bluuebunny/crossref_metadata_2025_split huggingface dataset:
Characteristics of organic matter extracted from some solonetzic soils
Authors: Arshad M. A. 
Published: February 2007

Charakterisierung von aus solonetzartigen Böden extrahierter organischer SubstanzIn einer Serie von solonetzartigen und geographisch ähnlichen Böden wurde die Frage der Zusammenhänge zwischen spezifischen Veränderungen in ihrer Zusammensetzung und ablaufenden pedogenen Prozessen untersucht. Im allgemeinen hatten Calciumhumate den höchsten Anteil in allen Profilen, während Huminsäuren, die an Eisen‐ und Aluminiumoxide gebunden waren, den nächsthohen Anteil hatten. Freie Fulvosäuren hatten in den am stärksten verwitterten Horizonten einen höheren Anteil als in jedem anderen untersuchten Horizont. Die C/N‐Verhältnisse verschiedener Humin‐ und Fulvosäure‐Fraktionen waren im Ah‐ viel niedriger als im Bnt‐Horizont.IR‐Untersuchungen von Humin‐ und Fulvosäure‐Fraktionen im Solonetz zeigten Ähnlichkeiten in ihren Strukturen. Jedoch zeigen sich Hinweise auf höheren Aromatisierungs‐ und Polymerisierungsgrad der Huminsäurefraktion.
Molekülkomplexe bei Huminstoffen durch e‐Donator‐ und e‐Acceptor‐Strukturen
Authors: Ziechmann W. 
Published: February 2007

Molecule‐complexes on Humic‐substances by Structures with ϵ‐Donor‐ and ϵ‐Acceptor‐QualitiesFor many considerations with reference to the biosynthesis of humic‐substances it is useful to formulate radicals prevailing for certain phases. Some interesting conclusions can be drawn from this conception based on a great number of experiments.The formation of humic‐substances requires radicable materials, i.e. aromatic substances (initial reactants first order, e.g. lignins). The interpretation of X‐ray diffraction allows to estimate the distributation of aromatic and aliphatic share in humic‐substances.The immense possibilities of chemical reactions therefore form extremely complex materials. But their uniformity makes impossible to separate them exactly.Further, with the formation of particles possessing additional properties of mesomerism the stability of the radicals increases, whilst the humification rate decreases.
Transformations and Transport of NH4+‐N in a Flooded Soil
Authors: Bilal Ibrahim M. 
Published: February 2007

Umbildung und Transport von NH4‐N in einem überfluteten BodenTransport und Transformation von gedüngtem NH4+N wurden in einer überfluteten Bodensäule untersucht, um Aussagen über die Beeinflussung der Wasserqualität durch die Stickstoffdüngung bei Reisböden machen zu können.Am ersten Tag nach der Düngerausbringung erreichte der NH4+‐ Gehalt im Überflutungswasser und in 1,2 cm Bodentiefe (oxidierter Bodenhorizont) Höchstwerte, die mit zunehmender Versuchsdauer bis auf < 1 ppm nach 10 bzw. 16 Tagen abnahmen. In größerer Bodentiefe konnten keine Veränderungen in der NH4+‐Konzentration der Bodenlösung festgestellt werden. Die Gehalte lagen immer unter 1 ppm.Im Überflutungswasser und in der Bodenlösung des oxidierten Oberflächenhorizontes führten Nitrifikationsvorgänge zu Veränderungen der NH4+‐Gehalte. Höchstgehalte an NO2− und NO3− traten etwa 7 bzw. 10 Tage nach der NH4+‐Ausbringung auf. In größerer Bodentiefe konnten Veränderungen in der NO2− und NO3−‐Lösungskonzentration während der Versuchszeit nicht festgestellt werden.Aus den Gehalten an gesamten anorganischem Stickstoff in der Lösungsphase folgt, daß erhöhte N‐Konzentrationen nur im Überflutungswasser und in einer Bodentiefe von 1,2cm auftreten. Die beobachtete Abnahme der N‐Gehalte im Verlauf einer 4‐wöchigen Untersuchungsperiode werden auf Denitrifikations‐, Immobilisierungs‐ und Fixierungsvorgänge zurückgeführt.
Einfluß der N‐Düngung auf den 14C‐Einbau in die Komponenten der äthanollöslichen Fraktion von Sommerweizen verschiedener Entwicklungsstadien
Authors: Höfner W. , Orlovius K. 
Published: February 2007

