Spartina alterniflora Research Papers - Academia.edu (original) (raw)

Marshes have been proposed as sites for phytoremediation of metals. The fate of metals within plant tissues is a critical issue for effectiveness of this process. In this paper we review studies that investigate the effects of plants on... more

Marshes have been proposed as sites for phytoremediation of metals. The fate of metals within plant tissues is a critical issue for effectiveness of this process. In this paper we review studies that investigate the effects of plants on metals in wetlands. While most of these marsh plant species are similar in metal uptake patterns and in concentrating metals primarily in roots, some species retain more of their metal burden in belowground structures than other species, which redistribute a greater proportion of metals into aboveground tissues, especially leaves. Storage in roots is most beneficial for phytostabilization of the metal contaminants, which are least available when concentrated below ground. Plants may alter the speciation of metals and may also suffer toxic effects as a result of accumulating them. Metals in leaves may be excreted through salt glands and thereby returned to the marsh environment. Metal concentrations of leaf and stem litter may become enriched in metals over time, due in part to cation adsorption or to incorporation of fine particles with adsorbed metals. Several studies suggest that metals in litter are available to deposit feeders and, thus, can enter estuarine food webs. Marshes, therefore, can be sources and well as sinks for metal contaminants. Phragmites australis, an invasive species in the northeast U.S. sequesters more metals belowground than the native Spartina alterniflora, which also releases more via leaf excretion. This information is important for the siting and use of wetlands for phytoremediation as well as for marsh restoration efforts.

To understand the tolerance mechanism associated with high temperature stress in a halophyte smooth cordgrass (Spartina alterniflora), a few selected salt-induced genes including transcription factors were studied for their transcript... more

To understand the tolerance mechanism associated with high temperature stress in a halophyte smooth cordgrass (Spartina alterniflora), a few selected salt-induced genes including transcription factors were studied for their transcript abundance. The mRNA analysis of eight genes and nine transcription factors known to be involved in various salt tolerance mechanisms revealed temporal and tissue-dependent variation in their expression under high temperature stress. Differential response of genes under heat and salt stress (reported earlier) indicated different mode of action in the metabolic pathway in response to different environmental cues, and a few common genes responsive to multiple stresses showed temporal and tissue-dependent variation in their expression. This study demonstrates that S. alterniflora could be a potential source of candidate genes conferring tolerance against high temperature in addition to salt tolerance for crop improvement.

Thirty-four grass species were collected for phytolith analysis from a variety of coastal environments in the southeastern USA (Georgia, Florida, and Louisiana), including salt marshes, freshwater/brackish marshes, pine/oak forests,... more

Thirty-four grass species were collected for phytolith analysis from a variety of coastal environments in the southeastern USA (Georgia, Florida, and Louisiana), including salt marshes, freshwater/brackish marshes, pine/oak forests, maritime hardwood forests, and sand dunes. Phytoliths produced by these modern grasses include a large diversity of shapes and types. We propose a preliminary relationship between modern coastal plant communities and their predominant phytolith contents. The dominant grasses of coastal sand dunes, such as Uniola paniculata, produce primarily flat tower and two-horned tower phytoliths. Rondel/saddle ellipsoid phytoliths are mainly produced by Spartina alterniflora, the most common plant in coastal salt marshes. Rondel and spool/horned tower phytoliths are common in brackish marsh grasses. Plants from interdune meadow produce primarily dumbbell phytoliths, as well as small cross and Cyperaceae-type phytoliths. These results provide a basis for the interpretation of fossil phytolith assemblages and the reconstruction of coastal environmental changes.

The Tuckerton Peninsula forms a large expanse (~2,000 ha) of highly inundated Spartina alterniflora salt marsh habitat along the southern New Jersey coast. It comprises one of the most extensive coastal wetland systems in New Jersey, and... more

