bluuebunny/crossref_metadata_2025 huggingface dataset:
Some Factors Affecting Soil Sampling
Authors: Welch C. D. , Fitts J. W.
Published: July 2010

A study was conducted to obtain information as to the effects of tools used and depth of sampling on results of soil analysis. All samples were analyzed for pH, phosphorus, potassium, and organic. matter. Some of the principle findings were as follows:

There was no significant difference between results of analysis for samples collected with a tube, spade, or trowel. The pH and organic matter values were significantly lower for samples collected with the auger as compared to the other tools. There was no significant difference between analyses for duplicate samples collected in a bucket.

There was a significant decrease in the pH of soil with depth from the 0 to 3 to the 3 to 6 to the 6 to 9 inch layers of soil in fields seeded to sod crops. The difference was not significant for comparable fields used for row crops. The amount of phosphorus, potassium and organic matter decreased with depth in fields used for sod crops as well as those in row crops.

The soil analyses results for pH, phosphorus, and potassium and organic matter were significantly lower for samples composited from 0 to 6‐inch cores as compared to 0 to 3‐inch cores for fields in sod crops in the Coastal Plains as well as the Piedmont and Mountains. Samples from 0 to 6‐inch cores in fields used for row crops showed significantly lower results than those from 0 to 3‐inches for pH, potassium, and organic matter in the Piedmont and Mountains but only for organic matter in the Coastal Plains.
Factors Affecting Mass Movement of Four Soils in the Western Cascades of Oregon
Authors: Paeth R. C. , Harward M. E. , Knox E. G. , Dyrness C. T.
Published: July 2010

Four soils derived from tuffaceous rock in the Western Cascades were studied to determine relationships to slope stability. Two of the soils derived from greenish tuff and breccia were prone to slope failure. The other two soils were derived from yellowish and reddish tuff and breccia and were more stable.

Soils prone to slope failure were characterized by high amounts of smectite clay, absence of kaolin, and moderate amounts of free iron oxide. The more stable soils contained kaolin, more chlorite and chloritic intergrades, less smectite, and higher amounts of free iron oxide.

Pseudomorphs of clay were the major component of silt and sand fractions. The pseudomorphs seem to function mechanically as primary soil particles but the clay contributes to cation exchange and moisture retention. The ratio of clay calculated from 15‐bar moisture retention to measured clay was highest for the most stable soils.

Stability of these soils did not appear to correlate with clay content, content of amorphous clay, or proportions of exchangeable cations. Color of the soils and of their source rocks was correlated with clay mineralogy, content of iron oxides, and landscape stability.
Artificial Weathering of Oxidized Biotite: I. Potassium Removal by Sodium Chloride and Sodium Tetraphenylboron Solutions
Authors: Gilkes R. J. , Young R. C. , Quirk J. P.
Published: July 2010

The rate of release of interlayer potassium from biotite to NaCl and NaCl/sodium tetraphenylboron solutions is determined by the oxidation state of octahedral iron. Octahedral cation vacancies are generated when octahedral iron is oxidized resulting in a change of orientation of hydroxyl from perpendicular to the mica layer to parallel. This in turn produces a more stable environment for interlayer potassium. Infrared absorption measurements show that the abundance of inclined hydroxyl bears a negative linear relation with the amount of potassium removed by leaching.
Layer Charge Decrease by Tetrahedral Cation Removal and Silicon Incorporation during Natural Weathering of Phlogopite to Saponite
Authors: Sridhar K. , Jackson M. L.
Published: July 2010

A substantial layer charge decrease, from 210 to 140 meq/100 g, occurred during the natural weathering of phlogopite through vermiculite to saponite in Kansas. A comparison of the Fe2+ content and layer charge of the coarse fraction (72% phlogopite) and the fine fraction (71% saponite) indicated that iron oxidation cannot account for the layer charge decrease during the transformation. Control studies on iron oxidation during vermiculitization of biotites and lepidomelane did not correlate with layer charge decrease.

Elemental analysis of the coarse and fine fractions revealed gains and losses of cations during the weathering of the mica flakes to fine particles. The Si4+ and Mg2+ increased by 2.66 and 0.84%, respectively, while Al3+ and total Fe3+ plus Fe2+ decreased by 0.34 and 1.21%, respectively, in the two fine fractions compared to the macroflakes. The elemental analyses also revealed the unique nature of this phlogopite which contained fewer moles of Al3+ than K+; the presence of some isomorphously substituted tetrahedral Fe3+ contributed 17% of the total negative layer charge. Loss of layer charge was found to be a result of the loss of isomorphically substituted tetrahedral Al3+ and Fe3+ by authigenic recrystallization with an increase in tetrahedral Si4+. In control studies, removal of isomorphously substituted tetrahedral Al3+ from Ontario phlogopitic vermiculite and Transvaal micaceous vermiculite by citrate chelation also resulted in an equivalent layer charge decrease.
Surface Properties and Forces Holding Water in Allophane Soils
Authors: Rousseaux J. M. , Warkentin B. P.
Published: July 2010

Surface area and micropore size distribution were calculated from measurements of adsorption of water vapor at 25°C on a group of allophane soils from the West Indies and from Japan. The changes in pore‐size distribution on drying were measured. Specific surface area varied between 100 and 400 m2/g, and the dominant pore radius was about 7Å. Cation‐exchange capacity measured with different cations also varied with pore‐size distribution.

