Elemental and Molecular Composition of Humic Acids Isolated from Soils of Tallgrass Temperate Rainforests (Chernevaya taiga) by 1H-13C HECTCOR NMR Spectroscopy

The soils of Chernevaya taiga (tallgrass fir-aspen hemiboreal rainforest) have high fertility in comparison with oligotrophic analogs formed in boreal taiga. We have studied humic acids isolated from the soils of Chernevaya and oligotrophic taiga in the Novosibirsk, Tomsk, Kemerovo and the Altai regions of Russia and for the first time the structural and molecular composition of humic acids was determined using 13C CP/MAS and 1H-13C HETCOR NMR spectroscopy. According to data obtained in this study, up to 48% of aromatic compounds accumulate in the soils of Chernevaya taiga, which is higher than in the oligotrophic taiga and comparable with this rate of steppe Chernozems. In the course of active processes of transformation of organic matter, a significant number of aromatic fragments accumulates in the middle horizons of soil profiles. Using 13C CP/MAS spectroscopy, it was possible to identify the main structural fragments (aliphatic and aromatic) that formed in humic acids of the Chernevaya taiga. The HETCOR experiment made it possible to accurately determine the boundaries of chemical shifts of the main groups of structural fragments of humic acids. Our results demonstrate that the stabilization of organic compounds occurs in the soil of the Chernevaya taiga, which leads to the resistance of organic matter to biodegradation that is not typical for benchmark soils of boreal environments.

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Transformation in the Microbial Community and of Organic Substrate During Aerobic Fermentation of Manure

Ecology and Industry of Russia ◽

10.18412/1816-0395-2020-8-22-27 ◽

2020 ◽

Vol 24 (8) ◽

pp. 22-27

Author(s):

I.A. Arkhipchenko ◽

L.G. Bakina ◽

A.Yu. Bruhanov ◽

O.V. Orlova ◽

S.I. Tarasov

Keyword(s):

Organic Matter ◽

Microbial Community ◽

Humic Acids ◽

Organic Substrate ◽

Industrial Complex ◽

Aerobic Fermentation ◽

Wide Range ◽

Mineralization Of Organic Matter ◽

Active Processes ◽

Transformation Of Organic Matter

The results of a study of microbiological processes in controlled aerobic fermentation of litter dung was carried out. It was shown that the introduction of a microbial inoculum into the fermentable substrate allows to obtain an effective biofertilizer. It was found that in the process of transformation of organic matter a specific bacterial complex is formed, which significantly differs in quality composition from the microflora of the litter dung. The change in the composition of the microbial community affected the processes of humification and led to an increase in the proportion of humic acids by more than 3 times in comparison with initial substrate. Thus, along with the active processes of mineralization of organic matter, humification processes occur simultaneously, which is manifested in the formation and accumulation of humic acids. This allows us to justify the feasibility of the developed technology not only for the agro-industrial complex, but also for the microbiological processing of a wide range of organic waste into effective biofertilizers.

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27Al-MAS-NMR-Untersuchungen des thermischen Abbaus von NH4Al(SO4)2·12H2O / 27Al-MAS-NMR Studies on the Thermolysis of NH4Al(SO4)2· 12H2O

Zeitschrift für Naturforschung B ◽

10.1515/znb-1991-1110 ◽

1991 ◽

Vol 46 (11) ◽

pp. 1515-1518 ◽

Cited By ~ 2

Author(s):

Gerhard Wegner ◽

Gert Blumenthal ◽

Dirk Müller ◽

Dirk-Henning Menz ◽

Antje Schmalstieg

Keyword(s):

Nmr Spectroscopy ◽

Structural Changes ◽

Chemical Shifts ◽

Mas Nmr ◽

Nmr Studies ◽

High Stage ◽

27Al Mas Nmr ◽

High Resolution Nmr ◽

First Time

Products of the thermolysis of NH4Al-alum were prepared under dried air and characterized by X-ray powder diffraction, thermogravimetry, and for the first time by solid-state 27Al-MAS-NMR spectroscopy. It was found, that high resolution NMR spectroscopy is applicable to follow up the thermal decomposition and to indicate even minor structural changes. 27Al-MAS-NMR spectra show peaks with characteristic chemical shifts for octahedral Al-units up to a high stage of thermolysis. During the decomposition of Al2(SO4)3 to γ-Al2O3 we again observed three-peak spectra with the specific signal at ≈ 35 ppm for penta-coordinated Al ions as recently proved for the thermolysis of AlCl3 · 6 H2O.

