bluuebunny/crossref_metadata_2025_split huggingface dataset:
Agricultural Dust Production in Standard and Conservation Tillage Systems in the San Joaquin Valley
Authors: Baker J. B. , Southard R. J. , Mitchell J. P. 
Published: July 2005

ABSTRACTThe negative health effects of repeated dust exposure have been well documented. In California's San Joaquin Valley, agricultural operations may contribute substantially to airborne particulates. We evaluated four management systems to assess impacts on dust production and soil properties for a cotton (Gossypium hirsutum L.)–tomato (Lycopersicon esculentum Mill.) rotation: standard tillage with (STCC) and without (STNO) cover crop, and conservation tillage with (CTCC) and without (CTNO) cover crop. Gravimetric analysis of total dust (TD, <100‐μm aerodynamic diameter) and respirable dust (RD, 4‐μm aerodynamic diameter) samples collected in the plume generated by field implements showed that dust concentrations for CTNO treatments were about one‐third of their STNO counterparts for both cumulative TD and RD measured throughout the two‐year rotation, primarily due to fewer in‐field operations. The TD and RD production for STNO and STCC was comparable, whereas the CTCC system produced about twice as much TD and RD as CTNO. Energy dispersive spectroscopy (EDS) analyses showed absolute increases of 8 and 39% organic fragments in STCC and CTCC over STNO and CTNO, respectively, while organic fragments in the TD increased by 6% in both cover crop treatments. Soil C content was positively correlated with clay content and increased by an average of 0.12 and 0.07% in the cover crop and non‐cover crop treatments, respectively, although soil C for each treatment showed a distinct response to a field texture gradient. While dust emissions show an immediate decrease due to fewer field operations for the conservation tillage treatments, long‐term sampling is necessary to determine the effects that increased aggregation through organic matter additions may have on dust production.
Fertilizer, Tillage, and Dairy Manure Contributions to Nitrate and Herbicide Leaching
Authors: Stoddard C. S. , Grove J. H. , Coyne M. S. , Thom W. O. 
Published: July 2005

ABSTRACTFew studies have examined the water quality impact of manure use in no‐tillage systems. A lysimeter study in continuous corn (Zea maysL.) was performed on Maury silt loam (fine, mixed, semiactive, mesic Typic Paleudalf) to evaluate the effect(s) of tillage (no‐till [NT] and chisel‐disk [CD]), nitrogen fertilizer rate (0 and 168 kg N ha−1), and dairy manure application timing (none, spring, fall, or fall plus spring) on NO3–N, atrazine (2‐chloro‐4‐ethylamino‐6‐isopropylamino‐s‐triazine), and alachlor [2‐chloro‐2′‐6′‐diethyl‐N‐(methoxymethyl)acetanilide] concentrations in leachate collected at a 90‐cm depth. Herbicides were highest immediately after application, declining to less than 4 μg L−1in about two months. Manure and manure timing by tillage interactions had little effect on leachate herbicides; rather, the data suggest that macropores rapidly transmitted atrazine and alachlor through the soil. Tillage usually did not significantly affect leachate NO3–N, but no‐tillage tended to cause higher NO3–N. Manuring caused higher NO3–N concentrations; spring manuring had more impact than fall, but fall manure contained about 78% of the N found in spring manure. Nitrate under spring “only fertilizer” treatment exceeded 10 mg L−138% of the time, compared with 15% for spring only manure treatment. After three years, manured soil leachate NO3–N exceeded that for soil receiving only N fertilizer. Soil profile (90 cm) NO3–N after corn harvest exceeding 22 kg N ha−1was associated with winter leachate NO3–N greater than 10 mg N L−1Manure can be used effectively in conservation tillage systems on this and similar soils. Accounting for all N inputs, including previous manure applications, will be important.
Physicochemical Characteristics of Animal and Municipal Wastes Decomposed in Arid Soils
Authors: Fares Farouk , Albalkhi Akram , Dec Jerzy , Bruns Mary Ann , Bollag Jean‐Marc 
Published: July 2005

