Investigating the effect of climate on sediment production and loss of phosphorus and calcium carbonate by sedimentation in the basin of Gorganroud, Golestan Province

The study of sediment quality indicators in the basins of Gorganroud, as one of the most important part of Golestan province, can give us a better understanding of water pollution, sediment contamination and their effects on aquatic organisms. study was conducted to determine the effect of climatic condition on the quality and quantity of sediment and nutrients loss at various points of the catchment. Four dams along the river (Bostan, Golestan, Voshmgir and the Khajeh nafas) were selected and sediment sampling was performed at the depth of 0-30 cm on the location of the input on each dam. The data were analyzed in nesting factorial model in three replications. With respect to the average rainfall of 12 years (1380- 1391), which was 608.8 mm at the Tamar station and 445 mm at the Aghghala station, amount of nutrient loss was various in different parts of the river. The results showed that amount of phosphorus varied between 13.37-42.18 mg/kg along the river and entrances. In addition, significant diference were observed between the amount of lime and organic matter in all four different regions and varied from 16.4 to 30, 0.890 to 1.6% respectively. The cation exchange capacity was in the range of 6.5-37 cmol/kg. Current study shows that the climate could play a crucial role in erosion, sediment regeneration and nutrient loss in different parts of the studied Basin.