Hydrophobic and hydrophilic properties of humic acids from soils under shelterbelts of different ages

Abstract

A comparative investigation of the hydrophobic-hydrophilic properties of humic acids (HA) extracted with 0.1 M Na 4 P 2 O 7 at pH 7 from soils under shelterbelts of different ages [14 years old (young) and 200 years old (old)] and adjoining cultivated fields was carried out with the application of 13 C NMR spectroscopy and hydrophobic interaction chromatography (HIC). The results determined using both methods were in line with the chemical composition of HA. Shelterbelt age was shown to be the principal factor affecting the composition and hydrophobic-hydrophilic properties of HA. HA from soil under the young shelterbelt was found to be less chemically mature and more hydrophilic than HA from the soil of the adjoining cultivated field. By contrast, HA from soil under the old shelterbelt was considerably more chemically mature and hydrophobic than that of the corresponding cultivated field and HA from the soil under the young shelterbelt.

Mutual relations between PAHs derived from atmospheric deposition, enzymatic activity, and humic substances in soils of differently urbanized areas

“…Plowing and other agronomic treatments in arable soils cause the loss of organic matter to varying degrees. Furthermore, accumulated carbon in the topsoil of undisturbed soils remains in a state of dynamic equilibrium with the plant community, which favors the additional protection of its resources, depending on type and age of plant communities (Dinghua et al 2001;Maryganova et al 2010). Older trees produce more organic matter, which can be a potential reason for an increased rate of fulvic acids (Antisari et al 2011).…”

Effectiveness of a shelterbelt in decreasing the level of inorganic elements in agricultural landscape

“…The decrease of their concentrations in the sorptive complex due to excessive leaching seems to be a negative effect. They are available and indispensable nutrients for plants and undoubtedly they significantly participate in biological, physical, chemical, and biochemical processes in soils (Szajdak, 2002;Szajdak & Maryganova, 2009;Maryganova et al, 2010;Szajdak & Gaca, 2010).…”

1H and 13C NMR spectroscopic studies of hexane-extractable lipids from soils under shelterbelts of different age and composition of plants

“…Consequently, the highest content of saturated hydrocarbons and the lowest amount of unsaturated fatty acids in the lipid fraction of the soil under the old shelterbelt indicates the advanced stages of the lipid transformation with the accumulation of stable compounds. It is interesting to note that humic acids separated from the soil under the old shelterbelt are also characterized by the highest content of alkyl C and as a consequence by the highest hydrophobicity and stability compared to those from the soil under the young shelterbelt and soils of adjoining arable fields (Maryganova et al, 2010). The lowest amount of esters of o-phthalic acid in the lipid fraction of this soil is due probably to their destruction in the soil with high biological activity.…”

“…The conversion from arable cropping to shelterbelt was shown to cause the accumulation of soil organic matter (SOM) and changes in chemical structure and physicochemical properties of humic substances with the age of shelterbelts being the principal factor (Szajdak, 2002;Szajdak and Maryganova, 2003;Maryganova et al, 2010).…”