inhabited the air‐dried tofu refuse. Although the succession of thermophiles and patterns of CO2 evolution were different in composting sterilized and dried tofu refuses, no clear difference was observed in the final conversion of C of the raw refuse in all treatments.
Phosphorus Removal Processes in a Wetland after a Decade of Receiving a Sewage Effluent
Authors: Cooke James G. 
Published: July 2010

AbstractA study was made of the processes leading to phosphorus (P) removal in a wetland that received a high load of sewage‐P for over a decade. The amounts of P accounted for by sediment deposition, sorption to detrital material, and uptake by above ground biomass were compared with the mass of P entering and leaving the wetland system. Phosphorus deposition was shown to be the most important sink for P with rates of up to 30 g P m−2 d−1 being recorded. The pronounced spatial distribution of deposition as well as laboratory experiments indicated that P deposition occurred predominantly by reaction between sewage‐wetland waters (high in P, alkaline pH) and natural wetland waters (high in Fe and Al, acid pH) at or immediately below confluences joining their flow streams. Studies on P mass transport showed that the P removal rate (28–70%) was considerably greater than published values suggest could be predicted for this highly loaded (≃34 g P m−2 yr−1) system. It is suggested that the wetland configuration, whereby the flow from a relatively small area of sewage‐impacted wetland, is joined by waters from much larger unimpacted wetlands, is the reason for the relatively large P removal in this system. The relative magnitudes of P sinks in this study are different enough from other studies to suggest that the present level of P removal in this wetland is sustainable.
Prediction of Bioavailable Phosphorus Loss in Agricultural Runoff
Authors: Sharpley Andrew N. , Smith S.J. 
Published: July 2010

AbstractThe loss of bioavailable P (BAP) in both soluble (SP) and participate (BPP, bioavailable particulate P) forms in agricultural runoff, can accelerate the eutrophication of surface waters. Bioavailable P represents P that is potentially available for algal uptake. Although prediction of BAP loss would provide a more reliable assessment of the impact of agricultural management on surface water eutrophication than just SP or total P (TP), currently no predictive equations are available. Bioavailable P transport in soluble and particulate forms in runoff from 20 agricultural watersheds in the Southern Plains over a 5‐yr period, was predicted using kinetic and enrichment ratio approaches, respectively. Measured and predicted SP and BPP concentrations of individual runoff events were similar for all watersheds and management practices over a range of 7 to 3522 and 3 to 4059 µg L−1, respectively. Calculated as the sum of SP and BPP, BAP loss in runoff was predicted accurately, with only a 12% error in measured mean annual loss (662 g ha−1 yr−1). Although BAP loss below 100 g ha−1 yr−1 was underestimated, above this value measured and predicted values closely followed a 1:1 relationship. Inclusion of these equations in comprehensive water quality models will improve the prediction of agricultural management on the biological response of receiving water bodies.
Effects of Two Earthworm Species on Movement of Septic Tank Effluent through Soil Columns
Authors: Jones L.A. , Rutledge E.M. , Scott H.D. , Wolf D.C. , Teppen B.J. 
Published: July 2010

AbstractDevelopment of a clogging layer at the soil‐gravel interface often causes failure of septic tank filter fields to transmit effluent. A column study was undertaken to determine whether earthworms (Lumbricus terrestris L. and L. rubellus Hoff.), through their burrowing activity, could reverse the negative effects of clogging layer formation. Twelve soil columns, 0.20 m in diameter by 0.38 m long, were constructed using gravel and subsoil of a Peridge soil (fine‐silty, mixed, mesic Typic Paleudalf). The columns were dosed for at least 263 d with 2.3 cm d−1 of septic tank effluent until clogging layers had formed and stabilized. Steady‐state effluent flux densities through the columns ranged from 1.9 to 2.9 µm s−1, so that about 2 h were required for drainage of the daily effluent dose. The columns were divided into four groups based on their hydraulic performances, and the columns in each group were treated with 25 L. rubellus, 25 L. terrestris, or no worms. Within 80 d the flux densities through the columns containing earthworms increased to between 4.8 and 12.4 µm s−1, or 40 to 135% of the initial maxima before clogging layer formation. Effluent flux densities through control columns remained constant. Earthworm survival rates were not significantly different (P > 0.05) between species, with 81% of L. rubellus and 95% of l. terrestris surviving. In two columns, L. rubellus cocoons hatched. During the 96‐d study, the earthworms lost less than 4% of their initial weights on a dry weight basis. The L. rubellus and L. terrestris produced channels with median diameters of 2.3 and 8.4 mm, respectively.
Managing Soil Moisture on Waste Burial Sites in Arid Regions
Authors: Anderson J. E. , Nowak R. S. , Ratzlaff T. D. , Markham O. D. 
Published: July 2010

