Carlos Alberto Ortiz Solorio

Heavy metals contamination in soils around tailing heaps with various degrees of weathering in Zimapán, Mexico

Dispersion of mine tailings is the main cause of heavy metal (HM) contamination in soils in Zimapán, Mexico; however, the extent of this problem has not been assessed. Therefore, the aims of this study were to determine the degree of contamination and to assess the influence of mine tailings with different degrees of weathering on the spatial distribution of HM in soils. Soil and mine tailing sampling was carried out. The HM concentration was determined by atomic absorption spectrophotometry; spatial analysis and the size of the contaminated areas were calculated using GIS software; the mine tailings were characterized physically, chemically and mineralogically. The results suggest that all the tailing heaps have contributed to the HM dispersion. High HM concentrations were founded in soils around mine tailings (9402 mg kg−1 Pb and 52 mg kg−1 Cd). Surface area contaminated with Pb and Cd was estimated at 6.2 and 2.7 km2, in urban soils, respectively.

Influencia de los factores formadores en las propiedades de los suelos en la Mixteca, Oaxaca, México

The soil-forming process is determined by the interaction of six soil-forming factors: climate, organisms, topography, parent material, time and soil use; the magnitude of all soil properties is determined by the action of these factors. In this work we determined the forming factors that influence the type of soil present in the rancho Dolores watershed in the Mixteca region in the state of Oaxaca, as well as the properties of these soils. An analysis of principal components and an unsupervised classification for the delimitation of soil units were carried out, in which samplings and laboratory analysis of some physical and chemical properties were carried out. The forming factors that explain the variability of the soils of the watershed were slope, topographic position index, parental material and land use. Five soil units were delimited with their spatial distribution in the watershed and associated with their properties of texture, apparent density, field capacity, permanent wilting point, saturation percent, saturated hydraulic conductivity, pH and organic matter content. There is a strong relationship between the relief parameters and the soils, reason why we recommend the study of the formation, distribution, and cartography of soils from a geomorphological point of view, as well as the analysis of vegetation.The soil-forming process is determined by the interaction of six soil-forming factors: climate, organisms, topography, parent material, time and soil use; the magnitude of all soil properties is determined by the action of these factors. In this work we determined the forming factors that influence the type of soil present in the rancho Dolores watershed in the Mixteca region in the state of Oaxaca, as well as the properties of these soils. An analysis of principal components and an unsupervised classification for the delimitation of soil units were carried out, in which samplings and laboratory analysis of some physical and chemical properties were carried out. The forming factors that explain the variability of the soils of the watershed were slope, topographic position index, parental material and land use. Five soil units were delimited with their spatial distribution in the watershed and associated with their properties of texture, apparent density, field capacity, permanent wilting point, saturation percent, saturated hydraulic conductivity, pH and organic matter content. There is a strong relationship between the relief parameters and the soils, reason why we recommend the study of the formation, distribution, and cartography of soils from a geomorphological point of view, as well as the analysis of vegetation.