Coastal Erosion

Coastal Erosion

The 4 components which define the biophysical environment are the biosphere, lithosphere, hydrosphere and atmosphere. These 4 spheres interact however they are changing. One such example is the coast, the fragile environment where the land meets the water. It is important to consider the spatial dimension, patterns formed where environmental factors are located and the ecological dimension, the relationship of organisms and the physical environments. Coastal erosion is a natural process that can be impacted upon by human activities. The management of coastal sediments is a very current issue because action needs to be taken to lessen the impact of human activities disrupting coastal processes.
The beach erosion-accretion cycle is a natural process of offshore/onshore sand exchange. Accretion is the accumulation of sediments such as sand from the natural action of waves, currents and wind. Erosion is the wearing away of the land, usually by the action of natural forces such as the transfer of energy with the large waves during storms. Storm waves move large quantities of sand from beach and dune to build offshore sand bars. The dunes provide a natural defence against wave attack by restricting the intrusion of waves, wind and salt spray. They also act as a reservoir for resupplying sand to a beach during storms. Offshore storm bars cause waves to break further out lessening force. Subsequent calm weather follows onshore movement of sand to re-establish the beach. Subsequent calm weather follows onshore movement of sand to re-establish a beach.  
Coastal environments are being placed under greater stress as humans have disrupted these natural processes. 70% of the NSW population live within the coastal region. To house and service this population the coast now supports resident and commercial development. Human activities can include building and construction and disposal of sewerage and storm water. Parallel dunes are often flattened and built over and the fore...