bluuebunny/crossref_metadata_2025 huggingface dataset:
Moisture Sensitivity of Cotton Pollen
Authors: Burke John J.
Published: July 2014

Production of cotton (Gossypium hirsutum L.) hybrids is commonly preceded by removing anthers from recipient flowers or interrupting the functioning of the anthers before dehiscence. This study describes the development of an emasculation protocol that did not require removal of the anthers, did not result in female sterility, and maintained fruit retention. Cotton flowers were saturated with water at different times throughout the day. Water sprayed into the flower after the pollen dehisced resulted in the osmotic disruption of the pollen grains and prevented self‐pollination of the cotton flowers. Morphological analysis of isolated pollen grains before and after water treatment showed the exudation of pollen cytoplasm into the surrounding water medium within seconds of the water treatment. The water treatment resulted in the loss of fruiting bodies. Hand pollination of water‐emasculated flowers produced seed numbers equivalent to self‐pollinated controls. To quantify the level of self‐pollination following water emasculation, ‘Gregg 65’ cotton (glandless, recessive trait) was water‐emasculated, the stigma allowed to dry, and the flower pollinated with pollen from ‘Paymaster HS‐26’ cotton (glanded, dominant trait). Evaluation of 66 flowers revealed that 100% of the seedlings obtained from these crosses had the glanded phenotype, thereby showing that no self‐pollination had occurred. In conclusion, this study demonstrates the use of water as an effective emasculation tool for hybrid cotton production that does not result in female sterility and maintains fruit retention and seed set following subsequent pollination with pollen from another flower.
Influence of Rhizobial Inoculation on Photosynthesis and Grain Yield of Rice
Authors: Peng Shaobing , Biswas Jatish C. , Ladha Jagdish K. , Gyaneshwar Prasad , Chen Yizhu
Published: July 2014

Rhizobial inoculation increases grain yield in rice (Oryza sativaL.), a nonlegume plant, but little is known about the mechanism(s) involved. This study was conducted to determine whether inoculation with rhizobia could influence leaf photosynthesis of rice plants under greenhouse conditions. Rice seeds and pot soil were inoculated with three rhizobial strains with or without added N fertilizer. Single‐leaf net photosynthetic rates were measured with portable photosynthesis systems (LI‐6200 and LI‐6400) at several growth stages. Stomatal conductance, chlorophyll fluorescence, specific leaf weight, and leaf N content were also measured. Grain yield and yield components were determined at maturity. A significant increase in single‐leaf net photosynthetic rate by rhizobial inoculation was observed in all three independent experiments. The effect of rhizobial inoculation on photosynthesis was greater in zero‐N than in 90 kg N ha−1treatment. The increase in photosynthetic rate by rhizobial inoculation was 12% averaged across all treatments in the three experiments. The effects of rhizobial inoculation on stomatal conductance, specific leaf weight, and leaf N content were relatively small and less consistent than photosynthetic rate. Chlorophyll fluorescence data suggest that the increase in photosynthetic rate following rhizobial inoculation was not associated with conversion efficiency of light energy in photosystem II. Rhizobial inoculation increased grain yield by 16%. The increase in grain yield was due to an increase in total biomass production rather than harvest index. These results suggest that certain strains of rhizobia can promote rice growth and yield through mechanisms that improve single‐leaf net photosynthetic rate.
Water Depletion Depth of Grain Sorghum and Sunflower in the Central High Plains
Authors: Stone Loyd R. , Goodrum Dwayne E. , Schlegel Alan J. , Jaafar Mahmad Nor , Khan Akhter H.
Published: July 2014

In dryland agriculture of the central High Plains, water is often the primary factor influencing selection of crops and cropping systems. For improved water management, a greater percentage of precipitation during fallow must be stored and used in crop production. More efficient water use can be promoted via agronomic management such as extending the root zone by use of deep‐rooted crops. While sunflower (Helianthus annuus L.) has a reputation for deep rooting, grain sorghum [Sorghum bicolor (L.) Moench] is the dominant dryland row crop in western Kansas. Our objective was to contrast the depth of soil water depletion and end‐of‐season rooting depth of sorghum and sunflower. Rooting depth at end of season was measured by the core‐break method during a 3‐yr study near Tribune, KS, on a Ulysses silt loam soil (fine‐silty, mixed, superactive, mesic Aridic Haplustoll). Water content was measured to the 3.2‐m soil depth by neutron thermalization. The water depletion front advanced downward at greater rates and to deeper depths with sunflower (3.1 m) than with sorghum (2.5 m). Water depletion in the 2.2‐ to 3.3‐m soil depth zone was significantly more for sunflower (48 mm) than for sorghum (14 mm). End‐of‐season rooting depth was significantly greater for sunflower (3.03 m) than for sorghum (2.54 m). The faster advance of the water depletion front and greater depth of rooting of sunflower compared with sorghum are factors contributing to drought avoidance in sunflower and its ability to deplete water from deeper soil depths.
Visualizing Preferential Flow Paths using Ammonium Carbonate and a pH Indicator
Authors: Wang Zhi , Lu Jianhang , Wu Laosheng , Harter Thomas , Jury William A.
Published: July 2014