Water retention properties were interpreted in relation to the proportion of micropores, and the chemical composition of allophane component of the soils. Pore geometry and the chemical nature of surfaces determined water retention of these allophane soils. This is in contrast to soils containing crystalline clays where the magnitude of the surface area primarily determines water retention.
Decomposition of Fungal Mycelia and Humic‐type Polymers Containing Carbon‐14 from Ring and Side‐chain Labeled 2,4‐D and Chlorpropham
Authors: Wolf D. C. , Martin J. P.
Published: July 2010

Hendersonula toruloidea and Stachybotrys atra were grown on a liquid peptone‐dextrose medium containing 10 ppm ring‐ or side‐chain 2‐14C labeled 2,4‐D (2,4‐dichlorophenoxyacetic acid), or chlorpropham (isopropyl m‐chlorocarbanilate). Approximately 12% of the activity from ring‐14C 2,4‐D was present in the humic polymers produced by the fungi, and 4 to 16% was recovered in the mycelia. The mycelia of both fungi contained approximately 35% of the activity from either ring‐ or 2‐14C chlorpropham and the humic polymers from 3 to 24% of the added activity. The decomposition percentages of the 14C portions of H. toruloidea and S. atra from ring‐14C 2,4‐D were 15 and 35% and 13 and 35%, respectively, for the mycelia and humic polymers. The label from 2‐14C 2,4‐D was released as 14CO2 at rates greater than twice that for the ring‐14C 2,4‐D. Similarly, the carbon from ring‐14C chlorpropham associated with H. toruloidea and S. atra mycelia and humic polymers was more resistant to decomposition than that from 2‐14C chlorpropham. The results indicate that 2,4‐D and chlorpropham or more probably their partial degradation products may be incorporated into microbial cells or products, some of which are relatively resistant to microbial degradation.
Increased Selectivity of Naturally Weathered Biotites for Potassium
Authors: Tarzi J. G. , Protz R.
Published: July 2010

Mica particles from six residual soils were separated from different horizons and separated into three weathering classes. Potassium contents in the centers and in the edges of mica particles were determined by using electron probe microanalysis techniques. The results showed that biotites tended to regain K after an initial loss becoming more resistant to weathering. The regained K concentrated at the edges of weathered biotite particles.
Predicting Hysteretic Effects in Evaporation from Bare Soil
Authors: Staple W. J.
Published: July 2010

Evaporation losses from initially dry soil moistened by simulated rainfall were computed on the assumption that the soil water pressure on drying was uniquely predicted by either the wetting or drying boundary curve of the hysteresis function. In other words, hysteretic effects involving detailed drying scanning curves were neglected. The results showed that computed evaporation losses based on the two unique curves were nearly equal, and that these losses were only about one‐half of those established previously both by evaporation measurement and by computations based on the appropriate scanning curves. It is concluded that hysteretic effects cannot be neglected or estimated by a simple averaging procedure in predicting water conservation in summerfallow under semiarid conditions.
Manganese Adsorption and Desorption in Calcareous Lebanese Soils
Authors: Curtin D. , Ryan J. , Chaudhary R. A.
Published: July 2010

Adsorption data for 20 calcareous soils, obtained by equilibrating soil samples with 9 different concentrations of Manganese, were evaluated using Langmuir adsorption equations. When the data were plotted according to the conventional Langmuir equation, the isotherms were curvilinear at low Mn concentrations and linear at higher concentrations. Where the data were fitted to a “competitive” Langmuir equation, the isotherms were again found to be nonlinear, indicating that more than one population of adsorption sites existed in these soils. Manganese adsorption maxima, estimated from the linear parts of the conventional Langmuir isotherms, were highly correlated with the cation exchange capacity (CEC) of the soils but not with values of organic matter content, calcium carbonate equivalent or free iron. A desorption study confirmed that part of the adsorbed Mn was held quite tightly.
Effect of Exchangeable Sodium on Soil Electrical Conductivity‐Salinity Calibrations
Authors: Bottraud Jean‐Christophe , Rhoades J. D.
Published: July 2010

This study was undertaken to ascertain if soil sodicity significantly influences soil electrical conductivity (σa) — salinity calibrations. Laboratory columns of Fallbrook (Typic Haploxeralfs) and Yolo (Typic Xerorthents) soils were adjusted to various levels of salinity and sodicity by leaching them with solutions varying in electrical conductivity (σw) and sodium adsorption ratio (SAR); then σa was measured using four‐electrode techniques. Calibrations obtained between σw and σa over the σw range 2 to 20 were compared at different levels of SAR ranging between 0 to 80 or 400. The calibrations between σw and σa were found to be insignificantly influenced by variations in SAR over the range studied. Normal variations in the exchangeable Na contents of typical saline, arid‐land soils should not cause any serious misdiagnosis of soil salinity based on measurements of bulk σa and use of σw‐σa calibrations.
Erosion‐sedimentation in a Closed Drainage Basin in Northwest Indiana
Authors: Norton L. Darrell
Published: July 2010

