Programa e Resumos - I Congresso Ibérico de Ciência do Solo 2004

I Congresso Ibérico da Ciência do Solo – 15 a 18 de Junho de 2004, Bragança, Portugal
Effects of Zn on Bromus rubens L. in a Polluted Calcic Luvisol Soil.
Potential Use of the Species in Revegetation and Phytoremediation.
Ana J. Hernández Sánchez 1 & Jesús Pastor Piñeiro 2
1 Departamento Interuniversitario de Ecología, Universidad de Alcalá, Alcalá de Henares
(Madrid). E-mail: anaj.hernández@uah.es
2 Departamento de Biología Ambiental. Centro de Ciencias Medioambientales, CSIC, Madrid.
E-mail: jpastor@ccma.csic.es
Abstract
Comunicação: Painel
The most heavily metal polluted soils in central Spain are found in areas occupied by
abandoned mine lands and old urban and industrial waste landfills. Zn is the most
extensively dispersed pollutant and can reach phytotoxic concentrations.
Although several plant species are known to take up metals from the soil, the different
ability of these species to do so has not yet been established, and because of their
particular ecologic characteristics, many are unable to grow in the conditions of the area
examined in the present study. Unfortunately, there is a lack of relevant data on the
phytoremediation and revegetation potential of native plant species able to grow in
polluted and degraded soils in xeric environments. One such species is Bromus rubens
L., a native plant that grows in xeric grass and shrub lands.
The area under study was previously screened to establish which species grew best by
stratified sampling and performing plant inventories. Soil samples were obtained from
degraded and polluted environments in xeric areas and from reference, neighbouring
herbaceous ecosystems.
Bromus rubens L. was found in 44 sites. Their ecological profile indicated a preference
for the soils of highest Zn levels. When Zn was determined in plants collected from
these soils, Zn levels in the red brome were found to increase as the Zn concentration of
the soil rose.
In a pot experiment on a calcaric luvisol, increasing soil Zn content was observed to
mostly affect the root levels of this metal, but raised contents were also detected in the
aerial part of the plant. Root Mn and Mg were also seen to rise with increasing Zn
levels. In the aerial part of the red brome, soil Zn was associated with increased Cu and
Ca, and lower Mg levels.
Collectively, the results suggest that this species is able to accumulate significant Zn
concentrations. The relatively good size and soil cover achieved by the red brome in
polluted soils, means it could be a suitable candidate for use in studies directed towards
the revegetation and phytoremediation of xeric degraded soils as those examined here.
Acknowledgements: This study was funded by the REN2002-02501/ TECNO project.
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