جستجوی مقالات مرتبط با کلیدواژه « گیاه پالایی » در نشریات گروه « محیط زیست »

Mining activities and metal extraction are major factors in soil pollution, and generally surface soils around mines contain high amounts of these metals. The purpose of this research is to investigate the ability of lead absorption by Erodium cicutarium plant from lead contaminated soils. After identifying the collected plant samples, the samples were prepared for relevant analysis. Then, the amount of lead element, electrical conductivity, pH was measured and the ability of plant samples to absorb and accumulate lead was investigated by calculating the bioconcentration factor (BCF) and displacement factor (TF). According to the results, the total amount of lead in the soil ranges from 377 to 1250 mg-1kg of dry weight. Also, it can be seen that the exchangeable amount of lead elements in the soil ranges from 4 to 15 mg-1kg of dry weight. The average pH of the soil samples ranged from 6.8 to 7.1. Also, the results showed that the highest average amount of lead in Erodium cicutarium plant is 1516 mg-1kg in the roots, 110 mg-1kg in the aerial parts and 637 mg-1kg in the soil. Plants with bioconcentration factor (BCF) greater than one and displacement factor (TF) less than one are suitable for plant stabilization. Investigations showed that the bioconcentration factor in Erodium cicutarium plant is 2.3 and the transfer factor is 0.2. Therefore, according to the results, the plant shows BCF more than one and TF less than one. Therefore, Erodium cicutarium plant is a suitable species for phytoremediation in the form of plant stabilization of lead.

Nowadays, heavy metal pollution has become a serious environmental problem. To protect the environment, one of the effective and low-cost methods is phytoremediation. Phytoremediation is the use of plants to remove, reduce and stabilize pollutants. In this regard, the use of fungi that symbiosis with plants, can increase the efficiency of phytoremediation, reduce the time required to remove contamination, and develop its application.

This experiment was performed in order to investigate the traffic and symbiosis interaction’s effects on lead and cadmium accumulation in rosemary (Rosmarinus officinalis L.). The experiment donen in a randomized complete block design (RCBD) with three replications and three factors as factorial. The first factor includes mycorrhiza symbiosis (control and inoculation), the second factor was traffic (Control, 120, 300, 600, 950, 1200, 1800, 2400, 3000, 3600, and 4200 cars per hour) and the third factor was the type of pot (Controls and pots where the soil surface is covered except at the place of seedlings) with three replications in 2019-2020 in Shiraz metropolis. In the experiment some properties were investigated such as root weight, soil cadmium, shoot cadmium, root cadmium, stem length, main root length, plant dry weight, root lead, cadmium, and lead transfer factors.

The results of mean comparisons showed that inoculation of plants with mycorrhizal fungi )Glomus mossea (had higher lead content of root tissue than shoots and soil in 4200 cars per hour compared to the control. Symbiosis with mycorrhiza fungi increased root weight and plant dry weight, stem length, and main root length compared to the control by 23.93, 18.97, 0.82 and 30.87% in 4200 car traffic per hour, respectively. The results also showed that the treatment of closed pots and inoculation of mycorrhizal fungi increased the growth parameters and decreased cadmium and lead.

The reduction of cadmium and lead concentrations in the inoculated rosemary with Glomus mosses indicates that Rosmarinus officinalis L. can grow in soils contaminated with cadmium and lead. Also, the symbiosis of mycorrhizae increases th ability of rosemary.

Production of clean energy and elimination of waste is one of the priorities of environmentally friendly societies. By producing biogas from manure, biological pollution in the environment can be reduced and energy can be produced. Phytoremediation is one of the ways to remove soil pollutant. The purpose of this research is to investigate the production of biogas from camel dung and phytoremediation waste and also to identify the variables that improve biogas production using the fuzzy AHP method.

The loading of camel dung in the digester has been done at different mesophilic and thermophilic temperatures (36-37 and 55). The waste from the lead phytoremediation was mixed with camel dung and was loaded in similar conditions. During 1 month of material loading, biogas production was measured. The results have been analyzed using SPSS software.

The results showed that pH plays an important role in biogas production. The first load was low due to low input feed as well as failing to reach the desired digestion operation, resulting in very low digestive pH, which gradually increased as the number of gas production speeds and gas production increased. It was also found to decrease the amount of biogas production as the amount of refined plant was increased. The parameters were ranked using the fuzzy AHP method.

