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3.3 Land use data
In this paragraph the information regarding the land use is expanded under the following
topics:
- Soil types.
- Road infrastructure.

3.3.1 Soil type
Tabasco soils were formed in the Quaternary period of geological time scale which started
some 2,500 million years. This is the last of the geological periods comprising in the recent
period of glacial cycles.
Tabasco soils were formed as a result of:
1. Volcanic eruptions, where the magma rapidly cooled on the surface, solidified and
produced rocks with microscopic crystals, termed, extrusive volcanic rocks.
2. The production of alluvial sands or the Mud Rivers caused after heavy rains or
snowmelt floods caused, as a result of earthquakes or volcanic eruptions that carry
with them silt, sand, rocks, among others.

In the State of Tabasco, the State Forestry Commission, an agency of the Ministry of
Agricultural Development, Forestry and Fisheries of the State, conducted a study of soils in
which the criteria were taken of soil types (drainage, texture, depth and pH), rainfall and
altitude.

Based on this study the comparison was made between the taxonomy of the FAO/UNESCO and
the nomenclature of the Unified Soil Classification System (USCS).

Figure 3.3: Taxonomy of the FAO/UNESCO or the World Reference Base for Soil Resource

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