Resumo

PAZ, Fernando  e  ETCHEVERS, Jorge. Depth distribution of soil organic carbon in Mexico soils. Terra Latinoam [online]. 2016, vol.34, n.3, pp.339-355. ISSN 2395-8030.

The characterization of the vertical distribution of soil organic carbon (SOC) in Mexican soils is an important assignment, given the accumulated evidence that the SOC can be destabilized by different mechanisms as depth in the prof ile increases. In order to model the SOC variation with depth, a database of SOC from prof iles distributed throughout Mexico was analyzed (INEGI-COLPOS database). This database was f iltered using different restrictions consistent with the objective of developing mathematical models of carbon distribution with depth (z). The statistical adjusted results showed the logarithmic model, SOC (z) = a-b ln (z), being suitable for the planned purpose, so we proceeded to its synthesis. We used the property that a set of lines that intersect at a common point when their parameters are plotted generates a straight line. Based on this scheme it was developed an estimation of the inert organic carbon (IOC) considering the a-b space of the logarithmic model. In addition, to estimate the SOC at different soil depth using the values of SOC from 0 to 30 cm, a method was developed from parameters associated to ecosystems and vegetation types. The results of the exercises carried out to estimate the IOC and organic carbon in the soil depth using only the COS measured in the 0 to 30 cm depth prove to be appropriate and can be implemented operationally.

Palavras-chave : logarithmic model; IOC; SOC 30 cm; ecosystems and vegetation types; COLPOS model.