ABSTRACTThe application of anaerobically processed animal manure to maintain adequate levels of organic matter in arid soils is becoming a common practice. The purpose of this study was to characterize two farm manure products as compared with municipal waste compost (MWC). The anaerobic processing to obtain a biogas manure (BM) product was much faster (25 d) than the aerobic composting of farmyard manure (FYM) (90 d). Drying by three different methods (solar‐drying, vacuum‐drying at 45°C, and freeze‐drying) did not affect the quality of BM. Based on the chemical characteristics, FYM and BM products were comparable, and, containing less ash (30%) and heavy metals (50 mg Pb kg−1), seemed superior to MWC that contained 65% ash and 108 mg Pb kg−1On the other hand, MWC had higher C content (69.9%), lower acidity (15.04 mol kg−1), and higher exothermic peaks (300–460°C) than BM and FYM (50% C, 20 mol kg−1, and 275–450°C, respectively), thus showing a greater extent of humification. Also, when the organic materials were incubated with arid soils and monitored for mean residence times (MRT), MWC was slightly more resistant to decomposition (MRT 175–180 d) than BM or FYM (MRT 161–166 d). The observed differences, however, were too small to dismiss any of the products as a valuable material for land applications to improve soil quality. In view of the results obtained, MWC may be considered an adequate substitute for BM or FYM, whenever the latter are in short supply.
Surface Runoff and Transport of Sulfonamide Antibiotics and Tracers on Manured Grassland
Authors: Burkhardt Michael , Stamm Christian , Waul Christopher , Singer Heinz , Müller Stephan 
Published: July 2005

ABSTRACTDespite their common use in animal production the environmental fate of the veterinary sulfonamide antibiotics after excretion is only poorly understood. We performed irrigation experiments to investigate the transport of these substances with surface runoff on grassland. Liquid manure from pigs treated with sulfadimidine was spiked with sulfadiazine, sulfathiazole, the herbicide atrazine (2‐chloro‐4‐ethylamino‐6‐isopropylamino‐1,3,5‐triazine), and the conservative tracer bromide and spread onto eight plots. Four plots received the same amounts of the spiked substances in aqueous solution (controls). Apart from the application matrix we varied the time between application and irrigation. Manure increased the runoff volume up to six times compared with the controls. It seemed that manure enhanced the runoff by sealing the soil surface. On manured plots the relative antibiotic concentrations in runoff were higher than on the controls, reaching an average of 0.3% (sulfadiazine), 0.8% (sulfathiazole), and 1.4% (sulfadimidine) of the input concentrations after a 1‐d contact time. The corresponding values on the controls were 0.16% for sulfadiazine and 0.08% for sulfathiazole. After 3 d, the maximum values on the manured plots were even higher, whereas they had fallen below the limit of quantification on the controls. As a consequence, the sulfonamide losses were 10 to 40 times larger on the manured plots. The relative mobility of the sulfonamides on the control plots followed the trend expected from their chromatographic separation but the opposite was found on the manured plots. Hence it is important to consider explicitly the physical and chemical effects of manure when assessing the environmental fate of sulfonamides.
Quantification of Intrinsic Water Use Efficiency along a Moisture Gradient in Northeastern China
Authors: Yu Mei , Xie Yichun , Zhang Xinshi 
Published: July 2005

ABSTRACTWater use efficiency (WUE) is an important ecophysiological characteristic of plants, especially in semiarid and arid regions. At the scale of community or ecosystem, WUE is difficult to quantify because the amount of water used per unit dry mass production is a function of microclimatic variables and species composition. In this study, we analyzed corrected intrinsic water use efficiency (IWUEs) of grass and shrub species along the western segment of the Northeast China Transect (NECT) and the relationship between IWUEs and mean annual rainfall, habitat degradation status, vegetation type, and plant functional type (C3 versus C4) at 22 survey sites. Site intrinsic water use efficiency (IWUEv) and its relationship with the aforementioned site variables were analyzed based on species frequencies at each site. First, it was concluded that photosynthetic pathway played a very important role in determining species IWUEs Mean IWUEs for C4 species was approximately double that of C3 species. Second, mean annual rainfall, vegetation type, and site degradation status significantly affected IWUEs (p < 0.01). Mean IWUEs at degraded sites was twice as high as that at nondegraded sites. The mean IWUEs for meadows was significantly higher than those for other vegetation types (p < 0.05). Third, the frequency of occurrence of C4 plants explained 36% of the variance in IWUEv across the survey sites. The mean frequency of C4 occurrence at degraded sites was more than double that at nondegraded sites. Consequently, mean IWUEv at degraded sites was more than double that at nondegraded sites. Dominant C4 species in saline–alkaline areas tended to have higher intrinsic WUE than dominant C4 species in sandy shrub communities.
Visible‐Near Infrared Reflectance Spectroscopy for Rapid, Nondestructive Assessment of Wetland Soil Quality
Authors: Cohen Matthew J. , Prenger Joseph P. , DeBusk William F. 
Published: July 2005

