The tropical rainforest is a diverse and complex biome located in various regions such as South and Central America, Africa, Oceania (the islands around Australia), and Asia (15). Covering approximately 7% of the Earth’s surface area (13), these rainforests are famous for their intricate structure and wide range of species. Although they share similarities in climate, precipitation, and other aspects, each region possesses its own distinctive features.
Various species in the Tropical Rainforest have the ability to adapt to different types of forests, including mangrove forests, moist forests, mountain forests, or tropical deciduous forests. The availability of sunlight plays a crucial role in determining the growth of organisms in this ecosystem. Over time, various strategies have developed to overcome the challenge of accessing light or dealing with low light conditions under the dense canopy. The Tropical Rainforest maintains a consistent climate year-round, with temperatures averaging around 80 degrees Fahrenheit and receiving abundant precipitation ranging from 100 to 400 inches annually.
The heat and moisture of the rainforest accelerate the decomposition of deceased organisms, returning their nutrients to the soil for the nourishment of other plant roots (15). This intense bacterial decay hampers the accumulation of humus, leading to infertile, weathered, and leached soil (13). Additionally, the high levels of iron and aluminum oxides in the soil give it a red color and potential mineral deposits (15). The tropical rainforest exhibits a wide variety of vegetation and animal species.
Within the rainforest, two types of plants flourish: Lianas and Epiphytes. Lianas represent rapid-growing woody vines that ascend tree trunks (15), whereas Epiphytes denote air plants that thrive on elevated branches. These plant species rely on tree limbs for support, deriving moisture from the atmosphere and capturing leaf-fall and wind-blown dust (14).
Moreover, the rainforest sustains a diverse array of animal life encompassing mammals, birds, reptiles, and amphibians. These creatures have adapted to arboreal existence by showcasing vivid hues and distinctive patterns. Additionally, they emit loud vocalizations while primarily consuming fruits (13).
The island of Borneo originated from a single underwater volcano and experienced numerous eruptions and earthquakes, resulting in the combination of land masses and the creation of the island. Currently, Borneo is internationally acknowledged as the third largest island (18) which is divided among Malaysia, Indonesia, and Brunei. The population on this island exceeds 16 million people (16), with around half of its total area, equal to 220,000 square kilometers, covered by rainforest.
The Borneo lowland rain forests, which include the Borneo peat swamp forests, heath forests, Southwest Borneo freshwater swamp forests, and Sunda Shelf mangroves (16), cover most of the island of Borneo. The central highlands of the island have the Borneo mountain rain forests at elevations above 1,000 meters (3,300 ft). Within Mount Kinabalu’s highest parts is the Kinabalu mountain alpine meadow, famous for its diverse native species including various orchids (17).
The World Wildlife Fund states that Borneo is renowned for its rich biodiversity. It is home to around 15,000 species of flowering plants and an impressive 3,000 species of trees (16). Additionally, Borneo houses diverse wildlife with 221 species of terrestrial mammals and 420 bird species. Since 1996, researchers have made significant discoveries on the island, identifying 361 new animal and plant species that showcase its unparalleled biodiversity. Moreover, Borneo plays a vital role as the central hub for the evolution and proliferation of numerous endemic plant and animal species (18). Notably, Rhinoceros Hornbills—a well-known bird species—can be found throughout Borneo.
To search for food, the birds fly back and forth between fruiting trees, occasionally pausing to snatch up small animals such as squirrels. The male birds possess a ring around their eyes that is orange or red, while the ring remains white in females (11). The birds utilize their beaks to carry out various tasks such as gathering food, constructing the nest, sealing the nest, and feeding the chicks. Atop the beak is a casqued, a hollow structure resembling a helmet, which aids in amplifying their calls (10). Typically, they vocalize only when defending their territories against other breeding pairs (12).
Hornbills play a critical role in dispersing figs as they consume the entire fruit, including the seed, and then fly long distances to spread the seeds widely (11). They spend their entire lives in treetops but seek out old or dead trees with cavities to nest in. When it is time to lay eggs, the female uses food and droppings to seal the entrance (10). The female incubates the egg in the cavity for approximately 50 days, ensuring cleanliness by removing uneaten food and feces. The male hornbill provides food for both the female and the chicks (11).
The female bird leaves the nest after three months or 100 days, leaving the chicks to rebuild the nest covering and receive parental care for another three months (12). Eventually, as they grow, the chicks break out of the nest and begin flying. Found exclusively in Borneo and Sumatra, the Rafflesia flower is an incredibly rare and remarkable species. It holds the distinction of being the largest flower in the world, weighing up to 10kg (4). The growth process of a Rafflesia flower starts with a small bud and can take over a year for it to bloom.
Rafflesia plants are parasitic and do not have leaves or roots. Instead, they rely on their host vine for nourishment and support. The only part of the plant that is visible outside of the flower is made up of fungus-like tissue strands that grow within the Tetrastigma vine. The appearance of the flower is not meant to be beautiful; its five fleshy lobes resemble decomposing flesh with marbled red and white patterns. A chemical reaction causes the flower to emit a strong odor similar to rotting flesh. This smell attracts carrion-scavenging flies and beetles, which then help pollinate the plant.