According to the results, camel dung has a good potential for biogas production. Nitrogen and phosphorus are more important in biogas production and the ratio of volatile solids has the lowest rank according to the fuzzy AHP method. Phytoremediation waste could be used in small amounts.

Soils and waters are frequently subject to contamination by inorganic elements including As, Cd, Cr, Cu, Hg, Mn, Ni, Pb, and Zn, mainly due to anthropogenic activities, such as mining, incineration of wastes, drilling of petroleum shaft and agricultural practices (i.e., pesticides and sewage sludge application). Phytoremediation employs the use of plants to degrade, remediate and stabilize various environmental contaminants in soil, water and air. Biochar (BC) can be produced from a wide range of organic wastes via pyrolysis. It has great potential as an amendment for phytoremediation but its effects depend on the type of feedstock it derives from. This study was conducted to identify the effects of biochar addition and phytoremediation on As, Cr, and Pb concentrations in a soils polluted by oil drilling wastes.

The current study was carried out to examine the heavy metal immobilizing effect of biochar produced from sugar cane waste and subsequent heavy metal uptake by Sorghum, Atriplex sp. and prosopis farcta. Sugar cane wastage biochar was incorporated into four application rates (0, 0.5, 1 and 2 % (w/w)) and soil biochar mixtures were examined for an incubation period of 2 months (so that the contaminated material could be distributed evenly in the soil particles). Then pot trials were provided for cultivation of Sorghum, Atriplex sp and Prosopis farcta so that for each plant, a row of 12 pots and a total of 36 pots for the three under-study plants.

The results showed, average of Cr, As and pb concentration   in contaminated soil is 56, 53.4 and 582 ppm. Average of Cr, As and pb concentration   in contaminated soil is Amendment with BC is 30, 21.5 and 224. Average of Cr, As and pb concentration   in contaminated soil is Amendment with Sorghum is 22, 7.2 and 43, Amendment with Atriplex sp is 16, 15.3 and 141, Amendment with prosopis farcta is 18, 19.9 and 192 ppm.

Effective treatment of Cr was prosopis farcta and 1 % (w/w) biochar, Sorghum and 2 % (w/w) biochar for As and pb. Although heavy metal-contaminated soils can be reclaimed effectively by application of biochar, further research is needed to explore its long-term environmental and economic aspect to gain maximum benefits from this novel material

The oil industry is an important, job-creating, and feeder industry whose products are used as raw materials for other industries. One of the important environmental problems related to this industry is that oil can leak into the environment during extraction, transfer, refining, and processing. Environmental oil pollution poses a major threat to the ecosystem and human health. Therefore, the elimination of oil contaminants entering the environment, especially soil, is essential for environmental health. The current study aims to provide general information about phytoremediation and review the latest research on the use of different plants to remove oil pollutants from the environment. Additionally, several plant species with the ability to remove oil pollutants have been introduced.

To conduct this study, the electronic libraries of Elsevier, Springer, and Science Information Center (SID) were searched using the keywords Phytoremediation, Oil Contamination, Plant Remediation, Oil Pollution, and Oil Pollutant. The sources were analyzed after extraction and subject classification.

By exploring the sources of scientific information, 10 review articles were extracted as the core and a total of 99 references were extracted and analyzed. Based on the findings, the use of plants to remove all kinds of pollutants has been introduced as one of the cost-effective and environmentally friendly methods. Among the advantages of phytoremediation, the following were mentioned: The need for small financial investment, the possibility of removing pollutants on site, proper aesthetics, preventing soil erosion, preventing the release of toxic substances, and the possibility of using this method in areas with low pollutant concentrations. According to studies, plants utilize various mechanisms, including phytoextraction, phytovolatilization, phytostabilization, phytodegradation, rhizodegradation, or rhizofiltration to remove pollutants from environments. In this study, 12 plants effective in removing heavy metals and 30 plants capable of phytoremediation of oil and related toxic compounds, i.e. polycyclic aromatic hydrocarbons, were introduced. 

