Loading…
Humic Substances: Hypotheses and Reality (a Review)
The term humic substances (HS) refers to a group of heterogeneous, dark-colored polydisperse substances found in soils, peats, natural waters, and sediments. It is hypothesized that HSs are formed as a result of degradation and transformation of biomolecules of organic residues and free radical cond...
Saved in:
Published in: | Eurasian soil science 2021-12, Vol.54 (12), p.1826-1854 |
---|---|
Main Authors: | , , , , |
Format: | Article |
Language: | English |
Subjects: | |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
cited_by | cdi_FETCH-LOGICAL-c355t-f8318946216876710f2490cab3b3de97ceaaa999b6fcafd3ae56343c7a5c26613 |
---|---|
cites | cdi_FETCH-LOGICAL-c355t-f8318946216876710f2490cab3b3de97ceaaa999b6fcafd3ae56343c7a5c26613 |
container_end_page | 1854 |
container_issue | 12 |
container_start_page | 1826 |
container_title | Eurasian soil science |
container_volume | 54 |
creator | Zavarzina, A. G. Danchenko, N. N. Demin, V. V. Artemyeva, Z. S. Kogut, B. M. |
description | The term humic substances (HS) refers to a group of heterogeneous, dark-colored polydisperse substances found in soils, peats, natural waters, and sediments. It is hypothesized that HSs are formed as a result of degradation and transformation of biomolecules of organic residues and free radical condensation reactions (a process called humification). Humic substances are classified as a special category of natural compounds that are dissimilar to the biomolecules of plant and microbial tissues, and are resistant to biodegradation. On the basis of their solubility in alkalis, HSs are divided into humic acids (HAs, soluble, precipitated at pH < 2), fulvic acids (FAs, soluble at all pH values), and humin (insoluble residue). The review provides a critical analysis of the HS terminology and nomenclature, the method of extraction of HS from natural objects, and the hypotheses describing their formation. The ambiguity and duality of the concept of HSs (specific compounds and the sum of operational fractions) are demonstrated, as well as an arbitrary character of the division of organic matter (OM) into the dark-colored compounds of poorly defined structure (HSs) and the substances with a known structure (non-HSs). The interpretation of HSs as mass products of a secondary synthesis requires revision. The possibility of extracellular free radical reactions in soils leaves no doubt; however, a quantitative contribution of the corresponding products to the natural OM has not been established yet. The traditional alkaline extraction should be considered as a method for isolation of hydrophilic polar substances, while the precipitation with acid as their concentration for further analysis. The historical names of humic fractions (HAs, FAs, and humin) should be retained as well-established generic terms and names of the preparations obtained in a certain way without attaching unique features and specificity to all components of these fractions. The C
HA
/C
FA
(or C
HA
/C
org
) ratios are simple and convenient indicators of the types of humus reflecting bioclimatic conditions of its formation. |
doi_str_mv | 10.1134/S1064229321120164 |
format | article |
fullrecord | <record><control><sourceid>gale_proqu</sourceid><recordid>TN_cdi_proquest_journals_2613301702</recordid><sourceformat>XML</sourceformat><sourcesystem>PC</sourcesystem><galeid>A718429154</galeid><sourcerecordid>A718429154</sourcerecordid><originalsourceid>FETCH-LOGICAL-c355t-f8318946216876710f2490cab3b3de97ceaaa999b6fcafd3ae56343c7a5c26613</originalsourceid><addsrcrecordid>eNp1kE9LAzEQxYMoWKsfwNuCFz1szeTfbryVolYQBKvgbclmJ3VLu1uTXaXf3pQVPIjkkGHe-80kj5BzoBMALq4XQJVgTHMGwCgocUBGIKVKQcu3w1hHOd3rx-QkhBWlPM9FPiJ83m9qmyz6MnSmsRhukvlu23bvGDAkpqmSZzTrutsllyaWnzV-XZ2SI2fWAc9-7jF5vbt9mc3Tx6f7h9n0MbVcyi51OYdcC8VA5ZnKgDomNLWm5CWvUGcWjTFa61I5a1zFDUrFBbeZkZYpBXxMLoa5W99-9Bi6YtX2vokrCxZlTiGjLLomg2tp1ljUjWs7b2w8FcaftQ26OvanGeSCaZAiAjAA1rcheHTF1tcb43cF0GIfZvEnzMiwgQnR2yzR_z7lf-gbqp9zNA</addsrcrecordid><sourcetype>Aggregation Database</sourcetype><iscdi>true</iscdi><recordtype>article</recordtype><pqid>2613301702</pqid></control><display><type>article</type><title>Humic Substances: Hypotheses and Reality (a Review)</title><source>Springer Link</source><creator>Zavarzina, A. G. ; Danchenko, N. N. ; Demin, V. V. ; Artemyeva, Z. S. ; Kogut, B. M.