Organic Matter

On the soil, the role of organic matter is of great importance. The richness of the soil depends on the quality of both its physical and chemical propertier, and in both, organic matter plays an essential role.

The number of microorganisms, small insects, arthropods, vertebrates, living cells, organic remains, in short, the living organisms that develop within the edaphic environment, create extraordinary biological activity. It is the “living” side, that comes from different sources: animals, vegetables, microbes …

It acts on the “dead” side, which constantly subjected to decomposition processes, transformations and re-synthesis. Thus, the fresh organic matter, recently incorporated into the soil, once in direct contact, initiates a process of decomposition caused by the microorganisms found in the very same soil, generating an important biological activity responsible for many of the beneficial properties of the soil.

In summary, the organic matter itself is renewed and decomposed, and through this decomposition the soil becomes consistency, mineral wealth and the ideal substrate for our crops.
The amount of organic matter contained in mineral soil is small, varying from 1 to 6% on the surface area and much less in the subsoil. Despite its small quantity of it, its influence on the soils’ properties is very big:

  • Improvement of structure and aggregates of mineral particles. Increase aeration and the amount of water that soil can hold: Organic matter improves the bond between structural aggregates. Both clay and sandy soils improve the properties of these, increasing the number of macropores in the first and micropores in the second, thus contributing to better aeration in heavy soils (clays) and better water retention capacity in the sandy soils, which are excessively loose. This feature also improves resistance to erosion and loss of agricultural land, especially by surface runoff.
  • It can retain ions; among them, some soil micronutrients: Both the FA and the HA are considered hydrophilic, electrically charged colloids, cation and anion detectors, preventing their loss through washing. In terms of the FA, the negative charges are neutralized by Ca ++ and Mg ++ forming part of the interchangeable cation of the soil reservoir. These become available through the plant’s root system, since, otherwise, they could be lost through leaching, especially in climates of frequent rainfall and in unstructured soils.

These characteristics, are responsible for the soil’s increase in the CEC (cation exchange capacity).

  • Chelating effect of humic and fulvic acids on Fe, Mn, Zn and Cu: Directly related to the previous section, and due to the molecular composition of humic and fulvic acids, they have a chelating effect on some microelements that give greater availability for root absorption and use in the multiple metabolic pathways that form them.
  • It is a source of nutrients (N, P, S): During the decomposition of organic matter and other microbiological processes associated with it, there is a release of different molecules that contain macro-elements which are assimilable by the root. This addition of organic matter is considered to be a slow-release mineral contribution, in other words, a mineral “reservoir” that gradually provides elements such as N, P and S, to name a few.

They contribute to the absorption of energy and increase the temperature of the soil:

  • Biologically, microbiological activity generates energy. Physically, the dark color absorbs radiation. Both processes raise the temperature of the soil and, therefore, contribute, among other things, to a greater root proliferation.
  • Regulation of soil pH.
  • Growth stimulants: Several researchers associate the presence of HA and FA with potential phytohormone precursors, as well as with the potential to transform substances that are potentially toxic for plants.