Phytoremediation is an environmentally friendly method that is based on solar energy. It is economically reasonable and its commercialization is possible. Currently, phytoremediation technology is in its early stages and there are many technical problems to be overcome for its development. Among plants, herbaceous plants because of their high root surface area are efficient in the removal of polycyclic aromatic hydrocarbons. Currently, especially in our country, there is an urgent need to discover new plant species with the ability to tolerate and remove environmental pollutants such as oil pollution. It is also necessary to carry out research to optimize plant treatment processes, understand plant–environment interactions, and microbial interactions and finding appropriate equipment to do it. In addition, the use of molecular techniques and the development of transgenic plants to increase the efficiency of the plant to remove toxic materials are expanding. Therefore, genetic engineering is expected to play an important role in increasing the application of plant breeding technologies. Studies on these strategies will be very useful in developing simpler and cost-effective tools for phytoremediation.

Industrialization can be one of the main causes of environmental pollution increasing, especially petroleum hydrocarbons in the water, air, and soil. Polluted soils in the evaporation ponds are one of the primary sources of pollution in the oil refineries. Phytoremediation is the use of plants to remove contaminants from contaminated soils, to accumulate them in the roots and to remove them from the stems and leaves, or to decompose these compounds within the plant. Choosing the right plant, especially in soils with low or moderate pollution, plays an important role in the process of phytoremediation. Vetiver is a suitable plant for phytoremediation. In this project, first, soil samples were collected and the survival and resistance of vetiver were investigated. After that, executive works started in the Dalan area, including planting plants in the area, installing a reservoir, installing a drip irrigation system, sampling contaminated and non-contaminated soils in the area, and sampling the soil adjacent to the plant roots and measuring the amount of Petroleum hydrocarbons. The vetiver plant can grow and survive in oil-polluted soils. After a year of phytoremediation effect, the Vetiver plant reduced the amount of total petroleum hydrocarbons and aromatic hydrocarbons by about six times and nine times, respectively. Further phytoremediation treatment with vetiver root (soil rhizosphere near the root) could further reduce the amount of total petroleum hydrocarbons and aromatic hydrocarbons.