</creator><creatorcontrib>Zavarzina, A. G. ; Danchenko, N. N. ; Demin, V. V. ; Artemyeva, Z. S. ; Kogut, B. M.</creatorcontrib><description>The term humic substances (HS) refers to a group of heterogeneous, dark-colored polydisperse substances found in soils, peats, natural waters, and sediments. It is hypothesized that HSs are formed as a result of degradation and transformation of biomolecules of organic residues and free radical condensation reactions (a process called humification). Humic substances are classified as a special category of natural compounds that are dissimilar to the biomolecules of plant and microbial tissues, and are resistant to biodegradation. On the basis of their solubility in alkalis, HSs are divided into humic acids (HAs, soluble, precipitated at pH < 2), fulvic acids (FAs, soluble at all pH values), and humin (insoluble residue). The review provides a critical analysis of the HS terminology and nomenclature, the method of extraction of HS from natural objects, and the hypotheses describing their formation. The ambiguity and duality of the concept of HSs (specific compounds and the sum of operational fractions) are demonstrated, as well as an arbitrary character of the division of organic matter (OM) into the dark-colored compounds of poorly defined structure (HSs) and the substances with a known structure (non-HSs). The interpretation of HSs as mass products of a secondary synthesis requires revision. The possibility of extracellular free radical reactions in soils leaves no doubt; however, a quantitative contribution of the corresponding products to the natural OM has not been established yet. The traditional alkaline extraction should be considered as a method for isolation of hydrophilic polar substances, while the precipitation with acid as their concentration for further analysis. The historical names of humic fractions (HAs, FAs, and humin) should be retained as well-established generic terms and names of the preparations obtained in a certain way without attaching unique features and specificity to all components of these fractions. The C
HA
/C
FA
(or C
HA
/C
org
) ratios are simple and convenient indicators of the types of humus reflecting bioclimatic conditions of its formation.</description><identifier>ISSN: 1064-2293</identifier><identifier>EISSN: 1556-195X</identifier><identifier>DOI: 10.1134/S1064229321120164</identifier><language>eng</language><publisher>Moscow: Pleiades Publishing</publisher><subject>Alkalis ; Bioclimatology ; Biodegradation ; Biomolecules ; Colour ; Condensates ; Decomposing organic matter ; Earth and Environmental Science ; Earth Sciences ; Extracellular ; Fractions ; Free radicals ; Fulvic acids ; Geotechnical Engineering & Applied Earth Sciences ; Humic acid ; Humic acids ; Humic substances ; Humification ; Humus ; Hypotheses ; Microorganisms ; Natural waters ; Nomenclature ; Object recognition ; Organic matter ; pH effects ; Residues ; Sediments ; Soil ; Soil Chemistry ; Soils ; Specificity</subject><ispartof>Eurasian soil science, 2021-12, Vol.54 (12), p.1826-1854</ispartof><rights>Pleiades Publishing, Ltd. 2021. ISSN 1064-2293, Eurasian Soil Science, 2021, Vol. 54, No. 12, pp. 1826–1854. © Pleiades Publishing, Ltd., 2021. Russian Text © The Author(s), 2021, published in Pochvovedenie, 2021, No. 12, pp. 1449–1480.</rights><rights>COPYRIGHT 2021 Springer</rights><lds50>peer_reviewed</lds50><woscitedreferencessubscribed>false</woscitedreferencessubscribed><citedby>FETCH-LOGICAL-c355t-f8318946216876710f2490cab3b3de97ceaaa999b6fcafd3ae56343c7a5c26613</citedby><cites>FETCH-LOGICAL-c355t-f8318946216876710f2490cab3b3de97ceaaa999b6fcafd3ae56343c7a5c26613</cites></display><links><openurl>$$Topenurl_article</openurl><openurlfulltext>$$Topenurlfull_article</openurlfulltext><thumbnail>$$Tsyndetics_thumb_exl</thumbnail><link.rule.ids>314,777,781,27905,27906</link.rule.ids></links><search><creatorcontrib>Zavarzina, A. G.