Coastal Geographic Environment Analysis

There are six different types of water erosion: splash erosion, sheet erosion, rill erosion, gully erosion, valley or stream erosion, and bank erosion. Splash erosion is when raindrops hit soil and small soil particles are displaced. Sheet erosion is when raindrops remove soil in thin layers. During rill erosion, small concentrated flow paths are created. “These paths create a sediment source and delivery system for hillslope erosion. Areas where precipitation rates exceed soil infiltration rates are more prone to this type of erosion. During gully erosion, water flows in narrow channels during or after heavy rains or melting snow. The gullies can erode to considerable depths. Valley or stream erosion is created by water flowing alongside land. It extends downward, deepening a valley, and extending the valley into the hillside. This occurs more frequently

The Effects of Human Activity on Coastal Landforms Human activities add another layer of complexity to the natural processes of coastal lands and materials. These activities may have direct or indirect effects on our changing coastlines. They may effect sources of new sediment to the coast and the movement of sediment within the coastal environment. Sediment starvation caused by river and coastal management is one effect of human activities on the coast. For some coastal regions, such as the Pacific coast, a large part of their sediment is supplied by rivers.

Longshore drift is movement of sediment along the coastline. The prevailing wind blows waves carrying sediment into the beach at an angle, the waves break on the shore and as the water runs back into the sea it carries the sediment back down the beach, perpendicular to the angle. This will lead to a zigzag motion (/\/\/\/\/) as

At Nudgee Beach, erosion was found to have occurred on the edges of the mangrove forest and along the mudflat shorelines. Erosion is typically influenced by natural factors and occurs when pieces of weathered rock or soil are moved – typically by wind and water – from one place to another. Shorelines with lots of sediment and sand are more inclined to be effected by erosional progression. Erosion may also be provoked and accelerated by human interference. For example, if the decision to clear trees and plants from an area is made, erosion is likely to occur as the root systems of plants work to hold the soil in place. If these root systems are removed and erosion does occur, environmental conditions – such as; landslides and flooding – are more likely to take place. Erosion may also cause other plants to tip over, have their underground roots exposed and damaged and contribute to the pollution of local waters; as a result of mud and soil runoff [26]. Erosion at Nudgee Beach was likely to have been influenced by natural factors; however, the development and extension of the Kedron Brook golfing course may contribute to the acceleration of erosional processes and further damage the mangrove

Any rainfall increases fluvial erosion. When rain does fall, this creates ephemeral streams causing water erosion due to fast forces of water. Flash floods are possible as well creating even more erosion.

period of time have increased the size of the beach. Enviromental organisations have tried there best to limit the amount of man made deveoplment on coastal lads and many schools

Erosion is mainly caused by two main natural forces: water and wind. In Southwest Louisiana, erosion by water is one of the main issues we have as a coastal state. There are different factors that must be considered when looking at water erosion

Characterizing the morphology of the alluvial fan with the 1-meter DEM will help to further delineate the evolution of the fan. Two profiles of the alluvial fan were analyzed by creating traces along the alluvial fan seen in figure 3b and figure 3c. The elevation of figure 3b and figure 3c was traced with ArcGIS and calculated using MatLab. The cross-sections of the alluvial fan show the curvature of the fan morphology. These traces align in the west - east direction shown in figure 3b that corresponds to the profile of figure 11. Figure 3c alignment is in the north - south direction and corresponds to profile figure 12. Where the traces end, it marks the change of the slope profile of the fan. It is difficult to see but the cross-section from a to g starts out convex to concave retrospectivity. According to Stock J.D. (2008) how sediments are transported; longer profiles are commonly concave up and the shorter fans are generally convex. In contrast, the cross-sections of figure 9 show how the sediments are dispersed. There is higher density of material in profile A and has a slight convex morphology. As you move towards profile G a slight concave morphology can be

meters of vertical loss. Waves than eroded the face of the dunes that caused dune

As a wave moves into shallow water, the friction created from the wave rubbing against the ocean floor causes the crest of the wave to curl forward. The crest continues to curl forward, until the wave crashes onto the shore.

8. What are different ways that earth materials are moved around in the oceans? Surf is a powerful force. It causes erosion and moves sediment from one location to another. Currents are another manner in which materials are transported through the ocean system. There is a longshore current and a beach drift responsible for disturbing and transporting materials.

The erosion of shorelines is a natural process that can have beneficial or adverse impacts on the creation and maintenance of habitats. Sands and gravels eroded from the shores of coastal bays maintain the beach as a natural barrier between the open water and coastal wetlands. Beaches move back and forth onshore, offshore and along shore with changing wave conditions. The finer-grained silts and clays derived from the erosion of shorelines are sorted and carried as far as the waters of wetlands or tidal flats, where benefits are derived from addition of the new material. However, excessively high sediment loads can smother submerged aquatic vegetation beds, cover shellfish beds and tidal flats, fill in riffle

The weather also has a large influence. Often there are winter storm surges producing higher waves, and higher sea levels, meaning higher energy erosion. In addition is increased sub-aerial denudation brought about by the heavy rain and strong winds. This often leads to increased slumping and

The wave normals were closer at the rocky point, indicating that wave energy was higher in that location. If we take into account only wave energy, this location should have the highest rate of erosion. The difference between the wave normals in the idealized rocky point and the wave normals in the field is the direction of the approaching waves. In the field, the waves were approached the coastline at an angle from the south. In the idealized rocky point, the waves direction of approach is parallel to the coastline. As a result, the wave normals in the field had a greater curvature in the left side than in the right side.

Alongside with wind, waves are the most significant forces for sediment erosion and conveyance to the coastal zone. Wave carries a strong energy and series of current that able to transport the sediment along the shore. There are two type; longshore drift and cross-shore transport.