The Tuckerton Peninsula forms a large expanse (~2,000 ha) of highly inundated Spartina alterniflora salt marsh habitat along the southern New Jersey coast. It comprises one of the most extensive coastal wetland systems in New Jersey, and it is projected to be among the first of these systems in the state to be lost by rising sea level associated with climate change and shoreline erosion. Here interior marsh loss from an expanding channel network and pond development is causing significant dissection of the marsh platform. Reduction in marsh habitat area has accelerated due to perimeter shoreline erosion, sea-level rise, and coastal submergence; for example, the rate of loss of salt marsh habitat along the eastern and southern shorelines of the south segment amounted to 1.6 m yr-1 between 1995 and 2008. Current sediment accretion rates (0.18 to 0.30 cm yr-1) of salt marsh in the general area are only slightly higher than local rates of relative sea- level rise (0.10 to 0.24 cm yr-1), and they may be significantly lower in future years. In response to sea-level rise, submergence, and erosion, the tidal salt marshes undergo both structural and functional changes manifested by shifts in species composition, distribution, and abundance of marsh vegetation. A recent study was conducted to characterize the temporal and spatial changes in the emergent salt marsh vegetation in three segments (north, central, and south) of the peninsula as part of a larger investigation to establish this salt marsh platform as a NOAA-JCNERR sentinel site to assess future climate change effects. Monthly quadrat sampling at 90 plots along 9 transects in the peninsula during the June-September period in 2011 revealed only 7 species of marsh plants (Spartina alterniflora, S. patens, Distichlis spicata, Salicornia spp., Limonium carolinianum, Morus rubra, and Symphyotricum tenuifolium). Measurements collected on maximum canopy height, shoot/stem density, and areal cover of the marsh plant community in the heavily ditched north segment were compared to those of the marsh plant communities in the shoreline-altered south segment and the less impacted central segment. Changes occurring in the demographic and ecological characteristics of the emergent salt marsh habitat at this location will be vital to understanding future habitat change in coastal wetlands of New Jersey, the Mid-Atlantic region, and the entire East Coast of the US.

Perennial monoculture forming grasses are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential.... more

Perennial monoculture forming grasses are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential. Transfer of key genes for mercury phytoremediation into the salt marsh cordgrass (Spartina alterniflora) is reported here. S. alterniflora plays an important role in the salt marsh by cycling of elements, both nutrients and pollutants, protects the coastline from erosion, is a keystone species in the salt marsh supporting a large food web, which in turn supports a significant segment of economy, including tourism, has an impact on cloud formation and consequently on global weather, and is thus an ecologically important species relevant for our life-support systems. Embryogenic callus of S. alterniflora was co-inoculated with a pair of Agrobacterium strains LBA4404 carrying the organomercurial lyase (merB) and mercuric reductase (merA) genes, respectively, in order to co-introduce both the merA and the merB genes. Seven stable geneticin resistant lines were recovered. The presence of merA and merB genes was verified by PCR and Southern blotting. All but one transgenic lines contained both the merA and the merB sequences proving that co-introduction into Spartina of two genes from separate Agrobacterium strains is feasible and frequent, although the overall frequency of transformation is low. Northern blotting showed differences in relative expression of the two transgenes among individual transformants. The steady-state RNA levels appeared to correlate with the phenotype. Line #7 showed the highest resistance to HgCl(2) (up to 500 microM), whereas line #3 was the most resistant to phenylmercuric acetate (PMA). Wild-type (WT) callus is sensitive to PMA at 50 microM and to HgCl(2) at 225 microM.

We report the occurrence of the orange-striped green anemone Diadumene lineata (Verrill 1871) (=Haliplanella lineata) in salt marshes at the Bahía Blanca Estuary for the first time in August 2005. We also found this species attached to... more

We report the occurrence of the orange-striped green anemone Diadumene lineata (Verrill 1871) (=Haliplanella lineata) in salt marshes at the Bahía Blanca Estuary for the first time in August 2005. We also found this species attached to roots and stems of Spartina alterniflora, an association that has never been registered before. After their determination, sampling was performed during a year to evaluate seasonal abundance of this sea anemone. Results showed that D. lineata was present through the whole year, indicating the existence of a stable population. All individuals sampled were found attached to roots or stems of S. alterniflora, with the higher abundances detected in summer. Further studies are necessary to precise the potential effects of this exotic sea anemone on salt marsh communities.

In order to examine the role of position in the tidal range on biomass production and nutrient pools in Spartina alterniflora in an Argentinian estuary, we estimated productivity, the concentration of C, N and P in tissues and pools... more

In order to examine the role of position in the tidal range on biomass production and nutrient pools in Spartina alterniflora in an Argentinian estuary, we estimated productivity, the concentration of C, N and P in tissues and pools (concentration × biomass) of these elements in low (LM) and high (HM) zones.
Aboveground biomass of S. alterniflora was higher in HM than in LM. Aboveground primary productivity was 106 and 439 g dry wtm−2 year−1 in LM and HM, respectively. Belowground biomass was similar in LM and HM. Belowground primary productivity was 526 and 744 g dry wtm−2 year−1 for LM and HM, respectively. Nutrient pools were higher in HM than in LM. Biomass and productivity values were low, which makes nutrient pools low. The lower values of the parameters analysed in LM than in HM indicate that position in the tidal range is an important factor in this system, possibly due to the effect of flooding.
Moreover, this pattern is opposite to the general one observed in the northern hemisphere, meaning that studying marshes from different environments is worth doing. Because pools were higher in HM, this zone would be more important for nutrient input to the estuary.

