bluuebunny/crossref_metadata_2025_split huggingface dataset:
Soil Electrical Conductivity and Water Content Affect Nitrous Oxide and Carbon Dioxide Emissions in Intensively Managed Soils
Authors: Adviento‐Borbe M. A. A. , Doran J. W. , Drijber R. A. , Dobermann A. 
Published: October 2006

ABSTRACTAccumulation of soluble salts resulting from fertilizer N may affect microbial production of N2O and CO2 in soils. This study was conducted to determine the effects of electrical conductivity (EC) and water content on N2O and CO2 production in five soils under intensive cropping. Surface soils from maize fields were washed, repacked and brought to 60% or 90% water‐filled pore space (WFPS). Salt mixtures were added to achieve an initial in situ soil EC of 0.5, 1.0, 1.5 and 2.0 dS m−1 The soil cores were incubated at 25°C for 10 d. Average CO2 production decreased with increasing EC at both soil water contents, indicating a general reduction in microbial respiration with increasing EC. Average cumulative N2O production at 60% WFPS decreased from 2.0 mg N2O‐N m−2 at an initial EC of 0.5 dS m−1 to 0.86 mg N2O‐N m−2 at 2.0 dS m−1 At 90% WFPS, N2O production was 2 to 40 times greater than that at 60% WFPS and maximum N2O losses occurred at the highest EC level of 2.0 dS m−1 Differences in the magnitude of gas emissions at varying WFPS were due to available substrate N and the predominance of nitrification under aerobic conditions (60% WFPS) and denitrification when oxygen was limited (90% WFPS). Differences in gas emissions at varying soil EC may be due to changes in mechanisms of adjustment to salt stress and ion toxicities by microbial communities. Direct effects of EC on microbial respiration and N2O emissions need to be accounted for in ecosystems models for predicting soil greenhouse gas emissions.
Source‐Related Transport of Phosphorus in Surface Runoff
Authors: Shigaki Francirose , Sharpley Andrew , Prochnow Luís Ignácio 
Published: October 2006

ABSTRACTContinual application of mineral fertilizer and manures to meet crop production goals has resulted in the buildup of soil P concentrations in many areas. A rainfall simulation study was conducted to evaluate the effect of the application of P sources differing in water‐soluble P (WSP) concentration on P transport in runoff from two grassed and one no‐till soil (2 m2 plots). Triple superphosphate (TSP)–79% WSP, low‐grade single superphosphate (LGSSP)–50% WSP, North Carolina rock phosphate (NCRP)–0.5% WSP, and swine manure (SM)–30% WSP, were broadcast (100 kg total P ha−1) and simulated rainfall (50 mm h−1 for 30 min of runoff) applied 1, 7, 21, and 42 d after P source application. In the first rainfall event one d after fertilizer application, dissolved reactive P (DRP) and total P (TP) concentrations of runoff increased (P < 0.05) for all soils with an increase of source WSP; with DRP averaging 0.27, 0.50, 14.66, 41.69, and 90.47 mg L−1; and total P averaging 0.34, 0.61, 19.05, 43.10, and 98.06 mg L−1 for the control, NCRP, SM, LGSSP, and TSP, respectively. The loss of P in runoff decreased with time for TSP and SM, such that after 42 d, losses from TSP, SM, and LGSSP did not differ. These results support that P water solubility in P sources may be considered as an indicator of P loss potential.
Impacts of Land Cover on Stream Hydrology in the West Georgia Piedmont, USA
Authors: Schoonover Jon E. , Lockaby B. Graeme , Helms Brian S. 
Published: October 2006

ABSTRACTThe southeastern United States is experiencing rapid urban development. Consequently, Georgia's streams are experiencing hydrologic alterations from extensive development and from other land use activities such as livestock grazing and silviculture. A study was performed to assess stream hydrology within 18 watersheds ranging from 500 to 2500 ha. Study streams were first, second, or third order and hydrology was continuously monitored from 29 July 2003 to 23 September 2004 using InSitu pressure transducers. Rating curves between stream stage (i.e., water depth) and discharge were developed for each stream by correlating biweekly discharge measurements and stage data. Dependent variables were calculated from discharge data and placed into 4 categories: flow frequency (i.e., the number of times a predetermined discharge threshold is exceeded), flow magnitude (i.e., maximum and minimum flows), flow duration (i.e., the amount of time discharge was above or below a predetermined threshold), and flow predictability and flashiness. Fine resolution data (i.e., 15‐min interval) were also compared to daily discharge data to determine if resolution affected how streams were classified hydrologically. Urban watersheds experienced flashy discharges during storm events, whereas pastoral and forested watersheds showed less flashy hydrographs. Also, in comparison to all other flow variables, flow frequency measures were most strongly correlated to land cover. Furthermore, the stream hydrology was explained similarly with both the 15‐min and daily data resolutions.
The Legacy of Leaded Gasoline in Bottom Sediment of Small Rural Reservoirs
Authors: Juracek Kyle E. , Ziegler Andrew C. 
Published: October 2006

