Peter,+Michelle,+Tim's+Group

= Desertification of the Sahel =

Desertification


Desertification is the process by which dryland ecosystems is degraded and turned into desert. Desertification is caused by both anthropogenic and climatic factors. The most immediate cause of desertification is the removal of vegetation brought about by the unsustainable use of natural resources. Overgrazing is the major cause of desertification worldwide; vegetation is instrumental in soil conservation and in the regulation of surface water and climate, and destruction of vegetation leads to soil erosion that furthers the cycle of reduced soil conservation and desertification. Other human causes of desertification include destruction of vegetation for firewood, incorrect irrigation practices that cause salinization and inhibit plant growth, and farming land without allowing it to replenish itself. Increasing population and poverty also contribute to desertification, as those living in poverty are more likely to overuse the environment without thought for sustainability.

Climate change also contributes to desertification. Climate change has been linked to increased occurrences of extreme events, such as droughts, floods, and fires - all of which contribute to the reduction of vegetation. Droughts in particular have been shown to dramatically increase rate of desertification when coinciding with the anthropogenic factors listed above. Furthermore, as climate change is linked to increasing atmospheric levels of CO2, desertification - which cyclically causes reduction of vegetation - causes less CO2 to be absorbed by vegetation, thus exacerbating the problem into a vicious cycle.

Desertification reduces the ability of the region to support life, affecting the biodiversity, agricultural crops, and people. The reduction of vegetation that accompanies desertification causes hastened soil erosion - topsoil is lost, rain drop impact is increased, and surface runoff is increased. The decrease in vegetation leads to a lower water retention by the soil, and also contributes to a decline of nutrients within the soil, all of which contribute to a further inability to support plant life. Worst of all, desertification is self-compounding: once the process begins, it continues in a vicious cycle and affects adjacent land, as well.

Sahel
 The Sahel is a long, thin region of scrubland and desert spanning across Ethiopia, Eritrea, Djibouti, and Somalia. It is defined by its climate, and is the transition zone between the Sahara desert to the north and the tropical, equatorial continental interior to the south.



 Desertification in the Sahel is progressing at a quick rate, with 2,500 hectares being subject to desertification each year. Desertification is a widespread problem in the region; to illustrate, the continued dry period for the 1970s and early 1980s devastated much of the Sahel and was estimated as responsible for 100,000 to 250,000 deaths, destitution of many millions, and long-term agricultural consequences in five nations.

 The primary cause of desertification in the Sahel is slash-and-burn farming, in which forests are cut and burn to provide land for annual agriculture. As forests are destroyed, soil retention is lowered, and levels of topsoil are removed by wind, transforming the area into an arid, sandy devastation not able to support life. Despite this, farmers continue to degrade their environment through unsustainable agricultural practices, such as cutting down the millet stalks after harvest and exposing the farmland to wind until the next sowing seasons. The slash-and-burn farming can be attributed to a number of human factors, such as population increase, extreme poverty, bad irrigation techniques, lack of education on sustainable agricultural methods, and lack of access to technology.



 In transition zones like the Sahel, drought is a common occurrence, but wet and dry periods tend to last for many years. The Sahel suffers from long periods of drought mixed with periods of torrential rainfall in August and September. The torrential rains often cause harm to crops and sometimes act as a factor of desertification.

 Due to prevailing desertification, the soil of the Sahel is mostly dry and sand-like: easily blown by the wind, lacking humus, and nearly infertile. The soil is also prone to being washed away during the torrential rains that the Sahel occasionally experiences, eliminating the valuable topsoil that is essential for support of vegetation. Continued desertification in the Sahel has dramatically decreased the agricultural fertility, infrastructure, and output of the land.



Possible Solution
 A recent trend of greening in the Sahel accompanied increases in rainfall and slowing down of desertification. In fact, this trend may be even more significant than climate variability alone, and may be the result of social, ecological, climate, and land management factors.

The creation of a 'green wall' - a region of vegetation between the Sahel and the Sahara aimed at limiting desertification - is currently envisioned by African countries on the southern border of the Sahara. The green wall would theoretically be resistant to desertification and thus prevent it from further impacting the Sahel.

 Given the vast area of the Sahel and the imperfect communication and transportation in this area, perhaps the most appropriate solution would be the promotion of sustainable environmental practices and the encouragement of farmers to revegetate their own land as they are cultivating throughout the Sahel. For instance, some villages in the Sahel have set up Naam groups, which have implemented environmentally responsible measures such as stone stoves, wells, cereal banks, and various village projects.

