Evaluation and transport of nitrogen and phorphorus by river Indus at Kotri barrage

Water samples at Kotri barrage were collected during Jan 1994 to Dec. 1995 and analyzed for nitrite, nitrate, ammonia, organic nitrogen, orthophosphat e and condensed phosphate. The concentrations were multiplied with water di scharges to obtain load of each ion including total nitrogen and phosphorus in the river Indus. The transport of nitrogen and phosphorus to Arabian se a and to irrigation channels at Kotri barrage were calculated. The variatio n in their phosphate phosphorus were dominant and contributed 64% and 73% o f total nitrogen and phosphorus transported.