Xorazm ma ’ mun akademiyasi axborotnomasi – /2020 Ўзбекистон республикаси фанлар

XORAZM MA
’
MUN AKADEMIYASI AXBOROTNOM
А
SI 
–
9/2020 
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that can be absorbed by nickel, copper and zinc plants, and more than 400 plants, can easily absorb 
them and "completely remove" them from soil and water [24]. 
 
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Immobilization of soil by collecting or precipitating soil pollutants in rhizospheric 
region by collecting or precipitating pollutants is called phytostabilization. [2]. 
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Organic disintegration of organic pollutants in plants, either internally or via 
metabolic pathways, using isolated enzymes or exogenous root exudates and incorporating these 
pollutants into plant tissues [22]. This process is mainly used to break down complex organic 
molecules and convert them into simple forms in soils, groundwater environments and sludge [13]. 
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Rhizodegradation (Phytostimulation). The decomposition of contaminants in the soil 
as a result of the activity of microorganisms with increasing root zone is called rhizodegradation 
[21]. According to USEPA [23], the number of microbes in the rhizosphere region is at least 100 
times higher in 2000 than in non-rhizosphere regions [1]. 
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Phytovolatilization. During phytovolatilization, pollutants such as selenium, 
mercury, arsenic, and others absorbed by the roots of plants become more simple forms and then fly 
into the atmosphere through the leaf stomata. In the process of phytostabilization, metals are 
absorbed into the organic compounds that are naturally volatile and are released into the atmosphere 
as biomolecules [9]. 
Small amounts of heavy metals are essential for plant growth and metabolism; however, at 
high concentrations they can be harmful to plants and hence the soil ecosystem [11]. 
Phytoremediation is a bioremediation system used by plants to remove contaminants from soil, 
sludge, sediments and groundwater [5].
 
Phytoextraction for lead and zinc-contaminated soil 
Figure 1 presents the conceptual basis for the impact of plants on heavy metals under the 
influence of environmental factors and human activity.