Authors: Hector Estrada-Medina, Patricia Montanez-Escalante
, Luis E. Trejo-Salazar
, Roberto
Barrientos-Medina
, Mariana Lopez-Diaz
, Oscar Alvarez-Rivera |
Abstract: Discharge of detergent-containing wastewater (greywater) into soils is common in rural areas in
Yucatan, Mexico since the majority of soils are shallow and bedrock makes the building of
drainage systems a challenge. The aim of this study was to evaluate the effect of greywater
discharges on shallow soil properties. Physical and chemical properties of soil samples collected
from 100 household home gardens in the municipality of Hunucma, Yucatan were analysed.
Two soil samples were taken in each home garden, one in a soil affected by greywater discharges
and one in unaffected soil. Average powdered detergent used was 7 kg / year / home garden. Our
calculations indicated that 23 tons of sodium and 19 tons of phosphorus are verted annually in
the Hunucma municipality. Compared to unaffected soils, samples of greywater-affected soils
contained significantly higher pH and electrical conductivity values and higher phosphorous and
sodium contents, as well as lower REDOX potential and sand and silt contents. Greywater
discharges modify the physical and chemical properties of shallow soils. Further research is
needed to better understand the dynamics of the elements contained in the detergent-containing
greywaters, systematically verted on soils, as well as their impacts on vegetation development
and aquifer contamination. |