bluuebunny/crossref_metadata_2025_split huggingface dataset:
Release of Aluminum following Whole‐Tree Harvesting at the Hubbard Brook Experimental Forest, New Hampshire
Authors: Lawrence G. B. , Fuller R. D. , Driscoll C. T. 
Published: July 2010

AbstractFrom fall, 1983, through spring, 1984, an experimental watershed at the Hubbard Brook Experimental Forest in New Hampshire was commercially whole‐tree harvested. Stream chemistry was monitored along an elevational gradient for approximately 1 yr prior to and 2 yr following the treatment in both the experimental watershed and an adjacent reference watershed. Whole‐tree harvesting initially resulted in a large increase in stream NO−3 and basic cation (Ca2+, Mg2+, Na+, and K+) concentrations and a decrease in stream sulfate concentrations. A decrease in pH and increase in Al concentrations followed. Elevational trends in stream chemistry were qualitatively similar before and after the cut, although the absolute concentrations of solutes changed markedly. These responses are explained by increased soil nitrification coupled with decreased vegetative uptake following the whole‐tree harvest. Acidity generated by nitrification facilitated the mobilization of basic cations and increased anion adsorption. When NO−3 production exceeded the release of basic cations, stream pH declined and Al concentrations increased. Aluminum was released in an entirely inorganic form resulting in potentially toxic concentrations in streamwater.
Soil Properties, Irrigation Water Quality, and Soil Moisture Level Influences on the Movement of Nickel in Sewage Sludge‐Treated Soils
Authors: Welch J. E. , Lund L. J. 
Published: July 2010

AbstractA column study was conducted to assess the effects of soil properties, irrigation water quality, and soil moisture level on the movement of Ni in sewage sludge‐treated soils. Surface layer samples of six soil series were packed into 24 columns, 10.2 cm in diameter and 110 cm in length. An air‐dried, anaerobically digested sewage slude was mixed into the top 15 cm of soil at a rate of 300 Mg ha−1. The columns were maintained at moisture levels of saturation and unsaturation (16.7 kPa tension) and leached with two waters of different quality. The unsaturated columns were irrigated about every 12 d with 5.08 cm of water for 13 months. The saturated columns were leached for 7 months. At the termination of the experiment the columns were cut open and the soil sectioned into 3‐cm intervals the entire length of each column. Samples were extracted with water and 4 M HNO3 and analyzed for chemical constituents. Irrigation water quality did not affect the amount of Ni leached from the sludge‐amended soil layer nor the depth of Ni movement. Mass balance calculations showed that an average of 3.3% of sludge‐applied Ni leached from the sludge‐amended soil layer of the saturated columns compared to 10.7% for the unsaturated columns. An average of 96.7% of sludge‐applied Ni remained in the sludge‐amended soil layer of the saturated columns compared to 89.3% for the unsaturated columns. For the saturated columns an average of 74.9% of sludge‐applied Ni leached from the sludge‐amended soil layer was accumulated in the 0‐ to 3‐cm soil interval compared to 46.5% for the unsaturated columns. Nickel movement below the sludge‐amended soil layer for the saturated columns ranged from 3 to 15 cm with an average of 9 cm compared to a range of 3 to 45 cm and an average of 18 cm for the unsaturated columns. Correlation and regression analysis indicated that pH and soil texture were the soil properties that best predicted the depth of Ni movement.
Phytoavailability of Boron from Organic Sources
Authors: Burkman W. G. , Adriano D. C. , Afre J. L. 
Published: July 2010

AbstractExperiments were conducted to determine the use of certain organoborates as potential sources of B for plant nutrition and to assess the sensitivity to them by different crop species. Of particular interest was sodium tetraphenylboron (NaTPB), a specific precipitant for radiocesium. For comparison, the inorganic source of B, boric acid (BA), was used as the control source of B. Greenhouse experiments indicated the following: (i) BA and NaTPB produced similar toxicity symptoms in the various crops studied; (ii) the order of sensitivity to NaTPB for various species followed the usual order for B toxicity, i.e., members of the bean (Phaseolus spp.) family are most sensitive, whereas cereals and chard (Beta vulgaris L.) were least sensitive; (iii) crop dry matter yields can best be predicted by the applied soil B on a coarse‐textured soil than by the plant B concentration; and (iv) at the same B level added to soil, NaTPB was more deleterious to plant growth than BA. A germination study indicated that at equal levels of B in substrate solution, the organo‐borates, NaTPB, and diphenylboric acid were more injurious than BA to root and shoot growths, providing more conclusive evidence that the organic constituents of these compounds are also phytotoxic.
Effects of Simulated Acid Rain on Yield Response of Two Soybean Cultivars
Authors: Porter P. M. , Banwart W. L. , Hassett J. J. , Finke R. L. 
Published: July 2010