</creatorcontrib><creatorcontrib>Danchenko, N. N.</creatorcontrib><creatorcontrib>Demin, V. V.</creatorcontrib><creatorcontrib>Artemyeva, Z. S.</creatorcontrib><creatorcontrib>Kogut, B. M.</creatorcontrib><title>Humic Substances: Hypotheses and Reality (a Review)</title><title>Eurasian soil science</title><addtitle>Eurasian Soil Sc</addtitle><description>The term humic substances (HS) refers to a group of heterogeneous, dark-colored polydisperse substances found in soils, peats, natural waters, and sediments. It is hypothesized that HSs are formed as a result of degradation and transformation of biomolecules of organic residues and free radical condensation reactions (a process called humification). Humic substances are classified as a special category of natural compounds that are dissimilar to the biomolecules of plant and microbial tissues, and are resistant to biodegradation. On the basis of their solubility in alkalis, HSs are divided into humic acids (HAs, soluble, precipitated at pH < 2), fulvic acids (FAs, soluble at all pH values), and humin (insoluble residue). The review provides a critical analysis of the HS terminology and nomenclature, the method of extraction of HS from natural objects, and the hypotheses describing their formation. The ambiguity and duality of the concept of HSs (specific compounds and the sum of operational fractions) are demonstrated, as well as an arbitrary character of the division of organic matter (OM) into the dark-colored compounds of poorly defined structure (HSs) and the substances with a known structure (non-HSs). The interpretation of HSs as mass products of a secondary synthesis requires revision. The possibility of extracellular free radical reactions in soils leaves no doubt; however, a quantitative contribution of the corresponding products to the natural OM has not been established yet. The traditional alkaline extraction should be considered as a method for isolation of hydrophilic polar substances, while the precipitation with acid as their concentration for further analysis. The historical names of humic fractions (HAs, FAs, and humin) should be retained as well-established generic terms and names of the preparations obtained in a certain way without attaching unique features and specificity to all components of these fractions. The C
HA
/C
FA
(or C
HA
/C
org
) ratios are simple and convenient indicators of the types of humus reflecting bioclimatic conditions of its formation.</description><subject>Alkalis</subject><subject>Bioclimatology</subject><subject>Biodegradation</subject><subject>Biomolecules</subject><subject>Colour</subject><subject>Condensates</subject><subject>Decomposing organic matter</subject><subject>Earth and Environmental Science</subject><subject>Earth Sciences</subject><subject>Extracellular</subject><subject>Fractions</subject><subject>Free radicals</subject><subject>Fulvic acids</subject><subject>Geotechnical Engineering & Applied Earth Sciences</subject><subject>Humic acid</subject><subject>Humic acids</subject><subject>Humic substances</subject><subject>Humification</subject><subject>Humus</subject><subject>Hypotheses</subject><subject>Microorganisms</subject><subject>Natural waters</subject><subject>Nomenclature</subject><subject>Object recognition</subject><subject>Organic matter</subject><subject>pH effects</subject><subject>Residues</subject><subject>Sediments</subject><subject>Soil</subject><subject>Soil Chemistry</subject><subject>Soils</subject><subject>Specificity</subject><issn>1064-2293</issn><issn>1556-195X</issn><fulltext>true</fulltext><rsrctype>article</rsrctype><creationdate>2021</creationdate><recordtype>article</recordtype><recordid>eNp1kE9LAzEQxYMoWKsfwNuCFz1szeTfbryVolYQBKvgbclmJ3VLu1uTXaXf3pQVPIjkkGHe-80kj5BzoBMALq4XQJVgTHMGwCgocUBGIKVKQcu3w1hHOd3rx-QkhBWlPM9FPiJ83m9qmyz6MnSmsRhukvlu23bvGDAkpqmSZzTrutsllyaWnzV-XZ2SI2fWAc9-7jF5vbt9mc3Tx6f7h9n0MbVcyi51OYdcC8VA5ZnKgDomNLWm5CWvUGcWjTFa61I5a1zFDUrFBbeZkZYpBXxMLoa5W99-9Bi6YtX2vokrCxZlTiGjLLomg2tp1ljUjWs7b2w8FcaftQ26OvanGeSCaZAiAjAA1rcheHTF1tcb43cF0GIfZvEnzMiwgQnR2yzR_z7lf-gbqp9zNA</recordid><startdate>20211201</startdate><enddate>20211201</enddate><creator>Zavarzina, A. G.