BIOTIC PARAMETERS OF THE RIVER YAMUNA IN RELATION TO POLLUTION STATUS

mong biotic communities in river Yamuna, plankton population ranged from 237 ul-1 to 2570 ul-1, periphyton 917 ucm2 to 4913 ucm-2 and bottom biota 100 nom-2 to 1366 nom-2. Euglenophyceae was not recorded in upper and lower stretch while it was maximum in the middle stretch. Molluscs were noticed in lower stretch only. Diversity index lies between 0-2.9 indicating moderate to high pollution in the river Yamuna. Increased percentage of zooplankton in the middle stretch particularly at Delhi and Mathura is also a symptom of eutrophication. Palmer algal genera pollution index also revealed heavy pollution in the middle stretch of the river. Key words: Plankton, periphyton, benthos, abundance, composition, pollution, diversity