bluuebunny/crossref_metadata_2025_split huggingface dataset:
Physical Properties of Minesoils in West Virginia and Their Influence on Wastewater Treatment
Authors: Skousen J. , Sencindiver J. , Owens K. , Hoover S. 
Published: July 2010

AbstractWastewater treatment in southern West Virginia is limited by steep terrain and shallow soil. Surface mine reclamation replaces soil materials that may be suitable for wastewater treatment. Two minesoil series, Kaymine (a loamy‐skeletal, mixed, nonacid, mesic Typic Udorthent) and Sewell (a loamy‐skeletal, mixed, acid, mesic Typic Udorthent), were selected and soil samples were collected on six reclaimed surface mines to determine texture, bulk density, water retention, and saturated hydraulic conductivity (Ksat). Kaymine had more clay and silt and higher moisture retention than Sewell. In A horizons, Kaymine Ksat was about two orders of magnitude faster than Sewell, but Ksat values were highly variable within and among sites. On two reclaimed mine sites (one Sewell and one Kaymine), tapwater or wastewater was surface applied to 9 m2 field plots over 32 wk. Leachate was collected in 50 and 100 cm wells and analyzed for chemical and microbiological properties. On the Sewell minesoil, little water was collected in wells after application, therefore water failed to move adequately in this minesoil. On Kaymine, Fe, Mn, sulfate, and suspended solids were present in all wells, indicating flushing of these materials from minesoils into wells. Nitrate (NO3)‐N was about two times greater in wastewater than tapwater and this same ratio was found in corresponding wells. Biological oxygen demand was decreased by 87% from wastewater to water in wells. Fecal coliform bacteria were not removed by wastewater passing through Kaymine soils. In general, these minesoils are not suitable for wastewater renovation based on the application methods and rates employed in this study.
Nitrate Removal from Groundwater Using a Denitrification Wall Amended with Sawdust: Field Trial
Authors: Schipper Louis , Vojvodić‐Vuković M. 
Published: July 2010

AbstractNitrate (NO3) contamination of groundwater can cause pollution of receiving waters. We examined the mechanisms by which a “denitrification wall” removed NO3 from shallow groundwater. The denitrification wall was constructed by digging a trench (35 m long, 1.5 m deep, and 1.5 m wide) that intercepted groundwater. The excavated soil was mixed with sawdust (30% v/v) as a C source then returned to the trench. We assessed NO3 removal and denitrification in the wall for 1 yr. Incoming concentrations of NO3 in groundwater ranged from 5 to 16 mg of N L−1 but these decreased to <2 mg N L−1 in the denitrification wall. Total N in the wall declined during the year demonstrating that N immobilization was not a large sink for NO3. Denitrifying enzyme activity (DEA) reached a maximum of 906 ng of N g−1 h−1 after 6 mo of operation, indicating that denitrification was an important mechanism for NO3 removal. We calculated a maximum rate of NO3 removal by denitrification of 3.6 g N m−3 d−1. Substrate‐amendment experiments showed that denitrification in the wall was primarily limited by NO3 concentration and not C. During the study there was no significant decrease (P < 0.05) in total C but the availability of the remaining C declined. Despite this decrease, the DEA and microbial biomass were stable during the last 6 mo. This study demonstrated that denitrification walls can effectively remove NO3 from groundwater thereby protecting receiving waters.
Nitrous Oxide Emission in Three Years as Affected by Tillage, Corn‐Soybean‐Alfalfa Rotations, and Nitrogen Fertilization
Authors: MacKenzie A. F. , Fan M. X. , Cadrin F. 
Published: July 2010

