bluuebunny/crossref_metadata_2025_split huggingface dataset:
USLE‐M: Empirical Modeling Rainfall Erosion through Runoff and Sediment Concentration
Authors: Kinnell P. I. A. , Risse L. M. 
Published: July 2010

AbstractRunoff is a factor in rainfall erosion, and models that include explicit consideration of runoff provide better predictions of erosion than models like the Universal Soil Loss Equation (USLE) and the revised USLE (RUSLE) that do not. The USLE‐M is a modified version of the USLE based on the rainfall erosivity factor for an event, which is the product of the 30‐min erosivity index (EI30) and the runoff ratio (QR). As a consequence, USLE‐M contains explicit consideration of the effects of soil, crop, and crop management on runoff and sediment concentration. Also, the explicit consideration of runoff means that values of many of the other factors used in the USLE have to be reevaluated because the effects of variations in factors like soil and crop management on runoff are now being treated separately from the effects on sediment concentration. We present examples of new values for the soil erodibility (K) and crop management (C) factors resulting from an analysis of data from USLE runoff and soil loss plots at a number of locations in the USA in terms of the new modified version of the USLE. The new K values varied from 1.4 to 3.9 times the USLE K values. The new C values varied from 1.1 to 32.3 times the USLE C values. Procedures are also outlined for obtaining first approximations of the new K and C values from existing USLE values. Because of the explicit consideration of runoff, USLE‐M will, as a general rule, predict event soil loss better than the USLE. The USLE and USLE‐M are equally effective in predicting erosion for impervious conditions (QR = 1) but the efficiency of the USLE decreases as the proportion of the rain infiltrating increases, while that of the USLE‐M does not.
Harvesting Effects on Long‐Term Changes in Nutrient Pools of Mixed Oak Forest
Authors: Johnson D. W. , Todd D. E. 
Published: July 2010

AbstractThe effects of sawlog harvesting (SAW) vs. whole‐tree harvesting (WTH) on C and nutrient budgets of a mixed oak forest near Oak Ridge, TN, were assessed by sampling soils and vegetation just prior to and 15 yr after harvesting. Fifteen years after harvest, large woody residues in the SAW treatment lost >80% of their mass and nutrient content. Greater concentrations of Ca, K, and Mg were found in both foliage and soils in the SAW treatment than in the WTH treatment, but there were no signs of deficiency in these nutrients and no differences in growth due to treatment. There were nod eclines in exchangeable Ca2+ in the WTH treatment, and the increases in soil exchangeable Ca2+ pools in the SAW watersheds were approximately equal to the amount of Ca2+ released by decomposing residues. On the other hand, no treatment effects on soil C, vegetation biomass, species composition, vegetation N or P concentration, soil bulk density, or soil N were found 15 yr after treatment. Contrary to what has been speculated on regarding the basis of nutrient budgets, this study showed no detrimental effects of WTH on productivity or soil nutrient status (i.e., reductions from preharvest conditions). The results did show, however, that nutrients (especially Ca) from logging residues are largely retained in soils and reflected in elevated foliar nutrient concentrations.
Wheat Root Growth Responses to Enhanced Ammonium Supply
Authors: Gao S. , Pan W. L. , Koenig R. T. 
Published: July 2010

AbstractSlowing nitrification with a nitrification inhibitor (NI) provides an enhanced NH4 supply (EAS), which has improved N uptake efficiency and crop yield. A physiological response to EAS has been demonstrated in container experiments with restricted rooting volumes and uniform N distribution, but less is known about root responses to EAS when distributions of N forms are not uniform. Greenhouse and 2‐yr field experiments were conducted to determine how the root system of wheat (Triticum aestivum L.) responds to EAS. Three N sources: (i) calcium nitrate (NO3); (ii) urea with a nitrification inhibitor, nitrapyrin (NH4 + NI); and (iii) 50% NO3 + 50% NH4 + NI were uniformly incorporated in the field into the top 20 cm of a Shano silt loam soil (Coarse‐silty, mixed, superactive, mesic Xeric Haplocambid). Urea with a NI increased NH4 in the top 30 cm of soil and increased root surface area densities in this soil layer at the boot stage in both years. Rooting was either decreased or not affected by NH4 + NI relative to NO3 in the 30‐ to 90‐cm subsoil. In a greenhouse experiment, NO3, NH4 + NI, or NH4 + NI + CaCl2 were uniformly mixed into the top 20 cm of soil (diffused) or banded at the 20‐cm depth in rooting‐boxes (5 by 17 by 70 cm). Nodal root density at boot stage increased in the fertilized zones with NH4 + NI, mostly in the presence of CaCl2, compared with NO3, while seminal roots in the fertilized zones were only enhanced by banded NO3. Wheat root types responded differentially to N forms and the associated differences in vertical distribution.
Nitrogen Mineralization from Soil Organic Matter and Crop Residues: Field Validation of Laboratory Predictions
Authors: Honeycutt C. Wayne 
Published: July 2010

