Humic Acids Formation during Compositing of Plant Remnants in Presence of Calcium Carbonate and Biochar

The investigation of the mechanisms organic matter transformation in compost organic fertilizers is an urgent task of modern soil ecology and soil chemistry. The main components of such fertilizers are newly formed, weakly humified labile humic acids (HAs). The objective of the study is to determine...

Full description

Bibliographic Details
Main Authors: Nataliya Orlova, Elena Orlova, Evgeny Abakumov, Kseniia Smirnova, Serafim Chukov
Format: Article
Language:English
Published: MDPI AG 2022-09-01
Series:Agronomy
Subjects:
Online Access:https://www.mdpi.com/2073-4395/12/10/2275
_version_ 1827652343702749184
author Nataliya Orlova
Elena Orlova
Evgeny Abakumov
Kseniia Smirnova
Serafim Chukov
author_facet Nataliya Orlova
Elena Orlova
Evgeny Abakumov
Kseniia Smirnova
Serafim Chukov
author_sort Nataliya Orlova
collection DOAJ
description The investigation of the mechanisms organic matter transformation in compost organic fertilizers is an urgent task of modern soil ecology and soil chemistry. The main components of such fertilizers are newly formed, weakly humified labile humic acids (HAs). The objective of the study is to determine the mechanism of converting the newly formed HAs into the forms with increased resistance to microbiological and biochemical influences. Obtained during the plant residues decomposition, HAs were studied in the incubation experiment (0, 30, 90 days). Calcium carbonate and biochar produced by rapid pyrolysis from birch and aspen wood, at 550 °C, were used as the composting mixture compounds. Decomposed plant residues—fresh aboveground mass of clover (<i>Trifolium pratense</i> L.), rye (<i>Secale cereale</i> L.), as well as dry oat straw (<i>Avena sativa</i> L.) were the material used for humification. To obtain Has, 0.1 M NaOH and 0.1 M Na<sub>4</sub>P<sub>2</sub>O<sub>7</sub> were used. Then, HAs were separated from fulvic acids (FAs) using a 0.5 M H<sub>2</sub>SO<sub>4</sub>. The amount of labile HAs (HAs1) was estimated by their content in 0.1 M NaOH. The amount of stabilized HAs (HAs2) was calculated by the difference between the HAs content in 0.1 M Na<sub>4</sub>P<sub>2</sub>O<sub>7</sub> and 0.1 M NaOH. Preparation of HAs for elemental composition and NMR analysis was performed according to the International Humic Substances Society’s recommendations. The possibility of converting newly formed HAs into stable forms (calcium humates), whose share in the HAs composition reaches 40–50%, has been shown. However, the mechanism of HAs transformation under the studied reagent’s influence was different. In the presence of calcium carbonate, it is caused by the physicochemical processes of newly formed HAs rearrangement. However, in the presence of biochar, this is due to the humification processes’ intensification and to the increase in the aromatization degree confirmed by the increase in the optical density, as well as by the increase in carbon and oxygen proportion, and by the decrease in hydrogen proportion in HAs molecules. The understanding of HAs formation and transformation mechanisms at the early humification stages can help to optimize the methods of obtaining organic fertilizers.
first_indexed 2024-03-09T20:54:09Z
format Article
id doaj.art-128262c6f1ed42eaa95623d37a7f8ec6
institution Directory Open Access Journal
issn 2073-4395
language English
last_indexed 2024-03-09T20:54:09Z
publishDate 2022-09-01
publisher MDPI AG
record_format Article
series Agronomy
spelling doaj.art-128262c6f1ed42eaa95623d37a7f8ec62023-11-23T22:24:16ZengMDPI AGAgronomy2073-43952022-09-011210227510.3390/agronomy12102275Humic Acids Formation during Compositing of Plant Remnants in Presence of Calcium Carbonate and BiocharNataliya Orlova0Elena Orlova1Evgeny Abakumov2Kseniia Smirnova3Serafim Chukov4Department of Agrochemistry, Faculty of Biology, Saint Petersburg State University, 199178 St. Petersburg, RussiaDepartment of Agrochemistry, Faculty of Biology, Saint Petersburg State University, 199178 St. Petersburg, RussiaDepartment of Applied Ecology, Faculty of Biology, Saint Petersburg State University, 199178 St. Petersburg, RussiaDepartment of Agrochemistry, Faculty of Biology, Saint