Despite their negative charge, anionic dyes are less‐than‐ideal tracers of water flow in soil. A new method is presented here for detecting flow patterns faithfully representing the movement of water flow paths in structured and nonstructured soils. The method is based on application of ammonium carbonate during infiltration, which displays a unique color signature when sprayed with a pH indicator after excavation and exposure of the soil profile along a trench face. We compare its performance with that of the popular Brilliant Blue in a laboratory study, and show that it is a more conservative tracer of the water front. We also illustrate its use in a field experiment to detect preferential flow. In contrast to other methods, ammonium carbonate is inexpensive, nontoxic, and leaves negligible residue.
The Neuro‐m Method for Fitting Neural Network Parametric Pedotransfer Functions
Authors: Minasny Budiman , McBratney Alex. B.
Published: July 2014

Parametric pedotransfer functions (PTFs), which predict parameters of a model from basic soil properties are useful in deriving continuous functions of soil properties, such as water retention curves. The common method for deriving parametric water retention PTFs involves estimating the parameters of a soil hydraulic model by fitting the model to the data, and then forming empirical relationships between basic soil properties and parameters. The latter step usually utilizes multiple linear regression or artificial neural networks. Neural network analysis is a powerful tool and has been shown to perform better than multiple linear regression. However neural‐network PTFs are usually trained with an objective function that fits the estimated parameters of a soil hydraulic model. We called this the neuro‐p method. The estimated parameters may carry errors and since the aim is to be able to estimate water retention, it is sensible to train the network to fit the measured water content. We propose a new objective function for neural network training, which predicts the parameters of the soil hydraulic model and optimizes the PTF to match the measured and observed water content, we called this neuro‐m method. This method was used to predict the parameters of the van Genuchten model. Using Australian soil hydraulic data as a training set, neuro‐m predicted the water retention from bulk density and particle‐size distribution with a mean accuracy of 0.04 m3 m−3 The relative improvement of neuro‐m over neural networks that was optimized to fit the parameters (neuro‐p) is 13%. Compared with a published neural network PTF, the new method is 30% more accurate and less biased.
The Influence of Two Surfactants on Infiltration into a Water‐Repellent Soil
Authors: Feng G. L. , Letey J. , Wu L.
Published: July 2014

Water‐repellency which affects infiltration, evaporation, erosion, and other water transfer mechanisms through soil has been observed under several natural conditions throughout the world. Surfactants can be used to mitigate the consequences of soil water repellency. The infiltration rates of two surfactants applied at concentrations of 500, 1000, 3000, and 5000 mg L−1 were measured on laboratory columns of sand treated to create a stable water‐repellent system. All of these surfactant solutions had a surface tension equal to 0.035 N m−1 Drop‐penetration times (DPT) of these solutions were also measured for these solutions. An aqueous ethanol solution with an identical surface tension as the surfactant solutions was also used. The DPT decreased and the infiltration rate increased as the surfactant solution concentration increased. The results are explained by adsorption of surfactant which caused an increase in surface tension of the solution. Adsorption of surfactants enhanced soil rewetting so that treated columns that were dried had high subsequent infiltration rates with water. Because the adsorption of surfactants greatly affects infiltration, prescription of surfactant treatment on a theoretical basis is not feasible. Although some basic concepts can be established, the utility of surfactants in managing water repellent systems will depend on empirical observations.
Water repellency of soils
Authors: Doerr S. H. , Dekker L. W. , Ritsema C. J. , Shakesby R. A. , Bryant R.
Published: July 2014

Adverse effects of soil water repellency (hydrophobicity) are of concern during or following rainfall or irrigation, and are often preceded by conditions of high atmospheric relative humidity (RH). Assessments of repellency are, however, commonly conducted on air‐dried samples at ambient laboratory conditions. This study explores the effects of differing antecedent RHs (32–98%) on the water repellency of air‐dried soils of wide ranging characteristics under laboratory conditions using water drop penetration time (WDPT) and ethanol‐percentage tests. Most samples exhibited considerably higher water repellency after exposure (<1 d) to 98% RH compared with lower RHs, typical of ambient laboratory conditions. This work suggests that previous studies may have incorrectly classified some soils, likely to exhibit water repellency in the field, as wettable, and that tests carried out following exposure of samples to high RH provide assessments that best reflect critical field conditions.
Sorption Strength of Persistent Organic Pollutants in Particle‐size Fractions of Urban Soils
Authors: Krauss Martin , Wilcke Wolfgang
Published: July 2014

The bioavailability of persistent organic pollutants in soils depends on their sorption strength that may vary among different pools. We hypothesized that polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) had different soil organic C‐water partition coefficients (KOC) among particle‐size fractions. We determined the concentrations of 20 PAHs and 12 PCBs in coarse‐sand, fine‐sand, silt, and clay fractions of 11 urban topsoils (0–5 cm). The KOC values were determined using sequential extraction with methanol‐water mixtures (35 and 65% methanol) at 60°C. The ∑20 PAHs concentrations ranged from 0.3 to 186 mg kg−1, the ∑12 PCBs concentrations from 1.2 to 158 μg kg−1 In most soils, the PAH concentrations decreased in the order, silt > clay ≥ fine sand > coarse sand, and those of the PCBs in the order, clay > silt ≥ fine sand > coarse sand. The distribution of PAHs among particle‐size fractions was more heterogeneous than reported in the literature because the soils received PAH‐contaminated wastes (ashes, slags, rubble) with varying texture. In all soils, the proportions of two‐ or three‐ring PAHs decreased with decreasing particle size, indicating that the PAH mixture was increasingly altered. The KOC values of the PAHs were three to 10 times higher than those of the PCBs with similar octanol‐water partition coefficients (KOW). The mean KOC values of all individual PAHs were highest in silt. For all individual PCBs, mean KOC values were highest in clay. The KOC values of PAHs and PCBs varied up to a factor of 100 among the studied soils and particle‐size fractions. Particle‐size fractions with highest PAH and PCB concentrations also showed highest KOC values indicating low bioavailability.
Salinity‐induced Patterns of Natural Abundance Carbon‐13 and Nitrogen‐15 in Plant and Soil
Authors: van Groenigen Jan-Willem , van Kessel Chris
Published: July 2014