The mature flower has a brief lifespan of approximately one week before it transforms into a withered, brown state, making it exceedingly rare and challenging to locate (4). The buds and blossoms contain elevated levels of tannin and phenols, which can be toxic if consumed in excessive quantities. It is noteworthy that humans utilize this flower in two distinct manners: aiding women in halting internal bleeding and reducing the size of the uterus after childbirth, and serving as an energizing beverage for men (5). Furthermore, a minuscule frog, acknowledged as one of the smallest globally, was recently discovered in Borneo. This diminutive amphibian, resembling the dimensions of a pea, was found inhabiting the vicinity of a mountain range within a distinctive pitcher-shaped plant (7).
The tadpole of the frog starts off at a size of only three millimeters, but it can reach a size of approximately nine to eleven millimeters when it reaches adulthood (8). Pitcher plants are carnivorous and use insects like ants as a source of nutrients, which are scarce in their typically poor and acidic soil. However, these plants do not harm frogs (9). Conversely, Nepenthes ampullaria plants obtain their nourishment from decaying organic matter that gathers in their pitcher (8). The frogs lay their eggs on the sides of the pitcher. Once hatched, the tadpoles thrive in the liquid that collects within the plant’s specially designed cavity for trapping insects.
The toad, which was last seen in the 1950s, is believed to have been affected by stream sedimentation caused by logging. Borneo, a significant landmass known for its abundant natural resources such as timber, natural gas, and petroleum (oil), also serves as a habitat for endangered creatures like orangutans, forest elephants, and rhinos. Furthermore, Borneo’s tropical rainforest houses a wide range of plant and animal species that are vital in establishing it as one of the planet’s biodiversity hotspots.
The Borneo Rainforest is a habitat for astonishing creatures like flying lizards and frogs (1) and constantly unveils novel species (2). Nevertheless, the rainforest confronts various environmental perils that jeopardize its survival. Forest fires, primarily triggered by logging to clear land and lightning storms (2), pose a significant threat to the island’s flora and fauna. Controlling these fires becomes exceedingly difficult due to the untamed nature of Borneo.
Historically, deforestation in Borneo was minimal due to infertile soils, unfavorable climate, and disease (1). However, deforestation started to increase during the mid-twentieth century with the establishment of rubber plantations, albeit with limited impact (3). By the 1970s, industrial logging rose as Malaysia depleted forests on the mainland. In the 1980s, significant expansion occurred with the construction of logging roads that allowed settlers and developers to access remote regions (2).
During the 1980s and 1990s, logging in Borneo reached unprecedented levels, resulting in harvesting of 60-240 cubic meters of wood per hectare (1). This extensive logging has adversely affected numerous animal species, including the Rhinoceros Hornbills that depend on trees for their survival. Consequently, these birds have suffered significant population decline, reproductive issues, and disruption to their overall way of life. Concurrently with the decline in logging activities, there was a growing interest in establishing oil palm plantations in Borneo (3).
Between the years 1960 and 2001, Malaysia experienced significant growth in its oil palm plantations. These plantations expanded from 60,000 hectares to over 3 million hectares, resulting in Malaysia becoming the largest producer of palm oil globally. At present, around half of Malaysia’s cultivated land is used for growing oil palm. In Sarawak, a state in Malaysia, there is approximately a total of 8.22 million hectares of land. Based on data from the state government, natural forests cover about two-thirds of this land area. The objective of the government is to safeguard roughly 8 percent of Sarawak’s natural forests while evenly distributing the remaining land between commercial forests and agriculture.
Over the past decade, the World Wildlife Fund (WWF) has discovered 361 animal species in Borneo’s forests that were destroyed for oil palm plantations. To safeguard the “Heart of Borneo” and its rainforest, Indonesia and other countries on the island have united at the Convention on Biological Diversity. Their objective is to manage resource usage and conserve what little biodiversity is left on the island (1).
The re-plantation of trees in specific areas aims to support forest growth and wildlife (2). Forests play a vital role in preserving the Earth’s environmental balance, and their absence would greatly affect the world. They are crucial for generating oxygen and valuable resources, highlighting the importance of discouraging deforestation and promoting plant growth. Additionally, forests serve as habitats for various animals, birds, and micro-organisms.
Moreover, rainforests have a vital function in maintaining worldwide climate stability and safeguarding against floods, droughts, erosion. Additionally, they offer valuable resources such as medicine and food. Our survival relies on the existence of rainforests to meet our daily necessities. Therefore, if we fail to effectively manage deforestation, we will encounter significant challenges including resource depletion, climate change, species extinction (including humans), and other pressing issues. The alarming transformations occurring in the Borneo Rainforest serve as a cautionary tale of what may transpire without prompt measures taken to conserve rainforests.
