Fires & Forest Fires Dr. Sammeta Govardhan

1 Radio serial on understanding & Managing Disaster Episode No. XVIII
Fires & Forest Fires
-
Dr. Sammeta Govardhan
Science Communicator
[email protected]
Cell No.9949038471
…. Signature tune ….
….Appropriate music ….
Dr.Anvesh
:
Hello … sister … we are having one week holidays from tomorrow onwards.
Dr.Bharathi
:
Hi… that’s good .. you can come over here and spend the holidays with us.
Dr.Anvesh
:
O.K. … this night, I will start and reach your place by tomorrow morning..
Dr.Bharathi
:
We will await your arrival. After you come over here we can plan where to go and
how to spend the time.
Dr.Anvesh
:
OK … OK … than see you tomorrow morning.
<><> Appropriate music <><>
Dr.Bharathi
:
Children get up. Dr.Anvesh is coming this morning to spend a week days with us.
Vignan
:
That’s wonderful … we can go to places in his car…
Uthsuka
:
Yes … I too will like to spend holidays with uncle …
Dr.Anvesh
:
Hai … Vignan and Uthsuka. How are you. How the studies going, hope you are
doing well.
Vignan
:
Yes, uncle … both myself and sister are going well. We always stood first in the
class, in curricular and extra curricular activities.
Vignan
:
Uncle … let us go to picnic in the nearly forest. Erect a tent and spend the whole
day, watching trees, birds, wild animals and nature beauties.
Dr.Anvesh
:
That’s a very good idea, if everybody is agreeing, I don’t have any objection to go
on picnic.
Dr.Bharathi
:
Its OK. Let us spend tomorrow in the forest.
Vignan
:
Oh … it will be wonderful. Tomorrow is picnic day.
<><><>
Dr.Anvesh
:
We are approaching the Forest, be careful while moving in the forest. We will
move as a group.
Dr.Bharathi
:
Children … listen to the advice given by uncle. We have to be very very careful,
otherwise we may fall pray to wild animals.
Vignan &
Uthsuka
:
O.K. mummy, don’t’ worry. We will move as per your advise.
2 Vignan
:
Who is that man? Let us meet him, he may advice us on what to see in the forest.
Dr.Anvesh
:
Namasthe sir, how are you?
Forest Range
Officer
Uthsuka
:
:
Namasthe, I am Ashwin Kumar, Incharge of the Forest Range. I can be of some
help if you want to know about forest.
Sir, please tell us about forest fires in India and the consequences there upon.
FRO
:
With pleasure. The most common hazard in Forests is forest fire. Forest fires are
as old as the forests themselves. They pose threat not only to the forest wealth but
also to the entire regime to fauna and flora, seriously disturbing the bio-diversity
and ecology and environment of a region. During summer, when there is no rain for
months, the forests become littered with dry senescent leaves and twigs which
could burst into flames ignited by the slightest spark. The Himalayan Forests,
particularly, Garhwal Himalayas have been burning regularly during the last few
summers, with colossal loss of vegetation cover of that region.
Vignan
:
What causes the forest fires?
FRO
:
Forest fires are caused by Natural causes as well as man made causes. First let us
know about natural causes.
Many forest fires start from natural causes such as lighting which set trees in fire.
However, rain extinguishes such fires without causing much damage. High
atmospheric temperatures and dryness (low humidity) offer
favourable
circumstances for a fire to start. With regards to man made causes – fire is caused
when a source of fire like naked flame, cigarette or beedi, electric spark or any
source of ignition comes into contact with inflammable material.
Uthsuka
:
Can we classify the forest fires?
FRO
:
Yes, why not – Forest fire can be broadly be classified into three categories.
- Natural or controlled forest fire.
- Forest fires caused by heat generated in litter and other biomes in summer
through carelessness of people and
- Forest fires purposely caused by local inhabitants.
Vignan
:
What about types of forest fire?
FRO
:
There are two types of forest fire
(i)
Surface fire and (ii) Crown fire
Let us first discuss about surface fire –
A forest fire may burn primarily as surface fire, spreading along the ground as the
surface litter on the forest floor and is engulfed by the spreading flames.
Whereas crown fire, the other type of forest fire is a crown fire in which the
crown of trees and shrubs burn, often sustained by a surface fire. A crown fire is
particularly very dangerous in a coniferous forest because resinous material given
off burning logs burn furiously. On hill slopes, if the fire starts down Hill, it
spreads up fast as heated air adjacent to slope tends to flow up the slope spreading
flames along with it. If the fire starts up hill, there is less likelihood of it spreading
downwards.
Uthsuka
:
Can you throw information on vulnerable places?
3 FRO
:
Yes, why not. The youngest mountain ranges of Himalayas are the most vulnerable
stretches of the world susptible to forest fires. The forests of western are more
frequently vulnerable to forest fires as compared to those in Eastern Himalayas.
This is because forests of Eastern Himalayas grow in high rain density. With large
scale expansion of pine forests in many areas of the Himalayas the frequency and
intensity of forest fires has increased.