AbstractAn important component of the effects of acid rain on our ecosystem is its impact on the yield of agricultural crops. Field experiments were conducted for 3 yr to determine the effects of simulated acid rain on seed yield of two soybean [Glycine max (L.) Merr.] cultivars, ‘Amsoy 71’ and ‘Williams 82’. Soybeans were grown on a Flanagan silt loam (fine, montmorillonitic, mesic Aquic Argiudoll) and protected from ambient rainfall by movable rain exlusion shelters. Plants were treated biweekly with simulated rain of pH 5.6, 4.6, 4.2, 3.8, 3.4, and 3.0. For Amsoy 71 there was a linear decrease in yield with increasing rainfall acidity for 1 of 3 yr but no significant effects for the other two. Thus acid rain appears to reduce the yield of some soybean cultivars slightly but this effect is not consistent from year to year. Amsoy 71 and Williams 82 soybean treated with the most acidic rain, pH 3.0, resulted in average yields for the 3 yr of the study of approximately 3 and 4% lower than the average yields for the other treatments, respectively. However, calculations from the response functions developed have shown that at current levels of rainfall acidities the effects on yield are very small. With an increase in rainfall acidity of 50% in Illinois the predicted yield decrease for Amsoy 71 and Williams 82 soybean would be less than 1%. Similarly the expected increase in yield of these cultivars would be 1% or less if acidity in the rainfall were reduced by 50%. While there may be beneficial effects of reduced S and N oxide emissions, these results suggest the resultant lower rainfall acidities are not likely to produce noticeable changes in yield of soybean.
Deposition of Air‐borne Acidifiers in the Western Environment
Authors: Young J. R. , Ellis E. C. , Hidy G. M. 
Published: July 2010

AbstractRegional deposition chemistry in the western USA is reviewed and analyzed to assess the potential for acid deposition effects in the rural West. Annual average and seasonal data from NADP/NTN sites over the period 1978 to 1984 are analyzed. These data meet specific data completeness criteria to ensure a representative wet deposition data set. Acidity levels in western precipitation are typically less than one‐fifth of their values in the East. The conventional method used to calculate annual average pH values does not account for net alkalinity present in some samples. This method overestimates acidity in the West by as much as 58% on an annual basis. Concentrations and depositions of SO2−4 and NO−3 are generally one‐tenth to one‐half of eastern values. Sulfate deposition is well below that associated with adverse effects on the environment. Sulfate concentrations are highly correlated with Ca2+ concentrations and only weakly correlated with H+ concentrations; in the East the converse is true. This result suggests the importance of suspended soil dust as a mediating factor in precipitation acidity. Dry and wet deposition in the mountainous terrain containing potentially susceptible ecosystems is estimated to be roughly equal in magnitude. Deposition from interception of cloud or fog droplets is estimated to contribute significantly to total deposition only in mountains along the Pacific Coast. Regional source‐receptor relationships in the West are poorly defined due to inadequate meteorological and deposition data. Areas in which our understanding of the acid deposition phenomenon in the West is inadequate are described. Specific objectives for acid deposition research in the West are identified and prioritized.
Bacterial Pollution in Runoff from Agricultural Lands
Authors: Baxter‐Potter Wanada R. , Gilliland Martha W. 
Published: July 2010