ABSTRACTRecent evidence supports using visible‐near infrared reflectance spectroscopy (VNIRS) for sensing soil quality; advantages include low‐cost, nondestructive, rapid analysis that retains high analytical accuracy for numerous soil performance measures. Research has primarily targeted agricultural applications (precision agriculture, performance diagnostics), but implications for assessing ecological systems are equally significant. Our objective was to extend chemometrics for sensing soil quality to wetlands. Hydric soils posed two challenges. First, wetland soils exhibit a wider range of organic matter concentrations, particularly in riparian areas where levels range from <1% in sedimentation zones to >90% in backwater floodplains; this may mute spectral responses from other soil fractions. Second, spectral inference of cation concentrations in terrestrial soils is for oxidized species; under reducing conditions in wetlands, oxidation state variability is observed, which strongly affects chroma. Riparian soils (n = 273) from western Florida exhibiting substantial target parameter variability were compiled. After minimal pre‐processing, soils were scanned under artificial illumination using a laboratory spectrometer. A multivariate data mining technique (regression trees) was used to relate post‐processed reflectance spectra to laboratory observations (pH, organic content, cation concentrations, total N, C, and P, extracellular enzyme activity). High validation accuracy was generally observed (r2validation > 0.8, RPD > 2.0, where RPD is the ratio of the standard deviation of an attribute to the observed standard error of validation); where accuracy was lower, categorical models (classification trees) successfully screened samples based on diagnostic functional thresholds (validation odds ratio > 10). Graphical models verified significant association between predictions and observations for all parameters, conditioning on biogeochemical covariates. Visible‐near infrared reflectance spectroscopy offers both cost and statistical power advantages; hydric conditions do not appear to constrain application.
Phosphorus Leaching in Sandy Outwash Soils following Potato‐Processing Wastewater Application
Authors: Zvomuya Francis , Gupta Satish C. , Rosen Carl J. 
Published: July 2005

ABSTRACTLand application of wastewater presents potential for ground water pollution if not properly managed. In situ breakthrough tests were conducted using potato (Solanum tuberosum L.)–processing wastewater and a Br tracer to characterize P leaching in seasonally frozen sandy outwash soils. In the first test, P and Br breakthrough were measured in a 7‐m deep well following wastewater [2.94 mg L−1 total P (TP); 280 mg L−1 Br] application at the site that had 13.1 mg water‐extractable P (WEP) kg−1and 94.4 mg Bray‐1 P kg−1 Bromide was detected in the well after ∼0.4 pore volumes, but there was no P break‐through after 7 pore volumes. In the second breakthrough test, wastewater containing 3.6 mg L−1 TP and 259 mg L−1 Br was applied on 1.5‐m deep lysimeters at low (0.8 mg WEP kg−1; 12.1 mg Bray‐1 P kg−1) and high soil test P sites (104 mg WEP kg−1; 585 mg Bray‐1 P kg−1). Leachate TP concentration during the test remained constant (0.04 mg L−1) at the low P sites but increased from ∼3.5 to 5.6 mg L−1 at the high P sites. These results indicate no P leaching in low P soils, but leaching in high P soils, thus suggesting that most of the P leached at the high P sites was mainly due to desorption and dissolution of weakly adsorbed P from prior P applications. This was consistent with P transport simulations using the convective–dispersive equation. We conclude that P concentration in land‐applied wastewater should be regulated based on soil test‐P level plus wastewater P loading.
Predicting Dissolved Phosphorus in Runoff from Manured Field Plots
Authors: Vadas P. A. , Haggard B. E. , Gburek W. J. 
Published: July 2005