Vignan
:
Mummy I am feeling hungry..let us take food and rest for a while, after wards we
can continue the forest tour.
Dr.Bharathi
:
OK.. let us take rest underneath a tree beside the canal and take food.
Dr.Anvesh
:
Agreed..Mr.Ashwin Kumar will join us too. I think.
FRO
Uthsuka
:
:
It’s very kind if you, I don’t have any objection for it.
So let us eat together.
(Appropriate music)
FRO
:
Thank you very much for delicious lunch…
Dr.Bharathi
Vignan
:
:
You are welcome. It is a pleasure to share what we brought with you.
Shall we begin our forest visit?
FRO
:
Oh.. no problem in the morning itself we have covered a lot. The remaining
part we can cover now.
Uthsuka
:
Sir, please through light on the precautious to be taken to prevent forest fires.
FRO
:
That’s very good on your part Uthsuka. I will tell you the important precautions
against fire.
- To keep the source of fire or source of ignition separate from combustible
and inflammable material.
-
To keep the source of fire under watch and control. Not allow combustible
or inflammable material to pile up unnecessarily.
-
And to stock the same as per procedure recommended for safe storage of
such combustible or inflammable material.
-
To adopt safe practices in areas near forests viz., factories, coal mines, oil
stores, chemical plants and even in household kitchen.
Vignan
:
Is that all?
FRO
:
No… No… I am telling you one by one. Three more are these.
-
To incorporate fire reducing and fire fighting techniques and equipment
while planning a building or coal mining operation.
-
In case of forest fires, the volunteer teams are essential not only for fire
fighting but also to keep watch on the start of forest fires and sound an
alert.
-
and last but not the least is to arrange fire fighting drills frequently.
4 Dr.Bharathi
:
What are the impacts of forest fires in Biological environment?
FRO
:
Forest fires also pose serious health hazards by producing some and noxious
gases, as the events in Indonesia after the forest fires on the islands of Sumatra
and Borneo in 1977 has shown. The burning of vegetation gives off not only
carbon dioxide but also a host of other, noxious gases, such as carbon
monoxide, methane, hydrocarbons, nitric oxide, nitrous oxide, that lead to
global warming and ozone layer depletion. Consequently, thousands of people
suffered from serious respiratory problems due to these toxic gases. Burning
forests and grass lands also add to already serious threat of global warming.
Recent measurement suggest that biomass burning may be a significant global
source of methyl bromide, which is an ozone depleting chemical.
Uthsuka
:
Can you site some notable wild fires in the world?
FRO
:
Oh yes … - Landes Forest 1949 wild fire in south West France, 50,000
hectares of forest land were burnt and 82 people killed.
- 2003 Portuguese wild fires.
- Peshtigo fire 1871 most losss of life in a US wild fire.
- Great Fire of 1910 in the USA shaped 20th Century wild fire policy.
- 2009 SE Australia bush fires.
- 2010 Bolivian forest fires.
- 2010 Russian wild fires.
- 2013 Beaver creek fire.
Vignan
:
What is a wild fire?
FRO
:
Well that is a very good question – A wild fire is an uncontrolled fire in an
areas of combustible vegetation that occurs in the country area.
Other names such as brush fire, bush fire, forest fire, desert fire, grass fire, bill
fire, peat fire, vegetation fire and veldfire may be used to describe the same
phenomenon depending on the type of vegetation being burned.
Wild fires are quasi – natural hazards. This is because they are caused by
human activity as well.
The four major natural causes of wild fire ignition are lighting. Volcanic
eruption, sparks from rock falls and spontaneous combustion.
Usthuka
:
Is the wild fire effected by weather?
FRO
:
Yes, Heat Waves, droughts, cyclical climate change such as El Nino and
regional weather patterns such as high – pressure ridges can increase the risk
and alter the behavior of wild life dramatically. Years of precipitation followed
by warm periods can encourage more wide spread fires and longer fire seasons.
However, one individual element does not always cause an increase in wild fire
activity.
Vignan
:
What about fire ecology?
FRO
:
Wild fires are common in climates that are sufficiently moist to allow the
growth of vegetation but feature extended dry, hot periods.
5 Uthsuka
:
How the plants adapt to this situation?
FRO
:
Plants in wild fire – prone ecosystems often survive through adaptations to their
local fire regime. Such adaptations include physical protection against heat,
increased growth after a fire event and flammable materials that encourage fire
and may eliminate competition. For example, plants of the genus Eucalyptus
contain flammable oils that encourage fire and hard sclerophyll leaves to resist
heat and drought, ensuing their dominance over less fire – tolerant species.
Uthsuka
:
Will atmospheric effects contribute to wild fire?
FRO
:
The vertical lift of a severe thunderstorm or pyrocumulonimbus can be
enhanced in the area of wild fire.
Vignan
:
How can we prevent the wild fires?
FRO
:
Wild fire prevention refers to the preemptive methods of reducing the risk of
fires as well as lessening its severity and spread. Effective prevention
techniques allow supervising agencies to manage air quality, maintain
ecological balance, protect resources and to limit the effects of future
uncontrolled fires. The prevention policies must consider the role that humans
play in wild fires, since 95% of forest fires in Europe are related to human
involvement. Sources of human caused fire may include arson, accidental
ignition, or uncontrolled use of fire in land – clearing and agriculture such as
the slash and burn farming in South East Asia.
