The Process Of Coastal Erosion Environmental Sciences Essay

Coastal erosion is a natural process in which sand and rocks are dislodged from the shoreline by various eroding agents. Wave erosion is one of the major eroding agents which erode the beaches by breaking the rocks. In coastal erosion land is permanently and completely shifted from one region to another. The intensity of erosion along a beach is influenced by how hard a wave hits it; the intensity of the wave depends on tides and the water density. Coast erosion usually affects most people that live along the coastline and also the marine organisms that have their habitats along estuaries, bays and very shallow parts of the ocean water.

Discussion

Many coastline are facing rampant coastal erosion and mostly in the Atlantic and gulf where erosion percentages are about 6% per year. Many coastlines within the United States of America have been affected by coastal erosion and in our study today we will concentrate on the coastal erosion in Louisiana specifically along the Mississippi river. Wetlands within the United States are declining at a very fast rate in the past 200 years, this because of the increase in the natural evolutionary processes and also some human activities such as dredging. The wetlands within Louisiana are vast and wide as they extend to about 130 kilometers inland and 300km onshore. Various wetlands within the U.S.A are in stable conditions but the one in Louisiana if not quickly addressed it will be completely eroded in the next two hundred years (Dunne and Knapp 123).

The delta plains within the Mississippi river together with its shorelines have been the recipient of sediment deposition by the river dating back to seven thousand years back. There have been shifts in the course of the Mississippi river which has resulted in the staking of sand and mud which later formed deltas which were abandoned by the changing of the river course. These delta began eroding and degrading reason being the following factors; the subsequent increase in the water level which may have been caused by global warming, bombardment by the loose sediment which may have been deposited and also the reason may have been the sudden occurrence of storms which could have washed away the sand particles which were deposited on the deltas. Other than the above reasons the natural marine processes did erode the margins of the deltas which were seaward leading to the formation of barrier beaches and also sandy headlands. Erosion subsequently continued resulting to the barrier islands which were of low relief and eventually causing separation with the main land by lagoons and shallow bays

The erosion of the coastal shorelines in Louisiana has really led to the environmental and economic decline of the region as compared to the past. If urgent measures are not addressed the wetland in Louisiana will be no more. Due to the erosion of the deltas there was formation of barrier islands which acted as buffer zones hence leading to the decline of the ocean wave effects to the surrounding wetland and estuaries. Researchers have come up with findings that tend to explain that if the eroding of the barrier islands continue they will be no more by the climax of this century hence exposing the wetlands to the mighty force of marine processes which include; tidal power, transportation of sediments, wave action and the intrusion of salinity. These marine processes will therefore lead to the degrading of the wetlands. Coastal erosion which is also known as shoreline retreat can cause a lot of economic losses since the following sectors are adversely affected and they include ; agriculture, tourism which to some countries is the main source of income, fishing and shipping as harbors are also affected (Finkl and Khalil 206).

In Louisiana there are oil refineries and energy production sites and therefore through coastal erosion such activities are hampered and disrupted. In certain estimation by economists it was noted that if oil refineries in Louisiana were to be hampered for three continuous weeks then the country’s economy could suffer a setback of three hundred thousand jobs and also the loss of over one billion dollars. In a study conducted by waldemar nelson he states that if the coastal erosion is not corrected then the following economic conditions are likely to be affected: the transportation of oil and gas may be disrupted, navigation will also be hampered as erosion will make it difficult to navigate through the Mississippi river, commercial fishing may be hampered and some recreational activities like surfing may be affected. These are the direct impacts that may accrue as a result of coastal erosion. In a study conducted by Richardson and Scott they stated that coast erosion will impact a lot in the general economy of the United States of America. They further stated that there will be loss of jobs, decline in the household earnings and some of the business transitions of economy may be affected if the coastal erosion continues to disrupt industries in Louisiana. These are the indirect challenges that Louisiana may face as a result of the coastal erosion.

Louisiana has had a decline in its wetlands for the past thirty years or so due to this a body of experts was formed to address this problem. This body was known as coastal wetlands planning, protection and restoration act which was made up of a task force whose responsibility was to keenly monitor, implement and design the conservation of the coast and also they were to make a follow up of the restoration projects that were being undertaken (Limnological Society of Southern Africa 81). For the purpose of their duties these task force were u fed with the high resolution and colored photographs of the region which were usually taken through aerial photography. These photographs enabled them to monitor the restoration progress and this was to continue for a period of twenty years. This taskforce always submitted a report of its findings and restoration projects to the congress. The projects to be undertaken were usually ranked regarding their costs and the benefits that were to be acquired from it.

There is a formula which was used in accessing the benefits and it’s calculated through a methodology which is usually known as the wetland value assessment. Every year restoration projects were to be done and they include; restoration of the hydrology, protection of the shoreline, restoration of the barrier island, diversions of sediments, marsh management, proper use the material which is dredged, introduction of fresh water, planting vegetation and trapping of nutrients and sediments. A special body was established to monitor the progress and effectiveness of the projects. In the restoration of the coastal erosion in Louisiana the project needed an approximate of five hundred billion dollars to one billion dollar. These amounts were to assist in the protection of Louisiana against hurricane attacks (Morton 08).

It is noted that it is not nature alone that is to be blamed on the degradation and destruction of wetlands in Louisiana but also the human activities which have been taking place in the Mississippi river delta. The following are some of the activities; there has been construction of levees which were designed to channel the rivers’ waters two thousand kilometers inland hence leading to the transportation of sediments which were deposited far from the coast. This sediment was of importance as they usually nourished the wetlands. Another human activity that has degraded the coast was the dredging of canals which were to be used in the facilitating of hydrocarbon exploration and its production, these led to the intrusion of salty water to the wetland from the Gulf of Mexico. Finally the drainage of water into the wetland so as to give room for development and agriculture has led to the loss and subsequent deterioration of the wetland (Finkl and Khalil 187).

There are various ideas which have been put forward to address the problem of erosion of the Barrier Island and wetlands. Some of the ideas include; the restoration of the coast through the nourishment of the barrier island, sand and other materials that were dredged to be distributed to the wetlands, some other people state that a new navigation channel to be created so as to allow the delta plains to proceed normally with their erosion. These ideas still have their pros and cons as they still affect some communities, some interests in agriculture and also the petroleum and oil industry. There are various engineering solutions which are very expensive to implement for instance building of breakwaters so as to prevent the full force of the waves from hitting the wetland and also building of breakwaters.

This idea is viable but it is very costly. The only way curb this problem is by understanding how wetlands and barrier islands change or evolve. Various coordinated studies are showing how the nature intended both the wetland and barrier island to work. Therefore in the planning process the researchers should take into consideration how they evolve rather than going contrary to Mother Nature. Some studies are also trying to examine the possibilities of replacing sediments with very fine grained sediments. All this are very good and attainable ideas but up to date all the engineering actions performed are still fruitless (Dunne and Knapp 128).

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