AbstractNitrous oxide (N2O) produced from agricultural activities must be determined if management procedures to reduce emissions are to be established. From 1994 to 1996, N2O emissions were determined using a closed chamber technique. Continuous corn (Zea mays L.) at four N rates of 0, 170, 285, and 400 kg of N ha−1 was used on a Ste. Rosalie heavy clay (a very‐fine‐silty, mixed, nonacid, frigid Typic Humaquept) and a Chicot sandy loam (a fine‐loamy, frigid, Typic Hapludalf). On two additional sites, a Ste. Rosalie clay and an Ormstown silty clay loam (a fine‐silty, mixed, nonacid, frigid Humaquept) no‐till (NT) and conventional tillage (CT); monocultural corn (CCC), monocultural soybean (Glycine max L.) (SSS); corn‐soybean (SSC, CCS); and soybean‐corn‐alfalfa (Medicago sativa L.) phased rotations (SAC, CSA, and ACS) were used. Nitrogen rates of 0, 90, and 180 kg of N ha−1 for corn and 0, 20, and 40 kg of N ha−1 for SSS were used. Rates of N2O emission were measured from April to November in 1994 and 1995, and from mid‐March to mid‐November in 1996. Maximum N2O emissions reached from 120 to 450 ng of N m−2 s−1 at the Ormstown site to 50 to 240 ng of N m−2 s−1 at the Ste. Rosalie soil. Generally, N2O emissions were higher in the NT systems, with corn, and increased linearly with increasing N rates, and amounted to 1.0 to 1.6% of fertilizer N applied. The N2O emission rates were significantly related to soil denitrification rates, water‐filled pore space, and soil NH4 and NO3 concentrations. A corn system using conventional tillage, legumes in rotation, and reduced N fertilizer would decrease N2O emission from agricultural fields.
The Influence of Planting and Soil Characteristics on Mineralization of 2,4,5‐T in Rhizosphere Soil
Authors: Boyle Jay J. , Shann Jodi R. 
Published: July 2010

AbstractPhytoremediation is a potential means of addressing soil contamination. It is not understood, however, what limits or fosters the degradation of xenobiotics in planted soil. This study examined the relative influence of plant species and soil type on biodegradation in the rhizosphere. In a complete design, three plant species (sunflower, Timothy grass, and red clover) were grown in three field‐collected soils (Jules silt loam [a coarse‐silty, mixed (calcareous), mesic Typic Udifluvent]; Miamian clay loam [a fine, mixed, mesic Typic Hapludalf]; Parke silt loam [a fine‐silty, mixed, mesic Ultic Hapludalf]). Soil characteristics and microbial activity, biomass, and mineralization of 2,4,5‐trichlorophenoxyacetic acid (2,4,5‐T), were determined in soil before and after planting. In general, the characteristics of an unplanted soil were correlated to its microbial biomass and activity. Not suprisingly then, soil type was the most significant determinant of xenobiotic degradation in both planted and unplanted systems. In spite of this strong soil effect, planting always resulted in a significant increase in 2,4,5‐T mineralization. The magnitude of this effect varied with soil. The soil initially low in organic matter, K, and P, appeared to gain the most from being planted. The plant species used produced a minor effect, but resulted in significant (mineralization) differences only in higher fertility soils.
Plant Biomass and Elemental Changes in Shrubland Forages following Biosolids Application
Authors: Pierce B.L. , Redente E.F. , Barbarick K. A. , Brobst R.B. , Hegeman P. 
Published: July 2010

AbstractLand application of biosolids is a viable management practice for agriculture, but minimal information exists on beneficial uses for native rangeland. This study was conducted to determine the effect of surface‐applied biosolids on the canopy cover, aboveground biomass, and nutrient status of native plant species in a sagebrush (Artemisia spp.) community in western Colorado. Biosolids were applied once in 1991 at nine rates consisting of 0, 5, 10, 15, 20, 25, 30, 35, and 40 Mg ha−1 to plots measuring 3320 m2. Biosolids application increased the biomass of perennial grasses up to 300% at 25 Mg ha−1 treatment rates in 1993. We also found 60 to 70% increases in plant tissue N concentrations in western wheatgrass (Agropyron smithii Rydb.), bluebunch wheatgrass [A. spicatum (Pursch) Scribn. & Smith], and Indian ricegrass [Oryzopsis hymenoides (R. & S.) Ricker]. The quality of grass forage was also improved through a change in the Cu/Mo ratios. Before biosolids application, the three grasses noted above had Cu/Mo ratios below 1.2/1, which is known to cause Mo‐induced Cu deficiencies in cattle (Bovis abortus), sheep (Ovis aries), and some wild ruminants. Biosolids treatment increased the Cu/Mo ratio above 2/1 for western wheatgrass and bluebunch wheatgrass 1 yr after application at low rates and 2 yr after amendment at intermediate application rates. The Cu/Mo ratio of Indian ricegrass also increased above 2/1 2 yr after surface application at intermediate biosolids application rates. Forage quantity and nutritional value of some native grasses was improved for livestock and wildlife consumption with biosolids application.
Humic‐Acid Transformation during Composting of Municipal Solid Waste
Authors: Chefetz Benny , Adani Fabrizio , Genevini Pierluigi , Tambone Fulvia , Hadar Yitzhak , Chen Yona 
Published: July 2010

