Evolution of arsenic, lead, iron and manganese in evergreen trees affected by the Aznalcóllar mine spill

8 páginas, 4 tablas, 2 figuras, 10 referencias.-- Pertenece al Capítulo I: Terrestrial Ecosystem.-- Dr.Paula Madejón presented her Doctoral Thesis on March 2004 about the bioaccumulation of trace elements in plants affected by the Aznalcóllar mine spill, currently she is working as a postdoc student at The John Moores University in Liverpool; Dr. Teodoro Marañón is research scientist in the CSIC, with experience in plant ecology; Dr. José Manuel Murillo is research scientist in the CSIC with experience in plant nutrition and plant-environment relationships, he is the research leader of the project supporting this study; Dr. Francisco Cabrera is research scientist in the CSIC, with a long experience in the chemical environment of the Guadiamar river.

Bioaccumulation of As and Pb (toxic elements), and Fe and Mn (micronutrients) have been determined in leaves and fruits of two evergreen tree species (Olea europaea and Quercus rotundifolia) in a "dehesa" woodland affected by the Aznalcóllar mine spill, which occurred on the 25 April 1998. Comparing with adjacent non-flooded woodland we have found higher level of As in Olea leaves and fruits, and of Fe in Quercus leaves (but lower Mn level). Quercus leaves accumulated higher content of As, Pb, Fe and Mn than Olea leaves, partly due to a possible external deposition. Fleshy drupes of wild Olea (important component of the diet of many birds) showed toxic levels of As (up to 18 mg kg-1) and Pb (up to 35 mg kg-1) in 1999 but decreased in 2000. A monitoring of trace element concentration in leaves and fruits of polluted trees is recommended.

This study was carried out under the framework of the Programa de Investigación del Corredor Verde (PICOVER), supported by the Andalusian regional government (Consejería de Medio Ambiente, Junta de Andalucía), Spain. We thank Juan Marañón, Lola Hurtado and José María Alegre for their help in sampling. As and Pb concentration in plants were determined (by ICP-MS) in the Centre for Scientific Instrumentation, University of Granada.

Peer reviewed