Uptake and distribution of metals in two dominant salt marsh macrophytes, Spartina alterniflora (cordgrass) and Phragmites australis (common reed)

Uptake and distribution of N, P and heavy metals in three dominant salt marsh macrophytes from Yangtze River estuary, China

“…Then the plants started to senesce , transferring a large portion of the aboveground biomass to the belowground organs. Similar seasonal variation patterns are documented in previous studies (Asaeda, Nam, & Hietz, 2002;Windham et al, 2003). Compared with Windham's results, we found an equivalent maximal aboveground biomass of P. australis (1246 g DW /m 2 in Dongtan vs. 1117 g DW/m 2 in Hackensack), though under a Mediterranean climate, the peak of aboveground biomass in P.…”

“…When marsh sediment accumulates high concentrations of nutrients and metals, macrophyte roots can absorb these materials and translocate them to aboveground biomass, which may lead to the increase of nutrient and metal bioavailability in the salt marsh (Windham, Weis, & Weis, 2003;Windham, 1999). Macrophytes in salt marshes are widely believed to decrease the rate of tidal flow, cause suspended particulate matter to sediment, enhance the retention rates of nutrients and metals from overlying water, and reduce the import of nutrients and metals to estuarine waters (Cacador, Vale, & Catarino, 2000;Daehler & Strong, 1996;Windham et al, 2003;Windham, 1999). Therefore, salt marshes are often considered efficient sinks for nutrients and metals; they can ameliorate the environmental quality in coastal ecosystem (Romero, Comin, & Garcia, 1999;Coelho, Flindt, & Jensen, 2004;Zhang, Yu, Hutchinson, Xu, Chen, & Gao, 2001).…”

“…Metal dynamics in salt marshes may be influenced by the composition of plant communities (Williams, 2002;Windham et al, 2003). Recent investigations demonstrate that concentrations of metals in plant tissues are highly variable between species (Fitzgerald, Caffrey, Nesaratnam, & McLoughlin, 2003;Ye, Baker, Wong, & Willis, 1997).…”

“…Recent investigations demonstrate that concentrations of metals in plant tissues are highly variable between species (Fitzgerald, Caffrey, Nesaratnam, & McLoughlin, 2003;Ye, Baker, Wong, & Willis, 1997). Differences in uptake rates and allocation patterns between species can generate different rates of metal retention in salt marsh vegetation and perhaps further influence the biogeochemistry of salt marshes (Windham et al, 2003;Burke, Weis, & Weis, 2000;Weis & Weis, 2004;Ornes, Sajwan, Loganathan, & Chetty, 1998 australis expansion could alter edaphic conditions (Windham & Lathrop, 1999;Bart & Hartman, 2000), accelerate nutrient cycling (Windham, 1999;Meyerson, Saltonstall, Windham, Kiviat, & Findlay, 2000), and increase metal bioavailability (Weis & Weis, 2004;Windham et al, 2003). The genus Spartina is native to the Atlantic and Gulf Coasts of North America, but it has been introduced to many coastal and estuarine regions of the world (Daehler & Strong, 1996;Chen, Li, Zhong, & Chen, 2004 (Daehler & Strong, 1996;Levin, Neira, & Grosholz, 2006).…”

Temporal variations and bioaccumulation of heavy metals in different Suaeda salsa marshes of the Yellow River estuary, China

“…With the indicator strategy, uptake and transport to shoots are passively regulated so that tissue concentrations are proportional to environmental concentration. With the accumulator strategy, metals are actively concentrated in plant tissues, reflecting a highly specialized physiology (Windham et al 2003). In this study, the allocation ratios of Cr, Ni, and Pb in roots and stems decreased during the growing season, while those in litters increased.…”