Afforestation Programby PR Sarkar
A few hundred years ago, many of the desert regions in the world were full of trees and wildlife. The deserts have spread due to:
- tree felling by local people and commercial interests
- the depletion of the subterranean water
Many problems occur with the disappearance of trees.
- The carbon dioxide content in the air rises as there are fewer plants to absorb the carbon dioxide which is constantly being expired into the atmosphere.
This results in changes in the atmosphere and the environment, causing climatic warming. If there is a rise of only a few feet in the level of the oceans, many major cities in the world, including Calcutta, could be flooded.
- The catchment areas are destroyed, rivers reduce their flow of water or dry up.
Also, the area around the rivers is transformed into a desert, as in the case of the Nile and the Ganges.
- The organic processes in the soil are halted.
Without the trees, micro-organisms die. This causes the worms to die. This causes the organic matter to break down and cease to retain water. Hence, the soil-making process is stopped.
Central Ráŕh was full of lush flora, wildlife and large rivers three thousand years ago. Even 30 years ago there were many trees and dense forests in the region. Now there are hardly any trees, few wild animals, and the rivers have almost dried up. For 8 months of the year, the region is dry.
The soil is hard and barren, contains few worms or micro-organisms and little organic material, which acts like a sponge to retain the rainwater.
The annual rains wash away much of the topsoil that still exists, hence the remaining soil has become coarse and sandy. As a result, the whole region is subjected to flash floods and severe soil erosion.
The banks of all water systems should be covered by dense forests because the roots of the trees retain water.
When the water-table subsides, the roots of the trees slowly release water. Hence, a pond surrounded by trees will never run dry.
The foliage of the trees also minimizes evaporation. Their leaves have very small pores which attract clouds, so the trees help to increase the rainfall.
Only 100 years ago, there were large rain forests in Ráŕh. Back then in the Manbhum district, the rainfall was 70-80 inches per year. Now it is hardly 40-45 inches.
A scientific programme of afforestation should include 2 aspects.
To transform this depleted and undernourished environment, a massive, scientific 2-phase afforestation programme has to be launched.
- Fast growing trees which grow to their full height in 6 months to 2 years and provide valuable green cover should be planted:
- sisir (Albezzia lebbeck)
- sisoo (Dalbergia)
- bakphul (Sesbania grandiflora)
- large screwpine (Pandanus andamanensium)
- drumstick (Moringa oleifera)
- red sandalwood (Santalum album)
- agave (sisal, Agave americana)
- Diospyros discolor
- chámal (Eterocarpus chaplasa, Roxb.), a wild variety of jackfruit found in north east India.
- Slow growing trees like teak, which also provides green cover and can be harvested after 30 years or so, should be planted.
The fast growing trees can be cut after three years, providing an additional source of income for local people. If this approach is followed, the ecological balance in the area will be restored very quickly.
In addition to this approach, some selected plants need to be grown in desert regions to check the process of desertification.
For example, in dry, sandy areas we can grow jojoba which produces seeds that yield oil which can be substituted for diesel oil. Different cactii, Acacia catechu or Acacia arabica can also be grown.
Afforestation is the only solution to desertification.
- Phase 1: Fast-growing trees should be planted.
Trees which grow to their full height in six months to two years and provide dense green cover should be selected.
- Phase 2: Trees which take longer to grow but also provide dense green cover should be planted. This approach will quickly restore the ecological balance of a region.
Afforestation must be carried out both intensively and extensively. The best approach is to plant both fast growing and slow growing trees together.
- Planting only slow growing trees is uneconomic because we will have to wait 30-100 years to get the desired result.
- Planting only fast growing trees will not provide any long term benefits.
So both intensive and extensive afforestation should be done immediately. After reaching maturity, the trees can be selectively cut and sold.
Afforestation should be carried out on the banks of ponds, canals, dams, lakes, rivers and reservoirs.
For example, babula [Acasia arabica Willd.] or kheyer [Acasia catechu Willd.] should be planted. In between these trees we can plant bukphul [Sesbania grandiflora Pers.], and in between these, Indian rosewood.
The reason for this is that bukphul grows very fast and within five years it will be a tall tree, but babula takes a little longer to grow. Indian rosewood grows very slowly but it lives a long time.
Thus, first bukphul will grow fast and attract rain which will help the other trees to grow. When it has fully matured after five or seven years it can be cut, and by this stage we will have a dense forest of Indian rosewood trees.
These trees are very useful in other respects also. For example, bukphul leaves increase the milk supply in cows, while thread can be produced from the leaves and stem.
Indian rosewood trees increase the rainfall and hold water in their roots. The flowers provide a plentiful supply of honey, the leaves can be used to make plates, the sap is used to produce gum for the incense industry, and the tree may be used in sericulture to produce tasar silk.
The seeds are also edible and are taken by poor people, while the honey has medicinal use and economic value, so it can earn foreign exchange as an export commodity. Piyasal [Pterocarpus marsupium Roxb.] can also be planted in between Indian rosewood trees if need be. In this way, step by step, we have to proceed.
Scientific crop management is also an essential aspect of water conservation.
For example, a field of barley needs less water than a field of vegetables. A barley field next to a vegetable field can get 25% of the water from the latter as runoff.
Fruit trees can store a lot of water in their roots. They should be planted along river banks and near paddy fields to help conserve water.
After the paddy harvest at Ánanda Nagar, for example, the water flows into the two rivulets:
- the Alkananda
- the Paragati
This leaves the fields dry. After a short time, the rivulets also dry up as their supply of seepage water from the fields stops.
To solve this problem, fruit trees should be planted beside the rivulets. The water stored in the roots of the fruit trees will keep the soil moist and fertile. Care should be taken so that the branches of the fruit trees do not block the sunlight from the crops.
If this system is followed, when the paddy is cut and the fields are drained of water, the rivulets will remain flowing. If fruit trees are planted along the banks of a river, it will always retain water.
Foolish human beings, however, have cut down all the trees along the river banks, so now many rivers have dried up.
Who would believe that 150 years ago large boats used to travel along the Mayuraksi Rriver in Bengal?
Today it is a small river, and in the rainy season small boats only ply along it.
The forests around the river have all gone.
The forest trees contain water in their root systems and release it in a controlled way which enables the rivers to flow regularly.
Due to deforestation, these rivers are now drying up, and consequently there is less rainfall.
The inner spirit of our water conservation programme is that the amount of existing surface water should be immediately doubled. But it is preferable if it is increased tenfold.
This can best be done by a decentralized approach to water management which increases the depth, the area, or both, of water storage systems.
The first step is to increase the depth of those ponds, tanks, dams, lakes, rivers and reservoirs which are already being used for storing water.
The second step is to increase the area of these storage facilities, while the third step is to increase the plantations around them.
How can these plantations be increased by a factor of ten?
By increasing the number of rows of plants around each water storage system five times, and by reducing the distance between each plant by half.
In addition to this, many new small-scale ponds, tanks, dams, lakes and reservoirs should also be constructed. As a general rule, surface water should always be utilized in preference to subterranean water.