“…Thus, several species of Spartina, such as S. alterniflora or S. maritima, show clearly distinguishable tall and short growth forms (Shea et al, 1975;Mendelssohn, 1979;Anderson & Treshow, 1980;Howes et al, 1986;Pezeshki & DeLaune, 1991;Castillo et al, 2005a). Some studies have concluded that the observed variability in growth forms among Spartina populations may be the result of genetic differentiation (Gallagher et al, 1988;Sanchez et al, 1997;Proffitt et al, 2003), identifying ecotypes with different canopy heights and biomass accumulation (Lessmann et al, 1997;Daehler, 1999;Otero et al, 2000;Seliskar et al, 2002;Proffitt et al, 2005). In contrast, other studies have attributed different growth forms to phenotypic plasticity in response to differences in environmental factors (Anderson & Treshow, 1980), such as the availability of nutrients (Dai & Wiegert, 1997;Wigand et al, 2003;Zhao et al, 2010), salinity (Phelger et al, 1971;Trnka & Zedler, 2000) or sediment anoxia (Castillo et al, 2005a).…”