ABSTRACTThe historical and ongoing lead (Pb) contamination caused by the 20th‐century use of leaded gasoline was investigated by an analysis of bottom sediment in eight small rural reservoirs in eastern Kansas, USA. For the reservoirs that were completed before or during the period of maximum Pb emissions from vehicles (i.e., the 1940s through the early 1980s) and that had a major highway in the basin, increased Pb concentrations reflected the pattern of historical leaded gasoline use. For at least some of these reservoirs, residual Pb is still being delivered from the basins. There was no evidence of increased Pb deposition for the reservoirs completed after the period of peak Pb emissions and (or) located in relatively remote areas with little or no highway traffic. Results indicated that several factors affected the magnitude and variability of Pb concentrations in reservoir sediment including traffic volume, reservoir age, and basin size. The increased Pb concentrations at four reservoirs exceeded the U.S. Environmental Protection Agency threshold‐effects level (30.2 mg kg−1) and frequently exceeded a consensus‐based threshold‐effects concentration (35.8 mg kg−1) for possible adverse biological effects. For two reservoirs it was estimated that it will take at least 20 to 70 yr for Pb in the newly deposited sediment to return to baseline (pre‐1920s) concentrations (30 mg kg−1) following the phase out of leaded gasoline. The buried sediment with elevated Pb concentrations may pose a future environmental concern if the reservoirs are dredged, the dams are removed, or the dams fail.
Using Simulated Rainfall to Evaluate Field and Indoor Surface Runoff Phosphorus Relationships
Authors: Guidry A. R. , Schindler F. V. , German D. R. , Gelderman R. H. , Gerwing J. R. 
Published: October 2006

ABSTRACTWhile numerous studies have evaluated the efficacy of outdoor rainfall simulations to predict P concentrations in surface runoff, few studies have linked indoor rainfall simulations to P concentrations in surface runoff from agricultural fields. The objective of this study was to evaluate the capacity of indoor rainfall simulation to predict total dissolved P concentrations [TP(<0.45)] in field runoff for four dominant agricultural soils in South Dakota. Surface runoff from 10 residue‐free field plots (2 m wide by 2 m long, 2–3% slope) and packed soil boxes (1 m long by 20 cm wide by 7.5 cm high, 2–3% slope) was compared. Surface runoff was generated via rainfall simulation at an intensity of 65 mm h−1 and was collected for 30 min. Packed boxes produced approximately 24% more runoff (range = 2.8–3.4 cm) than field plots (range = 2.3–2.7 cm) among all soils. No statistical differences in either TP(<0.45) concentration or TP(<0.45) loss was observed in runoff from packed boxes and field plots among soil series (0.17 < P < 0.83). Three of four soils showed significantly more total P lost from packed boxes than field plots. The TP(<0.45) concentration in surface runoff from field plots can be predicted from TP(<0.45) concentration in surface runoff from the packed boxes (0.68 < r2 < 0.94). A single relationship was derived to predict field TP(<0.45) concentration in surface runoff using surface runoff TP(<0.45) concentration from packed boxes. Evidence is provided that indoor runoff can adequately predict TP(<0.45) concentration in field surface runoff for select soils.
Effects of Watershed‐Scale Land Use Change on Stream Nitrate Concentrations
Authors: Schilling Keith E. , Spooner Jean 
Published: October 2006

