Eisa Solgi, Faezeh Yar Ahmadi,
Volume 13, Issue 2 (9-2015)
Abstract
Background and Aim : Contamination of the surface soils of the urban ecosystem with heavy metals poses potential ecological risks. In this research, a preliminary investigation was carried out to evaluate the potential ecological risk of cadmium and lead contamination in urban park soils in Assadabed City, Iran.
Materials and Methods : Soil samples were taken from the urban parks of Asadabad city and analyzed for heavy metals using atomic absorption spectrometry. Based on the concentrations of Cd and Pb in the soils, contamination factor (CF), contamination degree (Cdeg) and potential ecological risks status (RI) of the soils were calculated.
Results : Preliminary results showed a low degree of contamination of urban parks of of Asadabad City. Assessment of the potential ecological risk index (RI) indicated that the cumulative heavy metal contents of the soil do not pose any significant ecological risks. In any case, further analysis of the data showed that the potential ecological risk posed by cadmium was higher than that by lead.
Conclusion : The findings indicate that although urban park soils may be polluted due to presence of certain heavy metals, on the whole their ecological risk is insignificant. These findings can help greatly environmental managers in planning, risk assessment and decision-making in the area.
Eisa Solgi, Raziyeh Yazdanyar , Mina Taghizadeh,
Volume 17, Issue 4 (3-2020)
Abstract
Background and Aim: Phytoremediation is a promising method for improving soils that can easily absorb heavy metals, resulting in decontamination of the soil. The objective of this study was to assess the phytoremediation potential of Alyssum maritimum in the remediation of lead-contaminated soil.
Materials and Methods: A randomized complete block design was used with five levels of lead (Pb) concentration (as lead nitrate) and Alyssum maritimum with six treatments in the research greenhouse of Malayer University, Malayer, Iran. After growth and flowering of the plant, lead concentration in its different organs was measured by atomic absorption spectrometry. The bioaccumulation factor (BCF) and the translocation factor (TF) were used to determine the potential of plant species selected for removing heavy metals from the soil in the environment.
Results: Analysis of the data showed that the highest accumulation of lead nitrate was in the leaf. It could be expected, then, that an increase in the concentration of Pb in the soil would result in the accumulation of Pb in the organs of Alyssum maritimum. Generally the degree of Pb accumulation in various plant organs followed the pattern: leaf > root > stem pattern. The BCF and TF indices of Alyssum maritimum species were greater than 1, which would indicate a high potential for transfer and accumulation of lead in the above-ground parts of the plant.
Conclusion: The selected plant species has, based on defined criteria for a heavy metal hyperaccumulator plant and its bioaccumulation factor and translocation factor values, a high potential for remediation of lead-contaminated soil and can be included in the group of hyperaccumulator plants.
Eisa Solgi, Arezoo Soleimany, Vida Hatami,
Volume 21, Issue 2 (9-2023)
Abstract
Background and Aim: Air pollution is currently one of the most important environmental issues. The most common effect of air pollution on plants is the gradual decomposition of chlorophyll and leaf yellowing, which may result in the reduction of photosynthetic capacity. This study aimed to investigate the effect of air pollution on the chlorophyll content and zonation of leaf chlorophyll content of two tree species in Malayer city, Iran.
Materials and Methods: Samples were collected from two tree species, namely, Platanus orientalis and Robinia pseudoacacia in different parts of Malayer city, Iran (clean and polluted areas), each with three replications. The concentration of pigments in the leaves was measured by the Lichtenthaler (1987) method, which is the modified Arnon method (1949), at 663 and 645 nm wavelengths, absorbance being measured using a spectrophotometer.
Results: Data analysis showed that the a, b and total chlorophyll contents in the acacia tree species in the southern parts (southwest) of the study area reached their maximums, while their contents were lowest in the eastern and north-western parts and low to medium in the central parts of the study area. On the other hand, as regards the sycamore species, in the eastern and north-western parts of the study area the a, b, and total chlorophyll contents were the highest and reached their minimums in the south-western parts. However, as in the case of the acacia species, in the central parts of the study area the contents of the tree chlorophylls were low to medium.
Conclusion: The results of this study show that the a, b and total leaf chlorophyll contents of the two acacia and plantain species were higher in the polluted areas as compared to those in clean areas. On this basis, it can be said that a higher physiological index, such as an increased chlorophyll content, indicates the plant's response for resistance to air pollutants.
