Forest can be defined as a large area of land covered with trees and bushes, either growing wild or planted for some purposes. Forestry, on the other hand, is the study and management of forests and forest resources. In other words, it is the art of planting, tending and managing forests, including the utilization of their products. Silviculture is the study of forest trees and other related trees.
Common Forest Trees
Common trees usually found in the forest are Iroko, Obeche, Mahogany, Nigerian walnut, Ebony, Camwood, Opepe, Afara, Teak and Abura.
FOREST RESERVES IN NIGERIA
Forest reserves are large areas of land where plants, either growing naturally or planted, are specially preserved by government for specific purposes.
Some forest reserves in Nigeria are:
- Mamu River Forest Reserve in Anambra State.
- Omo Forest Reserve in Ogun State.
- Afi River Forest Reserve in Cross River State.
- (Okomu Forest Reserve in Edo State.
- Anara Forest Reserve in Kaduna State.
- Shasha River Forest Reserve in Ogun State.
- Sakpoba Forest Reserve in Edo State.
- Zamfara Forest Reserve in Zamfara State.
- Sanga River Forest Reserve in Plateau State.
- Awba Hills Forest Reserve in Oyo State.
IMPORTANCE OR USES OF THE FOREST
Forest is very important for several reasons. It is very important for government to encourage the planting of trees because of its usefulness in the following ways.
- Provision of Food: Forest including savanna provides food such as fruits, bush meat and vegetables.
- Provision of Fuel: Dead forest wood serves as firewood or source of fuel used for cooking and other purposes.
- Provision of Medicinal Herbs: The forest also provides medicinal herbs used by local healers and pharmaceutical industries.
- Provision of Employment: Forest provides employment for some people, e.g ., forest guards and those involved in lumbering.
- Forest Serves as Wind-break: Forest, especially in the northern part of Nigeria, serves as windbreak, thereby reducing the speed of wind and controlling wind erosion.
- Formation of Rain: Forests, because of their cool environment, help in the condensation of water vapour, resulting in the formation of rain.
- Prevention of Soil Erosion: Forest helps to absorb water splash on the soil. Also due to vegetative cover, soil erosion is prevented.
- Addition of Nutrients to Soil: Forest adds nutrients or improves the fertility of the soil through the decay of fallen leaves.
- Home of Wild Animals: Forest serves as the home of all wild animals like lion, tiger, antelope, rabbit and snakes.
- Forest Serves as Tourist Centre: Forest, because of its beautiful scenery, does serve as tourist centre.
- Provision of Foreign Exchange: Forest provides foreign exchange earnings for the country through the export of timber and its by-products.
- Provision of Timber: Forest provides timber for furniture and other domestic and industrial constructions.
- Provision of Pulp: Forest provides pulp used for tissue and paper making.
- It Beautifies the Environment: Forest trees planted around homes, industries and offices help to beautify the environment.
- Reduces Atmospheric Pollution: Forests help in the purification of the air by removing carbon dioxide and adding oxygen to the atmosphere during photosynthesis.
- Sources of Raw Materials: Forest provides raw materials such as gum, resins, ropes, dyes, fibres, rubber, palm produce, oil seeds for both domestic and industrial purposes.
MANAGEMENT OF THE FOREST
In order to ensure the continuous supply of timber from the forest, the following management practices should be adopted:
- forest regulations;
- selective exploration;
- taungya system.
1) Forest Regulations: These are laws promulgated by government in the form of edicts, decrees and bye-laws to prevent people from exploiting or indiscriminate tapping of forest resources. These regulations, therefore, ensure the preservation of forest resources.
Forest regulations in Nigeria include:
- the prohibition of bush burning;
- ban on indiscriminate cutting of timber trees;
- encouraging people to plant trees;
- ban on collection of leaves and firewood from the forests;
- ban on farming in forest reserves;
- ban on the cutting down of underaged trees.
- people are to obtain licences so as to secure the permission to enable them to cut down trees for human needs. The felling quantity should be based on the number of forest stands which must be determined before felling.
2) Selective Exploration
Selective exploration is the process of cutting or harvesting only matured trees in a forest. It is a way of concentrating certain selected species of timber in a forest reserve. The system allows for the harvesting of older trees while the younger ones remain as cover to the surface of the forest. It is the legal felling of trees based on certain criteria such as maturity and species.
Advantages of Selective Exploration
- It ensures the concentration of selected species of timber in a forest.
- It protects the soil from erosion.
- It ensures the continuous supply of timber.
- It serves as a revenue base for the government.
- It prevents indiscriminate felling of timber by giving licences to saw millers by state forestry division.
- It also prevents illegal felling of trees and farming by using forest guards to police the forest.
- Undesirable species of timber are eliminated by this method.
3) Deforestation: Deforestation is the continuous removal of forest stands (trees) either by bush burning or indiscriminate felling without replacing them. Economic trees such as Iroko, Obeche and Mahogany are cut down so that they can be used for various purposes such as furniture like tables, chairs and doors. Uncontrolled deforestation should never be allowed. The rate of deforestation should be reduced to the barest minimum because of its adverse effects.
Causes of Deforestation
Deforestation can be caused for many reasons which include:
- Unfavourable Climatic Factors: Persistent and prolonged drought can lead to death of forest species. Also, wind blasts can destroy vegetation on its path.
- Man’s Farming Activities: Man’s farming activities can cause forest destruction through the use of forest land for crop production or grazing livestock, practising of bush fallowing or shifting cultivation which progressively leads to deforestation because the short fallow periods do not allow for sufficient forest regeneration.
