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The adaptations of salt marsh plants in response to the environmental conditions they encounter The adaptations of salt marsh plants in relation to the environmental conditions they face within the salt marsh community were observed and recorded. Soil conditions and faunal presence was also noted. The study was carried out in Westernport Bay at a salt marsh near Hastings in Victoria. A transect was run across the salt marsh with 2 metre by 2 metre quadrats placed 15 metres apart. It was found that Avicennia marina (Forssk, Vierh) grew from 0 -15 metres while the growth of the other 9 species studied varied in response to the various environmental conditions. Salinity and field moisture content were large determining factors of their distribution. The adaptations that enabled the plants to survive within the salt marsh varied between species. Introduction Victorian salt marshes are highly diverse communities (Ross, 2000) that are dominated by herbs and low shrubs (Adam, 2000) with Sclerostegia arbuscula (Wilson, Paul G.) and sarcocornia quinqueflora (Scott, A.J.) being the largely dominant species (Ross, 2000). Two other coastal communities that are regularly associated with salt marshes are mangroves and seagrasses (Gibson M., 2003). These communities generally occur parallel to the shore (Ross, 2000) and vary in their degree of exposure in accordance to the tides (Gibson M., 2003). Salt marshes are prone to periods of flooding due to changes in the levels of nearby water bodies (Gibson M., 2003). Only one species of mangrove grows in Victoria, A. marina (Ross, 2003), which is probably due to being able to survive at lower temperatures (Hutchings, 1987). Generally there is a clear distinction between the mangroves and the slat marshes (Adam, 2000), where the mangroves are dominated by trees up to thirty metres tall and are located in the upper intertidal regions (Gibson M., 2003). In Victoria, this distinction is hazy as the stunted mangroves are lower in height than S. arbuscula, the tallest salt marsh shrubs (Adam, 2000). Saltmarshes and seagrasses are identified on the grounds of floristics and physiognomy as there is also at times an intermingling of the uppermost seagrasses and lowest salt marshes (Adam, 2000). Hastings salt marsh is located in the Westernport Bay in Victoria. Westernport Bay’s biota has greater diversity than any other inlet in Victoria (Ross, 2000). Salt marshes are highly important ecosystems that have been damaged because of a number of factors. Very few studies have been conducted in the last 25 years and so very little is known still about how salt marshes function. This report will discuss the adaptations of local flora in relation to the environmental conditions that they face within the salt marsh. Within this broad area, factors such as changes in salinity, pH and nature of the soil will be examined in accordance to these adaptions along with faunal visitation and/or presence. Method The salt marsh visited was at the end of Yaringa road near Hastings (Fig. 1). The landward margin of the salt marsh was boarded by a scrub of tea trees and eucalypt (Melaleuca ericifolia (Andrews, H.C.) and Eucalyptus viminalis (Hooker, W.J.) respectively). The seaward boarder was dominated by the mangrove species A. marina. A transect was run from the mangroves to the Melaleuca scrub.
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