A closed drainage basin representing a catchment for eroded sediment was studied to determine the amount of erosion since cultivation began, and to determine the spatial relationships of the erosion‐sedimentation process that had occurred during 145 yr of agriculture. Post‐settlement alluvium (PSA) thickness was easily determined in the field as light‐colored mineral soil overlying highly decomposed (sapric) organics in the depression. A detailed field study of the PSA, other geologic sediments, loess, and the original till surface in the watershed demonstrated a reduction in the original relief. The mass of PSA served as a measure of the amount of soil eroded from peripheral slopes. The long term average soil loss was > 26 Mg ha−1 yr−1, which represented an average removal of over 24 cm of soil from the entire watershed in 145 yr. The maximum slope in the watershed was 5%. The loess thickness on the surrounding slopes was used as an indication of the spatial variation of erosion processes. Summit positions and convex slope shapes having divergent runoff had the most erosion while concave shapes with convergent runoff exhibited more sedimentation. These results are essentially opposite to those predicted by the Universal Soil Loss Equation (USLE). Accurate prediction models in the future should consider the dynamic aspects of erosion‐sedimentation on landscapes.
Estimating the Variability of Unsaturated Soil Hydraulic Conductivity Using Simple Equations
Authors: Wagenet R. J. , Addiscott T. M.
Published: July 2010

Description of transient water flow requires knowledge, or estimation, of the relationship between the unsaturated soil hydraulic conductivity, K, and volumetric water content. A variety of studies have related K(θ) to the saturated conductivity Ko by equations involving the volumetric water content, θ, and its value at saturation, θo. The relationship is expressed here in terms of either the difference between θ and θo or the ratio of θ to θo, so that K(θ) is obtained by multiplying Ko by exp[β(θ − θo)] or by [θ/θo]2b + 3 respectively, with β and b being constants for any one sampling point. The quantity β in the equation involving (θ − θo) can be obtained from field data by four different mathematical methods. When this equation was used to compute distributions of lnK(θ) from measured distributions of lnKo and lnβ, the first four moments of the resulting distributions of lnK(θ) all differed considerably according to the mathematical method used, although Ko and β were derived in each case from the same set of field data. When both equations were used to estimate lnK(θ), using the same distributions of lnKo and appropriate distributions of lnβ or lnb, there were large differences between them in the moments of the resulting distributions. The estimate of lnK(θ) from the equation using θ/θo had much the larger variance, mainly because the variance of lnb was about three times that of lnβ.
Design for an Automated Tension Infiltrometer
Authors: Ankeny M. D. , Kaspar T. C. , Horton R.
Published: July 2010

An automated tension infiltrometer useful for a range of water tensions from 0.02 to 0.50 m and for infiltration rates of 1 × 10−8 to 5 × 10−4 m s 1 is described. Infiltration rates are calculated from the change in water height in a Mariotte column. Water height is automatically measured by using the difference in tension between two pressure transducers, one installed at the top, and the other at the bottom, of the Mariotte column. Precision of water height measurement using two transducers (SD = 2.2 mm) is increased as compared with height measurements made with only one transducer (SD = 6.2 mm). With only one transducer, much of the measurement error is due to tension fluctuations or “noise” caused by bubbling in the Mariotte column. The new design also incorporates several features used or suggested by other workers. A bubble tower is used for tension regulation, and interchangeable Mariotte columns of different diameters are used to match column volume with expected cumulative infiltration. Advantages of the new device include (i) quick and accurate tension control at low tensions, (ii) improved measurement precision at low flow rates, and (iii) automatic measurement and data collection, which increases measurement speed and eliminates bubbling‐induced variability.
A Sequential Extraction Procedure with Concentrated Sulfuric Acid and Dilute Base for Soil Organic Phosphorus
Authors: Bowman R. A.
Published: July 2010

A total soil organic P (TPo) method that retains the relative ease of the dry combustion method and still preserves essentially all organic P in the extract would be desirable. A sequential extraction procedure for TPo with concentrated sulfuric acid and dilute base was therefore developed to meet these objectives. The method was based on the high efficiency of Po extracted from soils by the heat of solution created by addition of water to concentrated H2SO4. In this step of the procedure, 79% of the total Po was extracted. The acidic soil residue was next treated with NaOH to complete the extraction of Po. The sum of the acid‐ and base‐extractable Po gave a measure of the total soil Po. The method did not hydrolyze or only minimally hydrolyzed Po substrates added to test soils. The proposed procedure was compared with the Mehta extraction method, and with an ignition method developed by Saunders and Williams. In a test of 12 different soils (prairie to highly weathered) the proposed procedure extracted an average of 4% more Po than did the Mehta, and 17% less Po than the Saunders and Williams procedures. The proposed procedure is more rapid than either of the other procedures, and is equally precise. The ease with which the proposed method can be performed as stated, or performed in combination with the high temperature base extraction of the Mehta procedure, makes it ideal for routine laboratory use, especially when the nature of the Po compounds also is being investigated.
Phosphate Sorption by Calcareous Vertisols and Inceptisols of Spain
Authors: Solis P. , Torrent J.
Published: July 2010

