Prediction of storm wise phosphorus load in river using rainfall and runoff variables (case study: Kojour watershed)

Phosphorus (P) is an important nutrient for plants، in other hand P contaminates water resources. The present study aimed to access the applicability of rainfall and runoff variables of seven storm events occurred during 2008 in prediction of storm-wise peak and average P concentration and total P loss in Kojour watershed with the help of bivariate and multivariate regression models. Towards this attempt، seven storm events occurred during study period were analyzed، samples of river were collected for seven events with time intervals of 1 h. The results verified the capability of regression model with relatively high determination and efficiency coefficients of 0. 884، 0. 883 respectively. The results could facilitate the application of given methods obtained in the present study to other areas with similar conditions and leading to the suitable soil and water management.