Although it is estimated that salinity stress occurs in 50% of irrigated agroecosystems around the world, not much is known about its impact on C and N dynamics. This study was conducted to characterize the impact of salinity stress on natural abundance 13C and 15N (δ13C and δ15N) on a Lethent Clay Loam (fine, smectitic, thermic typic natrargid) in the San Joaquin Valley (California) for a nonhalophyte, C3 plant and soil organic matter (SOM) fractions. A total of 101 plant (Littleseed Canarygrass, [Phalaris minor Retz.]) and soil samples were collected from a 10‐ha area. Electrical conductivity in a 1:5 soil/water paste (EC1:5) ranged from 2.7 to 8.9 dS m−1 The δ13Cplant values varied from −29.8 to −24.0‰, and δ15N from 2.2 to 19.1‰. Average values for δ13C increased from −26.9‰ in the plant, to −25.3‰ in the light fraction (LF) and −24.1‰ in the SOM. Salinity explained 57% of variance in δ13Cplant, 16% of δ13CLF and 6% of δ13CSOM For δ15N, these numbers were 41, 56, and 0%, respectively. There was a clear spatial pattern match between salinity, δ13Cplant, δ15Nplant, and δ15NLF The lack of any salinity‐induced signature in total SOM probably indicates that the salinity was of recent origin. The high positive correlation between salinity and δ15N in crop and LF might be because of higher NH3 volatilization caused by high pH, combined with a relative increase of NH+4‐uptake by the plant under saline conditions. Under certain conditions, δ13C and δ15N signatures of recalcitrant SOM fractions may be used to reconstruct historic salinity patterns.
Biosolids as Nitrogen Source for Irrigated Maize and Rainfed Sorghum
Authors: Binder Darren L. , Dobermann Achim , Sander Donald H. , Cassman Kenneth G.
Published: July 2014

We quantified effects of anaerobically digested sewage sludge (biosolids) on yield, N use efficiency, and soil NO3 over a period of 4 yr. Field experiments with five biosolids rates and six N rates were conducted at two sites on a silty clay loam soil: one with irrigated maize (Zea mays L.) and another site with rainfed sorghum (Sorghum bicolor L.). Biosolids rates for achieving maximum yields in the year of application were 62 Mg ha−1 (441 kg organic N ha−1) on irrigated maize and 36 Mg ha−1 (257 kg organic N ha−1) on rainfed sorghum. At those rates, the increase in relative yield (RY) was 33% in the year of application, 21% in the second year, 14% in the third year, and 9% in the fourth year. Approximately 40, 20, 10, and 5% of the total biosolids‐N was recovered by the crops in the first, second, third, and fourth year, respectively. In irrigated maize, use efficiency of biosolids‐N decreased with increasing biosolids rate, but was similar to that of fertilizer‐N. In rainfed sorghum, use efficiency of biosolids‐N was lower than that of fertilizer‐N. Little NO3 accumulated in soil when biosolids were applied at the recommended rate, but application in excess of that required for maximum yield increased NO3 accumulation in soil. The cumulative N fertilizer value of a biosolids application at the optimal rate was $136 ha−1 for maize and $68 ha−1 for sorghum. Biosolids had a total fertilizer‐N replacement value of $1.9 to 2.2 Mg−1 biosolids. Recommendations for biosolids use should be based on the total N input and its cumulative plant recovery and leaching potential across a 4‐yr period.
Site‐Specific Nitrogen Management of Irrigated Maize
Authors: Ferguson R. B. , Hergert G. W. , Schepers J. S. , Gotway C. A. , Cahoon J. E. , Peterson T. A.
Published: July 2014

Site‐specific N management (SSNM) has been suggested as one means of further increasing the efficiency with which N fertilizers are used and reducing environmental impact. Field studies to evaluate the potential for SSNM to reduce NO3‐N leaching from irrigated maize (Zea mays L.) were conducted from 1994 to 1997. Uniform management (UM) was compared with a SSNM strategy (variable rate technology, VRT) based on an existing N recommendation algorithm for maize using grid sampled soil organic matter and root zone soil residual NO3‐N. A third treatment (reduced variable rate technology, RVRT) evaluated the potential for a reduced rate of N to adequately supply crop N demand when combined with variable rate application. Averaged across all site‐years, there was no significant difference in the total amount of N applied, 142 kg N ha−1 with UM, 141 kg N ha−1 with VRT. Treatment mean grain yields ranged from 4.5 to 13.9 Mg ha−1 and were influenced relatively little by treatment, with VRT yield significantly reduced compared with UM in two site‐years, and UM yield significantly reduced compared with VRT in one site‐year. Treatment mean soil residual NO3‐N in the 0.9‐m root zone ranged from 2.7 to 14.0 mg kg−1, and was low (<6 mg kg−1) for eight site‐years, with no effect of treatment on NO3‐N concentration. For the five site‐years with elevated NO3‐N concentrations (>6 mg kg−1), there were no significant differences between UM and VRT treatments, while RVRT treatment reduced residual NO3‐N for three site‐years. We conclude that the spatial application of the existing recommendation algorithm developed for uniform application may be inappropriate, at least for these sites, and that unique recommendation equations for major soils and climatic regions may be necessary to achieve substantial increases in N‐use efficiency. This study also suggests that improved recommendation algorithms may often need to be combined with methods (such as remote sensing) to detect crop N status at early, critical growth stages followed by carefully timed, spatially adjusted supplemental fertilization to achieve optimum N‐use efficiency.
Dissolved Organic Carbon Retention in Soils
Authors: McCracken Kimberly L. , McDowell William H. , Harter Robert D. , Evans Christine V.
Published: July 2014

