Content of potentially bioavailable polycyclic aromatic hydrocarbons in rhizosphere soil in relation to properties of soils

Abstract

The aim of the present study was to evaluates the content of mild-solvent extracted fraction of the polycyclic aromatic hydrocarbons in the rhizospheres of some selected plant species (Cucumis sativa, Daucus carota, Allium cepa, Cucurbita pepo, Petroselinum sativum, Cucurbita sp., Phaseolus vulgaris, Beta vulgaris, Apium graveolens, Allium porrum, Vicia faba). Ten cd]pyrene) were chosen. The polycyclic aromatic hydrocarbon (PAH) content was determined using the HPLC method with UV detection after a preliminary sample treatment with ultrasonic techniques. On the basis of the PAH content, the organic carbon content and the value of log K oc , (equilibrium partitioning model) a soil pore water PAH fractions present in the rhizospheres of the plants studied were calculated too.The content of the fraction extracted with n-butanol within the total of 10 PAHs ranged from 55% to 90% (mean 74%). Similarly, as in the case of the total of the 10 PAHs, significant differences in the content of PAHs extracted with n-butanol were also noted for the individual compounds studied. The content of the total of the 10 PAHs as determined from equilibrium partitioning model in relation to plant species ranged from 0.03 to 0.18 mgykg which constituted from 0.07% to 0.15% of the total content of these compounds. No clear relations between soil properties and the content or contribution of potentially bio-available PAH fractions have been observed.

Influence of Long-Term Soils Flooding by Distilled and Post-Sewage Water on Polycyclic Aromatic Hydrocarbons (PAHs) Changes

“…However, only in soil MS, a series of significant relationships between a change in the PAH content and Ca 2+ content were found ( Figure 6). In the earlier studies (Oleszczuk & Baran, 2004b, 2006 attention was drawn to a significant role of the sorption complex (where Ca 2+ is a predominant cation) in the PAH bioavailability. Hence, it can be assumed that long-term soil flooding changed the structure of organic matter, which, in turn, mobilised pollutants and their diffusion from the hard-to-access and impossible-to-access places in the soil matrix.…”

The Influence of Crops on the Content of Polycyclic Aromatic Hydrocarbons in Soil Fertilized with Manure and Mineral Fertilizers

“…Crop species can exert varied effects on different types of soil-dwelling bacteria, and root secretions can accelerate the biodegradation of pollutants [ 61 , 62 ]. Root secretions contain chemical compounds that are characteristic of a given plant species and influence soil microbial communities [ 63 ].…”

Combined Effects of Plant Cultivation and Sorbing Carbon Amendments on Freely Dissolved PAHs in Contaminated Soil

“…Many sites have abundant vegetation, therefore from a practical point of view, understanding the effects of plants on the content of C free PAHs in relation with biochar or AC application is advantageous. It has been shown that plants may increase bioavailable PAHs in soil. , Conversely, the plant rhizosphere may affect the degradation of PAHs and thus stimulate the growth of microorganisms . However, biochar or AC addition to soil may also reduce the availability of nutrients necessary for plant growth and thus limit the applicability of this remediation technique.…”

“…It has been shown that plants may increase bioavailable PAHs in soil. 25,26 Conversely, the plant rhizosphere may affect the degradation of PAHs and thus stimulate the growth of microorganisms. 27 However, biochar or AC addition to soil may also reduce the availability of nutrients necessary for plant growth and thus limit the applicability of this remediation technique.…”