AbstractAccurate prediction of N mineralization under field conditions would promote optimal N‐use efficiency from both organic and inorganic sources. This study was conducted to assess the utility of microplot cylinders with mixed‐bed exchange resins for monitoring field N mineralization, to compare laboratory predictions with field measurements of N mineralization, and to determine the impact of using ground (≤1 mm) crop residues in the laboratory to predict N mineralization of unground (≤25 mm) residues in the field. Nitrogen mineralization from soil organic matter and hairy vetch (Vicia villosa Roth) residues was followed in the laboratory at 15, 20, and 25 °C with 0, 2150, 4300, and 6450 kg vetch ha‐1 equivalent loading rates of ≤1 mm particle‐size residue. Ground and unground residues were added to microplot cylinders at loading rates equivalent to 0, 4028, and 5010 kg vetch ha‐1 and installed in potato (Solanum tuberosum L. Norwis) crop rows in two growing seasons. Nitrogen mineralization from soil organic matter under field conditions was overestimated by laboratory predictions; however, field measurements of N mineralization from both ground and unground vetch residues were closely predicted by a complementary laboratory study. These data indicate vetch residue N mineralization under these modified field conditions (i.e., microplot cylinders) can be predicted from laboratory studies that use ground residues, constant temperatures, and variable residue quantities. This finding may advance our ability to model and account for residue N mineralization when developing N management recommendations.
Disturbances During Minirhizotron Installation Can Affect Root Observation Data
Authors: Joslin J. Devereux , Wolfe Mark H. 
Published: July 2010

AbstractUse of minirhizotrons in forested ecosystems has produced considerable information on production, mortality, distribution, and the phenology of root growth. But installation of minirhizotrons severs roots and disturbs soil, which can cause root proliferation in perennial plants. We compared the magnitude and vertical distribution of root growth observations in a mature hardwood forest during the growing season immediately after minirhizotron installation with observations more than two years later. We also compared the vertical root growth distribution during these two different years with the preinstallation distribution of fine root biomass. Before minirhizotron installation and again two years later, about 74% of fine root biomass was in the upper 30 cm of soil, but immediately after installation, 98% of the root elongation was in the upper 30 cm. Large differences in the quantity of root elongation were observed across different slope positions in the minirhizotron data from the first growing season (approximately four times greater on the upper slope as the lower slope). Such differences with slope position were not seen in the later minirhizotron data, nor in the preinstallation fine root biomass data. The evidence suggests that the minirhizotron data collected immediately after installation can be biased by disturbance of roots and soil during installation, which result in excessive root proliferation, particularly near the soil surface. Root proliferation appears to be the result of a response to both root pruning and to nutrient release in microsites near the newly installed minirhizotron.
General Model for Unsaturated Hydraulic Conductivity for Soils with Lognormal Pore‐Size Distribution
Authors: Kosugi K. 
Published: July 2010