AbstractComposting of municipal solid waste (MSW) was studied in an attempt to characterize concomitant transformations of humic acid (HA). Humic acid and Core‐HA were extracted from MSW at various stages during composting using the following methods: (i) The common IHSS method (HA); and (ii) performing organic solvent and sulfuric acid extractions prior to the alkaline extraction (Core‐HA). Mass balance was calculated for each compost sample during composting, and cross polarization magic angle spinning (CPMAS) 13C‐NMR and fourier transform infrared (FTIR) spectroscopy measurements were employed on the purified HAs and Core‐HAs. The absolute level of HA decreased during composting by 50% whereas the level of Core‐HA was steady throughout the process. The 13C‐NMR and FTIR spectra of the HAs indicated a high rate of change in structure during composting. The aromatic and phenolic C‐containing groups increased by 23 and 16%, respectively. In contrast, the Core‐HA spectra were stable, with only minor changes recorded during composting. The “coating” materials (polysaccharides, peptides, and lipids) bonding to the “core” HA structure degraded during composting, resulting in HA structures of higher aromaticity. The FTIR spectra of both HA and Core‐HA exhibited minor peaks in the carboxyl C, and the high rate of aliphatic C‐containing groups recorded from the 13C‐NMR spectra resembled “young” (type III) humified materials from soils. The mass‐balance data, together with the spectroscopic analyses indicate that one of the major HA transformation processes occurring events during the process is the degradation of the coating materials, yielding the core HA structure.
Extractable Trace Elements in the Soil Profile after Years of Biosolids Application
Authors: Barbarick K. A. , Ippolito J. A. , Westfall D. G. 
Published: July 2010

AbstractThe U.S. Environmental Protection Agency (USEPA) and some state agencies regulate trace element additions to soil from land application of biosolids. We generally consider trace elements added in biosolids (sewage sludge) to accumulate in the soil surface without significant transport below the plow layer. We used 11 yr of field‐study information from biosolids addition to dryland hard red winter wheat (Triticum aestivum L. “Vona” or “TAM107”) to determine the distribution of NH4HCO3 diethylenetriaminepentaacetic acid (AB‐DTPA)‐extractable Cd, Cr, Cu, Mo, Ni, Pb, and Zn in 0 to 20 (plow layer), 20 to 60, 60 to 100, and 100 to 150 cm depth increments. This study is unique since it involves multiple biosolids application in a dryland summer fallow agroecosystem. We applied five or six applications of biosolids from the cities of Littleton and Englewood, CO, to Weld loam (a fine, montmorillonitic, mesic Aridic Paleustoll) or Platner loam (a fine, montmorillonitic, mesic Aridic Paleustoll) at four locations. This paper focuses on the 0 (control), the 56 or 67 kg of N ha−1 fertilizer rates, and the 6.7 and 26.8 dry Mg of biosolids ha−1 rates that we added every crop year. We observed significant (P < 0.10) accumulations of the trace elements in the plow layer of the biosolids‐amended soils. Only Zn showed consistent increases in extractable levels below the plow layer at all four sites. The biosolids Zn concentration (average of ∼1300 mg kg−1) was larger than any other trace element resulting in larger loading of this element.
Analysis of Metal‐EDTA Complexes by Electrospray Mass Spectrometry
Authors: Baron Dirk , Hering Janet G. 
Published: July 2010