The study of phosphate sorption by soils has practical interest but little is known on the quantitative importance of phosphate sorption by Vertisols and the soil properties affecting it. In this study we examined phosphate sorption by 24 samples of calcareous Vertisols and associated Inceptisols of southern Spain. Sorption isotherms were described by the Freundlich equation. The amount of phosphate sorbed at 6 d at 1 mg P L−1 equilibrium concentration was highly correlated with the percentages of citrate‐dithionite‐bicarbonate extractable Fe (Fe4) and clay; regression analysis suggested that the Fe oxides, as estimated by Fed, were the most active sorbents. In contrast calcium carbonate seemed to play a secondary role in sorption. Phosphorus buffer capacity was also highly correlated with the content in Fe oxides (r = 0.79) but less with clay content. Little sorption took place after 6 d for equilibrium concentrations of about 1 mg P L−1. Long‐term sorption was affected by calcium carbonate content; Fe oxides seemed to contribute little to that process. Buffer capacity measured from P quantity and intensity changes produced by cropping was similar in magnitude and weakly correlated with the buffer capacity calculated from sorption isotherms in the laboratory. Thus, sorption curves can provide an estimate of the buffer capacity in desorption by plants for the soils studied.
Copper and Cadmium Effects on Potassium Adsorption and Buffering Capacity
Authors: Yang Jae E. , Skogley Earl O.
Published: July 2010

Trace metals have accumulated in many soils from application of mine wastes, sewage sludges, and other residues. Toxic effects of heavy metals on plants growing in contaminated soil have been well documented, but related effects of heavy metals on nutrient availability, e.g., K, are limited. This research was conducted to investigate influences of Cu or Cd added as Cl salts on K adsorption kinetics, K buffering capacity, and relative distribution of K between solution and solid phase. Amsterdam silty clay loam (Typic Haploboroll) was equilibrated with H2O (Soil/H2O = 1:10) containing seven levels of K and three levels of Cu or Cd at 5 and 20 °C for 0.25 to 336 h. The major species of K, Cu, and Cd were K and Cu in the K‐Cu system, and K, Cd, and CdCl in the K‐Cd system as calculated by GEOCHEM. The kinetics of K adsorption was best described by the Elovich equation. Potassium adsorption was rapid, occurring in less than 15 min, followed by a gradual continuous adsorption. The amount of K adsorbed decreased more from Cu than from Cd additions. Reaction rate constants decreased with increasing Cu and Cd. Potassium buffering capacity decreased 20 to 32% and 7 to 20%, respectively, from addition of 400 mg Cu or Cd kg−1 soil. Copper and Cd changed the distribution of K, Ca, and Mg between soil and solution. Soil‐selectivity order for these cations was Ca > Mg > K. Additions of Cu and Cd increased exchange‐site selectivity for K more than that of Mg or Ca, in that order. Potassium‐Ca distribution was influenced more by Cu and Cd than was K‐Mg distribution. Results suggest that trace‐metal contamination of the soil might influence soil K availability by changing K adsorption kinetics, buffering capacity, and distribution.
Mapping Ordinal Data in Soil Survey: A Costa Rican Example
Authors: Bregt A. K. , Stoorvogel J. J. , Bouma J. , Stein A.
Published: July 2010

In most soil surveys, and particularly those carried out in developing countries, the bulk of recorded soil data is on an ordinal measurement scale. This determines the type of statistics and techniques that can be used for data processing. For example, with ordinal data the mode, median, and range can be used as summary statistics. For describing the spatial structure of ordinal data we propose the spatial‐difference‐probability function, which is comparable with the semivariogram. From a soil survey in Costa Rica, three different suitability maps for banana (Musa x paradisiaca L.) were produced according to a qualitative land‐evaluation procedure by interpreting: (i) the 1:200 000 soil map, (ii) the 1:50 000 soil map, and (iii) point data. The quality of these three maps was tested by looking at the reliability, relevance, and presentation of information, using 98 test borings. Reliability was characterized in terms of purity and range. The suitability map based on the 1:200 000 soil map was the most reliable one, with an overall purity of 49%. The suitability map produced by interpolating point data was the most relevant one, as defined in terms of the possibility to correctly identify potential locations for banana plantations from the map. Differences in presentation of information were evaluated by comparing the boundary indices of the different maps. The suitability map based on the 1:50 000 soil map was the most readable one. Map choice should be based on a consideration by the user of the different quality criteria.
Cotton Response to Residual Fertilizer Potassium on Vermiculitic Soil: Organic Matter and Sodium Effects
Authors: Cassman K. G. , Roberts B. A. , Bryant D. C.
Published: July 2010

Economic return from K addition to soils with a large K‐fixation capacity is largely determined by the residual benefit. To quantify the residual benefit on a vermiculitic soil, wheat (Triticum aestivum L.) was grown in 1988 and cotton (Gossypium hirsutum L.) in 1989 and 1990 in treatments that had received previous fertilizer‐K inputs of 0, 360, 720, and 1440 kg ha−1 from 1985 to 1987. Wheat yield and K uptake were not affected by previous K input levels. In contrast, lint yield of cotton with the highest residual‐K rate increased by 240 to 250 kg ha−1 in 1989 and 1990 (a 22–23% increase) compared with the control without previous K addition. In all years, lint yield was closely correlated with solution‐phase K+ in surface soil although a slow K‐fixation reaction decreased this soil K pool by 23% from 1987 to 1990. This reduction occurred despite net inputs of 85 and 130 kg K ha−1 to cotton in 1989 and 1990, respectively, that were uniformly applied as manure or mineral fertilizer‐K main plots over the existing previous K‐rate treatments, which were subplots. Manure application resulted in a significant increase in soil organic C and reduced the slow fixation of K from the labile pool, compared with equivalent K inputs from mineral fertilizer. Use of moderately saline groundwater for irrigation in the drought years of 1989 and 1990 increased extractable Na from 0.07 cmol kg−1 in 1987 to 1.24 cmol kg−1 in 1990. With increased soil Na, there was a shift in the lint yield response to solution‐phase K+ such that the critical level for maximum yield was reduced. These results demonstrated a large cotton yield response to residual fertilizer K on vermiculitic soils, and this residual benefit was greater with organic‐matter addition. Where Na has been leached from the root zone, a moderate increase in soil Na may reduce the total K requirement due to a Na‐K substitution that is known to maintain cotton yields at lower levels of K supply.
Sorption and Desorption Quantity‐Intensity Parameters Related to Plant‐Available Soil Phosphorus
Authors: Raven K. P. , Hossner L. R.
Published: July 2010

