Interactions between contaminated aquatic environments and element uptake by Echinodorus amazinocus and Cryptocoryne undulata

Effects of inorganic arsenic species on the antioxidant enzyme system of the Amazon Sword Plant (Echinodorus amazonicus Rataj)

This study aims to examine the effects of Arsenite (As⁺³) and Arsenate (As⁺⁵) on the aquatic macrophyte Amazon Sword Plant (Echinodorus amazonicus Rataj). To this aim, different concentrations of As⁺³ and As⁺⁵ (0, 6, 18 and 54 μM) were analyzed. At the end of the trail, photosynthetic pigment contents, total protein amounts, the enzymatic antioxidants superoxide dismutase (SOD), peroxidase (POX) and catalase (CAT) activities and the amount of malondialdehyde (MDA) in the leaf samples of E. amazonicus were investigated. The antioxidant enzyme activities increased at low concentrations (32.13% for SOD, 185% for CAT and 201.5% for POX in the groups of 6 μM As⁺⁵), but decreased at high concentrations (64.98% for SOD, 21.64% for CAT and 21.29% for POX in the groups of 54 μM As⁺³). MDA increased in all the treatment groups. The highest MDA contents were observed as 96% for 54 μM As⁺³ and 71.50% for 54 μM As⁺⁵. Photosynthetic pigment contents and the amount of protein were decreased with higher concentrations. The most significant decreases in protein content were 65% for 54 μM As⁺³ and 34.9% for 54 μM As⁺⁵. As a result, the toxicity of As⁺³ was higher and the toxic effect increased at higher concentrations.

Investigation of Direct Applicability of Modified Agricultural Waste for Contaminant Removal from Real Textile Wastewater

The textile industry produces enormous volumes of wastewater which must be treated effectively. In this study, biosorbent from the agricultural waste of potato peels (PP), which is environmentally friendly and easy to find everywhere, was used for the treatment of real textile wastewater. Physical modification, chemical activation, bio-hybrid and high-pressure modification processes were applied to PP to investigate the organic pollutant removal (chemical oxygen demand (COD)) and inorganic (Fe2+, Ni2+, Cu2+ and Cd2+) from original textile wastewater. Additionally, the effects of contact time (5, 15, 30, 60, 120, and 1440 min) and particle sizes (1.5–1.0 mm, 1.0–0.5 mm, and smaller than 0.5 mm in diameter) were investigated in a batch treatment system. Application of the physical modification process to PP presented an attractive solution for COD removal efficiency (69.50%) and removal efficiencies for four divalent metal ions; 78.6% for Cu2+, 63.6% for Ni2+, 40% for Fe2+, and 34.6% for Cd2+. FT-IR, SEM, and EDX analysis were performed to reveal the adsorption mechanism of the modified adsorbents. The FT-IR results indicate that the adsorption process fits the chemical and physical removal mechanisms, which were also supported by SEM images and EDX results.

Heavy Metal Uptakes by Myriophyllum verticillatum from Two Environmental Matrices: The Water and the Sediment

To determine the preferred elements of the benthic plant Myriophyllum verticillatum, changes in the element concentrations in the plant were investigated in laboratory condition. The reactor was fed with synthetically contaminated water consisting of 2×10(-6) M of the heavy metals Fe, Cr, Zn, Ni, and Cu for 1060 hours. The elements that were preferentially taken up by the tested plant body were evaluated with respect to translocation factor, bio-concentration factor, and the amounts of partial elements and relative uptakes. Both the changing physical properties of the aqueous solution in the reactor during the experiment and the growth of the plant were tested using a two-sample t-test. The Zn and Cu levels in the combination of the leaves and stems were found to be significantly higher than the levels in the roots at the end of the trial. Based on the partial amount of each element, the affinity of the plant for different elements was found to follow the order of Ca>Fe>Mn. Scanning electron microscope (SEM) analyses of the plant bodies indicated that these elements were located both inside the organs and on the surface of the tissues alone or with microorganisms such as diatoms.