AbstractA review of the literature reporting the methods and results of studies concerned with the nature of nonpoint source microbial pollution leads to several conclusions: (i) Comparison of data from different studies may be complicated by variation in the choice of indicator organisms, variation in watershed size and homogeneity, and variation in media and procedures for determining fecal streptococcus densities. (ii) The ratio of fecal coliform to fecal streptococcus densities can be used to help identify particular sources of fecal pollution, but its usefulness declines with age. Its usefulness may also be affected by media and procedures used to determine fecal streptococcus densities, particularly when data derived from different media or procedures are compared. (iii) Bacterial densities in runoff from agricultural lands often exceed water quality standards. This is true of virtually all types of agricultural land. (iv) Although some connection between bacterial densities and stream discharge during storm events is apparent, the relationship is not simple. Factors such as temperature, hydrologic proximity of pollution sources, livestock management practices, wildlife activity, fecal deposit age, and channel and bank storage, all affect bacterial densities in runoff. Of these factors, only the influence of fecal deposit age on bacterial releases has been studied and quantified. (v) There is in the literature no loading function to predict bacterial densities in runoff that satisfactorily considers the factors listed above; however, typical density values may be used in a simple loading function to estimate probable density ranges.
Estimating the Availability of Nitrogen in Poultry Manure through Laboratory and Field Studies
Authors: Bitzer Carolyn C. , Sims J. Thomas 
Published: July 2010

AbstractExcessive applications of poultry (chicken, Gallus gallus domesticus) manure in some cropping systems have resulted in nitrate contamination of groundwater. To determine the application rates necessary for optimum crop growth and minimal nitrate leaching, estimates of the availability of N in poultry manure are necessary. This research investigated, under laboratory and field conditions, an approach that could be used to predict available N in poultry manure. In the laboratory study, 20 manures were incorporated with a Kalmia sandy loam (Typic Hapludults) at rates estimated to provide 100 mg predicted available N (PAN) kg−1 soil, where PAN = 80% Ni + 60% No and Ni = (NH4‐N + NO3‐N), No = (Total N − Ni). Actual available N, defined as Ni initially extractable by 2 M KCl, plus N mineralized during a 140‐d nonleached incubation study, ranged from 54 to 118 mg N kg−1 soil. A field study was also conducted at two locations comparing three poultry manures, applied at rates of 0, 90, 180, and 270 kg PAN ha−1, with ammonium nitrate (AN) applied at the same rates. Irrigated corn (Zea mays L.) was grown at both sites during 1985 and soil, plant, and yield data were obtained. Nitrogen content of ear leaf samples at mid‐silking was significantly less, at both sites, for the three manures than for AN. No significant differences in grain yields were observed between N sources at site one, but average yields (across N rate) were significantly less with two of the poultry manures (PM‐7, PM‐11), relative to AN, at site two. Postharvest soil samples (0–100 cm) were obtained from the control (0N) and 270 kg PAN ha−1 rates of all N sources. Residual Ni was less than 10 mg kg−1 for all treatments and depths; however, significantly higher (P = 0.08) NO3‐N levels were found with AN at the 60 to 80 depth cm at site two and at the 80 to 100 cm (P < 0.05) depths at sites one and two. The field study was repeated at the same sites in 1986 to assess the residual N value of manure applied in 1985. Based on ear leaf N and grain yields, residual available N from manures was determined to be less than 45 kg N ha−1. The second year decay constant for PM was estimated, by comparison with AN yields, to be 0.11 and 0.06 at sites one and two, respectively.
Effects of Acid Rain on Corn Silks and Pollen Germination
Authors: Wertheim Frank S. , Craker Lyle E. 
Published: July 2010

AbstractPollen germination was significantly reduced on corn (Zea mays L. cv. Pioneer 3747) silks exposed to an episode of simulated acid rain of pH 4.6, 3.6, or 2.6 as compared with germination on silks treated with pH 5.6 rain. Silks treated with a simulated acid rain of pH 3.6 or 2.6 developed necrotic lesions in the most distal regions. When silk tissue was immersed in a simulated acid rain of pH 3.6, the development of necrosis in the tip region was related to the duration of the exposure. Silk tissue placed in a simulated acid rain solution was able to buffer the acidity of the rain over time.
Some Observations on the Stoichiometry of Feldspar Hydrolysis in Granitic Soil
Authors: Clayton James L. 
Published: July 2010