Phosphorus sorption quantity‐intensity (Q/I) relationships have been used more frequently than desorption to assess the capacity of soils to supply P to plants, although desorption properties would seem more appropriate when studying the soil‐plant system since P release is a key feature. The objective of this study was to compare sorption and desorption Q/I parameters as soil P availability indexes. Five soils with diverse chemical and physical properties were enriched with 0, 25, 50, 75, and 100 mg P kg−1. Phosphorus sorption and desorption data were related to corn (Zea mays L.) growth and P uptake results from a greenhouse experiment. The solution P concentration after a given P addition and the corresponding slope of the Q/I curve or P buffering power were used as the sorption intensity and capacity parameters, respectively. The solution P concentration when no P is desorbed by the sample (Io), the magnitude of slope of the Q/I curve at Io or P buffering power at Io, and the maximum desorbed soil P (Qmax) were used as desorption intensity, capacity, and quantity parameters, respectively. Intensity and capacity factors derived from sorption and desorption Q/I curves were not good indicators of the P supplying capacity of soils, but the Qmax was better related to plant growth and P uptake. These results suggest that a specific quantity parameter gained from P desorption Q/I relationships is more useful and meaningful than any parameter obtained from P sorption curves when evaluating the plant‐available P in soils. No simple relationship existed between capacity parameters obtained from sorption and desorption curves.
Crop Rotation and Tillage Effects on Phosphorus Distribution in the Central Great Plains
Authors: Bowman R. A. , Halvorson A. D.
Published: July 2010

The fate and availability of soil P in the central Great Plains may become less predictable with less tillage and more intensive crop rotations that produce more crop residue and litter than conventional‐till (CT) wheat (Triticum aestivum L.)‐fallow (W‐F). We need to evaluate these new systems relative to new P distribution patterns that may be occurring. We determined P changes in a Weld silt loam soil (fine, montmorillonitic, mesic aridic Paleustoll) in predetermined plots from a 5‐year rotation‐tillage experiment where 45 kg P ha−1 was applied in 1990, and 18 kg P ha−1 was applied to the wheat phase of the rotation thereafter. We determined changes in water‐soluble P, resin‐extractable P, total organic P, bicarbonate‐extractable P, and phosphomonoesterase activity as a function of tillage and cropping intensity in soil from the 0‐ to 5‐cm and 0‐ to 15‐cm depths. Phosphorus concentration in wheat tops at an early stage was also determined to assess soil P availability. Generally, P availability indices increased significantly in the 0‐ to 5‐cm depth with continuous cropping treatments compared with wheat‐fallow treatments. The results suggest that under more intensive cropping systems P recycling through residue and litter could be an important mechanism resulting in additional plant‐available P.
Manure Management in an Irrigated Silage Corn Field: Experiment and Modeling
Authors: Ma Liwang , Shaffer M. J. , Ahuja L. R. , Rojas K. W. , Xu C. , Boyd J. K. , Waskom R.
Published: July 2010

On agricultural lands, animal waste disposal as fertilizer has been practiced since the beginning of agriculture. However, the practice has been an environmental concern in recent years due to over disposal of animal waste in some instances. This study evaluated soil NO3 response to beef‐manure application on a corn (Zea mays L.) field and tested the Root Zone Water Quality Model (RZWQM) for manure management. The experiment site was located in Northeastern Colorado on a silage‐corn field with a history of fertilization with beef manure every fall after corn harvest. To study the residual effect of long‐term manure application, 582 kg ha‐1 of manure‐N was applied to the east side of the field in the Fall of 1993, 1994, and 1995, while the west side received manure in 1993 only. Average silage‐corn yields from the west site were 25.4, 31.9, and 22.5 Mg ha‐1 for 1994, 1995, and 1996, respectively, which were not significantly different from that harvested from the east site (25.1, 30.9, and 24.3 Mg ha‐1, respectively). Average soil NO3 concentrations decreased significantly from 14.9 to 8.5 mg N kg‐1 in the top 30 cm of soil, and from 5.4 to 3.7 mg N kg‐1 in the 30‐ to 60‐cm soil profile after stopping manure application. No significant difference in soil NO3 concentrations between the manured and not‐manured sites was found below 60 cm. Average plant N uptake ranged from 140 to 362 kg N ha‐1 and was not significantly different between the two sites. The RZWQM was calibrated on the basis of the measured silage‐corn yield and plant N uptake, and was then used to predict soil NO3 concentration and total water storage in the soil profile. Generally, the calibrated model provided adequate predictions for both NO3 and soil water content with r2 > 0.83. The model was further used to evaluate alternative scenarios of manure and water management.
Tillage Impacts on Depth Distribution of Total and Particulate Organic Matter in Three Illinois Soils
Authors: Wander M. M. , Bidart M. G. , Aref S.
Published: July 2010

