This significant contribution of HS to the DOM pool is due to the fact that, in wetland soils, the main source of DOM originates from microbial decomposition of vascular plant detritus that is subjected to humification processes and turned into humic
material (Calvet et al.
TABLE 1: Organic carbon (C) content on 0-40 cm soil layer in the fulvic acids (AF), humic
acids (AH) and humin (HUM) of humic
substances and sum of these three fractions (SOMA) on four situations of soil use in a Humic
Dystrupept in southern Brazilian highlands.
The highest values of Hum found in CN1 are due to the lower disturbance level of the area, which promotes greater polymerization of humic
acid (HA) levels were used including H0 (without HA), H1 (2.
The use of humic
substances in Brazil is recent and has followed the recommendations of manufacturers, which are mostly from abroad; this situation has caused users to apply these substances, initially, in the same way as in other countries, followed by empirical adjustments by the farmers.
Fulvic and humic
acid are acidic organic compounds contained in peat and lignite, which are types of humic
Fulvic acid is lower molecular weight macromolecule, soluble at all pH values, mixture of yellow to brown color, These molecules are known to be heterogeneous polyacids with polymeric structure formed by different types of functional groups like aliphatic and aromatic organic acids having many aromatic rings attached to (carboxyl, phenols, quinones and semiquinones) [5,8,9,12] and the number of oxygen containing functional groups is more than humic
2008) found that humic
acid application increases the flower quality and diameter, plant height, and vase life in Gebera cut flower by restricting the growth of pathogenic bacteria.
A study with green swordtail (Xiphophorus helleri) has been the only to report some beneficial effect on fish growth for humic
substances (MEINELT et al.
Modern irrigation systems were the optimum irrigation method in the area conditions, whereas organic fertilizers like humic
acid and amino acids widely used in the sandy soils as foliar application.
Keywords: Montmorillonite clay; Adsorption of Pb(II); Humic
acid; Fixed pH; Spectrophotometric method.
exch] in the soil by humic
compounds has affected on P-soluble in the soil, both desorption and adsorption of P.