What are rainforests?
Rainforests are biological hotspots that contain over half of all living plants and animal species on the planet. Rainforests are characterized by high rainfall, which often results in poor soils due to the leaching of soluble nutrients. It can rain anywhere from 1750 to 2000mm annually. They form a sparse belt along the equator in a region known as the monsoon trough. Depressions and tropical cyclones often form in the vicinity of the monsoon trough, with each capable of producing a year’s worth of rainfall in a relatively short time frame. Let’s explore some of the planet’s well known tropical rainforests and discover where our rainforests found.
Rainforests of the World
The Amazon Rainforest
The Amazon Rainforest is a moist broadleaf forest that covers most of the Amazon Basin of South America (approximately 8,235,430km2). The Amazon represents over half of the planet’s remaining rainforest and is the largest and most species rich rainforest in the world. It is home to about 2.5 million insect species, tens of thousands of plant species, and about 2000 birds and mammal species. Some of the notable species in this rainforest include the black caiman, jaguar, anaconda, electric eels, and piranha. The Amazon River is notable because it, and its many tributaries, annually floods up to a depth of 40m.
The Congo Rainforest is the second largest rainforest in the world, covering 1,800,000km2 and several African countries. However, it is one of the most threatened regions on the planet. Commercial logging, clearing for subsistence farming, and civil strife has had a devastating effect in the region. Since the 1980s, Africa has had the highest deforestation rate of any region on the planet. The Democratic Republic of Congo has the greatest tract of rainforest in all of Africa. The country has established a number of parks and reserves that protect about eight percent of the Congo. This provides refuge for a number of large mammal species driven to extinction in other African countries such as gorillas, chimps, forest elephants, buffalos, and bongos.
Madagascar Lowland Forests
The Madagascar lowland forests cover approximately 112600km2 along the eastern side of the island. These rainforests are composed of dense evergreen forests. As an island, Madagascar is home to a unique set of species found nowhere else on the planet. Hundreds of species of vertebrate animals and perhaps thousands of species of plants are strictly endemic to this ecoregion. Lemurs are found nowhere else in the world except for Madagascar; other notable species include the fossa, the comet moth, mantella frogs, and over half the world’s 150 species of chameleon.
Borneo Lowland Rainforests
Southern Asia is home to the Borneo lowland forests which cover an area of 427000km2. The rainforest includes over 2000 species of orchids and 3000 tree species. This includes the massive corpse flower, which is notable for producing one off the largest flowers on the planet, and a strong odor of decaying flesh. The fauna consists of the Asian elephant, Sumatran rhinoceros, and the iconic orangutan. This region is under threat of destruction because Indonesia lacks the law enforcement to ensure its protection. Large tracts of land are susceptible to burning every year by commercial logging agricultural projects such as oil palm, rubber, and industrial timber for pulp and plywood. Slash-and-burn tactics continue unabated throughout the region.
Queensland Tropical Rainforests
The Queensland tropical rainforests cover 32700km2 of northeastern coastal Queensland. The rainforests comprise three separate regions including Cairns, Carmila, and Normandy Range. Relative to the rest of Australia, mostly semi-arid or desert, these areas receive significantly more rainfall. The Australian rainforests are home to over 700 unique species found nowhere else. This includes marsupials that have evolved to fill the niches that placental mammals fill in other regions. Queensland tropical rainforests are unique because they have high quality soil in comparison to the other rainforests of the world.
Image Credits: Image/Wikimedia Commons/Public Domain