The issue of soil contamination by waste chemicals has raised concerns about the environment. Among them, heavy metals are also known to be important in low concentrations due to their non-degradability and physiological effects on living organisms. In addition to natural processes, heavy metals can be used by human resources such as mining activities, landfilling of various wastes and wastes, use of sewage sludge in agricultural lands, waste leachate, excessive use of chemical fertilizers, fossil fuels and the like cause soil pollution. Heavy metals do not decompose in the environment, so they need to be removed from the environment. On the other hand, the exorbitant costs of physical and chemical methods have led to efforts to achieve cheaper methods. The use of conventional physical and chemical treatment methods is not economical and cost-effective in cases where the concentration of heavy metals is low, and may even lead to the production of secondary effluents, which in turn will lead to more treatment problems. Therefore, researchers have developed a new method using the potential of plants to eliminate soil pollution and preserve this national capital. Some plants, by developing special mechanisms, can accumulate heavy metals in high concentrations, which are called hyperaccumulation plants. The most characteristic disadvantages of this method are limited to sites with medium and low pollution, low biomass production, shallow roots, low biological access of metals in the soil, especially calcareous and young soils in arid and semi-arid regions, time consuming. These unavoidable constraints are forcing researchers to refine traditional approaches and apply new phytoremediation techniques to minimize the constraints and ensure widespread use of phytoremediation.Selecting suitable species for phytoremediation of heavy metals is one of the critical stages of phytoremediation. Another solution to overcome the problems mentioned in phytoremediation is to use heavy metal-resistant bacteria and plant growth stimulants to strengthen the root system, produce more biomass and increase the bioavailability of metals by plants. Therefore, the use of microbial inoculation will help plant species to effectively filter heavy metals from the soil.The application of phytoremediation technique has been less in our country so far and only in laboratories and experimentally and due to the ignorance and negligence of officials has never been used as an effective method in refining heavy metals in contaminated soils. Therefore, it is necessary to introduce and replace plants and apply new strategies based on the study of cooperation between plants - microbial communities, to be able to expand and localize modern phytoremediation, to reduce soil health risk and increase food security effectively and economically.To achieve the above goals, the following suggestions can be considered:1- Introducing suitable crops to replace cultivation in soils contaminated with heavy metals: Contamination of agricultural lands with heavy elements is a serious risk for the production of healthy crops in Iran and the world. Therefore, it is necessary to reduce the contaminants in the soil by accumulating them in the roots of plants or depositing them in the root zone and transferring them to the food chain by using the bio-stabilization technique. Unlike other phytoremediation techniques, plant stabilization does not remove metal from the soil, but by stabilizing them by adsorption or deposition in the root zone, it reduces their risks to human health and the environment. Plants with high bio-concentration factor (BCF, the ratio of metal concentration in the root of the plant to its concentration in the soil) and low transfer factor (TF ratio of metal concentration in the stem to its concentration in the root) are suitable for plant stabilization. The absence of high concentrations of metals in the stem eliminates the need to discard harvested plants. In this project, sorghum, millet and flax species are proposed for cultivation in agricultural lands to reduce the burden of contamination in crops and food health for study.2- Introduction of herbaceous plants (forage) for stabilization of heavy metals in contaminated soilsConsumption of infected forage plants by livestock and domestic animals can be examined from two perspectives. First, the use of contaminated forage causes disturbances in livestock and domestic animals, such as reduced milk production and growth rate, reduced resistance to binaries and infections, and impaired reproduction. Second, by consuming animal products, pollutants will enter the human food cycle. Also, due to the multiplicity of pollution industries and ways of its transmission, currently the best way to reduce these risks is to take seriously how to feed and control the diet of livestock. Therefore, the use of specific plant species to immobilize contaminants in the soil, through surface adsorption and accumulation by the root, intra-root adsorption or deposition in the root zone and physical stabilization of soils or in other words plant stabilization is also necessary. Plant stabilization reduces the mobility of pollutants and prevents their transfer to groundwater and the atmosphere. Therefore, in this study, several types of forage plants that have economic aspects and good yield, including sainfoin (Onobrychis aucheri Boiss), Timothy (Phleum pratense), Lolium perenne, Lemon Grass Tall fescue, Dactylis glomerata, Agropyron desertorum, Agropyron desertorum in order to produce healthy forage and restore vegetation in pastures and animal health are recommended for research.3- Introducing ornamental overgrowth plants for refining soils contaminated with heavy metalsIn recent years, plant-based environmental treatment technology, or phytoremediation, has been widely pursued as an in-situ cost-effective strategy to clean metals from contaminated sites. In this project, plant extraction means using polluting plants to remove metals or organic pollutants from the soil by accumulating them in harvestable areas. Plant extraction involves planting the plant several times in contaminated soil to bring the metal concentration to an acceptable level. The following species are recommended for review: Parsley (Tagetes patula / erecta), Margaret (Chrysantemum maximum) Marigold (Calendula officinalis / alata), Chrysanthemum (Chrysanthemum indicum), Gladiolus grandiflorus, Pelargonium graveos ).4- Investigation of bacteria resistant to heavy metals with plant growth stimulant properties with the aim of increasing the growth and production of plant biomass under conditions of metal stressUsing bacteria can be a simple and effective strategy to increase growth as well as bioremediation activity. Bacteria have different mechanisms for decontamination of contaminated environments through biosorption, bioaccumulation, sales, bio-mineralization and biotransformation. On the other hand, plant growth-promoting bacteria typically improve plant growth under stress. Some rhizosphere bacteria that directly and indirectly have beneficial effects on plants are called growth-promoting rhizosphere bacteria. These beneficial bacteria (PGPR) are also called product-enhancing bacteria. Growth-promoting rhizosphere bacteria can play a direct role in increasing plant growth and yield by using various mechanisms. Increased dissolution of insoluble nutrients such as phosphorus, production of ACC-deaminase, production of plant growth hormones such as auxin, nitrogen fixation and production of siderophore (from the point of view of increasing iron absorption) are the most important direct mechanisms. Indirectly, growth-promoting rhizosphere bacteria neutralize or modify the harmful effects of plant pathogens by using various antagonistic mechanisms, thereby increasing plant growth. Competition to absorb substances and occupy suitable sites for the activity of pathogens, production of antibiotics, production of siderophores (from the perspective of removing elements from the pathogens), lytic enzymes and production of hydrogen cyanide are the most important mechanisms used in this method.5- Study of bacteria capable of producing chelating compounds with the aim of increasing the efficiency of plant extraction by increasing the dissolution and absorption of metalsThe efficiency of plant extraction of metals from soils depends on the availability of metals to plants. The magnitude distribution of metals and the intensity of their bonding in the soil are influenced by metal species, age and soil properties. If the availability of metals for plant uptake is low, microorganisms can add chelating or acidifying agents to increase the availability of metals to the soil.6- Feasibility study of using bacteria to reduce the accumulation of heavy metals in crops grown in soils contaminated with heavy metals with the aim of reducing health risk and increasing food qualityRhizospheric and endophytic bacteria (with greater potency) in addition to modulating the harmful effects of biological and non-biological stresses (due to heavy metals, salinity, etc.) to the plant can reduce the absorption and accumulation of metals through various mechanisms They are also heavy in the plant (or in the aerial parts). In addition to reducing the destructive effects of heavy metal stresses on plants, heavy metal-resistant bacteria can reduce the availability of heavy metals to plants through various mechanisms in the soil. One of these mechanisms is the adsorption or bioaccumulation of heavy metals inside bacterial cells. At present, heavy metal bioabsorption techniques are recommended for the removal of heavy metals because they are more efficient, less costly, and more environmentally friendly. Root endophytic bacteria prevent their transfer to plant shoots (organs that can be harvested by humans or animals) by adsorption of heavy metals (adsorption of heavy metals on the bacterial cell wall), accumulation, complex formation, reduction and oxidation, etc. Finally, with this method in agricultural lands, the risks of these elements for human and animal health can be reduced.

