Neosols, relict paleosols, and alterites in the Transmexican Volcanic Belt, Morelos state: Characterization and regional spatial distribution

Abstract

Investigations concerning the pedological linkages between modern soils and paleosequences, as well as the research regarding their spatial distribution and variability dynamics along the landscape are unfortunately very scarce. Both studies can provide, in a geochronological scale, a very useful paradigm to decipher the present and past biotic and abiotic environmental conditions that prevailed in many regions of the world.

The aim of this paper is: (1) to characterize the environment as well as the soil groups and paleosequences located in landscapes of the Transmexican Volcanic Belt, Morelos state, and (2) to explain, relate, and visualize in two dimensions and at a reconnaissance scale, the spatial distribution of soil groups within these landscapes. Such knowledge can provide the basis to establish a unique paleopedological record of late Pleistocene to Holocene environmental conditions in the Transmexican Volcanic Belt.

In our study, the interpretation of thematic cartography and the application of sophisticated methods like remote sensing and laboratory automated image analyses combined with field transects, provided a unique set of tools for generating and synthesizing data. These data were invaluable in order to obtain the spatial predictions about soil and paleosequence distribution.

Our research results reveal that: (a) in the study area there are seven different soil groups, 19 subgroups, one group of relict paleosols, and two genetic types of alterites; (b) the phenomenon of topography-induced environmental differences, and the slope-profile position commonly have a notable influence on the spatial distribution and variability of soil groups; (c) all studied paleosols meet many of the taxonomic requirements for Luvisols, while some alterites satisfy the diagnostic characteristics of Fragipans or Duripans; (d) the pattern of paleosequence spatial distribution in the Morelos landscapes is closely parallel to the distribution of late Pleistocene–Holocene volcanic geomorphic elements. In addition, many of the studied soils and paleosequences show distinctive spectral properties that allow their accurate identification by means of automated image analyses. These results suggest that the spatial distribution of these soils and paleosequences in Morelos state are geographically predictable.