</creator><creator>Danchenko, N. N.</creator><creator>Demin, V. V.</creator><creator>Artemyeva, Z. S.</creator><creator>Kogut, B. M.</creator><general>Pleiades Publishing</general><general>Springer</general><general>Springer Nature B.V</general><scope>AAYXX</scope><scope>CITATION</scope><scope>7QL</scope><scope>7ST</scope><scope>7T7</scope><scope>7U9</scope><scope>7UA</scope><scope>8FD</scope><scope>C1K</scope><scope>F1W</scope><scope>FR3</scope><scope>H94</scope><scope>H96</scope><scope>L.G</scope><scope>M7N</scope><scope>P64</scope><scope>SOI</scope></search><sort><creationdate>20211201</creationdate><title>Humic Substances: Hypotheses and Reality (a Review)</title><author>Zavarzina, A. G. ; Danchenko, N. N. ; Demin, V. V. ; Artemyeva, Z. S. ; Kogut, B. M.</author></sort><facets><frbrtype>5</frbrtype><frbrgroupid>cdi_FETCH-LOGICAL-c355t-f8318946216876710f2490cab3b3de97ceaaa999b6fcafd3ae56343c7a5c26613</frbrgroupid><rsrctype>articles</rsrctype><prefilter>articles</prefilter><language>eng</language><creationdate>2021</creationdate><topic>Alkalis</topic><topic>Bioclimatology</topic><topic>Biodegradation</topic><topic>Biomolecules</topic><topic>Colour</topic><topic>Condensates</topic><topic>Decomposing organic matter</topic><topic>Earth and Environmental Science</topic><topic>Earth Sciences</topic><topic>Extracellular</topic><topic>Fractions</topic><topic>Free radicals</topic><topic>Fulvic acids</topic><topic>Geotechnical Engineering & Applied Earth Sciences</topic><topic>Humic acid</topic><topic>Humic acids</topic><topic>Humic substances</topic><topic>Humification</topic><topic>Humus</topic><topic>Hypotheses</topic><topic>Microorganisms</topic><topic>Natural waters</topic><topic>Nomenclature</topic><topic>Object recognition</topic><topic>Organic matter</topic><topic>pH effects</topic><topic>Residues</topic><topic>Sediments</topic><topic>Soil</topic><topic>Soil Chemistry</topic><topic>Soils</topic><topic>Specificity</topic><toplevel>peer_reviewed</toplevel><toplevel>online_resources</toplevel><creatorcontrib>Zavarzina, A. G.</creatorcontrib><creatorcontrib>Danchenko, N. N.</creatorcontrib><creatorcontrib>Demin, V. V.</creatorcontrib><creatorcontrib>Artemyeva, Z. S.</creatorcontrib><creatorcontrib>Kogut, B. M.</creatorcontrib><collection>CrossRef</collection><collection>Bacteriology Abstracts (Microbiology B)</collection><collection>Environment Abstracts</collection><collection>Industrial and Applied Microbiology Abstracts (Microbiology A)</collection><collection>Virology and AIDS Abstracts</collection><collection>Water Resources Abstracts</collection><collection>Technology Research Database</collection><collection>Environmental Sciences and Pollution Management</collection><collection>ASFA: Aquatic Sciences and Fisheries Abstracts</collection><collection>Engineering Research Database</collection><collection>AIDS and Cancer Research Abstracts</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) 2: Ocean Technology, Policy & Non-Living Resources</collection><collection>Aquatic Science & Fisheries Abstracts (ASFA) Professional</collection><collection>Algology Mycology and Protozoology Abstracts (Microbiology C)</collection><collection>Biotechnology and BioEngineering Abstracts</collection><collection>Environment Abstracts</collection><jtitle>Eurasian soil science</jtitle></facets><delivery><delcategory>Remote Search Resource</delcategory><fulltext>fulltext</fulltext></delivery><addata><au>Zavarzina, A. G.</au><au>Danchenko, N. N.</au><au>Demin, V. V.</au><au>Artemyeva, Z. S.</au><au>Kogut, B. M.