Landfill leachate contains heavy metals that cause toxic effects on water and soil near landfills. Phytoremediation is one of the control methods in which native plants with accumulation ability are used. The aim of this study was to evaluate the accumulation strength of heavy metals by nettle from leachate.

In the present study, after collecting nettle seeds from Tonekabon landfill, they were planted in 16 pots and after the 6-leaf stage, placed under four concentrations of fresh leachate (0, 30, 60 and 100%) and after the growth period, the amount of metals Heavy (by atomic absorption spectrometer) and morphological traits were measured.

The result showed that with increasing leachate concentration, the amount of heavy metals in all organs increased (Ni> Pb > Cd> Ar) and the aerial parts were more absorbed. In parallel with this result, dry weight factors of stem and leaf, root and leaf area index also decreased. Calculation of TF> 1 in nettle organs showed its ability to be more accumulative in the face of leachate.

Bioremediation with using of native plants and accumulators to remove heavy metals is a low cost and environmentally friendly method. Nettle is a native and wild plant that grows in landfills in the north of the country and due to its accumulative power, it is a suitable species for clearing the soil of heavy metals.

Today, with the increase in world population and the subsequent development of industries and factories, the amount of effluents entering the environment, which often contain heavy metals and various other pollutants, is increasing. Heavy metals have devastating effects on plant and animal health in various ecosystems. In the process of environmental purification, plants are able to absorb heavy metals and can absorb these pollutants from soil and water and store them in their roots and shoots.

In this regard, in order to investigate the uptake and accumulation of heavy metals by plants, an experiment was conducted in a completely randomized design with three replications using vetiver plant. Plants treated with industrial effluent and control plants were irrigated with municipal water. Also, pots containing soil without plants were considered to measure the amount of elements in the soil during the six-month experiment period, they were regularly irrigated with other pots with industrial effluent. In order to investigate the effect of irrigation with effluent on the yield of vetiver plant, after a six-month period of experiment, heavy element analysis and anatomical and physiological studies were performed on plants treated with industrial effluent and control plants. Transfer and accumulation factors, which are two important factors in measuring plant ability for phytoremediation, were also examined.

The results of this study showed that among the most heavy metals in industrial effluents, which included zinc and chromium, most of the mentioned elements were stored in the roots of vetiver and less were collected in the aerial parts. Also, the results of physiological traits experiments showed that the factors of soluble sugars and proline in the treated plants increased compared to the control and the concentration of malondialdehyde in the treated plants decreased compared to the control. The results of root studies in control and treated plants showed that root diameter, central cylinder diameter and number of vascular clusters in treated plants increased compared to control.

Overall, the results of this study showed that in the process of absorption of heavy metals, changes were made in some anatomical and physiological traits of treated plants. Examination of transfer and bioaccumulation factors also showed that vetiver has the ability to absorb zinc and chromium through plant stabilization.

