Estimation of local environmental condition and holding density in rainbow trout cage culture (Karaova Dam Lake, Turkey)

• Main Authors: Doğukan Kaya, Serap Pulatsü
• Format: Article
• Language: English
• Published: Ege University 2016-11-01
• Series: Su Ürünleri Dergisi
• Subjects: sediment; kafeslerde balık yetiştiriciliği; gökkuşağı alabalığı; taşıma yoğunluğu; cage culture; rainbow trout; holding density
• Online Access: https://dergipark.org.tr/tr/pub/egejfas/issue/25392/268563

In this study, local environmental condition (impact) of rainbow trout (Oncorhynchus mykiss Walbaum,1792) cage farm with nearly 274 tons of total production capacity using the B-investigation of the MOM (Modelling-Ongrowing fish farms- Monitoring) system in Karaova Dam Lake (Kırsehir) was determined.  For this purpose, sediment samples, which were taken from cage bottom in October (2015) and April (2016), were evaluated based on three groups of parameters -biological (macrofauna presence: Group 1), chemical (pH and redox potential: Group 2) and sensory (outgassing, colour, odour, consistency, thickness of deposits : Group 3). Moreover holding capacity of the cages was estimated using two different oxygen-based models. Benthic macrofauna were not found in all sediment samples for cage farm. The result suggested that benthic environment of the cage farm is an "unacceptable" condition. The sediment conditions according to the chemical parameters were detemined as "transition area". According to sensory parameters, the local environmental condition of cage farm was evaluated as "partially acceptable". Therefore, it is concluded that the possible negative effects of the cage culture activities on the benthic environment will increase over the long-term because of the results of environmental quality parameters of sediment. Holding capacity in the cage farm was assessed as 0.64 kg m-3 in October (2015) and 3.71 kg m-3 in April (2016) according to Beveridge (1984) Model. In addition, using Tookwinas et al. Model  (2004), holding capacity was found as 10.91 kg m-3 and 72.47 kg m-3 in October (2015) and April (2016), respectively. As a result, oxygen-based models did not indicate appropriate results for the orientation of cage culture activities. However, the fast and easily applicable parameters, proposed in the scope of present research, are thought to be used effectively in management of cage farms with different capacities and monitoring of the environmental impacts of fish farming in inland waters.