</au><format>journal</format><genre>article</genre><ristype>JOUR</ristype><atitle>Humic Substances: Hypotheses and Reality (a Review)</atitle><jtitle>Eurasian soil science</jtitle><stitle>Eurasian Soil Sc</stitle><date>2021-12-01</date><risdate>2021</risdate><volume>54</volume><issue>12</issue><spage>1826</spage><epage>1854</epage><pages>1826-1854</pages><issn>1064-2293</issn><eissn>1556-195X</eissn><abstract>The term humic substances (HS) refers to a group of heterogeneous, dark-colored polydisperse substances found in soils, peats, natural waters, and sediments. It is hypothesized that HSs are formed as a result of degradation and transformation of biomolecules of organic residues and free radical condensation reactions (a process called humification). Humic substances are classified as a special category of natural compounds that are dissimilar to the biomolecules of plant and microbial tissues, and are resistant to biodegradation. On the basis of their solubility in alkalis, HSs are divided into humic acids (HAs, soluble, precipitated at pH < 2), fulvic acids (FAs, soluble at all pH values), and humin (insoluble residue). The review provides a critical analysis of the HS terminology and nomenclature, the method of extraction of HS from natural objects, and the hypotheses describing their formation. The ambiguity and duality of the concept of HSs (specific compounds and the sum of operational fractions) are demonstrated, as well as an arbitrary character of the division of organic matter (OM) into the dark-colored compounds of poorly defined structure (HSs) and the substances with a known structure (non-HSs). The interpretation of HSs as mass products of a secondary synthesis requires revision. The possibility of extracellular free radical reactions in soils leaves no doubt; however, a quantitative contribution of the corresponding products to the natural OM has not been established yet. The traditional alkaline extraction should be considered as a method for isolation of hydrophilic polar substances, while the precipitation with acid as their concentration for further analysis. The historical names of humic fractions (HAs, FAs, and humin) should be retained as well-established generic terms and names of the preparations obtained in a certain way without attaching unique features and specificity to all components of these fractions. The C
HA
/C
FA
(or C
HA
/C
org
) ratios are simple and convenient indicators of the types of humus reflecting bioclimatic conditions of its formation.</abstract><cop>Moscow</cop><pub>Pleiades Publishing</pub><doi>10.1134/S1064229321120164</doi><tpages>29</tpages></addata></record> |
fulltext | fulltext |
identifier | ISSN: 1064-2293 |
ispartof | Eurasian soil science, 2021-12, Vol.54 (12), p.1826-1854 |
issn | 1064-2293 1556-195X |
language | eng |
recordid | cdi_proquest_journals_2613301702 |
source | Springer Link |
subjects | Alkalis Bioclimatology Biodegradation Biomolecules Colour Condensates Decomposing organic matter Earth and Environmental Science Earth Sciences Extracellular Fractions Free radicals Fulvic acids Geotechnical Engineering & Applied Earth Sciences Humic acid Humic acids Humic substances Humification Humus Hypotheses Microorganisms Natural waters Nomenclature Object recognition Organic matter pH effects Residues Sediments Soil Soil Chemistry Soils Specificity |
title | Humic Substances: Hypotheses and Reality (a Review) |
url | http://sfxeu10.hosted.exlibrisgroup.com/loughborough?ctx_ver=Z39.88-2004&ctx_enc=info:ofi/enc:UTF-8&ctx_tim=2025-01-19T08%3A56%3A40IST&url_ver=Z39.88-2004&url_ctx_fmt=infofi/fmt:kev:mtx:ctx&rfr_id=info:sid/primo.exlibrisgroup.com:primo3-Article-gale_proqu&rft_val_fmt=info:ofi/fmt:kev:mtx:journal&rft.genre=article&rft.atitle=Humic%20Substances:%20Hypotheses%20and%20Reality%20(a%20Review)&rft.jtitle=Eurasian%20soil%20science&rft.au=Zavarzina,%20A.%20G.&rft.date=2021-12-01&rft.volume=54&rft.issue=12&rft.spage=1826&rft.epage=1854&rft.pages=1826-1854&rft.issn=1064-2293&rft.eissn=1556-195X&rft_id=info:doi/10.1134/S1064229321120164&rft_dat=%3Cgale_proqu%3EA718429154%3C/gale_proqu%3E%3Cgrp_id%3Ecdi_FETCH-LOGICAL-c355t-f8318946216876710f2490cab3b3de97ceaaa999b6fcafd3ae56343c7a5c26613%3C/grp_id%3E%3Coa%3E%3C/oa%3E%3Curl%3E%3C/url%3E&rft_id=info:oai/&rft_pqid=2613301702&rft_id=info:pmid/&rft_galeid=A718429154&rfr_iscdi=true |