AbstractSolutions of the strong complexing agent ethylenediaminetetraacetic acid (EDTA) and Cu, Pb, Cd, Al, and Fe(III) were examined by electrospray mass spectrometry (ES/MS). Uncomplexed EDTA and metal‐EDTA complexes survive the electrospray process intact and can be detected simultaneously by mass spectrometry. Best sensitivity was achieved in the positive ion mode in which EDTA and EDTA‐metal complexes (present in solution as anions) were detected as protonated species with a single positive charge. Except for the protonation, the aqueous metal‐EDTA complexes are preserved and neither fragmentation of complexes nor formation of clusters with more than one metal or ligand were observed in the mass spectra. Detection limits are between approximately 1 to 2 µM for uncomplexed EDTA and for the Cu‐EDTA and Pb‐EDTA complexes, with a linear range up to 10−4 M. Calibrations based on solutions with equimolar concentrations of EDTA and Cu or Pb can be used to quantify EDTA‐metal complexes in solutions with excess EDTA or metal, and in solutions with more than one metal present. Isotopic signatures of metals in the metal‐ligand complexes are preserved, allowing the identification of the metal in a metal‐ligand complex. Isotopic signatures of metals can therefore aid in the identification of metal‐ligand complexes in unknown samples.
Ponderosa Pine Tree Rings as Historical Monitors of Zinc and Cadmium Pollution
Authors: Schaumloffel John C. , Filby Royston H. , Moore Barry C. 
Published: July 2010

AbstractConcentrations of Zn and Cd were determined in growth rings of 13 ponderosa pines (Pinus ponderosa Dougl.) from two watersheds impacted by the discharge of heavy‐metal laden waste. Trees growing along rivers with contaminated sediments have greater concentrations of Zn and Cd than trees growing at uncontaminated reference sites. Concentrations of Zn and Cd in trees from the Coeur d'Alene region (Idaho, USA) decline progressively in younger growth rings. This indicates that reductions in mining activity and implementation of pollution control technologies have reduced Zn and Cd loading in this system. Samples from the Coeur d'Alene region contain Zn and Cd concentrations greater than those found trees from contaminated sites in the Lake Roosevelt (Washington, USA) region. Clearly, the effects of soil and other environmental conditions cannot be accounted for over the past 60 yr. However, dendrochemical analyses suggest that heavy‐metal sulfide wastes in the Coeur d'Alene region have a greater susceptibility to mobilization than siliceous slag wastes in Lake Roosevelt. Concentrations of Zn and Cd measured in a tree growing along an intervening river suggest that Zn and Cd from the Coeur d'Alene basin are diluted before reaching Lake Roosevelt. Radial translocation of Zn and Cd to the heartwood cannot be excluded as a possible influence on elemental distribution of Zn and Cd in ponderosa pine. Nonetheless, the data demonstrates that ponderosa pine can effectively integrate mobile Zn and Cd present in their environment during wood formation.
Groundwater Quality under Conventional and No Tillage: I. Nitrate, Electrical Conductivity, and pH
Authors: Patni N. K. , Masse L. , Jui P. Y. 
Published: July 2010

AbstractThe use of conservation tillage is increasing in North America, but information on its effect on water quality in cold climatic regions is limited. To obtain such information, the effect of no‐tillage (NT) and conventional tillage (CT) treatments on nitrate‐nitrogen (NO3‐N) concentration, specific electrical conductivity (EC), and pH in shallow groundwater (1.2, 1.8, 3.0, and 4.6 m depths) was studied over four successive crop years in corn fields (loam soil) of approximately 3 ha each, located in eastern Ontario. Water table elevation was also monitored during three crop years. Average NO3‐N concentration at the 1.2, 1.8, and 4.6 m depths was consistently higher under CT than under NT in every crop year and every season. However, the effect of tillage was not significant at P < 0.05. Nitrate concentration decreased significantly with depth. It was about two to three times the drinking water limit of 10 mg/L as NO3‐N at the 1.2, 1.8, and 3.0 m depths. At the 4.6 m depth, NO3‐N concentrations were mostly low but increased with time. Changes in water table elevation appeared to affect NO3‐N concentrations at the 1.2 m depth under NT only. At a given depth, EC and pH of groundwater were not affected by tillage treatment. However, within each tillage treatment, values increased significantly with depth. Results from this study indicated a large spatial variability in NO3‐N and EC values in groundwater, which could have masked small tillage effects. More intensive temporal and spatial sampling may be required to establish tillage treatment effects, if any.
Spatial and Temporal Variability of Phosphorus Retention in a Riparian Forest Soil
Authors: Lyons Jodi B. , Görres Josef H. , Amador José A. 
Published: July 2010

