Consumer-driven nutrient release to the water by a small omnivorous fish enhanced ramet production but reduced the growth rate of the submerged macrophyte Vallisneria denseserrulata (Makino) Makino


Yu J., Xia M., Zhao Y., He H., Guan B., Chen F., ...More

Hydrobiologia, vol.848, no.18, pp.4335-4346, 2021 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 848 Issue: 18
  • Publication Date: 2021
  • Doi Number: 10.1007/s10750-021-04643-5
  • Title of Journal : Hydrobiologia
  • Page Numbers: pp.4335-4346
  • Keywords: Ramet production, Bitterling, Fish-macrophytes interaction, Omnivore, Lake restoration, Consumer-driven nutrient recycling, CARP CARASSIUS-CARASSIUS, SHALLOW LAKE, COMMON CARP, PHOSPHORUS CONCENTRATIONS, COMMUNITY STRUCTURE, BITTERLING FISH, RESTORATION, BIOMANIPULATION, PERIPHYTON, LIGHT

Abstract

© 2021, The Author(s), under exclusive licence to Springer Nature Switzerland AG.Small fish are highly associated with submerged macrophytes but may potentially hamper their growth due to nutrient excretion that stimulate growth of phytoplankton and periphyton growth. We conducted a mesocosm experiment to elucidate the effects of the small omnivore Chinese bitterling Acheilognathus macropterus on the growth of phytoplankton, periphyton and the submerged macrophyte Vallisneria denseserrulata. The treatments were fishless as well as low (LF) and high (HF) fish density. We found that the concentrations of nutrients and the phytoplankton biomass increased substantially in both fish treatments, leading to a significantly higher light attenuation compared with the control. Moreover, bitterling substantially enhanced the biomass of periphyton on plant leaves. Consequently, the relative growth rate (RGR) of V. denseserrulata was significantly suppressed in HF, while RGR in the LF treatment did not differ significantly from the controls. However, the bitterling also stimulated the ramet production of V. denseserrulata, significantly. Our results indicate that Chinese bitterling reduce the RGR of V. denseserrulata under high fish density condition. Therefore, the density of Chinese bitterling should be kept low in order to reduce the negative effects of the fish on the RGR of submerged macrophytes (e.g. V. denseserrulata), when restoring lakes by plant transplantation.