**Oil pollution**


The oceans are polluted from dumping oil, spilling, and shipping through a daily basis. These oil pollution mainly happen when people make careless mistakes and leak the oil tanker into the water. Oil spills from tankers cause a severe problem because massive amounts of oil will spread. Oil could also leak when equipment breaks down as the tanker drowns and gets stuck on land under water. Oil spills make up to about 12% of the oil that enter the ocean. The rest comes from shipping, draining, and dumping. Oil spill may also occur often when countries are at war. A rival country may decide to dump oil into the other country’s ocean.

 Furthermore, terrorists may cause oil spill to receive attention or to notify their targeted country. People also dump oil into the ocean illegally due to their self-centeredness and laziness. They do not want to spend their own money and do the work of decomposing the waste oil. Oil spill may happen out of people’s control. Natural disasters like hurricanes may let the oil pour out by flipping the oil tanker over.

The number one victim for oil pollutions are the animals. Oil forms a thick sludge in the water because it does not dissolve in water. The sludge will suffocate most of the local marine animals. Birds, for example, die when their feathers get covered in oil. The oil is too heavy for the birds to fly. Its effort to clean itself will poison the bird even more. The oils may get into the animal’s lungs or liver, blind them, and cause hypothermia, in which the animal’s body temperature will lower.

Oil spills may even have a huge effect in endangering a species. An example is the killer whales. Oil spills have led these kill whales to be endangered. The oil kills the killer whales by being eaten or entering the whale’s blowhole. The blowhole is the hole that allows them to breathe. However, if this blowhole is blocked with oil, the killer whale will no longer be able to breathe. The oil could also kill the killer whales when these whales eat fish that swam through the oil. Eating these fish means eating oil, which will poison and kill the killer whale.

**Nigerian Delta**


The Niger Delta is formed primarily by sediment deposition, which covers about 20,000 km squared. It is the third-largest basin in Africa and the largest wetland. It is well-known for having one of the highest concentrations of biodiversity.

People are witnessing a gradual poisoning and destruction of vegetation and land due to oil spills. Although this is an on-going and severe problem, no effective efforts has been made to prevent or even slow down these environmental problems.

Likewise, oil spills are a common occurrence in Nigeria. Campaigners say that there are about 300 oil spills every year in the Nigerian Delta. Some of the causes include spills due to inadequate equipments, sabotage, damage of tankers, and during oil production operations.Oil spills due to the corrosions of the pipes and tankers are one of the main causes for the pollution. The numerous connections of the narrow pipes increase the possibility of oil leaks.

Oil spill has led to vast consequences. Many forests has been destroyed as it wiped out by settlement or oil. The rainforest which covered up to 7,400 km squared all disappeared. These spills destroyed all the crops and contaminated the soils and groundwater as well. Because of this, the region's supply of food were often inadequate.

It had a direct influence on humans as well. People had to deal with health issues including breathing problems and skin lesions. Many experienced a huge loss of both their property and rights. They suffered from the lack of supply of food, health issues, contaminated water and food, and the condition and ability to work.



<span style="font-size: 1.1em; margin: 0px; padding-bottom: 0px; padding-left: 0px; padding-right: 0px; padding-top: 5px;">**Possible Solution**


<span style="font-size: 110%; font: normal normal normal 13px/normal Arial; letter-spacing: 0px; margin: 0px;">One of the best ways to deal with oil spills to let it naturally break down. However, when dealing with excessive amounts of oil spill, dispersants may help. Dispersants are chemicals that break down the tension that keeps the oil and the water separated from each other. Then oil can be collected in smaller droplets and can sink. These chemicals also allows for easier and greater natural breakdown.

<span style="font-size: 110%; font: normal normal normal 13px/normal Arial; letter-spacing: 0px; margin: 0px;">Another way that helps its breakdown are the biological agents. They help oil spread apart and break down naturally. Some of these fertilizing agents include nitrogen and phosphorous.

<span style="font-size: 110%; font: normal normal normal 13px/normal Arial; letter-spacing: 0px; margin: 0px;">In order for solve this problem to resolve as soon as possible, people should be notified with the problem's severity and should show interest and care. People should use less products that use oil by using environmentally household products. Some of them include washing powder and household cleaning agents. Conserving water by using the water when it is necessary can also be a great help. This will reduce the amount of water needed to be cleaned and will also prevent water shortages. To prevent the overall water pollution, people should stop littering into the lakes and oceans.

<span style="font-size: 110%; font: normal normal normal 13px/normal Arial; letter-spacing: 0px; margin: 0px;">A big difference will be made if each and every one of us care for what is happening around us and not lay the responsibility on others.

