Shallow water bodies can exist in alternative stable states,a clear water state with high coverage of maerophytes or a turbid state with high phytoplankton biomass.The alternative equilibria hypothesis has been proposed to explain the occurrence of the alternative stable states (Scheffer et al.,1993)[1],which assumes that:1),turbidity increases with the nutrient level; 2),macrophyte reduces turbidity; and 3),macrophyte disappears when a critical turbidity is exceeded.At low nutrient levels,the water should be clear,with low phytoplanlaon biomass and extensive macrophyte coverage.At high nutrient levels,the water should be turbid,with high phytoplankton biomass and a lack of macrophytes.
Shallow water bodies can exist in alternative stable states,a clear water state with high coverage of maerophytes or a turbid state with high phytoplankton biomass.The alternative equilibria hypothesis has been proposed to explain the occurrence of the alternative stable states (Scheffer et al.,1993)[1],which assumes that:1),turbidity increases with the nutrient level; 2),macrophyte reduces turbidity; and 3),macrophyte disappears when a critical turbidity is exceeded.At low nutrient levels,the water should be clear,with low phytoplanlaon biomass and extensive macrophyte coverage.At high nutrient levels,the water should be turbid,with high phytoplankton biomass and a lack of macrophytes.
QIU Jian-Wen. Wetland macrophyte diversity, trophic status and phytoplankton:a case study of the cascading effects of an invasive herbivore[J]. , 2008, 27(5): 310-314.
QIU Jian-Wen. Wetland macrophyte diversity, trophic status and phytoplankton:a case study of the cascading effects of an invasive herbivore. , 2008, 27(5): 310-314.
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