Chapter 9 – Disaster Management
Answer the following in your own words.
1. Explain the relation between continuous rains and landslide. Give reasons.
Ans:
(i) A rapid rise in groundwater levels in response to heavy rainfalls causes an increase in groundwater pore pressure.
(ii) This increased groundwater pore pressure leads to decreased stability of slope material.
(iii) Also, degradation of rocks (weathering) and decreased stability of slope material leads to incidents of landslides.
(iv) Heavy rainfalls lead to soil erosion which is one of the causes of landslides.
2. Prepare a chart showing ‘Do’s’ and ‘don’ts’ at the time of earthquake.
Ans:
Do’s:
(i) Take cover under furniture and hold on until the shaking stops.
(ii) Find a safe spot away from windows and glass.
(iii) Reassure others and avoid panic.
(iv) Shield yourself with your arms if cover is unavailable.
(v) Follow emergency instructions from authorities.
Don’ts:
(i) Stay indoors to avoid debris.
(ii) Don’t use elevators; they may malfunction during shaking.
(iii) Don’t stand under doorways; take cover under furniture instead.
(iv) Avoid fire hazards from matches or candles.
(v) Prevent injuries from shattered or sharp objects.
3. What are the specifications of an earthquake-proof building ?
Ans:
(i) The primary aim of the earthquake-proof buildings is the safety and security of the occupants and assets.
(ii) IS 456, IS 1893 and IS 13920 from Bureau of Indian Standards provide code of conduct for general construction as well as earthquake resistant design of a structure.
(iii) Following are the specifications of earthquake-proof building:
(a) Such buildings are separated from lower land.
(b) Only standard devices having detailed experimental data on the performance are used in construction.
(c) The materials used in constructions are less in weight, preferably wooden materials.
4. Explain the effects of landslide.
Ans: Following are the possible effects of landslides:
(i) Rivers get flooded and change their paths.
(ii) Displacements of waterfalls and formation of artificial water reservoirs occur.
(iii) Loss of life and financial losses on a large scale take place due to collapse of trees, buildings, rocks on sloppy areas and collapsing on low-lying areas.
(iv) Landslides affect the traffic. Landslides destroy plant life on it.
5. Is there any relation between dam and earthquake ? Explain.
Ans:
(i) Dams (water reservoir) could cause earthquakes due to the change in stress because of the weight of water, or by increased groundwater pore pressure.
(ii) The increased groundwater pore pressure leads to decrease in the effective strength of the rock under the reservoir.
(iii) The extra water pressure created in the micro-cracks and fissures in the ground under and near dams can cause earthquakes.
2. Give Scientific reasons.
1. It is safer to find shelter under things like a bed, table at the time of earthquake.
Ans:
(i) An earthquake causes sudden vibrations of the earth’s surface, which lead to the falling of heavy objects like cupboards, fans, ceilings, etc.
(ii) Taking shelter under a bed or table would protect individuals from severe head injuries caused by falling objects.
(iii) Therefore, it is safer to find shelter under things like a bed or table at the time of an earthquake.
2. In monsoon, don’t take shelter near hillside.
Ans:
(i) Hillside areas are susceptible to landslides during heavy rains.
(ii) The sloping area of the hill may slide along with the flow of rainwater, and a person may get trapped under the mud, rocks, soil, or trees.
(iii) Hence, in monsoons, we should avoid taking shelter near hillsides.
3. Don’t use lifts at the time of earthquake.
Ans:
(i) A lift (or elevator) is an electrically driven device used to carry people or goods in tall buildings.
(ii) In the case of an earthquake, the electric power supply may get cut off, causing people to get trapped in lifts for a long period of time.
(iii) If the earthquake is strong, then it could cause the elevator system to fail completely and fall to the bottom of the shaft, causing severe injuries.
(iv) There are also chances of fire being caused by electric sparks.
(v) Therefore, lifts should not be used during earthquakes.
4. The foundation of earthquake-proof building is separated from other land.
Ans:
(i) The seismic design strategy involves separating the building from the foundation to absorb shocks occurring due to an earthquake. This is known as base isolation.
(ii) The foundations of earthquake-resistant buildings are designed to reduce seismic forces by changing the stiffness of the structures.
(iii) Therefore, the foundation of an earthquake-proof building is separated from other land.
3. If a crowd gathers at the place of earthquake, what would be the difficulties in relief work?
Ans: Following difficulties would be faced if crowd gathers at the place of earthquake:
(i) Disaster management team may find it difficult to reach people affected by the earthquake.
(ii) Path of ambulance and other vehicles required for rescuing injured people would be blocked and they may not reach the affected area on time.
(iii) Incidences like stampede may also occur if the disaster management team fails to manage the crowd. This stampede may also lead to loss of human lives.
4. Make a list of the institutes and organizations who provide help for disaster management. Collect more information about their work.
Ans:
(1) National Disaster Management Authority (NDMA):
NDMA is India’s apex body for disaster management. It formulates policies, plans, and guidelines for disaster management, and coordinates disaster response and recovery efforts.
(2) National Disaster Response Force (NDRF):
NDRF is a specialized force trained in disaster response and relief operations. It plays a crucial role in rescuing and assisting affected communities during various types of disasters.
(3) Indian Red Cross Society:
The Indian Red Cross Society provides emergency assistance, disaster response, and health services during disasters. It collaborates with various government agencies to offer relief.
(4) Indian Space Research Organisation (ISRO) – Disaster Management Support (DMS) Programme:
ISRO’s DMS program uses satellite data for disaster management. It provides imagery and information for monitoring and responding to natural disasters.
(5) SEEDS (Sustainable Environment and Ecological Development Society):
SEEDS focuses on disaster risk reduction and response. They work to build disaster-resilient communities by providing training, capacity-building, and disaster preparedness programs.
(6) United Nations Office for the Coordination of Humanitarian Affairs (OCHA):
OCHA coordinates international humanitarian response efforts during crises. It works to ensure that humanitarian aid reaches those in need and provides timely information and coordination.
(7) Doctors Without Borders (Médecins Sans Frontières):
This medical humanitarian organization provides medical care and aid to populations affected by disasters, epidemics, and conflicts. They operate in various regions worldwide.
(8) World Food Programme (WFP):
WFP is the food assistance branch of the United Nations. It provides food aid to populations affected by disasters, conflicts, and emergencies, preventing hunger during crises.
(9) Mercy Corps:
Mercy Corps is an international humanitarian organization that focuses on helping communities affected by disaster and conflict. They provide emergency relief, support livelihoods, and promote resilience.
(10) International Federation of Red Cross and Red Crescent Societies (IFRC):
IFRC is a global humanitarian organization that operates in coordination with national Red Cross and Red Crescent societies. They provide disaster response, relief, and recovery services.
5. Make a survey of your school according to the plan of disaster management and write the pointwise information.
Ans: Students must do this on their own.
6. Are there any possible places of landslide in your area? Collect information from experts.
Ans: Students must do this on their own.
7. With the help of following picture, explain your role in the disaster management.
Ans:
(i) From the picture it can be seen that a person seems to have received information about the prediction of some kind of impending or upcoming disaster in his area.
(ii) His role in disaster management would be to spread correct and reliable information to others in his locality, making them aware of the situation and informing them about the precautions that they must take in order to stay safe and minimize losses during the disaster situation.
(iii) He should immediately collect resources like fire extinguishers, food packs, first aid, etc. that may be required if any adverse situation arises during the disaster.