AbstractWeathering rates of orthoclase and plagioclase were computed from mass balances of Na, K, and Ca in three forested watersheds in the Idaho batholith. On the basis of stand conditions, two watersheds were assumed to have no net gains or losses of cations in biomass, and increases in biomass were measured in the third watershed. Balanced feldspar hydrolysis reactions were established based on kaolinite as a weathering product. Free silica (SiO2) release predicted from reaction stoichiometries ranged from 94 to 99% of measured SiO2 flux from the watersheds. These results suggest that the entire flux of Na, K, and Ca can be attributed to cation release from primary mineral hydrolysis without invoking net loss of cations from exchange sites in these watersheds. The acid neutralizing capacity (ANC) arising from hydrolysis is approximately 1500 to 1700 mol(c) ha−1 yr−1. Annual H+ input from bulk precipitation currently averages 70 mol ha−1 yr−1. Attempts by other researchers to check reaction stoichiometry by SiO2 have not been particularly successful. Simple mineralogy of parent material and lack of anthropogenic sources of acid deposition may explain why predicted and actual SiO2 fluxes were similar in this study.
Boron Release and Sorption by Fly Ash as Affected by pH and Particle Size
Authors: Hollis J. F. , Keren R. , Gal M. 
Published: July 2010

AbstractThe effect of ash particle size, pH, and Ca(OH)2 presence on the dissolution and adsorption of B by fly ash in aqueous media was studied. Most of the soluble B was found in the small particles of ash. Dissolution of B was independent of the dissolution of Ca from fly ash. Decreasing the pH from 12.5 to 6 increased both the solubility and the extractability of B. A small amount of B was adsorbed by fly ash at pH 7; this was attributed to a ligand exchange mechanism. Sorption of B increased with increasing pH, up to 12, which could not be explained by ligand exchange but rather with coprecipitation with CaCO3.
Yield Responses of Field‐Grown Crops to Acidic Fog and Ambient Ozone
Authors: Takemoto B. K. , Olszyk D. M. , Johnson A. G. , Parada C. R. 
Published: July 2010

AbstractThe yield responses of five commercially important California crops (strawberry Fragaria × ananassa Duch., tomato Lycopersicon esculentum Mill., pepper Capsicum annuum L., alfalfa Medicago sativa L., celery Apium graveolens L.) to acidic fog singly, and in combination with ambient O3 were examined under field conditions, utilizing open‐top chambers and air exclusion systems. Simulated fog at pH 7.24, 2.69, or 1.68 was applied to plants twice weekly for 11 weeks. Only repeated applications of pH 1.68 fog were found to cause significant alterations in crop injury or yield responses compared to exposure to pH 7.24 fog. Necrotic lesions developed on leaves, flowers, and fruits of plants exposed to pH 1.68 fog, but not on plants exposed to pH 2.69 or 7.24 fog, or on unfogged plants. In plants grown in open‐top chambers, pH 1.68 fog significantly reduced fruit yield in strawberry, tomato, and pepper by 30 to 58%, and biomass yield in alfalfa by 11% relative to yields measured in crops exposed to pH 7.24 fog. Moreover, significant yield reductions were observed in tomato, pepper, alfalfa, and celery exposed to ambient O3 compared to crops grown in charcoal‐filtered air. The combined effects of highly acidic fog (pH 1.68) and ambient O3 were additive with respect to growth and yield responses in all five crops grown in open‐top chambers. However, since fog at current ambient levels of acidity is typically 10 to 100 times less acidic, yield losses attributable to acidic fog alone, are not likely to occur. Alternatively, yield reductions may result as a consequence exposure to ambient O3, but no interactive effect would be expected based on the results of the present study. Plant yield, growth, and injury responses to acidic fog and ambient O3 in air exclusion system plots were not similar to those exhibited by plants grown in open‐top chambers. The impacts of the applied stresses were less pronounced in plants grown in air exclusion systems, which may have been partly due to differences in environmental conditions between the exposure methodologies.
Chemical Volatilization in Nearly Dry Soils under Non‐Isothermal Conditions
Authors: Cohen Yoram , Taghavi Hutan , Ryan Patrick A. 
Published: July 2010

AbstractA theoretical investigation of the volatilization of chemical contaminants in the top layer of a nearly dry soil column under nonisothermal conditions is presented in this paper. The proposed one‐dimensional model considers the effect of natural convection, and the variations of diffusivity and vapor phase adsorption with temperature on contaminant flux across the soil‐air interface. The study has shown that natural convection effects are small. Diurnal temperature changes were found to lead to fluctuations in the concentration profiles and the volatilization flux due to alternating adsorption/desorption processes in the soil. These diurnal changes in concentration cannot be determined from isothermal calculations. Finally, it is suggested that a simple linear isothermal diffusion model may be adequate for describing the chemical concentration profiles at times that are sufficiently long past the initial soil contamination event.
Forest Harvest and Site Preparation Effects on Stormflow and Peakflow of Ephemeral Streams in the Ouachita Mountains
Authors: Miller E. L. , Beasley R.S. , Lawson E. R. 
Published: July 2010

