Effect of increased water depth on growth of a common perennial freshwater-intermediate marsh species in Coastal Louisiana

Abstract

The response of Sagittaria lancifolia to increased water depths of 7.5 and 15 cm was examined in this field study. Water-depth treatments were achieved by digging sods containing one or two individual plants or ramets of S. lancifolia from the marsh, removing sediment from the resulting hole, and replacing the sods in their original location at the appropriate lower elevation. Plants subjected to increased water depth of 15 cm had higher mean and maximum leaf heights than disturbed control plants. Aboveground biomass was not affected by water-depth treatment; however, 15-cm treatment plants had reduced root biomass and lowered leaf tissue concentrations of Ca, Cu, Fe, Mg, and Zn. Marsh sods at 15 cm below the marsh surface had the lowest redox potential and highest interstitial water sulfide concentration, indicating that this treatment created the most stressful belowground environment. Sagittaria lancifolia plants responded to the level of stress imposed by the experimental conditions with an altered growth form of increased leaf height.

A Landscape-Scale Assessment of Above- and Belowground Primary Production in Coastal Wetlands: Implications for Climate Change-Induced Community Shifts

“…In this study, trends in belowground production reflected trends in total production, which declined from years 1 to 2; however, aboveground production remained constant over time. The observed inter-annual variation of belowground production may be an example of translocation in response to changing resource limitations (Bloom et al 1985;Chapin et al 1993;Shipley and Meziane 2002) resulting in consistent aboveground production rates over time (Howard and Mendelssohn 1995). This implies that ecosystem-level responses to changes in environmental parameters will be more apparent in belowground biomass dynamics compared with aboveground biomass dynamics, and that belowground production is a better indicator of ecosystem health than aboveground production (Turner et al 2004).…”

“…However, when stressful conditions extend beyond a plant's zone of tolerance, or adaptive ability, belowground biomass production will eventually decline (Mendelssohn and Seneca 1980;Bandyopadhyay et al 1993;Howard and Mendelssohn 1995;Brown et al 2006). In the current study, belowground production declined from year 1 (2012-2013) to year 2 (2013-2014).…”

The Effects of Flooding on Four Common Louisiana Marsh Plants

“…Howard and Mendelssohn (1995) lowered Sagittaria lancifolia marsh sods by 7.5 cm and 15 cm, which resulted in a linear decrease in the average soil redox at 2 cm below the marsh surface. Sagittaria lancifolia response with decreased elevation included an increase in mean height, no effect on aboveground biomass, and no effect on total belowground biomass (roots and rhizomes), although root biomass decreased.…”

Análise morfológica de Sagittaria montevidensis desenvolvida em diferentes condições de inundação

“…Resposta similar foi observada em Sagittaria lancifolia, que apresentou tolerância à submersão e não teve sua biomassa alterada pela profundidade da lâmina d'água (Howard & Mendelssohn, 1995). Da mesma forma, não foi verificada alteração de biomassa subterrânea em S. latifolia e S. platyphylla, quando expostas à profundidade de 30 cm de água (Martin & Shaffer, 2005).…”

“…S. sagittifolia tolerou submersão prolongada por oito semanas, através do aumento do comprimento da parte aérea (van den Brink et al, 1995). S. lancifolia respondeu à elevação do ní-vel d'água em 7,5 e 15 cm por meio do aumento da altura da folha (Howard & Mendelssohn, 1995). Quando em condições anaeróbias, S. pygmaea apresentou crescimento da parte aé-rea, através do alongamento celular, promovido pela ação do cálcio (Tamura et al, 2001).…”