Natural
Disaster
“Any
natural phenomenon which may cause loss of life and property for man is called
Natural disaster”. Volcanism, landslides, desertification, floods, cyclones,
earthquakes and forest fires are such natural phenomena which cause destruction
for mankind. Let us have a look on these natural disasters.
1. Volcanism
The formation
of molten rock material (Magma) inside the earth and the process of its coming
out on the earth surface is called Volcanism. The magma when comes on the
surface of earth is called lave and it burns and destroys everything that comes
in its way. Sometimes it comes out with an explosion and causes an earthquake.
Sometimes volcanic ash also comes out with lava and gases during volcanism.
This ash may rise in the atmosphere up to several miles and causes
environmental pollution.
Volcanism in
Pakistan
Pakistan is
fortunate that even lying in an active vibrant region, no dangerous and active
volcano lies within its boundaries. However some volcanic activates have been
traced in some places of Hindu Kush mountain ranges and Baluchistan.
Safety measures
To mitigate
loss of life and property in areas vulnerable to volcanism, an integrated
monitoring system of volcanoes has been adopted throughout the world. In case
of emergency, a warning is declared in the hazard zone to make people prepared
to combat the disaster.
2. Landslides
Down slope
movement of soil and weathered rock material under the influence of gravity is
called landslide”. It may create an impact in many ways. It may cause loss of
life and property. It may damage the construction severely. It may damage the
construction severely. It may block the roads and damage the communication
lines. It may block the flow of rivers i.e. the creation of Arababad Lake in
Gilgit is the result of river blockade by landslides. It may disturb the
agricultural productivity in the affected areas.
Landslides in
Pakistan
The northern
areas of Pakistan are affected by landslides during the rainy season. Due to
the construction of roads the slopes become unstable and vulnerable to
landslides. Karakoram highway which connects Pakistan to China often remains
blocked due to landslides. The unchecked tree cutting in mountainous areas of
Pakistan is also a main cause of landslides.
Safety measures
Methods of
slope stabilization can be adopted in areas vulnerable to landslides to reduce
their effects. Impacts of landslides can also be reduced by lowering the water
table underground, by improving the irrigation system, by avoiding
construction, by stopping unchecked tree cutting and by growing trees in the
affected areas.
3. Desertification
The extension
of deserts at the expense of cultivable lands is called desertification.
Although climate chances have always favored the process of desertification,
but human induced activities, especially after the industrial revolution are
very much responsible for increasing desertification. Due to this menace,
agricultural production and usable water resources are depleting and migration
of humans and wildlife from the affected areas in increasing. As a result
shortage of food, drought and increase in poverty at local level may occur.
Desertification
in Pakistan
Pakistan is
situated in warm and dry climatic region where the annual amount of rainfall is
less than 25 centimeters. Arid to semi-arid weather conditions prevail in
almost 80% area of Pakistan. The main cause of desertification in Pakistan is
unsafe and poor ways of cultivation which result in soil erosion, lapse of
fertility, and continuous drop in biodiversity.
Safety measures
To combat
desertification, tree plantation can favor in two ways. Firstly, it reduces
desertification by keeping weather conditions moderate. Secondly it acts as
hurdle to stop the spread of desertification towards cultivable areas. The use
of organic fertilizers can enhance the fertility of land. People can be made
aware about desertification and methods to stop it. Unchecked cutting of trees
should be discouraged and modern ways of cultivation and irrigation should be
adopted to stop desertification.
4. Floods
An overflow
of river water out of its channel, which may cause damage to the nearby
settlements, is called flood. It is considered a natural disaster because it
may be a cause of social and environmental degradation. It can damage any
constructional frame work, uncommented housing and buildings without deep
foundations. It may destroy bridges, roads, communication lines, crops, farms,
orchards, livestock and cultural monuments as well. Loss of lives especially of
women, children and aged can occur, along with the spread of diseases and
epidemics.
Floods in
Pakistan
Pakistan has
a natural system of rivers flowing out of the northern mountain ranges. These
mountain ranges are a home of huge glaciers outsides the polar areas.
Melt-water streams from glaciers feed these rivers. The upper plains of these
rivers are situated in the rainy monsoon region. In summers the monsoon rains
along with the melt water streams from glaciers cause heavy flooding in the
rivers of Pakistan.
Safety measures
Awareness
about the flood risks should be given to the people of areas vulnerable to
floods. Evacuation plan should be prepared to get people out of the area safely.
Electricity and gas supplies should be disconnected to avoid any accident.
Camps should be established in safe areas to provide shelter and food to the
affecters. Proper arrangements should be made for the return of affecters to
their homes. Efforts should be made on governmental and non-governmental side
for reconstruction of houses and rehabilitation of the affecters.
5. Cyclones
Cyclone is a
system of swirling winds which has low pressure area in the center. The winds
tend to circulate toward the center and produce rain with thunder and
lightning. Wind speed exceeds up to 200 kilometers per hours. The winds have
erosive power which destroys everything that comes in their way. Cyclones
produce continuous rainfall in a short period of time which may cause flooding
and loss of life and property. In coastal areas huge sea waves called storm
surges are generated which may cause destruction on a large scale.
Cyclones in
Pakistan
Arabian Sea
lies in the south of Pakistan. In Indian Ocean, this is an important area of
the origin of tropical cyclones. These cyclones affect the coastal areas of
Pakistan. Thatta and Badin in sindh, while jeewani, Gwadar and Lasbela in
Balochistan are the main areas affected by the cyclones. Inadequate
construction methods and inferior construction material, absence of laws of
land use, lack of awareness of the local people, lack of education and poverty
are the main causes of destruction caused by cyclones.
Safety measures
Construction
of resistant houses should be made possible. Forecast management system should
be established in areas vulnerable to cyclones. As soon as the warning is
given, arrangements should be made to shift the livestock and house hold items
to safe places. Evacuation system should be established and mobilization of
volunteers in the affected areas should be made possible. In case of
evacuation, the house should be sealed after disconnecting power supplies. A
risk map should be prepared about the estimation of extent and storage of
drinking water, food, candles, matches and first aid material should be made
possible. Keep in touch with radio and report to emergency rescue centers
established by the government.
6. Earthquakes
Sudden and
intense vibration of the earth crust is called Earthquake. As this is a sudden
movement without any pre-occurring symbols, prediction of earthquake is not
possible. Earthquakes destroy human settlements, buildings and infrastructure
i.e. bridges, roads, railway lines, pipelines, water tanks and communication
etc. indirect damages include fire, loss of water reservoirs, and landslides
etc. the most unrecoverable damage caused by the earthquake is the loss of
valuable lives.
Earthquakes in
Pakistan
Geologically
Pakistan lies in an active zone at the margin of three tectonic plates. Indian
plate is converging with the Eurasian plate in the north and Arabian plate in
the west. The geologic result of this convergence is the formation of
Karakoram, Himalayas and the Hindu Kush mountain ranges in the north and
northwest. This convergent boundary is also responsible for the occurrence of
earthquakes in Pakistan and adjacent areas.