AbstractDescribing water flow in unsaturated soils requires knowledge of the unsaturated hydraulic conductivity. This study was conducted to develop a general conductivity model for soils with lognormal pore‐size distribution based on the Mualem‐Dagan pore‐scale model. The derived model has three parameters other than parameters for a retention model: the parameters α and β, both of which are related to the soil pore tortuosity, and the parameter γ to describe how to evaluate the effective pore radius. The proposed model was applied to observed retention and conductivity data sets for 200 soils. Results showed that both α and β should be treated as fitted parameters for accurate descriptions of conductivity, whereas estimation results were insensitive to γ as long as α and β were optimized. Consequently, a simplified form of the general conductivity model was suggested which uses the constant γ value of unity. Based on the simplified general conductivity model, two predictive methods (AB and FN) were developed. The method AB uses the constant α and β values to minimize the average prediction error. The method FN uses an empirically derived relationship between β and the dimensionless parameter of the retention model, and the constant α value to minimize the average prediction error. Both methods reduced the average prediction error more than 77% compared with the Burdine and Mualem predictive models. The method FN provided slightly better predictions than the method AB, reducing the average prediction error by 28%.
Defining the “Ideal” Soil Structure in Surface Soil of a Typic Fluvaquent in the Netherlands
Authors: Bouma J. , Droogers P. , Peters P. 
Published: July 2010

AbstractTraditional soil structure descriptions are static and qualitative. However, measurement of basic physical and chemical characteristics of a given soil structure followed by simulation modeling of crop yields and water and nutrient regimes results in a dynamic and quantitative soil structure characterization. Within any given soil series, different types of structure may occur as a result of different management practices, and each structure type can thus be characterized. This, however, is a reactive approach in which soil structures are presented as given fact. This paper explores a proactive approach in which measurement of basic soil characteristics on a series of standardized structure samples and exploratory simulation modeling are used to define an “ideal” structure, using plant growth and nutrient‐use efficiency as indicators. Management practices to realize such an “ideal” structure remain to be designed by others. Quantitative indicators for the “ideal” structure in the 0‐ to 30‐cm surface soil of a loamy, mixed, mesic Typic Fluvaquent (a prime agricultural soil in the Netherlands) were based on simulated yields and associated nitrate leaching. Simulations considered water supply capacity, occurrence of by pass flow and internal catchment, leaching of nitrates as a function of fertilization scenarios, accessibility of water to roots, and trafficability in spring. Exploratory simulations, using a validated model for a period of 30 yr to express temporal variability for a complete soil profile with varying topsoil structures, showed a structure consisting of 0.5‐cm aggregates and a bulk density of 1.6 g cm‐3 to be “ideal” for the agricultural land use being considered.
Water‐Use Efficiency and Carbon Isotopic Composition in Reduced Tillage Systems
Authors: Walley F. L. , Matus A. , Lafond G. P. , van Kessel C. 
Published: July 2010

AbstractCropping systems that influence soil water availability are expected to influence the C isotopic composition (δ13C) of crop residues and consequently, the δ13C of soil organic matter. We hypothesized that the δ13C of plant residues and soil organic matter in three tillage systems (zero [ZT], minimum [MT], and conventional tillage [CT]) and three, 4‐yr crop rotations would vary and would relate to water‐use efficiency (WUE). The study was conducted on an Indian Head heavy clay (Udic Haploboroll) in Saskatchewan, Canada. The three crop rotations were fallow‐spring wheat (Triticum aestivum L.)‐spring wheat‐winter wheat, spring wheat‐spring wheat‐flax (Linum usitatissimum L.)‐winter wheat, and spring wheat‐flax‐winter wheat‐field pea (Pisum sativum L.). Water use was estimated yearly using mass balance. The δ13C of the standing crop residue, roots, and soil organic matter was determined 9 yr after the study was initiated. Although crop water use was higher in ZT (31.2 cm yr‐1) and MT (30.9 cm yr‐1) than in CT (28.8 cm yr‐1), corresponding differences in WUE and δ13C of plant tissue and soil organic matter were not detected. In one instance, within the most diversified rotation, WUE was reduced in ZT compared with CT; however, observed variations in WUE did not conform to theoretical expectations of the δ13C of plant residues and soil organic matter. Factors other than WUE, including soil fertility and timing of moisture deficits, may have influenced the degree to which C isotope discrimination was expressed in the plant residues and soil organic matter.
Availability of Nitrogen in 15N‐Labeled Ruminant Manure Components to Successively Grown Crops
Authors: Jensen B. , Sørensen P. , Thomsen I. K. , Christensen B. T. , Jensen E. S. 
Published: July 2010