ABSTRACTThe Walnut Creek Watershed Monitoring Project was conducted from 1995 through 2005 to evaluate the response of stream nitrate concentrations to changing land use patterns in paired 5000‐ha Iowa watersheds. A large portion of the Walnut Creek watershed is being converted from row crop agriculture to native prairie and savanna by the U.S. Fish and Wildlife Service at the Neal Smith National Wildlife Refuge (NSNWR). Before restoration, land use in both Walnut Creek (treatment) and Squaw Creek (control) watersheds consisted of 70% row crops. Between 1990 and 2005, row crop area decreased 25.4% in Walnut Creek due to prairie restoration but increased 9.2% in Squaw Creek due to Conservation Reserve Program (CRP) grassland conversion back to row crop. Nitrate concentrations ranged between <0.5 to 14 mg L−1at the Walnut Creek outlet and 2.1 to 15 mg L−1at the downstream Squaw Creek outlet. Nitrate concentrations decreased 1.2 mg L−1over 10 yr in the Walnut Creek watershed but increased 1.9 mg L−1over 10 yr in Squaw Creek. Changes in nitrate were easier to detect and more pronounced in monitored subbasins, decreasing 1.2 to 3.4 mg L−1in three Walnut Creek subbasins, but increasing up to 8.0 and 11.6 mg L−1in 10 yr in two Squaw Creek subbasins. Converting row crop lands to grass reduced stream nitrate levels over time in Walnut Creek, but stream nitrate rapidly increased in Squaw Creek when CRP grasslands were converted back to row crop. Study results highlight the close association of stream nitrate to land use change and emphasize that grasslands or other perennial vegetation placed in agricultural settings should be part of a long‐term solution to water quality problems.
Chloride Effects on Nitrogen Dynamics in Forested and Suburban Stream Debris Dams
Authors: Hale Rebecca L. , Groffman Peter M. 
Published: October 2006

ABSTRACTOrganic debris dams (accumulations of organic material) can function as “hotspots” of nitrogen (N) processing in streams. Suburban streams are often characterized by high flows that prevent the accumulation of organic debris and by elevated concentrations of solutes, especially nitrate (NO3−) and chloride (Cl−). In this study we (1) studied the effects of urbanization on the extent and characteristics of debris dams in large and small streams and (2) evaluated the effects of NO3−and Cl−on rates of N cycle processes in these debris dams. In some suburban streams debris dams were small and rare, but in others factors that reduce the effects of high stream flows fostered the maintenance of debris dams. Ambient denitrification enzyme activity (DEA) in these suburban and forested streams was positively correlated with stream NO3−concentrations. In laboratory microcosms, DEA in debris dam material from a forested reference stream was increased by NO3−additions. Chloride additions constrained the response of DEA to NO3−additions in material from the forested stream, but had no effect on DEA in material from streams with a history of high Cl−levels. Chloride additions changed the sign of net N mineralization from negative (consumption of inorganic N) to positive in debris dam material from the forested reference stream, but had no effect on net mineralization in material from streams with a history of exposure to Cl−Understanding the factors regulating the maintenance and N cycling activity of organic debris, and incorporating them into urban stream management plans could have important effects on N dynamics in suburban watersheds.
Sulfadimethoxine Degradation Kinetics in Manure as Affected by Initial Concentration, Moisture, and Temperature
Authors: Wang Q.‐Q. , Bradford S. A. , Zheng W. , Yates S. R. 
Published: October 2006

ABSTRACTSulfadimethoxine is a widely used sulfonamide veterinary antibiotic and could be a source of agricultural contamination. Therefore, information is needed about its degradation kinetics in manure under aerobic conditions. Based on the analysis of first‐order kinetics and the assumption that sulfadimethoxine availability for degradation in manure could be limiting, a new kinetic model was developed and was found to fit the degradation kinetics well. The degradation rate in sterile manure was found to be much lower than in nonsterile manure, indicating that biodegradation was significant. In biologically active manure, the degradation rate constant decreased with increasing initial concentration of sulfadimethoxine, implying that the activity of the degrading microorganisms was inhibited. Increasing moisture or temperature was found to increase sulfadimethoxine degradation in manure. Mixing manure containing high levels of sulfadimethoxine with manure containing lower levels may result in more rapid degradation, thus greatly diminishing sulfadimethoxine contamination in manure and significantly reducing sulfadimethoxine inputs into the environment. During treatment, keeping the manure moist and storing in a moderately warm place under aerobic conditions may also help to diminish sulfadimethoxine contamination.
Escherichia coli Loading at or Near Base Flow in a Mixed‐Use Watershed
Authors: Gentry Randall W. , McCarthy John , Layton Alice , McKay Larry D. , Williams Dan , Koirala Shesh R. , Sayler Gary S. 
Published: October 2006

