bluuebunny/crossref_metadata_2025_split huggingface dataset:
Water Vapor Adsorption as Related to Liming of Acidic Sandy Forest Soil
Authors: Sokolowska Z. , Józefaciuk G. , Sokolowski S. , Renger M. , Wilczynski W. 
Published: February 2007

AbstractWater vapor adsorption isotherms were measured for soil samples taken from five subsequent 10 cm layers of limed and unlimed Cambic Arenosol under forest. Applying the numerical approximation of adsorption isotherms with an exponential isotherm equation and a local BET model, the surface areas, average adsorption energies and adsorption energies distribution functions were calculated. The values of average adsorption energies increased slightly with the depth of the layer, however no marked differences were observed between the average energies for the equivalent layers of both limed and unlimed profiles. For unlimed profiles the energy distribution functions possessed two maxima, the smaller maximum, however, disappeared in limed profile.
Nitratumverteilung in Böden durch Trocknung
Authors: Deller Berthold 
Published: February 2007

AbstractStechzylinderproben wurden bei 105°C getrocknet, in Schichten unterteilt und deren Nitratgehalt gemessen. An der Ober‐ und Grundfläche stieg die Nitratkonzentration gegenüber dem Probeninneren stark an. Dieser Prozeß dürfte bei der Trocknung von Bohrkernen generell stattfinden und erklärt Homogenisierungsprobleme bei der Untersuchung getrockneter Bodenproben auf Nitrat.
Response of Phosphate Adsorption by Acid Soils to the Use of Electrolyte
Authors: Prodromou Konstantinos P. 
Published: February 2007

AbstractThe presence of electrolyte in the solution, increases the amount of adsorbed anions. This increase, mainly depends on the kind of electrolyte, the concentration in the solution and the pH of treatment.In this work the process of phosphate adsorption in acid soils (Dystric subgroups of Inceptisols and Entisols) with and without use of electrolyte, was studied in order to find the real adsorption capacity of soils and the equations that fit to the adsorption data.It was found out that the shape of the isotherms obtained without electrolyte was different from that with electrolyte. The amount of the adsorbed anions was higher in the later case. The Freundlich equation gave a good fit to the isotherm data and the exponent of Freundlich equation was correlated with some properties of the soils.
Acidification in the Rhizosphere of Rape Seedlings and in Bulk Soil by Nitrification and Ammonium Uptake
Authors: Murányi A. , Seeling B. , Ladewig Erwin , Jungk Albrecht 
Published: February 2007

AbstractAmmonium salts used as fertilizers may cause soil acidification by two different processes: nitrification in soil and net release of protons from roots. Their influence on soil pH may vary depending on the distance from root surface. The aim of this study was to distinguish between these two processes. For this purpose rape seedlings were grown 10 d in a system which separated roots from soil by a fine‐meshed screen. As a function of distance from the plane root layer formed on the screen, pH, titratable and exchangeable acidity and NO3‐ and NH4‐nitrogen were determined. The soil, a luvisol from loess, was supplied with no N or (NH4)2SO4 either with or without a nitrification inhibitor (DCD). The bulk soil pH remained unaffected when no N or 400 mg NH4N kg−1 soil plus DCD was applied but it decreased from 6.6 to 5.8 without DCD. In contrast, rhizosphere pH decreased in all cases, mainly within a distance of 1 mm from the root plane only, but with gradients extending to between 2 and 4 mm into the soil. The strongest pH decrease, from 6.6 to 4.9, occurred at the root surface of plants treated with both NH4‐N and DCD where most of the mineral N remained as ammonium. In this case Al was solubilized in the rhizosphere as indicated by exchangeable acidity. Total soil acidity produced in the NH4 treatment without DCD was mainly derived from nitrification compared to root released protons. However, acidification of the rhizosphere was diminished by nitrification because nitrate ions taken up by the roots counteracted net proton release. It is concluded that nitrification inhibitors may reduce proton input from ammonium fertilizers but enhance acidification at the soil‐root interface which may cause Al toxicity to plants.
Pore size distribution measurements in swell‐shrink soils
Authors: Nagarajarao Y. 
Published: February 2007

