The Negative Human Effects On Marine Resources Environmental Sciences Essay

What negative effects do human activities have on Marine and Coastal resources from Addington Beach to Aliwal Shoal?

The coastline of South Africa stretches for 3000km of which 80% consists of sandy beaches backed by low sand dunes. The focused areas of Addington Beach through to Aliwal Shoal, which contain diversity of fish and other species (including whales, seabirds and tunas), provide opportunities for economic and social activities including development opportunities, fishing, agriculture and recreation. These resources are important as they make up a rich asset to the Southern Coastal areas of South Africa. However, Marine and Coastal resources such as these areas all along the South African coast are being affected negatively due to driving forces mostly caused by various human activities. Pressures affecting these resources include population growth and coastal human settlements, emissions to sea by shipping and sewage and the extracting of natural resources such as fishing or sea bed mining.

General pressures and effects of human influences:

Population growth is the biggest driving force for environmental changes of marine and coastal resources in South Africa. The increasing population is strongly dependant on production activities to increase service and manufacturing industries and therefore is increasingly dependant on ports such as Durban Harbour for the import and export of products. Demands for food, recreation and land for housing all increase the pressures on the coastal resources. Statistics state that 30% of the South African population lives along the coastline due to in-migration of those seeking jobs, people retiring and those seeking a life of better quality. Because of this increase of dependency the coastal cities have developed rapidly and are as a result having negative influences on the marine and coastal resources. Irreversible changes are occurring due to these influences such as overexploitation of resources, destruction of natural habitats and an increase of wastes and pollution which smother and kill organisms and lead to water quality deterioration.

POPULATION GROWTH GRAPH/TABLE.

Emissions to sea by sewage and shipping are also a huge cause of the negative effects of marine and coastal resources. Daily industrial effluents and sewage are released into the sea via discharge pipelines near Durban Harbour and by sewage pipes all alone the south coast. These emissions are not only harmful to human health but also have a devastating effect on water quality and may contaminate many organisms.

FIGURE 4.8 (effluent pipelines off the South African coast after Cloete 1979)

Shipping is also a serious contributor to the degrading of marine and coastal resources. South Africa is situated on one of the biggest ship transport routes of the world and Durban Harbour is one of the few ports often stopped at. Due to weather and sea conditions and the wait to be docked in the port, major marine pollution incidents take place as oil spills and waste dumping takes place. Waters are thus polluted and these wastes and pollutions are transported along the south coast, by the Aguhlus current, and infect and destroy resources along the coastlines of South Africa.

The extracting of natural resources such as fishing too affects the marine and coastal resources. Both commercial and recreational fishing are primary economic activities which together can generate more than 158 000 people and R3 billion annually (CMPP, 2005). The improvement of fishing methods results in a greater number and variety of fish being caught and as a consequence of this, fish stocks are decreasing in size and several species are facing possible extinction. Other human recreational activities, besides fishing, that may negatively affect marine and coastal resources include scuba diving or yachting.

TABLE OF DATA FOR FISH NUMBERS:

Durban Harbour and Addington Beach:

IMAGE OF POLLUTION IN DURBAN HARBOUR:

Both the Durban Harbour and Addington Beach are sound examples of coastal areas that have been urbanized and as a result are polluted and negatively effected by human activity. Shipping and the wastes excreted by the industrial companies in the Durban harbour area are a huge cost to the marine and coastal resources in the area. Fish and other animals are being killed or having their habitats affected or destroyed and the general water pollution in the area has increased drastically over the past few years and as a result the water quality has rapidly decreased.

FIGURE 4.10 (Isogram depicting classification of the surf-zone at 28 sampling stations)

The harbour pollution caused by oil and chemical spills, organic waste dumping and general excretions by the ships docking at the harbour or waiting out at sea to be docked in port. This pollution be the harbour is affecting the resources of surrounding beaches as well, such as North Beach, South Beach, Bay of Plenty and Addington Beach who as a result of the pollution have each lost their Blue Flag status after failing water quality tests. These losses of our Blue Flag status has also had negative effects on the tourism industry but most importantly reinforces the fact that the water quality and pollution is at an unacceptable level and the surrounding litter and destruction of the coasts have too become a state of disaster.

Reports about heavily polluted water flowing into the Durban Harbour via the Umhlatuzana River for periods of nine months have also surfaced in recent years. Illegal discharges of wastes and sewage are being flooded into the Durban areas and are too polluting the water badly and destroying species and habitats and are decreasing fish stocks. (Raven, 2008). A great concern about these pollutions and wastes entering the sea near the Durban harbour and other areas is that these wastes are being transported all along the coast of South Africa via the Aguhlus current right down to areas such as Aliwal Shoal. Aliwal Shoal is not only an area being affected by wastes from human urbanization but also by recreational activities and tourism sites.

IMAGE OF ALGUHLAS CURRENT

Aliwal Shoal:

DIAGRAM OF ALIWAL SHOAL:

Aliwal Shoal is 50km south of Durban, was formed by a sand dune almost 80 000 years ago and is the home of many different species of fish and other marine organisms such as sea turtles, humpback whales, dolphins and the tiger shark. Recently there has been a hard battle to preserve Aliwal Shoal and many have taken a stand to fight for the protection of the area and marine life from pollution and tourists. Due to the research that was started over 10 years ago by the Natal Sharks Board, the region of Aliwal Shoal has been threatened by environmental pollution. Divers would report on the behaviour of sand tiger sharks at monthly meetings after observing them during dives and collecting data. During the early years of research destruction of Aliwal Shoal became a large concern as the Saiccor cellulose plant, being dumped into the ocean at Umkomaas, was untreated and was polluting the waters. The matter reduced visibility and formed foam that made beaches unusable. However, a solution to this was found by the “South Coast Marine Pipeline Forum (SCMPLF)”. The Saiccor pipelines were extended to a water treatment plant and the water quality in Aliwal started to improve.

The next problem is rooted in this sudden improvement to clear water as diving tourism became very appealing to many. At certain times 20 boats can be seen on the Aliwal Shoal and some even equipped with spears for the sharks and other marine life. In 2009, a huge movement to receive the necessary protection of Aliwal Shoal from pollution and excessive diving is being driven. This unique marine region is in need of laws and regulations that protect it from any more damages to the environment that may be caused by detrimental human activities such as dumping, shipping, pollution transported from Durban Harbour and diving. (Andrew C.R, 2009).