The theoretical part of the thesis contains a literature review of the current knowledge on the occurrence and importance of aquatic invertebrates in salmonid fish farms. The practical part includes monitoring and determination of abundance, diversity and taxonomic composition of aquatic invertebrates in a recirculating system in Pravíkov. Sampling was conducted once a month during the vegetative season over three years, from 2015 to 2017. Samples were taken using an adjusted benthic net, from three sam-pling sites: bottom of the outflow canal from the breeding tanks, bottom of the inflow canal to the breeding tanks and the system’s wall. In addition to the abundance and diversity of aquatic invertebrates, the physico-chemical parameters of water were also measured. During the monitoring period, common breeding interventions were conduct-ed, including the discharge and disinfection of the entire system. During the monitoring period, a total of 36,066 individuals from 133 taxa of aquatic invertebrates were recorded. In 2016, despite the disinfection of the system, the highest number of taxa (74) and abundance (17,700) were registered. In 2016 and 2017, the vast majority of the macrozoobenthos collected were Chironomidae and Oligochaeta, which showed a significant growth in abundance in comparison with 2015. In 2015, 69 taxa with an abundance of 15,436 individuals were recorded. The cleaning of the system showed the highest effect on macrozoobenthos in 2017, when the bryophyte vegetation regrowth did not occur on the wall and some of the samples were without macrozoobenthos. Altogether, only 2,930 aquatic invertebrates and 67 taxa were detected. Values of the Shannon–Weaver index (H´) ranged from 1.335 to 2.214 in 2015, from 0.853 to 2.583 in 2016 and from 1.116 to 2.508 in 2017. Off all macrozoobenthos taxa recorded, Asellus aquaticus presents a potential danger to farmed fish, as it can be an intermediate host of Acanthocephala. This is also true for some species of molluscs, which can be intermediate hosts of trematodes.
| Identifer | oai:union.ndltd.org:nusl.cz/oai:invenio.nusl.cz:427707 |
| Date | January 2019 |
| Creators | Seifried, Jakub |
| Source Sets | Czech ETDs |
| Language | Czech |
| Detected Language | English |
| Type | info:eu-repo/semantics/masterThesis |
| Rights | info:eu-repo/semantics/restrictedAccess |
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