Macroelements and Heavy Metals Content in Panicum Virgatum Cultivated on Contaminated Soil Under Different Fertilization

Abstract

SUMMARYHeavy metal contamination of soils is a major problem worldwide. As a result, arable land polluted with heavy metals is unsuitable for food production. Utility of energy crops which allow the commercial exploitation of these soils by establishing biofuel feedstock production systems can offer a solution. Additionally, plant cultivation offers opportunities for site remediation.Field experiments have been performed on heavy metal contaminated arable soil located in southern Poland, in the vicinity of a former smelting factory. Although heavy metal concentration exceeded standards, the area has been used for agricultural purposes. Experiments involved testing Switchgrass (Panicum virgatum) cultivated with standard NPK fertilizers and commercially available microbial inoculum. Biomass water, macronutrients (N, P, K, Mg, Ca) and heavy metal (Cd, Pb, Zn) content in aboveground plant organs were assessed at the end of two growing seasons.Switchgrass biomass water content was higher after the second year for nearly 40%. Additionally, after the first as well as the second year fertilizers increased it. Magnesium content, essential in chlorophyll biosynthesis, was higher in the first year and additionally more evident in fertilized variants after every year. Heavy metals accumulation in aboveground organs was lower after the second year compare with the first year. Similar trend was observed for Ca and N plant accumulation. However P and K accumulations were higher after the second year of experiment.In conclusion, due to acclimatization, switchgrass reduce heavy metal uptake, what could result in increase of two biogenic elements (P, K) essential in plant growth.

Hazardous pollutants in agricultural soil and environment

“…This difference can be ascribed to the use of mineral fertilizers in previous years, whose contribution may have increased their soil concentration (Nemera et al, 2018). This observation can also be extended to the other analyzed macroelements, which had higher average concentrations in conventional treatment but were not statistically different (Pogrzeba et al, 2018). Another significant difference found in the soil between treatments was the higher pH values in the conventional treatment.…”