AbstractIn semiarid regions, where potential evapotranspiration greatly exceeds precipitation, it is theoretically possible to preclude water form reaching interred wastes by (i) providing a sufficient cap of soil to store precipitation that falls while plants are dormant and (ii) establishing sufficient plant cover to deplete soil moisture during the growing season, thereby emptying the water storage reservoir of the soil. Here we discuss the theory and rationale for such an approach and then present the results of a field study to test its efficacy at the Idaho National Engineering Laboratory (INEL). We examined the capacity of four species of perennial plants to deplete soil moisture on simulated waste trenches and determined the effective water storage capacity of the soil. Those data enabled us to estimate the minimum depth of fill soil required to prevent deep drainage. Any of the species studied can use all of the plant‐available soil water, even during a very wet growing season. The water storage capacity of the soil studied is 17% by volume, so a trench cap of 1.6 m of soil should be adequate to store precipitation received at the INEL while plants are dormant. We recommend a fill soil depth of 2 m to provide a margin of safety in case water accumulates in local areas as a result of heavy snow accumulation, subsidence, or runoff. Fill soil requirements and choice of plant species will vary, but the concepts and general approach are applicable to other shallow land burial sites in arid or semiarid regions.
Atmosphere × Canopy Interactions of Nitric Acid Vapor in Loblolly Pine Grown in Open‐Top Chambers
Authors: Taylor G. E. , Owens J. G. , Grizzard T. , Selvidge W. J. 
Published: July 2010

AbstractMany studies that address the impact of tropospheric O3 on agricultural and forested ecosystems utilize the open‐top chamber. During the production of O3 using electrical discharge generators fed with dry air, there is an inadvertent addition of HNO3 vapor, a highly reactive trace gas. While several studies have proposed that HNO3 vapor introduces artifacts, none has measured concentrations of the odd‐N2 trace gas in the chamber or investigated the fate of the N in the context of whole‐plant physiology and growth. These questions were investigated using open‐top chambers containing seedlings of loblolly pine (Pinus taeda L.) during the 1988 growing season in Oak Ridge, TN. The O3 treatments consisted of charcoal‐filtered or subambient (0.96 µmol m−3, 24‐h mean), ambient (1.62 µmol m−3, 24‐h mean), and elevated (2.36 µmol m−3, 24‐h mean) concentrations, the last being accomplished by proportional O3 addition over the diurnal period. Measurements of the HNO3 vapor concentration during dry periods only (no rainfall or ground‐level fog) averaged 28.6 nmol m−3 (subambient), 55.4 nmol m−3 (ambient air), and 240.0 nmol m−3 (elevated O3), an 8.4‐fold range. For every 100 mol of O3 added to the chamber, 28 mol of HNO3 vapor were inadvertently added; this ratio is several times higher than that previously reported. This result, taken with published estimates of leaf conductance to HNO3 vapor, indicates a maximum N deposition in the form of HNO3 vapor ranging from 19.5 pmol N cm−2 leaf area h−1 (subambient O3) to 171.9 pmol N cm−2 h−1 (elevated O3). Given the nutrient content of the seedlings and knowledge of the fate of HNO3 vapor on the leaf surface and leaf interior, the degree to which N deposition via HNO3 vapor met the N requirements of the loblolly pine seedlings was estimated. Seedlings in the elevated O3 treatment had an upper‐limit estimate of 3.5% for the needles and 1.8% for the whole plant of N derived from HNO3 vapor. The concentration of HNO3 vapor in the chambers, site of HNO3 vapor deposition, N requirements of the loblolly pine seedlings, and estimated threshold for phytotoxic effects of HNO3 vapor indicate that the inadvertent production of this odd‐N2 trace gas is important in understanding the atmospheric chemistry within the chambers, but that the level of N loading in this study is unlikely to affect physiology or growth. However, we recommend that studies that employ higher O3‐exposure scenarios recognize the potential for inadvertent N deposition, particularly in trees grown in N‐deficient substrate.
Atmospheric Transport of Organophosphate Pesticides from California's Central Valley to the Sierra Nevada Mountains
Authors: Zabik John M. , Seiber James N. 
Published: July 2010

