All the three major categories of organisms viz. Producers, consumers and decomposers are abundantly present in a tropical forest ecosystem. Primary producers are the autotrophs that can capture the light energy and manufacture their own food. The major producer plants in a tropical forest are ferns, bananas, vines, epiphytes and grasses. Consumers are the heterotrophs that cannot synthesize their own food and are dependent on other organisms. They are further classified into primary, secondary and tertiary consumers. The primary consumers include herbivore animals, birds and insects including macay, parrot, sloth, bats, etc. These organisms directly feed on green plants (producers). Primary consumers are in turn eaten by secondary consumers (carnivorous animals) such as jaguar, ocelot and snakes. Further, tertiary consumers like eagle eat up the secondary consumers. The third category of organisms is of decomposers. They break down the organic matter present in the other dead organisms. The dead and decaying tissue of both the plants and animals is decomposed by micro-organisms and fungi (Raven & Johnson, 2002).
Apart from the biotic components, abiotic components also shape the ecosystem. Abiotic factors are the non-living chemical and physical components of the environment that affect the ecosystem. Abiotic factors present in a tropical forest ecosystem are water, air (wind and gases), soil and light (Raven & Johnson, 2002).
Several types of interactions are present amongst the organisms in a tropical forest ecosystem. Predator-prey relationship is one of the most significant interactions between the organisms. This interaction is exemplified by a macay eating fern and a jaguar eating the macay. Apart from this, the other significant interactions are commensalism, parasitism, mutualism and competition. Commensalism is a symbiotic relationship in which one organism is benefitted, and the other is not benefitted/not harmed. For example, a frog gets water, and shelter from a vermiliad and the latter is unaffected. In parasitism, one organism is benefitted while the other is harmed as is the case of lice and ticks on higher animals. Both the organisms are benefitted in the case of mutualism. For example, algae growing on a sloth’s fur. Here, the algae gets a substratum to grow and the sloth camouflages. Plants competing for water and sunlight are examples of competition in a tropical rain forest (Raven & Johnson, 2002).
Numerous food chains constitute the food web in a tropical forest. For example, a fern (primary producer) is eaten away by a sloth (primary consumer). This sloth may in turn be eaten by a jaguar (secondary consumer). Originally, the fur of the sloth is of brown color, however, due to the mutual interaction between the sloth and the algae, it appears greenish (algae inhabits its fur). Green color helps the sloth to blend with the tree canopies and makes it invisible to predators. Another example of a food chain in the tropical forests is of parrots eating fruits and snakes eating parrots. Like sloths, parrots have also adapted themselves to the tropical forest ecosystem. They have a strong curved and long beak as compared with other birds. It helps them to crack the nuts and fruit shells. Many of the primary consumers in the tropical forests (such as sloth and macay) are eaten up by jaguar (the secondary consumer). It has adapted itself to climb the trees so that it may pounce from trees on its prey (WorldlyWise, 2007).
Owing to the human activities, tropical forests have changed drastically. Tropical forests may act as pollution recipients, pollution sources or pollution sinks. Human beings dump the agricultural and industrial wastes in these forests and, therefore, they are pollution recipients. Other human activities such as forest clearance for cash crops cause the release of greenhouse gases into the environment and contribute to global warming. Furthermore, global warming negatively impacts the forests as warmer temperatures causes accelerated growth of tree-destroying pests.
Environmental pollution affects all forms of life in a tropical forest. Industrial chemicals are depleting the ozone layer, and the natural UV screen action is reduced. UV rays from the sun pose several harmful effects on the plants and higher animals of the tropical forests. Acid rain slows the growth of forest trees and may cause the leaves to fall off. It may also deplete the vital nutrients and minerals of the soil and seriously affects aquatic life (Raven & Johnson, 2002; Irina, 2008).
References
Gray, Irina. (2008). Environmental pollution and tropical rainforests. Tropical-Rainforest-Animals.com. Retrieved from http://www.tropical-rainforest-animals.com/Environmental-Pollution-Tropical-Rainforests.html
Raven, Peter & Johnson, George. (2002). Biology 6th Edition. United States of America: McGraw and Hill.
WorldlyWise. (2007). How have animals adapted to the conditions of tropical rain forests? Retrieved from http://worldlywise.blogspot.in/2007/10/how-have-animals-adapted-to-conditions.html