Interactions between dissolved organic C (DOC) and mineral soils were examined in a laboratory column study. Specific emphasis was given to comparisons of soil and solution measurements of organic C (OC) retention in four soil parent materials. Soil columns were leached with one of three concentrations of forest floor (FF) leachate or distilled water every third day for 1 yr. The concentration of DOC in solution was analyzed before and after percolation through soil columns to assess net release or retention of DOC. Changes in soil chemical properties (pH, loss‐on‐ignition [LOI], extractable Al and Fe) following leaching were consistent with podzolization. Micromorphological investigation of the soil materials following leaching showed increased accumulation of organo‐metallic coatings in materials treated with high concentrations of DOC relative to distilled water or low concentrations of DOC. The most dramatic changes in soil chemical properties were found in soils leached with high concentrations of DOC. Comparison of solution and soil measures of OC retention indicates that only ∼50% of the DOC lost from solution was measured as soil OC at the end of the experiment. This finding suggests that microbial decomposition is a significant factor regulating OC concentrations in soils and that soil solution data alone do not yield a complete picture of soil OC dynamics.
State‐Space Description of Field Heterogeneity
Authors: Li Hong , Lascano Robert J. , Booker Jill , Wilson L. Ted , Bronson Kevin F. , Segarra Eduardo
Published: July 2014

Field heterogeneity in soil texture and site elevation (SE) may affect crop water and N use. A 2‐yr (1998–1999) study was conducted on the Texas High Plains to determine the interdependence between management (irrigation and N fertilization), soil heterogeneity (texture, soil water, and NO3‐N) and topography, and their impact on cotton (Gossypium hirsutum L.) lint yield and N uptake. Treatments were irrigation at 50 and 75% estimated cotton evapotranspiration (ET) and N rates at 0, 90, and 135 kg ha−1 Soil water content (SWC), lint yield, N uptake, and N fertilizer recovery, measured as a function of management and space, were higher on low positions. Mixed model analysis showed that irrigation was significant on SWC, lint yield, and N uptake (P < 0.05) each year. The N treatment had no effect on lint yield or N uptake in 1998 because of high soil residual NO3‐N, and the model residual was significant for all measured variables (P < 0.0001). Sand, SWC, lint yield, and N uptake were negatively correlated with SE (r ≥ −0.64). In 1998, lint yield, SWC, clay, sand, and SE were cross correlated within 60 to 80 m. Multivariate state‐space analysis showed that lint yield at position i was weighted on lint yield, SWC, clay, sand, and SE at previous position i − 1. It is concluded that 75% ET and N rate at 90 kg ha−1 would be the basis to consider variable water and N rates related to field conditions, and the state‐space model quantified spatial interdependence between irrigation, fertilization, and field heterogeneity.
Crop Sequence and Nitrogen Fertilization Effects on Soil Properties in the Western Corn Belt
Authors: Liebig M. A. , Varvel G. E. , Doran J. W. , Wienhold B. J.
Published: July 2014

Understanding long‐term management effects on soil properties is necessary to determine the relative sustainability of cropping systems. Soil physical, chemical, and biological properties were measured in a long‐term cropping system study in the Western Corn Belt. Properties were evaluated after 16 yr in four crop sequences [continuous corn (zea mays L.) (CC), corn–soybean [Glycine max. (L.)] (C–SB), corn–oat (Avena sativa L.) + clover (80% sweet clover [Melilotus officinalis L.] and 20% red clover [Trifolium pratense L.])–grain sorghum [(Sorghum bicolor (L.) Moench)–soybean (C–OCL–SG–SB), and corn–soybean‐grain sorghum–oat + clover (C–SB–SG–OCL)] each at three N fertilization rates (ZERO, LOW, and HIGH) to a soil depth of 30.5 cm on a Sharpsburg silty clay loam (fine, smectitic, mesic Typic Argiudolls). Nitrogen fertilization had a greater impact on soil properties than crop sequence, with management effects most pronounced at 0 to 7.6 cm. Increased N rate resulted in greater organic C, total N, and particulate organic matter (POM), but lower soil pH. Increased N rate also reduced microbial biomass by ∼20% between the HIGH and ZERO N‐rate treatments. The C–SB–SG–OCL sequence possessed more potentially mineralizable N (PMN) (57 vs. 46 kg ha−1 for average of CC and C–SB) and a higher percentage of POM present as soil organic matter (17.1% for the C–SB–SG–OCL sequence vs. 13.9% for other sequences). Within the context of soil functions and cropping system performance, results from this study indicate the C–SB–SB–OCL sequence enhanced nutrient cycling efficiency, while N fertilization resulted in a trade‐off between its positive effect on biological productivity and negative effect on nutrient cycling efficiency.
Improved design for an automated tension infiltrometer
Authors: Casey Francis X. M. , Derby Nathan E.
Published: July 2014

