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Forests: Our Lifeline17One evening Boojho entered the

park with an elderly person. Heintroduced him to his friends.

Prof Ahmad was a scientist working inthe university. The children startedplaying while Prof Ahmad sat on abench in the corner. He was tired as hehad participated in the golden jubileecelebrations of the town. After a while,the children also came and sat aroundhim. They wanted to know about thecelebrations. Prof Ahmad told them thatafter the cultural programme, thesenior people discussed the town’sunemployment problem. A plan wasproposed to put up a factory by clearingan area of the forest just outside thetown. This would give the increasingpopulation of the town a chance to getjobs. The children were very surprisedwhen Prof Ahmad told them that manypeople had objected to this idea.

“This is because the forests serve asgreen lungs and water purifying systemsin nature”, Prof Ahmad explained. Thechildren were confused. Prof Ahmadrealised that the children had not visiteda forest. The children also wanted toknow more about the forest, so theydecided to visit it with Prof Ahmad.

17.1 VISIT TO A FOREST

One Sunday morning, the childrenpacked a few things like a knife, a handlens, a stick, a notebook and walkedtogether through a forest trail near avillage. On their way, they met Tibu, ayoung boy of their age group, of nearbyvillage, who was taking cattle for grazingalong with his aunt. He was very agile,running here and there to keep the herdtogether. When he saw the children,Tibu also started walking along withthem, while his aunt went on a differentpath. As soon as they entered the forestTibu raised his hand and signalled themto keep quiet because noise coulddisturb the animals living in the forest.

Tibu then took them to a place at aheight to show them the broad view ofthe forest. Children were surprisedbecause they could not see any land(Fig. 17.1). The different treetops hadformed green cover over the land. However,the cover was not uniformly green. The

Fig. 17.1 A view of a forest

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environment was peaceful and a coolbreeze was blowing. This made childrenquite fresh and happy.

While coming down, they got excitedon hearing a sudden sound of birds andsome noise from the top branches of thetrees. Tibu told them to relax since itwas a normal phenomenon here.Because of the children’s presence, somemonkeys had climbed higher up on thetrees where they disturbed the birds.Animals often give this type of warningcall to alert other animals. Tibu also toldthat many other animals like boar,bison, jackals, porcupine, elephants livein the deeper areas of the forest(Fig. 17.2). Prof Ahmad cautionedchildren that they should not go deepinto the forest.

Boojho and Paheli remembered thatthey have studied about forests as

Fig. 17.2 Some forest animals

Fig. 17.3 Forest as habitat

an example of a habitat in Class VI(Fig. 17.3). They could see now how theforest provides a home for many animalsand plants.

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The land where the children werewalking was uneven and covered withmany trees. Tibu helped them to identifysal, teak, semal, sheesham, neem,palash, fig, khair, amla, bamboo,kachnar (Fig. 17.4). Prof Ahmad pointedout that there are several other trees,shrubs, herbs and grasses in the forest.The trees were also covered with different

types of creepers and climbers. The sunwas barely visible through the leaves ofthe trees, making it quite dark insidethe forest.

Activity 17.1

Observe the various things in your homeand make a list of those which are madefrom material which may have beenobtained from the forest.

You might have many wooden itemson your list like plywood, fuel wood,boxes, paper, matchsticks, andfurniture. Do you know that gum, oils,spices, fodder for animals and medicinalplants are also some of the productswhich we get from the forest (Fig. 17.5).

Fig. 17.4 Some forest plants

Semal

Sheesham

Neem

Bambooo

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Fig. 17.6 Some crown shapes

Woodenstatue

Sheila wondered who would haveplanted these trees. Prof Ahmad repliedthat in nature trees produce enoughseeds. The forest floor providesfavourable conditions for them togerminate and develop into seedlings

Prof Ahmad asked children to lookup and observe how the branches of thetall trees look like a roof over the otherplants in the forest. He told them thatthis is called a canopy (Fig. 17.7).

Activity 17.2

Visit a forest or a park in yourneighbourhood. Observe the trees andtry to identify them. You can take thehelp of some elders or books on trees.List the characteristics of the trees thatyou observe, such as the height, shapeof leaves, crown, flowers, and fruits. Alsodraw the crowns of some trees.

Prof Ahmad pointed out that treeshad crowns of different types and sizes.These had created different horizontallayers in the forest. These are known asunderstoreys (Fig. 17.7). Giant and talltrees constituted the top layer followedby shrubs and tall grasses, and herbsformed the lowest layer.

