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Extrinsic vs. Intrinsic Regimes Shifts in Shallow Lakes: Long-Term Response of Cyanobacterial Blooms to Historical Catchment Phosphorus Loading and Climate Warming

“…Other environmental variables could also have influenced the cyanobacterial concentration in shallow lakes and the shift from a clear-water to a turbid-water state (Scheffer and van Nes, 2007). For example, perturbations such as large storm events damaging macrophyte beds (Bachmann et al, 1999) have been linked to a regime shift in Lake Apopka in Florida, although others have disputed this interpretation arguing instead that extensive phosphorus export from the catchment was the primary driver of excessive algae growth in this lake (Lowe et al, 2001). We cannot dismiss the role of other potential perturbations in triggering the nonlinear increase in cyanobacteria in these lakes, however, greater phosphorus inputs and warming temperatures remain dominant and overarching drivers of increased cyanobacterial concentrations in temperate lakes across the globe (Downing et al, 2001;Taranu et al, 2015).…”

Pondweeds of Florida

“…Illinois pondweed is present across numerous nutrient-rich lakes in Florida (Hoyer et al 1996). While this species is tolerant of moderately high-nutrient environments, excess nutrient loading (particularly phosphorus) has contributed to its decline in some lakes, such as Lake Apopka (Lowe et al 2001). Leaf Characteristics: Has both floating and submersed leaves.…”

A blooming business : Identifying limits to Lake Taihu's nutrient input

“…The estimated probability of other large shallow lakes to have macrophyte domination, and, if so, whether these have a potentially alternative stable state is shown in Figure 2.9a. A comparison with the model outcomes indicate that 8 lakes might have alternative stable states (Table 2.1) including Lake Apopka (USA) where literature previously presumed alternative stable states as well (Bachmann et al, 1999;Lowe et al, 2001). The majority of the other lakes that are indicated by the model to potentially have alternative stable states are reported to support macrophytes, which in some lakes became too excessive, resulting in problems with boating access and flooding as in Lake Guiers (Senegal) (Cogels et al, 1997;Hellsten et al, 1999) and Loktak (India) (Singh et al, 2011).…”

“…Apopka USA 28°37'N, 81°37'W 125 1.7 4.6 15.7 ASS The entire lake shifted from macrophyte to phytoplankton dominance triggered by a hurricane, after long-term eutrophication (Bachmann et al, 1999;Bachmann et al, 2001;Lowe et al, 2001). 5…”

“…But there are also larger lakes with macrophytes and where alternative stable states are presumed. For example, Lake Apopka (125 km 2 ) in the USA became susceptible to disturbances due to increasing nutrient loading; the large macrophyte stands finally disappeared after a disruptive hurricane event (Bachmann et al, 1999;Lowe et al, 2001).…”