limitations Advantages: the cost of the phytoremediation is lower than that of traditional processes both in situ and ex situ the possibility of the recovery and re-use of valuable metals (by companies specializing in "phyto mining") it preserves the topsoil, maintaining the fertility of the soil Increase soil health, yield, and plant phytochemicals the use of plants also reduces erosion and metal leaching in the soil Limitations: phytoremediation is limited to the surface area and depth occupied by the roots. with plant-based systems of remediation, it is not possible to completely prevent the leaching of contaminants into the groundwater (without the complete removal of the contaminated ground, which in itself does not resolve the problem of contamination) the survival of the plants is affected by the toxicity of the contaminated land and the general condition of the soil bio-accumulation of contaminants, especially metals, into the plants can affect consumer products like food and cosmetics, and requires the safe disposal of the affected plant material when taking up heavy metals, sometimes the metal is bound to the soil organic matter, which makes it unavailable for the plant to extract Processes A range of processes mediated by plants or algae are tested in treating environmental problems.: Phytoextraction Phytoextraction (or phytoaccumulation or phytosequestration) exploits the ability of plants or algae to remove contaminants from soil or water into harvestable plant biomass. It is also used for the mining of metals such as copper(II) compounds. The roots take up substances from the soil or water and concentrate them above ground in the plant biomass Organisms that can uptake high amounts of contaminants are called hyperaccumulators. Phytoextraction can also be performed by plants (e.g. Populus and Salix) that take up lower levels of pollutants, but due to their high growth rate and biomass production, may remove a considerable amount of contaminants from the soil. Phytoextraction has been growing rapidly in popularity worldwide for the last twenty years or so. Typically, phytoextraction is used for heavy metals or other inorganics. At the time of disposal, contaminants are typically concentrated in the much smaller volume of the plant matter than in the initially contaminated soil or sediment. After harvest, a lower level of the contaminant will remain in the soil, so the growth/harvest cycle must usually be repeated through several crops to achieve a significant cleanup. After the process, the soil is remediated. Of course many pollutants