ABSTRACTThis study analyzed the occurrence of Escherichia coli in a mixed land‐use watershed with human, cattle, and wildlife fecal inputs located in a karstic geologic region using synoptic monitoring (samples taken throughout the watershed system) during base‐flow conditions. The objective of the study was to evaluate the occurrence of E. coli during base‐flow conditions for several months at seven different main channel and nine different tributary sampling sites in the Stock Creek watershed, a 49.3‐km2 basin located in Knoxville, TN. Escherichia coli densities were measured using the Colilert (Defined Substrate Technology) method. The instantaneous loads for E. coli were determined from measured flow rates and E. coli densities, with the highest loading rates observed in the late fall. The study indicated a strong correlation between E. coli load rate (colony‐forming units [CFU]/d), 7‐d antecedent precipitation, and turbidity. Water quality data, however, also exhibited a spatial dependency; for example, the E. coli load rate was better correlated with turbidity in the slower draining basin tailwater sampling sites than in the faster draining upstream headwater sampling sites. In the headwater sites, the E. coli load rate was better correlated with 7‐d antecedent precipitation than turbidity.
Mice lacking the p75 receptor fail to acquire a normal complement of taste buds and geniculate ganglion neurons by adulthood
Authors: Krimm Robin F. 
Published: November 2006

AbstractBrain‐derived neurotrophic factor and neurotrophin‐4 are required for normal taste bud development. Although these neurotrophins normally function via the tyrosine kinase receptor, trkB, they also bind to the pan‐neurotrophin receptor, p75. The goal of the present study was to determine whether the p75 receptor is required for the development or maintenance of a full complement of adult taste buds. Mice with p75 null mutations lose 34% of their circumvallate taste buds, 36% of their fungiform papillae, and 26% of their fungiform taste buds by adulthood. The reduction of taste buds in the adult circumvallate papilla was similar to that observed previously at postnatal day 7 (Fan et al. Brain Res Dev Brain Res 2004;150:23–39). Taken together, these findings indicate that the p75 receptor is critical for the development of a full complement of taste buds, but is not required for maintenance of circumvallate taste buds in adulthood. Immunolabeling for p75 was not observed in taste buds, indicating that p75 signaling influences taste bud number indirectly. Geniculate ganglion neurons, which provides innervation to fungiform taste buds, express the p75 receptor. Mice with p75 null mutations also have fewer neurons in the geniculate ganglion. Together, these results suggest that the p75 receptor is important for the survival of geniculate neurons and geniculate neuron survival is required for the development of a full complement of taste buds by adulthood. Anat Rec Part A, 2006. © 2006 Wiley‐Liss, Inc.
Zur prae‐ und postoperativen nutritiven Versorgung von Ratten mit Enterostomata
Authors: Müller‐Beuthow W. , Schulze J. , Grütte F.‐K. 
Published: November 2006

AbstractAn Ratten mit Ileostomata und Colostomata wurde der Ernährungseinfluß während der perioperativen Phase auf Freßverhalten, Darmtätigkeit und Körpermasseentwicklung untersucht. Eine ad libitum‐Fütterung bis unmittelbar vor Operationsbeginn erwies sich als vorteilhaft. Das postoperative Nahrungsregime ist von ausschlaggebender Bedeutung für das Überleben der operierten Tiere. Die beste postoperative Entwicklung wurde im Falle von ileostomierten Ratten mit einer nährstoff‐ und energiereichen, ballaststoffarmen Diät erzielt. Der Operationserfolg bei Ratten mit Colostomata wird durch Obstipationen des vor dem Stoma gelegenen Darmabschnittes, die häufig zum Verschluß führen, beeinträchtigt. Nur mit einer lactosereichen, eiweißarmen Diät konnte eine spontane Chymusentleerung bei diesen Tieren indiziert werden. Je nach Lage der Enterostomata wird eine differenzierte prae‐ und postoperative Ernährung der Versuchstiere empfohlen.
Production and frozen storage of minced Baltic herring (Clupea harengus membras)
Authors: Kiesvaara M. J. , Granroth B. 
Published: November 2006

AbstractThe production and storage of minced Baltic herring was investigated to develop a convenient semi‐finished product which could be manufactured industrially and stored frozen as such or in the form of pre‐manufactured convenience foods. Baltic herring has several disadvantages as a raw material for such use, namely small size, dark colour, strong odour, and soft texture. Dark colouring of the mince can be reduced considerably by skinning. The dark pigments of the belly lining are eliminated on filleting. The strong odour which evolves when Baltic herring is heated can be moderated by adding a small amount of suitable protein such as milk protein. This addition also has a positive influence on the water binding capacity and taste of the mince. The texture is improved by adding barley or wheat starch or possibly by pre‐texturing part of the mince by heating to give a heterogeneous structure. Fish are skinned prior to mincing and 0.1–0.2% ascorbic acid or sodium erythorbate is added as antioxidant. The mince is vacuum packed in a gas‐tight material such as polyethylene/polyamide laminate. In this way it is possible to store frozen minced Baltic herring at −25 °C for at least one year. Even after such a period the mince is still quite acceptable and no rancidity or peroxides can be detected. Although it appears that certain adverse protein changes cannot be avoided during frozen storage, their effects can be masked in part by adding milk protein, starch and triphosphate to increase the water‐binding capacity and generally improve the functional properties of the mince and mince‐based products.
Thermodynamic compatibility of proteins in aqueous media. Part. I. Phase diagrams of some water – protein A – protein B systems
Authors: Polyakov V. I. , Kireyeva O. K. , Grinberg V. Ya. , Tolstoguzov V. B. 
Published: November 2006