AbstractA method for the determination of pore size distribution in swell‐shrink soils was described. Undisturbed core samples, saturated and drained at 1.5 MPa suction, were filled with a non‐polar liquid (xylol), and its retention at suctions lower than 1.5 MPa was measured. Oven dry samples were analyzed in the same way. Derived pore size distributions were compared with those obtained by water desorption.Pore size distributions and their relative changes as a function of water content were related to some soil constituents and properties. Stability factor and sum of montmorillonite and vermiculite significantly influenced the pore size distribution by water release, A higher stability factor resulted in lower relative changes (ratios) in the pore size classes <10 μm and 0.2–10 μm when the samples were drained from saturation to 1.5 MPa suction, however, at extreme dryness, the relative changes were positively correlated to the sum of montmorillonite and vermiculite.
Recent advances in the spectroscopic characterization of soil humic substances and their ecological relevance
Authors: Fründ Rüdiger , Guggenberger Georg , Haider Konrad , Knicker Heike , Kögel‐Knabner Ingrid , Lüdemann Hans‐Dietrich , Luster Jörg , Zech Wolfgang , Spiteller Michael 
Published: February 2007

AbstractNon destructive spectroscopic methods such as 13C‐ and 15N‐NMR provide new insights into the structure of humic substances. Solid state NMR is capable of studying complete native soils by the CPMAS‐technique. By means of nitrogen 15‐enriched composts it is suggested that nitrogen in soil organic matter is mainly located in amide and peptide structures. Most probable assignments are given.The investigation of humification processes in forest soils is possible via an approach which uses several fractionation techniques in combination with degradative and non‐degradative analytical techniques.Besides structure analysis, the 13C‐NMR‐spectroscopy provides important information about the functions of humic substances. By using 13C‐enriched xenobiotics the binding mechanism to organic matter can be elucidated on a molecular basis.Molecular fluorescence spectrometry, a non‐invasive method, is a powerful tool for the quantitative characterization of metal ion complexation by dissolved organic matter in aqueous leaf litter extracts in terms of conditional stability constants and metal binding capacities.
Long‐term impacts of tillage on the soil ecosystem
Authors: Frede Hans‐Georg , Beisecker Richard , Gäth Stefan 
Published: February 2007

AbstractAn overview of the available knowledge of long‐term impacts of different tillage systems on the soil is given. Various studies, carried out in Germany, show that with the transition from conventional (CT) to reduced (RT) and no‐tillage (NT) no reduction in yields is to be expected. Both the concentration and the amount of organic matter in the top soil is increased. However, in the transitional phase nitrogen is accumulated. The biological activity increases as well.The higher compaction has a positive effect on the water holding capacity. On the other hand, the aeration is reduced as well as the thermal conductivity. More stable pore systems cause, on the whole, a higher infiltration capacity and a reduction in erosion. The factors of influence are developed to a different extent, depending on soil texture and climate.
Effects of mustard residues on the carbon and nitrogen turnover in undisturbed soil microcosms
Authors: Hantschel Ralph E. , Priesack Eckart , Hoeve Rolf 
Published: February 2007

AbstractThe C‐ and N‐turnover of undisturbed, irrigated 25 cm soil microcosms of a Typic Agrudalf from loess were followed during a laboratory incubation of about 200 days. Besides the untreated control columns two treatments were installed to test the effects of the application of white mustard (Sinapis alba L.) on both nutrient cycles (either mixing the dried plant residues to 0–8 cm or surface application). Each of the treatments is represented by 4 soil columns to account for soil variability.The C‐budget was mainly altered for soil respiration, which increased for the microcosms treated with mustard rapidly after application. After 4 weeks no differences could be proved however. The loss of soluble C‐compounds, which was unimportant for the budget, reflected no one of the treatments with mustard. Net N mineralization, as calculated from the NO3‐leaching, could be well fitted by zero‐order kinetics. Although the high variability of the net N mineralization of the replicates mustard application significantly rises the N‐release. No difference could be proved for the different techniques of application however. In the mixed treatment 38% of the nitrogen added with the mustard was decomposed during the incubation period, in the surface treatment 34%.
Callose concentration in leaves of field grown Oxalis acetosella (L.) indicates growth impediments
Authors: Wissemeier Alexander H. , Rodenkirchen Hermann 
Published: February 2007