Influence of N‐fertilization on the 14C‐labelling of the ethanol soluble fraction and its components in spring wheat at different stages of developmentIn spring wheat plants from pot experiments the effect of different N‐fertilization on the 14C‐labelling of the soluble fractions of amino acids, organic acids, and carbohydrates was studied.The fraction of 14C‐labelled compounds, soluble in ethanol, was 50% at the start of the experiment, about 100% during flowering stage and 45% at the end of the experiment.At the end of the 24h 14CO2‐assimilation period 90% of the activity in the plants were water soluble, carbohydrates containing 10 to 20 times higher 14C‐activity than amino or organic acids.In plant labelled with 14CO2 during emergence of the ears, the solubility of 14C‐labelled assimilates decreased till the ripening stage to 15% of the total 14C‐activity, whereas the total activity itself decreased only to 50–80% during the same time.The higher N‐supply results in an enhanced decrease of soluble carbohydrates and in an increase of the soluble amino acid fraction. This leads also to an increased protein synthesis and 14C‐assimilation into the protein of the kernels. The most important plant parts in respect to photosynthesis during the experiment period were upper leaves, upper stems and ears.The 14C‐distribution throughout the plant is mainly determined by the time after 14CO2‐treatment and less by the N‐fertilization. This points to similar pathways of 14CO2‐assimilation in all trials.It is concluded, that the positive effect of the high N‐fertilization on the yield is due to the quick transformation of soluble assimilates into insoluble compounds, e.g. proteins and protein precursors. Increase of yield by high N‐fertilization is also due to a prolonged period of photosynthesis and therefore delayed ripening of the photosynthetic active plant parts.
Symptome von Bormangel und Borüberschuß bei Hibiscus esculentus
Authors: Al‐Badrawy R. , Bussler W. 
Published: February 2007

Boron deficiency and Boron toxicity in Hibiscus esculentusThe development of symptoms in Okra under conditions of B‐deficiency and B‐toxicity was observed. It was compared if the symptoms correspond with the B‐contents and the growth of the plants.Symptoms of Boron deficiency in Okra are the same as in the other annual dicotyledons. The first visible microscopical symptom is a disturbance in the cambium region. Characteristic is an enlargement of the cambium. New divided cells do not differentiate. Visual symptoms are breaking of stems and petioles, thickening of these organs, cracking, dying of the tips and falling of buds. With a periodic supply of Boron correlations between Boron content and deficiency symptoms were not found.In the B‐toxicity range small yellow chlorosis developed on the margins of the older leaves. These symptoms are not to be used for diagnosis. Boron contents higher than 72 μg B/g DM gave a better measure for B‐toxicity. Growth and development of symptoms were in agreement with the high Boron contents.
Wirkung hoher Phosphatdüngung auf die Wachstumsrate, den Zinkgehalt und das P/Zn‐Verhältnis in Weinreben (Vitis vinifera)
Authors: Schropp A. , Marschner H. 
Published: February 2007