AbstractTo improve crop N use efficiency of animal manures, the availability of N in individual manure components must be better understood. This microplot field study quantifies crop offtakes of N in four similar batches of ruminant manure containing 15N‐labeled urine, feces, or straw, or unlabeled components only. The urine and feces were from a sheep first fed unlabeled hay and then 15N‐labeled hay. Manures (≈ 19 g total N m‐2) were incorporated into two coarse‐textured soils before planting to spring barley (Hordeum vulgare L.) undersown with perennial ryegrass (Lolium perenne L.). Manures with one 15N‐labeled component were supplemented with unlabeled NH4NO3 (7.3 g N m‐2), while unlabeled manure was given 15NH415NO3. Labeled and unlabeled N were determined in the spring barley at maturity and in six cuts of ryegrass taken during the succeeding 2.5 yr. The homogeneity of feces and urine 15N‐labeling was high. Dry matter yields and crop N offtakes were similar in all treatments. Barley (grain and straw) recovered 40, 26, 10, and 6%, respectively of 15N added with mineral fertilizer, urine, straw, and feces. Weighted mean recovery of the combined manure and fertilizer dressing was 22% of the added 15N. Crop recovery of urine and feces 15N was smaller and that of straw 15N higher than reported in previous studies on individual components, indicating that the N mineralization‐immobilization turnover (MIT) of the manure components interacted. In the second and third growth seasons, 2.7 to 4.4% and 1.1 to 2.0% of the 15N was recovered in grass cuts, respectively. Total recovery ranged from 84 to 95% of the added 15N, suggesting small N losses from this cropping system.
Revisiting the Simplified Bernoulli Equation
Authors: Heys Jeffrey J , Holyoak Nicole , Calleja Anna M , Belohlavek Marek , Chaliki Hari P 
Published: July 2010

Background:
The assessment of the severity of aortic valve stenosis is done by either invasive catheterization or non-invasive Doppler Echocardiography in conjunction with the simplified Bernoulli equation. The catheter measurement is generally considered more accurate, but the procedure is also more likely to have dangerous complications.

Objective:
The focus here is on examining computational fluid dynamics as an alternative method for analyzing the echo data and determining whether it can provide results similar to the catheter measurement.

Methods:
An in vitro heart model with a rigid orifice is used as a first step in comparing echocardiographic data, which uses the simplified Bernoulli equation, catheterization, and echocardiographic data, which uses computational fluid dynamics (i.e., the Navier-Stokes equations).

Results:
For a 0.93cm2 orifice, the maximum pressure gradient predicted by either the simplified Bernoulli equation or computational fluid dynamics was not significantly different from the experimental catheter measurement (p > 0.01). For a smaller 0.52cm2 orifice, there was a small but significant difference (p < 0.01) between the simplified Bernoulli equation and the computational fluid dynamics simulation, with the computational fluid dynamics simulation giving better agreement with experimental data for some turbulence models.

Conclusion:
For this simplified, in vitro system, the use of computational fluid dynamics provides an improvement over the simplified Bernoulli equation with the biggest improvement being seen at higher valvular stenosis levels.
“We All Go a Little Mad Sometimes”: Alfred Hitchcock, American Psychoanalysis, and the Construction of the Cold War Psychopath
Authors: Genter Robert 
Published: July 2010

Abstract:This article explores the image of the psychopath in Alfred Hitchcock's 1960 film Psycho. The famed director's portrayal of a psychologically damaged young man connected with a much larger discussion over political and sexual deviance in the early Cold War, a discussion that cantered on the image of the psychopath as the dominant threat to national security and that played upon normative assumptions about adolescent development and mother-son relations.
Distribution of air bubbles in the EDML and EDC (Antarctica) ice cores, using a new method of automatic image analysis
Authors: Ueltzhöffer Kai J. , Bendel Verena , Freitag Johannes , Kipfstuhl Sepp , Wagenbach Dietmar , Faria Sérgio H. , Garbe Christoph S. 
Published: July 2010