The benefits of no‐tillage (NT) practices to soil organic matter (SOM) are inconsistent in fine‐textured, poorly drained soils. Tillage impacts on SOM were investigated in central Illinois, assuming particulate organic matter (POM) would accumulate where SOM aggraded. Soils were collected in 1994 and 1995 from a trial established in 1985 at Perry and Monmouth (somewhat poorly drained Aquic Argiudoll silt loams), and DeKalb (a poorly drained Typic Haplaquoll silty clay loam). In general, NT practices increased SOM‐C and POM‐C contents 25 and 70% compared with conventional till (CT) at the soil surface (0–5 cm). This was at the expense of C at depth (5–17.5 cm), which decreased by 4 and 18%, respectively. Tillage effects varied among sites. No‐till increased SOM C and POM C more than 30 and 100%, respectively, in the top 5 cm of the two silt loams. In the silty clay loam, NT reduced SOM C 14% in the 5‐ to 17.5‐cm depth and POM C more than 20% in the 5‐ to 30‐cm depth. Bulk density was greater under NT than CT at the DeKalb (0–17.5 cm) and Monmouth sites (0–5 cm). No‐till only increased C and N sequestration, assessed on an equivalent mass basis, at Monmouth. Accumulation of POM in the surface depth of the NT silt loams may have improved soil quality in those erosion‐prone soils. Reduced POM contents in the NT silty clay loam may reflect SOM degradation. The high clay and organic matter content and low bulk density of the DeKalb soil may have contributed to the atypical effect of NT practices on SOM at that site.
Comparison of Three Aqua Regia Digestion Methods for Twenty Florida Soils
Authors: Chen Ming , Ma Lena Q.
Published: July 2010

It is important to evaluate different digestion methods to accurately determine elemental concentrations in soils. Three commonly used digestion procedures, hotplate aqua regia, microwave aqua regia, and microwave aqua regia + HF, were compared for digestion of three standard reference materials (SRMs 2704, 2709, and 2711) and 20 Florida soils (three groups of Quartzipsammemts, one group of Alaquods, and one group of Paleudults). Sixteen elements (Al, Ba, Ca, Fe, K, Mg, Mn, P, Zn, As, Cd, Cr, Cu, Ni, Pb, and Se) were analyzed using either an inductively coupled plasma optical emission spectrometer (ICP‐OES) or a graphite furnace atomic absorption spectrophotometer (GFAAS). Precise analysis was achieved for all elements except As (1.0–25%), Cd (1.8–22%), and Se (4.1–22%) in the SRMs using all three procedures, with the microwave aqua regia + HF procedure having slightly better precision (3.7%) averaged across all elements. Compared with the elemental recoveries in SRMs by the microwave aqua regia digestion (80%), microwave aqua regia + HF digestion achieved greater accuracy (94%), whereas the hotplate aqua regia digestion achieved less accuracy (74%). In general, the microwave aqua regia + HF digestion was overall the best procedure for determining concentrations of most metals in SRMs and Florida soils, followed by the microwave aqua regia and the hotplate aqua regia digestion. However, this so‐called total–total digestion procedure (microwave aqua regia + HF) may underestimate total Pb concentration in Florida soils and total Al, Ca, Fe, Mg, and Ba concentrations in the Florida Paleudults.
Aggregate Associated Sulfur Fractions in Long‐Term (>80 Years) Fertilized Soils
Authors: Yang Zhihui , Singh Bal Ram , Hansen Sissel , Hu Zhengyi , Riley Hugh
Published: July 2010

Understanding soil sulfur pools and associated aggregates S fractions can provide a platform for monitoring S dynamics in soils. A long‐term experiment established in 1922 on an Aquic Eutrocryepts in South‐eastern Norway was chosen to investigate the effects of long‐term fertilization on S fractions in bulk soil and those associated with aggregates. Chloroform fumigation‐extraction was used to determine Microbial biomass S (MBS) and the wet chemical analysis method was used to fractionate soil S into ester S (hydriodic acid reducible S), carbon‐bonded S (Raney nickel reducible S) and residual S (Raney nickel non‐reducible S). High farmyard manure (FYM) application resulted in higher MBS in bulk soil than nitrogen + potassium (NK) application, but it did not differ significantly from the control. Application of FYM at 60 Mg ha−1 resulted into accumulation of total S, total organic S and carbon‐bonded S in bulk soils, while mineral fertilizer (nitrogen+phosphorus+potassium+sulfur [NPKS] and NK) and the medium rate of FYM did not increase the accumulation of total S and organic S fractions. The macroaggregate sizes (>2 and 1–2 mm) and the finest aggregate size (<0.106 mm) showed significantly greater total S concentration than other aggregate sizes. Ester S and residual S were predominant organic S fractions and they accounted for 39 to 52% and 38 to 51% of the organic S, respectively. The macroaggregate sizes (>2 and 1–2 mm) contained the highest ester S, but microaggregates (<0.106 mm) exhibited higher carbon‐bonded S and residual S than other aggregates. In conclusion, the accumulation of S was dependent on fertilizer type, the rate of FYM application and aggregate sizes.
Unaccounted for water and the performance of water utilities: an empirical analysis from India
Authors: Kumar Surender
Published: July 2010