“Would we see similar kind of treesin every forest?” — asked Boojho.Prof Ahmad said, “No, due to differentclimatic conditions there are variationsin the types of trees and other plants.The types of animals also differ fromforest to forest.”

Fig. 17.5 Forest products

Sealing wax

Gum

Catechu

and saplings. Some grow up into trees.He added that branchy part of a treeabove the stem is known as the crownof the tree (Fig. 17.6).

Honey

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other small animals on the bark of thetrees, plant leaves and on decayingleaves on the forest floor (Fig. 17.8). Theystarted making sketches of thesecreatures. The forest floor seemed darkcoloured and was covered with a layerof dead and decaying leaves, fruits,seeds, twigs and small herbs. Thedecaying matter was moist and warm.

Children picked up various seedsand leaves for their collection. Walkingover the dead leaf layer on the forest floorwas like walking over a spongy carpet!

Is the decaying matter always warm?Prof Ahmad suggested that the childrencould perform an activity to get ananswer to this question.

Activity 17.3

Dig a small pit. Put vegetable waste andleaves in it. Cover them with soil. Addsome water. After three days, remove the

Fig. 17.7 Canopy and under storeys in a forest

A few children were busy watchingbeautiful butterflies fluttering here andthere on the flowers of shrubs andherbs. They had a close look at thebushes. While doing that their hair andclothes had seeds and shrubs clingingto them.

They came across numerous insects,spiders, squirrels, ants and various

Understorey

Fig. 17.8 Forest floor

Canopy

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Fig. 17.9 Interrelationship of plant, soil and decomposers in a forest

upper layer of the soil. Does the pit feelwarm inside?

Paheli asked, “There are so manytrees here. Also, there are many forestlike this. What difference will it make ifwe cut some trees for a factory?”

Prof Ahmad said, “You have readabout autotrophs, heterotrophs andsaprotrophs. You have learnt how greenplants produce food. All animals,whether herbivores or carnivores,depend ultimately on plants for food.Organisms which feed on plants oftenget eaten by other organisms, and soon. For example, grass is eaten by

insects, which in turn, is taken by thefrog. The frog is consumed by snakes.This is said to form a food chain:Grass → insects → frog → snake → eagle.Many food chains can be found in theforest. All food chains are linked. If anyone food chain is disturbed, it affectsother food chains. Every part of theforest is dependent on the other parts.If we remove one component, say trees,all other components would be affected.”

Prof Ahmad asked children to pickup leaves from the forest floor andobserve them under a hand lens. Theyfound tiny mushrooms over the

Photosynthesis

SoilDecomposers

Oxygen

Carbon dioxide

WaterNutrients

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plants release oxygen through theprocess of photosynthesis. The plantshelp to provide oxygen for animalrespiration. They also maintain thebalance of oxygen and carbon dioxidein the atmosphere (Fig. 17.10). That iswhy forests are called lungs.

decaying leaves. They also saw an armyof tiny insects, millipedes, ants andbeetle on them. They were wonderinghow these organisms live there. Prof Ahmadexplained that apart from these animalswhich are easily seen, there are severalorganisms and micro-organisms thatlive in the soil. Paheli wondered whatmushroom and other micro-organismseat. Prof Ahmad replied that they feedupon the dead plant and animal tissuesand convert them into a dark colouredsubstance called humus.

You have learnt about humus inChapter 9. In which layer of the soilwould you find humus? What is itsimportance to the soil?

The micro-organisms which convertthe dead plants and animals to humusare known as decomposers. Thesemicro-organisms play an important rolein the forest. Soon, Paheli removed somedead leaves and discovered under thema layer of humus on forest floor. Thepresence of humus ensures that thenutrients of the dead plants andanimals are released into the soil. Fromthere, these nutrients are again absorbedby the roots of the living plants. “Whathappens if an animal dies in the forest?”Sheila asked. Tibu replied the deadanimals become food for vultures, crows,jackals and insects.” In this way, thenutrients are cycled. So, nothing goeswaste in a forest (Fig. 17.9).

Paheli reminded Prof Ahmad that hehad not explained why forests are calledgreen lungs. Prof Ahmad explained that

Fig. 17.10 Balance of oxygen and carbondioxide

Paheli reminded theirfriends that they have

studied photosynthesis inChapter 1.

