Changes in structural characteristics of humic and fulvic acids under chlorination and their association with trihalomethanes and haloacetic acids formation

Author(s):  
Hang Vo-Minh Nguyen ◽  
Han-Saem Lee ◽  
Su-Young Lee ◽  
Jin Hur ◽  
Hyun-Sang Shin
2021 ◽  
Author(s):  
Viia Lepane ◽  
Helen Otsep ◽  
Lech Wojciech Szajdak ◽  
Marek Szczepanski

<p>UV spectroscopy is extensively used for the quantitative analysis of natural macromolecules because of simplicity. As a qualitative method it is not very selective. The absorption spectra of organic macromolecules are generally broad bands without distinct peaks decreasing with the increasing wavelength making thus impossible to draw conclusions about exact chemical composition. However certain optical properties enable to obtain information about the organic matter transformation and changes in soils.</p><p>In present study soil samples from different depths were investigated by UV spectroscopic methods to measure the absorbance ratios at several wavelengths that could be related to chemical properties of the organic matter, for example the aromaticity, average molecular mass, functional groups, etc. The aim was to study the changes in structural characteristics of humic acids in soil profiles by using their UV absorbance ratios (A254/A436, A280/A350, A470/A664, A254/A354, A254/A204). The top layer of the soil was also characterized by comparing the structure of humic and fulvic acids and unfractionated dissolved organic matter. The spectra and molecular masses were additionally obtained by high performance size exclusion chromatography (HPSEC) with diode array detection.</p><p>Our results showed that there is a systematic change in the absorbance ratios at different wavelengths of humic- and fulvic acids and dissolved organic matter spectra in the soil profile that indicates to structural changes in the soil in time. The comparison of all fractions indicated that fulvic acid and unfractionated organic matter are structurally more similar to each other than to humic acid. Although the values obtained by two studied methods (UV spectroscopy and HPSEC) did not give the same values for the absorbance ratios, the correlations are mostly comparable and therefore, both methods can be used to estimate the changes of structural properties in soil.</p>


Author(s):  
Ramiro Remigio Gaibor Fernández ◽  
Abraham Adalberto Bayas Zamora ◽  
Galo Israel Muñoz Sánchez ◽  
Cristhian Adrián Rivas Santacruz

The objective of the present investigation was to evaluate the physical characteristics of the vermicompost and the quality of the purine of the red Californian (Eisenia foetida) using different substrates of feed for these worms. For this purpose, nine treatments were studied: 75% African palm rachis + 25% cattle manure, 50% African palm rachis + 50% cattle manure, 25% African palm rachis + 75% livestock manure, 50% manure of cattle, 50% of manure of cattle, 25% of manure of cattle, 50% of manure of cattle, 50% of manure of cattle, 50% of rach of coconut + 50% of manure of Livestock, 25% coccus rachis + 75% livestock manure. The substrate made up of 50% of rachis of coconut and 50% of livestock manure can be used in nurseries or nurseries for being the one that registered a value of pH 7.3 plus the closest to the neutral compared to the others, besides this (75% of oil palm rachis and 25% of cattle manure) showed a higher content of humic and fulvic acids (0.87 and 0.45 p / p, respectively), compounds that are important for agriculture by stimulating plant growth, in addition to this reflection 0.06% sulfur content, 4.0 ppm boron, 7.0 ppm copper, 47.5 ppm iron, 6.0 ppm manganese, with a presence of microorganisms of the species Trichoderma, Penicillium, Cladosporium sp. in amounts of 1.91x105 UFC / ml, however in this substrate was obtained between 13.3 and 43.5% less liquid slurry in Comparison with other treatments.


2013 ◽  
Vol 24 (2) ◽  
pp. 106-112 ◽  
Author(s):  
Dariusz Man ◽  
Izabella Pisarek ◽  
Michał Braczkowski ◽  
Barbara Pytel ◽  
Ryszard Olchawa

1989 ◽  
Vol 34 (1) ◽  
pp. 68-81 ◽  
Author(s):  
Kendall L. Carder ◽  
Robert G. Steward ◽  
George R. Harvey ◽  
Peter B. Ortner

2021 ◽  
Author(s):  
Milanka Radulovic ◽  
◽  
Svetlana Mitrovski

Peat is a natural substrate for growth of microorganisms because it is rich in compounds that microorganisms can use as sources of carbon, nitrogen and growth factors. Peat originating from Vlasina lake in Eastern Serbia is especially rich in organic matter. The content of humic substances (humic acid, fulvic acid and humine) is almost twice that found in other peat-rich regions of similar origin and geochemical age. Humic and fluvic acids are known to promote microbial growth. In this work, humic and fulvic acids were first extracted from Vlasina lake peat and then added to minimal medium (synthetic, low ionic strength medium). The humic substances were added separately and combined in a 1:1 ratio by mass to study their individual and combined effect on microbial growth of Escherichia coli ATCC 25922 (Gr–), Staphyloccocus aureus (Gr+) i Aureobasidium pullulans, strain CH-1. The microbial growth was measured microspectrophotometrically over a 24-hour period and growth curves were obtained for a range of acid concentrations between 25 µg cm-3 and 100 µg cm-3. It was found that both humic and fulvic acids promote the growth of all three microorganisms by up to a maximum of 40%-80% the extent of which varied with the concentration of the acid and the identity of the microorganism. In general, humic acid was found to result in higher microbial growth (at highest concentrations, up to ~80% for all three microbial species).


2007 ◽  
pp. 51-62 ◽  
Author(s):  
Manfred Wolf ◽  
Gunnar Buckau ◽  
Horstr Geckeis ◽  
Ngo Manh Thang ◽  
Enamul Hoque ◽  
...  

2005 ◽  
Vol 34 (3) ◽  
pp. 1131-1137 ◽  
Author(s):  
César Plaza ◽  
Juan C. García-Gil ◽  
Alfredo Polo ◽  
Nicola Senesi ◽  
Gennaro Brunetti

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