Tropical forest: characteristics and climate

The tropical forest It is one of the most interesting and complex biomes on our planet, a universe of biodiversity to love and respect. It is defined as tropical because it is located along the equatorial belt, between the Tropic of Cancer to the south and the Tropic of Capricorn to the north. And it is considered the true green lung of the Earth.

If we are wondering what is meant by tropical forest, the first step to consider is in fact its geographical location. But among the characteristics of this ecosystem there is not only the vast area capable of connecting Malaysia to Latin America, up to the south-eastern African areas, and ending in northern Australia.

Tropical rainforests are also the kingdom of biodiversity, as mentioned, a cradle of varieties of flora and fauna not fully documented. In fact, science today considers 15 thousand living species that find space in these areas of the world. But studies are still underway to detect the presence of plants and animals not yet known.

Another important fact is the climate of this area straddling the Equator, which is affected by widespread precipitation and temperatures that generally never fall below 20° C, with a few exceptions at higher altitudes. But in general, the fluctuations during the course of the year are minimal.

What are the characteristics of tropical forests?

We saw it briefly in the beginning of the article, but one of the characteristics of tropical rainforests is the hot and humid climate typical of the equatorial belt. Due to the abundant solar radiation, tropical rainforests are warm all year round, with temperatures ranging from about 22° to 34° C, moderated by high humidity.

In fact, rainforests are subject to heavy rainsat least 2,000 mm, but in some areas it exceeds 10,920 mm every year. The equatorial regions boast rainfall that can last from January to December with no apparent wet or dry season, although many forests have seasonal rains.

But even then, during the times of year when there is less rain, the constant cloud cover is enough to keep the air moist and prevent the plants from drying out. The stable climate, with evenly distributed precipitation and heat, allows most trees to never lose their foliage.

The terrain

Another characteristic of tropical rainforests is the soil, which, despite what one might imagine, is not very fertile. The climatic conditions lead to a deep disintegration of the rocks and the development of soils rich in insoluble iron and aluminum oxides, called tropical red earths.

And because precipitation almost always exceeds evapotranspiration, we have an almost permanent surplus of water in the land that moves downward, arriving in the streams and rivers at the bottom of the valley. This is a natural process that tends to deplete the soil of its nutrients.

In fact, dense vegetation does not draw on the lower layers of the soil to obtain nutrients, but the roots of plants, including those of trees, are concentrated in the most superficial layers of the soil. This is where the nutrients that derive from organic waste, such as the decomposition of leaves, are found.

Tropical Rainforest Plants

Tropical rainforests are our green lungs: they occupy only 6% of the planet’s surface, but they are able to provide oxygen and retain environmental CO2. But how many plants are found in these diverse areas of the world? There are no precise numbers in this case, because new plant species are discovered every year.

Certainly some tree families are more present, such as palms, although they vary from region to region, but lianas are also not lacking. However, it should be remembered that tropical rainforests are also known for epiphytic plants, which rely on tree canopies to access sunlight.

An interesting fact: scientists have documented more than 15,000 species of plants in the current rainforests of Borneo, including 2,500 species of orchids, which are epiphytes. If we think that plant species are all the same, in every tropical area, we risk being wrong. And we will see this in detail below.

The climatic characteristics of tropical forests are roughly the same along the entire equatorial belt, but the vegetation varies in different areas. This means that you cannot expect to see the same species in the African or Brazilian areas, even though the soil and rainfall are similar.

Rainforest: fauna and flora live in symbiosis

The same argument made for plants is also valid for the fauna present in the tropical forest: from insects to mammals, each area has its own species. In reality, the variety of flora that we find often depends on the animals. And on this, on the other hand, depends the subsistence of animals, be they birds or mammals.

From insects to primates to kangaroos

An example? Costa Rica, where the kapok tree is pollinated by batsbut let’s not forget the Amazon basin, where the Brazil nut is pollinated by bees and the seeds are dispersed by the agoutis, a type of large rodent native to Central and South America.

In Madagascar, the traveler’s palm is pollinated by lemurs, small primates endemic to the island, while the seeds are dispersed by parrots. In Borneo, fig trees are pollinated by fig wasps, while the seeds are dispersed by orangutans, one of the great apes.

When it comes to insects, tropical forests are a habitat that hosts countless varieties of specimens and the data does not lie about this. For example, a study of four different types of tropical rainforest in Brazil revealed 1,080 species of beetles, not counting the various species of spiders in the Amazon rainforest.

And speaking of monkeys, while they are typical of tropical rainforests in both the New and Old World, they are absent from New Guinea. Tree kangaroos inhabit tropical rainforest areas only in Australia and New Guinea, as are birds of paradise, which are limited to the same geographic areas.

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