Respiratory Metabolism of the Higher Aquatic Macrophytes under the Effect of Manganese Ions (II) of the Aquatic Environment

Abstract

Peculiarities of the influence of the manganese ions (II) in concentrations close to those in the natural water bodies on photosynthesis and respiration of the submerged higher aquatic plants Najas guadelupensis L., Ceratophyllum demersum L. and filamentous green algae Oedogonium cardiacum (Hass.) Wittr., Cladophora glomerata (L.) Kütz have been studied. It was found that impact of 5-20 μg/dm3 Mn2+ during 24 hours caused intensification of photosynthesis and respiration of the studied macrophytes. In the two-week experiments it was found that respiratory metabolism in N. guadelupensis and C. demersum was depressed at the lower concentration (50 μg/dm3 Mn2+), than in Cl. glomerata (100-200 μg/dm3 Mn2+); any toxic effect of 5-200 μg/dm3 Mn2+ for the respiratory metabolism in Oe. cardiacum was found. Accumulation of the manganese ions by macrophytes has been studied. By ability to accumulate this metal they may be arranged in a sequence: Cl. glomerata > Oe. cardiacum > N. guadelupensis > C. demersum. It is recommended to use Oe. cardiacum and Cl. glomerata as biomonitors of the water pollution by the manganese ions.