Determination of the aquaculture carrying capacity of Eşen-1 HES dam lake (Seydikemer-Muğla)

In Mugla province, where net cage farming is still in practiced inland lakes, the Eşen 1 Hydroelectric Power Plant (HEPP) dam is a significant asset. In terms of sustainable aquaculture, the amount of rainbow trout produced in one production period and its environmental implications are critical. This research was conducted between 1 December 2019- 30 June 2020, with the goal of determining the carrying capacity of rainbow trout in net cages in Eşen 1 HEPP Dam Lake based on nitrogen and phosphorus, and other revealing feed-related effects during the production period in the Eşen 1 HEPP dam lake. In six different stations, researchers wanted to see how rainbow trout aquaculture affected water and sediment quality, how much the fish benefited/digested from the meal, and how much nitrogen and phosphorus remained in the fish meat and feces. Sampling was done in 2019 December, 2020 February, 2020 April, 2020 July and 2020 November. Water samples were collected from three different depth levels of these stations, and water and sediment samples were analysed by using titritmetric and spectrophometric methods. Water and sediment samples statistical analyses were made with the statistical package program SPSS 22.0 using the generalized linear model. The study was examined with three factors (station, depth, and periodical) in these analyses, and the model correlations were interpreted. In this respect, the water temperature averages 11,035,77 C; pH average values 8,260,40, dissolved oxygen values 10,73,02 mg/L; turbidity 1,260,61 m; nitrite 0,270,25 mg/L; ammonium nitrogen 0,690,84 mg/L; total nitrogen 0,910,61 mg/L; total phosphorus 0,070,08 mg/L; orthophosphate 0,0170,01 mg/L; chlorophyll-a 1,271,15 mg/m3; trix index 1,650,69; nitrogen in the sediment 0,250,12%; phosphorus in the sediment was found 0,120,11%. No difference determined between winter and spring seasons by means of digestibility rate. Total production was 350 tons, and the feed conversion ratio was calculated as 1,1. The lake's regeneration rate was 16.14. The carrying capacity was calculated to be 1184 tons based on the values of the active production period approximately three times the current production. It has been determined that production can be increased if each period is controlled and cages are rotated.