Forests are considered as one of the top 5 natural resources on Earth. Have you had your breakfast? Drank a glass of water? Taken medicine for fever? Sat on a chair? Done a hand-drawing? Forest products are a vital part of our daily lives in more ways than we can imagine. Many aspects of our lives are directly or indirectly linked to forests, even though we may not always make the connection.
In this lesson, we shall look at what exactly is a forest, how wonderful are they to us, what do they give us, and should we worry about their future?
A large area filled with many trees is called a forest. There is more to forests than just a massive collection of trees. It is a natural, complex ecosystem, made up of a wide variety of trees, that support a massive range of life forms. Apart from trees, forests also include the soils that support the trees, the water bodies that run through them, and even the atmosphere (air) around them. Forests grow in almost every part of the world. Deserts, some prairies, and mountain tops, and the North and South poles are the only places bare of forests.
The main thing to know about forest and woodland habitats is that they are areas that have a lot of trees pretty close to each other. Woodlands are a little more open than forests - woodlands have space to let a bit of light in between trees, while forests have so many trees that it's actually pretty dark when you walk around.
There are two basic types of trees that make up most forests: hardwoods and softwoods.
Hardwoods have wide leaves and grow fruits. Examples include oaks and maples. They are often deciduous, meaning they shed their leaves in fall every year. However, some hardwoods, like mahogany trees, keep their leaves all year. Hardwood forests grow in places with temperate (mild) or tropical (hot) weather.
Softwoods have cones and needles rather than fruits and wide leaves. Examples include pines and redwoods. They do not lose their needles each year. Many softwoods are known as evergreens because their needles remain green throughout the year. Softwood forests often grow near mountains and in cool regions.
Many forests contain several different heights or layers of plants. And, as different animals are often found within each layer, the diversity of animals is often related to plant diversity in the forest.
Imagine, for a moment, standing in a sun-filtered stand of a dense forest. You will see different layers of plants:
Forests exist in dry, wet, bitterly cold, and swelteringly hot climates. These different forests all have special characteristics that allow them to thrive in their particular climate. Broadly speaking, there are three major types of forest zones that are separated according to their distance from the equator. These are:
Tropical rainforests grow around the equator in South America, Africa, and Southeast Asia. They have the highest species diversity per area in the world, containing millions of different species. They have a rainy and dry season. They are characterized by high temperatures, abundant rainfall, 12 hours of sunlight a day - all this promotes the growth of many different plants. Broadleaf trees, mosses, ferns, palms, and orchids all thrive in rainforests. The trees grow very densely together and the branches and leaves block most of the light from penetrating the understory. Many animals adapt to life in trees — such as monkeys, snakes, frogs, lizards, and small mammals — are found in these forests.
Temperate forests - These occur in North America, northeastern Asia, and Europe. There are four well-defined seasons in this zone including winter. Deciduous — or leaf-shedding — trees make up a large proportion of the tree composition in addition to some coniferous trees such as pines and firs. The decaying fallen leaves and moderate temperatures combine to create fertile soil. Common tree species are oak, beech, maple, elm, birch, willow, and hickory trees. Common animals that live in the forest are squirrels, rabbits, birds, deer, wolves, foxes, and bears. They are adapted to both cold winters and warm summer weather.
Boreal forests - Boreal forests, also called taiga, are found between 50 and 60 degrees of latitude in the sub-Arctic zone. This area contains Siberia, Scandinavia, Alaska, and Canada. Trees are coniferous and evergreen.
Boreal forests
Forests are home to 80% of the world's terrestrial biodiversity. These ecosystems are complex webs of organisms that include plants, animals, fungi, and bacteria. Forests take many forms, depending on their latitude, local soil, rainfall, and prevailing temperatures. For example, coniferous forests in colder regions are dominated by cone-bearing trees like pines and firs; and temperate forests contain deciduous trees such as oaks, maples, and elms, that turn beautiful shades of orange, yellow and red in the fall.
The most biologically diverse and complex forests on earth are tropical rainforests, where rainfall is abundant and temperatures are always warm.
