Map of Madagascar

Tropical rainforest ecosystems are located between the tropic of cancer and the tropic of capricorn, usually placed around the equator, as seen above. The reason for the warm and wet climate is due to the ITCZ, Intertropcial Convergent Zone; is a rainmaking machine that travels along a path of trade winds created by the northern and southern hemisphere. The ITCZ is unstable and it moves according to the tilt of the Earth.

This map also depicts the island of Madagascar and its relationship with the world. Madagascar is a small island located in the Indian ocean, off the coast of Africa. It is located approximately between latitude 12°S and 26°S, and longitudes 43°E and 51°E. It is the fourth largest island in the world and it is a biodiversity hotspot because it has high diversity, high endemism, and an exceptional degree of threat.

This is a satellite view of Madagascar. As you can see the island is mostly covered in tropical dry forest, except a thin line of vegetation located on the east coast. This is where Madagascar's tropical lowland forest is located. It covers about 112,600 km of land though it is only a third of its original size. 

Madagascar's Tropical Rainforest

Coquerel's Sifaka

Ring-tailed Lemur

 Pitcher plant

What did the ecosystem historically look like?

Madagascar was originally connected to the continent of Africa, however because of the continental drift; Madagascar became an island about 165 million years ago. The few animals on board the new island were then forced to adapt to the new environmental conditions. Several animals migrated to the island on drifting pieces of wood or vegetation.

Over the past decade, the forest has lost a lot of is tree coverage, as seen in the figure on the left. Originally Madagascar's tropical rainforest covered 11.2 million hectares, today, only about 2.5 to 6.9 million hectares remain. Today, less than 10% of the original forest remains. Rain forests are disappearing primarily because of agriculture, forest fires, and logging.

There are two types of agriculture that take place on the island: subsistence and commerce agriculture. Both use the method of slash-and-burn agriculture, in which the plants are cut, burned, and the planted with crops. This type of agriculture is unsustainable.

Forest fires are unpredictable and burn through as much as one third of the island each year. This is often due to slash-and-burn agriculture. When they burn the land, the fire is often uncontrollable causing the fire to spread into a wildfire. This causes the island to lose much of its unique diversity.

Like almost all tropical rainforest ecosystems, logging provides for shifting cultivation, grazing, fuel wood gathering, economic development, cattle ranching and mining. In addition, the tropical rain forests of Madagascar contain many precious woods that can be used for timber, such as ebony and rosewood.

Despite these environmental hazards, some plants that were present historically have survived. Several native plants located in the tropical rainforest include rosy periwinkle, orchids, and palms. Other native plants located on the island are baobab trees and alluaudia.

Catharathus Roseus (Rosy Periwinkle)

The Catharathus Roseus is both native and endemic to the island of Madagascar. It provides humans with important drugs that can be used to treat Hodgkin's disease and leukemia.

Cynorkis calanthoides (Cynorkis uncinata)

Orchids make up the largest group of plants in Madagascar. Many which are endangered and under threat of human activity. There are over a thousand species of orchids found in Madagascar and almost 90% of these species are endemic to the island.

Dypsis Ambositrae

Palm trees are native to the island of Madagascar and of the 170 species found, 97% of the tress are endemic. One of the most endangered palms is dypsis ambositrae, as seen on the left.







Since these plants were native to the ecosystem, these plants probably dominated the ecosystem during earlier times. However, due to non-native and alien plants, the native plants have been downsized and most are endangered. Thus, in order to restore the ecosystem back to its original habitat, it would be best to identify the native plants and start replanting them. In addition, try to remove non-native species from competing with the native species.

How have people impacted the ecosystem?

Humans are the leading contributors to the decline of Madagascar's tropical rainforest. Located within an island, the conservation status can be classified as "ugly" because of its isolation. Reasons for anthropogenic destruction of forests include agriculture, logging for timber, ranging, and fuel wood.

As a developing country, many of the residents rely on subsistence agriculture and commercial agriculture to survive. These farmers convert and deforest the rainforest into rice fields, coffee plantations, etc. Unfortunately, the method most Madagascan's use is slash-and-burn agriculture. This farming technique is unsustainable because it requires the land to be cut and burned before a crop can be planted. After the production of crops, the soil is so malnourished that it can't be used for almost seven years. Even if the land may be used again, the productivity of the soil is short-lived and only lasts a few cycles before the land is fruitless and barren. As a result, this contributes to a vicious cycle that requires Malagasy (Madagascan people) to continually cut down more of the forest to grow more crops.

Due to the impoverished economy and corruption, deforestation has been an ongoing problem in Madagascar. Though the government has set laws banning logging of the tropical rainforest, illegal logging still takes place. Most logging is targeted at valuable hardwoods only found in the forest such as rosewood and ebony. In fact, prices can go up to two thousand dollars per a ton. In addition to hardwoods, trees have been cut down for rangeland, charcoal, and fuelwood. The forest is decreasing at such an alarming rate that the situation has received international attention and pressures the Madagascan government to act promptly. According to studies, the deforestation rate in Madagascar is 2000 kilometers squared per a year, which if continued means the rainforest will be non existent in about five years.

