Pollution Research Paper

IDENTIFICATION OF SUITABLE SPECIES OF SUBMERGED HYDROPHYTES FOR CONTROLLING ALGAL BLOOMS IN EUTROPHIC WATER BODIES

PRIYANKA PAREEK, SHWETA SHARMA, SUBHASINI SHARMA AND K.P. SHARMA

Abstract

Growth of explants of Potamogeton crispus L., P. pectinatus L., Hydrilla verticillata (L.f.) Royle and Ceratophyllum demersum L. was assessed in eutrophic microcosms along with their role in regulating algal populations. Explants initially grown in Hoagland (Control) and Hoagland + 0.5ppm copper (treatment) for 7days (12 days in P. pectinatus) were transferred into microcosms kept in an experimental plot open to sky (outdoor studies; direct sun light exposure to about 8h) and in the greenhouse having direct exposure to sun light for about four hours. Shoot length, chlorophyll content, shoot dry weight and relative growth rate (RGR) were found maximum in P. crispus shoots growing in the outdoor while in Ceratophyllum growing in mixed culture with Hydrilla in the indoor. Among controls, minimum number of phytoplankton was found in microcosms having P. pectinatus shoots whereas in treatments, it was in P. crispus in the outdoor study and in mixed culture of Ceratophyllum and Hydrilla in the indoor study. Copper treatment aving little adverse effects on shoot growth however, decreased phytoplankton counts effectively in microcosms having P. crispus (outdoor study) and mixture of Ceratophyllum and Hydrilla (indoor study). Based on our findings, P. crispus in combination with P. pectinatus and Ceratophyllum shall be suitable for controlling algal bloom through biomanipulation.