Point Cartwright Essay

Queensland coastal dunes are an integral part of coastal environment and ecosystems. Queensland beaches are known for a number of its natural icons and prominent features and are widely recognized and appreciated for their breath taking scenery, significant biodiversity, recreation experiences and generation of economic benefits from tourism. With the influx of human influence with beachfront development, mowing and topsoiling dunes, pedestrian and vehicular traffic, weeds and feral animals disturbing the native ecological communities, leads to the destruction of delicate sand dunes creating more damaging problems such as erosion. (reference)

Point cartwright is located on the coast of south east Queensland and stretches 100m. It has a diverse environments such as sand

dunes and rocky shores that are important for the life of all its inhabitants.
Sand dunes are formed through the combination of waves and wind patterns which causes sand to build up. These areas support and sustain plant and animal life and is vital in maintaining a healthy coast line. Stable sand dunes play a dynamic part in protecting the coastline.

They act as a shield against wave damage throughout storms, protecting the land behind from salt water intrusion. This sand barrier allows the growth of more complex plant communities in areas protected from salt water inundation, sea spray and strong winds. Communities of plants that grow on beaches and dunes are known as dune vegetation.

The ecology of these ecosystems plays a key role in mediating many of the functions of dunes, including their growth and stabilization. Similarly, the physical environment of this unique habitat strongly shapes the ecology of the organisms living there.

- explain abiotic changes that happen along a gradient and how do species change as a result.

Zonation is the categorization of biomes into zones based on their distribution or arrangement in a habitat as determined by environmental factors, e.g. altitude, latitude, temperature, other biotic factors, etc. (Collins English Dictionary, n.d.). There are three main zones of dune vegetation that are arranged roughly parallel to the coastline. Closest to the sea is the pioneer zone, extending landward from the debris line at the top of the beach in an area called the foredune or frontal dune as seen in

Table 1. In the pioneer zone of the beach where sediments are covered frequently by water, aquatic organisms thrive. However, in the areas at and just above the high tide zone, conditions are harsh. The lack of water makes life nearly impossible for aquatic or terrestrial organisms, and the dry sand is easy to heat and cool, resulting in strong swings in temperature from too hot to bitterly cold during winter (sunshine coast council, 2016. Foredune or frontal dune areas are more protected from wind, blowing sand and salt spray and this results in increased nutrients and moisture available for plant growth. Such species observed include spinifex (Spinifex sericeus), pig face (Carpobrotus glaucescens) and goat's foot convolvulus (Ipomoea pes-caprae). Weeping horsetail sheoaks (Casuarina equisetifolia) and screw pines (Pandanus tectorius) are common tree species found along the coast and were observed at the point cartwright transect (seen in table 2). All these plants have specialised characteristics that allow them to cope with the extreme conditions as seen in table 4, they have adaptations such as waxy and/or hairy coverings on their stems and leaves, narrow leaves, succulent leaves, extensive and vigorous root systems or other such traits that allow them to cope with little water and nutrients and lots of wind and salt. The array and health of plant life is vital in the strength of food chains and animals in a coastal ecosystem providing shelter and food for surrounding organisms. Organisms living in this zone must have a high tolerance for being blasted with and buried by the constantly moving sand, lack of nutrients and high salinity levels (removal, 2016) . As seen in Table 3 there was a variety of organisms that were observed in the point cartwright dunes such as ghost crabs, ants and grasshoppers.