Effect of high phosphate fertilization on growth rate, zinc content and P/Zn ratio in grapevines (Vitis vinifera)In a 2 years' pot experiment with a soil low in available Zn, high doses of phosphate fertilizer induced Zn deficiency in grapevines (var. „Riesling”︁ on 5 C root stock). This negative effect of phosphate fertilization could almost be prevented by simultaneous application of Zn to the soil.The negative effect of high phosphate fertilization on the Zn status of the soil was well reflected in both the content of available Zn as well as in the diffusion rate of Zn (65Zn) in the soil.In young leaves of grapevines, Zn deficiency can be expected at Zn contents lower than 20 μg/g DM and P/Zn ratios larger than 170. These values, however, cannot be generalized as external factors modify them considerably. This latter holds true for the P/Zn ratio in particular.The most obvious Zn deficiency symptom was restricted elongation of the shoot due to shorter internodes. Typical for severe Zn deficiency were smaller leaves with intervenal chlorosis or even necrosis and the disappearance of the normally deeply lobed shape of the leaf blade. As a result of the growth inhibition of the shoot apex, growth of axillary buds had been enhanced and this led to a bushy shape of the Zn‐deficient plants.
Fluoreszenzspektroskopische Untersuchungen an Huminsäuren
Authors: Müller‐Wegener U. 
Published: February 2007

Fluorescence Spectroscopic Studies on Humic AcidsThe procedures of the fluorescence spectra of three humic acids have been investigated and compared. Differences were found in three points:
To get the maximum of fluorescence emission, different concentrations of the three humic acids were necessary.
The humic substances differed in pH‐dependence of the fluorescence.
With nearly equal wavelength of fluorescence emission, distinct deviations of the exciting wavelength were pointed out.

The results show a connection between the conditions of the fluorescence and the contents of phenolic hydroxyl groups of the selected humic acids.The measurement of fluorescence is a relatively simple method for the characterization of humic acids.
Geometrische Interpolation von Saugspannungsverteilungen
Authors: Flühler H. , Richard F. 
Published: February 2007

A procedure for interpolating the depth distribution of soil moisture tensionA programmable procedure is described to compute hydraulic gradients from soil moisture tensions non‐linearly distributed with depth.This interpolation‐technique is based upon a geometrical procedure. Compared with other curve smoothing techniques it is flexible with respect to the given data constellation and requires a relatively small computational effort.This method is compared with that of cubic splines.
The effect of sulphur on the yield and chemical composition of raya (indian mustard) (Brassica juncea Coss.) grown on a sulphur deficient soil
Authors: Singh Narendra , Singh Mahendra 
Published: February 2007

Wirkung von Schwefel auf Ertrag und chemische Zusammensetzung von Raya (Brassica juncea Coss.) auf einem Boden mit SchwefelmangelIn einem Gefäßversuch mit Sandboden wurde der Einfluß von Schwefeldüngung (als K2SO4) auf Ertrag und Mineralstoffgehalt von Raya, Sorte R.L. 18, untersucht. Die Schwefeldüngung erfolgte in Höhe von 0; 15; 30; 60; 90 und 120 ppm. Schwefelgaben bis zu 90.
Einfluß von Bewässerung und Plazierung von markierten Stickstoff‐Düngern auf Ertrag und Stickstoffentzug bei Weizen unter semiariden Klimabedingungen im Iran
Authors: Dianati M. 
Published: February 2007

Effect of Irrigation and Fertilizer Placement on the N‐Uptake by Wheat under Semiarid Conditions of Karadj/IranField and greenhouse experiments were conducted under semiarid conditions of Karadj/Iran on a sandy to silty loam of alluvial soils (pH% 8,2) to study the effects of soil moisture regimes and N‐fertilizer placement on yield, N‐uptake and recovery of fertilizer N from 15NH4 15NO3, (15NH2)2CO and (15NH4)2SO4. There were two moisture regimes as main plots (W1 = Irrigation at 50% and W2 = Irrigation at 25% available water in 0–30 cm depth of soil), and two methods of fertilizer placement (broadcast and band application).Irrigation at (W1) increased the grain and straw yield 11 and 19% but not total N‐uptake in the field experiment. (W1)‐irrigation combined with band application resulted in the highest yield and total N‐uptake. Utilization of applied N, however, was higher with (W2)‐irrigation in both fertilizer placements. This result was confirmed by the data of the greenhouse experiment. Band application was superior to broadcast application for fertilizer N‐uptake with both water managements. Ammonium sulfate showed the highest and urea the lowest difference between the two fertilizer placements.
Adsorption und Desorption von Methabenzthiazuron in verschiedenen Böden
Authors: Kerpen W. , Schleser G. 
Published: February 2007