Various methods are suggested for the removal and detection of heavy metals in the environment, most of which require a lot of time and money. Therefore, phytoremediation is a method that requires less time and money than other methods to remove heavy metals from the environment. In the present study, the image processing technique by smart mobile phone was used to determine the contamination of pennyroyal hyper accumulator plants by three heavy metals lead, nickel, and cadmium. Thirty plants were planted in thirty pots in perlite. For 28 days, these plants were photographed by mobile phones, both inside the box and contact imaging. Matlab R2017b software environment was used for image processing and artificial neural network operations. To determine the structure of artificial neural network, 12 neurons (Includes red, green and blue of RGB color space, hue, saturation and brightness of HSB color space, luminosity, blue Chroma and red Chroma of YCbCr color space and bright, red/green and bright yellow/blue L*a*b* color space) neurons as input layer and 4 neurons for output layer once (includes lead, nickel, cadmium, and control) again 2 neurons (containing heavy metal and control) in the output layer, both box and contact images were considered and the best network structure was identified.

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).

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.

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 the other species. Root and shoot length of all species 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 cadmium and for S. marianum under the stress of lead and copper. In all treatments increase in metal concentration significantly increased phytotoxicity index. Under Cu and Pb S. marianum showed least phytotoxicity index while the lowest phytotoxicity index was found for L. draba under Cd stress. Copper and cadmium in high concentration were more toxic for A. absinthium than that for the other two species. Under similar concentrations of copper and lead, all species showed reduced germination in copper stress. Cadmium in lower concentrations were tolerable for plants but generally it had the greatest inhibitory especially on A. absinthium.

Overall the responses were different regarding to 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.

Oil contaminated soil is a vital threat to the environment. The aim of the present research was to investigate the total petroleum hydrocarbon (TPH), and heavy metals of nickel and vanadium reduction using Prosopis juliflora, under different treatments of biochar and compost in pots. One-year-old P. juliflora seedlings were planted in pots containing oil sludge. The pots included 1 and 2% of compost and biochar. Furthermore, two control treatments including with and without P. juliflora were used for the study. This study was conducted in the complete randomized plot sampling with three replications. After six months, soil samples were taken from the pots and transferred to the laboratory. Then, the concentration of TPH, nickel, and vanadium was determined. The results indicated that the least TPH belonged to the compost 2% treatment (10.63 ppm), which was significantly different compared with other studied treatments. The highest value belonged to the control treatment without P. juliflora (22.57 ppm). The highest value of vanadium belonged to the control treatment (69.50 mg/kg). Compost 2% had the least values of vanadium (47.66 mg/kg). Comparison between treatments showed no significant differences among compost 1% (117.17 mg/kg), compost 2% (118.00 mg/kg), and biochar 2% (116.67 mg/kg). The highest reduction of nickel was observed within the mentioned treatments. Therefore, using biochar and compost can improve the phytoremediation capacity of P. juliflora.

In the recent decade, the issue of soil contamination with heavy metals such as nickel and lead is one of the most important environmental problems. According to data from the environmental protection agency, nickel is hazardous at large amounts and a dangerous pollutant and lead is the most important pollutant in the environment. This study was conducted to investigate the soil pollution status of Gachsaran refinery using environmental indicators of pollution coefficient, pollution degree index and modified pollution degree index and to investigate the potential of alfalfa refining plant which is native to Gachsaran region.

From the soil of Gachsaran refinery in 2017 as the center of pollution, were selected four ranges of 0-500 meters, 1000-500 meters, 1500-1000 meters and 2000-1500 meters. In each range, 5 soil samples were taken from a depth of 0 to 30 cm. The ICP-OES device was used to determine heavy metals. Statistical analysis was performed using SPSS software.

The analysis of the environmental indicators of the studied area showed a significant degree of contamination for nickel and a high contamination rate for lead. Comparison of mean concentrations of nickel and lead in cultivated soil samples with alfalfa cultivars showed significant difference with mean nickel and lead concentrations in the studied area.

In general, Alfalfa as a native plant of the region in inappropriate pollution conditions can absorb and extraction nickel and lead from the soil. The final results of this study indicate that ability of alfalfa plant for phytoremediation of nickel in the soil contaminated with petroleum products is higher than that of lead in the Gachsaran refinery.

