Accumulation of heavy metals and antioxidant responses in Pinus sylvestris L. needles in polluted and non-polluted sites
Ecotoxicology
Accumulation of heavy metals and antioxidant responses in Pinus sylvestris L. needles in polluted and non-polluted sites
Marta Kandziora-Ciupa 0
Ryszard Ciepał 0
Aleksandra Nadgo´ rska-Socha 0
Gabriela Barczyk 0
0 Department of Ecology, University of Silesia , Bankowa 9, 40-007 Katowice , Poland
The purpose of this study was to determine the concentrations of heavy metals (cadmium, iron, manganese, lead and zinc) in current-year, 1-year old and 2-year old needles of Pinus sylvestris L. Trees were from three heavily polluted (immediate vicinity of zinc smelter, iron smelter and power plant) and three relatively clean sites (nature reserve, ecologically clean site and unprotected natural forest community) in southern Poland. Analysis also concerned the antioxidant response and contents of protein, proline, total glutathione, non-protein thiols and activity of guaiacol peroxidase (GPX) in the needles. Generally, in pine needles from the polluted sites, the concentrations of the metals were higher and increased with the age of needles, and in most cases, antioxidant responses also were elevated. The highest levels of Cd, Pb and Zn were found in 2-year old pine needles collected near the polluted zinc smelter (respectively: 6.15, 256.49, 393.5 mg kg-1), Fe in 2-year old pine needles in the vicinity of the iron smelter (206.82 mg kg-1) and Mn in 2-year old needles at the ecologically clean site (180.32 mg kg-1). Positive correlations were found between Fe, Mn and Pb and the content of proteins and NPTs, between Cd and non-protein -SH groups, and between Zn and proline levels. The activity of GPX increased under the influence of Mn, while glutathione levels tended to decrease as Mn levels rose. The data obtained show that the levels of protein and non-protein - SH groups may be useful in biological monitoring, and that
Abbreviations
NPTs Non-protein thiols
GSHt Glutathione total
GPX Guaiacol peroxidase
these ecophysiological parameters seem to be good
evidence of elevated oxidative stress caused by heavy metals.
Antioxidant response
Heavy metal Pinus
Introduction
Atmospheric pollution constitutes a major problem in
urban environments
(Al-Khlaifat and Al-Khashman 2007;
Sawidis et al. 2011; Chen et al. 2016; Zhao et al. 2016)
.
Pollutants containing trace metals are released from many
different anthropogenic sources such as industry, and the
combustion of fossil fuels in vehicles and energy plants
(Sawidis et al. 2011). Heavy metal contamination can be
exceptionally high in the vicinity of smelting operations
and near mine tailings, i.e. materials left over after the
process of separating the valuable fraction from the
uneconomic fraction of an ore
(Probst et al. 2009; Bothe
2011; Nadgo´rska-Socha et al. 2013b)
. The accumulation of
those anthropogenic trace metals in plants has drawn
considerable attention as a possible indicator of inorganic
pollution of the environment, as plants respond directly to
the state of the soil and air
(Divan et al. 2009; Fowler et al.
2009; Serbula et al. 2013)
.
Environmental quality monitoring using biological
material is commonly accepted as a reliable and affordable
way of obtaining information on heavy metal
contamination. The main advantage is the opportunity for long-term
comparisons without the need for expensive equipment
(Massa et al. 2010)
. The higher trophic plants most often
used for biomonitoring in industrial and urban areas are
coniferous and deciduous trees
(Rademacher 2001; Piczak
et al. 2003; Serbula et al. 2013)
. Their one great advantage
is that they are long-lived, so that repeated investigations
are possible over decades. They can thus be sampled
systematically with standardized sampling and analytical
techniques for comparative monitoring of the temporal
distribution of trace elements. Trees are usually easier to
identify than lower trophic plants and can be used as
effective biomonitors to detect even low levels of
anthropogenic pollutants. Although it can be difficult to
distinguish between the amount of pollutants taken up from the
soil to that deposited on the leaves, trees still reflect the
cumulative effects of environmental pollution
(Berlizov
et al. 2007; Sawidis et al. 2011)
.
The Scots pine (Pinus sylvestris L.), the main
forestforming species in Europe, is sensitive to several industrial
pollutants, including heavy metals
(Micieta and Mur´ın
1998; Rautio et al. 1998; Nieminen et al. 2004; Chudzin´ska
et al. 2014)
. Pine needles, with their thick epicuticular wax
layer, are most frequently used for biomonitoring of
airborne pollution due to the possibility of both passive and
active uptake by tissues from the atmosphere
(Mingorance
et al. 2007; Sun et al. 2009, 2010; Kuang et al. 2011;
Serbula et al. 2013)
.
Heavy metal uptake and accumulation by plant tissues
causes various morphological, physiological and
biochemical responses
(Doganlar and Atmaca 2011)
. Some
metal ions are likely to remain in the cytopl (...truncated)