AbstractThe Höglwald, located in Bavaria, is a pure Norway spruce stand, where experimental plots which were limed or not were subjected to normal or acid irrigation (Höglwald Experiment). The growth of the forest herb Oxalis acetosella improved greatly with liming. Callose concentration in leaves of Oxalis reflected the lime effect with about a 2.5 times lower callose concentration in the limed compared to unlimed plots. Acid irrigation increased callose concentration only in the unlimed plot. A negative exponential relationship was established between leaflet area and callose concentration.In a Diagnostic Field Fertilization Experiment in the vicinity of the Höglwald Experiment, Ca and Mg were applied either as carbonate or sulphate and Mn and Si added to experimental plots. In this experiment, it was demonstrated that it was not liming per se, but the application of Ca, that greatly increased the growth of Oxalis. Again, there was a negative correlation between leaflet area and callose concentration in leaves. Chemical analysis of leaves revealed that a Mn concentration > 3.5 mg (g DW)−1 and a Mg concentration > 10 mg (g DW)−1 led to increased callose concentration.
Einfluss von konventioneller und biologisch‐dynamischer Bewirtschaftungsweise auf die mikrobielle Biomasse und deren Stickstoff‐Dynamik in Parabraunerden der Friedberger Wetterau
Authors: v. Lützow Margit , Ottow Johannes C. G. 
Published: February 2007

AbstractDas Ziel der vorliegenden Untersuchungen ist die Erfassung von Fluktuationen der mikrobiellen Biomasse und ihres Stickstoffgehaltes in Abhängigkeit von Bewirtschaftungsmaßnahmen und der Jahreszeit. Versuchsobjekte sind langjährig unterschiedlich intensiv bewirtschaftete Betriebe (biologisch‐dynamisch und konventionell) auf Parabraunerden. Die konventionell bewirtschafteten Felder hatten im Frühjahr (vor Vegetationsbeginn) und im Herbst niedrigere Bio‐C‐, Bio‐N‐Anteile bezogen auf die organische Substanz im Vergleich zu den biologisch‐dynamisch bewirtschafteten Feldern. Während des Aufwuchses der Hauptfrucht vergrößerten sich die Bio‐C‐ und Bio‐N‐Anteile stark, Der Anstieg der Bio‐C‐ und Bio‐N‐Anteile war auf den konventionell bewirtschafteten Feldern höher und kontinuierlich im Vergleich zu den biologisch‐dynamisch bewirtschafteten Schlägen und ist wahrscheinlich sowohl auf eine größere Wurzeldeposition als auch auf die bessere Nährstoffversorgung dieser Felder zurückzuführen. In den biologisch‐dynamisch bewirtschafteten Feldern sank der Bio‐N unter N‐Mangelbedingungen, während der Bio‐C keine Veränderung zeigte. Dadurch weitete sich das C/N‐Verhältnis der mikrobiellen Biomasse, worin die Rolle der mikrobiellen Biomasse sowohl als sink wie auch als source von Nährstoffen deutlich wird. Die durchschnittliche Umsatzzeit des Bio‐N‐Pools betrug auf allen Betrieben ca. 1 Jahr. Die Umsatz/eit des Bio‐C‐Pools war auf den konventionell bewirtschafteten Feldern doppelt so hoch wie auf den biologisch‐dynamisch bewirtschafteten Feldern. Die Ergebnisse weisen auf qualitative und funktionale Unterschiede im Humuskörper sowie auf unterschiedliche interne Nährstoffzyklen hin.
Einfluß unterschiedlicher Gehalte an organischer Bodensubstanz auf das Konsistenzverhalten verschiedener Mineralbodensubstrate
Authors: Kahle Petra , Kretschmer Hermann 
Published: February 2007