AbstractRiparian zones remove P from surface runoff and can act as filters of nonpoint source (NPS) P pollution for surface waters. Riparian forest soils were investigated in spring and fall for their capacity to retain PO3−4‐P. Samples (300 on each date) were taken from a soil drainage catena from moderately well (MWD), somewhat poorly (SPD), and poorly drained (PD) soil in May and November of 1995 to examine spatial and temporal variability of P retention and its relationship to soil properties. The equilibrium P concentration at zero sorption (EPC0) was determined for each sampling point (lower EPC0, = higher P retention capacity). Mean (coefficient of variation, CV) EPC0 values were 3.8 (0.49) mg P L−1 in May and no P sorption was apparent in November for SPD soil, 1.0 (1.34) and 1.5 (1.03) P L−1 in May and November, respectively for MWD soil, and 0.5 (1.87) and 1.3 (1.13) mg P L−1, respectively for PD soil. The EPC0 was significantly and positively correlated to organic matter (OM) for all drainage classes on both dates. Low EPC0 values—high P retention capacity—in MWD and PD soil corresponded with high Feox and Alox values. For SPD soil, high mean EPC0 corresponded with low mean Feox and Alox values. The relationship between EPC0 and Feox and Alox was described by a hyperbolic function for MWD and PD soil, but not for SPD soil. The EPC0 did not exhibit spatial structure at the sampling scale used for any of the drainage classes, even though Feox, Alox, and OM content showed spatial structure.
Kinetics and Modeling of Dissolved Phosphorus Export from a Tile‐Drained Agricultural Watershed
Authors: Xue Yuan , David Mark B. , Gentry Lowell E. , Kovacic David A. 
Published: July 2010

AbstractAgricultural runoff can be a source of P, a limiting factor for freshwater eutrophication. To develop a simple method to estimate P export from the cropland, we studied 1.2‐µm filtered dissolved phosphorus (DP) output from four tiles draining areas ranging from 8 to 25 ha, and from a river draining a 48 173 ha watershed in east‐central Illinois during 1993 to 1996. The land was under maize (Zea mays L.)‐soybean (Glycine max L.) rotation. The tiles were estimated to contribute more than 86% of the river flow and 65 to 69% of the river DP export during 1995 to 1996. The DP load from tiles followed consecutive pseudo first‐order kinetics in terms of tile flow (DP load depended on the amount of DP remaining in the soil matrix). The kinetic curves indicated a soluble‐inorganic‐P pool that was quickly depleted and replenished. In contrast, for DP export from the river at the watershed scale we observed pseudo zero‐order kinetics based on river flow (DP export was independent of how much DP remained in the watershed). The contribution from numerous tiles and surface runoff to the river may have stabilized DP export at the watershed scale and therefore could explain the different kinetic orders. For the study watershed, a one parameter equation could estimate watershed‐wide DP export: k′ × (surface water discharge from the watershed) × (watershed area), with k′ being 3.94 × 10−6 mg P L−1 ha−1. Our approach should be tested in watersheds with different geographic and agricultural characteristics.
Decomposition of Blackberry and Broomsedge Bluestem as Influenced by Ozone
Authors: Kim J.S. , Chappelka A. H. , Miller‐Goodman M. S. 
Published: July 2010

AbstractMany researchers have reported on individual plant responses to O3, but few have investigated the effects of this pollutant on ecosystem function. Our investigation examined the influence of O3 on short‐term (Phase I) litter decomposition of blackberry (Rubus cuneifolus Pursh.) and broomsedge bluestem (Andropogon virginicus L.), two plant species native to early successional forest communities in the southern USA. Mixed blackberry/broomsedge litter (1:1) collected from plants exposed to different levels of O3 for one growing season was placed in open‐top chambers and exposed to different O3 levels of treatments for 24 wk. Litter also was incubated in microcosms in the laboratory at 25 or 30°C to determine the effects of climate change on O3‐treated litter. Initial C and N concentrations of the collected foliage did not differ significantly among treatments for either species. Blackberry litter had approximately twice as much N as broomsedge, and when collected from 2X O3 chambers, had significantly greater permanganate lignin than the other treatments. Initial permanganate lignin concentration of blackberry, over all O3 treatments, correlated significantly with remaining mass of the litter mixture after 24 wk exposure. Litter decomposed more slowly in the 2X chambers than in the other treatment chambers, regardless of litter source. Elevated O3‐exposed litter (2X) decomposed the slowest regardless of treatment applied. There were significant temperature and time effects observed with litter decomposition; litter incubated at 30°C decomposed faster than at 25°C. Our data suggest O3 may influence substrate quality and microbial activity, thus reducing the rate of litter decomposition in early successional forest communities.