Automated measurements of water infiltration rates are commonly done using two gage transducers to measure water level changes in the reservoir of an infiltrometer. Previous studies have evaluated and described in detail infiltrometers automated with two gage‐transducers and have shown that measurement precision and accuracy of soil hydraulic properties are improved. A previous study has also suggested the use of a single differential transducer to automate an infiltrometer to eliminate measurement error associated with air bubbles in the infiltrometer reservoir. In this study, the automation of a tension infiltrometer using a differential transducer was developed, evaluated, and applied. A single differential transducer was installed at the bottom of an infiltrometer reservoir and the other end was connected by tubing to the head‐space in the reservoir. Calibration of the reservoir height measurements vs. transducer voltage output was simplified over previous methods and was even demonstrated in situ. Measurement precision was also improved by two orders of magnitude over previous methods. Measurements were also done to demonstrated the use of the single differential transducer set‐up to obtain field measurements of unsaturated hydraulic conductivity and sorptivity. Unlike previous methods though, this method does not allow for the determination of the imposed potential at the soil surface unless adaptations are made.
Cattle Slurry Applied Before Fertilizer Nitrate Lowers Nitrous Oxide and Dinitrogen Emissions
Authors: Stevens R. James , Laughlin Ronald J.
Published: July 2014

Nitrous oxide emissions increase because of denitrification in the first few days after cattle (Bos taurus) slurry (CS) is applied to grassland soils fertilized with NO3 Denitrifying conditions are created when the readily decomposable C in the CS is oxidized by the soil microbial biomass when NO3 is present and O2 is deficient. Half of the readily decomposable C in CS can be volatile fatty acids (VFAs) that take up to 4 d to degrade. The timing of CS application relative to fertilizer‐NO3 application could therefore affect the losses of N2O and N2 We used the 15N gas‐flux method to measure N2O and N2 fluxes from grassland when CS containing 60 kg NH4‐N ha−1 was applied 4, 3, 2, 1, and 0 d before the application of 60 kg N ha−1 of K15NO3 For a field experiment repeated in April, May, August, and October 1998, CS applied 3 or 4 d before KNO3 had no significant effect in any month on the flux of N2O in the 124 h after KNO3 application. On average over all months, the extra emission of N2O‐N over the control was equivalent to 0.8, 1.1, and 2.9% of KNO3‐N for prior applications of CS at 2, 1, and 0 d, respectively. When CS was applied 4 d prior to KNO3 there was no significant effect on the flux of N2 in any month. The maximum loss of N2O + N2 was 8.3% of the KNO3 applied (5 kg N ha−1) when CS and KNO3 were applied at the same time in April.
Soil Organic Carbon Stocks in the Forests of Mount Rainier National Park, Washington
Authors: Totman Michelle E. , Swanson Mark E. , Rodgers Toby M. , McDaniel Paul A. , Rupp Rick A. , Brown David J.
Published: July 2014

Soil organic C represents a substantial component of the total ecosystem C in temperate and boreal forests. We used an isocluster‐driven process of principal components (based on elevation, precipitation, temperature, etc.) to stratify Mount Rainier National Park, a 957‐km2 federal reserve in the state of Washington, for estimating total soil organic C stocks. Eight stratification‐based forest sites for groups of soil pits and vegetation plots were located throughout the park. Average organic C in the park's forest soils (primarily Andisols, Spodosols, and Inceptisols) was 163 Mg C ha−1 (95% confidence interval [CI] = 138–188), and 205.0 Mg C ha−1 (95% CI = 177.9–232.1) with the litter layer included. The low‐elevation Andisols and Spodosols held the greatest per‐hectare stocks. Total ecosystem C stocks, strongly influenced by the live overstory C pool, varied by almost an order of magnitude across plots, ranging from 168 to 1583 Mg C ha−1. Temperature variables, rather than precipitation, were correlated with soil C pools. Site membership accounted for a significant proportion of variance in C stocks, and beta regression indicated that the proportion of total C stored in the soil varied across sites. Additional sampling in the highly variable top 35 cm of the soil significantly improved the precision of estimates for soil C to that depth. The C stocks determined in this study provide baseline data for Mount Rainier National Park and aided in developing a systematic method for resampling to determine flux with time and establishing a basis for a future comparison with adjacent managed forest landscapes.
Method of In‐Line Bromide Breakthrough Curve Measurements for Column Leaching Experiments
Authors: Sobotkova Martina , Snehota Michal
Published: July 2014

This study presents a new method for deriving the breakthrough curve (BTC) of Br− tracer by measurements in the laboratory. In this method, the breakthrough is recorded by an ion selective electrode placed in a flow cell into which a peristaltic pump redirects part of the effluent. Special care was taken to make the measurements insensitive to variations in ionic strength in the effluent by mixing in the ionic strength adjuster. To evaluate this newly proposed method, BTCs of Br− and 2H were measured for two saturated columns during steady‐state flow under ponding boundary conditions. A concentration pulse was generated by the newly developed infiltration head with two independent sets of injection capillaries, which dosed water or tracer solution into the ponding water while keeping the ponding height constant. In addition to the continuous automatic method, discrete samples of effluent were analyzed for Br− by ion chromatography and for 2H using laser spectroscopy. Experiments were conducted on packed sand and on an undisturbed sample of coarse sandy loam soil. In both cases, the results showed good agreement between BTCs of Br− and 2H measured using the proposed method and those derived using traditional methods on effluent samples collected during the same experiment. Additional experiments showed good reproducibility of the BTC measurement during replicated experiments.
Accuracy of Lysimeters for Dissolved Copper, Antimony, Lead, and Zinc Sampling under Small Arms Backstop
Authors: Martel Richard , Castellazzi Pascal , Trépanier Luc , Laporte-Saumure Mathieu , Brochu Sylvie
Published: July 2014

