Estimation of nutrients load of Pupa River basin (LakeEgirdir,Turkey)

The Pupa River basin, located in south-east Anatolia, inflows it's waters to the Lake Egirdir. The purpose of this study were to investigate present status of the basin?s nitrogen and phosphorus compounds quantitatively and qualitatively, and to estimate nutrients loading rates from the basin to Lake Egirdir that is a pollution causative factor for the lake and to suggest pollution control measures that can be applied for Lake Egirdir on the basin level, based to the investigations and estimations. Nutrient concentrations of the Pupa River?s Basin were determined through seasonal samples obtained at 7 sampling points between August 2011 and May 2012. In the same time investigations were made and fertilizers and manure usage data in the basin were collected. The Basin?s nutrient load was found by multiplying the mean nutrient concentrations of surface waters resulting from the analyses by the Basin?s net water gain. The nitrate nitrogen, ammonia nitrogen, total nitrogen, orthophosphate and total phosphorus loads per year for the Lake Egirdir coming from the basin were estimated as 205004 kg; 184870 kg; 197683 kg; 560624 kg; and 570561 kg, respectively. It can be seen that artificial fertilizers and animal manures used in the basin are efficient on nutrient load of the basin and it was established that these fertilizers potentially caused water pollution in the area. On the investigations it can be clearly seen that the Pupa River's Basin is influenced by pollutants as municipal wastes which are passed into the surface water without any treatment or purification, and agricultural wastes and fertilizers. There is an urgent need for taking precautions for minimizing the nutrient load coming from the basin into surface and groundwater. And measures should be taken in municipal waste water treatment and in good agricultural practices such as less and on time fertilizer usage.