<span style="font-size: 1.1em; margin: 0px; padding-bottom: 0px; padding-left: 0px; padding-right: 0px; padding-top: 5px;">**Works Cited**
<span style="color: #333333; font-family: 'times new roman',times,serif; font-size: 12px; letter-spacing: 2px; line-height: normal;">"Disaster Prevention and Management." Emerald. Emerald Group Publishing Limited, 1992. Web. 2 May 2011. <http://www.emeraldinsight.com/journals.htm?articleid=1839408&show=html>.

<span style="color: #333333; font-family: 'times new roman',times,serif; font-size: 12px; letter-spacing: 2px; line-height: normal;">"Nigerian Delta." N.p., n.d. Web. 1 May 2011. <http://en.wikipedia.org/wiki/Environmental_issues_in_the_Niger_Delta>.

<span style="color: #333333; font-family: 'times new roman',times,serif; font-size: 12px; letter-spacing: 2px; line-height: normal;">"Oil pollution." N.p., n.d. Web. 1 May 2011. <http://library.thinkquest.org/CR0215471/oil_spills.htm >.

<span style="color: #333333; font-family: 'times new roman',times,serif; font-size: 12px; letter-spacing: 2px; line-height: normal;">"Oil Spill." N.p., n.d. Web. 1 May 2011. <http://water-pollution.wp.fubra.vc.catn.com/oilpollution.html >.

<span style="color: #333333; font-family: 'times new roman',times,serif; font-size: 12px; letter-spacing: 2px; line-height: normal;">"Solutions for oil spills." N.p., n.d. Web. 1 May 2011. <http://www.ehow.com/way_5201147_solutions-oil-spills.html >.

= The Aswan Dam =

Environmental Impact of Dams


Currently, there are around 40,000 large dams that obstruct the world’s rivers. The construction of dams cause an upheaval in the environment of the water and land, thus contributing to the ecosystem’s destruction. The dams completely stop the circulation systems of the ecosystem and contribute to a myriad of problems.

First, dams contribute to the erosion of soil. Dams hold back the sediment normally found in river flow, thus preventing it from reaching the downstream. The downstream water erodes the adjacent channels and banks to make up for the lack of sediment. This destruction of riverbed contributes to a destruction of vegetation and river life. Dams, by preventing floods from occurring, interfere with the ecosystem that is naturally adapted to the periodic flooding.

Second, dams lacking bypass systems interfere with the life cycles of fish and other marine animals, and can causes species extinction and loss of biodiversity.

Third, dam reservoirs, due to the slow water movement, serve as breeding grounds for mosquitoes, snails, and flies - vectors of diseases such as malaria, schistomiasis, and river blindness.

Last, the construction of dam often displaces native people and interferes with their way of life. A large number of fisher communities depend on fishing for livelihood, but the construction of dams cause the number of fisheries to decline.

<span style="font-size: 1.1em; margin: 0px; padding-bottom: 0px; padding-left: 0px; padding-right: 0px; padding-top: 5px;">** Aswan Dam **


The Aswan Dam is located across the Nile River in Aswan, Egypt. It was constructed between the years 1960 and 1970. Its purpose for its construction was economic development through regulation of annual river flooding and causing of hydroelectricity. The dam overall greatly influenced Egypt economically and culturally.

The Nile River's annual flooding enriched the soil by bringing nutrients and minerals into the delta. The dam made the area an ideal place for farming. However, because the amount of flooding varies, droughts and floods were a problem near the Nile River.

<span style="font-size: 110%; font: normal normal normal 12px/normal Verdana; letter-spacing: 0px; margin: 0px;">However, the Aswan High Dam caused several environmental and economic issues. One of the main issues deal with the huge deposits of silt that are held behind the dam. For the past years, this had made the Nile floodplains extremely fertile. However, coastal erosions occurred and there was a lack of nutrients for those farming the land. Thus, the farmers are forced to use fertilizers to due the infertile land. Their excessive use have been causing serious chemical pollution. Many also blame the Aswan High Dam for the reduction in fish catches in the Mediterranean.

<span style="font-size: 110%; font: normal normal normal 12px/normal Verdana; letter-spacing: 0px; margin: 0px;">The overall reduction of health education, rural clinics, sanitation, and the supply of clean water has been caused during the pre-dam period.



Possible Solutions
The primary possible solution to the negative impacts of the Aswan dam is to lessen Egypt’s dependency on hydroelectric power, and the only sustainable method to do so is the development of alternative sources of energy. The development of energy sources such as solar, wind, biofuels, and geothermal will allow Egypt and the rest of the world to move away from the energy sources prevalent today, which mostly come with significant environmental challenges.