ABSTRACTDissolved inorganic P transport in runoff from agricultural soils is an environmental concern. Models are used to predict P transport but rarely simulate P in runoff from surface‐applied manures. Using field‐plot data, we tested a previously proposed model to predict manure P in runoff. We updated the model to include more data relating water to manure ratio to manure P released during water extractions. We verified that this update can predict P release from manure to rain using published data. We tested the updated model using field‐plot and soil‐box data from three manure runoff studies. The model accurately predicted runoff P for boxes, but underpredicted runoff P for plots. Underpredictions were caused by runoff to rain ratios used to distribute P into runoff or infiltration. We developed P distribution fractions from manure water extraction data to replace runoff to rain ratios. Calculating P distribution fractions requires knowing rainfall rate and times that runoff begins and rain stops. Using P distribution fractions gave accurate predictions of runoff P for soil boxes and field plots. We observed relationships between measured runoff to rain ratios and both P distribution fractions and a degree of error in original predictions, calculated as (measured runoff P/predicted runoff P). Using independent field‐plot data, we verified that original underpredictions of manure runoff P can be improved by calculating P distribution fractions from measured runoff to rain ratios or adjusting runoff to rain ratios based on their degree of error. Future work should test the model at field or watershed scales and at longer time scales.
Soil Redistribution Model for Undisturbed and Cultivated Sites Based on Chernobyl‐Derived Cesium‐137 Fallout
Authors: Hrachowitz Markus , Maringer Franz‐Josef , Steineder Christian , Gerzabek Martin H. 
Published: July 2005

ABSTRACTMeasurements of 137Cs fallout have been used in combination with a range of conversion models for the investigation of soil relocation mechanisms and sediment budgets in many countries for more than 20 yr. The objective of this paper is to develop a conversion model for quantifying soil redistribution, based on Chernobyl‐derived 137Cs. The model is applicable on uncultivated as well as on cultivated sites, taking into account temporal changes in the 137Cs depth distribution pattern as well as tillage‐induced 137Cs dilution effects. The main idea of the new model is the combination of a modified exponential model describing uncultivated soil with a Chapman distribution based model describing cultivated soil. The compound model subsequently allows a dynamic description of the Chernobyl derived 137Cs situation in the soil and its change, specifically migration and soil transport processes over the course of time. Using the suggested model at the sampling site in Pettenbach, in the Austrian province of Oberösterreich 137Cs depth distributions were simulated with a correlation coefficient of 0.97 compared with the measured 137Cs depth profile. The simulated rates of soil distribution at different positions at the sampling site were found to be between 27 and 60 Mg ha−1 yr−1 It was shown that the model can be used to describe the temporal changes of 137Cs depth distributions in cultivated as well as uncultivated soils. Additionally, the model allows to quantify soil redistribution in good correspondence with already existing models.
Influence of Canola and Sunflower Diet Amendments on Cattle Feedlot Manure
Authors: Hao Xiying , Mir Priya S. , Shah Mohammad A. , Travis Greg R. 
Published: July 2005

ABSTRACTCattle (Bos taurus) producers can replace a part of the traditional diet of barley (Hordeum vulgare L.) grain/silage with sunflower (Helianthus annus L.) seeds or canola meal (Brassica napus L.)/oil to enhance conjugated linoleic acids (CLA) content in milk and meat for its positive health benefits. The objective of this study is to investigate the effects of feeding sunflower or canola to finishing steers on cattle manure chemical properties and volatile fatty acid (VFA) content. The control diet contained 84% rolled barley and 15% barley silage, which provided only 2.6% lipid. The other six treatments had 6.6 to 8.6% lipid delivered from sources such as hay, sunflower seed (SS), canola meal/oil, and SS forage pellets. Manure samples (a mixture of cattle urine, feces, and woodchip bedding materials) were collected and analyzed after cattle had been on these diets for 113 d. The dietary source and level of lipid had no effect on organic N and nitrate N content in manure, but significantly affected ammonia N and VFA. Inclusion of SS forage pellets, hay, or canola meal/oil in cattle diets had no significant impact on manure characteristics, but SS significantly reduced the pH and increased propionic, isobutyric, and isovaleric content. In addition, N loss after excretion (mainly from urine N) increases with the pH and N levels in both feed and manure. The combination of SS with barley silage resulted in a lower VFA and NH3 content in manure and should be a more attractive option. To better manage N nutrient cycles and reduce NH3 related odor problems, feed and manure pH should be one of the factors to consider when determining feed mix rations.
Maximum Rates of Nitrate Removal in a Denitrification Wall
Authors: Schipper Louis A. , Barkle Gregory F. , Vojvodic‐Vukovic Maja 
Published: July 2005