Conventional benchmarking measures focus mainly on water produced whilst ignoring water produced but not reaching consumers, unaccounted for water (UFW). Benchmarking must credit utilities for a reduction in UFW and improvements in service delivery. This study measures the performance of 20 urban water utilities using data from an Asian Development Bank survey of Indian water utilities in 2005. It applies directional distance function as an analytical tool for measuring performance of water utilities. The results reveal that at the mean level, Indian water utilities have the potential of increasing water delivery levels and reducing UFW by 20%. About half of that can be realized by changing the scale of operation. Metering of the water delivered and the length of the distribution network are major determinants of performance of water utilities.
Harvesting of Medicinal Plants in the Forest of Central India and its Impact on Quality of Raw Materials: A Case of Nagpur District, India
Authors: Mishra Manish , Kotwal P. C. , Prasad Chandan
Published: July 2010

Adulteration and substitutions are frequent in raw material trade of medicinal plants. Several studies have been done for a number of important crude drug materials to distinguish the genuine material from adulterant. The efficient way to determine adulteration is through morphological and organoleptic studies. The objective of this study is to find out current harvesting methods, malpractices adopted by various stakeholders and ocular analysis of market samples, impacting quality of raw (dry) produce of selected species in market of Nagpur. In the natural forests Baibirang (Embelia ribes Burm.), Safed musli (mixed tubers of Chlorophytum borivilianum Baker, C. tuberosum Baker.), and Aonla (Emblica officinalis Gaertn.) were collected just after the rains at unripe stage. The ocular observations of the market sample of Aonla, Baibirang fruits, Safed musli tubers indicate that mixing of old and diseased parts of same species and other adulterants is rampant in the local market. Laboratory analysis shows that in one kilogram of market sample, more than 20% raw material was found adulterated in all the selected species except Bach (Acorus calamus L.). Most of the selected plants were found adulterated, both intentionally and unintentionally. Major reasons for poor quality are unripe harvesting, mixing of inferior and cheap plant parts, mis-identification of species, non-availability of plant parts in required quantity, etc. Key words: Adulteration, quality, medicinal plants, harvesting, malpractices.  DOI: 10.3126/eco.v16i0.3471ECOPRINT 16: 35-42, 2009
La dimension sociale dans le CECR : pistes pour scénariser, évaluer et valoriser l'apprentissage collaboratif
Authors: Springer Claude
Published: July 2010

Résumé

La « perspective actionnelle » suggère une filiation avec les théories de l'activité, c'est-à-dire une visée socio-culturelle et une visée sociale. Le CECR aborde sans s'attarder cet aspect social en considérant tout locuteur / apprenant dans sa dimension d'acteur social. Dès lors, la « tâche » peut-elle être considérée comme individuelle comme l'approche communicative le laisse entendre ? Comment tenir compte en classe de langues de cette perspective sociale et actionnelle sans retomber dans la tradition de l'apprenant se développant en toute autonomie ? Quelle place accorder, en plus de la compétence de communication, aux compétences dites génériques et transversales qui sont mobilisées nécessairement dans l'action sociale? Comment évaluer et valoriser cette intelligence actionnelle partagée?
NEW MODES AND ORDERS: THE DIFFICULTIES OF A JUS POST BELLUM OF CONSTITUTIONAL TRANSFORMATION
Authors: Bhuta Nehal
Published: July 2010

This article examines the difficulties and dilemmas of the idea of a jus post bellum of constitutional transformation in territories under foreign or international administration. It begins with an argument that, at present, international law contains no such rules and that the law of self-determination provides no guidance. But should international law develop such rules? The balance of the article argues that international law should not prescribe rules or standards for constitution making in such circumstances. En route to this conclusion, it is argued that contractarian understandings of the problem of state making and constitution making are fallacious and that to properly understand the problem of founding new political orders we must conceive of that founding as an aleatory, contingency-riven process of concentrating forms of social and political power within particular territory. Thus, no special premium can be placed on democratic modes of legitimation, and international rules or standards prescribing specific modes of legitimation are likely to be either irrelevant or counter-productive. It is argued, finally, that one of the virtues of international law in these situations is its (relative) agnosticism with respect to different modes of legitimation. It is contended that international law is usefully understood as ‘inter-public law.’ In light of this theory, the structural situation of international law is analogous to the structural position of public law in newly founded domestic political orders. That is, international law is preoccupied with crafting relationships of order across diverse kinds of social and political legitimacy, and its normativity and efficacy are finely balanced between accommodating power and restraining it.
Dates of publication of J.E. Gray'sIllustrations of Indian Zoology(1830–1835)
Authors: WHEELER ALWYNE
Published: July 2010

A brief account is given of J.E. Gray's Illustrations of Indian Zoology, with notes on the sources of the illustrations published, the engravers of the plates and the publishers. The dates of publication of the 16 parts (12 parts of 10 plates each, three double parts of 20 plates each, and one double part of 22 plates) are given from two sources. An index to trivial names of all included taxa is given so that it is possible to identify the part in which the name appears, as well as the number of the plate in bound copies. A brief discussion of the authorship of the new taxa in this work proposes that, with the exception of the testudines (terrapins), all should be attributed to J.E. Gray.
Historic background of Egyptian cotton (2600 BC–AD 1910)
Authors: AMER WAFAA M. , MOMTAZ OSAMA A.
Published: July 2010

