Unit 2 IMPACTS/ REPERCUSSIONS OF HAZARDS

2.1 Classification of Disaster impacts

1. Social Impacts due to loss of lives

2. Health impacts

3. Socio-economic impacts

4. Environmental impacts

5. Ecological impacts

2.2 Impacts of Floods

Apart from loss of life (human and cattle) and damage to property, the devastating effects of floods include sense of insecurity and fear in the minds of people living in the flood plains. Other effects include

agony of survivors,
spread of epidemics,
non-availability of essential commodities, and medicines,
loss of dwellings
damage of crops
damage of drinking water wells
damage of public utilities

2.3 Impacts of Droughts

The impact of droughts may be economical, environmental and social

Economic impacts

Loss of crops, which means loss to farmers, and increase od price
Loss of timber causing losses to timber industry
Loss of businesses in fisheries, farm equipment, fertilizers, food processing, etc
Loss in water transportation
Reduced hydro-power generation

Environmental impacts

Loss of fish and wild life habitat
Loss of foood and drinking water for humans and wild animals
Migration of men and animals
Increased stress to endangered species, leading to extinction of loss of biodiversity
Loss of tress and vegetation
Loss of reservoirs, lakes, ponds and wetlands
Increase in ground water depletion and land subsidence
Reduced water quality
Increased soil erosion due to winds
Degraded landscape
Increased number of fires and loss of forest and human habitat

Social impacts

Large scale migration of people, resulting in loss of income, and mental and physical stress
Health and nutritional problems
Famine and hunger
Loss of human and animal life due to heat, hunger and depressions

2.4 Impact of landslides and avalanches

Block river flow, roads and communication lines
Immense loss to agricultural production and land area
Causes series caualities
Causes flooding which worsens situation

2.5 Impacts of cyclones

Physical damage: The severest damage is caused by the floods, wind forces and storm surges, land-slides. Weak and light-weight structures razed to the ground.
Casualities and public health: Cyclones cause great damage to health. Viral infections are caused by violent winds. Epidemic diseases such as diarrhoeas, malaria, cholera, typhoid, jaundice, etc spread very fast.
Effect on water supplies: Flood water also causes havoc by contaminating surface waters and piped water supplies, and results in acute shortage of drinking water.
Damage to crops and food supplies: Cyclones accompanied by violent winds and torrential rains cause damage to the standing crop and stocked food grains in the low-lying areas. Sea water flooding increase the salinity and make the soil unsuitable for cultivation purpose.
Damage to communication and transport: The cyclonic winds completely smash the commmunication and trnasport system.
Damage to essential services: The cyclonis winds badly damages and disrupt the essential services like electricity, sewage disposal and water supply.

2.6 Impacts of Volcanic eruptions

The impacts of Volcanic eruptions are usually local or regional. Moreover, the changes in ecosystems and environment are reversible over passage of time

Due to volcanic eruption, mammals, birds and many small terrestrial animals are wided out.
The gases, smoke and ash unleashed from the volcano cause sever heat in the area with temperatures exceeding even 800°C.

2.7 Impacts of Earthquakes

Earthquakes destroy large cities in a matter of seconds, and may take thousands of human lives.

In most earthquakes of high magnitudes or of shallow depth of focus,

all communications are destroyed,
ground fissures erupt ground water, and
large scale flooding caused due to obstructed drainage, building collapse

Damage beyond instantaneous damage

Collapse of transportation network: Due to damaged roads, rails and airports
Collapse of medical facilities: Too many people are injured to various degrees
Collapse of electricity, water supply and food supply
Collapse of communication systems
Secondary causes leading to loss of lives

Hunger
Epidemic
Cold
Shock & trauma
Lack of medical attention

2.8 Impact of mining

Mining is a man-made activity. Thus, it can be planned, controlled, and mitigated with systematic efforts. Mining is of two types: 1. Surface or open cast mining, 2. Under-ground mining. Both these types involve the following environmental impacts. (Link)

1. Air pollution: Dust from mining causes air pollution. The major components of particulate matter in air pollution are sulfates, nitrates, ammonia, sodium chloride, black carbon, mineral dust and water. Many of these come from mining activity

2. Water pollution: The chemicals released from mining activities cause contamination of soil, groundwater, surface water. Mining activities cause noise pollution too.

3. Land subsidence: This can in turn cause damages to the buildings, surface drains, highways, water and sewage lines, etc existing on the ground

4. Land degradation: After mining is completed, the waste products of mining, known as mine-spoils, are simply left in their original location. This results in significant land degradation and pollution in those areas and nearby areas. Mining can cause erosion, sinkholes, loss of biodiversity, or the contamination of soil, groundwater, and surface water by chemicals emitted from mining processes. These processes also affect the atmosphere through carbon emissions which contributes to climate change

5. Deforestation: With open cast mining the overburden, which may be covered in forest, must be removed before the mining can commence. Although the deforestation due to mining may be small compared to the total amount it may lead to species extinction if there is a high level of local endemism

6. Noise, ground vibrations and dust pollution. Blasting causes heavy ground vibrations, damages to nearby structures, buildings, etc, besides causing irritation to the residents

7. Mining accidents and health hazards: The dust produced during mining operations is highly injurious to health and causes diseases related to lungs. Other common diseases are due to high levels of toxicity and tuberculosis, cough and cold, malaria, diarrohea, skin diseases, staining of teeth, joint pains, etc