AbstractStormflow and peakflow response to three silvicultural treatments—clearcutting, selection cutting and no disturbance (control)—were compared in a replicated small watershed study in the Ouachita Mountains of Arkansas. Watersheds were blocked according to aspect, location, soils, and geology in a randomized complete block design to test effects of treatments. Soils on the watersheds are shallow and were derived from sandstones and shale parent materials. Annual precipitation totals ranged from 72 to 142% of the long‐term average (131.7 cm) during the study and a single rainstorm exceeding the 100‐yr, 24‐h event occurred the second year following harvest treatments. Overall, stormflow water yields did not increase significantly due to forest harvest treatments apparently because permeable soils and subsurface geology allowed deep seepage at the expense of Stormflow. However, a treatment response was observed within one block and there was clearly a difference in Stormflow response between blocks of watersheds. Annual stormflow as a percentage of precipitation ranged from 2 to 59% across watersheds and years. Overall peakflows did not increase significantly due to treatment, but a treatment response was obseved within one block of watersheds and there was a significant difference in peakflows between blocks. Treatment differences in Stormflow and peakflow for the 100‐yr event were not significant. Stormflow to precipitation ratios for this event ranged from 0.63 to 0.81.
Persistence and Movement of Picloram in a Northern Saskatchewan Watershed
Authors: Smith A. E. , Waite D. , Grover R. , Kerr L. A. , Milward L. J. , Sommerstad H. 
Published: July 2010

AbstractIn the summer of 1982, 477 ha of a weapons range in northern Saskatchewan were treated with a granular formulation of picloram (4‐amino‐3,5,6‐trichloropicolinic acid) at a rate of 3.38 kg ha−1 (a.i.). For the next 2 yr, the persistence of picloram was monitored in the soil at sites within and outside the treatment area. Picloram was monitored for a 3‐yr period in the groundwater at off‐target sites and in the surface waters and sediments of a creek and two lakes adjoining the treatment area. Extensive leaching of the herbicide was noted. After 14 months residues were recovered from the 60‐ to 90‐cm soil depths, and after 22 months from the 90‐ to 120‐cm soil layer. After 26 months between 138 and 396 g ha−1 of picloram were recovered from the top 120‐cm soil depths, Picloram was detected in the top 30 cm of soils, approximately 1 km from the treatment area, when sampled 14 and 22 months following the initial application. Picloram (0.25–88.3 µg L−1) was recovered after 35 months from groundwater samples collected at 120 cm from the same off‐target sites. This transfer to nontreated sites was considered to result from a combination of blowing surface soil and groundwater movement from the treated area. Samples of surface waters taken from a lake approximately 1 km from the treatment zone indicated that picloram residues could be detected (0.1–1.15 µg L−1) in the falls of 1983 and 1984, but not in the summers of 1984 and 1985. Traces of picloram (0.14–0.39 µg L−1) were recovered in the fall of 1983 and summer of 1985 in creek waters situated approximately 300 m from the edge of the treatment area. Picloram was detected (12 µg kg−1) in only one lake sediment sample at one sampling period.
Lichens, Tree Growth, and Foliar Symptoms of Air Pollution: Are the Stories Consistent?
Authors: Muir Patricia S. , McCune Bruce 
Published: July 2010

AbstractLichen communities, tree growth, and foliar symptoms of Acer saccharum, Fraxinus spp., Liriodendron tulipifera, Quercus aiba, and the Quercus rubra group were studied in relation to air pollutants in southern Indiana and Illinois. Both study areas receive regional pollutants, but only one is close to a large coal‐fired utility, which results in a high dose of SO2 and its reaction products. Lichen communities differed significantly between the two areas; species richness and total cover were lowest in the near‐utility area, and species compositional differences suggested that air quality was responsible. Few differences were noted in foliar symptoms between areas; when symptom levels differed, they were generally highest in the remote area. Ozone‐induced stippling was found in both areas on leaves of Fraxinus spp. and Liriodendron. Although ring widths indicated depressed tree growth in the near‐utility area during years of high emissions, periodic basal area increments and tree vigor did not generally differ between areas, and were generally not related to foliar symptoms other than stippling. Ozone‐induced stippling on Liriodendron was negatively correlated with basal area increments.