AbstractAir bubbles in ice cores play an essential role in climate research, not only because they contain samples of the palaeoatmosphere, but also because their shape, size and distribution provide information about the past firn structure and the embedding of climate records into deep ice cores. In this context, we present profiles of average bubble size and bubble number for the entire EDML (Antarctica) core and the top 600 m of the EDC (Antarctica) core, and distributions of bubble sizes from selected depths. The data are generated with an image-processing framework which automatically extracts position, orientation, size and shape of an elliptical approximation of each bubble from thick-section micrographs, without user interaction. The presented software framework allows for registration of overlapping photomicrographs to yield accurate locations of bubble-like features. A comparison is made between the bubble parameterizations in the EDML and EDC cores and data published on the Vostok (Antarctica) ice core. The porosity at the firn/ice transition is inferred to lie between 8.62% and 10.48% for the EDC core and between 10.56% and 12.61 % for the EDML core.
Changes in the elevation and extent of two glaciers along the Yanglonghe river, Qilian Shan, China
Authors: Shangguan Donghui , Liu Shiyin , Ding Yongjian , Zhang Yingsong , Li Jing , Li Xiangying , Wu Zhen 
Published: July 2010

AbstractWe use topographic maps, historical data, multispectral satellite data and real-time kinematic GPS data to analyze glacier area, length and ice-elevation changes of two glaciers in the central Qilian Shan, China, between 1956 and 2007. We find that the fronts of Yanglonghe glacier No. 1 (5Y432A1) and Yanglonghe glacier No. 5 (5Y432A5) have retreated by 266.5 ± 37.1 m (5.2 ± 0.73 m a−1) and 181.4 ± 37.1 m (3.6 ± 0.73 m a−1) respectively, and that this retreat accelerated after 1999. During the study period, the glacier areas decreased by ∼4.1% and 15.9% respectively. In addition, spatially non-uniform thinning, which averaged 20.2 ± 11 m (0.4 ± 0.22 m a−1) and 16.9 ± 11 m (0.33 ± 0.22 m a−1) in the ablation areas of 5Y432A1 and 5Y432A5 respectively, is observed using digital elevation models constructed using data from 1956, 1977 and 2007. The ice-volume depletion from 5Y432A1 (2.91 × 107 m3) was 2.7 times greater than from the smaller 5Y432A5 (1.08 × 107 m3). Based on records from nearby Tuole weather station, increasing annual temperatures are principally responsible for the observed glacier thinning and retreat.
Hulls of Ring Extensions
Authors: Birkenmeier Gary F. , Park Jae Keol , Rizvi S. Tariq 
Published: July 2010

AbstractWe investigate the behavior of the quasi-Baer and the right FI-extending right ring hulls under various ring extensions including group ring extensions, full and triangular matrix ring extensions, and infinite matrix ring extensions. As a consequence, we show that for semiprime rings R and S, if R and S are Morita equivalent, then so are the quasi-Baer right ring hulls of R and S, respectively. As an application, we prove that if unital C*-algebras A and B are Morita equivalent as rings, then the bounded central closure of A and that of B are strongly Morita equivalent as C*-algebras. Our results show that the quasi-Baer property is always preserved by infinite matrix rings, unlike the Baer property. Moreover, we give an affirmative answer to an open question of Goel and Jain for the commutative group ring A[G] of a torsion-free Abelian group G over a commutative semiprime quasi-continuous ring A. Examples that illustrate and delimit the results of this paper are provided.
On the Maximal Operator Ideal Associated with a Tensor Norm Defined by Interpolation Spaces
Authors: Puerta M. E. , Loaiza G. 
Published: July 2010

AbstractThe classical approach to studying operator ideals using tensor norms mainly focuses on those tensor norms and operator ideals defined by means of ℓp spaces. In a previous paper, an interpolation space, defined via the real method and using ℓp spaces, was used to define a tensor norm, and the associated minimal operator ideals were characterized. In this paper, the next natural step is taken, that is, the corresponding maximal operator ideals are characterized. As an application, necessary and sufficient conditions for the coincidence of the maximal and minimal ideals are given. Finally, the previous results are used in order to find some new metric properties of the mentioned tensor norm.
Work flexibility as a mediator of the relationship between work–family conflict and intention to quit
Authors: Porter Stacey , Ayman Roya 
Published: July 2010

AbstractIn a sample of 243 women from a Midwestern healthcare organization, we found that the work-to-family interference (WIF) was positively related to intentions to quit. Significant relationships were found among work flexibility, WIF, and intention to quit. This relationship was supported, allowing us to conclude that employees who perceive personal control and autonomy in their work environment (as defined by how, when and where they work) will report lower levels of WIF and intentions to quit. The implications of these findings on future research and organizational practice are discussed.