چكيده لاتين :
Two laboratory experiments were conducted to evaluate the amount of P utilization from two
different types of sparingly soluble phosphate rock by aquatic biotic communities. The first type was Mussoorie
Phosphate Rock or MPR (sedimentary in origin) and other was Purulia Phosphate Rock or PPR (igneous in origin).
The two trials were with eight different treatment combinations. Among various treatments, fish and Chironomid
larvae contributed to some extent in increasing the available sediment phosphate content which in tum increased the
soluble reactive phosphate (SRP) of overlying water. Concentration of SRP of overlying water decreased in the
treatment with zooplanktons. Depletion of SRP of overlying water due to uptake of orthophosphate by Chlorella was
also observed. The sedimentary type phosphate rock proved to be more efficient in releasing phosphate than igneous
one.