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Stabilization of organic carbon isolated from cryoconite holes in polar and mountain systems by 13С NMR spectroscopy

10.5194/egusphere-egu21-4156 ◽

2021 ◽

Author(s):

Vjacheslav Polyakov ◽

Evgeny Abakumov

Keyword(s):

Carbon Dioxide ◽

Organic Matter ◽

Nmr Spectroscopy ◽

Humic Acids ◽

Carbon Dioxide Emissions ◽

Heterogeneous Systems ◽

Basic Research ◽

13C Nmr Spectroscopy ◽

The Arctic ◽

Additional Contribution

Black carbon is one of the short-lived climatically significant factors. This term refers to climate-forming substances that are located for a short amount of time in the atmosphere - from several days to several years. To identify the role of cryoconite in the conditions of a possible climatic crisis, the stabilization of organic matter isolated from cryoconite holes was assessed. Humic acids are part of the organic matter accumulating in soils and cryoconites and are heterogeneous systems of high-molecular condensed compounds formed as a result of the decomposition of organic remains of plants and animals in terrestrial and aquatic ecosystems. Climatic parameters, precursors of humification, and the local position in the landscape determine the diversity of the composition and properties of HAs. Stabilization of organic material is defined as the transformation of organic matter into a state inaccessible to soil microorganisms, and the very property of stabilization is a characteristic stage in the dynamics of carbon. Using 13C NMR spectroscopy, we determined the proportion of aromatic and aliphatic compounds in the composition of HAs in order to assess the stabilization of organic matter in cryoconites from Mount Elbrus (Caucasus Mountains, Russia), the Arctic (Severnaya Zemlya archipelago, Russia) and Antarctica (King George Island, West Antarctica).Samples for qualitative analysis of carbon accumulated in cryoconites were carried out during fieldwork in 2020. The studied samples were analyzed at the Department of Applied Ecology, St. Petersburg State University. Humic acids (HAs) were extracted from each sample according to a published IHSS protocol. Solid-state CP/MAS 13C-NMR spectra of HAs were measured with a Bruker Avance 500 NMR spectrometer.Thus, it follows from the obtained results that aliphatic fragments of humic acids predominate in all studied cryoconites. A similar composition of humic acids testifies to a single mechanism of accumulation and development of organic matter in glacier regions. Low biological activity and climatic features prevent condensation of high-molecular compounds in the organic matter of cryoconite holes. This is an essential prerequisite for high rates of carbon dioxide emissions into the atmosphere under the conditions of deglaciation of the studied regions. With the thawing of glaciers and the ingress of cryoconites into warmer conditions, an additional contribution of carbon dioxide to the atmosphere can occur and, therefore, increase the possible climate crisis on our planet.This study was supported by Russian Foundation for Basic Research No. 19-05-50107.

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Neue Untersuchung über Inhaltsstoffe der Kreuzdornrinde, IV [1] Die Hauptanthraglykoside der Rinde von Rhamnus catharticus L.: Emodin-8-O-β-gentiobiosid, -glukosid und -primverosid / A New Investigation on the Com position of Rhamni cathartici Cortex, IV [1] The Main Anthraglycosides of the Stem Bark of Rhamnus catharticus L.: Emodin-8-0-/β-gentiobioside, -glucoside and -primveroside

Zeitschrift für Naturforschung C ◽

10.1515/znc-1983-3-403 ◽

1983 ◽

Vol 38 (3-4) ◽

pp. 170-178 ◽

Cited By ~ 6

Author(s):

Hans-W. Rauwald

Keyword(s):

Nmr Spectroscopy ◽

Plant Material ◽

Chemical Shifts ◽

Stem Bark ◽

New Method ◽

Countercurrent Chromatography ◽

Anthraquinone Glycosides ◽

Anthraquinone Derivatives ◽

First Time ◽

C Nmr

From the stem bark of Rhamnus catharticus L. (purging buckthorn) the three main anthraquinone glycosides have been isolated by the new method of droplet-countercurrent-chromatography. Their structures were spectroscopically identified as em odin-8-O-β-gentiobioside, -glucoside and -primveroside. From these the primveroside is a new substance, the gentiobioside has been found for the second time in plant material. The structures were confirmed by 13C NMR spectroscopy for the first time in O-glycosides of emodin type. Especially the differences in 13C chemical shifts of the free resp. acetylated aglycones and glycosides are useful parameters for determining the position of O-glycosylation in the 1,8-dihydroxy-anthraquinone derivatives

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Molecular composition of black carbon in the cryoconite in Arctic by Two-Dimensional 1H-13C HETCOR and 13C CP/MAS

10.5194/egusphere-egu2020-3920 ◽

2020 ◽

Author(s):

Evgeny Abakumov ◽

Viacheslav Polyakov

Keyword(s):