Petersburg State University, 199178 St. Petersburg, RussiaDepartment of Soil Science and Soil Ecology, Institute of Earth Science, Saint Petersburg State University, 199178 St. Petersburg, RussiaThe investigation of the mechanisms organic matter transformation in compost organic fertilizers is an urgent task of modern soil ecology and soil chemistry. The main components of such fertilizers are newly formed, weakly humified labile humic acids (HAs). The objective of the study is to determine the mechanism of converting the newly formed HAs into the forms with increased resistance to microbiological and biochemical influences. Obtained during the plant residues decomposition, HAs were studied in the incubation experiment (0, 30, 90 days). Calcium carbonate and biochar produced by rapid pyrolysis from birch and aspen wood, at 550 °C, were used as the composting mixture compounds. Decomposed plant residues—fresh aboveground mass of clover (<i>Trifolium pratense</i> L.), rye (<i>Secale cereale</i> L.), as well as dry oat straw (<i>Avena sativa</i> L.) were the material used for humification. To obtain Has, 0.1 M NaOH and 0.1 M Na<sub>4</sub>P<sub>2</sub>O<sub>7</sub> were used. Then, HAs were separated from fulvic acids (FAs) using a 0.5 M H<sub>2</sub>SO<sub>4</sub>. The amount of labile HAs (HAs1) was estimated by their content in 0.1 M NaOH. The amount of stabilized HAs (HAs2) was calculated by the difference between the HAs content in 0.1 M Na<sub>4</sub>P<sub>2</sub>O<sub>7</sub> and 0.1 M NaOH. Preparation of HAs for elemental composition and NMR analysis was performed according to the International Humic Substances Society’s recommendations. The possibility of converting newly formed HAs into stable forms (calcium humates), whose share in the HAs composition reaches 40–50%, has been shown. However, the mechanism of HAs transformation under the studied reagent’s influence was different. In the presence of calcium carbonate, it is caused by the physicochemical processes of newly formed HAs rearrangement. However, in the presence of biochar, this is due to the humification processes’ intensification and to the increase in the aromatization degree confirmed by the increase in the optical density, as well as by the increase in carbon and oxygen proportion, and by the decrease in hydrogen proportion in HAs molecules. The understanding of HAs formation and transformation mechanisms at the early humification stages can help to optimize the methods of obtaining organic fertilizers.https://www.mdpi.com/2073-4395/12/10/2275organic wastecomposthumic substanceshumificationorganic fertilizers
spellingShingle Nataliya Orlova
Elena Orlova
Evgeny Abakumov
Kseniia Smirnova
Serafim Chukov
Humic Acids Formation during Compositing of Plant Remnants in Presence of Calcium Carbonate and Biochar
Agronomy
organic waste
compost
humic substances
humification
organic fertilizers
title Humic Acids Formation during Compositing of Plant Remnants in Presence of Calcium Carbonate and Biochar
title_full Humic Acids Formation during Compositing of Plant Remnants in Presence of Calcium Carbonate and Biochar
title_fullStr Humic Acids Formation during Compositing of Plant Remnants in Presence of Calcium Carbonate and Biochar
title_full_unstemmed Humic Acids Formation during Compositing of Plant Remnants in Presence of Calcium Carbonate and Biochar
title_short Humic Acids Formation during Compositing of Plant Remnants in Presence of Calcium Carbonate and Biochar
title_sort humic acids formation during compositing of plant remnants in presence of calcium carbonate and biochar
topic organic waste
compost
humic substances
humification
organic fertilizers
url https://www.mdpi.com/2073-4395/12/10/2275
work_keys_str_mv AT nataliyaorlova humicacidsformationduringcompositingofplantremnantsinpresenceofcalciumcarbonateandbiochar
AT elenaorlova humicacidsformationduringcompositingofplantremnantsinpresenceofcalciumcarbonateandbiochar
AT evgenyabakumov humicacidsformationduringcompositingofplantremnantsinpresenceofcalciumcarbonateandbiochar
AT kseniiasmirnova humicacidsformationduringcompositingofplantremnantsinpresenceofcalciumcarbonateandbiochar
AT serafimchukov humicacidsformationduringcompositingofplantremnantsinpresenceofcalciumcarbonateandbiochar