The children saw clouds forming inthe sky. Boojho recalled what he hadlearnt about the water cycle in Class VI.Trees take in water from their roots andrelease water vapour into the airthrough evaporation.

If there were fewer trees, how will thewater cycle be affected?

Tibu told them that the forest is notjust home to plants and animals. Manypeople also live in the forest. Some ofthem may belong to different tribes. Tibuexplained that these people dependmostly on the forests. The forest provides

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them with food, shelter, water andmedicines. They have traditionalknowledge about many medicinal plantsin the forest.

While Boojho was drinking waterfrom a small stream, he saw some deercrossing the stream (Fig. 17.11). Theydisappeared into the bushes. The densebushes and the tall grass provideanimals with the food and shelter. Theyalso protect them from carnivores thatlive in the forest.

between various types of droppings.Prof Ahmad informed them that theforest officers could recognise thepresence of some animals in the forestby their droppings and footprints.

Boojho called every one and showedthem a large, decaying heap of animaldropping. Several beetles and grubswere feeding on the heap and a bunchof seedlings was sprouting. “Theseseedlings are of the herbs and shrubs.The animals also disperse the seeds ofcertain plants and help the forest to grow

Paheli remembered that shesaw a Pipal sapling on the

sidewall in her school. Can youhelp her to understand how this

would have happened?

Fig. 17.12 A sapling on a wall

Tibu then started looking closely atthe forest floor. Soon he called andshowed the children droppings of someanimals, and explained the difference

and regenerate. The decaying animaldung also provides nutrients to theseedlings to grow”, said Prof Ahmad.

After listening to this, Boojho notedin his notebook, “By harbouring greatervariety of plants, the forest providesgreater opportunities for food andhabitat for the herbivores. Largernumber of herbivores means increasedavailability of food for a variety ofcarnivores. The wide variety of animals

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helps the forest to regenerate and grow.Decomposers help in maintaining thesupply of nutrients to the growing plantsin the forest. Therefore, the forest is a‘dynamic living entity’ — full of life andvitality.”

It was about afternoon and thechildren wanted to go back. Tibu

suggested another route for going back.While they were going back, it startedraining. However, surprisingly, they sawthat the raindrops were not hitting theforest floor directly. The uppermost layerof the forest canopy intercepted the flowof raindrops, and most of the water wascoming down through the branches and

Fig. 17.13 Rainwater drips from the trees and seeps into the ground

Covered ground withdecaying material actslike a sponge

Rain

The root system helpswater to seep down inthe ground

The closed canopy andmany layers of vegetationslow down the speed ofraindrops

Transpiration and evaporation

Root system

Water table

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the stems of the trees. From the leavesit was dripping slowly over branches ofthe shrubs and herbs (Fig. 17.13). Theyfound that the ground was still dry. Afterabout half an hour, the rain stopped.They noticed that the layer of deadleaves over the forest floor appeared wetnow. But water did not stagnate in theforest.

Boojho thought that if it had rainedso heavily in his town, it would haveflooded the drains and roads.

What would happen if it rains heavilyin your town?

Prof Ahmad told them that the forestalso acts as a natural absorber ofrainwater and allows it to seep. It helpsmaintain the water table throughout theyear. Forests not only help in controllingfloods but also help maintain the flowof water in the streams so that we get asteady supply of water. On the otherhand, if trees are not present, rain hitsthe ground directly and may flood thearea around it. Heavy rain may alsodamages the soil. Roots of trees normallybind the soil together, but in theirabsence the soil is washed away oreroded.

The children spent an hour at Tibu’svillage on their way back. The weatherof the village was quite pleasant. Villagerstold them that due to the surroundingforest, they receive good rainfall. The airalso remained cool. Noise pollution, toois less because the forest absorbs thenoise of the nearby highway.

The children learnt about the historyof the village. It surprised them that the

villages and the agricultural fields ofthat area were created after clearing theforest about sixty years ago. Tibu’sgrandfather told them that when he wasyoung, the village was not as large as itwas now. It was also surroundedby forests. Construction of roads,buildings, industrial development andincreasing demand of wood createdpressure on the forests and it startedvanishing. He was not happy that theforest adjoining their village is notregenerating and is on the verge ofdisappearing due to overgrazing ofanimals and indiscriminate felling oftrees. Prof Ahmad said that if we didthings wisely we could preserve forestsand environment as well as havedevelopment.

