Zeliha Leblebici

Growth and bioaccumulation characteristics of watercress (Nasturtium officinale R. BR.) exposed to cadmium, cobalt and chromium

Abstract The aim of this study is to determine the effects of Cd, Co and Cr on the growth of watercress (Nasturtium officinale) and to determine the bioaccumulation properties of these heavy metals by the plant. N. officinale individuals were exposed to different concentrations of Cd, Co and Cr for 72 h. Relative growth rates (RGR) and bioconcentration factor (BCF) ratios were calculated for each metal concentration. RGR values of plants exposed to Co slightly increased in lower concentrations, but then decreased again. In contrast, RGR values of plants exposed to Cd and Cr decreased linearly. Significant positive relationships were observed among the concentrations of Cd, Co and Cr in N. officinale and in the culture solution. BCF ratios were highest for plants exposed to Co, and lowest for plants exposed to Cr. The most efficient uptake of Cd, Co and Cr occurred at the external solution concentrations at 0.5, 0.5 and 10 mM, respectively.

Verbascum bombyciferum Boiss. (Scrophulariaceae) as possible bio-indicator for the assessment of heavy metals in the environment of Bursa, Turkey.

In this study, we determined the heavy metal content (Cd2+, Cr3+, Cu2+, Fe3+, Ni2+, Pb2+, and Zn2+) in the soil surrounding the roots and different organs of Verbascum bombyciferum Boiss. (Scrophulariaceae), which is endemic to Uludağ Mountain, Bursa, Turkey. Plant samples were collected from roadsides, and heavy metal accumulation capabilities were tested. This is one of the pioneer species of ruderal plant communities on roadsides, building sites, rubbish dumps, etc. Different organs of plant samples (roots, stems, leaves, and flowers) and their soils were analyzed by inductively couple plasma optical emission spectroscopy for their heavy metal contents. Some of the analyzed heavy metals (Cd2+, Cr3+, Pb2+, and Zn2+) were usually increased depending on the traffic in the sample sites, and this variation was also reflected in heavy metal content of plant samples. Our results show that this plant can be used as a bio-indicator species in the monitoring of increased Cd2+, Cr3+, Pb2+, and Zn2+ in the environment. We also concluded that V. bombyciferum have the capability of Cd2+, Cr3+, Cu2+, Ni2+, Pb2+, and Zn2+ accumulation.

Bioaccumulation of Nickel, Copper, and Cadmium by Spirodela polyrhiza and Lemna gibba

ABSTRACT Lemna gibba and Spirodela polyrhiza were exposed to different concentrations of Ni, Cu, and Cd for 10 days. Bioaccumulation of the three metals for both plants were dependent on and positively correlated with the external metal concentrations. Both plants were hyperaccumulators of Cd but not of Ni or Cu. L. gibba was more effective in extracting all three metals than was S. polyrhiza.

Biomonitoring of Heavy Metal Pollution Using Lichen (Pseudevernia furfuracea (L.) Zopf.) Exposed in Bags in a Semi-arid Region, Turkey

In this study, the lichen Pseudevernia furfuracea (L.) Zopf. samples were collected from Cat Forests near the village of Sizir in Sivas province and exposed in bags in 29 different sites of Kayseri city, Turkey. The elements Pb, Cd, Cu, Zn, Cr, and Co were analysed by ICP-OES in the lichen samples. Lichen bags were exposed for two periods (dry and wet) starting from the beginning of July 2005. In the wet period, it was observed that the lichen accumulated a larger quantity of metals. The contents of heavy metals in lichen samples were found to be in range of 0.16–0.31 μg g−1, 9.50–18.89 μg g−1, 23.50–68.24 μg g−1, 3.10–30.81 μg g−1, 0.07–2.54 μg g−1, and 3.33–5.63 μg g−1 for Cd, Cu, Zn, Pb, Cr, and Co, respectively. Pseudevernia furfuracea has been found to be a useful biomonitor of the six heavy metals studied because of greater lichen resistance to the dry and stressing conditions of urban environments.

Determination of Heavy Metal Pollution in Some Honey Samples from Yozgat Province, Turkey

The concentrations of heavy metals (Pb, Cd, Fe, Ni and Zn) in 21 different honey samples collected from 21 different farms in Yozgat, Turkey, were determined by ICP-OES after microwave digestion. It is observed that metal concentrations in honey samples ranged between 0.06 and 0.139 μg g−1 for Cd 0.03 and 1.20 μg g−1, for Zn 0.035 and 1.690 μg g−1, for Pb 0.006 and 2.332 μg g−1 for Ni and 0.703 and 8.150 μg g−1 for Fe. Although, the honey samples were in good quality, they were not free of heavy metals. It is interesting that the stations in which the metal concentration is maximum within the examined honey samples are near the settlement regions where the traffic and industry is especially intensive. According to these results; it is concluded that the heavy metal concentrations in honey samples excluding some stations which are close to the settlement regions are in acceptable borders.

Influence of nutrient addition on growth and accumulation of cadmium and copper in Lemna gibba

Abstract Aquatic plants have been identified as potentially useful for accumulating and bioconcentrating heavy metals. This study was developed to test the hypothesis that nutrient enrichment enhances the metal tolerance of floating macrophytes. Relative growth rates (RGR), photosynthetic pigments (chlorophyll a, b and carotenoid), malondialdehyde (MDA) content, and electrical conductivity (EC) were measured in Lemna gibba exposed to different cadmium and copper concentrations in laboratory conditions. Relative growth rates were negatively correlated with metal exposure, but nutrient addition suppressed this effect. Photosynthetic pigment levels were negatively correlated with metal exposures, and nutrient addition attenuated chlorophyll decrease in response to metal exposures. MDA content and EC also showed sharp increases at higher concentrations, indicating oxidative stress. This study indicates that nutrient enrichment increases the tolerance of Lemna gibba to metals, and that Lemna gibba is a suitable candidate for the phytoremediation of low-level copper and cadmium pollution.