AbstractAtmospheric transport of organophosphate pesticides from California's Central Valley to the Sierra Nevada mountains was assessed by collecting air‐ and wet‐deposition samples during December, January, February, and March, 1990 to 1991. Large‐scale spraying of these pesticides occurs during December and January to control insect infestations in valley orchards. Sampling sites were placed at 114‐ (base of the foothills), 533‐, and 1920‐m elevations. Samples acquired at these sites contained chlorpyrifos [phosphorothioic acid; 0,0‐diethyl 0‐(3,5,6‐trichloro‐2‐pyridinyl) ester], parathion [phosphorothioic acid, 0‐0‐diethylo‐(4‐nitrophenyl) ester], diazinon {phosphorothioic acid, 0,0‐diethyl 0‐[6‐methyl‐2‐(1‐methylethyl)‐4‐pyrimidinyl] ester} diazinonoxon {phosphoric acid, 0,0‐diethyl 0‐[6‐methyl‐2‐(1‐methylethyl)‐4‐pyrimidinyl] ester}, and paraoxon [phosphoric acid, 0,0‐diethyl 0‐(4‐nitrophenyl) ester] in both air and wet deposition samples. Air concentrations of chloropyrifos, diazinon and parathion ranged from 13 to 13 000 pg/m3 at the base of the foothills. At 533‐m air concentrations were below the limit of quantification (1.4 pg/m3) to 83 pg/m3 and at 1920 m concentrations were below the limit of quantification. Concentrations in wet deposition varied with distance and elevation from the Central Valley. Rainwater concentrations at the base of the foot hills ranged from 16 to 7600 pg/mL. At 533‐m rain and snow water concentrations ranged from below the limit of quantification (1.3 pg/mL) to 140 pg/mL and at 1920 m concentrations ranged from below the limit of quantification to 48 pg/mL. These findings indicate that atmospheric transport of pesticides applied in the valley to the Sierra Nevada mountains is occurring, but the levels decrease as distance and elevation increase from the valley floor.
Pore Water Chemistry of Phosphogypsum‐Treated Soil
Authors: Luther S.M. , Dudas M.J. 
Published: July 2010

AbstractPhosphogypsum (PG) is a gypsum‐based by‐product of phosphate fertilizer production and is commonly stored at plant sites. As stockpiles of the material accumulate worldwide, elemental leaching from repositories is of potential environmental concern. In this study, samples of glacial till, PG, and mixtures of the two were incubated with deionized water. Solution extracts were analyzed for chemical constituents. Speciated activities of Al, Cr, and Cu, obtained using GEOCHEM, were related to theoretical levels estimated from solubility constants of potential solubility‐controlling solids. Maximum pore water levels of As, B, Ca, Fe, K, Mn, Na, NH+4‐N, NO−3‐N, Ni, P, Se, Si, Sr, V, and Zn were less when PG was mixed with soil and allowed to equilibrate. However, only the concentrations of Cd, Fe, Ni, P, Sr, V, and Zn were less by close to an order of magnitude or more. The increase in pH with soil addition influenced these substantial changes in elemental concentrations. The activities of Cr and Cu species decreased with soil addition, but the suspensions were considerably undersaturated relative to potential solubility‐controlling solids. GEOCHEM indicated Al activities were in equilibrium with alunite, basaluminite, gibbsite, and jurbanite. As PG was neutralized through the addition of calcareous glacial till, solution levels of Al, Cd, Cr, Cu, Fe, Ni, P, Sr, V, and Zn all decreased substantially.