| Popis: |
This study aims to identify proper solutions that can improve the sustainability of cyprinids pond aquaculture in terms of nitrogen releases to the environment. Therefore, two experimental variants, based on polyculture, respectively integrated multi-trophic aquaculture (IMTA) concept were tested, as follows: PCP – polyculture of common carp (CC) + grass carp (GC) + bighead carp (BC) + silver carp (SC); CP-PP – net divided pond with CC monoculture in CP part and CC+GC+BC+SC polyculture in PP part. In order to determine the nitrogen accumulation at the pond level, samples of water, sediments, fish meat and reed were analyzed. The results indicate that the highest nitrogen compounds concentrations in pond water were registered at CP part of CP-PP pond. However, the nitrogen concentration in pond effluents was significant higher in case of CP-PP pond, compared with PCP pond. The nitrogen compounds concentration of sediments registered the highest values in the ponds outlet area. Also, CP-PP pond recorded higher nitrogen concentration in sediments, compared with PCP pond. The CC registered the highest nitrogen compounds concentration in case of PP pond area, followed by CP pond area and PCP pond. Not significant correlation was found between reed and pond water/ fish meat/ sediments in terms of nitrogen compounds concentration. It can be concluded that the CP-PP pond feeding management, together with the tested technical solution (pond dividing) generated better water conditioning performances. |
