We all know that rainforests are big, beautiful places filled with a huge variety of plant and animal life, but do we know how they affect us? Or maybe more importantly, how we affect them. In this written plan I will guide you step by step through the basic knowledge of a typical rainforest, before moving onto more serious issues, such as how people affect them, and what problems they face. I will also provide suggestions as to how these problems can be solved.
Characteristics of a tropical rainforest
Rainforests are the earth’s most biologically diverse ecosystems. They are typically situated along the equator, in Asia, Africa and Latin America, where the climate remains warm and humid all year round. Rainfall can reach up to 2,400 mm annually. Despite holding up to 50% of the earth’s animal species, they only cover about 7% of the earth’s land surface. The soil consists of pure sand, with a layer of humus (plant and animal remains), and is generally very fertile.
Plant life in a rainforest is typically divided into four layers: the emergent layer, the canopy, the understory, and the forest floor.
The emergent layer:
The emergent layer contains the tallest trees, who tower as much as 60 meters above the forest floor. Their trunks can measure up to 5 meters around. Most of these trees are hardwood evergreens, with broad leaves. The leaves are thick and waxy, to help retain water. Sunlight is plentiful.
The canopy is the primary layer of the rainforest and covers everything below it. It consists of a dense community of trees that rise to about 45 meters. They have broad leaves, to shed rainwater and discourage the growth of mosses. The leaves filter out about 80% of the light from above, and prevent it from reaching the forest below.
The understory only gets about 2-5% of the sunlight available to the canopy. This limited light encourages the plant residents to devise unique ways to survive, such as the solar-collecting dark green leaves. The plants here seldom grow to above 3.5 meters in height.
The forest floor:
Less than 2% of the sunlight is available here. Aside from that, the humidity goes up to 95%. The few plants that live here have to tolerate deep shade. The ground is littered with decaying plant and animal remains.
It is impossible to name all the animal species inhabiting the rainforests, as they contain up to 50% of the world’s animal species. There is a great abundance of animals of all sizes, but the majority would consist of insects living in the rainforest.
Like plants, different animals also live in different layers of the forest. Birds inhabit the treetops, whilst the larger mammals, such as jaguars and elephants tend to stay of the forest floor. There are also many mammals that live in trees, such as the sloth and the members of the primate family. Insects can be found everywhere.
There are up to two thousand indigenous people living in the rainforest, with their own language and culture. They live off the natural resources provided by the forest. However, it is not just the people inhabiting the rainforest that affect it and consequently, ‘live off’ it. There are also many companies who make money by cutting down and selling tropical hardwood. This has devastating effects not only for the tree population, but also for the wildlife and for the people living in the forest, whose homes are being destroyed.
The destruction of the rainforests is a great problem. Not only for the inhabitants of the rainforests, but worldwide. The trees in the rainforest are essential to the well being of our planet. Without them, the sea level and temperatures would rise, due to global warming. This has already started. A Savannah climate will prevail in Amazonia, without the trees and with the global warming. Tribes of people will be rendered homeless and without resources to help them survive, as well as thousands of species of insects and animals.
Currently, about 15 hectares of rainforest is destroyed annually. At this rate, within thirty to fifty years, there will be no rainforest left. Trees that are hundreds of years old will be destroyed in a matter of days.
Many people profit from the destruction of the forests. This, naturally, is why they do it. In order to stop them, they must be compensated and offered alternatives. There must also be no more consumer demand for products made of tropical hardwood.
Initiative is already being taken. There are:
– International agreements to conserve ecology.
– Projects offering education to lessen farmers and forest laborers.
– Alternatives for tropical hardwood being used.
– Consumer actions to promote the sale of hardwood with a certificate.
– Discoveries of products that make living forests more profitable than the once-only trade in tropical hardwood.
With these initiatives being taken, and hopefully the co-operation of the rest of the community, I am confident that the destruction of the rainforests will cease, and they will once more thrive as they did before.
Oceans and Wetlands
What are wetlands?
Wetlands are areas of standing water that support aquatic plants. Marshes, mangroves, swamps, and bogs are all considered wetlands. They are usually freshwater ecosystems, but are not classified as such because of various wetlands such as salt marshes that have a high salt concentration.
They are the homes of a variety of plant species adapted to the very moist and humid conditions called hydrophytes. Many species of amphibians, reptiles, and birds can be found in wetlands.
Threats to wetlands:
Deforestation is causing wetlands such as mangroves to gradually disappear, taking its inhabitants with them. Up to 50% has been cleared away to make way for shrimp and fish farms. The fish farms in turn threaten the mangrove fish by the discharge of nutrients and pesticides, the escape of non-native species, the spread of diseases, and damage to natural habitat.
How can we help to preserve the wetlands?
To preserve the wetlands, the governments should create nature reserves around them so that they will not be destroyed. Fish farms should not be made near the reserves, to prevent the problems they cause.
What are oceans?
Oceans are great bodies of water. There are seven major oceans on our planet, the largest being the pacific. They are home to a huge variety of aquatic life. Water covers up to 2/3 of the earth’s surface. They can be thousands of square kilometers large and several kilometers deep.
Ocean life consists of many animals of all types and sizes, including fish, mammals, reptiles, crustaceans and others. They vary greatly in size, from the microscopic plankton to the gigantic blue whale.
Mammals living in the ocean include seals, dolphins and whales, whilst reptiles consist of primarily turtles. There are many different species of fish, some with special adaptations according to their diet and what part of the ocean they live.
Oceanic plant life is often very colorful, and also often carnivorous, as light is limited underwater so photosynthesis is illogical and inefficient. Aquatic plant life includes anemones, feather dusters, barnacles, hydroids, seaweed, kelp, algae, coral and many others.
Plants such as anemones serve as habitats for fish, whilst algae is eaten by them.
Many of the ocean inhabitants are in danger due to over-fishing and water pollution. Thousands fish and birds die from oil spillages annually.
In addition to that, the coral found in the sea is also being destroyed and damaged. Fishermen damage coral with their nets and anchors, or when they fish using poison or dynamite. Divers break pieces off of it by accident, or take the most beautiful pieces home for their aquarium.
What can be done?
There have been actions taken towards preventing these problems, such as international agreements on safe ocean transportation of oil and other pollutants, and regulations regarding the amount of fishing being done and limiting it. Chemical dispersants are used to break up oil spills when they occur, so that the oil concentration isn’t as high in a small area. This lessens the damage done by the spill.