Abstract

RIOS CABRERA, María M; RUIZ DAGER, Magaly; MADURO ROJAS, Rubén  and  GARCIA, Hugo. Exploratory Study of Chemical Properties of Soils Susceptible to Debris Flows in the Maracay River Basin, Aragua State. Terra [online]. 2016, vol.32, n.51, pp.69-91. ISSN 1012-7089.

An exploratory study on soil chemical properties of the river basin Maracay (Aragua, Venezuela) was conducted to estimate the relationship between them and the risk of shallow landslides. By univariate descriptive analysis mean, pH, organic matter content (OM), calcium, magnesium, phosphorus, potassium and sodium, were evaluated. It was found that the variability of chemical properties is extremely high. The coefficients of variation ranged from 18 % to more than 100 %. The pH and magnesium were the variables which had lower levels of variability. In soils with granular structure, values corresponding to the percentage of OM, calcium and potassium were lower than loam soil. High positive correlations were found between the P content and pH, OM and K, pH and Ca, Ca and Mg. The desaturation of bases in the exchange complex in the high places of the toposequence, leads to the adsorption of toxic elements for the plants, such as aluminum, and also promotes the formation of secondary minerals of the 1:1 type, which tend to have little plastic characteristics in the presence of a specific water content, which makes these soils susceptible to being mobilized and transformed into a socio-natural element of risk, that can be aggravated by excessive anthropogenic intervention.

Keywords : debris flows; Maracay river basin; toposequence; chemical properties.