The Anthropic Impact on the Development of the Soil the Former Texcoco

Abstract

Lake Texcoco has been drained and impacted by human activities for over 100 years through the construction of drainage canals and more recently through the construction of an airport project. This caused not only the drying up of the lake, but also the drastic loss of moisture from the lacustrine sediments, so it is unknown if soils are forming. The objectives of the present research are to analyze the morphological characteristics and the chemical and physical properties of the lake sediments/soil of the former Lake Texcoco, to determine the formation of the soil and the natural or anthropogenic factors that have the greatest influence on its development, as well as to know its spatial distribution and the depth at which it is found. The information was generated from a 1:20,000 scale soil study on 18,000 ha of the Lago de Texcoco Federal Zone (CONACYT-COLPOS, 2021). Forty-four soil series were delineated and morphological, physical, and chemical data were collected for each series, which were used to create thematic maps. The salinity of the lake, its artificial (differential) drying, and the introduction of halophytic grasses have favored the formation of soils from lake sediments. They mainly modified the development of prismatic and block structures, the movement of clay and sand particles, and the occurrence of redox conditions. All this indicates a diverse morphology for a relatively small area and the presence of soil formation processes. The edaphic properties show a very heterogeneous spatial and vertical distribution within the soil profile, indicating that the soils of Lake Texcoco are in the early stages of development. However, it is not possible to determine at what depth their formation occurs.