Adsorption and desorption of methabenzthiazuron in various soilsA method investigating adsorption and desorption of pesticides using radioactive tracers and a computer programme is described. The adsorption and desorption of the herbicidal substance methabenzthiazuron in 7 soil samples is investigated.The adsorption of methabenzthiazuron decreases from the Ap‐ to the C‐horizons. A good correlation exists between the adsorbed amount of the herbicidal substance and the C‐ and N‐content of the soils.The relatively highest desorption was found with nearly humusfree soils. The amount of adsorbed herbicide residues, not desorbable by water in 5 desorption cycles, is much higher in the humic soils than in the nearly humusfree soils.From the relationship found between adsorption and corresponding herbicide concentrations proper adsorption values can be predicted for any herbicide concentration within the investigated concentration range by using one single adsorption measurement as a basis of calculation.
Nitrogen mineralization in sandy salt marsh soils of the Netherlands
Authors: Rozema J. , Nelissen H. J. M. , van Der Kroft M. , Ernst W. H. O. 
Published: February 2007

Stickstoffmineralisation in sandigen, salzhaltigen Marschböden der NiederlandeDie jahreszeitlichen Veränderungen der Ammonifikation und Nitrifikation einer alkalischen Salzmarsch wurden untersucht. Ammoniumstickstoff war nicht vorhanden. Bedingt durch den geringen Gehalt an organischem Material bleiben die Nitratgehalte ebenfalls niedrig. Die jahreszeitlichen Schwankungen der aktuellen und der durch Inkubation erhaltenen Nitratmengen werden teilweise durch den Temperaturverlauf verursacht; doch dürften andere Faktoren ebenfalls eine Rolle spielen, wenn auch die nitrifizierenden Bakterien an mittlere Salzgehalte angepaßt sind. Insgesamt gesehen wird die Vegetationsentwicklung der sandigen Salzmarsch durch das geringe Stickstoffangebot nicht gefördert, und die Vegetationszonierung ist unabhängig vom Stickstoffhaushalt.
Vergleich verschiedener Extraktionsmethoden zur Bestimmung der Kaliumverfügbarkeit in Böden
Authors: Schachtschabel P. , Köster W. 
Published: February 2007

Comparison of different methods for the determination of the potassium availability of soilsExtractable K was determined in 148 soil samples by using three different lactate solutions (AL, DL, CAL), 0.1 m HCl and 0.0125 m CaCl2 as extracting agents.The extractable portion of the total exchangeable K (K(NH4)) was found to decrease with increasing content of the < 6,3 μm particle size fraction in the samples.Correlation coefficients were calculated for characterizing the relationship between extracted amounts of K (K values) and the „K numbers”︁. The latter serve as a basis for fertilizer recommendations in the Netherlands, where they have been checked in a great number of field trials. The K number depicts the K supplying power of soils as determined by HCl soluble K, content of the < 16 μm size fraction, and pH.The K (CaCl2) values were found to correlate more closely with the K numbers than the amounts of K extracted with lactate solutions. This is because the influence of particle size on K(CaCl2) is eliminated as shown by multiple regression analysis.The strength of bonding of the easily exchangeable K is reflected much better by the K(CaCl2) values than by the lactate values. Improvement of K fertilizer recommendations by taking K(CaCl2) data as a basis can thus be expected.The different methods of recommendation for K fertilization in the Fed. Republic of Germany and in the Netherlands are illustrated for the soils derived from loess.
Manganese availability as affected by calcium carbonate levels
Authors: Osman A. Z. , El‐Sherif A. F. , Bassiouny H. 
Published: February 2007

