Сибирский федеральный университет

Тип публикации: статья из журнала

Год издания: 2022

Идентификатор DOI: 10.3390/w14091468

Ключевые слова: bottom-up control, eutrophication, food web, phytoplankton, saline lakes, top-down effects, zooplankton

Аннотация: Many continental saline lakes are under the effects of salinity increase and anthropogenic eutrophication exacerbated by global change. The response of the food web to these drivers of change is not straightforward. To understand the consequences of salinity and eutrophication interactive effects on the food web, we studied the seasonal dynamics of zooplankton and phytoplankton and water quality parameters in 20 lakes of different salinity (from freshwater to hypersaline) and nutrient status (from oligotrophic to eutrophic) located in southern Siberia. We observed a pro-nounced bottom-up effect of nutrients, which induced an increase in the biomass of phytoplankton and zooplankton and a decline in water quality. A significant decrease in the species abundance of zooplankton was observed at a threshold salinity of 3 g L−1 and the disappearance of fish at 10 g L−1. The top-down effect induced by salinity manifested itself in an increase in the biomass of zooplank-ton with the disappearance of fish, and in the change of the size distribution of phytoplankton particles with an increase in the proportion of cladocerans in the zooplankton. Even though we observed that with the salinity increase the food web in saline lakes transformed from three-trophic to two-trophic without fish, we conclude that in the salinity range from 10 to 20–30 g L−1 this tran-sition in most cases will not increase the ability of zooplankton to control phytoplankton. Interactive effects of salinity and eutrophication strongly depend on the size and depth of the lake, as deep stratified lakes tend to have a better water quality with lower biomasses of both phyto-and zoo-plankton. Thus, the salinity per se is not the driver of the decline in water clarity or the uncontrolled development of phytoplankton. Moreover, for deep lakes, salinity may be a factor affecting the stability of stratification, which mitigates the consequences of eutrophication. Thus, small shallow lakes will be the most vulnerable to the joint effect of salinity increase and eutrophication with the degradation of ecosystem functioning and water quality at moderate salinities of 3–20 g L−1. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

Журнал: Water (Switzerland)

Выпуск журнала: Vol. 14, Is. 9

Номера страниц: 1468

ISSN журнала: 20734441

Издатель: MDPI

• Zadereev E. (Krasnoyarsk Research Center, Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation, Insitute of Fundamental Biology and Biotechnology, Siberian Federal University, 79 Svobodniy Ave, Krasnoyarsk, 660041, Russian Federation)
• Drobotov A. (Krasnoyarsk Research Center, Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation)
• Anishchenko O. (Krasnoyarsk Research Center, Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation)
• Kolmakova A. (Krasnoyarsk Research Center, Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation)
• Lopatina T. (Krasnoyarsk Research Center, Institute of Biophysics, Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation)
• Oskina N. (Khakassky State Nature Reserve, PO Box 189, Abakan, 655017, Russian Federation)
• Tolomeev A. (Krasnoyarsk Research Center, Institute of Biophysics; Siberian Branch of Russian Academy of Sciences, Akademgorodok, Krasnoyarsk, 660036, Russian Federation, Insitute of Fundamental Biology and Biotechnology, Siberian Federal University, 79 Svobodniy Ave, Krasnoyarsk, 660041, Russian Federation)

• Scopus