AbstractThe thermodynamic compatibility of proteins belonging to different classes according to Osborne has been investigated in aqueous media. Phase equilibrium for water ‐ ovalbumin ‐ soybean globulin fraction, water ‐ ovalbumin ‐ casein, water ‐ casein ‐ gliadin and water ‐ casein ‐ soybean globulin fraction systems has been investigated.The data obtained were analysed according to the theoretical concepts of Scott, Patterson and Prausnitz concerning the effect of polymer molar masses and the solvent quality on the phase equilibrium in similar systems. The analysis performed indicates that these concepts can be applied to the water ‐ protein A ‐ protein B systems.The phase equilibrium in water ‐ protein A ‐ protein B systems has some distinctive features as compared to that in systems containing two synthetic polymers in the single solvent. Firstly, proteins are usually compatible in a broader concentration range as compared to common polymers. Moreover, the separation of water ‐ protein A ‐ protein B systems into two phases often results in a considerable concentration of one of the protein components. Apparently, the latter fact can be associated with the marked difference in the interaction parameter of proteins belonging to different classes with the solvent, and, hence, with the marked difference in the hydrophilicity of the proteins investigated.
Chemical characteristics and physico‐chemical properties of faba bean starch isolated from the by‐product after protein extraction
Authors: Fornal Ł. , Soral‐Śmietana M. , Fornal J. 
Published: November 2006

AbstractStudies were made on the effect of protein extraction from faba bean flour, using water, whey and waste effluents from potato processing on chemical composition of starch and its physico‐chemical properties. The results showed that the chemical composition of starch obtained from the by‐product was different compared to native starch. The range of gelatinization temperature and maximal viscosity at 95 °C were also noticeably changed compared to native starch.
Stand und Perspektiven der Stärkeindustrie der DDR
Authors: Mörle‐Heynisch W. , Schirner R. 
Published: November 2006

AbstractIndustriekartoffeln, Mais und Weizen bilden die ausschließliche Rohstoffgrundlage der Stärkeindustrie der DDR. Gegenwärtig werden 54% der Gesamtstärkeproduktion in einer 2. Veredlungsstufe modifiziert, derivatisiert, hydrolysiert. Prognostiziert wird bis 1990 eine jährliche Steigerung des Stärkebedarfs von 7% sowie die Erhöhung des Anteils von Stärkeveredlungsprodukten auf mehr als 70%Ausgehend von dem erreichten Stand des Entwicklungsniveaus und der Produktion von Erzeugnissen, Produktionsverfahren und Ausrüstungen werden die Aufgaben für die Grundlagen und Vorlaufforschung, Erzeugnis‐ und Verfahrensentwicklung sowie für die Strukturpolitik dargelegt.
Aspekte zur Gewinnung und zum Einsatz von Stärke aus Roggen
Authors: Krätz H. 
Published: November 2006

AbstractEs werden Labor‐Untersuchungen zur Gewinnung von Roggenstärke aus wäßrigen Roggenmehlsuspensionen sowie zur Verwendung der Roggenstärke für die Stärkesirup‐ und Oxystärkeherstellung unter Beachtung produktionstechnischer Aspekte beschrieben. Die zur Gewinnung abgeleiteten verfahrenstechnischen Prinzipien betreffen die Auflösung und Teilhydrolyse kaltwasserlöslicher Roggeninhaltsstoffe, die Klassierung der unlöslichen und die abschließende Auswaschung der gelösten Substanzen bei weitgehender Rückführung von extrakthaltiger Flüssigkeit. Unter Berücksichtigung des Zöliakieproblems beziehen sich die Untersuchungen zum Einsatz der Roggenstärke auf die Säurehydrolyse zu Stärkesirup und vor allem auf die Herstellung und Eigenschaften von Oxystärke und acetylierter Oxystärke. Unter Berücksichtigung bestimmter getreidestärke‐ und artspezifischer Eigenschaften ist Roggenstärke geeignet, in volkswirtschaftlich relevantem Umfang Kartoffelstärke zu ersetzen.