Perennial monoculture forming grasses are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential.... more

Perennial monoculture forming grasses are very important natural remediators of pollutants. Their genetic improvement is an important task because introduction of key transgenes can dramatically improve their remediation potential. Transfer of key genes for mercury phytoremediation into the salt marsh cordgrass (Spartina alterniflora) is reported here. S. alterniflora plays an important role in the salt marsh by cycling of␣elements, both nutrients and pollutants, protects the coastline from erosion, is a keystone species in the␣salt marsh supporting a large food web, which in turn supports a significant segment of economy, including tourism, has an impact on cloud formation and consequently on global weather, and is thus an ecologically important species relevant for our life-support systems. Embryogenic callus of S. alterniflora was co-inoculated with a pair of Agrobacterium strains LBA4404 carrying the organomercurial lyase (merB) and mercuric reductase (merA) genes, respectively, in order to co-introduce both the merA and the merB genes. Seven stable geneticin resistant lines were recovered. The presence of merA and merB genes was verified by PCR and Southern blotting. All but one transgenic lines contained both the merA and the merB sequences proving that co-introduction into Spartina of two genes from separate Agrobacterium strains is feasible and frequent, although the overall frequency of transformation is low. Northern blotting showed differences in relative expression of the two transgenes among individual transformants. The steady-state RNA levels appeared to correlate with the phenotype. Line #7 showed the highest resistance to HgCl2 (up to 500 μM), whereas line #3 was the most resistant to phenylmercuric acetate (PMA). Wild-type (WT) callus is sensitive to PMA at 50 μM and to HgCl2 at 225 μM.

The effect of No. 2 fuel oil on the biomass production of the salt marsh plant, Spartina alterniflora, was studied in a greenhouse dose-response experiment. S. alterniflora were transplanted into soil with 10 dosage levels of No. 2 fuel... more

The effect of No. 2 fuel oil on the biomass production of the salt marsh plant, Spartina alterniflora, was studied in a greenhouse dose-response experiment. S. alterniflora were transplanted into soil with 10 dosage levels of No. 2 fuel oil ranging from 0 to 456 mg g(-1) dry soil. Three months after transplantation, values for plant biomass, stem density, and shoot height decreased significantly with increasing fuel oil level in a dose-response fashion. Evapo-transpiration rates were correlated with the total biomass response. Relative to the control, a significant decrease in total (above- plus below-ground) plant biomass was observed at concentrations above 57 mg g(-1) dry soil. Within the 3-month experimental period, detrimental effects on below-ground biomass accumulation and bioluminescence of the marine bacterium Viberio fisheri in the Microtox Solid Phase Test were observed at oil concentrations >29 mg g(-1) dry soil, suggesting that biological effects of oil within the se...

Suspended sediments in tidal creeks and sediments deposited on the adjacent marsh surface, collected concurrently at Mud Bank (MB) and Sixty Bass (SB) in North Inlet, SC from March, 1991 until February, 1992 were compared. For 8... more

Suspended sediments in tidal creeks and sediments deposited on the adjacent marsh surface, collected concurrently at Mud Bank (MB) and Sixty Bass (SB) in North Inlet, SC from March, 1991 until February, 1992 were compared. For 8 consecutive days of each lunar month (waxing moon neap tide until full moon spring tide), sediment traps collected daily and water pumped from the adjacent creek at 3.1 hour intervals (mid-flood, high tide, and mid-ebb) were analyzed for inorganic and organic sediment, as well as carbon and nitrogen content. Salinity, sea level, Pee Dee River discharge, rainfall, temperature, wind, and inundation time were examined as forcing functions. SB creek connects to the oceanic inlet, but MB is located near the tidal node where brackish and high salinity waters meet in a sharp halocline. Although the duration of inundation is approximately twice as long as SB (12.5 hr/d:7.4 hr/d) because of a 27 cm elevation difference. MB averaged more deposition (5.3 mg/d/cm 2 : 4....