AbstractUntersucht wurde der Einfluß des Gehaltes an organischer Substanz auf das Konsistenzverhalten von Böden unterschiedlicher Herkunft und Zusammensetzung. Es ergaben sich statistisch gesicherte Zusammenhänge. Die Plastizitäts‐ und Fließgrenzen wurden in Abhängigkeit von der organischen Substanz substratspezifisch zu höheren Wassergehalten ver‐schoben.
Effect of Various Nitrogen Forms on the pH in Leaf Apoplast and on Iron Chlorosis of Glycine max L.
Authors: Kosegarten H. , Englisch G. 
Published: February 2007

AbstractThe effect of NH4NO3 (control) and increasing NO3‐ levels in nutrient solutions containing no and 100 μM Fe respectively on iron chlorosis of Glycine max was investigated. After two weeks of growth apoplastic pH in excised leaves was measured by means of fluorescence. In plants growing without Fe supply increasing concentrations of NO3‐ in the nutrient solution which also was applied to the cut end of the petiole, resulted in a pH increase in the leaf apoplast from 5.34 (NH4NO3) to 5.50 (NO3‐) associated with chlorosis observed with intact plants. A close negative correlation was found between chlorophyll concentration and pH in the apoplast (r = −0.97). While leaves in the treatment exclusively fed with NO3‐ were strongly chlorotic, those in the NH4NO3 treatment were green. With exception of the plants only fed with NO3‐ the Fe concentration in the leaves was not affected by the type of N nutrition. It is therefore assumed that some Fe is immobilized in the leaf tissue by high apoplast pH induced by an increase in the proportion of nitrate in the nutrient solution.Plants fed with Fe (100 μM) showed no chlorosis, regardless of the form of N nutrition and hence regardless of apoplast pH. The Fe concentration in leaves of Fe fed plants was approximately twice those in the leaves not supplied with Fe.
Einfluß von Mg‐ und Ca‐Mangel auf Mg‐ und Ca‐Gehalte, Chlorophyllgehalt und Chlorophyllfluoreszenz von Fichtennadeln sowie auf die Mikromorphologie und Benetzbarkeit ihrer epicuticulären Wachse
Authors: Schwab Margret , Noga Georg , Barthlott Wilhelm 
Published: February 2007

AbstractIn Gewächshausversuchen wurde der Einfluß eines Mg‐ und/oder Ca‐Mangels in der Nährlösung auf die epicuticulären Wachse der Nadeln von Fichten (Picea abies [L.] Karst.) untersucht. Klonfichten wurden in Quarzsand kultiviert und über Nährlösungen mit Wasser und Nährstoffen versorgt. Pflanzen der Varianten ‐Mg, ‐Ca und ‐Mg/‐Ca erhielten für 2 Vegetationsperioden nur 15 % der entsprechenden Mineralstoffe der Kontrolle.Am Ende der 2. Vegetationsperiode konnte das Vorliegen eines Nährstoffmangels durch den Nachweis erniedrigter Mg‐ und/oder Ca‐Gehalte der Nadeln sowie die Beeinträchtigung der Chlorophyllfluoreszenz dokumentiert werden. Die Mikromorphologie der epicuticulären Wachse sowie die Benetzbarkeit der Nadeloberflächen wurde in keinem der untersuchten Nadeljahrgänge durch den Mangel an Mg und/oder Ca beeinflußt.
Small Scale Heterogeneity of Soil Chemical Properties. II. Fractions of Aluminum and Heavy Metals
Authors: Wilcke Wolfgang , Kaupenjohann Martin 
Published: February 2007