Uthsuka
:
Thank you very much sir, you have given a extensive picture of forest fires,
mummy evening is approaching, shall we make a move?
Dr.Bharathi
:
Oh…sure on the way we can visit our relative Mr.Vijay.
Vignan
:
Who … Mr.Vijay? who works in Fire Department?
Dr.Bharathi
:
Yes, you remember him very well.
Uthsuka
:
Then we can have some information on fires… what do you think brother?
Vignan
:
Good idea, our knowledge will increase with that, sure, we will visit.
(Appropriate music)
[Bell rings – a man opens the door]
Vijay
:
What a surprise, most unexpected?
Dr.Bharathi
:
We all went to nearly forest and spent the morning. On the way we thought of
visiting you.
Vijay
:
Oh.. you are welcome.. how are you Vignan and Uthuska?
Vignan
:
Namasthe.. we are doing fine uncle.
Uthsuka
:
Uncle … we want to know about fire for our science project, can you explain?
Vijay
:
It is a pleasure. Well… scientifically speaking .. Fire is the rapid oxidation of a
material in the exothermic chemical process of combustion, releasing heat, light
and various reaction products.
6 Vignan
:
What a flame?
Vijay
:
The flame is the visible portion of the fire. Fire in its most common form can
result in conflagration, which has the potential to cause physical damage
through burning. Fire is an important process that effects ecological systems
around the globe. The positive effects of fire include stimulating growth and
maintaining various ecological systems. Fire has been used by humans for
cooking, generating heat, light, signaling and propulsion purposes.
Uthsuka
:
Kindly throw some light on negative effects?
Vijay
:
Definitely… the negative effects of fire include hazard to life and property,
atmospheric pollution, and water contamination. If fire removes protective
vegetation, heavy rainfall may lead to an increase in soil erosion by water.
Also, when vegetation is burned, the nitrogen it contains is released into
atmosphere, unlike elements such as potassium and phosphorus which remain
in the ash and are quickly recycled into soil. This leads to loss of fertility.
Vignan
:
Uncle, how the fire can be extinguished?
Vijay
:
Fire can be extinguished by removing any one of the elements of fire
tetrahedron. consider a natural gas flame such as from a stove top burner. The
fire can be extinguished by
-turning off the gas supply, which removes the fuel source.
- covering the flame completely, which smoothens the flame as the combustion
both uses the available oxidizer and displaces it from the areas around the flame
with CO2.
- Application of water, which removes heat from the fire faster then the fire can
produce it.
- Application of a retardant chemical such as Halon to the flame, which retards
the chemical reaction itself until the rate of combustion is too slow to maintain
chain reaction.
Dr.Bharathi
:
What about fire ecology?
Vijay
:
Every natural ecosystem has its own fire regime and the organisms in those
ecosystems are adapted to or dependant upon that fire regime. Fire creates a
mosaic of different habitat patches each at a different stage of succession.
Different species of plants, animals and microbes specialize in exploiting a
particular stage, and by creating these different types of patches, fire allows a
greater number of species to exist within a land scape.
Dr.Bharathi
:
How the fire is controlled?
Vijay
:
The ability to control fire was a dramatic change in the habits of early humans.
Making fire to generate heat and light made it possible for people to cook food,
increasing the variety and availability of nutrients. The heat produced would
also help people stay warm in cold weather, enabling them to live in cooler
climates. Fire also kept nocturnal predators at bay. Fire has also been used for
centuries as a method of torture and execution, as evidenced by death by
burning as well as torture devices.
Uthsuka
:
The fires destroy living beings?
7 Vijay
:
Yes… Hot fires destroy plants and animals, and endanger communities. This is
especially a problem in the forests of today where traditional burning is
prevented in order to encourage the growth of timber crops. The cool fires are
generally conducted in the spring and autumn. They clear undergrowth,
burningup biomass that could trigger a hot fire should it get too dense.
Uthsuka
:
How about protection and prevention measures?
Vijay
:
Fire fighting services are provided in most developed areas to extinguish or
contain uncontrolled fires. Trained fire fighters use fire apparatus, water supply
resources such as water mains and fire hydrants or they might use A and B class
foam depending on what is feeding the fire. Fire prevention is intended to
reduce sources of ignition. Fire prevention also includes education to teach
people how to avoid causing fires. Model building codes require passive fire
protection and active fire protection system to minimize damages resulting
from a fire.
Vignan
:
Uncle you have given a lengthy picture of fire, its negative effects,
extinguishing methods, fire ecology and its control. Thank you very much.
Uthsuka
:
This will be very much useful to prepare my science project on Fires & Forest
Fires.
Vijay
:
You are welcome.
(Appropriate music)
CONCLUSION
Author:
Dr.Sammeta Govardhan
3-13-156/1
Kumarpally, Hnamkonda
Warangal – 506 001, Telangana.
Cell no. 99490 38471