Potential Cultivation of Hordeum Vulgare L. in Soils With High Mercury Background Concentrations

Abstract

Experimental work was carried out under close-to-real conditions to study mercury uptake by Hordeum vulgare L. cultivated in lysimeter experiments. The soil in the lysimeter experiment was obtained from a test plot located near Almadén (Spain) and had a mean mercury content of 22.9 mg kg⁻¹. A sequence of four crops was sown starting in autumn 2000 and repeated on a yearly basis until 2004. The first crop was grown in the field prior to the extraction of 5 one-cubic-meter lysimeters. The succeeding crops were sown in the lysimeter experiments at the CIEMAT Research Centre (Madrid, Spain). Samples of root and shoot were obtained during the four seasons. Concentrations of mercury at plant maturity in roots vary between 1 and 3 mg kg⁻¹ and in straw and grain the concentrations range from 72 to 480 μg kg⁻¹ and from 5 to 257 μg kg⁻¹, respectively. In order to assess the potential risk for human health and animal feed, an evaluation of the mercury content in the edible part of the crop has been carried out. According to legislation, there is no human health intoxication risk with a balanced consumption; otherwise, the forage use would have to be controlled.

KEY WORDS::

• Hg
• Hordeum vulgare L.
• lysimeter
• Almadén
• land use

ACKNOWLEDGMENTS

The authors are grateful to Minas de Almadén y Arranyanes (MAYASA), S.A for their collaboration and support during the work. Thanks also go to the kind collaboration of Ms. M. Villadóniga.

This work was financed and supported by the R&D Programme of the Spanish Ministry of Science and Innovation and included within the RETAMA project (Ref: REN 2002-04229-CO2/TECNO) and REUSA project (Ref: CTM 2005-04809-CO2/TECNO).