Phytoremediation of Metal Contamination for Mine Rehabilitation
Introduction
For environment safety, Phytoremediation is used as an effective process which helps in removing the contaminated soil which harms the environment and human life to a large extent. In developing economy, there are large number of metal manufactures sites worldwide which pollutes the human activities (mining, gas exhaust, energy and fuel) and mining activities (crushing, grinding, and washing) (Moosavi and Seghatoleslami, 2013). In addition, mining wastage and release of metal contaminates affects directly and indirectly to the animals and human beings DNAs and to overcome, it is important to remove heavy metals usage from sites. Metal contaminated soil can be removed through different techniques like chemical, physical or biological and in that biological techniques involve Phytoremediation process (Ali, et al., 2013). This process is emerging plant based friendly environment and a cost-effective technology that plays an important role in ecology restoration and human and animal life safety at land mining.
Phytoremediation uses the different types of green plants for removing, transferring, degradation and containment of contaminates from soils and groundwater. The phytoremediators is an emerging technology which effectively uses it for remediating of metal contaminated in the soil. According to Neilson and Rajakaruna (2015), Phytoremediation is effective biological or bioremediation process where it uses various plants in order to remove, destroy and stabilize the contaminants from the soils and water which affects directly or indirectly human and animal life. This technology is used widely as it is innovative, cost effective and most established treatment method which is used at hazardous waste sites (Singh, et al., 2012). The main purpose behind developing a phytoremediation is to clean up the soil which is highly polluted from large metal contaminant.
Generally, heavy metals are highly and naturally present in the environment as well as generated from man-made processes. The man-made processes affect the environment in large manner in terms of different types of air, noise and soil pollutants and metal contamination which affects the living and safety life of human and animal on earth. Evangelou, et al., (2015) demonstrated that plants are used as phytoremediators for lighting up the contaminated soil and water in which material are treated as medium depth and area is illustrated as a large. This is effective phytoremediation process in comparison to other methods which are used to remove the toxic substances which are present in soil.
Importance of Phytoremediation
The importance of phytoremediation is high as it helps in removal of contaminated metal for mining rehabilitation. In concern to it, Belliturk, et al., (2015) stated that in research it is found that green plants has shown effectives response towards the presence of potential toxic concentrations in heavy metal ions. But at the same time, Arslan and Ullah (2016) argued that there are some plants which are sensitive and have low concentration toward heavy metals ions. In agriculture sector, phytoremediation is used as a tool for achieving a sustainable agriculture for metal contamination of soil. Through this tool, new plants are used and highly adapted in agriculture in order to accumulate the toxic trace metals at the time of growing in contaminated soil.
At mining sites, Phytoremediation of metal contaminated soils basically includes phytoextraction and Phytostabilization. Phytoextraction is also known as phytoaccumlation which is used as a strategy for translocation of metal contaminants in the soil through plant roots to above grounded plant components (Kiran and Prasad, 2017). On the other side, Phytostabilization is used an efficient method that uses the plants in efficient manner for reducing the mobility of contaminant by preventing erosion and also by reducing the bioavailability of pollutant in the environment.
The discovery of contaminated metals in the soil resulted into development of phytoremediation technology which is developed with an aim to remove, destroy the heavy metals contaminates from the environment. In the research study of Valipour, et al., (2014), it is determined that there are different method which s used in this process which support the phytoremediation will cleaning up the contaminated metal soil from the mining sites. Thus, depending upon this process leads to plants removing and reducing their toxic effect of contaminants from the metal. The process of phytoremediation is different as it focuses on different factors like environmental factors (climate condition, irrigation, soil fertilization) and soil & plant characteristics (plant species, plant tissue, pH, clay content and so on).
Ye, et al., (2015) demonstrated that the process of phytoremediation is controlled by other plants for which it required a large time to grow a plant and transfer or remediate the metal & soil contaminant through mining rehabilitation. There are various methods which are used as a process of phytoremediation during metal contaminant such as phytostimulation, phytostabilization, phytotransformation, phytoextraction, phytofiltration and so on. In concern to it, Rajkumar, et al., (2012) the basic process of phytoremediation is growing the plant and developing plants roots in depth.
Advantage and disadvantage of Phytoremediation
There is various advantage of phytoremediation which influence the treatment level of contaminated metal in terms of mining rehabilitation. The cost phytoremediation is low because it required less capital and operating cost for its process in which metal recycling also provide economic advantages. For successful phytoremediation process, there is a high need of best supportive phytoremediators method which helps in removing the contaminated from the soil from the land metal is mined.
At the same time, Chekroun and Baghour (2013) determined that performance o phytoremediation is effect and efficient as it provide permanent treatment solution for the metal contaminated. This phytoremediators is efficient enough in removing or eliminating the secondary air or water borne wastes from the soil which is contaminated or in the large area of mining. Moosavi and Seghatoleslami (2013) explained that phytoremediators is capable of remediating or removing the bioavailability to a large extent by avoiding the excavation through which fraction of contaminants are remediated.
A major disadvantage of phytoremediators of metal contaminant is high concentration of heavy metals or combination adversely affects the plant growth and biomass production to large extent. The research study of Prasad (2013), it is clearly stated that there are some plant species that have an ability to grow and develop in rich metal soils like in the area of mining sites. The other disadvantage which is identified is that the performance of phytoremediation is not 100% as it is not capable or has the chances of failure due to high contaminant toxic available in the plants. The soil phytoremediation is only made available for the contaminated surface soil. In addition to it, Singh, et al., (2012) depicted that for phytoremediation there is need of high area like in groundwater application, there is a need of large surface area. On the other side, there is lack of recognized economic performance data which influences adversely on the process of reducing the metal contaminant.
Limitation of Phytoremediation
The limitation of phytoremediation is limited to the mining sites as the depth of contaminants is treated limited. The use of phytoremediators is found high as mining sites have limited area with lower contaminant concentrations and also with contaminant soil and groundwater. In addition, Achal, et al., (2012) elaborated that disposal of harvested plant develops an problem for economy as these plants may contains the high level of heavy metals. The treatment zone help in determining the depth of the plant root and also in some cases, it is limited in concern of shallow soil, streams and groundwater.
However, in the research study of Cameselle, et al., (2013), it is clearly identified that the use of tress in mining sites allows them to treat the contaminants deeper because tree roots enters efficiently and deeply into the ground. At the same time, the success of phytoremediation is highly dependent on the seasonal factor and location. The seasonal climate always influences the effectiveness of phytoremediation as establishing a selected plant community to mining sites leads to remediation of contaminants. According to Sarma (2011), there are some challenges in phytoremediation process which increases different feasible alternative as well as it is very promising strategy in terms of metal contaminants. The availability of metals in the soil is another limitation of phytoremediators at the time of plant uptake.
From the above discussion, it can be concluded that Phytoremediation plays a significant role in which it is uses different types of plants to remove and destroy contaminates from the soil and groundwater. This paper explained the importance of phytoremediation for removal or destroying of metal contaminates during mining process. The process of phytoremediators is very effective for which time is required as this process is successful as it is dependent on seasonal climate. Further, this study helped in understanding the actual advantage of phytoremediation in terms of cost and performance but also identified its disadvantages like time, space and many more while reducing of metal contaminant for mining process. Therefore, it can be concluded from this study that phytoremediation is successful emerging technology developed in order to avoid and eliminate the contaminants from the soil and metal.
References
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