AbstractSoil aggregates from nine horizons of five forest sites in Bavaria were mechanically separated into an aggregate surface fraction and an aggregate core fraction. Seven operationally defined fractions of AI, Cd, Cu, Cr, Ni, Pb, and Zn were determined by a sequential extraction procedure within both aggregate fractions. The CEC, Corg, and oxides of Mn and Fe also were measured. The differences in metal concentrations between surface and core fractions were small but consistent: mainly lithogenic metals (Al, and, within a serpentine derived soil, Ni and Cr) showed lower total concentrations in the surface than in the core fraction. Metals originating primarily from atmospheric deposition form two groups. Cadmium, Pb, and Zn usually showed higher total concentrations in the surface fraction whereas Cu, Cr, and Ni showed no uniform trends. In general, lower proportions of the total metal concentration could be extracted by the residual extraction step (mainly bound within silicates) in the surface than in the core fraction. Accordingly, higher proportions could be extracted by the sum of all other steps (bound to cation exchangers, organic matter, and oxides) in the surface fraction, although in the aggregate surface fraction the concentrations of organic matter and oxides as well as the CEC were lower than in the core fraction. The fact that the sorption capacity of the surface is lower than of the core fraction has to be considered for the identification of external metal inputs. Based on these results, a new method to identify external inputs is proposed.
Einfluß von Sorte und Phosphordüngung auf den Phosphorgehalt und die Aktivität der sauren Phosphatasen von Weizen und Gerste. — Ein Beitrag zur Diagnose der P‐Versorgung von Pflanzen —
Authors: Römer Wilhelm , Beißner Lutz , Schenk Harald , Jungk Albrecht 
Published: February 2007

AbstractEs wird die Frage behandelt, ob die Aktivität der sauren Phosphatasen (Pase) zur Diagnose des P‐Versorgungszustandes besser geeignet ist als der P‐Gehalt der Pflanzen. Hierzu wurde in einem Feldversuch mit gestaffelter P‐Düngung an Winterweizen cv ‘Sperber’ festgestellt, daß die Pase‐Aktivität in den vier untersuchten Entwicklungsstadien eine signifikante Korrelation zum Kornertrag aufwies. Der P‐Gehalt war dagegen nur im ersten Stadium (DC 26–27) signifikant mit dem Kornertrag korreliert.Um die genetische Variabilität des Einflusses der P‐Versorgung auf den P‐Gehalt und die Pase‐Aktivität zu untersuchen, wurden zwei Gefäßversuche mit 9 Winterweizen‐ und 23 Sommergerste‐Sorten bei P‐reicher und P‐armer Anzucht durchgefuhrt. Die Pase‐Aktivität wurde durch die Sortenvariabilität starker beeinflußt als durch die P‐Versorgung. Daraus wird der Schluß gezogen, daß die Pase‐Aktivität als generell anwendbare Maßzahl für die Diagnose der P‐Versorgung ungeeignet ist. Der P‐Gehalt der Pflanzen wird dagegen von der Sorte weniger und von der P‐Versorgung stärker beeinflußt. Er ist daher als geeignetere Kenngröße für die P‐Versorgung von Weizen und Gerste anzusehen. Die Analyse muß im frühen Stadium bis etwa DC 27 vorgenommen werden.
Relations between sulphur supply and glutathione and ascorbate concentrations in Brassica napus
Authors: Schnug Ewald , Haneklaus Silvia , Borchers Anja , Polle Andrea 
Published: February 2007

AbstractUnder conditions of sulphur deficiency sulphur bound in glucosinolates of Brassica species can be remobilized by enzymatic cleavage. The trigger mechanism for the control of the myrosinase activity is supposed to be related to the ascorbate/glutathione cycle (Schnug & Haneklaus, 1993). Studies investigating the influence of the sulphur supply on glucosinolate, glutathione and ascorbate concentrations in vegetative plant tissues reveal a close relationship between sulphur status and glucosinolate resp. glutathione contents whereas such interdependencies are less distinctive for ascorbate.
Glutathion S‐transferases in trees: Inducibility by various organic xenobiotics
Authors: Pflugmacher Stephan , Schroder Peter 
Published: February 2007