Organic Matter ◽

Nmr Spectroscopy ◽

Black Carbon ◽

Mas Nmr ◽

Molecular Composition ◽

Resonance Spectroscopy ◽

Initial Surface ◽

Current Time ◽

Organic Matter Stabilization ◽

Cp Mas Nmr

Air pollution caused by human activities contributes to the deglaciations of Arctic ice and highland areas, accelerates the process of climate change on the planet and leads to land degradation. Black carbon is the second largest artificial contributor to global warming and accelerates the deglaciations rates after carbon dioxide. Black carbon is formed as a result of incomplete combustion of fossil fuels, biomass, etc. Another important aspect of organic matter role is the presence of specific formations of combined biogenic-mineral materials on the surface of the glaciers &#8211; cryoconites. Cryoconites represent soil like bodies formed not on normal parent material, but on the surface of the ice. This type of accumulations appear in microdepressions, formed due to thawing of ice under accumulation of black carbon on the surface of ice. During the thawing, the cryoconite substances become located deeper in relation to initial surface and this result in additional accumulation of organic matter in microdepressions, they become wider and deeper. Spatial web of cryoconite became more developed and this result in degradation of the glacier surface. This cryoconite formation result in degradation of upper layers of ice and increases deglaciation rates. &#160;The organic carbon of the cryoconite origin could be considered as specific form of natural organic matter stabilization and should be investigated on the molecular level. The advantage nuclear magnetic resonance spectroscopy method is the ability to quantify the content of groups of structural fragments and identify individual structural fragments in humic acid molecules. Studies on the organic compounds of HAs for the soils of the polar area by the 1H-13C (HETCOR) NMR spectroscopy have not been carried out to current time. The advantage of this method is that, when analyzing the spectra of HAs, we can observe cross-peaks of H-C bonds, while for the 13C (CP/MAS) NMR spectroscopy we can only observe chemically bound carbon. The HETCOR method allows the study of single HAs fragments. Thus, the combination of the two methods 1H-13C (HETCOR) and 13C (CP/MAS) NMR spectroscopy can reliably determine the molecular structure of HAs. In our research we investigate the cryoconitte on the Gr&#248;nfjorden area in western Spitsbergen, Svalbard. Analysis of the molecular composition of HAs showed that the molecules of HAs formed on cryoconites are enriched with aromatic fragments and they contain in their composition a considerable number of aromatic fragments (41&#8211;43%) with a relatively small fraction of carbohydrate periphery, as evidenced by higher values of AR/AL (0.75 and 0.69). Higher aromaticity of HAs causes their high stability and the degree of hydrophobicity of HAs in these soils is also higher, which indicates the stabilization of HAs.Acknowledgements: This work was partially supported by Russian Foundation for Basic Research, projects No: 19-54-18003, 19-54-18003 and 19-05-50107

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Characterisation of humic acids, isolated from selected sub-antarctic soils by 13C-NMR spectroscopy

Czech Polar Reports ◽

10.5817/cpr2017-1-1 ◽

2017 ◽

Vol 7 (1) ◽

pp. 1-10 ◽

Cited By ~ 5

Author(s):

Evgeny Abakumov

Keyword(s):

Organic Matter ◽

Nmr Spectroscopy ◽

Humic Acids ◽

13C Nmr ◽

13C Nmr Spectroscopy ◽

Fildes Peninsula ◽

Antarctic Soils ◽

West Antarctic ◽

The Antarctic

Soils of Antarctic considered as underestimated in terms of soils organic matter polls, organic remnants humification/mineralization rates and biogenic-abiogenic interactions. Humic acids of selected Sub Antarctic soils were investigated in terms of elemental and structural composition with special reference to evaluation of organic matter stabilisation degree and assessment of carbon species distributions in the molecules with use of solid state 13C-NMR spectroscopy. It was shown, that the prevailing of aliphatic compounds on the aromatic one is more pronounced in Antarctic soils than in Arctic ones. Average portion of the aromatic compounds is about 20% in humic acids, extracted from soils with evident ornitogenic effect from Fildes Peninsula (Norh-West Antarctic peninsula). This indicates that the role of humification precursors composition is the leading in the humification process. The stabilisation rate of the Antarctic HAs can be assessed as low and the potential risk of biodegradation of their molecules are high.

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Biogenic elements and organic matter production in the ecosystem of Lake Arey, Transbaikal region, Russia

IOP Conference Series Earth and Environmental Science ◽

10.1088/1755-1315/908/1/012041 ◽

2021 ◽

Vol 908 (1) ◽

pp. 012041

Author(s):

G Ts Tsybekmitova ◽

M O Morozova

Keyword(s):

Organic Matter ◽

Water Body ◽

Oxygen Demand ◽

High Water ◽

Inorganic Phosphorus ◽

Biogenic Elements ◽

Conservation Area ◽

Factors Affecting ◽

Active Processes ◽

Transformation Of Organic Matter

Abstract Maintaining an ecological balance of Lake Arey is crucial in terms of nature conservation. Lake Arey is located in Eastern Siberia and is a central object of a designated conservation area of regional significance. The lake is used for recreation (organized and unorganized tourism, sport fishing, mud collection for balneological purposes) not only by residents but also by holidaymakers from other regions. In terms of mineralization level, Lake Arey is a freshwater body. Significant factors affecting the aquatic ecosystem are temperature, TDS, pH and dissolved oxygen, depth, and turbidity. High contents of ammonium ions are observed in the ecosystem. The concentration of dissolved inorganic phosphorus is 23.6% of total phosphorus. The ratio of PO (permanganate oxidizing ability of organic matter) to COD (chemical oxygen demand) indicates active processes of production, mineralization, and transformation of organic matter in the water body. Carotenoids prevail in planktonic pigments. The chlorophyll a amount is insignificant. The chlorophyll b content increases from July to September. Currently, Lake Arey belongs to the α-mesotrophic type of water body. However, increased anthropogenic load and high-water years can promote eutrophication processes.

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