Geography

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Reasons for Desertification

“Desertification is a type of land degradation in which a relatively dry land region becomes increasingly arid, typically losing its bodies of water as well as vegetation and wildlife. It is caused by a variety of factors. The Factors are :

Climate change

Human activities.​​​​​

Drought

Forest Fire

Poor Irrigation Techniques

Overgrazing

Diverting Rivers

Reasons for Deforestation

Deforestation is the process of removing trees in order to clear land. Factor or cause of deforestation are :

Clearing For livestock

Logging

Agriculture Expansion

Infrastructure Expansion

Overpopulation

Rainforest

Where is it?

Tropical Rainforests are located near the equator. Fifty-seven percent of all tropical rainforests are found in Latin America. One-third of the world's tropical rainforests are in Brazil. Other tropical rainforests are located in Southeast Asia and the Pacific Islands (25% of the world's tropical rainforests) and West Africa (18%).

Climate , Temperature & Rainfall

The temperature in the rainforests rarely gets higher than 93 °F (34 °C) or drops below 68 °F (20 °C)

An average of 50 to 260 inches (125 to 660 cm.) of rain falls yearly rainfall is often more than 100 inches a year.

The Rainforest Climate In an average year the tropical rainforest, the climate is very humid and the average humidity is between 77 and 88%.

Deresrts

A desert is a barren area of a landscape where little precipitation occurs and consequently, living conditions are hostile to plant and animal life. The lack of vegetation exposes the unprotected surface of the ground to the processes of denudation. About one-third of the land surface of the world is arid or semi-arid. The desert biome is an ecosystem that forms due to the low level of rainfall it receives each year. Deserts cover about 20% of the Earth. There are four major types of a desert in this biome - hot and dry, semiarid, coastal, and cold. They are all able to inhibit plant and animal life that are able to survive there.

Facts

The vegetation does not grow very tall so the desert biome can only accommodate small animals, rodents, and reptiles. These animals can escape the harsh Sun by hiding under small scrubs or hiding in burrows.

Many desert animals tend to be nocturnal, sleeping during the day and coming out at night when the temperatures are more tolerable.

Because there is hardly any standing water in the desert biome, animals either store water in their bodies or get their water needs met by the foods they eat.

Dust storms occur when the wind picks up dust from the surface. These storms can be up to 1 mile high and travel over a hundred miles.

The plants that are able to grow in the desert biome store water in their stem. They normally grow spaced out so that their roots can extend and find water.

Some deserts are so hot that when it rains, the water evaporates into the air before ever hitting the ground.

The driest desert on Earth receives on average 1 centimeter of rainfall every 5 to 20 years.

Savanna

the savanna biome is an area that has a very dry season and then a very wet season. They are situated between a grassland and a forest. They can also overlap with other biomes. There are savanna's located in Africa, South America, India, and Australia. The savanna is a mixed woodland grassland ecosystem characterized by the trees being sufficiently widely spaced so that the canopy does not close

Great Green Wall

The Great Green Wall, or Great Green Wall of the Sahara and the Sahel Initiative, is Africa's flagship initiative to combat the effects of climate change and desertification. The Great Green Wall is a project which is meant to help stop and reverse effect of desertification. The project is meant to cover a Segal to Djibouti in green and it is 8000km long and 15000km wide. It includes 11 countries which are Burkina Faso Chad Djibouti Eritrea Ethiopia Mali Mauritania Niger Nigeria Senegal Sudan and has been around for 10 years starting in 2007. This project has multiple advantages besides just stopping desertification. The advantages of the Great Green Wall are First, the wall will protect vital water sources in the area and even help create new ones. It is hoped that the water table will become rejuvenated via surplus rainfall and this will lead to the regrowth of large bodies of water such as Lake Chad, which has been reduced by 95% since the 1960’s.

The wall will also provide food in the form of fruit and vegetables, as well as environmentally friendly fuel. For example in Senegal, Acacia Nilotic are being planted in vast numbers, which produce fruit for animal feed and components of certain medicines.

Lastly, it is hoped that the great green wall can become a symbol of unity across a continent which has too often been ravaged by war. Perhaps the cohesion required to undertake such a project will provide political stability in a region which so desperately needs to join forces to tackle the larger issues of our time.

Just like all projects the Great Green Wall has it issues critics say that it is simply too big to work as it stretches across such vast economical. An alternative suggestion that has been proposed is to simply let nature take its course. This has been successful in Niger, where farmers have taken to planting crops around naturally occurring flora. The results have been incredible, with 12 million acres of trees growing in the area since the 1980’s.

The UN and other company have offered to sponsors this project which is meant to cost around $8 Million

Prevailing Winds

Plant and Animals Adaptations

Adaptations help organisms survive in their ecological niche or habitat; adaptations can be anatomical, behavioral or physiological.

Anatomical adaptations are physical features such as the shape of an animal. Behavioural adaptations can be inherited or learned and include tool use, language, and swarming behavior. Physiological adaptations include the ability to make venom; but also more general functions such as temperature regulation.

Flight

Camouflage

Bright color and spots( tell us that that animal is poisonous )

Resource Conservation

Hair

Epiphytes (are plants that live on the surface of other plants. they do that to take advantage of the sunlight on the canopy)

Pitcher Plants