Relationships between fisheries, foodweb structure, and detrital pathway in a large shallow lake
Laen...
Kuupäev
2018
Kättesaadav alates
Ajakirja pealkiri
Ajakirja ISSN
Köite pealkiri
Kirjastaja
Springer
Abstrakt
We modeled energy transfer and trophic
position of fish, plankton, and macroinvertebrates and
the relative importance of top-down versus bottom-up
processes in Lake Võrtsjärv, a large shallow eutrophic
lake in Estonia (northeastern Europe). We employed
input values based on 37 years of biomass and fishing
activity monitoring for calibrating the Ecopath with
Ecosim (EwE) model. Energy flows from primary
producers and detritus, represented by total system
throughput, were nearly equal (51 and 49%, respec-
tively). Simulation revealed that top-down and bot-
tom-up forces were at play, metazooplankton was not
efficiently grazing phytoplankton production, and a
trophic cascade proceeded through macroinverte-
brates rather than through zooplankton. Detritivory
was responsible for the relatively low trophic position
of Võrtsjärv fish compared to other lakes. Bottom-up
processes were the main drivers for the dual, primary production- and detritus-based pathways in energy
flow. Our findings suggest that the predicted biomass
increase of cyanobacteria in shallow lakes in the future
will strengthen the reliance of consumers on the
detrital pathway at the expense of the primary
production pathway.
This research was supported by the Start-Up Personal Research Grant PUT 777 to FC and UB, by IUT 21-2 of the Estonian Ministry of Education and Research, and by MARS project (Managing Aquatic ecosystems and water Resources under multiple Stress) funded under the 7th EU Framework Programme, Theme 6 (Environment including Climate Change), Contract No.: 603378 (http://www.mars-project.eu).
This research was supported by the Start-Up Personal Research Grant PUT 777 to FC and UB, by IUT 21-2 of the Estonian Ministry of Education and Research, and by MARS project (Managing Aquatic ecosystems and water Resources under multiple Stress) funded under the 7th EU Framework Programme, Theme 6 (Environment including Climate Change), Contract No.: 603378 (http://www.mars-project.eu).
Kirjeldus
Märksõnad
Ecopath model, detritus, piscivorous fish, bottom-up, trophic cascade, Cyanobacteria, articles