Einfluß von Calciumcarbonat auf die Verfügbarkeit von ManganDie vorliegende Arbeit beschreibt Untersuchungen über den Einfluß von CaCO3 auf die Verfügbarkeit von gedüngtem (MnSO4 bzw. MnEDTA, markiert mit 54Mn) und nativem Boden‐Mn. Als Versuchspflanze diente Raygras.Durch CaCO3‐Zusatz zum Boden nimmt die Verfügbarkeit von Mn ab, und zwar sowohl vom Dünger als auch von nativem Boden‐Mn. In jedem Fall war aber natives Boden‐Mn die Hauptquelle von Mn für die Pflanzen, über 90% des Mn in den Pflanzen stammten aus dem nativen Boden‐Mn. Von den beiden Mn‐Düngerformen war die Mn‐Aufnahme aus MnEDTA deutlich besser als aus MnSO4; die Anwendung von Mn‐Chelaten auf stark kalkhaltigen Böden kann daher von Nutzen sein.
Ermittlung von Kennwerten optimaler Magnesium‐Versorgung für Hafer, Sommerweizen und Mais
Authors: Wichmann W. , Finck A. 
Published: February 2007

Determination of plant analysis criteria characterizing the magnesium nutrition of oats, spring wheat and maizeCereal plants from pot trials were analyzed for criteria of optimal Mg nutrition. The critical Mg concentration in dry matter of aerial parts from oats and spring wheat at the beginning of the shooting stage was found to be 1.8 and 1.3 per mille Mg respectively. The critical Mg concentration with maize is about 2,2 per mille in dry matter of yount leaves at tasseling stage.Because the Mg content of oats (based on dry matter) decreases significantly during the shooting stage, it seems advisable to have additional data (Mg content of green matter, Mg/N ratio, Mg/Ca ratio) which are less influenced by plant age.The Mg/Ca ratio appears to be well suited for evaluating the nutritional status of cereals. Minimum critical Mg/Ca ratios (based on per mille contents) are 0,23 for spring wheat, 0.3 for oats and 0.4 for maize.
Die Wirkung der Schwermetalle Chrom, Nickel, Kupfer, Zink, Cadmium, Quecksilber und Blei auf die Aufnahme und Verlagerung von Kalium und Phosphat bei jungen Gerstenpflanzen
Authors: Oberländer Hans‐Erich , Roth Klaus 
Published: February 2007

Effect of the heavy metals chromium, nickel, copper, zinc, cadmium, mercury and lead on uptake and translocation of K and P by young barley plantsThe uptake of potassium and phosphate into the roots and shoots of 7 days old barley plants from double‐labelled (42K, 32P) nutrient solutions containing chromium, nickel, copper, zinc, cadmium, mercury or lead (10−6 ‐ 10−4 moles/1) was measured in a constant environment after 5 hours, in order to compare early stages of toxicity.K and P uptake and translocation were inhibited by the 7 heavy metals to a different extent; K was more affected than P, and translocation of both nutrients into the shoots was more inhibited than uptake into the roots. Plants showed no visible injuries.Mercury had by far the greatest effect, zinc was almost ineffective: K uptake e.g. was reduced to 21% of the control by 10−4 moles Hg/l, but only to 97% by the same amount of Zn, and P translocation was reduced to 8% by Hg, but was not affected by Zn. The least significant effect of Hg was detectable at a concentration of 4.10−7 moles Hg/l ( = 0,08 ppm) in the nutrient solution, the effect of Zn only above 10−4 moles Zn/l ( = 6,5 ppm).Arranging the tested heavy metals according to their effects leads to the sequenceHg > Pb > Cu > Cd > Cr > Ni > Zn which corresponds – apart from two deviations – to the electrochemical series of the elements.
Röntgenfluoreszenzspektrometrische Bestimmung von Spurenelementen in verdünnten wäßrigen Lösungen nach Anreicherung auf Cellulose‐Ionenaustauschern
Authors: Rabe R. 
Published: February 2007