ABSTRACTDenitrification walls are constructed by mixing a carbon source such as sawdust into soils through which ground water passes. These systems can reduce nitrate inputs to receiving waters by enhancing denitrification. Maximum rates of nitrate removal by denitrification need to be determined for design purposes. To determine maximum rates of nitrate removal we added excess nitrate (50 mg N L−1) to a trench up‐gradient of a denitrification wall during a 9‐d trial. Bromide (100 g L−1) was also added as a conservative tracer. Movement of nitrate and bromide was measured from shallow wells and soil samples were removed for measurements of denitrification, carbon availability, nitrate, and other microbial parameters. Rates of nitrate removal, determined from the ratio of NO3–N to Br and ground water flow, averaged 1.4 g N m−3 of wall d−1 and were markedly greater than denitrification rates determined using the acetylene block technique (average: 0.11 g N m−3 of wall d−1). These nitrate removal rates were generally lower than reported in other denitrification walls. Denitrification rates increased when nitrate was added to the laboratory incubations, indicating that despite large nitrate inputs in the field, denitrification remained limited by nitrate. This limitation was partially attributed to nitrate predominantly moving through zones of greater hydraulic conductivity or in the mobile fraction of the ground water and slow diffusion to the immobile fraction where denitrifiers were active.
Disturbance of Water‐Extractable Phosphorus Determination by Colloidal Particles in a Heavy Clay Soil from the Netherlands
Authors: Koopmans G. F. , Chardon W. J. , van der Salm C. 
Published: July 2005

ABSTRACTWater extraction methods are widely used to extract phosphorus (P) from soils for both agronomic and environmental purposes. Both the presence of soil colloids in soil water filtrates, and the contribution of colloidal P to the molybdate‐reactive phosphorus (MRP) concentration measured in these filtrates, are well documented. However, relatively little attention has been given to the direct disturbance by colloids of MRP measurement. The objective of this paper is to show this influence found for water extracts with a soil to solution ratio of 1:60 (v/v) (Pw), obtained from a heavy clay soil in the Netherlands. Colloidal particles, which passed a 0.45‐μm filter, caused a large overestimation of MRP. The low ionic strength of the Pw filtrates (on average 0.64 mmolc L−1) probably caused soil dispersion and increased detachment of colloids from soil during extraction. After NaCl addition, followed by 0.45‐μm filtration, MRP was on average 93% lower. This can be ascribed to flocculation of colloids and removal by filtration. A low ionic strength can thus lead to the direct disturbance by colloidal particles of MRP measurement in waters from soils sensitive to release of colloids.
Bilateral congenital diaphragmatic hernia with absent pleura and pericardium
Authors: St. Peter Shawn D. , Shah Sohail R. , Little Danny C. , Calkins Casey M. , Sharp Ronald J. , Ostlie Daniel J. 
Published: July 2005

AbstractBACKGROUNDBilateral congenital diaphragmatic hernia is a rare form of diaphragmatic hernia. Independently, pericardial defects are an extremely rare phenomenon. In the case presented, we provide the first complete description of an infant with bilateral congenital diaphragmatic hernia with complete agenesis of the pericardium and inferior parietal pleura.CASEA male infant was born at 38 weeks of gestation with a prenatal diagnosis of left‐sided congenital diaphragmatic hernia. After 1 week of aggressive management, the patient was taken to the operating room for repair. Intraoperatively, the patient was found to have absence of the diaphragm bilaterally, no pleura inferiorly, and no pericardium. A biological mesh was used to construct a diaphragm. At 6 months of age, the patient is growing normally, requiring only supplemental oxygen without pressure support.CONCLUSIONSEmbryologically, this anomaly represents complete lack of development of the pleurocardial folds, pleuroperitoneal folds, and transverse septum, which is previously unreported. Birth Defects Research (Part A), 2005. © 2005 Wiley‐Liss, Inc.