Three assays were conducted to evaluate the reliability of lysimeters in detecting concentrations of Cu, Pb, Sb, and Zn in interstitial water of the vadose zone. Two box lysimeters (BLs) made from polyvinyl chloride (PVC) and polyvinylidene fluoride (PVDF) and three tension lysimeters (TLs) of different types were used. Assays were conducted with two concentrations of dissolved metals, undiluted and diluted in a 1:10 ratio, and at three different pHs. The assays were made to evaluate the sorption induced by the lysimeter material itself, by standard quartz sand added to the BLs, and by two types of glass beads placed around the porous cup of the TLs. Generally, BLs were more suitable for interstitial water sampling than TLs. Among the TLs, the one made of nylon was more reliable than the two others. Box lysimeters are a good choice to obtain accurate and comparable results for Cu, Pb, Sb, and Zn analysis. However, they have to be backfilled with natural soil found at the exact location of the lysimeter and not with standard quartz sand. Nylon TLs can also be used for water sampling for Sb, Pb, and Zn analysis but not for Cu. Glass beads may interact with dissolved metals and their use around the suction cup in TLs can be avoided by using the fine fraction of natural sediments (<125 μm) found at the location of the porous cup. Water samples from TLs do not need to be filtered for dissolved metal analysis because they are already filtered by the porous cup.
Theoretical Relationship between Saturated Hydraulic Conductivity and Air Permeability under Dry Conditions: Continuum Percolation Theory
Authors: Ghanbarian Behzad , Hunt Allen G. , Ewing Robert P. , Skinner Thomas E.
Published: July 2014

The saturated hydraulic conductivity, Ks, is a fundamental characteristic of subsurface flow and the hydrologic cycle. However, direct measurement of Ks is time consuming. Recently, air permeability measurements at 50 and 100 cm of H2O tension, a relatively dry condition in coarse and medium‐textured soils, have been used to estimate Ks. In this short communication, we present a theoretical framework for relating Ks to ka(ϕ), the air permeability as a function of porosity, ϕ, under completely dry conditions. We used power‐law scaling from continuum percolation theory to develop a theoretical relationship between Ks and ka(ϕ). Our result, similar in form to a published logarithmic equation with empirical coefficients, gives a physical interpretation to these empirical coefficients.
Diode laser vaporization of prostate as treatment for benign prostatic enlargement: Initial results of 73 patients with 1 year follow-up
Authors: Acimovic Miodrag , Rafailovic Dragutin , Bumbasirevic Uros , Babic Uros , Santric Veljko , Stanic Miodrag , Dzamic Zoran , Hadzi-Djokic Jovan
Published: July 2014

Objective: Our objective is to evaluate the efficacy, safety and 12 month
outcome of a 980 nm diode laser with Twister fiber in the treatment of benign
prostatic enlargement. Materials and methods: Between February 2011 and
January 2013, 73 patients with benign prostatic enlargement had undergone
diode laser vaporization of prostate at our institution. The following
parameters were assessed at baseline, and after a follow-up period of 3 and
12 months: International Prostate Symptom Score, peak urinary flow rate,
post-void residual urine volume, and quality of life score. Results: The
procedure was completed successfully in all patients with no intraoperative
complications. At 12 months postoperatively the percentage improvements in
IPSS was-69.09%, Qmax +197%, PVR-88.54%, and QoL-68.29%. Conclusion: Diode
laser vaporization of prostate is safe and effective method for treatment of
benign prostatic enlargement.
Complications associated with Percutaneous nephrolitholapaxy (PCNL): Our experience and literature review
Authors: Nikic Predrag , Durutovic Otas , Kajmakovic Boris , Nale Djordje , Bumbasirevic Uros , Radovanovic Milan , Milenkovic-Petronic Dragica , Dzamic Zoran
Published: July 2014

Background: PCNL is safe procedure which is well tolerated, but as with any
other surgical procedure, it is associated with a specific set of
complications. There is a marked heterogeneity in reporting complication
rates in literature, and this problem was highlighted in Ad Hoc EAU
guidelines panel who recommended urgent creation of uniform and reproducible
quality system. Modified Dindo-Clavien grading system today is the most
utilized classification for complications in urology, and standard in
reporting complications for PCNL. Aim(s): To analyze the complication rate
for PCNL using the modified Dindo-Clavien grading system in our patients and
literature review. Methods: In our institution, with few breaks, PCNL was
performed since mid 2010. Complication rate in 63 patients was analyzed
retrospectively. Modified Dindo-Clavien grading system that is validated for
PCNL has been accepted for classification of complication for PCNL, and
literature review was performed. We have summarized the most significant
factors which may affect the complication rate during and after PCNL. Results
: Overall complication rate was 30% in our study population. The most common
complications observed were: postoperative fever Grade1-2 (9.52%) and
bleeding Grade1 (7.9%), Grade2 (3.17%), Grade3a (4.76%) and Grade3b (1.58%).
Nephrostomy tube leakage was not found in our sample, mostly due to specific
postoperative utilizing of auxiliary procedures. Conclusion: Reporting of
complication for PCNL should be uniform, and modified Dindo-Clavien grading
system that is validated for PCNL should be accepted to be a standard in
urology. Surgeons training and experience are the most important to ensure
the efficacy of procedure, therefore we suggest that learning of percutaneous
renal access should be mandatory in residents trainee program.
Orthotopic urinary diversion after radical cystectomy in treatment of muscle invasive bladder cancer
Authors: Hadzi-Djokic Jovan , Andrejevic Vladan , Pejcic Tomislav , Acimovic Miodrag , Babic Uros , Stanic Miodrag , Dzamic Zoran
Published: July 2014

