Long‐term pattern of alternative stable states in two shallow eutrophic lakes

Abstract

1. Lake Takem and Lake Krankesjon, two moderately eutrophic, shallow lakes in southern Sweden, have during the past few decades shifted several times between a clear-water state with abundant submerged vegetation and a turbid state with high phytoplankton densities. 2. Between 1985 and 1991, Lake Takem was in a clear state, whereas Lake Krankesjon shifted from a turbid to a clear state. During this shift, the area covered by submerged macrophytes expanded, followed by an increase in water transparency, plant-associated macroinvertebrates, and piscivorous fish. Nutrient concentrations, phytoplankton biomass and abundance of planktonic cladocerans decreased. 3. In both lakes, water level fluctuations were the most common factor causing shifts, affecting submerged macrophytes either through changes in light availability or through catastrophic events such as dry-out or mechanical damage by ice movement. 4. Our data give further support for the existence of two alternative stable states in shallow lakes maintained by self-stabilizing feedback mechanisms.

Changes in physicochemical and biological factors during regime shifts in a restoration demonstration of macrophytes in a small hypereutrophic Chinese lake

“…Up to now, there is almost no evidence of successful macrophyte recovery in turbid, phytoplankton-dominated lakes, despite strong reduction of external nutrient loading in some cases (Van Liere and Janse, 1992;Coveney et al, 2002). In other studies, an extensive and dense macrophyte community developed, but was not stable in the long-term (Blindow et al, 1993;Perrow et al, 1994;Simons et al, 1994).…”

The restoration of aquatic macrophytes for improving water quality in a hypertrophic shallow lake in Hubei Province, China

“…The alternative stable states have been considered to exist in eutrophic shallow lake, so that eutrophication of the lake could be expressed in its extreme state as a switch from macrophyte dominance to phytoplankton dominance (Moss, 1990;Scheffer, 1990;Blindow et al, 1993). Similarly, these two states were formerly referred to as macrophyte type and algal type lakes in China.…”

Towards a more precisely defined macrophyte-dominated regime: the recent history of a shallow lake in Eastern Poland

“…The year-round persistence of the submerged vegetation must have been of high importance for the lake with retention of nutrients in the plant biomass, even in winter, restricting the development of phytoplankton (Scheffer, 1998). Moreover, the continuous presence of macrophytes reduces the risk of e.g., cold conditions delaying the growth of submerged macrophytes in early spring, which could favour algal development (Blindow et al, 1993;Bayley et al, 2007;Sayer et al, 2010b;Hilt et al, 2013). Year-round vegetation provides rich resources of epiphytic fauna as food for fish, reducing their pressure on zooplankton (Diehl & Kornijów, 1998;Kornijów et al, 2005Kornijów et al, , 2016.…”

“…Since the appearance of the alternative stable state concept, global research on various aspects of the functioning of shallow lakes has intensified, especially because knowledge of the subject was of key importance for lake management and restoration measures (Moss et al, 1996;Jeppesen, 1998;Scheffer, 1998;Jeppesen et al, 2007;Moss, 2007b). As a result, the concept of alternative stable states has developed, and the perception of the state generally described as macrophyte-dominated has been specified in more detail, showing that the state can be represented by the dominance of among others free-floating plants, charophytes, or submerged angiosperms (Blindow et al, 1993;Blindow et al, 2014).…”