Introduction

Mesquite (Prosopis laevigata [Humb. et Bonpl. ex Willd.] M.C. Johnst) is a characteristic species of the arid and semi-arid zones of Mexico. It has ecological and economic relevance and has been identified as a plant capable of accumulating lead (Pb) in soils irrigated with wastewater.

Objective

To determine the bioconcentration of Pb in mesquite trees established in soils irrigated with wastewater, to identify their phytoextraction capacity.

Methodology

Seventy-two plant samples (from 24 trees) and 24 soil samples from under the canopy were collected from a 37.3 ha area irrigated with wastewater. Lead concentration was determined in all samples, and bioconcentration and translocation factors were estimated. The results were analyzed using the Kruskal-Wallis and Mann-Whitney tests.

Results

The concentration of extractable Pb in the soil was 1.99 mg∙kg-1, while in roots, leaves, and fruit it reached 79.61, 21.4, and 64.13 mg∙kg-1, respectively, demonstrating the transfer of Pb from the soil to the plant. The Pb concentration in roots and fruit was significantly higher than in leaves. The bioconcentration factor was 102.86, and the translocation factor was 9.52.

Limitations of the study

It is necessary to evaluate the influence of tree age on the processes of Pb accumulation and translocation.

Originality

Trees that grew naturally in soils irrigated with wastewater for 47 years were evaluated.

Conclusion

Mesquite is a species with the capacity to phytoextract Pb in soils irrigated with wastewater.

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