Surgical treatment of invasive carcinoma of the bladder in males includes
total cystectomy remo?al of the prostate, seminal vesicles, and the distal
parts of the urethers and the pelvic lymph node dissection as well. At this
moment it is not possible to recommend a particular type of urinary
diversion, but today in clinical practice commonly used derivative are ileal
orthotopic neobladder as the continent one and ileal conduit as non-continent
urinary diversion. Continent urinary diversion after radical cystectomy are
the result of the application of technological innovation in surgery, but
also knowledge, imagination and skill of well trained urologist. This type of
operation significantly improves the quality of life in patients who
underwent radical cystectomy, and the proposal is to operate when- ever there
is a possibility for this type of procedure. Also it is very important,
during surgery to respect oncological principles, of complete removal of
tumorous tissue and that the functional principle of ensuring that the
patients have daytime and also nighttime continence later on after the
surgery.
Trans-Oturator-Tape (T.O.T.) "outside-in" approach in surgical treatment of female stress urinary incontinence
Authors: Jovanovic M. , Dzamic Zoran , Acimovic Miodrag , Kajmakovic Boris , Pejcic Tomislav
Published: July 2014

Objective: The aim of the study was to analyzed the efficacy and safety of a
minimally invasive surgical procedure using the Trans-Obturator-Tape with
"outside-in" approach for treatment female stress urinary incontinence.
Patients and Methods: 171 women with stress urinary incontinence (SUI)
associated with urethral hypermobility, underwent the T.O.T. procedure (March
2010 to January 2014). 27 patients were previously operated for incontinence.
Mean age was 59 years (37-80). 6 patients were having mixed incontinence, and
51 had SUI with urgencies. A non-elastic, polypropylene tape was placed under
the mid-urethra. The surgical placement technique utilises a trans -
obturator percutaneous approach. All patients underwent post-operative
clinical examination, cough-stress test (full bladder), uroflowmetry, and
post-voiding residual assessment. Results: Mean follow-up was 22 months
(4-45). At 12 months follow-up 91,2% of the patients were completely cured.
The overall peri-operative complication rate was 6,4% with no vascular, nerve
or bowel injury. 5 patients (2,9%) had post-operative urinary retention.
Conclusion: The present study confirms the results obtained by the instigator
of the technique, E. Delorme, and allows us to consider T.O.T. as an
effective and safe technique for the treatment of female stress urinary
incontinence.
Etiopathogenesis, diagnostics and history of surgical treatment of stress urinary incontinence
Authors: Hadzi-Djokic Jovan , Babic Uros , Argirovic Aleksandar , Acimovic Miodrag , Radovanovic Milan , Milojevic Bogomir , Pejcic Tomislav , Dzamic Zoran
Published: July 2014

Urinary incontinence represents involuntary urine leakage into the urethra.
This pathological condition represents a major medical, social and hygienic
problem. The paper presents risk factors for development of the disorder, as
well as diagnostic methods applied in evaluation of the female patients.
Chronological review of diverse surgical techniques used in treatment of
stress urinary incontinence reported in the published scientific papers is
also presented. Review of the literature data was also per- formed. Sling
procedures with application of suburethral loops have been used since the
beginning of the last century in treatment of this disorder. Surgical
treatment of stress urinary incontinence is applied when conservative
treatment fails to give any effects according to strictly defined
indications. During the last 100 years, surgical techniques have undergone
different improvements and the results have also been significantly improved.
Management of penile trauma caused by a dog bite
Authors: Acimovic Miodrag , Babic Uros , Argirovic Aleksandar , Acimovic Ljubomir , Santric Veljko , Bumbasirevic Uros , Rafailovic Dragutin , Kajmakovic Boris
Published: July 2014

Background: Dog bites to the external genitalia are extremely rare. The
literature shows only sporadic cases of penile injuries due to dog bites,
presenting mostly as children and adolescents. Case presentation: We report
the case of a 45-year old patient with avulsion and traumatic degloving of
the penile skin, with exposure of the tunica albuginea, which surrounds the
cavernous bodies. Conclusion: Dog bite wounds pose a serious medical threat.
An effective initial treatment of the wound, as well as adequate supportive
treatments are essential for the efficient healing of the resulting
infection.
A case report of the first laparoscopic radical nephrectomy done at the Clinic of urology, Clinical centre of Serbia
Authors: Kajmakovic B.M. , Dzamic Z.M. , Dragicevic S. , Acimovic Miodrag , Milojevic Bogomir , Hadzi-Djokic Jovan
Published: July 2014

