Nateq Lashkari Sanami; Jamshid Ghorbani; Seyed Mohammad Hodjati; Ghorban Vahabzadeh Kebria; Babak Motesharezadeh
Abstract
Introduction: Mining activities causes substantial damage to the environment worldwide. Abandoned mine wastes from mining activities limit the growth of plants due to unfavorable conditions and the concentration of a wide range of heavy metals. Identifying plant species growing on mine waste and assessing ...
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Introduction: Mining activities causes substantial damage to the environment worldwide. Abandoned mine wastes from mining activities limit the growth of plants due to unfavorable conditions and the concentration of a wide range of heavy metals. Identifying plant species growing on mine waste and assessing their seed germinations are important for vegetation restoration on mining areas. This study aimed at assessing the germination characteristics of Artemisia absinthium, Lepidium draba, and Silybum marianum naturally growing on coal mine wastes in Mazandaran Province under different concentrations of copper (Cu), lead (Pb), and cadmium (Cd).Material and methods: Seeds were collected from plants growing in coal wastes during 2 years. Completely randomized design was conducted with three replicates. Treatments were CuSO4 and Pb(NO3)2 at 0 (control), 50, 100, 200, and 300 mg/L, and Cd(NO3)2 at 0 (control), 5, 10, 20, and 30 mg/L. In each replicate 20 seeds were placed in a Petri dish containing a layer of filter paper. Then treatments were applied and Petri dishes were taken to a germinator under controlled temperature, moisture, and light. Germinated seeds were counted daily and then germination percentage, germination rate, allometric coefficient, seed vigor index, phytotoxicity percentage and seed tolerance index were calculated.Results and discussion: The results showed that increasing the concentration of lead, copper, and cadmium significantly affected the seed germination of studied plants. S. marianum had better germination percentage and rate in lead, and copper while germination of A. absinthium, L. draba, was better in cadmium, and copper, respectively. The greatest reduction in germination percentage was found for A. absinthium in 20 and 30 mg/L Cd. As the concentration of metals increased, significant reduction in germination percentage and rate for A. absinthium started in lower concentrations than other species. Root and shoot length of all species was significantly reduced even in low concentration of metals and S. marianum had greater root and shoot length under all treatments. Reduction in seed vigor index was greater under Cu than that in Pb and Cd. High tolerance index was found for L. draba in response to Cd and for S. marianum under the stress of Pb and Cu. In all treatments, an increase in metal concentration significantly increased the phytotoxicity index. Under Cu and Pb S. marianum showed the least phytotoxicity index, while the lowest phytotoxicity index was found for L. draba under Cd stress. Cu and Cd in high concentration were more toxic for A. absinthium than that for the other two species. Under similar concentrations of Cu and Pb, all species showed reduced germination in copper stress. Cd in lower concentrations were tolerable for plants but generally it had the greatest inhibition especially on A. absinthium.Conclusion: Overall the responses were different regarding the plant species, metal and concentrations. All three species were able to germinate at high concentrations of heavy metals. The presence of these species in coal wastes and their ability to germinate in high concentrations of heavy metals makes it possible to use these plants in future restoration and phytoremediation programs.
Lale Amozgar; Jamshid Ghorbani,; Maryam Shokri; Seyed Hassan Zali
Volume 12, Issue 4 , January 2015
Abstract
Environmental factors particularly soil properties influence the species composition and vegetation diversity in rangelands. Soil in some parts of lowland areain Mazandaran province is saline. This made some limitations for establishment of vegetation. In this study the relationship between vegetation ...
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Environmental factors particularly soil properties influence the species composition and vegetation diversity in rangelands. Soil in some parts of lowland areain Mazandaran province is saline. This made some limitations for establishment of vegetation. In this study the relationship between vegetation and soil properties were assessed in lowland rangeland of Hyrcanian zone in the city of Behshahr, Mazandaran Province. Vegetation was sampled along transects with 100 m length using 1 m2plots. Cluster analysis showed six vegetation types. ANOVA results indicated that greater values of species richness and diversity indices were found in Artemisia sieberi-Medicago rigidulaand Halocnemum strobilaceum-Juncus maritimus. Results from RDA analysis showed that salinity, soil texture and soil moisture are main drivers of vegetation distribution in this area. An increase in EC,CaCo3andsilt was associated with the establishment of Salicornia europaea-Spergularia marinaand Halocnemum strobilaceum-Juncus maritimus. Aeluropus littoralisand Hordeum marinum-Plantago psylliumwere found where soil had lower EC but higher moisture, Organic carbon and clay. A reduction in soil EC and soil moisture was the favorite of Artemisia sieberi-Medicagorigidulaand Juncus maritimus.