Children prepared a few pictures toshow the consequences of such anevent.

At the end of the visit, Prof Ahmadasked children to sum up theimportance of forests. The childrenwrote: Forests provide us with oxygen.They protect soil and provide habitat toa large number of animals. Forestshelp in bringing good rainfall inneighbouring areas. They are a sourceof medicinal plants, timber and manyother useful products. We must preserveour forests.

What would happen if forestsdisappear?

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1 If forests disappear, theamount of carbon dioxide inair will increase, resulting inthe increase of earth’stemperature.

2 In the absence of trees andplants, the animals will notget food and shelter.

3 In the absence of trees, thesoil will not hold water, whichwill cause floods.

4 Deforestation will endangerour life and environment.Think, what we can do topreserve our forests.

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What you have learnt

We get various products from the forests surrounding us.

Forest is a system comprising various plants, animals andmicro-organisms.

In a forest, trees form the uppermost layer, followed by shrubs.The herbs form the lowest layer of vegetation.

Different layers of vegetation provide food and shelter for animals,birds and insects.

The various components of the forest are interdependent on oneanother.

The forest keeps on growing and changing, and can regenerate.

In the forest, there is interaction between soil, water, air andliving organisms.

Forests protect the soil from erosion.

Soil helps forests to grow and regenerate.

Forests are the lifeline for the forest-dwelling communities.

Forests influence climate, water cycle and air quality.

Exercises

1. Explain how animals dwelling in the forest help it grow and regenerate.

2. Explain how forests prevent floods.

3. What are decomposers? Name any two of them. What do they do in theforest?

4. Explain the role of forest in maintaining the balance between oxygenand carbon dioxide in the atmosphere.

5. Explain why there is no waste in a forest.

6. List five products we get from forests?

Keywords

Canopy

Crown

Decomposers

Seed dispersal

Soil erosion

Understorey

Deforestation

Humus

Regeneration

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7. Fill in the blank:

(a) The insects, butterflies, honeybees and birds help flowering plantsin .

(b) A forest is a purifier of and .

(c) Herbs form the layer in the forest.

(d) The decaying leaves and animal droppings in a forest enrich the .

8. Why should we worry about the conditions and issues related to forestsfar from us?

9. Explain why there is a need of variety of animals and plants in a forest.

10. In Fig. 17.15, the artist has forgotten to put the labels and directions onthe arrows. Mark the directions on the arrows and label the diagramusing the following labels:

clouds, rain, atmosphere, carbon dioxide, oxygen, plants, animals, soil,roots, water table.

11. Which of the following is nota forest product?

(i) Gum

(ii) Plywood

(iii) Sealing wax

(iv) Kerosene

12. Which of the followingstatements is not correct?

(i) Forests protect the soilfrom erosion.

(ii) Plants and animals ina forest are notdepedent on oneanother.

(iii) Forests influence theclimate and watercycle.

(iv) Soil helps forests togrow and regenerate.

Fig. 17.15

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13. Micro-organisms act upon the dead plants to produce

(i) sand (ii) mushrooms (iii) humus (iv) wood

Extended Learning — Activities and Projects

1. The Department of Environment is to decide whether some portion of aforest in your area could be cleared for a housing complex. Write a letterto the department explaining your point of view as a concerned citizen.

2. Visit a forest. Here is a list of points that would make your visit morefruitful.

(a) Make sure that you have permission to go into the forest.

(b) Make sure that you can find your way around. Get a map and goalong with some one who is familiar with the area.

(c) Keep a record of the things you see and do. Observations makethe visit interesting. Sketches and photographs are useful.

(d) You may record bird calls.

(e) Collect different kinds of seeds or hard fruits like nuts.

( f ) Try to recognise various types of trees, shrubs, herbs, etc. Makelists of plants from different places in the forest and of differentlayers. You may not be able to name all the plants, but it is worthrecording and seeing where they grow. Make a record ofapproximate heights of plants, crown shape, bark texture, leafsize, and flower colour.

(g) Learn to recognise the animal’s droppings.

(h) Interview the forest officials and the people of surrounding villages and other visitors.

You must never collect birds’ eggs, and their nests should never bedisturbed.

You can read more on the following website:

www.wild-india.com

Did you know?

In India the area under forest cover is about 21% of the total area. It hadsteadily been falling since independence. But people now seem to haverealised the importance of the forest cover. Reports suggest that the areaunder forest cover has slightly increased in recent years.

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