What benefits do people get from the ecosystem?

People benefit greatly from tropical rain forests because they provide:

• Oxygen
• Rain forests are major producers of oxygen because of its large range of vegetation. The oxygen of all rain forests combined makes up 28% of the world's oxygen. 
• Absorption of carbon dioxide
• Rain forests serve as carbon sinks. They remove carbon dioxide from the air and convert it into its solid form. This is especially useful due to environmental concerns; thus rain forests help mitigate global warming. 
• Prevention of soil erosion
• Soil erosion occurs when soils are washed away with the rain into streams and rivers. The trees provide an anchor for the soil to prevent this from happening.
• Plants used in medicines
• "Tropical rain forests are called the “world's largest pharmacy” because of the large amount of natural medicines discovered there. Many of the medicines that humans use come from the rain forests." (25)
• In addition, research shows that there are numerous plants found in the rain forests that are active agains cancer cells. 
• Prevention of natural disasters (flooding, landslides, etc.)
• Since the trees provide an anchor for the soil, it prevents landslides due to loose soil. In addition, the trees absorb much water and thus prevents flooding. 
• Recycles water
• Tropical rain forests are essential to the water cycle. It is part of the transpiration process, in which leaves release water that, then, evaporate into clouds. The water is then released back into the rainforest keeping the ecosystem moist and alive. 

Are there any protected areas for that ecosystem?

National parks and reserves are the main source of forest protection in Madagascar. National parks prohibit agriculture, logging, human habitation, and hunting. Nonetheless, national parks only account for 3% of the entire island of Madagascar.

One of the largest national parks located in the tropical rainforest is Ranomafana National Park; it is spread over 435 kilometers squared and it is located in the south east portion of Madagascar. Other diverse national parks include Marojeju, Masola, and Makira. The main goal of these parks is to promote research, whilst protecting the natural state of the rainforest. However, because the area is large and spread out, it is difficult to regulate and illegal logging and poaching still occurs.

Due to human activity, only 34% of the original forest remains. Since, the forest is declining at such a fast rate, it has been added the the UNESCO World Heritage List. This prompts "a call to action from Conservation International to the international community to take swift and effective action to prevent the loss of the world's most important biological treasures." Thus, the Madagascan government was finally pressured to pass a decree, in 2010, prohibiting "the cutting, exploitation and export of rosewood and ebony in Madagascar... All persons engaged in the cutting, exploitation and export of rosewood and ebony are liable to criminal prosecution."(14) After the decree was passed, logging has decreased drastically and the forests are better maintained.

Madagascar Decree 2010 (14)

What is likely to happen in the future to that ecosystem?

 As mentioned earlier, human impact plays a large role in the rainforest ecosystem. The two major human impacts are slash-and-burn agriculture and logging. If the decree, passed in 2010, manages to prevent all illegal logging and poaching from taking place, it will eliminate one of the major problems. Nonetheless, if slash-and-burn agriculture continues to occur, the forest will still continue shrinking in size, though at a slower rate. Even worse, if the decree is ignored, the rainforest will continue to decline and shrink in size. In this case, the rainforest will continue to thin until there is almost no vegetation left to be considered a tropical rainforest. This prospect of the future is a horrifying possibility. In order to maintain the rainforest, we must come up with ways to inhibit human destruction.

Country	Area of Country	Original Forest	Present Forest	Annual Rate of
	(sq km)	Cover (sq km)	Cover (sq km)	Deforestation (sq km)
Bolivia	1,098,581	90,000	45,000	1,500
Brazil	8,511,960	2,860,000	1,800,000	50,000
C. America	522,915	500,000	55,000	3,300
Columbia	1,138,891	700,000	180,000	6,500
Congo	342,000	100,000	80,000	700
Ecuador	270,670	132,000	44,000	3,000
Indonesia	1,919,300	1,220,000	530,000	12,000
Cote D'ivoire	322,463	160,000	4,000	2,500
Laos	236,800	110,000	25,000	1,000
Madagascar	590,992	62,000	10,000	2,000
Mexico	1,967,180	400,000	110,000	7,000
Nigeria	924,000	72,000	10,000	4,000
Philippines	299,400	250,000	8,000	2,700
Thailand	513,517	435,000	22,000	6,000

According to this graph, the tropical rainforest of Madagascar is less than a quarter of its original size and the annual deforestation rate is 2,000 square kilometers per year. If this continues and a set rate, in approximately five years the tropical rainforest will no longer exist. The evidence on this graph suggest that the future of the forest is gloomy.