Biomass reduction of Salvinia molesta exposed to copper sulfate pentahydrate (CuSO4.5H2O)

Abstract

Copper in the aquatic ecosystem may remain adsorbed or be incorporated into the biomass and undergo biomagnification causing unwanted effects to aquatic macrophyte communities. This study evaluated the biomass reduction of Salvinia molesta (Mitchell) exposed to copper sulphate pentahydrate (CuSO 4 .5H 2 O) under laboratory conditions. Approximately 20.5 g of fresh mass (FM) of S. molesta (0.74 g dry matter, DM) were placed in glass tanks with different concentrations (n = 3) of CuSO 4 .5H 2 O as follows: 0.0; 2.0; 4.0; 6.0; and 8.0 mg L -1 for 28 days. The dry mass was determined after each seven-day interval over 28 days and submitted to repeated ANOVA measures, followed by a Tukey test (P<0,05). The results show that macrophyte increased until the seventh day of exposure in all treatments. After this period, the biomass of S. molesta decreased; but there was no significant difference between treatments with copper, except for the 8.0 mg L -1 treatment. The copper treatments decreased the S. molesta biomass an average of 43.2% (0.50 g DM) after 28 days. At the end of the experiment, copper absorption in the treatments with 6.0 and 8.0 mg L -1 was on average 77.9% higher than in the treatments with 2 and 4 mg L -1 .

Copper accumulation by the root and leaf biomass of Salvinia natans (L.) All. (Salviniaceae)

“…The greater accumulation of copper ions by the roots of S. natans was expected considering that this plant is classified as a floating free macrophyte and its root system maintains direct contact with the ions of metals dissolved in the water and have, in general, a larger area of abortion than the leaves (Barros & Henares, 2015). In the study with leaves, stems and roots of Potamogeton pectinatus L. exposed to different concentrations of Cu, it was observed that in all treatments in the root biomass there was a higher concentration of the metal (Costa et al, 2018).…”