Phytoremediation can be one of the most promising techniques for elimination of pollutants from water and soil and environmental management. Through absorption and desorption processes, we can determine the level of maintenance for cations and anions. Based on transition factor of elements it is possible to specify that elements like Barium and Lithium have the least and elements like Cadmium and Boron have the highest accumulation. Soil pH also affects the level of availability and mobility of elements by controlling solubility of soil organic matters and it is in direct relationship with oxidation and reduction conditions. Absorption of ions by plant roots can be both passive (in direction of diffusion gradient) and active (against diffusion gradient using energy) processes. Phytoremediation is accomplished in four states including 1) phytostabilization and deposition of pollutants in the root, 2) phytoextraction that can be divided into two categories: continuous that requires the use of plants throughout their lifetime and induced by addition of accelerants or chelators to the soil, 3) phytovolatilization and transfer of contaminants from the root to leaves and the atmosphere and 4) phytofiltration to remove contaminants from water. For instance, to remove Arsenic, Cadmium (Zinc), Chromium, Mercury, Nickel, Lead, and Selenium plants such as P. vittata, T. caerulescens, Betula sp. tree, Amanita muscaria, Alyssum lesbiacum, Arabidopsis sp., and B. juncea could be used respectively.

Many ornamental plants have the ability to extract toxic metals from the soil and are able to store large amounts of metals in their organs with no health problems for humans as they do not enter the human food chain. This study aimed to investigate the effect of sewage sludge application on the performance of Helianthus annuus and to investigate its phytoremediation ability for heavy metals (Pb, Ni and Cd) in soil. This study was carried out with three levels of sewage sludge related to southern Tehran wastewater treatment plant, including 0, 10 and 20 percent by weight of soil in three replications in a completely randomized block design on Helianthus annuus. The results showed that the application of sewage sludge caused a significant increase in the concentration of heavy metals and wet and dry yield of different parts of the flower in the plant. Application of sewage sludge at 20 percent by weight of soil was more suitable for growth index and accumulation of heavy metals in plant in terms of growth index such as wet weight (root 12.03 g and shoot 48.56 g), dry weight (root 1.97 g and shoot 8.69 g), stem diameter (0.78 cm), stem height (19.4 cm) and flower diameter (7.44 cm) as well as concentration of heavy metals Pb (root and shoot 9.09 and 4.35 mg/kg respectively), Ni (root and shoot 3.65 and 2.04 mg/kg respectively) and Cd (root and shoot 0.598 and 0.364 mg/kg respectively). Due to root bioaccumulation factor above 1 and transfer factor less than 1, Helianthus annuus is a plant suitable for the uptake and transfer of heavy metals, which prevents the entry of heavy metals into the shoot parts by a plant stabilization mechanism.

Development of nuclear technology, mining, nuclear fuel cycle, and military operations are the most important reasons of radionuclides entrance to the environment. Transmission of soil radionuclides into the food chain is a major threat to human health in the long term. Therefore, removing these pollutants from the soil is extremely important. Phytoremediation is a simple and economical method that uses green plants to reduce or eliminate different types of soil pollutants. This technology is very practical and environmentally friendly. In this study wheat and sunflower plants were used to remove radium from soils of Saghand and Bandar Abbas mine's districts. Moreover, the effect of different concentrations of citric acid on the accessibility of plants to this element was investigated. In general, sunflower had better efficiency in radium absorption from soil of Saghand. In the case of Bandar Abbas soil, the amount of absorbed radium was more using sunflower plant, but more differences were observed in radium absorption by wheat plant at different concentrations of citric acid.

Landfills cause environmental degradation and pollution by producing greenhouse gases such as methane and carbon dioxide and producing leachate as well as contaminating surface and ground water. Recently, the ecological design approach as a framework for reducing environmental degradation by adapting municipal solid waste management to environmental processes is expanding widely. Ecological design strives to maximize comfort by minimizing damage to the environment and natural processes while enhancing people's quality of life. Ecological design strives to adapt to nature through the use of natural materials as well as environmental considerations.

In the present study, according to the definition of sustainable design and understanding its applications, in order to achieve the best, most complete and practical design for the site in question, existing maps of the area, including aerial maps, topography , GIS, vegetation, upstream maps, site development plans, survey of active sites in Landfill, survey of contaminant types, study of COD and BOD indices of the site have been studied, as well as review and identification of existing status  (Environmental, Physical, Climatic, Landscape, Land Use, Transportation, Biological) through observation, photography and interviewing strategic design of this area is provided with ecological-based approach by site staff and residents of neighboring neighborhoods in accordance with the principles and principles governing the design of industrial environments.

The existing plan prevents contamination of groundwater levels and prevents contaminated surrounding urban areas and agricultural lands. Restoration of damaged parts of the landfill, reduction of the risk of contamination by animals and noise pollution and unpleasant odors and its release into the atmosphere. The landfill is one of the main sources of greenhouse gas emissions in the country through biogas production from landfill gas collection and reduction of fossil fuel use. By collecting and using Landfill gases as fuel and power generation, the rate of emissions to the atmosphere is reduced. Maximum use of biogas is due to the greater use of digesters.

