Geographical Perspective on Selected Issues and Problems Class 12 Notes Geography Chapter 12 - CBSE

Chapter : 12

What Are Geographical Perspective On Selected Issues And Problems ?

Environmental Pollution

Environmental pollution results from ‘the release of substances and energy from waste products of human activities. There are many types of pollution. They are classified on the basis of medium through which pollutants are transported and diffused. Pollution can be classified into:

Air Pollution

  • Air pollution is taken as addition of contaminants, like dust, fumes, gas, fog, odour, smoke or vapour to the air in substantial proportion and duration that may be harmful to flora and fauna and to property.
  • Combustion of fossil fuels, mining and industries are the main sources of air pollution.
  • These processes release oxides of sulphur and nitrogen, hydrocarbons, carbon dioxide, carbon monoxide, lead and asbestos.
  • Air pollution causes various diseases related to respiratory, nervous and circulatory systems.

Water Pollution

  •  It contains small quantities of suspended particles, organic and inorganic substances.
  • When concentration of these substances increases, the water becomes polluted, and hence becomes unfit  for use. In such a situation, the self-purifying capacity of water is unable to purify the water. Though water pollutants are also created from natural sources (erosion, landslides, decay and decomposition of plants and
    animals, etc.) pollutants from human activities are the real causes of concern.
  •  Human beings pollute the water through industrial, agricultural and cultural activities. Among these activities, industry is the most significant contributor.
  • Major water polluting industries are leather, pulp and paper, textiles and chemicals.
  • Various types of chemicals used in modern agriculture such as inorganic fertilizers, pesticides and herbicides are also pollution generating components. These chemicals are washed down to rivers, lakes and tanks. These chemicals also infiltrate the soil to reach the ground water.
  • Cultural activities such as pilgrimage, religious fairs, tourism, etc. also cause water pollution.
  • Water pollution is a source of various water- borne diseases. The diseases commonly caused due to contaminated water are diarrhoea, intestinal worms, hepatitis, etc.
  • The World Health Organization shows that about one-fourth of the communicable diseases in India are water-borne.

Land Pollution

Soil contamination, soil pollution, or land pollution as a part of land degradation is caused by the presence of xenobiotic chemicals or other alteration in the natural soil environment. It is typically caused by industrial activity, agricultural chemicals or improper disposal of waste. Soil is not a renewable resource. Its degradation can be rapid (a few years or decades) while it takes several thousands of years to form and regenerate.

Noise Pollution

  • Noise pollution refers to the state of unbearable and uncomfortable to human beings which is caused by noise from different sources. This matter has become a serious concern only in recent years due to a variety of technological innovations.
  • The main sources of noise pollution are various factories, mechanised construction and demolition works, automobiles and aircraft, etc.
  • Of all these sources, the biggest nuisance is the noise produced by traffic, because its intensity and nature depend upon factors, such as the type of aircraft, vehicle, train and the condition of road, as well as, that of vehicle (in case of automobiles).
  • The level of steady noise is measured by sound level expressed in terms of decibels (dB).

Urban Waste Disposal

  • Urban areas are generally marked by overcrowding, congestion, inadequate facilities to support the fast growing population and consequent poor sanitary conditions and foul air.
  • Solid waste refers to a variety of old and used articles, for example stained small pieces of metals, broken glassware, plastic containers, polythene bags, ash, floppies, CDs, etc., dumped at different places.
  • These discarded materials are also termed as refuse, garbage and rubbish, etc., and are disposed of from two sources : (i) household or domestic establishments, and (ii) industrial or commercial establishments.
  • The household wastes are disposed off either on public lands or on private contractors’ sites, whereas the solid wastes of industrial units are collected and disposed off through public (municipal) facilities at low lying public grounds (landfill areas).
  • The huge turn out of ashes and debris from industries, thermal power houses and building constructions or demolitions have posed problems of serious consequences.
  • Solid wastes cause health hazard through creation of obnoxious smell, and harbouring of flies and rodents, which act as carriers of diseases like typhoid, diphtheria, diarrhoea, malaria and cholera, etc.
  • Urban waste disposal is a serious problem in India.

Urbanization

  • Urbanization (or urbanisation) refers to the population shift from rural to urban areas, the corresponding decrease in the proportion of people living in rural areas, and the ways in which societies adapt to this change. It is predominantly the process by which towns and cities are formed and become larger as more people begin
    living and working in central areas.

Rural-urban Migration

  • Population flow from rural to urban areas is caused by many factors, like high demand in urban areas, low job opportunities in rural areas and unbalanced pattern of development between urban and rural areas.
  • In India, population in cities is rapidly increasing. Due to low opportunities in smaller and medium cities, the poor people generally bypass these small cities and directly come to the mega cities for their livelihood.

Land Degradation

  • The pressure on agricultural land increases not only due to the limited availability but also by deterioration of quality of agricultural land. Soil erosion, waterlogging, salinisation and alkalinisation of land lead to land degradation.
  • Land is degraded and productivity declines. Land degradation is generally understood either as a temporary or a permanent decline in productive capacity of the land.
  • Though all degraded land may not be wasteland, but unchecked process of degradation may lead to the conversion to wasteland.
  • There are two processes that induce land degradation. These are natural and createdby human beings. National Remote Sensing Centre (NRSC) has classified wastelands by using remote sensing techniques and it is possible to categorise these wastelands according to the processes that have created them.
  • There are other types of degraded lands such as waterlogged and marshy areas, land affected by salinity and alkalinity and land with or without scrub, which have largely been caused by natural as well as human factors.
  • There are some other types of wastelands such as degraded shifting cultivation area, degraded land under plantation crops, degraded forests, degraded pastures, mining and industrial wastelands, are caused by human actions.
  • The Swachh Bharat Mission (SBM) is part of the urban renewal mission launched by the Government of India to improve the quality of life in urban slums.