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sedimentary organic matter supply from the basin’s hinterland on the seawater’s pH conditions has not yet been addressed. Fig. 1 Paleogeography of the Lower Muschelkalk Basin during Pelsonian times (from Götz and Feist

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Abstract  

Oxyreactive Thermal Analysis (OTA) and pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) have been performed on highly matured, uraniferous samples. Organic matter investigated by OTA gives two exothermic peaks on DTA curves. The dominant peak appearing at temperature higher than 500C, confirm the high maturity of the organic matter. Results of analysis by Py-GC-MS complement the OTA results. The organic matter in all of the samples shows the same general pyrolysis characteristics. The pyrograms are dominated by low molecular mass aromatic hydrocarbons. The samples differ in relative abundances of the compounds. The changes in temperature and intensity of the lower-temperature peak in OTA method and differences in relative abundances of aromatic hydrocarbons were used to investigate differences in thermal maturity of the organic matter.

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Cereal Research Communications
Authors: Andrea Huisz, Steven Sleutel, Tibor Tóth, Georges Hofman, Stefaan Neve and Tamás Németh

2004 Cambardella, C. A., Elliott, E. T. (1992). Particulate soil organic matter changes across a grassland cultivation sequence. Soil Sci Soc of Am J

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Smallholders in the tropics add different organic materials to their crops at different times, based on the availability of materials and labour. However, the time of application could have an effect on the establishment and early growth of crops, especially their root systems, which has not yet been clearly identified. This paper presents the results of a study conducted under greenhouse conditions using soils from a field treated with three organic materials at 4 or 2 weeks before or at the planting of maize seeds, corresponding to the times that tropical smallholders apply these materials. The organic materials used were leaves of Gliricidia sepium and Tithonia diversifolia or rice straw, incorporated at a rate equivalent to 6 Mt ha −1 . A control treatment where no organic matter was added was used for comparison. The impact of the treatments on soil properties at the planting of maize seed and detailed root analysis based on root lengths were carried out until the last growth stage (V4). The addition of organic matter improved the soil characteristics, and the impact of adding Gliricidia leaves was most pronounced when incorporated 2 weeks before planting. The benefits of leaves of Tithonia or rice straw on soil quality parameters were clearly evident when added 4 weeks before planting. Organic matter enhanced the root number, root length, root growth rate and branching indices. All the organic materials suppressed the growth of maize roots when applied at planting, suggesting the existence of allelopathic effects, which could result in poor growth. The most benefits in terms of root growth were observed with Tithonia .

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Abstract  

The core samples of oil- and bitumen-containing rocks from Tatarstan's deposits of different ages were studied by thermal analysis methods (DTA, TG, DTG). Based on the obtained data, a procedure was elaborated for determining the enclosed organic matter content and the index of its fraction composition. A significant increase of the organic matter content in the core and its enrichment in high-molecular aromatic structures were shown to occur for the oil-containing rock samples when passing from the Devonian to Carboniferous and Permian deposits. The core samples of the Devonian oil-containing rocks may be divided into three groups: the samples taken from the zones where waste water flooding has been started relatively recently (1), or fresh water flooding has been carried on for a long time (2) and the samples of rock containing clay minerals as impurities. Thus, thermal analysis can be used in geochemical studies to identify the organic matter enclosed by oil- and bitumen-containing rocks.

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Alberts, J. J. & Takács, M., 2004a. Total Luminescence Spectra of IHSS standard and reference fulvic acids, humic acids and natural organic matter: Comparison of aquatic and terrestrial source terms. Organic

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Community Ecology
Authors: C. Calderón del Cid, R. S. Rezende, A. R. Calor, J. S. Dahora, L. N. de Aragão, M. L. Guedes, A. N. Caiafa and A. O. Medeiros

, P. , de Souza Rezende , R. , Feio , M.J. , Leite , G.F.M. , Alvin ‚E. , Quintão , J.M.B. , Araújo , F. and Gonçalves Júnior , J.F. 2017 . Temporal and spatial patterns in inputs and stock of organic matter in savannah

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Introduction Organic matter content is a critical factor of soil quality and an important regulator of CO 2 in the atmosphere. The dry combustion method of measuring soil organic carbon (SOC) concentration dates back to 1900

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Albrecht, A., Rangon, L., Barret, P. (1992): Effets de la matière organique sur la stabilitè structurale et la dètachabilitè ďun vertisol et ďun ferrisol (Martinique). [Effects of organic matter on the structural

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Introduction Current estimates are that 1500–2000 Pg (1 Pg = 10 15 g) of carbon are stored in the top meter of the Earth's soils, making soil organic matter (SOM) the third largest global C pool after the oceanic and geologic

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