- Timber Exploitation: The practice of selective elimination of certain tree species ina natural forest causes deforestation. Also, the exploitation of timber for furniture, export, etc can cause deforestation.
- Mining/Industrialization: Forest trees are destroyed when the land is cleared for excavation for mining minerals. Also, petroleum exploration and siting of industries involve clearing of forest.
- Natural Disasters: Fire is the most serious problem to which forests are exposed, especially during the dry season. Bush burning is caused by fire used by farmers. Such fire may extend to the forest, thereby destroying tree species. Other natural disasters which can cause deforestation include landslide, earthquakes, volcanic eruptions and prolonged flooding.
- Government Policies: Government inadvertently introduces policies that can encourage felling of fuel woods and timber exploitation.
Effects or Disadvantages of Deforestation
Deforestation has some effects or disadvantages on the environment. These are:
- Deforestation encourages or increases soil erosion.
- It leads to loss of organic matter, resulting in the loss of soil fertility.
- It reduces the amount of rainfall in the area, or it causes the destruction of watershed.
- It decreases soil moisture retention.
- It increases the leaching of plant nutrients.
- Deforestation destroys the micro-climate, and warms up the environment.
- It also reduces the forest fauna (wild life) population in the area concerned.
- It may lead to desert encroachment as sand particles are more likely to drop in areas without trees.
- It depletes the supply of forest produce (raw materials) to industries, e.g. timber.
4) Regeneration: Regeneration is the process of forest regrowth after it has been exploited. It is a deliberate government policy in the restoration of deforested area after exploitation to balance the ecosystem.
It can occur either by re-growing from old stumps or deliberate planting of new forest seedlings in a deforested area. It may be natural or artificial.
Types of Regeneration
There are two main types of regeneration. These are:
- Natural Regeneration: In natural regeneration, there is regrowth of new plants from old stumps. Under favourable environment, there exists the growth and development of new tree or volunteer trees from old stumps.
- Artificial Regeneration: This involves the natural planting of new forest seedlings in a deforested area. In other words, forest trees are established deliberately in a plantation.
Advantages of Natural Regeneration
- It is less expensive when compared with artificial regeneration.
- It does not require formal stages in plantation establishment.
- It brings about the stabilization of natural ecosystem in the area of its establishment.
- It does not require special management skill.
5) Afforestation: Afforestation is the process of establishing forest plantations in any area. It involves the complete removal of natural vegetation before planting new forest species.
In Nigeria, it is popularly referred to as tree planting campaign in which two seedlings of trees are recommended to be planted to replace any one plant harvested. Early stages of afforestation may include taungya farming (which is the planting of trees and crops on the same piece of land) to maximise the use of land and protect seedlings.
Advantages of Afforestation
Afforestation has many advantages:
- It leads to addition of organic matter, resulting in an increase in soil fertility.
- It provides a regular supply of raw materials, e.g ., timber for industries.
- It prevents desert encroachment.
- It increases the forest fauna (wild life) in the area concerned.
- It builds up the micro-climate and cools down the environment.
- It prevents the leaching of plant nutrients.
- It increases soil moisture retention.
- It increases the amount of rainfall in the area.
- It helps to build up the soil structure.
6) Taungya System: Taungya system is defined as the planting of arable crops at early stages of forest establishment and the arable crops are harvested before the trees form canopies. In other words, taungya farming is a management practice which involves the planting of food crops and some forest trees at the same time until the canopy of the trees close up. It is a system which involves the integration of agriculture with forestry.
Conditions Necessary for the Practice of Taungya System
The conditions that may favour the practice of taungya system include:
- Scarcity of Land: Taungya system can easily be practised where land is scarce.
- Over-population: Land becomes scarce where there is over -population which can lead to the practice of the system.
- Unemployment: Mass underemployment or unemployment does lead people to practise taungya system.
- Government Policies: Government can put in place policies which will make people practise taungya system.
- Low Standard of Living: This factor does force people to resort to the practice of taungya system as a means of alternative way of increasing their standard of living.
- Granting of Incentive: Incentives such as loans to farmers can help them to take part in additional farming.
Advantages of Taungya Farming
- Variety of crops are harvested.
- There is the availability of crop produce throughout the year.
- When leguminous crops are used, the beneficial effect of root nodules increases soil fertility for the benefit of the forest trees.
- Where land is scarce, the farmer has a piece of land to cultivate.
- The young forest trees receive direct and indirect attention from the farmer.
- It increases the income of the farmer.
Farmers derive the benefit of:
- using available fertile land for farming;
- increased standard of living;
- accessibility to forest products, e.g. drywood for fuel;
- employment of farmers in plantation activities other than initial raising of forest crops.
Foresters derive the benefit of:
- reduced cost of establishing plantation;
- more land is under forest cover;
- weed control;
- enrichment of soil nutrients when leguminous food crops are planted.
Disadvantages of Taungya Farming
- Reluctance in Releasing Fertile Soil: The forestry sector may be reluctant in releasing their fertile land to the agricultural sector for farming.
- Cultivation of Selected Crops: The system only allows the farmers to rear animals and cultivate biennial crops in the forest reserves.
- Competition Between Crops and Trees: Since crops and trees are grown together on the same piece of land, competition for space, water, nutrients, etc will exist between crops and forest trees.
- Monotony of Operations: The practice of taungya farming may be monotonous as the farmer performs the same operation every season.
- Inability of Some Crops to Survive: Most crops cultivated under taungya farming may not survive due to the invasion of some insects in the forest reserve.