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Microspheres (MSs) of paramagnetic iron oxide (α-Fe2O3) embedded with palladium nanocubes (PdNCs) were biosynthesized using Myrtus cumini L. leaf extract. The synthesized PdNCs embedded α-Fe2O3 microspheres were characterized using FTIR, XRD and SEM/EDX. The FTIR spectrum of the Myrtus cumini L. leaf extract confirmed the presence of phenol, ester and amine groups that were involved in the bio-reduction of PdCl2 to PdNCs. SEM/EDX revealed that the PdNCs with size range of 15–250 nm were present on the surface of the synthesized microspheres. Box-Behnken Design (BBD) was employed for optimization of Methyl Orange (MO) decolorization using α-Fe2O3MSs and PdNCs embedded α-Fe2O3MSs at pH (1, 2 and 3), catalyst dosage (1, 3 and 5 g L-1) and reaction irradiation time (30, 60 and 90 min). It was found that PdNCs embedded α-Fe2O3MSs had maximum decolorization of 96.56 % at pH 1.72, catalyst dosage 2.69 g L-1 and irradiation time 68.34 min.

A simulated wetland experiment was used to investigate the effect of cadmium (Cd) on the growth of Arundo donax, as well as its photosynthetic characteristics and antioxidant enzyme activities. Cd accumulation in the order of stem < roots < leaves increased gradually with increasing Cd concentrations. Due to the higher transport of Cd, its accumulation in the aboveground parts of A. donax was nearly 2 times that in belowground parts. There were no differences in physiological parameters, such as the relative chlorophyll content (SPAD), the potential (Fv/Fm) or effective (Y) photochemical efficiency of PSII, and photosynthetic rate (Pn). There were slight changes in transpiration rate (Tr), intercellular CO2 concentration (Ci) and stomatal conductivity (Gs). The activity of superoxide dismutase (SOD) was stimulated by Cd treatments, and the decrease in catalase (CAT) was compensated by the induction of peroxidase (POD) suggesting these two enzymes function concurrently to remove H2O2. These results indicate that despite the oxidative stress involved in the mechanism of Cd toxicity associated with the high transport of Cd in A. donax, its photosynthetic system was not harmed. This suggests a strong tolerance of this species to increased Cd pollution and its potential use for phytoremediation purposes in wetland environment.

Ashes, formed as a result of combustion of biomass are a new class of by-products of combustion and due to the large variety of these materials their chemical composition has not been fully determined. Their use is limited, despite the fact that their production has increased. This work presents the results of studies on the possibility of limiting the potential availability of Cu, Mn, Pb and Zn for plants by use of an inorganic stabilizer - ash from biomass combustion. In this study the usefulness of ash from biomass for binding mobile fractions of heavy metals (Cu, Mn, Pb and Zn) was evaluated. The investigations were executed using three extraction tests with the use of the following extraction solutions: 1 M HNO3 – acid soluble forms (As), 0.05 M EDTA – bioavailable forms (Bio), 2.5% CH3COOH – exchangeable forms (Ex). The values of the following parameters: Mobility Index (MI), Contamination Factor (CF), Pollution Load Index (PLI), Geo – accumulation Index (Igeo) and Ecological Risk Index (RI) were defined and determined for their suitability as a test soil stabilizer. Furthermore, a multivariate statistical analysis was carried out. It was found, that a phytoremediation process using investigated ash from biomass combustion can be applied to soil contaminated by heavy metals.

Natural diversity of intermittently closed and open lakes and lagoons (ICOLLs) depends on mutual interactions of several factors: (i) an impact of sea water and land background; (ii) temporary meteorological situation; (iii) hydrological conditions; and (iv) the shape of lake basin. However, some regional, local or even sudden impacts including anthropogenic ones create their final ecological status. To identify heavy metals risk assessment in ICOLLs located in Polish coastline wide range of them were determined in water and bottom sediment samples collected in 10 water reservoirs. Multidimensional data set of 20 variables was explored by the use of chemometrics according to seasonality (Spring, Summer, Autumn), sample type (water, sediment) and level of isolation (fully isolated, partially and fully connected lakes). The results showed that 70.5% and 77% of the data variance can be explained by the use of principal component analysis for waters and sediments, respectively. Waters of fully isolated or partially connected lakes are more abundant with Ir, Nd and Sm, while less abundant with Pr and Sr. Bottom sediments taken from Jamno lake show significant contamination by heavy metals of the highest environmental concern (Al, Cr, Cu, Ni, Ti and Zn).