Forests also play a critical role in mitigating climate change because they act as a carbon sink—soaking up carbon dioxide and other greenhouse gases that would otherwise be free in the atmosphere and contribute to ongoing changes in climate patterns.
The importance of forests cannot be underestimated. We depend on forests for our survival, from the air we breathe to the wood we use. Besides providing habitats for animals and livelihoods for humans, forests also offer watershed protection, prevent soil erosion, and mitigate climate change. Many important natural resources come from the world’s forests. Forests provide food, wood, fuel, natural fibers, and other materials. These resources may be made into furniture, shelter, paper, clothing, medicines, and many other products.
They are home to 80% of the world’s terrestrial biodiversity, and they also form the source of livelihood for many different human settlements, including 60 million indigenous people.
After oceans, forests are the world’s largest storehouses of carbon. They absorb harmful greenhouse gases that produce climate change.
Forests can act as either carbon sources or carbon sinks.
The net balance of all of these carbon exchanges determines whether a forest is a carbon source or sink. Yet, the carbon source/sink balance is as dynamic as it is complex.
Forests are known as the lungs of the planet. This is because they supply a huge amount of Earth’s oxygen, which animals need to breathe. The trees of a forest give off oxygen as part of a process called photosynthesis. Forest trees also help to protect soil from erosion. They block the forces of wind and water that wear away the land. In addition, forests offer a peaceful place for hiking, camping, bird-watching, and exploring nature.
Yet, despite our dependence on forests, we are still allowing them to disappear.
Deforestation
But forests are being destroyed and degraded at alarming rates. Deforestation is when humans remove or clear large areas of forest lands and related ecosystems for non-forest use. These include clearing for farming purposes, ranching, and urban use. In these cases, trees are never re-planted. Since the industrial age, about half of the world’s original forests have been destroyed, and millions of animals and living things have been endangered. Despite the improvements in education, information, and general awareness of the importance of forests, deforestation has not reduced much, and there are still many more communities and individuals who destroy forest lands for personal gains.
Why do humans clear forest lands?
For all the reasons above, the trees cut are usually very well developed trees that have taken many years to mature. When they are cut they break down younger trees as they fall to the ground, leaving that area heavily degraded.
The Amazon, the planet’s largest rainforest, lost at least 17% of its forest cover in the last half-century due to human activity. In Indonesia, the island of Sumatra has lost 85% of its forests—primarily due to conversion for oil palm and pulp plantations—and a similar level of destruction is taking place on the island of Borneo. Deforestation also undermines the important carbon sink function of forests. It is estimated that 15% of all greenhouse gas emissions are the result of deforestation.
Forest degradation is different from deforestation. Degradation is the destruction or reduction in the quality of specific aspects of forests. Prolonged degradation can wipe out a forest. Degradation can result in a decrease in tree cover, changes in their structure, or a reduction in the number of species that can be found there. If acid rain destroys trees in a vast area, it can be called forest degradation.
Forest degradation can be caused by factors such as:
Forest fires - In many forests, fires usually occur from time to time. Forest fires always start in one of two ways - naturally caused or human-caused. Natural fires are generally started by lightning, with a very small percentage started by spontaneous burning of dry fuel such as sawdust and leaves. On the other hand, human-caused fires can be due to any number of reasons. Forest fires wipe out many thousands of acres each year all over the world. This has effects on biodiversity and the economy as well.
Climate change - Extreme climates can also cause degradation. Prolonged droughts and dry conditions reduce the tree cover and dry out water bodies running through them. They force many animals to migrate and reduce the quality of forest ecosystems.
Pests and diseases - Pest or disease outbreak can also destroy the vegetative cover in forest lands.
Degraded forests can often be restored.
It is the breaking of large, contiguous, forested areas into smaller pieces of the forest; typically these pieces are separated by roads, agriculture, utility corridors, subdivisions, or other human development.
Sometimes, we are overwhelmed by the extent of damage humans have caused, and we are not sure if one individual can make an impact.
Yes, you can. There are millions of people just like you who are learning about the issue and taking little steps to help. Here are some of the ways you can help too:
Humans will not survive without forests.
