The role of exogenous humic and fulvic acids in iodine biofortification in spinach (Spinacia oleracea L.)

A hypothesis was verified that forest floor chemistry varies according to position within the windthrow (mound, pit, or control). A parallel assessment was made of differences in the chemistry of horizons and their forms. A total number of 1720 windthrows were studied in the fir–beech primeval forest in the flysch zone of the Western Carpathians. A total of 100 samples were taken on three positions from the following horizons and their forms (in brackets): litter, fermented (amphigenous, zoogenous, or mycogenous), humification (unresolved, zoogenous, residues, or humic), and mineral. A random sampling eliminated the effect of correlation between the horizons and positions. Parameters assessed were Q4/6, HA/FA, C-forms, total N, P, K, and Mg contents, soil reaction, and cation-exchange capacity. The positions exhibited a significant difference in the forest floor chemistry even at a level of horizon forms. The position’s significance decreased with the horizon depth. Organic horizons in the pit, in particular, exhibited the lowest content of total humic substances, fulvic acids, and the lowest colour coefficient values. However, the mineral horizon showed no significant differences between the positions within the windthrow. Compared with other humus types, the decomposing wood mass did not exhibit a different ratio of humic and fulvic acids.

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Influence of humus acids on mobility and biological availability of iron, zinc and copper

Agricultural science and practice ◽

10.15407/agrisp2.01.073 ◽

2015 ◽

Vol 2 (1) ◽

pp. 73-78

Author(s):

A. Fateev ◽

D. Semenov ◽

K. Smirnova ◽

A. Shemet

Keyword(s):

Trace Elements ◽

Organic Matter ◽

Soil Organic Matter ◽

Humic Acids ◽

Fulvic Acids ◽

Sand Culture ◽

Humic And Fulvic Acids ◽

Cultivation Medium ◽

Mobile Forms

Soil organic matter is known as an important condition for the mobility of trace elements in soils, their geo- chemical migration and availability to plants. However, various components of soil organic matter have differ- ent effect on these processes due to their signifi cant differences in structure and properties. Aim. To establish the role of humic and fulvic acids in the process of formation of microelement mobility in soils and their accu- mulation in plants. Methods. A model experiment with sand culture was used to investigate the release of trace elements from preparations of humic and fulvic acids and their uptake by oat plants. Results. It was found that among biologically needed elements humic acids are enriched with iron, fulvic acids – with zinc, and copper distribution between these two groups of substances may be characterized as even. These elements have un- equal binding power with components of soil organic matter, as evidenced by their release into the cultivation medium and accumulation in plants. In the composition of fulvic acids zink has the most mobility – up to 95 % of this element is in the form, accessible for plants; the lowest mobility was demonstrated by copper in the composition with humic acids, for which no signifi cant changes in the concentration of mobile forms in the substrate and in the introduction to the test culture were registered. Despite signifi cantly higher iron content in humic acids, the application of fulvic acids in the cultivation medium provides a greater increase in the con- centration of mobile forms of this element. Conclusions. The results confi rm the important role of organic sub- stances of fulvic nature in the formation of zinc and iron mobility in the soil and their accumulation in plants.

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Radio-Labelled Humic Materials in Migration Studies

MRS Proceedings ◽

10.1557/proc-294-811 ◽

1992 ◽

Vol 294 ◽

Cited By ~ 2

Author(s):

Lars Carlsen ◽

Pia Lassen ◽

Peter Warwick ◽

Amanda Randall

Keyword(s):

Environmental Fate ◽

Fulvic Acids ◽

Migration Studies ◽

Humic And Fulvic Acids ◽

Humic Material ◽

Naturally Occurring ◽

Significant Strength ◽

Soils And Sediments ◽

Humic Materials

ABSTRACTHumic- and fulvic acids are able to complex polyvalent metal ions, e.g. radionuclides, leading to soluble complexes of significant strength, thereby decreasing the sorption of these compounds to soils and sediments. The interaction of humic materials with radionuclides may significantly influence the availability and transport of the latter in the environment. Typically, studies along these lines have focussed almost exclusively on the radionuclides, whereas the actual role of the humic material has been elucidated only indirectly. In order directly to study the behaviour of the naturally occurring organic macro-molecules in relation to the environmental fate of radionuclides, radio-labelled humic- and fulvic acids can advantageously be applied. Radio-labels such as 14C and 125I have successfully been covalently incorporated in humic- and fulvic acids. Labelling of humic substances as well as preliminary migration studies are discussed

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