Design criteria are mainly based on existing constraints and needs and make the designer's policy clearer and significantly help in locating applications. Applying these criteria will help to enhance opportunities and take advantage of existing opportunities and make the project less threatening. After developing the strategies, designing from different perspectives is done to finally select the best plan for implementation by reviewing the concepts and comparing them with each other and in accordance with international standards. At the end of the study, the three concepts are finally selected and after examining these three concepts together, the winning concept is selected for the execution phase. Landfill is an inevitable step in waste management. In today's growing population, landfill has become an integral part of communities, but landfills should not be used as a last resort, but rather as a mean to create new uses for it. Converting landfills to recreational uses while also providing a pleasant place to meet the recreational and sporting needs of the area's inhabitants. Human landfill contaminates the area and destroys many animals and causes major disturbance in nature. Brings to enhance the quality of the landfills and with as the landfill site becomes more prone to disruption, it is necessary to look at the area as a demolished mosaic and take steps to repair it.

Heavy metals are elements with high atomic weight, and large amounts of these metals may be harmful to living organisms. Mercury is one of these metals and can cause various problems for human health. The aim of this study was to investigate the bioavailability of mercury by Afraplet species. With the permission of Natural Resources seedlings a year of Maple of nursery was prepared and the solution Chloride Mercury with concentrations of 20, 40 and 60 mg per liter of prepared solution is then added to the soil, and the seedlings of maple in the pot after the period of six months from growth of seedlings, leaves, stems and roots of the seedlings were sampled. Using ANOVA and Duncan test were examined.The highest level of Mercury accumulation in aerial organs in leaves, stems and roots and, respectively, 55; 40; 45.67; mg/kg. Based on the results of this research maple species suitable for remediation of soils contaminated with metal is mercury.

 Heavy metals are one of the most serious environmental problems that are spreading around the world. The present study was conducted to investigate the treatment of heavy metal contaminated soils by sunflower (Helianthus Annuus L.) under two natural remedies including municipal waste compost and biochar (each at three levels of 0, 1% and 2% by weight) done.

Design experiment was done in a completely randomized design with 5 replications. After planting period, aerial and underground parts of plant have collected and some soil important characteristics and plant morphological properties and metals have measured. ICP-OES is used for heavy metals measurement. Statistical analysis of measured data for the analysis of variance in SPSS software and comparison of data from the test at least significant difference (LSD).

The results showed that there was a significant difference between the application of treatments used in this study in the concentrations of cadmium, lead, zinc, chromium and nickel of shoots and roots of sunflower and the amount of total cadmium and soil exchange. Urban waste and biochar compost treatments increase the uptake of heavy metals cadmium, lead, zinc and chromium into the soil by sunflower.

According to the results of the present study, it can be generally stated that the sunflower species based on the values ​​of TF, BCF and BAC indices can be used as a plant suitable for phytoremediation of contaminated soils in the region through the plant process. Introduce stabilization. According to the results of this study, sunflower can be used as an adsorbent of pollutants and is recommended in soils contaminated with heavy metals.

The existence of heavy metals in the aquatic ecosystem has caused several environmental problems for many years especially in the industrial regions. These elements enter the environment as a result of natural factors, industrial activities and urban sewage, and accumulate through the food chain in the body of aquatic organisms. The mangrove plant plays an important role in the food chain due to its ability to accumulate metals in its organs. In this study, the ability of mangrove plants to adsorb heavy metals (vanadium, cobalt, lead and mercury) which contaminating the Assaluyeh area was investigated. The plants were made from semi-finished seedlings located in Deir (Booshehr province) and treated in the pilot environment with concentrations of 40, 50 mg / L and 3200, 350 micrograms / liter of pollutants at pH 7.8 for 14 days. Samples which were collected from plant organs were digested in concentrated acid and the then concentration of metals was measured using atomic absorption spectrometry. Considering the experimental data it can be concluded the purification of vanadium, mercury and lead ions from aqua medium increase while adsorption of Cobalt ion decreases by increasing time. Finally, the highest absorption by this plant was related to vanadium, mercury, lead and cobalt ions, respectively, at pH 7.8.