Laparoscopic interventions are at the very beginning of its evolution in the
Clinic of Urology. The first steps have been made primarily to cope with
problem of varicocele. We continued to gain laparoscopic experience by
switching to solving some demanding intervention, primarily kidney cyst. The
only logical next step lead to laparoscopic renal surgery. So, after a few
successful primary simple nephrectomy, the next step was to perform a
laparoscopic radical nephrectomy. Today, at the Clinic of Urology, Clinical
Center of Serbia we successfully perform much more demanding interventions,
such as extraperitoneal laparoscopic radical prostatectomy. In this paper we
present our experience with the first laparoscopic radical nephrectomy, which
was done at the Clinic of Urology, Clinical Center of Serbia.
Diagnostic and therapeutic protocol in the treatment of hypo functional kidney
Authors: Kajmakovic B.M. , Dzamic Z.M. , Dragicevic S. , Acimovic Miodrag , Milojevic Bogomir , Hadzi-Djokic Jovan
Published: July 2014

Laparoscopic nephrectomy is indicated in the treatment of many benign
conditions of the kidneys. Hydronephrosis caused by obstruction of the
ureter, either internal, or external, is one of the main indications for
laparoscopic reconstruction. If an obstruction is prolonged, consequently, it
leads to chronic inflammatory process accompanied by persistent and recurrent
pain with fever, which eventually become resistant to therapy. If not
operated sufficiently fast to resolve the causes, as a consequence it leads
to hypofunction and ultimately afunction of affected kidney. In such a
situation, the only therapeutic option is surgical treatment. By analyzing
the case, we will try to illustrate the diagnostic algorithm and therapeutic
treatment modality.
Concentrations of stromal cell-derived factor-1 in serum, plasma, and synovial fluid of horses with osteochondral injury
Authors: Dymock David C. , Brown Murray P. , Merritt Kelly A. , Trumble Troy N.
Published: July 2014

Objective—To determine whether stromal cell-derived factor-1 (SDF-1) concentrations in serum, plasma, and synovial fluid differed among untrained, race-trained, and osteochondral-injured Thoroughbred racehorses.

Animals—22 racehorses without osteochondral injury and 37 racehorses with osteochondral injury.

Procedures—Horses without osteochondral injury were examined before and after 5 to 6 months of race training. Horses with osteochondral injury were undergoing arthroscopic surgery for removal of osteochondral fragments from carpal or metacarpophalangeal or metatarsophalangeal joints (fetlock joints). Serum, plasma, and fetlock or carpal synovial fluid samples were obtained and analyzed for SDF-1 concentration by use of an ELISA.

Results—In horses with fetlock or carpal joint injury, mean synovial fluid SDF-1 concentrations were significantly higher, serum SDF-1 concentrations were significantly lower, and synovial fluid-to-serum SDF-1 ratios were significantly higher than in untrained and trained horses. Synovial fluid SDF-1 concentrations were not significantly different between trained and untrained horses. Plasma SDF-1 concentrations were not different among the 3 groups. Results obtained with serum, compared with synovial fluid and plasma, had better sensitivity for differentiating between osteochondral-injured horses and uninjured horses. In horses with fetlock joint osteochondral injury, serum SDF-1 concentrations were correlated with radiographic and arthroscopic inflammation scores, but not arthroscopic cartilage scores.

Conclusions and Clinical Relevance—Results suggested that serum SDF-1 concentrations were more sensitive than plasma and synovial fluid concentrations for detection of osteochondral injury in the fetlock or carpal joint of racehorses. Analysis of serum and synovial SDF-1 concentrations in horses with experimentally induced joint injury may help define the onset and progression of post-traumatic osteoarthritis and aid in the evaluation of anti-inflammatory treatments.
Evaluation of tranexamic acid and ϵ-aminocaproic acid concentrations required to inhibit fibrinolysis in plasma of dogs and humans
Authors: Fletcher Daniel J. , Blackstock Kelly J. , Epstein Kira , Brainard Benjamin M.
Published: July 2014

Objective—To determine minimum plasma concentrations of the antifibrinolytic agents tranexamic acid (TEA) and ϵ-aminocaproic acid (EACA) needed to completely inhibit fibrinolysis in canine and human plasma after induction of hyperfibrinolysis.

Samples—Pooled citrated plasma from 7 dogs and commercial pooled citrated human plasma.

Procedures—Concentrations of EACA from 0 μg/mL to 500 μg/mL and of TEA from 0 μg/mL to 160 μg/mL were added to pooled citrated canine and human plasma. Hyperfibrinolysis was induced with 1,000 units of tissue plasminogen activator/mL, and kaolin-activated thromboelastography was performed in duplicate. The minimum concentrations required to completely inhibit fibrinolysis 30 minutes after maximum amplitude of the thromboelastography tracing occurred were determined.

Results—Minimum plasma concentrations necessary for complete inhibition of fibrinolysis by EACA and TEA in pooled canine plasma were estimated as 511.7 μg/mL (95% confidence interval [CI], 433.2 to 590.3 μg/mL) and 144.7 μg/mL (95% CI, 125.2 to 164.2 μg/mL), respectively. Concentrations of EACA and TEA necessary for complete inhibition of fibrinolysis in pooled human plasma were estimated as 122.0 μg/mL (95% CI, 106.2 to 137.8 μg/mL) and 14.7 μg/mL (95% CI, 13.7 to 15.6 μg/mL), respectively.

Conclusions and Clinical Relevance—Results supported the concept that dogs are hyperfibrinolytic, compared with humans. Higher doses of EACA and TEA may be required to fully inhibit fibrinolysis in dogs.