AbstractGlutathione (GSH) can be found in plants in considerable amounts. It is very important for numerous metabolic functions and for the detoxification of xenobiotics. The present study was carried out to show the inducibility of glutathione S‐transferase (GST) isozymes in spruce by various substrates commonly used to assay GST activity, Inducers were: chloro‐2,4‐dinitrobenzene (CDNB), 1,2‐dichloro‐4‐nitrobenzene (DCNB), para‐nitrobenzoylchloride (pNBC), fluorodifen and n‐ethylmaleinimide (NEM). Conjugation of CDNB was enhanced by the xenobiotics ranking in the order: CDNB > fluorodifen > pNBC > NEM > DCNB.
Effects of the timing of sulphur application on grain yield and yield components of wheat
Authors: Haneklaus Silvia , Murphy D. P. L. , Nowak G. , Schnug Ewald 
Published: February 2007

AbstractPot experiments were conducted to examine the response of wheat to the timing of sulphur (S) application. Plants were fertilized at different Stages from sowing to the end of flowering. Plants grown without a basal S supply (severe deficiency), which showed deficiency symptoms at ear emergence, required fertilization with S at the tillering stage if yield losses were to be completely avoided. Moderate and slight S deficiency, which did not result in symptoms until after ear emergence, required rectification at the second node stage for full yield to be obtained. Treatment effects on yield were closely associated with effects on the number of kernels per ear. The results show that where S deficiency occurs, fertilization is required before symptoms become evident if yield reductions are to be avoided.
Use of a sulphite containing desulphurization product as sulphur fertilizer
Authors: Mortensen Jørgen , Nielsen Jørgen Dissing 
Published: February 2007

AbstractUse of a sulphite containing desulphurization product (TASP) as a sulphur fertilizer had no negative effects on germination or growth of oilseed rape or white cabbage when applied in an amount corresponding to 48 kg sulphite‐S as calcium sulphite per ha, neither when used alone, nor when mixed with animal slurry. The product increased the plant yield when applied on soils poor in available sulphur.
Uptake of zinc by Brassica napus as affected by sulphur supply
Authors: Helal H. Mohamed , Schnug Ewald , Eickriede Antje , Fild Manfred 
Published: February 2007

AbstractIndustrial crops provide a possibility for utilization of heavy metal polluted soils. Knowledge of the factors which affect metal uptake by crops is therefore essential in order to develop concepts for the management of such soils.In pot experiments the uptake of Zn by oilseed rape increased considerably with the Zn supply. The increase of Zn uptake was counteracted partly by S. This protective effect of S was, however, not related to Zn retention in the roots.
Ermittlung von analytischen Kriterien zur bodentypologischen Einordnung tiefreichend humoser Sandböden im Westmünsterland
Authors: Schöbel Thomas , Wiechmann Horst 
Published: February 2007

AbstractBei Bodenkartierungen im Westmünsterland ergaben sich auf landwirtschaftlich genutzten Flächen Schwierigkeiten bei der systematischen Einordnung von großflächig vorkommenden Sandböden, die über den Pflughorizont hinaus überdurchschnittlich viel Humus aufweisen. Um klären zu können, ob diese mehrere Dezimeter mächtigen, braunen bis graubraunen, tiefhumosen Horizonte auf natürliche Weise oder durch anthropogene Beeinflussung entstanden sind, wurden vergleichende bodenchemische und bodenphysikalische Laboranalysen durchgeführt. Ausgehend von systematisch sicher klassifizierbaren Böden der Kultosole (spez. Plaggenesche; 7 Profile) einerseits und Podsole/Braunerden (8 Profile) andererseits, sollten anhand deren diagnostischer Horizonte signifikant differenzierende Merkmale ermittelt werden, die es ermöglichen, die Horizonte bzw. die Profile mit unklarer Klassifikation (11 Profile) der einen oder anderen sicheren Gruppe zuzuordnen. Bei der statistischen Auswertung der analytischen Laborergebnisse wurden neben univariaten auch multivariate Verfahren der Diskriminanz‐ und Clusteranalyse eingesetzt. Von 11 systematisch fraglichen Bodenprofilen konnten danach 5 als Plaggenesche identifiziert werden. Die anderen wurden, aufgrund des Fehlens besserer systematischer Klassifizierungsmöglichkeiten (z.B. tiefreichend humose Braunerde o.ä.) weiterhin als (Acker‐) Braunerden oder Podsol‐Braunerden bezeichnet.