The cotton plant was recorded from Egypt in the Dynastic period as early as 2500 BC. Cotton seeds were recovered from Nubia (Egypt) in 1964. Many writers and relief sculptures as well as hieroglyphic symbols confirm cotton cultivation during this period. Cotton cultivation dominated in the Ptolemaic and Roman period (305 BC-AD 395). There were two cotton species (Gossypium arboreum L. and Gossypium herbaceum L.) grown in Egypt during the Islamic period (AD 1477-AD 1711). Later Ashmouni cotton was derived from Sea Island cotton (G. barbadense L. var. maritima Watt); Jumel's cotton (G. brasiliense Macf.) and other Egyptian stocks (possibly G. arboreum and/or G. herbaceum var. africanum (Watt) Hutchinson & Ghose). Ashmouni cotton was the main ancestor of Egyptian cultivare after 1887.
The zoology of the Voyage au pôle sud et dans l'Océanie sur les corvettes I'Astrolabe et la Zélée exécuté par ordre du rol pendant les années 1837–1838 –1839–1840 sous le commandement de M. Dumontd'Urville (1842–1854): titles, volumes, plates, text, contents, proposed dates and anecdotal history of the publication
Authors: CLARK PAUL F. , CROSNIER ALAIN
Published: July 2010

The Atlas d'Histoire Naturelle, Zoologie by Hombron and Jacquinot of the Voyage au pôle sud et dans l'Océanie sur les corvettes l'Astrolabe et la Zélée exécuté par ordre du roi pendant les années 1837–1838–1839–1840 sous le commandement de M. Dumont-d'Urville (1842–1854) comprises 40 plates. These plates were distributed in 28 livraisons published between 1842 and 1854, and their publication dates are unknown. Consequently the indication dates of the new zoological species described in the 3 text volumes, (vol. III: 1853; vol. IV: 1853; vol. V: 1854) have taken priority. But according to the International Code of Zoological Nomenclature (1985), binomial named plates constitute a valid indication. The contents of the 28 livraisons are listed. Although an objective of this present study was to provide publication dates for the Atlas plates, the establishment of precise dates is considered unlikely. This paper proposes that date-stamps on the Atlas in the British Library should be adopted as dates of publication. Evidence supporting this decision is provided, including an anecdotal history of the voyage publication, which generates insight into the reasons for the many delays experienced during the production of the zoology Atlas and descriptive text.
A forgotten theory on the origin of fossils: Daines Barrinaton's concept (1781)
Authors: SARJEANT WILLIAM A. S. , MITCHELL TRENT A.
Published: July 2010

The occurrence in rocks of the remains of creatures, either resembling those still living or distinctively different from them, generated many theories, from a belief that they were relics of the Noachian flood to the concept that they were products of crystallization processes within rocks. Daines Barrington (1727–1800) challenged the idea that they were relics of the flood and instead proposed that they were products of the activity of insects underground.
The dating and correct citation of A. F. A. Wiegmann's “Amphibien” section of Meyen's Reise um die Erde, with a bibliography of Wiegmann's herpetological publications
Authors: BAUER AARON M. , ADLER KRAIG
Published: July 2010

Arend Friedrich August Wiegmann (1802–1841), who was based at Zoologisches Museum in Berlin, is most closely associated with Mexican herpetology through his publication of Herpetologia Mexicana (1834). However, he also made substantial contributions to the study of reptiles and amphibians of other regions, particularly South America and Asia. These were based on collections made by Franz Julius Ferdinand Meyen (1804–1840) on a journey around the world during 1830–1832 and were published as the “Amphibien” section of Meyen's Reise um die Erde. The dating of this work has been especially problematic and several versions of the paper exist. A combination of sources of evidence, both intrinsic and extrinsic to Wiegmann's own publications, strongly suggests that the date of publication of this work is late 1834, that a book version of the paper predated the more widely cited paper in Nova acta, and that all versions of Reise um die Erde postdate Herpetologia Mexicana. An annotated bibliography of Wiegmann's 29 herpetological publications is presented.
Prevalence, Detection, and Management of the Metabolic Syndrome in Patients with Acute Myocardial Infarction: Role of an Obesity-Centric Definition
Authors: Prasad Sandhir B. , Fahrtash Farzan , Malaiapan Yuvaraj , Meredith Ian T. , Cameron James
Published: July 2010

Background. We sought to determine and compare the prevalence of the Metabolic Syndrome (MS) in patients with acute myocardial infarction (AMI) utilizing the new International Diabetes Federation (IDF) definition with the older National Cholesterol Education Program (NCEP) definition. We also examined the clinical utility of MS in this context.Methods. A total of 107 consecutive patients with AMI were prospectively evaluated for MS. Fasting lipids obtained at admission and fasting glucose at discharge were used. A postdischarge folder audit verified rates of discharge coding and implementation of specific management strategies for MS.Results. Baseline patient characteristics included: mean age59±13years; males 80%; diabetes 19%; mean BMI29.7±8.4 kg/m2. MS prevalence was 54% by the IDF definition and 49% by the NCEP definition, with good agreement between definitions:κ=0.664,P<.001. Factors predictive of MS after multivariate analysis included: hypertension, fasting glucose, waist circumference, and serum HDL (allP<.05). Despite the high prevalence, MS was recognized at discharge in only 1 patient, and referral for exercise and/or weight-loss programs was undertaken in 5 patients.Conclusion. There is a high prevalence of MS utilizing contemporary definitions in patients with AMI: 54% by the IDF definition and 49% by NCEP criteria. Despite the high prevalence, MS was under-recognized and under-treated in this population.