Determination of trace elements in dilute aqueous solutions by X‐ray fluorescence spectrometry after preconcentration on cellulose ion exchangersDifferent methods dealing with the X‐ray fluorescence analysis of solutions are reviewed. Cellulose ion exchangers were found to be a medium for the preconcentration of traces of elements in aqueous solutions. The enrichment is carried out by filtering 11 water containing μg‐amounts of different ions through a column. After drying, the cellulose ion exchangers are pressed into pellets and analysed by X‐ray fluorescence.For the collection step strong acid SE‐ (sulfoethyl‐) cellulose and strong basic DEAE‐(diethylaminoethyl‐) cellulose are used having an exchange capacity of 0,2 meq./gram and 0.85 meq./gram, respectively. The accuray of the method is about ± 10%. Detection limits (theoretical values) are in the range of 1–5 μg.Variations of the method referring to preparation of pellets, sensitivity and column dimensions are discussed.
Abbau von Monolinuron in verschiedenen Böden
Authors: Süß A. , Eben C. 
Published: February 2007

Degradation of monolinuron in different soil typesThe degradation of 14C‐methyl, ‐ureido‐ and ‐phenyl‐labelled monolinuron was studied in laboratory experiments with different soil types. Mineralization of the ureido‐group was followed by two methods. It was found, that the mineralization rate depends on the soil. For the herbicide monolinuron there was a definite degradation characteristic. The release of 14CO2 from the methyl‐ and ureido‐group was faster than from the phenylring. In soil extracts monolinuron was found together with one or two radioactive substances not yet identified. Soil respiration was unchanged after the application of monolinuron. In a sterile soil no degradation occurred.
Überprüfung des Kontaminationsrisikos durch polycyclische aromatische Kohlenwasserstoffe im Erntegut von Möhren und Pilzen bei Anwendung von Müllkompost
Authors: Linne C. , Martens R. 
Published: February 2007

Examination of the risk of contamination by polycyclic aromatic hydrocarbons in the harvested crops of carrots and fungi after the application of composted municipal wasteInvestigations were conducted to determine if the often high, naturally‐occuring concentrations of polycyclic aromatic hydrocarbon (PAHs) present in municipal waste composts could cause hazardous contamination of plants when the composts are used as soil conditioners in agriculture and gardening. Carrots (Daucus carota) and mushrooms (Agaricus bisporus), used as representatives of higher and lower plants, respectively, were cultivated on compost‐free or compost‐amended substrates. To determine concentrations of PAHs in soils and plants a gas‐chromatographic method was employed which allowed benzo(a)pyrene and 12 other PAHs to be determined singly or as isomeric mixtures.In the experiments with Agaricus it was found that fruiting bodies, even though grown in a substrate with very high concentrations of PAHs (i‐ e., 1000 ppb benzo(a)pyrene), contained no detectible quantities of these compounds. In contrast to this, experiments with carrots showed that there was a direct correlation between PAH concentrations in the substrate and PAH concentrations in both below‐ and above‐ground portions of the plants. The 25 to 40 fold increase of the PAH concentration in the substrate containing waste compost caused an increase of these compounds in the carrot roots by the same factor. The only 2 to 4 fold increment of the PAHs in the corresponding foliage was thought to be mainly due to a relatively great portion of air contamination by which the increase of the PAH quantities entering from below ground to the foliage was not so evident.The concentrations of benzo(a)pyrene used in the present series of experiments with composted waste are 7 to 10 times higher than those found in soil to which compost has been added as in practical agricultural application. Relating the result of the described experiments to actual practice, it could be suggested that the normally very low concentrations of PAHs in below ground plant parts would increase with the use of composted municipal waste, but they would not become greater than the concentrations in above ground plant as caused by contamination from naturally occuring PAHs in the air.