Seasonal changes in height, biomass and biomass allocation of two exotic aquatic plants in a shallow eutrophic lake

摘要

The two exotic species, Eichhornia crassipes (Mart.) Solms and Alternanthera philoxeroides (Mart.) Griseb., are floating aquatic plants that cause serious problems throughout the world. The community establishment of these two aquatic plants and seasonal variations in Lake Donghu were studied during 1996 and 1998. The peak plant height and the maximum biomass of E. crassipes occurred in October and November respectively, whereas these peaks occurred respectively in September and November for A. philoxeroides. The variation of mat thickness of A. philoxeroides was not as intense as plant height. The biomass allocation of these species was also evaluated in 1997.