ABSTRACT
Macrophytes take up metals from water, producing an internal concentra tion several fold greater than their surroundings. They play a crucial role in biogeochemical cycling of trace metals. The submerged plant thickets in polluted lakes are reported to accumulate trace metals to the tune of 103-104 or reduce the water velocity there by accelerating sedimentation of the suspended fine par ticulate trace metals, which otherwise are toxic to the biota when present in the interstitial waters in available form (2,3).
